[RFC,v2] /net: memory interface (memif)

Message ID 20181210100639.30244-1-jgrajcia@cisco.com (mailing list archive)
State Superseded, archived
Headers
Series [RFC,v2] /net: memory interface (memif) |

Checks

Context Check Description
ci/checkpatch warning coding style issues
ci/Intel-compilation success Compilation OK

Commit Message

  Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
---
 config/common_base                          |    5 +
 config/common_linuxapp                      |    1 +
 drivers/net/Makefile                        |    1 +
 drivers/net/memif/Makefile                  |   29 +
 drivers/net/memif/memif.h                   |  156 +++
 drivers/net/memif/memif_socket.c            | 1085 +++++++++++++++++
 drivers/net/memif/memif_socket.h            |   57 +
 drivers/net/memif/meson.build               |    8 +
 drivers/net/memif/rte_eth_memif.c           | 1172 +++++++++++++++++++
 drivers/net/memif/rte_eth_memif.h           |  189 +++
 drivers/net/memif/rte_pmd_memif_version.map |    4 +
 drivers/net/meson.build                     |    1 +
 mk/rte.app.mk                               |    1 +
 13 files changed, 2709 insertions(+)
 create mode 100644 drivers/net/memif/Makefile
 create mode 100644 drivers/net/memif/memif.h
 create mode 100644 drivers/net/memif/memif_socket.c
 create mode 100644 drivers/net/memif/memif_socket.h
 create mode 100644 drivers/net/memif/meson.build
 create mode 100644 drivers/net/memif/rte_eth_memif.c
 create mode 100644 drivers/net/memif/rte_eth_memif.h
 create mode 100644 drivers/net/memif/rte_pmd_memif_version.map
  

Comments

Burakov, Anatoly Dec. 10, 2018, 10:42 a.m. UTC | #1
On 10-Dec-18 10:06 AM, Jakub Grajciar wrote:
> Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
> ---

As a general comment, some description/cover letter would have been nice.

> +
> +	memif_msg_disconnect_t *d = &e->msg.disconnect;
> +
> +	e->msg.type = MEMIF_MSG_TYPE_DISCONNECT;
> +	d->code = err_code;
> +
> +	if (reason != NULL) {
> +		strncpy((char *)d->string, reason, strlen(reason));
> +		if (cc->pmd != NULL) {
> +			strncpy(cc->pmd->local_disc_string, reason,
> +				strlen(reason));
> +		}

I haven't looked at the entire thing, this is just something that caught 
my eye during quick skimming through code.

On the face of it, this looks dangerous - you're setting the destination 
buffer size from source buffer size. What if `d->string` is shorter than 
`reason`?
  
Bruce Richardson Dec. 10, 2018, 10:50 a.m. UTC | #2
> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Burakov, Anatoly
> Sent: Monday, December 10, 2018 10:43 AM
> To: Jakub Grajciar <jgrajcia@cisco.com>; dev@dpdk.org
> Subject: Re: [dpdk-dev] [RFC v2] /net: memory interface (memif)
> 
> On 10-Dec-18 10:06 AM, Jakub Grajciar wrote:
> > Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
> > ---
> 
> As a general comment, some description/cover letter would have been nice.
> 
> > +
> > +	memif_msg_disconnect_t *d = &e->msg.disconnect;
> > +
> > +	e->msg.type = MEMIF_MSG_TYPE_DISCONNECT;
> > +	d->code = err_code;
> > +
> > +	if (reason != NULL) {
> > +		strncpy((char *)d->string, reason, strlen(reason));
> > +		if (cc->pmd != NULL) {
> > +			strncpy(cc->pmd->local_disc_string, reason,
> > +				strlen(reason));
> > +		}
> 
> I haven't looked at the entire thing, this is just something that caught
> my eye during quick skimming through code.
> 
> On the face of it, this looks dangerous - you're setting the destination
> buffer size from source buffer size. What if `d->string` is shorter than
> `reason`?
>

And strncpy is dangerous - use strlcpy instead.

/Bruce
  
Wiles, Keith Dec. 10, 2018, 2:48 p.m. UTC | #3
> On Dec 10, 2018, at 4:06 AM, Jakub Grajciar <jgrajcia@cisco.com> wrote:

I do not like being the coding style police, but that is most of the comments here and I will try to test this one later this week. Plus I am sure I missed some style problems, if you have not read the coding style for DPDK please have a read.

http://doc.dpdk.org/guides/contributing/coding_style.html

One comment, why did you include all of the code to handle memif instead of including the libmemif.a from VPP. I worry if libmemif is changed then we have a breakage. I do not mind the PMD being standalone and I do like not having the dependence.

As I did not dive into the code much it does look reasonable and I hope to give it a try later this week.
> 
> Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
> ---
> config/common_base                          |    5 +
> config/common_linuxapp                      |    1 +
> drivers/net/Makefile                        |    1 +
> drivers/net/memif/Makefile                  |   29 +
> drivers/net/memif/memif.h                   |  156 +++
> drivers/net/memif/memif_socket.c            | 1085 +++++++++++++++++
> drivers/net/memif/memif_socket.h            |   57 +
> drivers/net/memif/meson.build               |    8 +
> drivers/net/memif/rte_eth_memif.c           | 1172 +++++++++++++++++++
> drivers/net/memif/rte_eth_memif.h           |  189 +++
> drivers/net/memif/rte_pmd_memif_version.map |    4 +
> drivers/net/meson.build                     |    1 +
> mk/rte.app.mk                               |    1 +
> 13 files changed, 2709 insertions(+)
> create mode 100644 drivers/net/memif/Makefile
> create mode 100644 drivers/net/memif/memif.h
> create mode 100644 drivers/net/memif/memif_socket.c
> create mode 100644 drivers/net/memif/memif_socket.h
> create mode 100644 drivers/net/memif/meson.build
> create mode 100644 drivers/net/memif/rte_eth_memif.c
> create mode 100644 drivers/net/memif/rte_eth_memif.h
> create mode 100644 drivers/net/memif/rte_pmd_memif_version.map
> 
> diff --git a/config/common_base b/config/common_base
> index d12ae98bc..b8ed10ae5 100644
> --- a/config/common_base
> +++ b/config/common_base
> @@ -403,6 +403,11 @@ CONFIG_RTE_LIBRTE_VMXNET3_DEBUG_TX_FREE=n
> #
> CONFIG_RTE_LIBRTE_PMD_AF_PACKET=n
> 
> +#
> +# Compile Memory Interface PMD driver (Linux only)
> +#
> +CONFIG_RTE_LIBRTE_PMD_MEMIF=n
> +
> #
> # Compile link bonding PMD library
> #
> diff --git a/config/common_linuxapp b/config/common_linuxapp
> index 6c1c8d0f4..42cbde8f5 100644
> --- a/config/common_linuxapp
> +++ b/config/common_linuxapp
> @@ -18,6 +18,7 @@ CONFIG_RTE_LIBRTE_VHOST_POSTCOPY=n
> CONFIG_RTE_LIBRTE_PMD_VHOST=y
> CONFIG_RTE_LIBRTE_IFC_PMD=y
> CONFIG_RTE_LIBRTE_PMD_AF_PACKET=y
> +CONFIG_RTE_LIBRTE_PMD_MEMIF=y
> CONFIG_RTE_LIBRTE_PMD_SOFTNIC=y
> CONFIG_RTE_LIBRTE_PMD_TAP=y
> CONFIG_RTE_LIBRTE_AVP_PMD=y
> diff --git a/drivers/net/Makefile b/drivers/net/Makefile
> index c0386feb9..0feab5241 100644
> --- a/drivers/net/Makefile
> +++ b/drivers/net/Makefile
> @@ -32,6 +32,7 @@ DIRS-$(CONFIG_RTE_LIBRTE_FM10K_PMD) += fm10k
> DIRS-$(CONFIG_RTE_LIBRTE_I40E_PMD) += i40e
> DIRS-$(CONFIG_RTE_LIBRTE_IXGBE_PMD) += ixgbe
> DIRS-$(CONFIG_RTE_LIBRTE_LIO_PMD) += liquidio
> +DIRS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += memif
> DIRS-$(CONFIG_RTE_LIBRTE_MLX4_PMD) += mlx4
> DIRS-$(CONFIG_RTE_LIBRTE_MLX5_PMD) += mlx5
> DIRS-$(CONFIG_RTE_LIBRTE_MVNETA_PMD) += mvneta
> diff --git a/drivers/net/memif/Makefile b/drivers/net/memif/Makefile
> new file mode 100644
> index 000000000..a82448423
> --- /dev/null
> +++ b/drivers/net/memif/Makefile
> @@ -0,0 +1,29 @@
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> +
> +include $(RTE_SDK)/mk/rte.vars.mk
> +
> +#
> +# library name
> +#
> +LIB = librte_pmd_memif.a
> +
> +EXPORT_MAP := rte_pmd_memif_version.map
> +
> +LIBABIVER := 1
> +
> +CFLAGS += -O3
> +CFLAGS += -I$(SRCDIR)
> +CFLAGS += $(WERROR_FLAGS)
> +CFLAGS += -Wno-pointer-arith
> +LDLIBS += -lrte_eal -lrte_mbuf -lrte_mempool -lrte_ring
> +LDLIBS += -lrte_ethdev -lrte_net -lrte_kvargs
> +LDLIBS += -lrte_bus_vdev
> +
> +#
> +# all source are stored in SRCS-y
> +#
> +SRCS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += rte_eth_memif.c
> +SRCS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += memif_socket.c
> +
> +include $(RTE_SDK)/mk/rte.lib.mk
> diff --git a/drivers/net/memif/memif.h b/drivers/net/memif/memif.h
> new file mode 100644
> index 000000000..6a23dbad7
> --- /dev/null
> +++ b/drivers/net/memif/memif.h
> @@ -0,0 +1,156 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#ifndef _MEMIF_H_
> +#define _MEMIF_H_
> +
> +#ifndef MEMIF_CACHELINE_SIZE
> +#define MEMIF_CACHELINE_SIZE 64
> +#endif
> +
> +#define MEMIF_COOKIE		0x3E31F20
> +#define MEMIF_VERSION_MAJOR	2
> +#define MEMIF_VERSION_MINOR	0
> +#define MEMIF_VERSION		((MEMIF_VERSION_MAJOR << 8) | MEMIF_VERSION_MINOR)
> +
> +/*
> + *  Type definitions
> + */
> +
> +typedef enum memif_msg_type {
> +	MEMIF_MSG_TYPE_NONE = 0,
> +	MEMIF_MSG_TYPE_ACK = 1,
> +	MEMIF_MSG_TYPE_HELLO = 2,
> +	MEMIF_MSG_TYPE_INIT = 3,
> +	MEMIF_MSG_TYPE_ADD_REGION = 4,
> +	MEMIF_MSG_TYPE_ADD_RING = 5,
> +	MEMIF_MSG_TYPE_CONNECT = 6,
> +	MEMIF_MSG_TYPE_CONNECTED = 7,
> +	MEMIF_MSG_TYPE_DISCONNECT = 8,
> +} memif_msg_type_t;
> +
> +typedef enum {
> +	MEMIF_RING_S2M = 0,
> +	MEMIF_RING_M2S = 1
> +} memif_ring_type_t;
> +
> +typedef enum {
> +	MEMIF_INTERFACE_MODE_ETHERNET = 0,
> +	MEMIF_INTERFACE_MODE_IP = 1,
> +	MEMIF_INTERFACE_MODE_PUNT_INJECT = 2,
> +} memif_interface_mode_t;
> +
> +typedef uint16_t memif_region_index_t;
> +typedef uint32_t memif_region_offset_t;
> +typedef uint64_t memif_region_size_t;
> +typedef uint16_t memif_ring_index_t;
> +typedef uint32_t memif_interface_id_t;
> +typedef uint16_t memif_version_t;
> +typedef uint8_t memif_log2_ring_size_t;
> +
> +/*
> + *  Socket messages
> + */
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint8_t name[32];
> +	memif_version_t min_version;
> +	memif_version_t max_version;
> +	memif_region_index_t max_region;
> +	memif_ring_index_t max_m2s_ring;
> +	memif_ring_index_t max_s2m_ring;
> +	memif_log2_ring_size_t max_log2_ring_size;
> +} memif_msg_hello_t;

Normally we have comments after the members of a structure for documentation, not sure how everyone else wants it done.

	char foo;	/**< The description of foo */
> +
> +typedef struct __attribute__ ((packed)) {
> +	memif_version_t version;
> +	memif_interface_id_t id;
> +	memif_interface_mode_t mode:8;
> +	uint8_t secret[24];
> +	uint8_t name[32];
> +} memif_msg_init_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	memif_region_index_t index;
> +	memif_region_size_t size;
> +} memif_msg_add_region_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint16_t flags;
> +#define MEMIF_MSG_ADD_RING_FLAG_S2M	(1 << 0)
> +	memif_ring_index_t index;
> +	memif_region_index_t region;
> +	memif_region_offset_t offset;
> +	memif_log2_ring_size_t log2_ring_size;
> +	uint16_t private_hdr_size;	/* used for private metadata */
> +} memif_msg_add_ring_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint8_t if_name[32];
> +} memif_msg_connect_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint8_t if_name[32];
> +} memif_msg_connected_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint32_t code;
> +	uint8_t string[96];
> +} memif_msg_disconnect_t;
> +
> +typedef struct __attribute__ ((packed, aligned(128))) {
> +	memif_msg_type_t type:16;

WE normally use RTE_C11_STD before unions without names a variable name and using the internal names directly.
> +	union {
> +		memif_msg_hello_t hello;
> +		memif_msg_init_t init;
> +		memif_msg_add_region_t add_region;
> +		memif_msg_add_ring_t add_ring;
> +		memif_msg_connect_t connect;
> +		memif_msg_connected_t connected;
> +		memif_msg_disconnect_t disconnect;
> +	};
> +} memif_msg_t;
> +
> +_Static_assert(sizeof(memif_msg_t) == 128, "Size of memif_msg_t must be 128");
> +
> +/*
> + *  Ring and Descriptor Layout
> + */
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint16_t flags;
> +#define MEMIF_DESC_FLAG_NEXT (1 << 0)
> +	memif_region_index_t region;
> +	uint32_t length;
> +	memif_region_offset_t offset;
> +	uint32_t metadata;
> +} memif_desc_t;
> +
> +_Static_assert(sizeof(memif_desc_t) == 16,
> +	       "Size of memif_dsct_t must be 16 bytes");
> +
> +#define MEMIF_CACHELINE_ALIGN_MARK(mark) \
> +  uint8_t mark[0] __attribute__((aligned(MEMIF_CACHELINE_SIZE)))
> +
> +typedef struct {
> +	MEMIF_CACHELINE_ALIGN_MARK(cacheline0);
> +	uint32_t cookie;
> +	uint16_t flags;
> +#define MEMIF_RING_FLAG_MASK_INT 1
> +	volatile uint16_t head;
> +	 MEMIF_CACHELINE_ALIGN_MARK(cacheline1);
> +	volatile uint16_t tail;
> +	 MEMIF_CACHELINE_ALIGN_MARK(cacheline2);
> +	memif_desc_t desc[0];
> +} memif_ring_t;

> +
> +#endif				/* _MEMIF_H_ */
> +
> +/*
> + * fd.io coding-style-patch-verification: ON
> + *
> + * Local Variables:
> + * eval: (c-set-style "gnu")
> + * End:
> + */
> diff --git a/drivers/net/memif/memif_socket.c b/drivers/net/memif/memif_socket.c
> new file mode 100644
> index 000000000..afd4ac888
> --- /dev/null
> +++ b/drivers/net/memif/memif_socket.c
> @@ -0,0 +1,1085 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#include <stdlib.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <sys/types.h>
> +#include <sys/socket.h>
> +#include <sys/un.h>
> +#include <sys/ioctl.h>
> +#include <errno.h>
> +
> +#include <rte_version.h>
> +#include <rte_mbuf.h>
> +#include <rte_ether.h>
> +#include <rte_ethdev_driver.h>
> +#include <rte_ethdev_vdev.h>
> +#include <rte_malloc.h>
> +#include <rte_kvargs.h>
> +#include <rte_bus_vdev.h>
> +#include <rte_hash.h>
> +#include <rte_jhash.h>
> +
> +#include <rte_eth_memif.h>
> +#include <memif_socket.h>
> +
> +static void memif_intr_handler(void *arg);
> +
> +static inline ssize_t memif_msg_send(int fd, memif_msg_t * msg, int afd)

The coding guide states the function type is on a line by itself section 1.7.2
http://doc.dpdk.org/guides/contributing/coding_style.html

> +{
> +	struct msghdr mh = { 0 };
> +	struct iovec iov[1];
> +	char ctl[CMSG_SPACE(sizeof(int))];
> +
> +	iov[0].iov_base = (void *)msg;
> +	iov[0].iov_len = sizeof(memif_msg_t);
> +	mh.msg_iov = iov;
> +	mh.msg_iovlen = 1;
> +
> +	if (afd > 0) {
> +		struct cmsghdr *cmsg;
> +		memset(&ctl, 0, sizeof(ctl));
> +		mh.msg_control = ctl;
> +		mh.msg_controllen = sizeof(ctl);
> +		cmsg = CMSG_FIRSTHDR(&mh);
> +		cmsg->cmsg_len = CMSG_LEN(sizeof(int));
> +		cmsg->cmsg_level = SOL_SOCKET;
> +		cmsg->cmsg_type = SCM_RIGHTS;
> +		rte_memcpy(CMSG_DATA(cmsg), &afd, sizeof(int));
> +	}
> +
> +	return sendmsg(fd, &mh, 0);
> +}
> +
> +static inline int memif_msg_send_from_queue(struct memif_control_channel *cc)
> +{
> +	ssize_t size;
> +	int ret = 0;
> +	struct memif_msg_queue_elt *e;

Space after function declares and the first line of the function, this also includes declares inside a block of code {}
> +	e = TAILQ_FIRST(&cc->msg_queue);
> +	if (e == NULL)
> +		return 0;
> +
> +	size = memif_msg_send(cc->intr_handle.fd, &e->msg, e->fd);
> +	if (size != sizeof(memif_msg_t)) {
> +		MIF_LOG(ERR, "sendmsg fail: %s.", strerror(errno));
> +		ret = -1;
> +	} else {
> +		MIF_LOG(DEBUG, "%s: Sent msg type %u.",
> +			(cc->pmd !=
> +			 NULL) ? rte_vdev_device_name(cc->pmd->
> +						      vdev) : "memif_driver",
> +			e->msg.type);
> +	}
> +	TAILQ_REMOVE(&cc->msg_queue, e, next);
> +	rte_free(e);
> +
> +	return ret;
> +}
> +
> +static inline struct memif_msg_queue_elt *memif_msg_enq(struct
> +							memif_control_channel
> +							*cc)
> +{
> +	struct memif_msg_queue_elt *e = rte_zmalloc("memif_msg",
> +						    sizeof(struct
> +							   memif_msg_queue_elt),
> +						    0);

> +	if (e == NULL) {
> +		MIF_LOG(ERR, "Failed to allocate control message.");
> +		return NULL;
> +	}
> +
> +	e->fd = -1;
> +	TAILQ_INSERT_TAIL(&cc->msg_queue, e, next);
> +
> +	return e;
> +}
> +
> +void
> +memif_msg_enq_disconnect(struct memif_control_channel *cc, const char *reason,
> +			 int err_code)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(cc);


> +	if (e == NULL) {
> +		MIF_LOG(WARNING, "%s: Failed to enqueue disconnect message.",
> +			(cc->pmd !=
> +			 NULL) ? rte_vdev_device_name(cc->pmd->
> +						      vdev) : "memif_driver");
> +		return;
> +	}
> +
> +	memif_msg_disconnect_t *d = &e->msg.disconnect;
> +
> +	e->msg.type = MEMIF_MSG_TYPE_DISCONNECT;
> +	d->code = err_code;
> +
> +	if (reason != NULL) {
> +		strncpy((char *)d->string, reason, strlen(reason));
> +		if (cc->pmd != NULL) {
> +			strncpy(cc->pmd->local_disc_string, reason,
> +				strlen(reason));
> +		}
> +	}
> +}
> +
> +static int memif_msg_enq_hello(struct memif_control_channel *cc)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(cc);


> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_hello_t *h = &e->msg.hello;
> +
> +	e->msg.type = MEMIF_MSG_TYPE_HELLO;
> +	h->min_version = MEMIF_VERSION;
> +	h->max_version = MEMIF_VERSION;
> +	h->max_s2m_ring = ETH_MEMIF_MAX_NUM_Q_PAIRS;
> +	h->max_m2s_ring = ETH_MEMIF_MAX_NUM_Q_PAIRS;
> +	h->max_region = ETH_MEMIF_MAX_REGION_IDX;
> +	h->max_log2_ring_size = ETH_MEMIF_MAX_LOG2_RING_SIZE;
> +
> +	strncpy((char *)h->name, rte_version(), strlen(rte_version()));
> +
> +	return 0;
> +}
> +
> +static int memif_msg_receive_hello(struct pmd_internals *pmd, memif_msg_t * msg)
> +{
> +	memif_msg_hello_t *h = &msg->hello;
> +
> +	if (h->min_version > MEMIF_VERSION || h->max_version < MEMIF_VERSION) {
> +		memif_msg_enq_disconnect(pmd->cc, "Incompatible memif version",
> +					 0);
> +		return -1;
> +	}
> +
> +	/* Set parameters for active connection */
> +	pmd->run.num_s2m_rings = memif_min(h->max_s2m_ring + 1,
> +					   pmd->cfg.num_s2m_rings);
> +	pmd->run.num_m2s_rings = memif_min(h->max_m2s_ring + 1,
> +					   pmd->cfg.num_m2s_rings);
> +	pmd->run.log2_ring_size = memif_min(h->max_log2_ring_size,
> +					    pmd->cfg.log2_ring_size);
> +	pmd->run.buffer_size = pmd->cfg.buffer_size;
> +
> +	strncpy(pmd->remote_name, (char *)h->name, strlen((char *)h->name));
> +
> +	MIF_LOG(DEBUG, "%s: Connecting to %s.",
> +		rte_vdev_device_name(pmd->vdev), pmd->remote_name);
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_init(struct memif_control_channel *cc, memif_msg_t * msg)
> +{
> +	memif_msg_init_t *i = &msg->init;
> +	struct memif_socket_pmd_list_elt *elt;
> +	struct pmd_internals *pmd;
> +
> +	if (i->version != MEMIF_VERSION) {
> +		memif_msg_enq_disconnect(cc, "Incompatible memif version", 0);
> +		return -1;
> +	}
> +
> +	if (cc->socket == NULL) {
> +		memif_msg_enq_disconnect(cc, "Device error", 0);
> +		return -1;
> +	}
> +
> +	/* Find device with requested ID */
> +	TAILQ_FOREACH(elt, &cc->socket->pmd_queue, next) {
> +		pmd = elt->pmd;
> +		if (((pmd->flags & ETH_MEMIF_FLAG_DISABLED) == 0)
> +		    && (pmd->id == i->id)) {
> +			/* assign control channel to device */
> +			cc->pmd = pmd;
> +			pmd->cc = cc;
> +
> +			if (i->mode != MEMIF_INTERFACE_MODE_ETHERNET) {
> +				memif_msg_enq_disconnect(pmd->cc,
> +							 "Only ethernet mode supported",
> +							 0);
> +				return -1;
> +			}
> +
> +			if (pmd->flags && (ETH_MEMIF_FLAG_CONNECTING |
> +					   ETH_MEMIF_FLAG_CONNECTED)) {
> +				memif_msg_enq_disconnect(pmd->cc,
> +							 "Already connected",
> +							 0);
> +				return -1;
> +			}
> +			strncpy(pmd->remote_name, (char *)i->name,
> +				strlen((char *)i->name));
> +
> +			if (*pmd->secret != '\0') {
> +				if (*i->secret == '\0') {
> +					memif_msg_enq_disconnect(pmd->cc,
> +								 "Secret required",
> +								 0);
> +					return -1;
> +				}
> +				if (strcmp(pmd->secret, (char *)i->secret) != 0) {
> +					memif_msg_enq_disconnect(pmd->cc,
> +								 "Incorrect secret",
> +								 0);
> +					return -1;
> +				}
> +			}
> +
> +			pmd->flags |= ETH_MEMIF_FLAG_CONNECTING;
> +			return 0;
> +		}
> +	}
> +
> +	/* ID not found on this socket */
> +	MIF_LOG(DEBUG, "ID %u not found.", i->id);
> +	memif_msg_enq_disconnect(cc, "ID not found", 0);
> +	return -1;
> +}
> +
> +static int
> +memif_msg_receive_add_region(struct pmd_internals *pmd, memif_msg_t * msg,
> +			     int fd)
> +{
> +	memif_msg_add_region_t *ar = &msg->add_region;
> +
> +	if (fd < 0) {
> +		memif_msg_enq_disconnect(pmd->cc, "Missing region fd", 0);
> +		return -1;
> +	}
> +
> +	struct memif_region *mr;
> +
> +	if (ar->index > ETH_MEMIF_MAX_REGION_IDX) {
> +		memif_msg_enq_disconnect(pmd->cc, "Invalid region index", 0);
> +		return -1;
> +	}
> +
> +	mr = rte_realloc(pmd->regions, sizeof(struct memif_region) *
> +			 (ar->index + 1), 0);
> +	if (mr == NULL) {
> +		memif_msg_enq_disconnect(pmd->cc, "Device error", 0);
> +		return -1;
> +	}
> +
> +	pmd->regions = mr;
> +	pmd->regions[ar->index].fd = fd;
> +	pmd->regions[ar->index].region_size = ar->size;
> +	pmd->regions[ar->index].addr = NULL;
> +	pmd->regions_num++;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_add_ring(struct pmd_internals *pmd, memif_msg_t * msg, int fd)
> +{
> +	memif_msg_add_ring_t *ar = &msg->add_ring;
> +
> +	if (fd < 0) {
> +		memif_msg_enq_disconnect(pmd->cc, "Missing interrupt fd", 0);
> +		return -1;
> +	}
> +
> +	struct memif_queue *mq;
> +
> +	/* check if we have enough queues */
> +	if (ar->flags & MEMIF_MSG_ADD_RING_FLAG_S2M) {
> +		if (ar->index >= pmd->cfg.num_s2m_rings) {
> +			memif_msg_enq_disconnect(pmd->cc, "Invalid ring index",
> +						 0);
> +			return -1;
> +		}
> +		pmd->run.num_s2m_rings++;
> +	} else {
> +		if (ar->index >= pmd->cfg.num_m2s_rings) {
> +			memif_msg_enq_disconnect(pmd->cc, "Invalid ring index",
> +						 0);
> +			return -1;
> +		}
> +		pmd->run.num_m2s_rings++;
> +	}
> +
> +	mq = (ar->flags & MEMIF_MSG_ADD_RING_FLAG_S2M) ?
> +	    &pmd->rx_queues[ar->index] : &pmd->tx_queues[ar->index];
> +
> +	mq->intr_handle.fd = fd;
> +	mq->log2_ring_size = ar->log2_ring_size;
> +	mq->region = ar->region;
> +	mq->offset = ar->offset;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_connect(struct pmd_internals *pmd, memif_msg_t * msg)
> +{
> +	memif_msg_connect_t *c = &msg->connect;
> +	int ret;
> +
> +	ret = memif_connect(pmd);
> +	if (ret < 0)
> +		return ret;
> +
> +	strncpy(pmd->remote_if_name, (char *)c->if_name,
> +		strlen((char *)c->if_name));
> +	MIF_LOG(INFO, "%s: Remote interface %s connected.",
> +		rte_vdev_device_name(pmd->vdev), pmd->remote_if_name);
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_connected(struct pmd_internals *pmd, memif_msg_t * msg)
> +{
> +	memif_msg_connected_t *c = &msg->connected;
> +	int ret;
> +
> +	ret = memif_connect(pmd);
> +	if (ret < 0)
> +		return ret;
> +
> +	strncpy(pmd->remote_if_name, (char *)c->if_name,
> +		strlen((char *)c->if_name));
> +	MIF_LOG(INFO, "%s: Remote interface %s connected.",
> +		rte_vdev_device_name(pmd->vdev), pmd->remote_if_name);
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_disconnect(struct pmd_internals *pmd, memif_msg_t * msg)
> +{
> +	memif_msg_disconnect_t *d = &msg->disconnect;
> +
> +	memset(pmd->remote_disc_string, 0, sizeof(pmd->remote_disc_string));
> +	strncpy(pmd->remote_disc_string, (char *)d->string,
> +		strlen((char *)d->string));
> +
> +	MIF_LOG(INFO, "%s: Disconnect received: %s",
> +		rte_vdev_device_name(pmd->vdev), pmd->remote_disc_string);
> +
> +	memset(pmd->local_disc_string, 0, 96);
> +	memif_disconnect(rte_eth_dev_allocated
> +			 (rte_vdev_device_name(pmd->vdev)));
> +	return 0;
> +}
> +
> +static int memif_msg_enq_ack(struct pmd_internals *pmd)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
> +	if (e == NULL)
> +		return -1;
> +
> +	e->msg.type = MEMIF_MSG_TYPE_ACK;
> +
> +	return 0;
> +}
> +
> +static int memif_msg_enq_init(struct pmd_internals *pmd)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_init_t *i = &e->msg.init;
> +
> +	e->msg.type = MEMIF_MSG_TYPE_INIT;
> +	i->version = MEMIF_VERSION;
> +	i->id = pmd->id;
> +	i->mode = MEMIF_INTERFACE_MODE_ETHERNET;
> +
> +	strncpy((char *)i->name, rte_version(), strlen(rte_version()));
> +
> +	if (pmd->secret) {
> +		strncpy((char *)i->secret, pmd->secret, sizeof(i->secret) - 1);
> +	}

DPDK does not put {} around a single line blocks of code for if, while, for, ...

> +
> +	return 0;
> +}
> +
> +static int memif_msg_enq_add_region(struct pmd_internals *pmd, uint8_t idx)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);

> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_add_region_t *ar = &e->msg.add_region;
> +	struct memif_region *mr = &pmd->regions[idx];
> +
> +	e->msg.type = MEMIF_MSG_TYPE_ADD_REGION;
> +	e->fd = mr->fd;
> +	ar->index = idx;
> +	ar->size = mr->region_size;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_enq_add_ring(struct pmd_internals *pmd, uint8_t idx,
> +		       memif_ring_type_t type)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);

> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_add_ring_t *ar = &e->msg.add_ring;
> +	struct memif_queue *mq;
> +
> +	mq = (type == MEMIF_RING_S2M) ? &pmd->tx_queues[idx] :
> +	    &pmd->rx_queues[idx];
> +
> +	e->msg.type = MEMIF_MSG_TYPE_ADD_RING;
> +	e->fd = mq->intr_handle.fd;
> +	ar->index = idx;
> +	ar->offset = mq->offset;
> +	ar->region = mq->region;
> +	ar->log2_ring_size = mq->log2_ring_size;
> +	ar->flags = (type == MEMIF_RING_S2M) ? MEMIF_MSG_ADD_RING_FLAG_S2M : 0;
> +	ar->private_hdr_size = 0;
> +
> +	return 0;
> +}
> +
> +static int memif_msg_enq_connect(struct pmd_internals *pmd)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);

> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_connect_t *c = &e->msg.connect;
> +	const char *name = rte_vdev_device_name(pmd->vdev);
> +
> +	e->msg.type = MEMIF_MSG_TYPE_CONNECT;
> +	strncpy((char *)c->if_name, name, strlen(name));
> +
> +	return 0;
> +}
> +
> +static int memif_msg_enq_connected(struct pmd_internals *pmd)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);

> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_connected_t *c = &e->msg.connected;
> +
> +	const char *name = rte_vdev_device_name(pmd->vdev);
> +
> +	e->msg.type = MEMIF_MSG_TYPE_CONNECTED;
> +	strncpy((char *)c->if_name, name, strlen(name));
> +
> +	return 0;
> +}
> +
> +static void
> +memif_intr_unregister_handler(struct rte_intr_handle *intr_handle, void *arg)
> +{
> +	struct memif_msg_queue_elt *elt;
> +	struct memif_control_channel *cc = arg;

> +	/* close control channel fd */
> +	close(intr_handle->fd);
> +	/* clear message queue */
> +	while ((elt = TAILQ_FIRST(&cc->msg_queue)) != NULL) {
> +		TAILQ_REMOVE(&cc->msg_queue, elt, next);
> +		free(elt);
> +	}
> +	/* free control channel */
> +	rte_free(cc);
> +}
> +
> +void memif_disconnect(struct rte_eth_dev *dev)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_msg_queue_elt *elt;
> +	int i;
> +	int ret;
> +
> +	if (pmd->cc != NULL) {
> +		/* Clear control message queue (except disconnect message if any). */
> +		while ((elt = TAILQ_FIRST(&pmd->cc->msg_queue)) != NULL) {
> +			if (elt->msg.type != MEMIF_MSG_TYPE_DISCONNECT) {
> +				TAILQ_REMOVE(&pmd->cc->msg_queue, elt, next);
> +				free(elt);
> +			}
> +		}
> +		/* send disconnect message (if there is any in queue) */
> +		memif_msg_send_from_queue(pmd->cc);
> +
> +		/* at this point, there should be no more messages in queue */
> +		if (TAILQ_FIRST(&pmd->cc->msg_queue) != NULL) {
> +			MIF_LOG(WARNING,
> +				"%s: Unexpected message(s) in message queue.",
> +				rte_vdev_device_name(pmd->vdev));
> +		}

Single line block of code, the MIF_LOG() should have do { stmt; } while(0); around the macro.
> +
> +		if (pmd->cc->intr_handle.fd > 0) {
> +			ret =
> +			    rte_intr_callback_unregister(&pmd->cc->intr_handle,
> +							 memif_intr_handler,
> +							 pmd->cc);
> +			/*
> +			 * If callback is active (disconnecting based on
> +			 * received control message).
> +			 */
> +			if (ret == -EAGAIN) {
> +				ret =
> +				    rte_intr_callback_unregister_pending(&pmd->
> +									 cc->
> +									 intr_handle,
> +									 memif_intr_handler,
> +									 pmd->
> +									 cc,
> +									 memif_intr_unregister_handler);
> +			} else if (ret > 0) {
> +				close(pmd->cc->intr_handle.fd);
> +				rte_free(pmd->cc);
> +			}
> +			if (ret <= 0)
> +				MIF_LOG(WARNING,
> +					"%s: Failed to unregister control channel callback.",
> +					rte_vdev_device_name(pmd->vdev));
> +		}
> +	}
> +
> +	/* unconfig interrupts */
> +	struct memif_queue *mq;
> +	for (i = 0; i < pmd->cfg.num_s2m_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +		    &pmd->tx_queues[i] : &pmd->rx_queues[i];
> +		if (mq->intr_handle.fd > 0) {
> +			rte_intr_disable(&mq->intr_handle);
> +			close(mq->intr_handle.fd);
> +			mq->intr_handle.fd = -1;
> +		}
> +		mq->ring = NULL;
> +	}
> +	for (i = 0; i < pmd->cfg.num_m2s_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +		    &pmd->rx_queues[i] : &pmd->tx_queues[i];
> +		if (mq->intr_handle.fd > 0) {
> +			rte_intr_disable(&mq->intr_handle);
> +			close(mq->intr_handle.fd);
> +			mq->intr_handle.fd = -1;
> +		}
> +		mq->ring = NULL;
> +	}
> +
> +	memif_free_regions(pmd);
> +
> +	dev->data->dev_link.link_status = ETH_LINK_DOWN;
> +	pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTING;
> +	pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTED;
> +	MIF_LOG(DEBUG, "%s: Disconnected.", rte_vdev_device_name(pmd->vdev));
> +}
> +
> +static int memif_msg_receive(struct memif_control_channel *cc)
> +{
> +	char ctl[CMSG_SPACE(sizeof(int)) +
> +		 CMSG_SPACE(sizeof(struct ucred))] = { 0 };
> +	struct msghdr mh = { 0 };
> +	struct iovec iov[1];
> +	memif_msg_t msg = { 0 };
> +	ssize_t size;
> +	int ret = 0;
> +	struct ucred *cr __rte_unused;
> +	cr = 0;
> +	struct cmsghdr *cmsg;
> +	int afd = -1;
> +	int i;
> +
> +	iov[0].iov_base = (void *)&msg;
> +	iov[0].iov_len = sizeof(memif_msg_t);
> +	mh.msg_iov = iov;
> +	mh.msg_iovlen = 1;
> +	mh.msg_control = ctl;
> +	mh.msg_controllen = sizeof(ctl);
> +
> +	size = recvmsg(cc->intr_handle.fd, &mh, 0);
> +	if (size != sizeof(memif_msg_t)) {
> +		MIF_LOG(DEBUG, "Invalid message size.");
> +		memif_msg_enq_disconnect(cc, "Invalid message size", 0);
> +		return -1;
> +	}
> +	MIF_LOG(DEBUG, "Received msg type: %u.", msg.type);
> +
> +	cmsg = CMSG_FIRSTHDR(&mh);
> +	while (cmsg) {
> +		if (cmsg->cmsg_level == SOL_SOCKET) {
> +			if (cmsg->cmsg_type == SCM_CREDENTIALS) {
> +				cr = (struct ucred *)CMSG_DATA(cmsg);
> +			} else if (cmsg->cmsg_type == SCM_RIGHTS) {
> +				afd = *(int *)CMSG_DATA(cmsg);
> +			}
> +		}
> +		cmsg = CMSG_NXTHDR(&mh, cmsg);
> +	}
> +
> +	if ((cc->pmd == NULL) && msg.type != MEMIF_MSG_TYPE_INIT) {
> +		MIF_LOG(DEBUG, "Unexpected message.");
> +		memif_msg_enq_disconnect(cc, "Unexpected message", 0);
> +		return -1;
> +	}
> +
> +	/* get device from hash data */
> +	switch (msg.type) {
> +	case MEMIF_MSG_TYPE_ACK:
> +		break;
> +	case MEMIF_MSG_TYPE_HELLO:
> +		ret = memif_msg_receive_hello(cc->pmd, &msg);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_init_regions_and_queues(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_init(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		for (i = 0; i < cc->pmd->regions_num; i++) {
> +			ret = memif_msg_enq_add_region(cc->pmd, i);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		for (i = 0; i < cc->pmd->run.num_s2m_rings; i++) {
> +			ret = memif_msg_enq_add_ring(cc->pmd, i,
> +						     MEMIF_RING_S2M);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		for (i = 0; i < cc->pmd->run.num_m2s_rings; i++) {
> +			ret = memif_msg_enq_add_ring(cc->pmd, i,
> +						     MEMIF_RING_M2S);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		ret = memif_msg_enq_connect(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_INIT:
> +		ret = memif_msg_receive_init(cc, &msg);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_ack(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_ADD_REGION:
> +		ret = memif_msg_receive_add_region(cc->pmd, &msg, afd);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_ack(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_ADD_RING:
> +		ret = memif_msg_receive_add_ring(cc->pmd, &msg, afd);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_ack(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_CONNECT:
> +		ret = memif_msg_receive_connect(cc->pmd, &msg);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_connected(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_CONNECTED:
> +		ret = memif_msg_receive_connected(cc->pmd, &msg);
> +		break;
> +	case MEMIF_MSG_TYPE_DISCONNECT:
> +		ret = memif_msg_receive_disconnect(cc->pmd, &msg);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	default:
> +		memif_msg_enq_disconnect(cc, "Unknown message type", 0);
> +		ret = -1;
> +		goto exit;
> +	}
> +
> + exit:
> +	return ret;
> +}
> +
> +static void memif_intr_handler(void *arg)
> +{
> +	struct memif_control_channel *cc = arg;
> +	struct rte_eth_dev *dev;
> +	int ret;
> +
> +	ret = memif_msg_receive(cc);
> +	/* if driver failed to assign device */
> +	if (cc->pmd == NULL) {
> +		ret = rte_intr_callback_unregister_pending(&cc->intr_handle,
> +							   memif_intr_handler,
> +							   cc,
> +							   memif_intr_unregister_handler);
> +		if (ret < 0)
> +			MIF_LOG(WARNING,
> +				"Failed to unregister control channel callback.");
> +		return;
> +	}
> +	/* if memif_msg_receive failed */
> +	if (ret < 0)
> +		goto disconnect;
> +
> +	ret = memif_msg_send_from_queue(cc);
> +	if (ret < 0)
> +		goto disconnect;
> +
> +	return;
> +
> + disconnect:
> +	dev = rte_eth_dev_allocated(rte_vdev_device_name(cc->pmd->vdev));
> +	if (dev == NULL) {
> +		MIF_LOG(WARNING, "%s: eth dev not allocated",
> +			rte_vdev_device_name(cc->pmd->vdev));
> +		return;
> +	}
> +	memif_disconnect(dev);
> +}
> +
> +static void memif_listener_handler(void *arg)
> +{
> +	struct memif_socket *socket = arg;
> +	int sockfd;
> +	int addr_len;
> +	struct sockaddr_un client;
> +	struct memif_control_channel *cc;
> +	int ret;
> +
> +	addr_len = sizeof(client);
> +	sockfd = accept(socket->intr_handle.fd, (struct sockaddr *)&client,
> +			(socklen_t *) & addr_len);
> +	if (sockfd < 0) {
> +		MIF_LOG(ERR,
> +			"Failed to accept connection request on socket fd %d",
> +			socket->intr_handle.fd);
> +		return;
> +	}
> +
> +	MIF_LOG(DEBUG, "%s: Connection request accepted.", socket->filename);
> +
> +	cc = rte_zmalloc("memif-cc", sizeof(struct memif_control_channel), 0);
> +	if (cc == NULL) {
> +		MIF_LOG(ERR, "Failed to allocate control channel.");
> +		goto error;
> +	}
> +
> +	cc->intr_handle.fd = sockfd;
> +	cc->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +	cc->socket = socket;
> +	cc->pmd = NULL;
> +	TAILQ_INIT(&cc->msg_queue);
> +
> +	ret =
> +	    rte_intr_callback_register(&cc->intr_handle, memif_intr_handler,
> +				       cc);
> +	if (ret < 0) {
> +		MIF_LOG(ERR, "Failed to register control channel callback.");
> +		goto error;
> +	}
> +
> +	ret = memif_msg_enq_hello(cc);
> +	if (ret < 0) {
> +		MIF_LOG(ERR, "Failed to enqueue hello message.");
> +		goto error;
> +	}
> +	ret = memif_msg_send_from_queue(cc);
> +	if (ret < 0)
> +		goto error;
> +
> +	return;
> +
> + error:
> +	if (sockfd > 0) {
> +		close(sockfd);
> +		sockfd = -1;
> +	}
> +	if (cc != NULL) {
> +		rte_free(cc);
> +		cc = NULL;
> +	}
> +}
> +
> +static inline struct memif_socket *memif_socket_create(struct pmd_internals
> +						       *pmd, char *key,
> +						       uint8_t listener)
> +{
> +	struct memif_socket *sock;
> +	struct sockaddr_un un;
> +	int sockfd;
> +	int ret;
> +	int on = 1;
> +
> +	sock = rte_zmalloc("memif-socket", sizeof(struct memif_socket), 0);
> +	if (sock == NULL) {
> +		MIF_LOG(ERR, "Failed to allocate memory for memif socket");
> +		return NULL;
> +	}
> +
> +	sock->listener = listener;
> +	rte_memcpy(sock->filename, key, 256);
> +	TAILQ_INIT(&sock->pmd_queue);
> +
> +	if (listener != 0) {
> +		sockfd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
> +		if (sockfd < 0)
> +			goto error;;
> +
> +		un.sun_family = AF_UNIX;
> +		strncpy((char *)un.sun_path, (char *)sock->filename,
> +			sizeof(un.sun_path) - 1);
> +
> +		ret = setsockopt(sockfd, SOL_SOCKET, SO_PASSCRED, &on,
> +				 sizeof(on));
> +		if (ret < 0) {
> +			goto error;
> +		}
> +		ret = bind(sockfd, (struct sockaddr *)&un, sizeof(un));
> +		if (ret < 0) {
> +			goto error;
> +		}
> +		ret = listen(sockfd, 1);
> +		if (ret < 0) {
> +			goto error;
> +		}

Single line blocks
> +
> +		MIF_LOG(DEBUG, "%s: Memif listener socket %s created.",
> +			rte_vdev_device_name(pmd->vdev), sock->filename);
> +
> +		sock->intr_handle.fd = sockfd;
> +		sock->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +		ret = rte_intr_callback_register(&sock->intr_handle,
> +						 memif_listener_handler, sock);
> +		if (ret < 0) {
> +			MIF_LOG(ERR, "%s: Failed to register interrupt "
> +				"callback for listener socket",
> +				rte_vdev_device_name(pmd->vdev));
> +			return NULL;
> +		}
> +	}
> +
> +	return sock;
> +
> + error:
> +	MIF_LOG(ERR, "%s: Failed to setup socket %s: %s",
> +		rte_vdev_device_name(pmd->vdev), key, strerror(errno));
> +	if (sock != NULL)
> +		rte_free(sock);
> +	return NULL;
> +}
> +
> +static inline struct rte_hash *memif_create_socket_hash(void)
> +{
> +	struct rte_hash_parameters params = { 0 };
> +	params.name = MEMIF_SOCKET_HASH_NAME;
> +	params.entries = 256;
> +	params.key_len = 256;
> +	params.hash_func = rte_jhash;
> +	params.hash_func_init_val = 0;
> +	return rte_hash_create(&params);
> +}
> +
> +int memif_socket_init(struct rte_eth_dev *dev, const char *socket_filename)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_socket *socket = NULL;
> +	struct memif_socket_pmd_list_elt *elt;
> +	int ret;
> +	char key[256];
> +
> +	struct rte_hash *hash = rte_hash_find_existing(MEMIF_SOCKET_HASH_NAME);
> +	if (hash == NULL) {
> +		hash = memif_create_socket_hash();
> +		if (hash == NULL) {
> +			MIF_LOG(ERR, "Failed to create memif socket hash.");
> +			return -1;
> +		}
> +	}
> +
> +	memset(key, 0, 256);
> +	rte_memcpy(key, socket_filename, strlen(socket_filename));
> +	ret = rte_hash_lookup_data(hash, key, (void **)&socket);
> +	if (ret < 0) {
> +		socket = memif_socket_create(pmd, key,
> +					     (pmd->role ==
> +					      MEMIF_ROLE_SLAVE) ? 0 : 1);
> +		if (socket == NULL) {
> +			return -1;
> +		}
> +		ret = rte_hash_add_key_data(hash, key, socket);
> +		if (ret < 0) {
> +			MIF_LOG(ERR, "Failed to add socket to socket hash.");
> +			return ret;
> +		}
> +	}
> +	pmd->socket_filename = socket->filename;
> +
> +	if ((socket->listener != 0) && (pmd->role == MEMIF_ROLE_SLAVE)) {
> +		MIF_LOG(ERR, "Socket is a listener.");
> +		return -1;
> +	} else if ((socket->listener == 0) && (pmd->role == MEMIF_ROLE_MASTER)) {
> +		MIF_LOG(ERR, "Socket is not a listener.");
> +		return -1;
> +	}
> +
> +	TAILQ_FOREACH(elt, &socket->pmd_queue, next) {
> +		if (elt->pmd->id == pmd->id) {
> +			MIF_LOG(ERR, "Memif device with id %d already "
> +				"exists on socket %s",
> +				pmd->id, socket->filename);
> +			return -1;
> +		}
> +	}
> +
> +	elt =
> +	    rte_malloc("pmd-queue", sizeof(struct memif_socket_pmd_list_elt),
> +		       0);
> +	if (elt == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to add device to socket device list.",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -1;
> +	}
> +	elt->pmd = pmd;
> +	TAILQ_INSERT_TAIL(&socket->pmd_queue, elt, next);
> +
> +	return 0;
> +}
> +
> +void memif_socket_remove_device(struct pmd_internals *pmd)
> +{
> +	struct memif_socket *socket = NULL;
> +	struct memif_socket_pmd_list_elt *elt, *next;
> +
> +	struct rte_hash *hash = rte_hash_find_existing(MEMIF_SOCKET_HASH_NAME);
> +	if (hash == NULL) {
> +		return;
> +	}
> +
> +	if (rte_hash_lookup_data(hash, pmd->socket_filename, (void **)&socket) <
> +	    0)
> +		return;
> +
> +	for (elt = TAILQ_FIRST(&socket->pmd_queue); elt != NULL; elt = next) {
> +		next = TAILQ_NEXT(elt, next);
> +		if (elt->pmd == pmd) {
> +			TAILQ_REMOVE(&socket->pmd_queue, elt, next);
> +			free(elt);
> +			pmd->socket_filename = NULL;
> +		}
> +	}
> +
> +	/* remove socket, if this was the last device using it */
> +	if (TAILQ_EMPTY(&socket->pmd_queue)) {
> +		rte_hash_del_key(hash, socket->filename);
> +		if (socket->listener) {
> +			/* remove listener socket file,
> +			 * so we can create new one later.
> +			 */
> +			remove(socket->filename);
> +		}
> +		rte_free(socket);
> +	}
> +}
> +
> +int memif_connect_master(struct rte_eth_dev *dev)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	if ((pmd->rx_queues == NULL) || (pmd->tx_queues == NULL) ||
> +	    (pmd->socket_filename == NULL)) {
> +		MIF_LOG(ERR, "%s: Device not configured!",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -1;
> +	}
> +	memset(pmd->local_disc_string, 0, 96);
> +	memset(pmd->remote_disc_string, 0, 96);
> +	pmd->flags &= ~ETH_MEMIF_FLAG_DISABLED;
> +	return 0;
> +}
> +
> +int memif_connect_slave(struct rte_eth_dev *dev)
> +{
> +	int sockfd;
> +	int ret;
> +	struct sockaddr_un sun;
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +
> +	if ((pmd->rx_queues == NULL) || (pmd->tx_queues == NULL) ||
> +	    (pmd->socket_filename == NULL)) {
> +		MIF_LOG(ERR, "%s: Device not configured!",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -1;
> +	}
> +
> +	memset(pmd->local_disc_string, 0, 96);
> +	memset(pmd->remote_disc_string, 0, 96);
> +	pmd->flags &= ~ETH_MEMIF_FLAG_DISABLED;
> +
> +	sockfd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
> +	if (sockfd < 0) {
> +		MIF_LOG(ERR, "%s: Failed to open socket.",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -1;
> +	}
> +
> +	sun.sun_family = AF_UNIX;
> +
> +	strncpy(sun.sun_path, pmd->socket_filename, sizeof(sun.sun_path) - 1);
> +
> +	ret = connect(sockfd, (struct sockaddr *)&sun,
> +		      sizeof(struct sockaddr_un));
> +	if (ret < 0) {
> +		MIF_LOG(ERR, "%s: Failed to connect socket: %s.",
> +			rte_vdev_device_name(pmd->vdev), pmd->socket_filename);
> +		goto error;
> +	}
> +
> +	MIF_LOG(DEBUG, "%s: Memif socket: %s connected.",
> +		rte_vdev_device_name(pmd->vdev), pmd->socket_filename);
> +
> +	pmd->cc = rte_zmalloc("memif-cc",
> +			      sizeof(struct memif_control_channel), 0);
> +	if (pmd->cc == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to allocate control channel.",
> +			rte_vdev_device_name(pmd->vdev));
> +		goto error;
> +	}
> +
> +	pmd->cc->intr_handle.fd = sockfd;
> +	pmd->cc->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +	pmd->cc->socket = NULL;
> +	pmd->cc->pmd = pmd;
> +	TAILQ_INIT(&pmd->cc->msg_queue);
> +
> +	ret = rte_intr_callback_register(&pmd->cc->intr_handle,
> +					 memif_intr_handler, pmd->cc);
> +	if (ret < 0) {
> +		MIF_LOG(ERR, "%s: Failed to register interrupt callback "
> +			"for controll fd", rte_vdev_device_name(pmd->vdev));
> +		goto error;
> +	}
> +
> +	return 0;
> +
> + error:
> +	if (sockfd > 0) {
> +		close(sockfd);
> +		sockfd = -1;
> +	}
> +	if (pmd->cc != NULL) {
> +		rte_free(pmd->cc);
> +		pmd->cc = NULL;
> +	}
> +	return -1;
> +}
> diff --git a/drivers/net/memif/memif_socket.h b/drivers/net/memif/memif_socket.h
> new file mode 100644
> index 000000000..f9136dbe5
> --- /dev/null
> +++ b/drivers/net/memif/memif_socket.h
> @@ -0,0 +1,57 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#ifndef _MEMIF_SOCKET_H_
> +#define _MEMIF_SOCKET_H_
> +
> +#include <sys/queue.h>
> +
> +/*
> + * Remove device from socket device list. If no device is left on the socket,
> + * remove the socket as well.
> + */
> +void memif_socket_remove_device(struct pmd_internals *pmd);
> +
> +void memif_msg_enq_disconnect(struct memif_control_channel *cc,
> +			      const char *reason, int err_code);
> +
> +int memif_socket_init(struct rte_eth_dev *dev, const char *socket_filename);
> +
> +void memif_disconnect(struct rte_eth_dev *dev);
> +
> +/* Allow master to receive connection requests. */
> +int memif_connect_master(struct rte_eth_dev *dev);
> +
> +/* Send connection request. */
> +int memif_connect_slave(struct rte_eth_dev *dev);

We document functions in the header file before the declare using Doxygen formatting

/**
 * One line description
 *
 * More description if needed (optional)
 *
 * @param foo1
 *    Description of argument
 * @param foo2
 *    Description of argument
 * @return (only if function returns something, but could be N/A)
 *    Desciption of return value(s)
 */
int
Function(int foo1, int foo2)
{
	return foo1 + foo2;
}

> +
> +struct memif_socket_pmd_list_elt {
> +	TAILQ_ENTRY(memif_socket_pmd_list_elt) next;
> +	struct pmd_internals *pmd;
> +};
> +
> +#define MEMIF_SOCKET_HASH_NAME			"memif-sh"
> +struct memif_socket {
> +	struct rte_intr_handle intr_handle;
> +	uint8_t listener;
> +	char filename[256];
> +
> +	 TAILQ_HEAD(, memif_socket_pmd_list_elt) pmd_queue;

Odd spacing see below
> +};
> +
> +/* Control mesage queue. */
> +struct memif_msg_queue_elt {
> +	TAILQ_ENTRY(memif_msg_queue_elt) next;
> +	memif_msg_t msg;
> +	int fd;
> +};
> +
> +struct memif_control_channel {
> +	struct rte_intr_handle intr_handle;
> +	 TAILQ_HEAD(, memif_msg_queue_elt) msg_queue;

Odd spacing above, maybe a space and tab problem. We use tabs of 8 first then align with spaces.
> +	struct memif_socket *socket;
> +	struct pmd_internals *pmd;
> +};
> +
> +#endif				/* MEMIF_SOCKET_H */
> diff --git a/drivers/net/memif/meson.build b/drivers/net/memif/meson.build
> new file mode 100644
> index 000000000..ea18394fd
> --- /dev/null
> +++ b/drivers/net/memif/meson.build
> @@ -0,0 +1,8 @@
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> +
> +if host_machine.system() != 'linux'
> +        build = false
> +endif
> +sources = files('rte_eth_memif.c',
> +		'memif_socket.c')
> diff --git a/drivers/net/memif/rte_eth_memif.c b/drivers/net/memif/rte_eth_memif.c
> new file mode 100644
> index 000000000..7988010c4
> --- /dev/null
> +++ b/drivers/net/memif/rte_eth_memif.c
> @@ -0,0 +1,1172 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#include <stdlib.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <sys/types.h>
> +#include <sys/socket.h>
> +#include <sys/un.h>
> +#include <sys/ioctl.h>
> +#include <sys/mman.h>
> +#include <linux/if_ether.h>
> +#include <errno.h>
> +#include <sys/eventfd.h>
> +
> +#include <rte_version.h>
> +#include <rte_mbuf.h>
> +#include <rte_ether.h>
> +#include <rte_ethdev_driver.h>
> +#include <rte_ethdev_vdev.h>
> +#include <rte_malloc.h>
> +#include <rte_kvargs.h>
> +#include <rte_bus_vdev.h>
> +
> +#include <rte_eth_memif.h>
> +#include <memif_socket.h>
> +
> +#define ETH_MEMIF_ID_ARG		"id"
> +#define ETH_MEMIF_ROLE_ARG		"role"
> +#define ETH_MEMIF_BUFFER_SIZE_ARG	"bsize"
> +#define ETH_MEMIF_RING_SIZE_ARG		"rsize"
> +#define ETH_MEMIF_NRXQ_ARG		"nrxq"
> +#define ETH_MEMIF_NTXQ_ARG		"ntxq"
> +#define ETH_MEMIF_SOCKET_ARG		"socket"
> +#define ETH_MEMIF_MAC_ARG		"mac"
> +#define ETH_MEMIF_ZC_ARG		"zero-copy"
> +#define ETH_MEMIF_SECRET_ARG		"secret"
> +
> +static const char *valid_arguments[] = {
> +	ETH_MEMIF_ID_ARG,
> +	ETH_MEMIF_ROLE_ARG,
> +	ETH_MEMIF_BUFFER_SIZE_ARG,
> +	ETH_MEMIF_RING_SIZE_ARG,
> +	ETH_MEMIF_NRXQ_ARG,
> +	ETH_MEMIF_NTXQ_ARG,
> +	ETH_MEMIF_SOCKET_ARG,
> +	ETH_MEMIF_MAC_ARG,
> +	ETH_MEMIF_ZC_ARG,
> +	ETH_MEMIF_SECRET_ARG,
> +	NULL
> +};
> +
> +static struct rte_vdev_driver pmd_memif_drv;
> +
> +const char *memif_version(void)
> +{
> +#define STR_HELP(s)	#s
> +#define STR(s)		STR_HELP(s)
> +	return ("memif-" STR(MEMIF_VERSION_MAJOR) "." STR(MEMIF_VERSION_MINOR));
> +#undef STR
> +#undef STR_HELP
> +}
> +
> +static void
> +memif_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +
> +	dev_info->if_index = pmd->if_index;
> +	dev_info->max_mac_addrs = 1;
> +	dev_info->max_rx_pktlen = (uint32_t) ETH_FRAME_LEN;
> +	dev_info->max_rx_queues = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +	    pmd->cfg.num_m2s_rings : pmd->cfg.num_s2m_rings;
> +	dev_info->max_tx_queues = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +	    pmd->cfg.num_s2m_rings : pmd->cfg.num_m2s_rings;
> +	dev_info->min_rx_bufsize = 0;
> +}
> +
> +static inline memif_ring_t *memif_get_ring(struct pmd_internals *pmd,
> +					   memif_ring_type_t type,
> +					   uint16_t ring_num)
> +{
> +	/* rings only in region 0 */
> +	void *p = pmd->regions[0].addr;
> +	int ring_size = sizeof(memif_ring_t) + sizeof(memif_desc_t) *
> +	    (1 << pmd->run.log2_ring_size);
> +	p += (ring_num + type * pmd->run.num_s2m_rings) * ring_size;
> +
> +	return (memif_ring_t *) p;
> +}
> +
> +static inline void *memif_get_buffer(struct pmd_internals *pmd,
> +				     memif_desc_t * d)
> +{
> +	return (pmd->regions[d->region].addr + d->offset);
> +}
> +
> +static uint16_t
> +eth_memif_rx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
> +{
> +	struct memif_queue *mq = queue;
> +	struct pmd_internals *pmd = mq->pmd;
> +	if (unlikely((pmd->flags & ETH_MEMIF_FLAG_CONNECTED) == 0))
> +		return 0;
> +	memif_ring_t *ring = mq->ring;
> +	if (unlikely(ring == NULL))
> +		return 0;
> +	uint16_t cur_slot, last_slot, n_slots, ring_size, mask, s0;
> +	uint16_t n_rx_pkts = 0;
> +	uint16_t mbuf_size = rte_pktmbuf_data_room_size(mq->mempool) -
> +	    RTE_PKTMBUF_HEADROOM;
> +	uint16_t src_len, src_off, dst_len, dst_off, cp_len;
> +	memif_ring_type_t type = mq->type;
> +	memif_desc_t *d0;
> +	struct rte_mbuf *mbuf;
> +	struct rte_mbuf *mbuf_head = NULL;
> +
> +	/* consume interrupt */
> +	if ((ring->flags & MEMIF_RING_FLAG_MASK_INT) == 0) {
> +		uint64_t b;
> +		ssize_t size __rte_unused;
> +		size = read(mq->intr_handle.fd, &b, sizeof(b));
> +	}
> +
> +	ring_size = 1 << mq->log2_ring_size;
> +	mask = ring_size - 1;
> +
> +	cur_slot = (type == MEMIF_RING_S2M) ? mq->last_head : mq->last_tail;
> +	last_slot = (type == MEMIF_RING_S2M) ? ring->head : ring->tail;
> +	if (cur_slot == last_slot)
> +		goto refill;
> +	n_slots = last_slot - cur_slot;
> +
> +	while (n_slots && n_rx_pkts < nb_pkts) {
> +		mbuf_head = rte_pktmbuf_alloc(mq->mempool);
> +		if (unlikely(mbuf_head == NULL))
> +			goto no_free_bufs;
> +		mbuf = mbuf_head;
> +		mbuf->port = mq->in_port;
> +
> + next_slot:
> +		s0 = cur_slot & mask;
> +		d0 = &ring->desc[s0];
> +
> +		src_len = d0->length;
> +		dst_off = 0;
> +		src_off = 0;
> +
> +		do {
> +			dst_len = mbuf_size - dst_off;
> +			if (dst_len == 0) {
> +				dst_off = 0;
> +				dst_len = mbuf_size + RTE_PKTMBUF_HEADROOM;
> +
> +				mbuf = rte_pktmbuf_alloc(mq->mempool);
> +				if (unlikely(mbuf == NULL))
> +					goto no_free_bufs;
> +				mbuf->port = mq->in_port;
> +				rte_pktmbuf_chain(mbuf_head, mbuf);
> +			}
> +			cp_len = memif_min(dst_len, src_len);
> +
> +			rte_pktmbuf_pkt_len(mbuf) =
> +			    rte_pktmbuf_data_len(mbuf) += cp_len;
> +
> +			memcpy(rte_pktmbuf_mtod_offset(mbuf, void *, dst_off),
> +			       memif_get_buffer(pmd, d0) + src_off, cp_len);
> +
> +			mq->n_bytes += cp_len;
> +			src_off += cp_len;
> +			dst_off += cp_len;
> +			src_len -= cp_len;
> +		} while (src_len);
> +
> +		cur_slot++;
> +		n_slots--;
> +		if (d0->flags & MEMIF_DESC_FLAG_NEXT) {
> +			goto next_slot;
> +		}

Single line block
> +
> +		*bufs++ = mbuf_head;
> +		n_rx_pkts++;
> +
> +	}
> +
> + no_free_bufs:
> +	if (type == MEMIF_RING_S2M) {
> +		rte_mb();
> +		ring->tail = mq->last_head = cur_slot;
> +	} else {
> +		mq->last_tail = cur_slot;
> +	}
> +
 Single line block
> + refill:
> +	if (type == MEMIF_RING_M2S) {
> +		uint16_t head = ring->head;
> +		n_slots = ring_size - head + mq->last_tail;
> +
> +		while (n_slots--) {
> +			s0 = head++ & mask;
> +			d0 = &ring->desc[s0];
> +			d0->length = pmd->run.buffer_size;
> +		}
> +		rte_mb();
> +		ring->head = head;
> +	}
> +
> +	mq->n_pkts += n_rx_pkts;
> +	return n_rx_pkts;
> +}
> +
> +static uint16_t
> +eth_memif_tx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
> +{
> +	struct memif_queue *mq = queue;
> +	struct pmd_internals *pmd = mq->pmd;
> +	if (unlikely((pmd->flags & ETH_MEMIF_FLAG_CONNECTED) == 0))
> +		return 0;
> +	memif_ring_t *ring = mq->ring;
> +	if (unlikely(ring == NULL))
> +		return 0;
> +	uint16_t slot, saved_slot, n_free, ring_size, mask, n_tx_pkts = 0;
> +	uint16_t src_len, src_off, dst_len, dst_off, cp_len;
> +	memif_ring_type_t type = mq->type;
> +	memif_desc_t *d0;
> +	struct rte_mbuf *mbuf;
> +	struct rte_mbuf *mbuf_head;
> +
> +	ring_size = 1 << mq->log2_ring_size;
> +	mask = ring_size - 1;
> +
> +	n_free = ring->tail - mq->last_tail;
> +	mq->last_tail += n_free;
> +	slot = (type == MEMIF_RING_S2M) ? ring->head : ring->tail;
> +
> +	if (type == MEMIF_RING_S2M)
> +		n_free = ring_size - ring->head + mq->last_tail;
> +	else
> +		n_free = ring->head - ring->tail;
> +
> +	while (n_free && n_tx_pkts < nb_pkts) {
> +		mbuf_head = *bufs++;
> +		mbuf = mbuf_head;
> +
> +		saved_slot = slot;
> +		d0 = &ring->desc[slot & mask];
> +		dst_off = 0;
> +		dst_len =
> +		    (type ==
> +		     MEMIF_RING_S2M) ? pmd->run.buffer_size : d0->length;
> +
> + next_in_chain:
> +		src_off = 0;
> +		src_len = rte_pktmbuf_data_len(mbuf);
> +
> +		while (src_len) {
> +			if (dst_len == 0) {
> +				if (n_free) {
> +					slot++;
> +					n_free--;
> +					d0->flags |= MEMIF_DESC_FLAG_NEXT;
> +					d0 = &ring->desc[slot & mask];
> +					dst_off = 0;
> +					dst_len = (type == MEMIF_RING_S2M) ?
> +					    pmd->run.buffer_size : d0->length;
> +					d0->flags = 0;
> +				} else {
> +					slot = saved_slot;
> +					goto no_free_slots;
> +				}
> +			}
> +			cp_len = memif_min(dst_len, src_len);
> +
> +			memcpy(memif_get_buffer(pmd, d0) + dst_off,
> +			       rte_pktmbuf_mtod_offset(mbuf, void *, src_off),
> +			       cp_len);
> +
> +			mq->n_bytes += cp_len;
> +			src_off += cp_len;
> +			dst_off += cp_len;
> +			src_len -= cp_len;
> +			dst_len -= cp_len;
> +
> +			d0->length = dst_off;
> +		}
> +
> +		if (rte_pktmbuf_is_contiguous(mbuf) == 0) {
> +			mbuf = mbuf->next;
> +			goto next_in_chain;
> +		}
> +
> +		n_tx_pkts++;
> +		slot++;
> +		n_free--;
> +		rte_pktmbuf_free(mbuf_head);
> +	}
> +
> + no_free_slots:
> +	rte_mb();
> +	if (type == MEMIF_RING_S2M)
> +		ring->head = slot;
> +	else
> +		ring->tail = slot;
> +
> +	if ((ring->flags & MEMIF_RING_FLAG_MASK_INT) == 0) {
> +		uint64_t a = 1;
> +		ssize_t size = write(mq->intr_handle.fd, &a, sizeof(a));
> +		if (unlikely(size < 0)) {
> +			MIF_LOG(WARNING,
> +				"%s: Failed to send interrupt on qid %ld: %s",
> +				rte_vdev_device_name(pmd->vdev),
> +				mq - pmd->tx_queues, strerror(errno));
> +		}
> +	}
> +
> +	mq->n_err += nb_pkts - n_tx_pkts;
> +	mq->n_pkts += n_tx_pkts;
> +	return n_tx_pkts;
> +}
> +
> +void memif_free_regions(struct pmd_internals *pmd)
> +{
> +	int i;
> +	struct memif_region *r;
> +
> +	for (i = 0; i < pmd->regions_num; i++) {
> +		r = pmd->regions + i;
> +		if (r == NULL)
> +			return;
> +		if (r->addr == NULL)
> +			return;
> +		munmap(r->addr, r->region_size);
> +		if (r->fd > 0) {
> +			close(r->fd);
> +			r->fd = -1;
> +		}
> +	}
> +	rte_free(pmd->regions);
> +}
> +
> +static int memif_alloc_regions(struct pmd_internals *pmd, uint8_t brn)
> +{
> +	struct memif_region *r;
> +	char shm_name[32];
> +	int i;
> +	int ret = 0;
> +
> +	r = rte_zmalloc("memif_region", sizeof(struct memif_region) * (brn + 1),
> +			0);
> +	if (r == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to allocate regions.",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -ENOMEM;
> +	}
> +
> +	pmd->regions = r;
> +	pmd->regions_num = brn + 1;
> +
> +	/*
> +	 * Create shm for every region. Region 0 is reserved for descriptors.
> +	 * Other regions contain buffers.
> +	 */
> +	for (i = 0; i < (brn + 1); i++) {
> +		r = &pmd->regions[i];
> +
> +		r->buffer_offset = (i == 0) ? (pmd->run.num_s2m_rings +
> +					       pmd->run.num_m2s_rings) *
> +		    (sizeof(memif_ring_t) +
> +		     sizeof(memif_desc_t) * (1 << pmd->run.log2_ring_size)) : 0;
> +		r->region_size = (i == 0) ? r->buffer_offset :
> +		    (uint32_t) (pmd->run.buffer_size *
> +				(1 << pmd->run.log2_ring_size) *
> +				(pmd->run.num_s2m_rings +
> +				 pmd->run.num_m2s_rings));
> +
> +		memset(shm_name, 0, sizeof(char) * 32);
> +		sprintf(shm_name, "memif region %d", i);
> +
> +		r->fd = memfd_create(shm_name, MFD_ALLOW_SEALING);
> +		if (r->fd < 0) {
> +			MIF_LOG(ERR, "%s: Failed to create shm file: %s.",
> +				rte_vdev_device_name(pmd->vdev),
> +				strerror(errno));
> +			return -1;
> +		}
> +
> +		ret = fcntl(r->fd, F_ADD_SEALS, F_SEAL_SHRINK);
> +		if (ret < 0) {
> +			MIF_LOG(ERR, "%s: Failed to add seals to shm file: %s.",
> +				rte_vdev_device_name(pmd->vdev),
> +				strerror(errno));
> +			return -1;
> +		}
> +
> +		ret = ftruncate(r->fd, r->region_size);
> +		if (ret < 0) {
> +			MIF_LOG(ERR, "%s: Failed to truncate shm file: %s.",
> +				rte_vdev_device_name(pmd->vdev),
> +				strerror(errno));
> +			return -1;
> +		}
> +
> +		r->addr = mmap(NULL, r->region_size, PROT_READ |
> +			       PROT_WRITE, MAP_SHARED, r->fd, 0);
> +		if (r->addr == NULL) {
> +			MIF_LOG(ERR, "%s: Failed to mmap shm region: %s.",
> +				rte_vdev_device_name(pmd->vdev),
> +				strerror(errno));
> +			return -1;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static void memif_init_rings(struct pmd_internals *pmd)
> +{
> +	memif_ring_t *ring;
> +	int i, j;
> +
> +	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
> +		ring = memif_get_ring(pmd, MEMIF_RING_S2M, i);
> +		ring->head = ring->tail = 0;
> +		ring->cookie = MEMIF_COOKIE;
> +		ring->flags = 0;
> +		for (j = 0; j < (1 << pmd->run.log2_ring_size); j++) {
> +			uint16_t slot = i * (1 << pmd->run.log2_ring_size) + j;
> +			ring->desc[j].region = 1;
> +			ring->desc[j].offset = pmd->regions[1].buffer_offset +
> +			    (uint32_t) (slot * pmd->run.buffer_size);
> +			ring->desc[j].length = pmd->run.buffer_size;
> +		}
> +	}
> +
> +	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
> +		ring = memif_get_ring(pmd, MEMIF_RING_M2S, i);
> +		ring->head = ring->tail = 0;
> +		ring->cookie = MEMIF_COOKIE;
> +		ring->flags = 0;
> +		for (j = 0; j < (1 << pmd->run.log2_ring_size); j++) {
> +			uint16_t slot = (i + pmd->run.num_s2m_rings) *
> +			    (1 << pmd->run.log2_ring_size) + j;
> +			ring->desc[j].region = 1;
> +			ring->desc[j].offset = pmd->regions[1].buffer_offset +
> +			    (uint32_t) (slot * pmd->run.buffer_size);
> +			ring->desc[j].length = pmd->run.buffer_size;
> +		}
> +	}
> +}
> +
> +static void memif_init_queues(struct pmd_internals *pmd)
> +{
> +	struct memif_queue *mq;
> +	int i;
> +
> +	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
> +		mq = &pmd->tx_queues[i];
> +		mq->ring = memif_get_ring(pmd, MEMIF_RING_S2M, i);
> +		mq->log2_ring_size = pmd->run.log2_ring_size;
> +		/* queues located only in region 0 */
> +		mq->region = 0;
> +		mq->offset = (void *)mq->ring - (void *)pmd->regions[0].addr;
> +		mq->last_head = mq->last_tail = 0;
> +		mq->intr_handle.fd = eventfd(0, EFD_NONBLOCK);
> +		if (mq->intr_handle.fd < 0) {
> +			MIF_LOG(WARNING,
> +				"%s: Failed to create eventfd for tx queue %d: %s.",
> +				rte_vdev_device_name(pmd->vdev), i,
> +				strerror(errno));
> +		}
> +	}
> +
> +	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
> +		mq = &pmd->rx_queues[i];
> +		mq->ring = memif_get_ring(pmd, MEMIF_RING_M2S, i);
> +		mq->log2_ring_size = pmd->run.log2_ring_size;
> +		/* queues located only in region 0 */
> +		mq->region = 0;
> +		mq->offset = (void *)mq->ring - (void *)pmd->regions[0].addr;
> +		mq->last_head = mq->last_tail = 0;
> +		mq->intr_handle.fd = eventfd(0, EFD_NONBLOCK);
> +		if (mq->intr_handle.fd < 0) {
> +			MIF_LOG(WARNING,
> +				"%s: Failed to create eventfd for rx queue %d: %s.",
> +				rte_vdev_device_name(pmd->vdev), i,
> +				strerror(errno));
> +		}
> +	}
> +}
> +
> +int memif_init_regions_and_queues(struct pmd_internals *pmd)
> +{
> +	int ret;
> +
> +	ret = memif_alloc_regions(pmd, /* num of buffer regions */ 1);
> +	if (ret < 0) {
> +		return ret;
> +	}

Single line block
> +
> +	memif_init_rings(pmd);
> +
> +	memif_init_queues(pmd);
> +
> +	return 0;
> +}
> +
> +int memif_connect(struct pmd_internals *pmd)
> +{
> +	struct rte_eth_dev *eth_dev =
> +	    rte_eth_dev_allocated(rte_vdev_device_name(pmd->vdev));
> +	struct memif_region *mr;
> +	struct memif_queue *mq;
> +	int i;
> +
> +	for (i = 0; i < pmd->regions_num; i++) {
> +		mr = pmd->regions + i;
> +		if (mr != NULL) {
> +			if (mr->addr == NULL) {
> +				if (mr->fd < 0)
> +					return -1;
> +				mr->addr = mmap(NULL, mr->region_size,
> +						PROT_READ | PROT_WRITE,
> +						MAP_SHARED, mr->fd, 0);
> +				if (mr->addr == NULL)
> +					return -1;
> +			}
> +		}
> +	}
> +
> +	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +		    &pmd->tx_queues[i] : &pmd->rx_queues[i];
> +		mq->ring = pmd->regions[mq->region].addr + mq->offset;
> +		if (mq->ring->cookie != MEMIF_COOKIE) {
> +			MIF_LOG(ERR, "%s: Wrong cookie",
> +				rte_vdev_device_name(pmd->vdev));
> +			return -1;
> +		}
> +		mq->ring->head = mq->ring->tail = mq->last_head =
> +		    mq->last_tail = 0;
> +		/* polling mode by default */
> +		if (pmd->role == MEMIF_ROLE_MASTER) {
> +			mq->ring->flags = MEMIF_RING_FLAG_MASK_INT;
> +		}
> +	}
> +	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +		    &pmd->rx_queues[i] : &pmd->tx_queues[i];
> +		mq->ring = pmd->regions[mq->region].addr + mq->offset;
> +		if (mq->ring->cookie != MEMIF_COOKIE) {
> +			MIF_LOG(ERR, "%s: Wrong cookie",
> +				rte_vdev_device_name(pmd->vdev));
> +			return -1;
> +		}
> +		mq->ring->head = mq->ring->tail = mq->last_head =
> +		    mq->last_tail = 0;
> +		/* polling mode by default */
> +		if (pmd->role == MEMIF_ROLE_SLAVE) {
> +			mq->ring->flags = MEMIF_RING_FLAG_MASK_INT;
> +		}
> +	}
> +
> +	pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTING;
> +	pmd->flags |= ETH_MEMIF_FLAG_CONNECTED;
> +	eth_dev->data->dev_link.link_status = ETH_LINK_UP;
> +	MIF_LOG(INFO, "%s: Connected.", rte_vdev_device_name(pmd->vdev));
> +	return 0;
> +}
> +
> +static int memif_dev_start(struct rte_eth_dev *dev)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	int ret = 0;
> +
> +	switch (pmd->role) {
> +	case MEMIF_ROLE_SLAVE:
> +		ret = memif_connect_slave(dev);
> +		break;
> +	case MEMIF_ROLE_MASTER:
> +		ret = memif_connect_master(dev);
> +		break;
> +	default:
> +		MIF_LOG(ERR, "%s: Unknown role: %d.",
> +			rte_vdev_device_name(pmd->vdev), pmd->role);
> +		ret = -1;
> +		break;
> +	}
> +
> +	return ret;
> +}
> +
> +static int memif_dev_configure(struct rte_eth_dev *dev __rte_unused)
> +{
> +	return 0;
> +}
> +
> +static int
> +memif_tx_queue_setup(struct rte_eth_dev *dev,
> +		     uint16_t qid,
> +		     uint16_t nb_tx_desc __rte_unused,
> +		     unsigned int socket_id __rte_unused,
> +		     const struct rte_eth_txconf *tx_conf __rte_unused)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_queue *mq;
> +
> +	mq = rte_realloc(pmd->tx_queues, sizeof(struct memif_queue) * (qid + 1),
> +			 0);
> +	if (mq == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to alloc tx queue %u.",
> +			rte_vdev_device_name(pmd->vdev), qid);
> +		return -ENOMEM;
> +	}
> +
> +	pmd->tx_queues = mq;
> +
> +	mq->type =
> +	    (pmd->role == MEMIF_ROLE_SLAVE) ? MEMIF_RING_S2M : MEMIF_RING_M2S;
> +	mq->n_pkts = 0;
> +	mq->n_bytes = 0;
> +	mq->n_err = 0;
> +	mq->intr_handle.fd = -1;
> +	mq->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +	mq->pmd = pmd;
> +	dev->data->tx_queues[qid] = mq;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_rx_queue_setup(struct rte_eth_dev *dev,
> +		     uint16_t qid,
> +		     uint16_t nb_rx_desc __rte_unused,
> +		     unsigned int socket_id __rte_unused,
> +		     const struct rte_eth_rxconf *rx_conf __rte_unused,
> +		     struct rte_mempool *mb_pool)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_queue *mq;
> +
> +	mq = rte_realloc(pmd->rx_queues, sizeof(struct memif_queue) * (qid + 1),
> +			 0);
> +	if (mq == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to alloc rx queue %u.",
> +			rte_vdev_device_name(pmd->vdev), qid);
> +		return -ENOMEM;
> +	}
> +
> +	pmd->rx_queues = mq;
> +
> +	mq->type =
> +	    (pmd->role == MEMIF_ROLE_SLAVE) ? MEMIF_RING_M2S : MEMIF_RING_S2M;
> +	mq->n_pkts = 0;
> +	mq->n_bytes = 0;
> +	mq->n_err = 0;
> +	mq->intr_handle.fd = -1;
> +	mq->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +	mq->mempool = mb_pool;
> +	mq->in_port = dev->data->port_id;
> +	mq->pmd = pmd;
> +	dev->data->rx_queues[qid] = mq;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_link_update(struct rte_eth_dev *dev __rte_unused,
> +		  int wait_to_complete __rte_unused)
> +{
> +	return 0;
> +}
> +
> +static int memif_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *stats)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_queue *mq;
> +	int i;
> +
> +	stats->ipackets = 0;
> +	stats->ibytes = 0;
> +	stats->opackets = 0;
> +	stats->obytes = 0;
> +	stats->oerrors = 0;
> +
> +	uint8_t tmp = (pmd->role == MEMIF_ROLE_SLAVE) ? pmd->run.num_s2m_rings :
> +	    pmd->run.num_m2s_rings;
> +	uint8_t nq = (tmp < RTE_ETHDEV_QUEUE_STAT_CNTRS) ? tmp :
> +	    RTE_ETHDEV_QUEUE_STAT_CNTRS;
> +
> +	/* RX stats */
> +	for (i = 0; i < nq; i++) {
> +		mq = &pmd->rx_queues[i];
> +		stats->q_ipackets[i] = mq->n_pkts;
> +		stats->q_ibytes[i] = mq->n_bytes;
> +		stats->ipackets += mq->n_pkts;
> +		stats->ibytes += mq->n_bytes;
> +	}
> +
> +	tmp = (pmd->role == MEMIF_ROLE_SLAVE) ? pmd->run.num_m2s_rings :
> +	    pmd->run.num_s2m_rings;
> +	nq = (tmp < RTE_ETHDEV_QUEUE_STAT_CNTRS) ? tmp :
> +	    RTE_ETHDEV_QUEUE_STAT_CNTRS;
> +
> +	/* TX stats */
> +	for (i = 0; i < nq; i++) {
> +		mq = &pmd->tx_queues[i];
> +		stats->q_opackets[i] = mq->n_pkts;
> +		stats->q_obytes[i] = mq->n_bytes;
> +		stats->q_errors[i] = mq->n_err;
> +		stats->opackets += mq->n_pkts;
> +		stats->obytes += mq->n_bytes;
> +		stats->oerrors += mq->n_err;
> +	}
> +	return 0;
> +}
> +
> +static void memif_stats_reset(struct rte_eth_dev *dev)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	int i;
> +	struct memif_queue *mq;
> +
> +	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ? &pmd->tx_queues[i] :
> +		    &pmd->rx_queues[i];
> +		mq->n_pkts = 0;
> +		mq->n_bytes = 0;
> +		mq->n_err = 0;
> +	}
> +	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ? &pmd->rx_queues[i] :
> +		    &pmd->tx_queues[i];
> +		mq->n_pkts = 0;
> +		mq->n_bytes = 0;
> +		mq->n_err = 0;
> +	}
> +}
> +
> +static int
> +memif_rx_queue_intr_enable(struct rte_eth_dev *dev, uint16_t qid __rte_unused)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +
> +	MIF_LOG(WARNING, "%s: Interrupt mode not supported.",
> +		rte_vdev_device_name(pmd->vdev));
> +
> +	/* Enable MEMIF interrupts. */
> +	/* pmd->rx_queues[qid].ring->flags  &= ~MEMIF_RING_FLAG_MASK_INT; */
> +
> +	/*
> +	 * TODO: Tell dpdk to use interrupt mode.
> +	 *
> +	 * return rte_intr_enable(&pmd->rx_queues[qid].intr_handle);
> +	 */
> +	return -1;
> +}
> +
> +static int
> +memif_rx_queue_intr_disable(struct rte_eth_dev *dev, uint16_t qid __rte_unused)
> +{
> +	struct pmd_internals *pmd __rte_unused = dev->data->dev_private;
> +
> +	/* Disable MEMIF interrupts. */
> +	/* pmd->rx_queues[qid].ring->flags |= MEMIF_RING_FLAG_MASK_INT; */
> +
> +	/*
> +	 * TODO: Tell dpdk to use polling mode.
> +	 *
> +	 * return rte_intr_disable(&pmd->rx_queues[qid].intr_handle);
> +	 */
> +	return 0;
> +}
> +
> +static const struct eth_dev_ops ops = {
> +	.dev_start = memif_dev_start,
> +	.dev_infos_get = memif_dev_info,
> +	.dev_configure = memif_dev_configure,
> +	.tx_queue_setup = memif_tx_queue_setup,
> +	.rx_queue_setup = memif_rx_queue_setup,
> +	.rx_queue_intr_enable = memif_rx_queue_intr_enable,
> +	.rx_queue_intr_disable = memif_rx_queue_intr_disable,
> +	.link_update = memif_link_update,
> +	.stats_get = memif_stats_get,
> +	.stats_reset = memif_stats_reset,
> +};
> +
> +static int
> +memif_create(struct rte_vdev_device *vdev, enum memif_role_t role,
> +	     memif_interface_id_t id, uint32_t flags,
> +	     const char *socket_filename,
> +	     memif_log2_ring_size_t log2_ring_size, uint8_t nrxq,
> +	     uint8_t ntxq, uint16_t buffer_size, const char *secret,
> +	     const char *eth_addr)
> +{
> +	int ret = 0;
> +	struct rte_eth_dev *eth_dev;
> +	struct rte_eth_dev_data *data;
> +	struct pmd_internals *pmd;
> +	const unsigned int numa_node = vdev->device.numa_node;
> +	const char *name = rte_vdev_device_name(vdev);
> +
> +	if (flags & ETH_MEMIF_FLAG_ZERO_COPY) {
> +		MIF_LOG(ERR, "Zero-copy not supported.");
> +		return -1;
> +	}
> +
> +	eth_dev = rte_eth_vdev_allocate(vdev, sizeof(*pmd));
> +	if (eth_dev == NULL) {
> +		MIF_LOG(ERR, "%s: Unable to allocate device struct.", name);
> +		return -1;
> +	}
> +
> +	pmd = eth_dev->data->dev_private;
> +	memset(pmd, 0, sizeof(*pmd));
> +
> +	pmd->if_index = id;
> +	pmd->vdev = vdev;
> +	pmd->id = id;
> +	pmd->flags = flags;
> +	pmd->flags |= ETH_MEMIF_FLAG_DISABLED;
> +	pmd->role = role;
> +	ret = memif_socket_init(eth_dev, socket_filename);
> +	if (ret < 0)
> +		return ret;
> +
> +	memset(pmd->secret, 0, sizeof(char) * 24);
> +	if (secret != NULL)
> +		strncpy(pmd->secret, secret,
> +			(strlen(secret) >= 24) ? 24 : strlen(secret));
> +
> +	pmd->cfg.log2_ring_size = ETH_MEMIF_DEFAULT_RING_SIZE;
> +	if (log2_ring_size != 0)
> +		pmd->cfg.log2_ring_size = log2_ring_size;
> +	pmd->cfg.num_s2m_rings = ETH_MEMIF_DEFAULT_NRXQ;
> +	pmd->cfg.num_m2s_rings = ETH_MEMIF_DEFAULT_NTXQ;
> +
> +	if (nrxq != 0) {
> +		if (role == MEMIF_ROLE_SLAVE)
> +			pmd->cfg.num_m2s_rings = nrxq;
> +		else
> +			pmd->cfg.num_s2m_rings = nrxq;
> +	}
> +	if (ntxq != 0) {
> +		if (role == MEMIF_ROLE_SLAVE)
> +			pmd->cfg.num_s2m_rings = ntxq;
> +		else
> +			pmd->cfg.num_m2s_rings = ntxq;
> +	}
> +
> +	pmd->cfg.buffer_size = ETH_MEMIF_DEFAULT_BUFFER_SIZE;
> +	if (buffer_size != 0)
> +		pmd->cfg.buffer_size = buffer_size;
> +
> +	/* FIXME: generate mac? */
> +	if (eth_addr == NULL)
> +		eth_addr = ETH_MEMIF_DEFAULT_ETH_ADDR;
> +
> +	sscanf(eth_addr, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
> +	       &pmd->eth_addr.addr_bytes[0], &pmd->eth_addr.addr_bytes[1],
> +	       &pmd->eth_addr.addr_bytes[2], &pmd->eth_addr.addr_bytes[3],
> +	       &pmd->eth_addr.addr_bytes[4], &pmd->eth_addr.addr_bytes[5]);
> +
> +	data = eth_dev->data;
> +	data->dev_private = pmd;
> +	data->numa_node = numa_node;
> +	data->mac_addrs = &pmd->eth_addr;
> +
> +	eth_dev->dev_ops = &ops;
> +	eth_dev->device = &vdev->device;
> +	eth_dev->rx_pkt_burst = eth_memif_rx;
> +	eth_dev->tx_pkt_burst = eth_memif_tx;
> +
> +	rte_eth_dev_probing_finish(eth_dev);
> +
> +	return ret;
> +}
> +
> +static int
> +memif_set_role(const char *key __rte_unused, const char *value,
> +	       void *extra_args)
> +{
> +	enum memif_role_t *role = (enum memif_role_t *)extra_args;
> +	if (strstr(value, "master") != NULL) {
> +		*role = MEMIF_ROLE_MASTER;
> +	} else if (strstr(value, "slave") != NULL) {
> +		*role = MEMIF_ROLE_SLAVE;

Single line blocks
> +	} else {
> +		MIF_LOG(ERR, "Unknown role: %s.", value);
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int
> +memif_set_zc(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	uint32_t *flags = (uint32_t *) extra_args;
> +
> +	if (strstr(value, "yes") != NULL) {
> +		*flags |= ETH_MEMIF_FLAG_ZERO_COPY;
> +	} else if (strstr(value, "no") != NULL) {
> +		*flags &= ~ETH_MEMIF_FLAG_ZERO_COPY;

Single line blocks.
> +	} else {
> +		MIF_LOG(ERR, "Failed to parse zero-copy param: %s.", value);
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int
> +memif_set_id(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	memif_interface_id_t *id = (memif_interface_id_t *) extra_args;
> +	/* even if parsing fails, 0 is a valid id */
> +	*id = strtoul(value, NULL, 10);
> +	return 0;
> +}
> +
> +static int
> +memif_set_bs(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	unsigned long int tmp;
> +	uint16_t *buffer_size = (uint16_t *) extra_args;
> +
> +	tmp = strtoul(value, NULL, 10);
> +	if ((tmp == 0) || (tmp > 0xFFFF)) {
> +		MIF_LOG(ERR, "Invalid buffer size: %s.", value);
> +		return -EINVAL;
> +	}
> +	*buffer_size = tmp;
> +	return 0;
> +}
> +
> +static int
> +memif_set_rs(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	unsigned long int tmp;
> +	memif_log2_ring_size_t *log2_ring_size =
> +	    (memif_log2_ring_size_t *) extra_args;
> +
> +	tmp = strtoul(value, NULL, 10);
> +	if ((tmp == 0) || (tmp > ETH_MEMIF_MAX_LOG2_RING_SIZE)) {
> +		MIF_LOG(ERR, "Invalid ring size: %s (max %u).",
> +			value, ETH_MEMIF_MAX_LOG2_RING_SIZE);
> +		return -EINVAL;
> +	}
> +	*log2_ring_size = tmp;
> +	return 0;
> +}
> +
> +static int
> +memif_set_nq(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	unsigned long int tmp;
> +	uint16_t *nq = (uint16_t *) extra_args;
> +
> +	tmp = strtoul(value, NULL, 10);
> +	if ((tmp == 0) || (tmp > 0xFF)) {
> +		MIF_LOG(ERR, "Invalid number of queues: %s.", value);
> +		return -EINVAL;
> +	}
> +	*nq = tmp;
> +	return 0;
> +}
> +
> +/* check if directory exists and if we have permission to read/write */
> +static inline int memif_check_socket_filename(const char *filename)
> +{
> +	char *dir = NULL, *tmp;
> +	uint32_t idx;
> +	int ret = 0;
> +
> +	tmp = strrchr(filename, '/');
> +	if (tmp != NULL) {
> +		idx = tmp - filename;
> +		dir = rte_zmalloc("memif_tmp", sizeof(char) * (idx + 2), 0);
> +		if (dir == NULL) {
> +			MIF_LOG(ERR, "Failed to allocate memory.");
> +			return -1;
> +		}
> +		strncpy(dir, filename, idx);
> +	}
> +
> +	if ((dir == NULL) || (faccessat(-1, dir, F_OK | R_OK |
> +					W_OK, AT_EACCESS) < 0)) {
> +		MIF_LOG(ERR, "Invalid directory: %s.", dir);
> +		ret = -EINVAL;
> +	}
> +
> +	if (dir != NULL)
> +		rte_free(dir);
> +
> +	return ret;
> +}
> +
> +static int rte_pmd_memif_probe(struct rte_vdev_device *vdev)
> +{
> +	int ret = 0;
> +	unsigned int i;
> +	struct rte_kvargs *kvlist;
> +	const struct rte_kvargs_pair *pair;
> +
> +	const char *name = rte_vdev_device_name(vdev);
> +
> +	enum memif_role_t role;
> +	memif_interface_id_t id;
> +
> +	uint16_t buffer_size;
> +	memif_log2_ring_size_t log2_ring_size;
> +	uint8_t nrxq, ntxq;
> +	const char *socket_filename;
> +	const char *eth_addr;
> +	uint32_t flags;
> +	const char *secret;
> +
> +	MIF_LOG(INFO, "Initialize MEMIF: %s.", name);
> +
> +	kvlist = rte_kvargs_parse(rte_vdev_device_args(vdev), valid_arguments);
> +
> +	/* set default values */
> +	role = MEMIF_ROLE_SLAVE;
> +	flags = 0;
> +	id = 0;
> +	buffer_size = 2048;
> +	log2_ring_size = 10;
> +	nrxq = 1;
> +	ntxq = 1;
> +	socket_filename = ETH_MEMIF_DEFAULT_SOCKET_FILENAME;
> +	secret = NULL;
> +	eth_addr = NULL;
> +
> +	/* parse parameters */
> +	if (kvlist != NULL) {
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_ROLE_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_ROLE_ARG,
> +						 &memif_set_role, &role);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_ID_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_ID_ARG,
> +						 &memif_set_id, &id);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_BUFFER_SIZE_ARG) == 1) {
> +			ret =
> +			    rte_kvargs_process(kvlist,
> +					       ETH_MEMIF_BUFFER_SIZE_ARG,
> +					       &memif_set_bs, &buffer_size);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_RING_SIZE_ARG) == 1) {
> +			ret =
> +			    rte_kvargs_process(kvlist, ETH_MEMIF_RING_SIZE_ARG,
> +					       &memif_set_rs, &log2_ring_size);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_NRXQ_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_NRXQ_ARG,
> +						 &memif_set_nq, &nrxq);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_NTXQ_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_NTXQ_ARG,
> +						 &memif_set_nq, &ntxq);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_SOCKET_ARG) == 1) {
> +			for (i = 0; i < kvlist->count; i++) {
> +				pair = &kvlist->pairs[i];
> +				if (strcmp(pair->key, ETH_MEMIF_SOCKET_ARG) ==
> +				    0) {
> +					socket_filename = pair->value;
> +					ret =
> +					    memif_check_socket_filename
> +					    (socket_filename);
> +					if (ret < 0)
> +						goto exit;
> +				}
> +			}
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_MAC_ARG) == 1) {
> +			for (i = 0; i < kvlist->count; i++) {
> +				pair = &kvlist->pairs[i];
> +				if (strcmp(pair->key, ETH_MEMIF_MAC_ARG) == 0) {
> +					eth_addr = pair->value;
> +				}
> +			}
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_ZC_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_ZC_ARG,
> +						 &memif_set_zc, &flags);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_SECRET_ARG) == 1) {
> +			for (i = 0; i < kvlist->count; i++) {
> +				pair = &kvlist->pairs[i];
> +				if (strcmp(pair->key, ETH_MEMIF_SECRET_ARG) ==
> +				    0) {
> +					secret = pair->value;
> +				}

Single line blocks in this function.
> +			}
> +		}
> +	}
> +
> +	/* create interface */
> +	ret =
> +	    memif_create(vdev, role, id, flags, socket_filename, log2_ring_size,
> +			 nrxq, ntxq, buffer_size, secret, eth_addr);
> +
> + exit:
> +	if (kvlist != NULL)
> +		rte_kvargs_free(kvlist);
> +	return ret;
> +}
> +
> +static int rte_pmd_memif_remove(struct rte_vdev_device *vdev)
> +{
> +	struct rte_eth_dev *eth_dev;
> +
> +	eth_dev = rte_eth_dev_allocated(rte_vdev_device_name(vdev));
> +	if (eth_dev == NULL)
> +		return 0;
> +
> +	struct pmd_internals *pmd = eth_dev->data->dev_private;
> +
> +	memif_msg_enq_disconnect(pmd->cc, "Invalid message size", 0);
> +	memif_disconnect(eth_dev);
> +
> +	memif_socket_remove_device(pmd);
> +
> +	pmd->vdev = NULL;
> +
> +	rte_free(eth_dev->data->dev_private);
> +
> +	rte_eth_dev_release_port(eth_dev);
> +
> +	return 0;
> +}
> +
> +static struct rte_vdev_driver pmd_memif_drv = {
> +	.probe = rte_pmd_memif_probe,
> +	.remove = rte_pmd_memif_remove,
> +};
> +
> +RTE_PMD_REGISTER_VDEV(net_memif, pmd_memif_drv);
> +RTE_PMD_REGISTER_ALIAS(net_memif, eth_memif);
> +RTE_PMD_REGISTER_PARAM_STRING(net_memif,
> +			      ETH_MEMIF_ID_ARG "=<int>"
> +			      ETH_MEMIF_ROLE_ARG "=<string>"
> +			      ETH_MEMIF_BUFFER_SIZE_ARG "=<int>"
> +			      ETH_MEMIF_RING_SIZE_ARG "=<int>"
> +			      ETH_MEMIF_NRXQ_ARG "=<int>"
> +			      ETH_MEMIF_NTXQ_ARG "=<int>"
> +			      ETH_MEMIF_SOCKET_ARG "=<string>"
> +			      ETH_MEMIF_MAC_ARG "=xx:xx:xx:xx:xx:xx"
> +			      ETH_MEMIF_ZC_ARG "=<string>"
> +			      ETH_MEMIF_SECRET_ARG "=<string>");
> +
> +RTE_INIT(memif_init_log)
> +{
> +	memif_logtype = rte_log_register("pmd.net.memif");
> +	if (memif_logtype >= 0)
> +		rte_log_set_level(memif_logtype, RTE_LOG_NOTICE);
> +}
> diff --git a/drivers/net/memif/rte_eth_memif.h b/drivers/net/memif/rte_eth_memif.h
> new file mode 100644
> index 000000000..bbd79e1a5
> --- /dev/null
> +++ b/drivers/net/memif/rte_eth_memif.h
> @@ -0,0 +1,189 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#ifndef _RTE_ETH_MEMIF_H_
> +#define _RTE_ETH_MEMIF_H_
> +
> +#ifndef _GNU_SOURCE
> +#define _GNU_SOURCE
> +#endif				/* GNU_SOURCE */
> +
> +#include <stdio.h>
> +#include <sys/queue.h>
> +
> +#include <rte_ethdev_driver.h>
> +#include <rte_ether.h>
> +#include <rte_timer.h>
> +#include <rte_interrupts.h>
> +
> +#include <memif.h>
> +
> +/* generate mac? */
> +#define ETH_MEMIF_DEFAULT_ETH_ADDR		"01:ab:23:cd:45:ef"
> +
> +#define ETH_MEMIF_DEFAULT_SOCKET_FILENAME	"/tmp/memif.sock"
> +#define ETH_MEMIF_DEFAULT_RING_SIZE		10
> +#define ETH_MEMIF_DEFAULT_NRXQ			1
> +#define ETH_MEMIF_DEFAULT_NTXQ			1
> +#define ETH_MEMIF_DEFAULT_BUFFER_SIZE		2048
> +
> +#define ETH_MEMIF_MAX_NUM_Q_PAIRS		256
> +#define ETH_MEMIF_MAX_LOG2_RING_SIZE		14
> +#define ETH_MEMIF_MAX_REGION_IDX		255
> +
> +int memif_logtype;
> +
> +#define memif_min(a,b) (((a) < (b)) ? (a) : (b))
> +
> +#define MIF_LOG(level, fmt, args...) \
> +do {							\
> +	rte_log(RTE_LOG_ ## level, memif_logtype,	\
> +		"%s(): " fmt "\n", __func__, ##args);	\
> +} while (0)
> +
> +enum memif_role_t {
> +	MEMIF_ROLE_MASTER = 0,
> +	MEMIF_ROLE_SLAVE = 1,
> +};
> +
> +/* Shared memory region. */
> +struct memif_region {
> +	void *addr;
> +	memif_region_size_t region_size;
> +	int fd;
> +	uint32_t buffer_offset;
> +};
> +
> +struct memif_queue {
> +	struct rte_mempool *mempool;
> +	uint16_t in_port;
> +
> +	struct pmd_internals *pmd;
> +
> +	struct rte_intr_handle intr_handle;
> +
> +	/* ring info */
> +	memif_ring_type_t type;
> +	memif_ring_t *ring;
> +	memif_log2_ring_size_t log2_ring_size;
> +
> +	memif_region_index_t region;
> +	memif_region_offset_t offset;
> +
> +	uint16_t last_head;
> +	uint16_t last_tail;
> +	uint32_t *buffers;
> +
> +	/* rx/tx info */
> +	uint64_t n_pkts;
> +	uint64_t n_bytes;
> +	uint64_t n_err;
> +};
> +
> +struct pmd_internals {
> +	int if_index;
> +	memif_interface_id_t id;
> +	enum memif_role_t role;
> +	uint32_t flags;
> +#define ETH_MEMIF_FLAG_CONNECTING	(1 << 0)
> +#define ETH_MEMIF_FLAG_CONNECTED	(1 << 1)
> +#define ETH_MEMIF_FLAG_ZERO_COPY	(1 << 2)
> +/* device has not been configured and can not accept connection requests */
> +#define ETH_MEMIF_FLAG_DISABLED		(1 << 3)
> +
> +	struct ether_addr eth_addr;
> +	char *socket_filename;
> +	char secret[24];
> +
> +	struct memif_control_channel *cc;
> +
> +	struct memif_region *regions;
> +	uint8_t regions_num;
> +
> +	struct memif_queue *rx_queues;
> +	struct memif_queue *tx_queues;
> +
> +	/* remote info */
> +	char remote_name[64];
> +	char remote_if_name[64];
> +
> +	/* Configured parameters (max values) */
> +	struct {
> +		memif_log2_ring_size_t log2_ring_size;
> +		uint8_t num_s2m_rings;
> +		uint8_t num_m2s_rings;
> +		uint16_t buffer_size;
> +	} cfg;
> +
> +	/* Parameters used in active connection */
> +	struct {
> +		memif_log2_ring_size_t log2_ring_size;
> +		uint8_t num_s2m_rings;
> +		uint8_t num_m2s_rings;
> +		uint16_t buffer_size;
> +	} run;
> +
> +	char local_disc_string[96];
> +	char remote_disc_string[96];
> +
> +	/* vdev handle */
> +	struct rte_vdev_device *vdev;
> +};
> +
> +void memif_free_regions(struct pmd_internals *pmd);
> +
> +/*
> + * Finalize connection establishment process. Map shared memory file
> + * (master role), initialize ring queue, set link status up.
> + */
> +int memif_connect(struct pmd_internals *pmd);
> +
> +/*
> + * Create shared memory file and initialize ring queue.
> + * Only called by slave when establishing connection
> + */
> +int memif_init_regions_and_queues(struct pmd_internals *pmd);
> +
> +const char *memif_version(void);
> +
> +#ifndef MFD_HUGETLB
> +#ifndef __NR_memfd_create
> +
> +#if defined __x86_64__
> +#define __NR_memfd_create 319
> +#elif defined __arm__
> +#define __NR_memfd_create 385
> +#elif defined __aarch64__
> +#define __NR_memfd_create 279
> +#else
> +#error "__NR_memfd_create unknown for this architecture"
> +#endif
> +
> +#endif				/* __NR_memfd_create */
> +
> +static inline int memfd_create(const char *name, unsigned int flags)
> +{
> +	return syscall(__NR_memfd_create, name, flags);
> +}
> +#endif				/* MFD_HUGETLB */
> +
> +#ifndef F_LINUX_SPECIFIC_BASE
> +#define F_LINUX_SPECIFIC_BASE 1024
> +#endif
> +
> +#ifndef MFD_ALLOW_SEALING
> +#define MFD_ALLOW_SEALING       0x0002U
> +#endif
> +
> +#ifndef F_ADD_SEALS
> +#define F_ADD_SEALS (F_LINUX_SPECIFIC_BASE + 9)
> +#define F_GET_SEALS (F_LINUX_SPECIFIC_BASE + 10)
> +
> +#define F_SEAL_SEAL     0x0001	/* prevent further seals from being set */
> +#define F_SEAL_SHRINK   0x0002	/* prevent file from shrinking */
> +#define F_SEAL_GROW     0x0004	/* prevent file from growing */
> +#define F_SEAL_WRITE    0x0008	/* prevent writes */
> +#endif
> +
> +#endif				/* RTE_ETH_MEMIF_H */
> diff --git a/drivers/net/memif/rte_pmd_memif_version.map b/drivers/net/memif/rte_pmd_memif_version.map
> new file mode 100644
> index 000000000..aee560afa
> --- /dev/null
> +++ b/drivers/net/memif/rte_pmd_memif_version.map
> @@ -0,0 +1,4 @@
> +DPDK_2.0 {
> +
> +        local: *;
> +};

Should be DPDK_19.02 for the release number

> diff --git a/drivers/net/meson.build b/drivers/net/meson.build
> index 980eec233..b0becbf31 100644
> --- a/drivers/net/meson.build
> +++ b/drivers/net/meson.build
> @@ -21,6 +21,7 @@ drivers = ['af_packet',
> 	'ixgbe',
> 	'kni',
> 	'liquidio',
> +	'memif',
> 	'mlx4',
> 	'mlx5',
> 	'mvneta',
> diff --git a/mk/rte.app.mk b/mk/rte.app.mk
> index 5699d979d..f236c5ebc 100644
> --- a/mk/rte.app.mk
> +++ b/mk/rte.app.mk
> @@ -168,6 +168,7 @@ ifeq ($(CONFIG_RTE_LIBRTE_KNI),y)
> _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_KNI)        += -lrte_pmd_kni
> endif
> _LDLIBS-$(CONFIG_RTE_LIBRTE_LIO_PMD)        += -lrte_pmd_lio
> +_LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF)      += -lrte_pmd_memif
> ifeq ($(CONFIG_RTE_LIBRTE_MLX4_DLOPEN_DEPS),y)
> _LDLIBS-$(CONFIG_RTE_LIBRTE_MLX4_PMD)       += -lrte_pmd_mlx4 -ldl
> else
> -- 
> 2.17.1
> 

Regards,
Keith
  
Wiles, Keith Dec. 10, 2018, 3:13 p.m. UTC | #4
> On Dec 10, 2018, at 8:48 AM, Wiles, Keith <keith.wiles@intel.com> wrote:
> 
> 
> 
>> On Dec 10, 2018, at 4:06 AM, Jakub Grajciar <jgrajcia@cisco.com> wrote:
> 
> I do not like being the coding style police, but that is most of the comments here and I will try to test this one later this week. Plus I am sure I missed some style problems, if you have not read the coding style for DPDK please have a read.
> 
> http://doc.dpdk.org/guides/contributing/coding_style.html
> 
> One comment, why did you include all of the code to handle memif instead of including the libmemif.a from VPP. I worry if libmemif is changed then we have a breakage. I do not mind the PMD being standalone and I do like not having the dependence.
> 
> As I did not dive into the code much it does look reasonable and I hope to give it a try later this week.
>> 

A couple more items, do you plan on writing the documentation for the PMD and provide an example program?

Regards,
Keith
  
Stephen Hemminger Dec. 10, 2018, 4:20 p.m. UTC | #5
Things I saw so far, probably not everything

> +
> +_Static_assert(sizeof(memif_msg_t) == 128, "Size of memif_msg_t must be 128");
> +

DPDK uses RTE_BUILD_BUG_ON for checks like this.

> diff --git a/drivers/net/memif/Makefile b/drivers/net/memif/Makefile
> new file mode 100644
> index 000000000..a82448423
> --- /dev/null
> +++ b/drivers/net/memif/Makefile
> @@ -0,0 +1,29 @@
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> +
> +include $(RTE_SDK)/mk/rte.vars.mk
> +
> +#
> +# library name
> +#
> +LIB = librte_pmd_memif.a
> +
> +EXPORT_MAP := rte_pmd_memif_version.map
> +
> +LIBABIVER := 1
> +
> +CFLAGS += -O3
> +CFLAGS += -I$(SRCDIR)
> +CFLAGS += $(WERROR_FLAGS)
> +CFLAGS += -Wno-pointer-arith
> +LDLIBS += -lrte_eal -lrte_mbuf -lrte_mempool -lrte_ring
> +LDLIBS += -lrte_ethdev -lrte_net -lrte_kvargs
> +LDLIBS += -lrte_bus_vdev
> +
> +#
> +# all source are stored in SRCS-y
> +#
> +SRCS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += rte_eth_memif.c
> +SR

What about meson build?

...

> +
> +/*
> + * fd.io coding-style-patch-verification: ON
> + *
> + * Local Variables:
> + * eval: (c-set-style "gnu")
> + * End:
> + */


This is DPDK not FD.io, this must be removed.


> +static inline ssize_t memif_msg_send(int fd, memif_msg_t * msg, int afd)
> +{

inline is not necessary with current generation compilers.
Only needed in header file.

> +
> +#define memif_min(a,b) (((a) < (b)) ? (a) : (b))

Use RTE_MIN() instead.

Also, what about documentation??
  
Ananyev, Konstantin Dec. 11, 2018, 7:39 a.m. UTC | #6
Hi,

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Jakub Grajciar
> Sent: Monday, December 10, 2018 10:07 AM
> To: dev@dpdk.org
> Cc: Jakub Grajciar <jgrajcia@cisco.com>
> Subject: [dpdk-dev] [RFC v2] /net: memory interface (memif)

Could you please add some explanation -
what for this driver is intended to be used (which pseudo-device, etc.).
Konstantin

> 
> Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
> ---
>  config/common_base                          |    5 +
>  config/common_linuxapp                      |    1 +
>  drivers/net/Makefile                        |    1 +
>  drivers/net/memif/Makefile                  |   29 +
>  drivers/net/memif/memif.h                   |  156 +++
>  drivers/net/memif/memif_socket.c            | 1085 +++++++++++++++++
>  drivers/net/memif/memif_socket.h            |   57 +
>  drivers/net/memif/meson.build               |    8 +
>  drivers/net/memif/rte_eth_memif.c           | 1172 +++++++++++++++++++
>  drivers/net/memif/rte_eth_memif.h           |  189 +++
>  drivers/net/memif/rte_pmd_memif_version.map |    4 +
>  drivers/net/meson.build                     |    1 +
>  mk/rte.app.mk                               |    1 +
>  13 files changed, 2709 insertions(+)
>  create mode 100644 drivers/net/memif/Makefile
>  create mode 100644 drivers/net/memif/memif.h
>  create mode 100644 drivers/net/memif/memif_socket.c
>  create mode 100644 drivers/net/memif/memif_socket.h
>  create mode 100644 drivers/net/memif/meson.build
>  create mode 100644 drivers/net/memif/rte_eth_memif.c
>  create mode 100644 drivers/net/memif/rte_eth_memif.h
>  create mode 100644 drivers/net/memif/rte_pmd_memif_version.map
> 
> diff --git a/config/common_base b/config/common_base
> index d12ae98bc..b8ed10ae5 100644
> --- a/config/common_base
> +++ b/config/common_base
> @@ -403,6 +403,11 @@ CONFIG_RTE_LIBRTE_VMXNET3_DEBUG_TX_FREE=n
>  #
>  CONFIG_RTE_LIBRTE_PMD_AF_PACKET=n
> 
> +#
> +# Compile Memory Interface PMD driver (Linux only)
> +#
> +CONFIG_RTE_LIBRTE_PMD_MEMIF=n
> +
>  #
>  # Compile link bonding PMD library
>  #
> diff --git a/config/common_linuxapp b/config/common_linuxapp
> index 6c1c8d0f4..42cbde8f5 100644
> --- a/config/common_linuxapp
> +++ b/config/common_linuxapp
> @@ -18,6 +18,7 @@ CONFIG_RTE_LIBRTE_VHOST_POSTCOPY=n
>  CONFIG_RTE_LIBRTE_PMD_VHOST=y
>  CONFIG_RTE_LIBRTE_IFC_PMD=y
>  CONFIG_RTE_LIBRTE_PMD_AF_PACKET=y
> +CONFIG_RTE_LIBRTE_PMD_MEMIF=y
>  CONFIG_RTE_LIBRTE_PMD_SOFTNIC=y
>  CONFIG_RTE_LIBRTE_PMD_TAP=y
>  CONFIG_RTE_LIBRTE_AVP_PMD=y
> diff --git a/drivers/net/Makefile b/drivers/net/Makefile
> index c0386feb9..0feab5241 100644
> --- a/drivers/net/Makefile
> +++ b/drivers/net/Makefile
> @@ -32,6 +32,7 @@ DIRS-$(CONFIG_RTE_LIBRTE_FM10K_PMD) += fm10k
>  DIRS-$(CONFIG_RTE_LIBRTE_I40E_PMD) += i40e
>  DIRS-$(CONFIG_RTE_LIBRTE_IXGBE_PMD) += ixgbe
>  DIRS-$(CONFIG_RTE_LIBRTE_LIO_PMD) += liquidio
> +DIRS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += memif
>  DIRS-$(CONFIG_RTE_LIBRTE_MLX4_PMD) += mlx4
>  DIRS-$(CONFIG_RTE_LIBRTE_MLX5_PMD) += mlx5
>  DIRS-$(CONFIG_RTE_LIBRTE_MVNETA_PMD) += mvneta
> diff --git a/drivers/net/memif/Makefile b/drivers/net/memif/Makefile
> new file mode 100644
> index 000000000..a82448423
> --- /dev/null
> +++ b/drivers/net/memif/Makefile
> @@ -0,0 +1,29 @@
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> +
> +include $(RTE_SDK)/mk/rte.vars.mk
> +
> +#
> +# library name
> +#
> +LIB = librte_pmd_memif.a
> +
> +EXPORT_MAP := rte_pmd_memif_version.map
> +
> +LIBABIVER := 1
> +
> +CFLAGS += -O3
> +CFLAGS += -I$(SRCDIR)
> +CFLAGS += $(WERROR_FLAGS)
> +CFLAGS += -Wno-pointer-arith
> +LDLIBS += -lrte_eal -lrte_mbuf -lrte_mempool -lrte_ring
> +LDLIBS += -lrte_ethdev -lrte_net -lrte_kvargs
> +LDLIBS += -lrte_bus_vdev
> +
> +#
> +# all source are stored in SRCS-y
> +#
> +SRCS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += rte_eth_memif.c
> +SRCS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += memif_socket.c
> +
> +include $(RTE_SDK)/mk/rte.lib.mk
> diff --git a/drivers/net/memif/memif.h b/drivers/net/memif/memif.h
> new file mode 100644
> index 000000000..6a23dbad7
> --- /dev/null
> +++ b/drivers/net/memif/memif.h
> @@ -0,0 +1,156 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#ifndef _MEMIF_H_
> +#define _MEMIF_H_
> +
> +#ifndef MEMIF_CACHELINE_SIZE
> +#define MEMIF_CACHELINE_SIZE 64
> +#endif
> +
> +#define MEMIF_COOKIE		0x3E31F20
> +#define MEMIF_VERSION_MAJOR	2
> +#define MEMIF_VERSION_MINOR	0
> +#define MEMIF_VERSION		((MEMIF_VERSION_MAJOR << 8) | MEMIF_VERSION_MINOR)
> +
> +/*
> + *  Type definitions
> + */
> +
> +typedef enum memif_msg_type {
> +	MEMIF_MSG_TYPE_NONE = 0,
> +	MEMIF_MSG_TYPE_ACK = 1,
> +	MEMIF_MSG_TYPE_HELLO = 2,
> +	MEMIF_MSG_TYPE_INIT = 3,
> +	MEMIF_MSG_TYPE_ADD_REGION = 4,
> +	MEMIF_MSG_TYPE_ADD_RING = 5,
> +	MEMIF_MSG_TYPE_CONNECT = 6,
> +	MEMIF_MSG_TYPE_CONNECTED = 7,
> +	MEMIF_MSG_TYPE_DISCONNECT = 8,
> +} memif_msg_type_t;
> +
> +typedef enum {
> +	MEMIF_RING_S2M = 0,
> +	MEMIF_RING_M2S = 1
> +} memif_ring_type_t;
> +
> +typedef enum {
> +	MEMIF_INTERFACE_MODE_ETHERNET = 0,
> +	MEMIF_INTERFACE_MODE_IP = 1,
> +	MEMIF_INTERFACE_MODE_PUNT_INJECT = 2,
> +} memif_interface_mode_t;
> +
> +typedef uint16_t memif_region_index_t;
> +typedef uint32_t memif_region_offset_t;
> +typedef uint64_t memif_region_size_t;
> +typedef uint16_t memif_ring_index_t;
> +typedef uint32_t memif_interface_id_t;
> +typedef uint16_t memif_version_t;
> +typedef uint8_t memif_log2_ring_size_t;
> +
> +/*
> + *  Socket messages
> + */
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint8_t name[32];
> +	memif_version_t min_version;
> +	memif_version_t max_version;
> +	memif_region_index_t max_region;
> +	memif_ring_index_t max_m2s_ring;
> +	memif_ring_index_t max_s2m_ring;
> +	memif_log2_ring_size_t max_log2_ring_size;
> +} memif_msg_hello_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	memif_version_t version;
> +	memif_interface_id_t id;
> +	memif_interface_mode_t mode:8;
> +	uint8_t secret[24];
> +	uint8_t name[32];
> +} memif_msg_init_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	memif_region_index_t index;
> +	memif_region_size_t size;
> +} memif_msg_add_region_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint16_t flags;
> +#define MEMIF_MSG_ADD_RING_FLAG_S2M	(1 << 0)
> +	memif_ring_index_t index;
> +	memif_region_index_t region;
> +	memif_region_offset_t offset;
> +	memif_log2_ring_size_t log2_ring_size;
> +	uint16_t private_hdr_size;	/* used for private metadata */
> +} memif_msg_add_ring_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint8_t if_name[32];
> +} memif_msg_connect_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint8_t if_name[32];
> +} memif_msg_connected_t;
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint32_t code;
> +	uint8_t string[96];
> +} memif_msg_disconnect_t;
> +
> +typedef struct __attribute__ ((packed, aligned(128))) {
> +	memif_msg_type_t type:16;
> +	union {
> +		memif_msg_hello_t hello;
> +		memif_msg_init_t init;
> +		memif_msg_add_region_t add_region;
> +		memif_msg_add_ring_t add_ring;
> +		memif_msg_connect_t connect;
> +		memif_msg_connected_t connected;
> +		memif_msg_disconnect_t disconnect;
> +	};
> +} memif_msg_t;
> +
> +_Static_assert(sizeof(memif_msg_t) == 128, "Size of memif_msg_t must be 128");
> +
> +/*
> + *  Ring and Descriptor Layout
> + */
> +
> +typedef struct __attribute__ ((packed)) {
> +	uint16_t flags;
> +#define MEMIF_DESC_FLAG_NEXT (1 << 0)
> +	memif_region_index_t region;
> +	uint32_t length;
> +	memif_region_offset_t offset;
> +	uint32_t metadata;
> +} memif_desc_t;
> +
> +_Static_assert(sizeof(memif_desc_t) == 16,
> +	       "Size of memif_dsct_t must be 16 bytes");
> +
> +#define MEMIF_CACHELINE_ALIGN_MARK(mark) \
> +  uint8_t mark[0] __attribute__((aligned(MEMIF_CACHELINE_SIZE)))
> +
> +typedef struct {
> +	MEMIF_CACHELINE_ALIGN_MARK(cacheline0);
> +	uint32_t cookie;
> +	uint16_t flags;
> +#define MEMIF_RING_FLAG_MASK_INT 1
> +	volatile uint16_t head;
> +	 MEMIF_CACHELINE_ALIGN_MARK(cacheline1);
> +	volatile uint16_t tail;
> +	 MEMIF_CACHELINE_ALIGN_MARK(cacheline2);
> +	memif_desc_t desc[0];
> +} memif_ring_t;
> +
> +#endif				/* _MEMIF_H_ */
> +
> +/*
> + * fd.io coding-style-patch-verification: ON
> + *
> + * Local Variables:
> + * eval: (c-set-style "gnu")
> + * End:
> + */
> diff --git a/drivers/net/memif/memif_socket.c b/drivers/net/memif/memif_socket.c
> new file mode 100644
> index 000000000..afd4ac888
> --- /dev/null
> +++ b/drivers/net/memif/memif_socket.c
> @@ -0,0 +1,1085 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#include <stdlib.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <sys/types.h>
> +#include <sys/socket.h>
> +#include <sys/un.h>
> +#include <sys/ioctl.h>
> +#include <errno.h>
> +
> +#include <rte_version.h>
> +#include <rte_mbuf.h>
> +#include <rte_ether.h>
> +#include <rte_ethdev_driver.h>
> +#include <rte_ethdev_vdev.h>
> +#include <rte_malloc.h>
> +#include <rte_kvargs.h>
> +#include <rte_bus_vdev.h>
> +#include <rte_hash.h>
> +#include <rte_jhash.h>
> +
> +#include <rte_eth_memif.h>
> +#include <memif_socket.h>
> +
> +static void memif_intr_handler(void *arg);
> +
> +static inline ssize_t memif_msg_send(int fd, memif_msg_t * msg, int afd)
> +{
> +	struct msghdr mh = { 0 };
> +	struct iovec iov[1];
> +	char ctl[CMSG_SPACE(sizeof(int))];
> +
> +	iov[0].iov_base = (void *)msg;
> +	iov[0].iov_len = sizeof(memif_msg_t);
> +	mh.msg_iov = iov;
> +	mh.msg_iovlen = 1;
> +
> +	if (afd > 0) {
> +		struct cmsghdr *cmsg;
> +		memset(&ctl, 0, sizeof(ctl));
> +		mh.msg_control = ctl;
> +		mh.msg_controllen = sizeof(ctl);
> +		cmsg = CMSG_FIRSTHDR(&mh);
> +		cmsg->cmsg_len = CMSG_LEN(sizeof(int));
> +		cmsg->cmsg_level = SOL_SOCKET;
> +		cmsg->cmsg_type = SCM_RIGHTS;
> +		rte_memcpy(CMSG_DATA(cmsg), &afd, sizeof(int));
> +	}
> +
> +	return sendmsg(fd, &mh, 0);
> +}
> +
> +static inline int memif_msg_send_from_queue(struct memif_control_channel *cc)
> +{
> +	ssize_t size;
> +	int ret = 0;
> +	struct memif_msg_queue_elt *e;
> +	e = TAILQ_FIRST(&cc->msg_queue);
> +	if (e == NULL)
> +		return 0;
> +
> +	size = memif_msg_send(cc->intr_handle.fd, &e->msg, e->fd);
> +	if (size != sizeof(memif_msg_t)) {
> +		MIF_LOG(ERR, "sendmsg fail: %s.", strerror(errno));
> +		ret = -1;
> +	} else {
> +		MIF_LOG(DEBUG, "%s: Sent msg type %u.",
> +			(cc->pmd !=
> +			 NULL) ? rte_vdev_device_name(cc->pmd->
> +						      vdev) : "memif_driver",
> +			e->msg.type);
> +	}
> +	TAILQ_REMOVE(&cc->msg_queue, e, next);
> +	rte_free(e);
> +
> +	return ret;
> +}
> +
> +static inline struct memif_msg_queue_elt *memif_msg_enq(struct
> +							memif_control_channel
> +							*cc)
> +{
> +	struct memif_msg_queue_elt *e = rte_zmalloc("memif_msg",
> +						    sizeof(struct
> +							   memif_msg_queue_elt),
> +						    0);
> +	if (e == NULL) {
> +		MIF_LOG(ERR, "Failed to allocate control message.");
> +		return NULL;
> +	}
> +
> +	e->fd = -1;
> +	TAILQ_INSERT_TAIL(&cc->msg_queue, e, next);
> +
> +	return e;
> +}
> +
> +void
> +memif_msg_enq_disconnect(struct memif_control_channel *cc, const char *reason,
> +			 int err_code)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(cc);
> +	if (e == NULL) {
> +		MIF_LOG(WARNING, "%s: Failed to enqueue disconnect message.",
> +			(cc->pmd !=
> +			 NULL) ? rte_vdev_device_name(cc->pmd->
> +						      vdev) : "memif_driver");
> +		return;
> +	}
> +
> +	memif_msg_disconnect_t *d = &e->msg.disconnect;
> +
> +	e->msg.type = MEMIF_MSG_TYPE_DISCONNECT;
> +	d->code = err_code;
> +
> +	if (reason != NULL) {
> +		strncpy((char *)d->string, reason, strlen(reason));
> +		if (cc->pmd != NULL) {
> +			strncpy(cc->pmd->local_disc_string, reason,
> +				strlen(reason));
> +		}
> +	}
> +}
> +
> +static int memif_msg_enq_hello(struct memif_control_channel *cc)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(cc);
> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_hello_t *h = &e->msg.hello;
> +
> +	e->msg.type = MEMIF_MSG_TYPE_HELLO;
> +	h->min_version = MEMIF_VERSION;
> +	h->max_version = MEMIF_VERSION;
> +	h->max_s2m_ring = ETH_MEMIF_MAX_NUM_Q_PAIRS;
> +	h->max_m2s_ring = ETH_MEMIF_MAX_NUM_Q_PAIRS;
> +	h->max_region = ETH_MEMIF_MAX_REGION_IDX;
> +	h->max_log2_ring_size = ETH_MEMIF_MAX_LOG2_RING_SIZE;
> +
> +	strncpy((char *)h->name, rte_version(), strlen(rte_version()));
> +
> +	return 0;
> +}
> +
> +static int memif_msg_receive_hello(struct pmd_internals *pmd, memif_msg_t * msg)
> +{
> +	memif_msg_hello_t *h = &msg->hello;
> +
> +	if (h->min_version > MEMIF_VERSION || h->max_version < MEMIF_VERSION) {
> +		memif_msg_enq_disconnect(pmd->cc, "Incompatible memif version",
> +					 0);
> +		return -1;
> +	}
> +
> +	/* Set parameters for active connection */
> +	pmd->run.num_s2m_rings = memif_min(h->max_s2m_ring + 1,
> +					   pmd->cfg.num_s2m_rings);
> +	pmd->run.num_m2s_rings = memif_min(h->max_m2s_ring + 1,
> +					   pmd->cfg.num_m2s_rings);
> +	pmd->run.log2_ring_size = memif_min(h->max_log2_ring_size,
> +					    pmd->cfg.log2_ring_size);
> +	pmd->run.buffer_size = pmd->cfg.buffer_size;
> +
> +	strncpy(pmd->remote_name, (char *)h->name, strlen((char *)h->name));
> +
> +	MIF_LOG(DEBUG, "%s: Connecting to %s.",
> +		rte_vdev_device_name(pmd->vdev), pmd->remote_name);
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_init(struct memif_control_channel *cc, memif_msg_t * msg)
> +{
> +	memif_msg_init_t *i = &msg->init;
> +	struct memif_socket_pmd_list_elt *elt;
> +	struct pmd_internals *pmd;
> +
> +	if (i->version != MEMIF_VERSION) {
> +		memif_msg_enq_disconnect(cc, "Incompatible memif version", 0);
> +		return -1;
> +	}
> +
> +	if (cc->socket == NULL) {
> +		memif_msg_enq_disconnect(cc, "Device error", 0);
> +		return -1;
> +	}
> +
> +	/* Find device with requested ID */
> +	TAILQ_FOREACH(elt, &cc->socket->pmd_queue, next) {
> +		pmd = elt->pmd;
> +		if (((pmd->flags & ETH_MEMIF_FLAG_DISABLED) == 0)
> +		    && (pmd->id == i->id)) {
> +			/* assign control channel to device */
> +			cc->pmd = pmd;
> +			pmd->cc = cc;
> +
> +			if (i->mode != MEMIF_INTERFACE_MODE_ETHERNET) {
> +				memif_msg_enq_disconnect(pmd->cc,
> +							 "Only ethernet mode supported",
> +							 0);
> +				return -1;
> +			}
> +
> +			if (pmd->flags && (ETH_MEMIF_FLAG_CONNECTING |
> +					   ETH_MEMIF_FLAG_CONNECTED)) {
> +				memif_msg_enq_disconnect(pmd->cc,
> +							 "Already connected",
> +							 0);
> +				return -1;
> +			}
> +			strncpy(pmd->remote_name, (char *)i->name,
> +				strlen((char *)i->name));
> +
> +			if (*pmd->secret != '\0') {
> +				if (*i->secret == '\0') {
> +					memif_msg_enq_disconnect(pmd->cc,
> +								 "Secret required",
> +								 0);
> +					return -1;
> +				}
> +				if (strcmp(pmd->secret, (char *)i->secret) != 0) {
> +					memif_msg_enq_disconnect(pmd->cc,
> +								 "Incorrect secret",
> +								 0);
> +					return -1;
> +				}
> +			}
> +
> +			pmd->flags |= ETH_MEMIF_FLAG_CONNECTING;
> +			return 0;
> +		}
> +	}
> +
> +	/* ID not found on this socket */
> +	MIF_LOG(DEBUG, "ID %u not found.", i->id);
> +	memif_msg_enq_disconnect(cc, "ID not found", 0);
> +	return -1;
> +}
> +
> +static int
> +memif_msg_receive_add_region(struct pmd_internals *pmd, memif_msg_t * msg,
> +			     int fd)
> +{
> +	memif_msg_add_region_t *ar = &msg->add_region;
> +
> +	if (fd < 0) {
> +		memif_msg_enq_disconnect(pmd->cc, "Missing region fd", 0);
> +		return -1;
> +	}
> +
> +	struct memif_region *mr;
> +
> +	if (ar->index > ETH_MEMIF_MAX_REGION_IDX) {
> +		memif_msg_enq_disconnect(pmd->cc, "Invalid region index", 0);
> +		return -1;
> +	}
> +
> +	mr = rte_realloc(pmd->regions, sizeof(struct memif_region) *
> +			 (ar->index + 1), 0);
> +	if (mr == NULL) {
> +		memif_msg_enq_disconnect(pmd->cc, "Device error", 0);
> +		return -1;
> +	}
> +
> +	pmd->regions = mr;
> +	pmd->regions[ar->index].fd = fd;
> +	pmd->regions[ar->index].region_size = ar->size;
> +	pmd->regions[ar->index].addr = NULL;
> +	pmd->regions_num++;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_add_ring(struct pmd_internals *pmd, memif_msg_t * msg, int fd)
> +{
> +	memif_msg_add_ring_t *ar = &msg->add_ring;
> +
> +	if (fd < 0) {
> +		memif_msg_enq_disconnect(pmd->cc, "Missing interrupt fd", 0);
> +		return -1;
> +	}
> +
> +	struct memif_queue *mq;
> +
> +	/* check if we have enough queues */
> +	if (ar->flags & MEMIF_MSG_ADD_RING_FLAG_S2M) {
> +		if (ar->index >= pmd->cfg.num_s2m_rings) {
> +			memif_msg_enq_disconnect(pmd->cc, "Invalid ring index",
> +						 0);
> +			return -1;
> +		}
> +		pmd->run.num_s2m_rings++;
> +	} else {
> +		if (ar->index >= pmd->cfg.num_m2s_rings) {
> +			memif_msg_enq_disconnect(pmd->cc, "Invalid ring index",
> +						 0);
> +			return -1;
> +		}
> +		pmd->run.num_m2s_rings++;
> +	}
> +
> +	mq = (ar->flags & MEMIF_MSG_ADD_RING_FLAG_S2M) ?
> +	    &pmd->rx_queues[ar->index] : &pmd->tx_queues[ar->index];
> +
> +	mq->intr_handle.fd = fd;
> +	mq->log2_ring_size = ar->log2_ring_size;
> +	mq->region = ar->region;
> +	mq->offset = ar->offset;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_connect(struct pmd_internals *pmd, memif_msg_t * msg)
> +{
> +	memif_msg_connect_t *c = &msg->connect;
> +	int ret;
> +
> +	ret = memif_connect(pmd);
> +	if (ret < 0)
> +		return ret;
> +
> +	strncpy(pmd->remote_if_name, (char *)c->if_name,
> +		strlen((char *)c->if_name));
> +	MIF_LOG(INFO, "%s: Remote interface %s connected.",
> +		rte_vdev_device_name(pmd->vdev), pmd->remote_if_name);
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_connected(struct pmd_internals *pmd, memif_msg_t * msg)
> +{
> +	memif_msg_connected_t *c = &msg->connected;
> +	int ret;
> +
> +	ret = memif_connect(pmd);
> +	if (ret < 0)
> +		return ret;
> +
> +	strncpy(pmd->remote_if_name, (char *)c->if_name,
> +		strlen((char *)c->if_name));
> +	MIF_LOG(INFO, "%s: Remote interface %s connected.",
> +		rte_vdev_device_name(pmd->vdev), pmd->remote_if_name);
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_receive_disconnect(struct pmd_internals *pmd, memif_msg_t * msg)
> +{
> +	memif_msg_disconnect_t *d = &msg->disconnect;
> +
> +	memset(pmd->remote_disc_string, 0, sizeof(pmd->remote_disc_string));
> +	strncpy(pmd->remote_disc_string, (char *)d->string,
> +		strlen((char *)d->string));
> +
> +	MIF_LOG(INFO, "%s: Disconnect received: %s",
> +		rte_vdev_device_name(pmd->vdev), pmd->remote_disc_string);
> +
> +	memset(pmd->local_disc_string, 0, 96);
> +	memif_disconnect(rte_eth_dev_allocated
> +			 (rte_vdev_device_name(pmd->vdev)));
> +	return 0;
> +}
> +
> +static int memif_msg_enq_ack(struct pmd_internals *pmd)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
> +	if (e == NULL)
> +		return -1;
> +
> +	e->msg.type = MEMIF_MSG_TYPE_ACK;
> +
> +	return 0;
> +}
> +
> +static int memif_msg_enq_init(struct pmd_internals *pmd)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_init_t *i = &e->msg.init;
> +
> +	e->msg.type = MEMIF_MSG_TYPE_INIT;
> +	i->version = MEMIF_VERSION;
> +	i->id = pmd->id;
> +	i->mode = MEMIF_INTERFACE_MODE_ETHERNET;
> +
> +	strncpy((char *)i->name, rte_version(), strlen(rte_version()));
> +
> +	if (pmd->secret) {
> +		strncpy((char *)i->secret, pmd->secret, sizeof(i->secret) - 1);
> +	}
> +
> +	return 0;
> +}
> +
> +static int memif_msg_enq_add_region(struct pmd_internals *pmd, uint8_t idx)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_add_region_t *ar = &e->msg.add_region;
> +	struct memif_region *mr = &pmd->regions[idx];
> +
> +	e->msg.type = MEMIF_MSG_TYPE_ADD_REGION;
> +	e->fd = mr->fd;
> +	ar->index = idx;
> +	ar->size = mr->region_size;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_msg_enq_add_ring(struct pmd_internals *pmd, uint8_t idx,
> +		       memif_ring_type_t type)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_add_ring_t *ar = &e->msg.add_ring;
> +	struct memif_queue *mq;
> +
> +	mq = (type == MEMIF_RING_S2M) ? &pmd->tx_queues[idx] :
> +	    &pmd->rx_queues[idx];
> +
> +	e->msg.type = MEMIF_MSG_TYPE_ADD_RING;
> +	e->fd = mq->intr_handle.fd;
> +	ar->index = idx;
> +	ar->offset = mq->offset;
> +	ar->region = mq->region;
> +	ar->log2_ring_size = mq->log2_ring_size;
> +	ar->flags = (type == MEMIF_RING_S2M) ? MEMIF_MSG_ADD_RING_FLAG_S2M : 0;
> +	ar->private_hdr_size = 0;
> +
> +	return 0;
> +}
> +
> +static int memif_msg_enq_connect(struct pmd_internals *pmd)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_connect_t *c = &e->msg.connect;
> +	const char *name = rte_vdev_device_name(pmd->vdev);
> +
> +	e->msg.type = MEMIF_MSG_TYPE_CONNECT;
> +	strncpy((char *)c->if_name, name, strlen(name));
> +
> +	return 0;
> +}
> +
> +static int memif_msg_enq_connected(struct pmd_internals *pmd)
> +{
> +	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
> +	if (e == NULL)
> +		return -1;
> +
> +	memif_msg_connected_t *c = &e->msg.connected;
> +
> +	const char *name = rte_vdev_device_name(pmd->vdev);
> +
> +	e->msg.type = MEMIF_MSG_TYPE_CONNECTED;
> +	strncpy((char *)c->if_name, name, strlen(name));
> +
> +	return 0;
> +}
> +
> +static void
> +memif_intr_unregister_handler(struct rte_intr_handle *intr_handle, void *arg)
> +{
> +	struct memif_msg_queue_elt *elt;
> +	struct memif_control_channel *cc = arg;
> +	/* close control channel fd */
> +	close(intr_handle->fd);
> +	/* clear message queue */
> +	while ((elt = TAILQ_FIRST(&cc->msg_queue)) != NULL) {
> +		TAILQ_REMOVE(&cc->msg_queue, elt, next);
> +		free(elt);
> +	}
> +	/* free control channel */
> +	rte_free(cc);
> +}
> +
> +void memif_disconnect(struct rte_eth_dev *dev)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_msg_queue_elt *elt;
> +	int i;
> +	int ret;
> +
> +	if (pmd->cc != NULL) {
> +		/* Clear control message queue (except disconnect message if any). */
> +		while ((elt = TAILQ_FIRST(&pmd->cc->msg_queue)) != NULL) {
> +			if (elt->msg.type != MEMIF_MSG_TYPE_DISCONNECT) {
> +				TAILQ_REMOVE(&pmd->cc->msg_queue, elt, next);
> +				free(elt);
> +			}
> +		}
> +		/* send disconnect message (if there is any in queue) */
> +		memif_msg_send_from_queue(pmd->cc);
> +
> +		/* at this point, there should be no more messages in queue */
> +		if (TAILQ_FIRST(&pmd->cc->msg_queue) != NULL) {
> +			MIF_LOG(WARNING,
> +				"%s: Unexpected message(s) in message queue.",
> +				rte_vdev_device_name(pmd->vdev));
> +		}
> +
> +		if (pmd->cc->intr_handle.fd > 0) {
> +			ret =
> +			    rte_intr_callback_unregister(&pmd->cc->intr_handle,
> +							 memif_intr_handler,
> +							 pmd->cc);
> +			/*
> +			 * If callback is active (disconnecting based on
> +			 * received control message).
> +			 */
> +			if (ret == -EAGAIN) {
> +				ret =
> +				    rte_intr_callback_unregister_pending(&pmd->
> +									 cc->
> +									 intr_handle,
> +									 memif_intr_handler,
> +									 pmd->
> +									 cc,
> +									 memif_intr_unregister_handler);
> +			} else if (ret > 0) {
> +				close(pmd->cc->intr_handle.fd);
> +				rte_free(pmd->cc);
> +			}
> +			if (ret <= 0)
> +				MIF_LOG(WARNING,
> +					"%s: Failed to unregister control channel callback.",
> +					rte_vdev_device_name(pmd->vdev));
> +		}
> +	}
> +
> +	/* unconfig interrupts */
> +	struct memif_queue *mq;
> +	for (i = 0; i < pmd->cfg.num_s2m_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +		    &pmd->tx_queues[i] : &pmd->rx_queues[i];
> +		if (mq->intr_handle.fd > 0) {
> +			rte_intr_disable(&mq->intr_handle);
> +			close(mq->intr_handle.fd);
> +			mq->intr_handle.fd = -1;
> +		}
> +		mq->ring = NULL;
> +	}
> +	for (i = 0; i < pmd->cfg.num_m2s_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +		    &pmd->rx_queues[i] : &pmd->tx_queues[i];
> +		if (mq->intr_handle.fd > 0) {
> +			rte_intr_disable(&mq->intr_handle);
> +			close(mq->intr_handle.fd);
> +			mq->intr_handle.fd = -1;
> +		}
> +		mq->ring = NULL;
> +	}
> +
> +	memif_free_regions(pmd);
> +
> +	dev->data->dev_link.link_status = ETH_LINK_DOWN;
> +	pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTING;
> +	pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTED;
> +	MIF_LOG(DEBUG, "%s: Disconnected.", rte_vdev_device_name(pmd->vdev));
> +}
> +
> +static int memif_msg_receive(struct memif_control_channel *cc)
> +{
> +	char ctl[CMSG_SPACE(sizeof(int)) +
> +		 CMSG_SPACE(sizeof(struct ucred))] = { 0 };
> +	struct msghdr mh = { 0 };
> +	struct iovec iov[1];
> +	memif_msg_t msg = { 0 };
> +	ssize_t size;
> +	int ret = 0;
> +	struct ucred *cr __rte_unused;
> +	cr = 0;
> +	struct cmsghdr *cmsg;
> +	int afd = -1;
> +	int i;
> +
> +	iov[0].iov_base = (void *)&msg;
> +	iov[0].iov_len = sizeof(memif_msg_t);
> +	mh.msg_iov = iov;
> +	mh.msg_iovlen = 1;
> +	mh.msg_control = ctl;
> +	mh.msg_controllen = sizeof(ctl);
> +
> +	size = recvmsg(cc->intr_handle.fd, &mh, 0);
> +	if (size != sizeof(memif_msg_t)) {
> +		MIF_LOG(DEBUG, "Invalid message size.");
> +		memif_msg_enq_disconnect(cc, "Invalid message size", 0);
> +		return -1;
> +	}
> +	MIF_LOG(DEBUG, "Received msg type: %u.", msg.type);
> +
> +	cmsg = CMSG_FIRSTHDR(&mh);
> +	while (cmsg) {
> +		if (cmsg->cmsg_level == SOL_SOCKET) {
> +			if (cmsg->cmsg_type == SCM_CREDENTIALS) {
> +				cr = (struct ucred *)CMSG_DATA(cmsg);
> +			} else if (cmsg->cmsg_type == SCM_RIGHTS) {
> +				afd = *(int *)CMSG_DATA(cmsg);
> +			}
> +		}
> +		cmsg = CMSG_NXTHDR(&mh, cmsg);
> +	}
> +
> +	if ((cc->pmd == NULL) && msg.type != MEMIF_MSG_TYPE_INIT) {
> +		MIF_LOG(DEBUG, "Unexpected message.");
> +		memif_msg_enq_disconnect(cc, "Unexpected message", 0);
> +		return -1;
> +	}
> +
> +	/* get device from hash data */
> +	switch (msg.type) {
> +	case MEMIF_MSG_TYPE_ACK:
> +		break;
> +	case MEMIF_MSG_TYPE_HELLO:
> +		ret = memif_msg_receive_hello(cc->pmd, &msg);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_init_regions_and_queues(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_init(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		for (i = 0; i < cc->pmd->regions_num; i++) {
> +			ret = memif_msg_enq_add_region(cc->pmd, i);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		for (i = 0; i < cc->pmd->run.num_s2m_rings; i++) {
> +			ret = memif_msg_enq_add_ring(cc->pmd, i,
> +						     MEMIF_RING_S2M);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		for (i = 0; i < cc->pmd->run.num_m2s_rings; i++) {
> +			ret = memif_msg_enq_add_ring(cc->pmd, i,
> +						     MEMIF_RING_M2S);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		ret = memif_msg_enq_connect(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_INIT:
> +		ret = memif_msg_receive_init(cc, &msg);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_ack(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_ADD_REGION:
> +		ret = memif_msg_receive_add_region(cc->pmd, &msg, afd);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_ack(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_ADD_RING:
> +		ret = memif_msg_receive_add_ring(cc->pmd, &msg, afd);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_ack(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_CONNECT:
> +		ret = memif_msg_receive_connect(cc->pmd, &msg);
> +		if (ret < 0)
> +			goto exit;
> +		ret = memif_msg_enq_connected(cc->pmd);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	case MEMIF_MSG_TYPE_CONNECTED:
> +		ret = memif_msg_receive_connected(cc->pmd, &msg);
> +		break;
> +	case MEMIF_MSG_TYPE_DISCONNECT:
> +		ret = memif_msg_receive_disconnect(cc->pmd, &msg);
> +		if (ret < 0)
> +			goto exit;
> +		break;
> +	default:
> +		memif_msg_enq_disconnect(cc, "Unknown message type", 0);
> +		ret = -1;
> +		goto exit;
> +	}
> +
> + exit:
> +	return ret;
> +}
> +
> +static void memif_intr_handler(void *arg)
> +{
> +	struct memif_control_channel *cc = arg;
> +	struct rte_eth_dev *dev;
> +	int ret;
> +
> +	ret = memif_msg_receive(cc);
> +	/* if driver failed to assign device */
> +	if (cc->pmd == NULL) {
> +		ret = rte_intr_callback_unregister_pending(&cc->intr_handle,
> +							   memif_intr_handler,
> +							   cc,
> +							   memif_intr_unregister_handler);
> +		if (ret < 0)
> +			MIF_LOG(WARNING,
> +				"Failed to unregister control channel callback.");
> +		return;
> +	}
> +	/* if memif_msg_receive failed */
> +	if (ret < 0)
> +		goto disconnect;
> +
> +	ret = memif_msg_send_from_queue(cc);
> +	if (ret < 0)
> +		goto disconnect;
> +
> +	return;
> +
> + disconnect:
> +	dev = rte_eth_dev_allocated(rte_vdev_device_name(cc->pmd->vdev));
> +	if (dev == NULL) {
> +		MIF_LOG(WARNING, "%s: eth dev not allocated",
> +			rte_vdev_device_name(cc->pmd->vdev));
> +		return;
> +	}
> +	memif_disconnect(dev);
> +}
> +
> +static void memif_listener_handler(void *arg)
> +{
> +	struct memif_socket *socket = arg;
> +	int sockfd;
> +	int addr_len;
> +	struct sockaddr_un client;
> +	struct memif_control_channel *cc;
> +	int ret;
> +
> +	addr_len = sizeof(client);
> +	sockfd = accept(socket->intr_handle.fd, (struct sockaddr *)&client,
> +			(socklen_t *) & addr_len);
> +	if (sockfd < 0) {
> +		MIF_LOG(ERR,
> +			"Failed to accept connection request on socket fd %d",
> +			socket->intr_handle.fd);
> +		return;
> +	}
> +
> +	MIF_LOG(DEBUG, "%s: Connection request accepted.", socket->filename);
> +
> +	cc = rte_zmalloc("memif-cc", sizeof(struct memif_control_channel), 0);
> +	if (cc == NULL) {
> +		MIF_LOG(ERR, "Failed to allocate control channel.");
> +		goto error;
> +	}
> +
> +	cc->intr_handle.fd = sockfd;
> +	cc->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +	cc->socket = socket;
> +	cc->pmd = NULL;
> +	TAILQ_INIT(&cc->msg_queue);
> +
> +	ret =
> +	    rte_intr_callback_register(&cc->intr_handle, memif_intr_handler,
> +				       cc);
> +	if (ret < 0) {
> +		MIF_LOG(ERR, "Failed to register control channel callback.");
> +		goto error;
> +	}
> +
> +	ret = memif_msg_enq_hello(cc);
> +	if (ret < 0) {
> +		MIF_LOG(ERR, "Failed to enqueue hello message.");
> +		goto error;
> +	}
> +	ret = memif_msg_send_from_queue(cc);
> +	if (ret < 0)
> +		goto error;
> +
> +	return;
> +
> + error:
> +	if (sockfd > 0) {
> +		close(sockfd);
> +		sockfd = -1;
> +	}
> +	if (cc != NULL) {
> +		rte_free(cc);
> +		cc = NULL;
> +	}
> +}
> +
> +static inline struct memif_socket *memif_socket_create(struct pmd_internals
> +						       *pmd, char *key,
> +						       uint8_t listener)
> +{
> +	struct memif_socket *sock;
> +	struct sockaddr_un un;
> +	int sockfd;
> +	int ret;
> +	int on = 1;
> +
> +	sock = rte_zmalloc("memif-socket", sizeof(struct memif_socket), 0);
> +	if (sock == NULL) {
> +		MIF_LOG(ERR, "Failed to allocate memory for memif socket");
> +		return NULL;
> +	}
> +
> +	sock->listener = listener;
> +	rte_memcpy(sock->filename, key, 256);
> +	TAILQ_INIT(&sock->pmd_queue);
> +
> +	if (listener != 0) {
> +		sockfd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
> +		if (sockfd < 0)
> +			goto error;;
> +
> +		un.sun_family = AF_UNIX;
> +		strncpy((char *)un.sun_path, (char *)sock->filename,
> +			sizeof(un.sun_path) - 1);
> +
> +		ret = setsockopt(sockfd, SOL_SOCKET, SO_PASSCRED, &on,
> +				 sizeof(on));
> +		if (ret < 0) {
> +			goto error;
> +		}
> +		ret = bind(sockfd, (struct sockaddr *)&un, sizeof(un));
> +		if (ret < 0) {
> +			goto error;
> +		}
> +		ret = listen(sockfd, 1);
> +		if (ret < 0) {
> +			goto error;
> +		}
> +
> +		MIF_LOG(DEBUG, "%s: Memif listener socket %s created.",
> +			rte_vdev_device_name(pmd->vdev), sock->filename);
> +
> +		sock->intr_handle.fd = sockfd;
> +		sock->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +		ret = rte_intr_callback_register(&sock->intr_handle,
> +						 memif_listener_handler, sock);
> +		if (ret < 0) {
> +			MIF_LOG(ERR, "%s: Failed to register interrupt "
> +				"callback for listener socket",
> +				rte_vdev_device_name(pmd->vdev));
> +			return NULL;
> +		}
> +	}
> +
> +	return sock;
> +
> + error:
> +	MIF_LOG(ERR, "%s: Failed to setup socket %s: %s",
> +		rte_vdev_device_name(pmd->vdev), key, strerror(errno));
> +	if (sock != NULL)
> +		rte_free(sock);
> +	return NULL;
> +}
> +
> +static inline struct rte_hash *memif_create_socket_hash(void)
> +{
> +	struct rte_hash_parameters params = { 0 };
> +	params.name = MEMIF_SOCKET_HASH_NAME;
> +	params.entries = 256;
> +	params.key_len = 256;
> +	params.hash_func = rte_jhash;
> +	params.hash_func_init_val = 0;
> +	return rte_hash_create(&params);
> +}
> +
> +int memif_socket_init(struct rte_eth_dev *dev, const char *socket_filename)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_socket *socket = NULL;
> +	struct memif_socket_pmd_list_elt *elt;
> +	int ret;
> +	char key[256];
> +
> +	struct rte_hash *hash = rte_hash_find_existing(MEMIF_SOCKET_HASH_NAME);
> +	if (hash == NULL) {
> +		hash = memif_create_socket_hash();
> +		if (hash == NULL) {
> +			MIF_LOG(ERR, "Failed to create memif socket hash.");
> +			return -1;
> +		}
> +	}
> +
> +	memset(key, 0, 256);
> +	rte_memcpy(key, socket_filename, strlen(socket_filename));
> +	ret = rte_hash_lookup_data(hash, key, (void **)&socket);
> +	if (ret < 0) {
> +		socket = memif_socket_create(pmd, key,
> +					     (pmd->role ==
> +					      MEMIF_ROLE_SLAVE) ? 0 : 1);
> +		if (socket == NULL) {
> +			return -1;
> +		}
> +		ret = rte_hash_add_key_data(hash, key, socket);
> +		if (ret < 0) {
> +			MIF_LOG(ERR, "Failed to add socket to socket hash.");
> +			return ret;
> +		}
> +	}
> +	pmd->socket_filename = socket->filename;
> +
> +	if ((socket->listener != 0) && (pmd->role == MEMIF_ROLE_SLAVE)) {
> +		MIF_LOG(ERR, "Socket is a listener.");
> +		return -1;
> +	} else if ((socket->listener == 0) && (pmd->role == MEMIF_ROLE_MASTER)) {
> +		MIF_LOG(ERR, "Socket is not a listener.");
> +		return -1;
> +	}
> +
> +	TAILQ_FOREACH(elt, &socket->pmd_queue, next) {
> +		if (elt->pmd->id == pmd->id) {
> +			MIF_LOG(ERR, "Memif device with id %d already "
> +				"exists on socket %s",
> +				pmd->id, socket->filename);
> +			return -1;
> +		}
> +	}
> +
> +	elt =
> +	    rte_malloc("pmd-queue", sizeof(struct memif_socket_pmd_list_elt),
> +		       0);
> +	if (elt == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to add device to socket device list.",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -1;
> +	}
> +	elt->pmd = pmd;
> +	TAILQ_INSERT_TAIL(&socket->pmd_queue, elt, next);
> +
> +	return 0;
> +}
> +
> +void memif_socket_remove_device(struct pmd_internals *pmd)
> +{
> +	struct memif_socket *socket = NULL;
> +	struct memif_socket_pmd_list_elt *elt, *next;
> +
> +	struct rte_hash *hash = rte_hash_find_existing(MEMIF_SOCKET_HASH_NAME);
> +	if (hash == NULL) {
> +		return;
> +	}
> +
> +	if (rte_hash_lookup_data(hash, pmd->socket_filename, (void **)&socket) <
> +	    0)
> +		return;
> +
> +	for (elt = TAILQ_FIRST(&socket->pmd_queue); elt != NULL; elt = next) {
> +		next = TAILQ_NEXT(elt, next);
> +		if (elt->pmd == pmd) {
> +			TAILQ_REMOVE(&socket->pmd_queue, elt, next);
> +			free(elt);
> +			pmd->socket_filename = NULL;
> +		}
> +	}
> +
> +	/* remove socket, if this was the last device using it */
> +	if (TAILQ_EMPTY(&socket->pmd_queue)) {
> +		rte_hash_del_key(hash, socket->filename);
> +		if (socket->listener) {
> +			/* remove listener socket file,
> +			 * so we can create new one later.
> +			 */
> +			remove(socket->filename);
> +		}
> +		rte_free(socket);
> +	}
> +}
> +
> +int memif_connect_master(struct rte_eth_dev *dev)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	if ((pmd->rx_queues == NULL) || (pmd->tx_queues == NULL) ||
> +	    (pmd->socket_filename == NULL)) {
> +		MIF_LOG(ERR, "%s: Device not configured!",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -1;
> +	}
> +	memset(pmd->local_disc_string, 0, 96);
> +	memset(pmd->remote_disc_string, 0, 96);
> +	pmd->flags &= ~ETH_MEMIF_FLAG_DISABLED;
> +	return 0;
> +}
> +
> +int memif_connect_slave(struct rte_eth_dev *dev)
> +{
> +	int sockfd;
> +	int ret;
> +	struct sockaddr_un sun;
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +
> +	if ((pmd->rx_queues == NULL) || (pmd->tx_queues == NULL) ||
> +	    (pmd->socket_filename == NULL)) {
> +		MIF_LOG(ERR, "%s: Device not configured!",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -1;
> +	}
> +
> +	memset(pmd->local_disc_string, 0, 96);
> +	memset(pmd->remote_disc_string, 0, 96);
> +	pmd->flags &= ~ETH_MEMIF_FLAG_DISABLED;
> +
> +	sockfd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
> +	if (sockfd < 0) {
> +		MIF_LOG(ERR, "%s: Failed to open socket.",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -1;
> +	}
> +
> +	sun.sun_family = AF_UNIX;
> +
> +	strncpy(sun.sun_path, pmd->socket_filename, sizeof(sun.sun_path) - 1);
> +
> +	ret = connect(sockfd, (struct sockaddr *)&sun,
> +		      sizeof(struct sockaddr_un));
> +	if (ret < 0) {
> +		MIF_LOG(ERR, "%s: Failed to connect socket: %s.",
> +			rte_vdev_device_name(pmd->vdev), pmd->socket_filename);
> +		goto error;
> +	}
> +
> +	MIF_LOG(DEBUG, "%s: Memif socket: %s connected.",
> +		rte_vdev_device_name(pmd->vdev), pmd->socket_filename);
> +
> +	pmd->cc = rte_zmalloc("memif-cc",
> +			      sizeof(struct memif_control_channel), 0);
> +	if (pmd->cc == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to allocate control channel.",
> +			rte_vdev_device_name(pmd->vdev));
> +		goto error;
> +	}
> +
> +	pmd->cc->intr_handle.fd = sockfd;
> +	pmd->cc->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +	pmd->cc->socket = NULL;
> +	pmd->cc->pmd = pmd;
> +	TAILQ_INIT(&pmd->cc->msg_queue);
> +
> +	ret = rte_intr_callback_register(&pmd->cc->intr_handle,
> +					 memif_intr_handler, pmd->cc);
> +	if (ret < 0) {
> +		MIF_LOG(ERR, "%s: Failed to register interrupt callback "
> +			"for controll fd", rte_vdev_device_name(pmd->vdev));
> +		goto error;
> +	}
> +
> +	return 0;
> +
> + error:
> +	if (sockfd > 0) {
> +		close(sockfd);
> +		sockfd = -1;
> +	}
> +	if (pmd->cc != NULL) {
> +		rte_free(pmd->cc);
> +		pmd->cc = NULL;
> +	}
> +	return -1;
> +}
> diff --git a/drivers/net/memif/memif_socket.h b/drivers/net/memif/memif_socket.h
> new file mode 100644
> index 000000000..f9136dbe5
> --- /dev/null
> +++ b/drivers/net/memif/memif_socket.h
> @@ -0,0 +1,57 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#ifndef _MEMIF_SOCKET_H_
> +#define _MEMIF_SOCKET_H_
> +
> +#include <sys/queue.h>
> +
> +/*
> + * Remove device from socket device list. If no device is left on the socket,
> + * remove the socket as well.
> + */
> +void memif_socket_remove_device(struct pmd_internals *pmd);
> +
> +void memif_msg_enq_disconnect(struct memif_control_channel *cc,
> +			      const char *reason, int err_code);
> +
> +int memif_socket_init(struct rte_eth_dev *dev, const char *socket_filename);
> +
> +void memif_disconnect(struct rte_eth_dev *dev);
> +
> +/* Allow master to receive connection requests. */
> +int memif_connect_master(struct rte_eth_dev *dev);
> +
> +/* Send connection request. */
> +int memif_connect_slave(struct rte_eth_dev *dev);
> +
> +struct memif_socket_pmd_list_elt {
> +	TAILQ_ENTRY(memif_socket_pmd_list_elt) next;
> +	struct pmd_internals *pmd;
> +};
> +
> +#define MEMIF_SOCKET_HASH_NAME			"memif-sh"
> +struct memif_socket {
> +	struct rte_intr_handle intr_handle;
> +	uint8_t listener;
> +	char filename[256];
> +
> +	 TAILQ_HEAD(, memif_socket_pmd_list_elt) pmd_queue;
> +};
> +
> +/* Control mesage queue. */
> +struct memif_msg_queue_elt {
> +	TAILQ_ENTRY(memif_msg_queue_elt) next;
> +	memif_msg_t msg;
> +	int fd;
> +};
> +
> +struct memif_control_channel {
> +	struct rte_intr_handle intr_handle;
> +	 TAILQ_HEAD(, memif_msg_queue_elt) msg_queue;
> +	struct memif_socket *socket;
> +	struct pmd_internals *pmd;
> +};
> +
> +#endif				/* MEMIF_SOCKET_H */
> diff --git a/drivers/net/memif/meson.build b/drivers/net/memif/meson.build
> new file mode 100644
> index 000000000..ea18394fd
> --- /dev/null
> +++ b/drivers/net/memif/meson.build
> @@ -0,0 +1,8 @@
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> +
> +if host_machine.system() != 'linux'
> +        build = false
> +endif
> +sources = files('rte_eth_memif.c',
> +		'memif_socket.c')
> diff --git a/drivers/net/memif/rte_eth_memif.c b/drivers/net/memif/rte_eth_memif.c
> new file mode 100644
> index 000000000..7988010c4
> --- /dev/null
> +++ b/drivers/net/memif/rte_eth_memif.c
> @@ -0,0 +1,1172 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#include <stdlib.h>
> +#include <fcntl.h>
> +#include <unistd.h>
> +#include <sys/types.h>
> +#include <sys/socket.h>
> +#include <sys/un.h>
> +#include <sys/ioctl.h>
> +#include <sys/mman.h>
> +#include <linux/if_ether.h>
> +#include <errno.h>
> +#include <sys/eventfd.h>
> +
> +#include <rte_version.h>
> +#include <rte_mbuf.h>
> +#include <rte_ether.h>
> +#include <rte_ethdev_driver.h>
> +#include <rte_ethdev_vdev.h>
> +#include <rte_malloc.h>
> +#include <rte_kvargs.h>
> +#include <rte_bus_vdev.h>
> +
> +#include <rte_eth_memif.h>
> +#include <memif_socket.h>
> +
> +#define ETH_MEMIF_ID_ARG		"id"
> +#define ETH_MEMIF_ROLE_ARG		"role"
> +#define ETH_MEMIF_BUFFER_SIZE_ARG	"bsize"
> +#define ETH_MEMIF_RING_SIZE_ARG		"rsize"
> +#define ETH_MEMIF_NRXQ_ARG		"nrxq"
> +#define ETH_MEMIF_NTXQ_ARG		"ntxq"
> +#define ETH_MEMIF_SOCKET_ARG		"socket"
> +#define ETH_MEMIF_MAC_ARG		"mac"
> +#define ETH_MEMIF_ZC_ARG		"zero-copy"
> +#define ETH_MEMIF_SECRET_ARG		"secret"
> +
> +static const char *valid_arguments[] = {
> +	ETH_MEMIF_ID_ARG,
> +	ETH_MEMIF_ROLE_ARG,
> +	ETH_MEMIF_BUFFER_SIZE_ARG,
> +	ETH_MEMIF_RING_SIZE_ARG,
> +	ETH_MEMIF_NRXQ_ARG,
> +	ETH_MEMIF_NTXQ_ARG,
> +	ETH_MEMIF_SOCKET_ARG,
> +	ETH_MEMIF_MAC_ARG,
> +	ETH_MEMIF_ZC_ARG,
> +	ETH_MEMIF_SECRET_ARG,
> +	NULL
> +};
> +
> +static struct rte_vdev_driver pmd_memif_drv;
> +
> +const char *memif_version(void)
> +{
> +#define STR_HELP(s)	#s
> +#define STR(s)		STR_HELP(s)
> +	return ("memif-" STR(MEMIF_VERSION_MAJOR) "." STR(MEMIF_VERSION_MINOR));
> +#undef STR
> +#undef STR_HELP
> +}
> +
> +static void
> +memif_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +
> +	dev_info->if_index = pmd->if_index;
> +	dev_info->max_mac_addrs = 1;
> +	dev_info->max_rx_pktlen = (uint32_t) ETH_FRAME_LEN;
> +	dev_info->max_rx_queues = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +	    pmd->cfg.num_m2s_rings : pmd->cfg.num_s2m_rings;
> +	dev_info->max_tx_queues = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +	    pmd->cfg.num_s2m_rings : pmd->cfg.num_m2s_rings;
> +	dev_info->min_rx_bufsize = 0;
> +}
> +
> +static inline memif_ring_t *memif_get_ring(struct pmd_internals *pmd,
> +					   memif_ring_type_t type,
> +					   uint16_t ring_num)
> +{
> +	/* rings only in region 0 */
> +	void *p = pmd->regions[0].addr;
> +	int ring_size = sizeof(memif_ring_t) + sizeof(memif_desc_t) *
> +	    (1 << pmd->run.log2_ring_size);
> +	p += (ring_num + type * pmd->run.num_s2m_rings) * ring_size;
> +
> +	return (memif_ring_t *) p;
> +}
> +
> +static inline void *memif_get_buffer(struct pmd_internals *pmd,
> +				     memif_desc_t * d)
> +{
> +	return (pmd->regions[d->region].addr + d->offset);
> +}
> +
> +static uint16_t
> +eth_memif_rx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
> +{
> +	struct memif_queue *mq = queue;
> +	struct pmd_internals *pmd = mq->pmd;
> +	if (unlikely((pmd->flags & ETH_MEMIF_FLAG_CONNECTED) == 0))
> +		return 0;
> +	memif_ring_t *ring = mq->ring;
> +	if (unlikely(ring == NULL))
> +		return 0;
> +	uint16_t cur_slot, last_slot, n_slots, ring_size, mask, s0;
> +	uint16_t n_rx_pkts = 0;
> +	uint16_t mbuf_size = rte_pktmbuf_data_room_size(mq->mempool) -
> +	    RTE_PKTMBUF_HEADROOM;
> +	uint16_t src_len, src_off, dst_len, dst_off, cp_len;
> +	memif_ring_type_t type = mq->type;
> +	memif_desc_t *d0;
> +	struct rte_mbuf *mbuf;
> +	struct rte_mbuf *mbuf_head = NULL;
> +
> +	/* consume interrupt */
> +	if ((ring->flags & MEMIF_RING_FLAG_MASK_INT) == 0) {
> +		uint64_t b;
> +		ssize_t size __rte_unused;
> +		size = read(mq->intr_handle.fd, &b, sizeof(b));
> +	}
> +
> +	ring_size = 1 << mq->log2_ring_size;
> +	mask = ring_size - 1;
> +
> +	cur_slot = (type == MEMIF_RING_S2M) ? mq->last_head : mq->last_tail;
> +	last_slot = (type == MEMIF_RING_S2M) ? ring->head : ring->tail;
> +	if (cur_slot == last_slot)
> +		goto refill;
> +	n_slots = last_slot - cur_slot;
> +
> +	while (n_slots && n_rx_pkts < nb_pkts) {
> +		mbuf_head = rte_pktmbuf_alloc(mq->mempool);
> +		if (unlikely(mbuf_head == NULL))
> +			goto no_free_bufs;
> +		mbuf = mbuf_head;
> +		mbuf->port = mq->in_port;
> +
> + next_slot:
> +		s0 = cur_slot & mask;
> +		d0 = &ring->desc[s0];
> +
> +		src_len = d0->length;
> +		dst_off = 0;
> +		src_off = 0;
> +
> +		do {
> +			dst_len = mbuf_size - dst_off;
> +			if (dst_len == 0) {
> +				dst_off = 0;
> +				dst_len = mbuf_size + RTE_PKTMBUF_HEADROOM;
> +
> +				mbuf = rte_pktmbuf_alloc(mq->mempool);
> +				if (unlikely(mbuf == NULL))
> +					goto no_free_bufs;
> +				mbuf->port = mq->in_port;
> +				rte_pktmbuf_chain(mbuf_head, mbuf);
> +			}
> +			cp_len = memif_min(dst_len, src_len);
> +
> +			rte_pktmbuf_pkt_len(mbuf) =
> +			    rte_pktmbuf_data_len(mbuf) += cp_len;
> +
> +			memcpy(rte_pktmbuf_mtod_offset(mbuf, void *, dst_off),
> +			       memif_get_buffer(pmd, d0) + src_off, cp_len);
> +
> +			mq->n_bytes += cp_len;
> +			src_off += cp_len;
> +			dst_off += cp_len;
> +			src_len -= cp_len;
> +		} while (src_len);
> +
> +		cur_slot++;
> +		n_slots--;
> +		if (d0->flags & MEMIF_DESC_FLAG_NEXT) {
> +			goto next_slot;
> +		}
> +
> +		*bufs++ = mbuf_head;
> +		n_rx_pkts++;
> +
> +	}
> +
> + no_free_bufs:
> +	if (type == MEMIF_RING_S2M) {
> +		rte_mb();
> +		ring->tail = mq->last_head = cur_slot;
> +	} else {
> +		mq->last_tail = cur_slot;
> +	}
> +
> + refill:
> +	if (type == MEMIF_RING_M2S) {
> +		uint16_t head = ring->head;
> +		n_slots = ring_size - head + mq->last_tail;
> +
> +		while (n_slots--) {
> +			s0 = head++ & mask;
> +			d0 = &ring->desc[s0];
> +			d0->length = pmd->run.buffer_size;
> +		}
> +		rte_mb();
> +		ring->head = head;
> +	}
> +
> +	mq->n_pkts += n_rx_pkts;
> +	return n_rx_pkts;
> +}
> +
> +static uint16_t
> +eth_memif_tx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
> +{
> +	struct memif_queue *mq = queue;
> +	struct pmd_internals *pmd = mq->pmd;
> +	if (unlikely((pmd->flags & ETH_MEMIF_FLAG_CONNECTED) == 0))
> +		return 0;
> +	memif_ring_t *ring = mq->ring;
> +	if (unlikely(ring == NULL))
> +		return 0;
> +	uint16_t slot, saved_slot, n_free, ring_size, mask, n_tx_pkts = 0;
> +	uint16_t src_len, src_off, dst_len, dst_off, cp_len;
> +	memif_ring_type_t type = mq->type;
> +	memif_desc_t *d0;
> +	struct rte_mbuf *mbuf;
> +	struct rte_mbuf *mbuf_head;
> +
> +	ring_size = 1 << mq->log2_ring_size;
> +	mask = ring_size - 1;
> +
> +	n_free = ring->tail - mq->last_tail;
> +	mq->last_tail += n_free;
> +	slot = (type == MEMIF_RING_S2M) ? ring->head : ring->tail;
> +
> +	if (type == MEMIF_RING_S2M)
> +		n_free = ring_size - ring->head + mq->last_tail;
> +	else
> +		n_free = ring->head - ring->tail;
> +
> +	while (n_free && n_tx_pkts < nb_pkts) {
> +		mbuf_head = *bufs++;
> +		mbuf = mbuf_head;
> +
> +		saved_slot = slot;
> +		d0 = &ring->desc[slot & mask];
> +		dst_off = 0;
> +		dst_len =
> +		    (type ==
> +		     MEMIF_RING_S2M) ? pmd->run.buffer_size : d0->length;
> +
> + next_in_chain:
> +		src_off = 0;
> +		src_len = rte_pktmbuf_data_len(mbuf);
> +
> +		while (src_len) {
> +			if (dst_len == 0) {
> +				if (n_free) {
> +					slot++;
> +					n_free--;
> +					d0->flags |= MEMIF_DESC_FLAG_NEXT;
> +					d0 = &ring->desc[slot & mask];
> +					dst_off = 0;
> +					dst_len = (type == MEMIF_RING_S2M) ?
> +					    pmd->run.buffer_size : d0->length;
> +					d0->flags = 0;
> +				} else {
> +					slot = saved_slot;
> +					goto no_free_slots;
> +				}
> +			}
> +			cp_len = memif_min(dst_len, src_len);
> +
> +			memcpy(memif_get_buffer(pmd, d0) + dst_off,
> +			       rte_pktmbuf_mtod_offset(mbuf, void *, src_off),
> +			       cp_len);
> +
> +			mq->n_bytes += cp_len;
> +			src_off += cp_len;
> +			dst_off += cp_len;
> +			src_len -= cp_len;
> +			dst_len -= cp_len;
> +
> +			d0->length = dst_off;
> +		}
> +
> +		if (rte_pktmbuf_is_contiguous(mbuf) == 0) {
> +			mbuf = mbuf->next;
> +			goto next_in_chain;
> +		}
> +
> +		n_tx_pkts++;
> +		slot++;
> +		n_free--;
> +		rte_pktmbuf_free(mbuf_head);
> +	}
> +
> + no_free_slots:
> +	rte_mb();
> +	if (type == MEMIF_RING_S2M)
> +		ring->head = slot;
> +	else
> +		ring->tail = slot;
> +
> +	if ((ring->flags & MEMIF_RING_FLAG_MASK_INT) == 0) {
> +		uint64_t a = 1;
> +		ssize_t size = write(mq->intr_handle.fd, &a, sizeof(a));
> +		if (unlikely(size < 0)) {
> +			MIF_LOG(WARNING,
> +				"%s: Failed to send interrupt on qid %ld: %s",
> +				rte_vdev_device_name(pmd->vdev),
> +				mq - pmd->tx_queues, strerror(errno));
> +		}
> +	}
> +
> +	mq->n_err += nb_pkts - n_tx_pkts;
> +	mq->n_pkts += n_tx_pkts;
> +	return n_tx_pkts;
> +}
> +
> +void memif_free_regions(struct pmd_internals *pmd)
> +{
> +	int i;
> +	struct memif_region *r;
> +
> +	for (i = 0; i < pmd->regions_num; i++) {
> +		r = pmd->regions + i;
> +		if (r == NULL)
> +			return;
> +		if (r->addr == NULL)
> +			return;
> +		munmap(r->addr, r->region_size);
> +		if (r->fd > 0) {
> +			close(r->fd);
> +			r->fd = -1;
> +		}
> +	}
> +	rte_free(pmd->regions);
> +}
> +
> +static int memif_alloc_regions(struct pmd_internals *pmd, uint8_t brn)
> +{
> +	struct memif_region *r;
> +	char shm_name[32];
> +	int i;
> +	int ret = 0;
> +
> +	r = rte_zmalloc("memif_region", sizeof(struct memif_region) * (brn + 1),
> +			0);
> +	if (r == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to allocate regions.",
> +			rte_vdev_device_name(pmd->vdev));
> +		return -ENOMEM;
> +	}
> +
> +	pmd->regions = r;
> +	pmd->regions_num = brn + 1;
> +
> +	/*
> +	 * Create shm for every region. Region 0 is reserved for descriptors.
> +	 * Other regions contain buffers.
> +	 */
> +	for (i = 0; i < (brn + 1); i++) {
> +		r = &pmd->regions[i];
> +
> +		r->buffer_offset = (i == 0) ? (pmd->run.num_s2m_rings +
> +					       pmd->run.num_m2s_rings) *
> +		    (sizeof(memif_ring_t) +
> +		     sizeof(memif_desc_t) * (1 << pmd->run.log2_ring_size)) : 0;
> +		r->region_size = (i == 0) ? r->buffer_offset :
> +		    (uint32_t) (pmd->run.buffer_size *
> +				(1 << pmd->run.log2_ring_size) *
> +				(pmd->run.num_s2m_rings +
> +				 pmd->run.num_m2s_rings));
> +
> +		memset(shm_name, 0, sizeof(char) * 32);
> +		sprintf(shm_name, "memif region %d", i);
> +
> +		r->fd = memfd_create(shm_name, MFD_ALLOW_SEALING);
> +		if (r->fd < 0) {
> +			MIF_LOG(ERR, "%s: Failed to create shm file: %s.",
> +				rte_vdev_device_name(pmd->vdev),
> +				strerror(errno));
> +			return -1;
> +		}
> +
> +		ret = fcntl(r->fd, F_ADD_SEALS, F_SEAL_SHRINK);
> +		if (ret < 0) {
> +			MIF_LOG(ERR, "%s: Failed to add seals to shm file: %s.",
> +				rte_vdev_device_name(pmd->vdev),
> +				strerror(errno));
> +			return -1;
> +		}
> +
> +		ret = ftruncate(r->fd, r->region_size);
> +		if (ret < 0) {
> +			MIF_LOG(ERR, "%s: Failed to truncate shm file: %s.",
> +				rte_vdev_device_name(pmd->vdev),
> +				strerror(errno));
> +			return -1;
> +		}
> +
> +		r->addr = mmap(NULL, r->region_size, PROT_READ |
> +			       PROT_WRITE, MAP_SHARED, r->fd, 0);
> +		if (r->addr == NULL) {
> +			MIF_LOG(ERR, "%s: Failed to mmap shm region: %s.",
> +				rte_vdev_device_name(pmd->vdev),
> +				strerror(errno));
> +			return -1;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static void memif_init_rings(struct pmd_internals *pmd)
> +{
> +	memif_ring_t *ring;
> +	int i, j;
> +
> +	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
> +		ring = memif_get_ring(pmd, MEMIF_RING_S2M, i);
> +		ring->head = ring->tail = 0;
> +		ring->cookie = MEMIF_COOKIE;
> +		ring->flags = 0;
> +		for (j = 0; j < (1 << pmd->run.log2_ring_size); j++) {
> +			uint16_t slot = i * (1 << pmd->run.log2_ring_size) + j;
> +			ring->desc[j].region = 1;
> +			ring->desc[j].offset = pmd->regions[1].buffer_offset +
> +			    (uint32_t) (slot * pmd->run.buffer_size);
> +			ring->desc[j].length = pmd->run.buffer_size;
> +		}
> +	}
> +
> +	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
> +		ring = memif_get_ring(pmd, MEMIF_RING_M2S, i);
> +		ring->head = ring->tail = 0;
> +		ring->cookie = MEMIF_COOKIE;
> +		ring->flags = 0;
> +		for (j = 0; j < (1 << pmd->run.log2_ring_size); j++) {
> +			uint16_t slot = (i + pmd->run.num_s2m_rings) *
> +			    (1 << pmd->run.log2_ring_size) + j;
> +			ring->desc[j].region = 1;
> +			ring->desc[j].offset = pmd->regions[1].buffer_offset +
> +			    (uint32_t) (slot * pmd->run.buffer_size);
> +			ring->desc[j].length = pmd->run.buffer_size;
> +		}
> +	}
> +}
> +
> +static void memif_init_queues(struct pmd_internals *pmd)
> +{
> +	struct memif_queue *mq;
> +	int i;
> +
> +	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
> +		mq = &pmd->tx_queues[i];
> +		mq->ring = memif_get_ring(pmd, MEMIF_RING_S2M, i);
> +		mq->log2_ring_size = pmd->run.log2_ring_size;
> +		/* queues located only in region 0 */
> +		mq->region = 0;
> +		mq->offset = (void *)mq->ring - (void *)pmd->regions[0].addr;
> +		mq->last_head = mq->last_tail = 0;
> +		mq->intr_handle.fd = eventfd(0, EFD_NONBLOCK);
> +		if (mq->intr_handle.fd < 0) {
> +			MIF_LOG(WARNING,
> +				"%s: Failed to create eventfd for tx queue %d: %s.",
> +				rte_vdev_device_name(pmd->vdev), i,
> +				strerror(errno));
> +		}
> +	}
> +
> +	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
> +		mq = &pmd->rx_queues[i];
> +		mq->ring = memif_get_ring(pmd, MEMIF_RING_M2S, i);
> +		mq->log2_ring_size = pmd->run.log2_ring_size;
> +		/* queues located only in region 0 */
> +		mq->region = 0;
> +		mq->offset = (void *)mq->ring - (void *)pmd->regions[0].addr;
> +		mq->last_head = mq->last_tail = 0;
> +		mq->intr_handle.fd = eventfd(0, EFD_NONBLOCK);
> +		if (mq->intr_handle.fd < 0) {
> +			MIF_LOG(WARNING,
> +				"%s: Failed to create eventfd for rx queue %d: %s.",
> +				rte_vdev_device_name(pmd->vdev), i,
> +				strerror(errno));
> +		}
> +	}
> +}
> +
> +int memif_init_regions_and_queues(struct pmd_internals *pmd)
> +{
> +	int ret;
> +
> +	ret = memif_alloc_regions(pmd, /* num of buffer regions */ 1);
> +	if (ret < 0) {
> +		return ret;
> +	}
> +
> +	memif_init_rings(pmd);
> +
> +	memif_init_queues(pmd);
> +
> +	return 0;
> +}
> +
> +int memif_connect(struct pmd_internals *pmd)
> +{
> +	struct rte_eth_dev *eth_dev =
> +	    rte_eth_dev_allocated(rte_vdev_device_name(pmd->vdev));
> +	struct memif_region *mr;
> +	struct memif_queue *mq;
> +	int i;
> +
> +	for (i = 0; i < pmd->regions_num; i++) {
> +		mr = pmd->regions + i;
> +		if (mr != NULL) {
> +			if (mr->addr == NULL) {
> +				if (mr->fd < 0)
> +					return -1;
> +				mr->addr = mmap(NULL, mr->region_size,
> +						PROT_READ | PROT_WRITE,
> +						MAP_SHARED, mr->fd, 0);
> +				if (mr->addr == NULL)
> +					return -1;
> +			}
> +		}
> +	}
> +
> +	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +		    &pmd->tx_queues[i] : &pmd->rx_queues[i];
> +		mq->ring = pmd->regions[mq->region].addr + mq->offset;
> +		if (mq->ring->cookie != MEMIF_COOKIE) {
> +			MIF_LOG(ERR, "%s: Wrong cookie",
> +				rte_vdev_device_name(pmd->vdev));
> +			return -1;
> +		}
> +		mq->ring->head = mq->ring->tail = mq->last_head =
> +		    mq->last_tail = 0;
> +		/* polling mode by default */
> +		if (pmd->role == MEMIF_ROLE_MASTER) {
> +			mq->ring->flags = MEMIF_RING_FLAG_MASK_INT;
> +		}
> +	}
> +	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
> +		    &pmd->rx_queues[i] : &pmd->tx_queues[i];
> +		mq->ring = pmd->regions[mq->region].addr + mq->offset;
> +		if (mq->ring->cookie != MEMIF_COOKIE) {
> +			MIF_LOG(ERR, "%s: Wrong cookie",
> +				rte_vdev_device_name(pmd->vdev));
> +			return -1;
> +		}
> +		mq->ring->head = mq->ring->tail = mq->last_head =
> +		    mq->last_tail = 0;
> +		/* polling mode by default */
> +		if (pmd->role == MEMIF_ROLE_SLAVE) {
> +			mq->ring->flags = MEMIF_RING_FLAG_MASK_INT;
> +		}
> +	}
> +
> +	pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTING;
> +	pmd->flags |= ETH_MEMIF_FLAG_CONNECTED;
> +	eth_dev->data->dev_link.link_status = ETH_LINK_UP;
> +	MIF_LOG(INFO, "%s: Connected.", rte_vdev_device_name(pmd->vdev));
> +	return 0;
> +}
> +
> +static int memif_dev_start(struct rte_eth_dev *dev)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	int ret = 0;
> +
> +	switch (pmd->role) {
> +	case MEMIF_ROLE_SLAVE:
> +		ret = memif_connect_slave(dev);
> +		break;
> +	case MEMIF_ROLE_MASTER:
> +		ret = memif_connect_master(dev);
> +		break;
> +	default:
> +		MIF_LOG(ERR, "%s: Unknown role: %d.",
> +			rte_vdev_device_name(pmd->vdev), pmd->role);
> +		ret = -1;
> +		break;
> +	}
> +
> +	return ret;
> +}
> +
> +static int memif_dev_configure(struct rte_eth_dev *dev __rte_unused)
> +{
> +	return 0;
> +}
> +
> +static int
> +memif_tx_queue_setup(struct rte_eth_dev *dev,
> +		     uint16_t qid,
> +		     uint16_t nb_tx_desc __rte_unused,
> +		     unsigned int socket_id __rte_unused,
> +		     const struct rte_eth_txconf *tx_conf __rte_unused)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_queue *mq;
> +
> +	mq = rte_realloc(pmd->tx_queues, sizeof(struct memif_queue) * (qid + 1),
> +			 0);
> +	if (mq == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to alloc tx queue %u.",
> +			rte_vdev_device_name(pmd->vdev), qid);
> +		return -ENOMEM;
> +	}
> +
> +	pmd->tx_queues = mq;
> +
> +	mq->type =
> +	    (pmd->role == MEMIF_ROLE_SLAVE) ? MEMIF_RING_S2M : MEMIF_RING_M2S;
> +	mq->n_pkts = 0;
> +	mq->n_bytes = 0;
> +	mq->n_err = 0;
> +	mq->intr_handle.fd = -1;
> +	mq->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +	mq->pmd = pmd;
> +	dev->data->tx_queues[qid] = mq;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_rx_queue_setup(struct rte_eth_dev *dev,
> +		     uint16_t qid,
> +		     uint16_t nb_rx_desc __rte_unused,
> +		     unsigned int socket_id __rte_unused,
> +		     const struct rte_eth_rxconf *rx_conf __rte_unused,
> +		     struct rte_mempool *mb_pool)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_queue *mq;
> +
> +	mq = rte_realloc(pmd->rx_queues, sizeof(struct memif_queue) * (qid + 1),
> +			 0);
> +	if (mq == NULL) {
> +		MIF_LOG(ERR, "%s: Failed to alloc rx queue %u.",
> +			rte_vdev_device_name(pmd->vdev), qid);
> +		return -ENOMEM;
> +	}
> +
> +	pmd->rx_queues = mq;
> +
> +	mq->type =
> +	    (pmd->role == MEMIF_ROLE_SLAVE) ? MEMIF_RING_M2S : MEMIF_RING_S2M;
> +	mq->n_pkts = 0;
> +	mq->n_bytes = 0;
> +	mq->n_err = 0;
> +	mq->intr_handle.fd = -1;
> +	mq->intr_handle.type = RTE_INTR_HANDLE_EXT;
> +	mq->mempool = mb_pool;
> +	mq->in_port = dev->data->port_id;
> +	mq->pmd = pmd;
> +	dev->data->rx_queues[qid] = mq;
> +
> +	return 0;
> +}
> +
> +static int
> +memif_link_update(struct rte_eth_dev *dev __rte_unused,
> +		  int wait_to_complete __rte_unused)
> +{
> +	return 0;
> +}
> +
> +static int memif_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *stats)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	struct memif_queue *mq;
> +	int i;
> +
> +	stats->ipackets = 0;
> +	stats->ibytes = 0;
> +	stats->opackets = 0;
> +	stats->obytes = 0;
> +	stats->oerrors = 0;
> +
> +	uint8_t tmp = (pmd->role == MEMIF_ROLE_SLAVE) ? pmd->run.num_s2m_rings :
> +	    pmd->run.num_m2s_rings;
> +	uint8_t nq = (tmp < RTE_ETHDEV_QUEUE_STAT_CNTRS) ? tmp :
> +	    RTE_ETHDEV_QUEUE_STAT_CNTRS;
> +
> +	/* RX stats */
> +	for (i = 0; i < nq; i++) {
> +		mq = &pmd->rx_queues[i];
> +		stats->q_ipackets[i] = mq->n_pkts;
> +		stats->q_ibytes[i] = mq->n_bytes;
> +		stats->ipackets += mq->n_pkts;
> +		stats->ibytes += mq->n_bytes;
> +	}
> +
> +	tmp = (pmd->role == MEMIF_ROLE_SLAVE) ? pmd->run.num_m2s_rings :
> +	    pmd->run.num_s2m_rings;
> +	nq = (tmp < RTE_ETHDEV_QUEUE_STAT_CNTRS) ? tmp :
> +	    RTE_ETHDEV_QUEUE_STAT_CNTRS;
> +
> +	/* TX stats */
> +	for (i = 0; i < nq; i++) {
> +		mq = &pmd->tx_queues[i];
> +		stats->q_opackets[i] = mq->n_pkts;
> +		stats->q_obytes[i] = mq->n_bytes;
> +		stats->q_errors[i] = mq->n_err;
> +		stats->opackets += mq->n_pkts;
> +		stats->obytes += mq->n_bytes;
> +		stats->oerrors += mq->n_err;
> +	}
> +	return 0;
> +}
> +
> +static void memif_stats_reset(struct rte_eth_dev *dev)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +	int i;
> +	struct memif_queue *mq;
> +
> +	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ? &pmd->tx_queues[i] :
> +		    &pmd->rx_queues[i];
> +		mq->n_pkts = 0;
> +		mq->n_bytes = 0;
> +		mq->n_err = 0;
> +	}
> +	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
> +		mq = (pmd->role == MEMIF_ROLE_SLAVE) ? &pmd->rx_queues[i] :
> +		    &pmd->tx_queues[i];
> +		mq->n_pkts = 0;
> +		mq->n_bytes = 0;
> +		mq->n_err = 0;
> +	}
> +}
> +
> +static int
> +memif_rx_queue_intr_enable(struct rte_eth_dev *dev, uint16_t qid __rte_unused)
> +{
> +	struct pmd_internals *pmd = dev->data->dev_private;
> +
> +	MIF_LOG(WARNING, "%s: Interrupt mode not supported.",
> +		rte_vdev_device_name(pmd->vdev));
> +
> +	/* Enable MEMIF interrupts. */
> +	/* pmd->rx_queues[qid].ring->flags  &= ~MEMIF_RING_FLAG_MASK_INT; */
> +
> +	/*
> +	 * TODO: Tell dpdk to use interrupt mode.
> +	 *
> +	 * return rte_intr_enable(&pmd->rx_queues[qid].intr_handle);
> +	 */
> +	return -1;
> +}
> +
> +static int
> +memif_rx_queue_intr_disable(struct rte_eth_dev *dev, uint16_t qid __rte_unused)
> +{
> +	struct pmd_internals *pmd __rte_unused = dev->data->dev_private;
> +
> +	/* Disable MEMIF interrupts. */
> +	/* pmd->rx_queues[qid].ring->flags |= MEMIF_RING_FLAG_MASK_INT; */
> +
> +	/*
> +	 * TODO: Tell dpdk to use polling mode.
> +	 *
> +	 * return rte_intr_disable(&pmd->rx_queues[qid].intr_handle);
> +	 */
> +	return 0;
> +}
> +
> +static const struct eth_dev_ops ops = {
> +	.dev_start = memif_dev_start,
> +	.dev_infos_get = memif_dev_info,
> +	.dev_configure = memif_dev_configure,
> +	.tx_queue_setup = memif_tx_queue_setup,
> +	.rx_queue_setup = memif_rx_queue_setup,
> +	.rx_queue_intr_enable = memif_rx_queue_intr_enable,
> +	.rx_queue_intr_disable = memif_rx_queue_intr_disable,
> +	.link_update = memif_link_update,
> +	.stats_get = memif_stats_get,
> +	.stats_reset = memif_stats_reset,
> +};
> +
> +static int
> +memif_create(struct rte_vdev_device *vdev, enum memif_role_t role,
> +	     memif_interface_id_t id, uint32_t flags,
> +	     const char *socket_filename,
> +	     memif_log2_ring_size_t log2_ring_size, uint8_t nrxq,
> +	     uint8_t ntxq, uint16_t buffer_size, const char *secret,
> +	     const char *eth_addr)
> +{
> +	int ret = 0;
> +	struct rte_eth_dev *eth_dev;
> +	struct rte_eth_dev_data *data;
> +	struct pmd_internals *pmd;
> +	const unsigned int numa_node = vdev->device.numa_node;
> +	const char *name = rte_vdev_device_name(vdev);
> +
> +	if (flags & ETH_MEMIF_FLAG_ZERO_COPY) {
> +		MIF_LOG(ERR, "Zero-copy not supported.");
> +		return -1;
> +	}
> +
> +	eth_dev = rte_eth_vdev_allocate(vdev, sizeof(*pmd));
> +	if (eth_dev == NULL) {
> +		MIF_LOG(ERR, "%s: Unable to allocate device struct.", name);
> +		return -1;
> +	}
> +
> +	pmd = eth_dev->data->dev_private;
> +	memset(pmd, 0, sizeof(*pmd));
> +
> +	pmd->if_index = id;
> +	pmd->vdev = vdev;
> +	pmd->id = id;
> +	pmd->flags = flags;
> +	pmd->flags |= ETH_MEMIF_FLAG_DISABLED;
> +	pmd->role = role;
> +	ret = memif_socket_init(eth_dev, socket_filename);
> +	if (ret < 0)
> +		return ret;
> +
> +	memset(pmd->secret, 0, sizeof(char) * 24);
> +	if (secret != NULL)
> +		strncpy(pmd->secret, secret,
> +			(strlen(secret) >= 24) ? 24 : strlen(secret));
> +
> +	pmd->cfg.log2_ring_size = ETH_MEMIF_DEFAULT_RING_SIZE;
> +	if (log2_ring_size != 0)
> +		pmd->cfg.log2_ring_size = log2_ring_size;
> +	pmd->cfg.num_s2m_rings = ETH_MEMIF_DEFAULT_NRXQ;
> +	pmd->cfg.num_m2s_rings = ETH_MEMIF_DEFAULT_NTXQ;
> +
> +	if (nrxq != 0) {
> +		if (role == MEMIF_ROLE_SLAVE)
> +			pmd->cfg.num_m2s_rings = nrxq;
> +		else
> +			pmd->cfg.num_s2m_rings = nrxq;
> +	}
> +	if (ntxq != 0) {
> +		if (role == MEMIF_ROLE_SLAVE)
> +			pmd->cfg.num_s2m_rings = ntxq;
> +		else
> +			pmd->cfg.num_m2s_rings = ntxq;
> +	}
> +
> +	pmd->cfg.buffer_size = ETH_MEMIF_DEFAULT_BUFFER_SIZE;
> +	if (buffer_size != 0)
> +		pmd->cfg.buffer_size = buffer_size;
> +
> +	/* FIXME: generate mac? */
> +	if (eth_addr == NULL)
> +		eth_addr = ETH_MEMIF_DEFAULT_ETH_ADDR;
> +
> +	sscanf(eth_addr, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
> +	       &pmd->eth_addr.addr_bytes[0], &pmd->eth_addr.addr_bytes[1],
> +	       &pmd->eth_addr.addr_bytes[2], &pmd->eth_addr.addr_bytes[3],
> +	       &pmd->eth_addr.addr_bytes[4], &pmd->eth_addr.addr_bytes[5]);
> +
> +	data = eth_dev->data;
> +	data->dev_private = pmd;
> +	data->numa_node = numa_node;
> +	data->mac_addrs = &pmd->eth_addr;
> +
> +	eth_dev->dev_ops = &ops;
> +	eth_dev->device = &vdev->device;
> +	eth_dev->rx_pkt_burst = eth_memif_rx;
> +	eth_dev->tx_pkt_burst = eth_memif_tx;
> +
> +	rte_eth_dev_probing_finish(eth_dev);
> +
> +	return ret;
> +}
> +
> +static int
> +memif_set_role(const char *key __rte_unused, const char *value,
> +	       void *extra_args)
> +{
> +	enum memif_role_t *role = (enum memif_role_t *)extra_args;
> +	if (strstr(value, "master") != NULL) {
> +		*role = MEMIF_ROLE_MASTER;
> +	} else if (strstr(value, "slave") != NULL) {
> +		*role = MEMIF_ROLE_SLAVE;
> +	} else {
> +		MIF_LOG(ERR, "Unknown role: %s.", value);
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int
> +memif_set_zc(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	uint32_t *flags = (uint32_t *) extra_args;
> +
> +	if (strstr(value, "yes") != NULL) {
> +		*flags |= ETH_MEMIF_FLAG_ZERO_COPY;
> +	} else if (strstr(value, "no") != NULL) {
> +		*flags &= ~ETH_MEMIF_FLAG_ZERO_COPY;
> +	} else {
> +		MIF_LOG(ERR, "Failed to parse zero-copy param: %s.", value);
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int
> +memif_set_id(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	memif_interface_id_t *id = (memif_interface_id_t *) extra_args;
> +	/* even if parsing fails, 0 is a valid id */
> +	*id = strtoul(value, NULL, 10);
> +	return 0;
> +}
> +
> +static int
> +memif_set_bs(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	unsigned long int tmp;
> +	uint16_t *buffer_size = (uint16_t *) extra_args;
> +
> +	tmp = strtoul(value, NULL, 10);
> +	if ((tmp == 0) || (tmp > 0xFFFF)) {
> +		MIF_LOG(ERR, "Invalid buffer size: %s.", value);
> +		return -EINVAL;
> +	}
> +	*buffer_size = tmp;
> +	return 0;
> +}
> +
> +static int
> +memif_set_rs(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	unsigned long int tmp;
> +	memif_log2_ring_size_t *log2_ring_size =
> +	    (memif_log2_ring_size_t *) extra_args;
> +
> +	tmp = strtoul(value, NULL, 10);
> +	if ((tmp == 0) || (tmp > ETH_MEMIF_MAX_LOG2_RING_SIZE)) {
> +		MIF_LOG(ERR, "Invalid ring size: %s (max %u).",
> +			value, ETH_MEMIF_MAX_LOG2_RING_SIZE);
> +		return -EINVAL;
> +	}
> +	*log2_ring_size = tmp;
> +	return 0;
> +}
> +
> +static int
> +memif_set_nq(const char *key __rte_unused, const char *value, void *extra_args)
> +{
> +	unsigned long int tmp;
> +	uint16_t *nq = (uint16_t *) extra_args;
> +
> +	tmp = strtoul(value, NULL, 10);
> +	if ((tmp == 0) || (tmp > 0xFF)) {
> +		MIF_LOG(ERR, "Invalid number of queues: %s.", value);
> +		return -EINVAL;
> +	}
> +	*nq = tmp;
> +	return 0;
> +}
> +
> +/* check if directory exists and if we have permission to read/write */
> +static inline int memif_check_socket_filename(const char *filename)
> +{
> +	char *dir = NULL, *tmp;
> +	uint32_t idx;
> +	int ret = 0;
> +
> +	tmp = strrchr(filename, '/');
> +	if (tmp != NULL) {
> +		idx = tmp - filename;
> +		dir = rte_zmalloc("memif_tmp", sizeof(char) * (idx + 2), 0);
> +		if (dir == NULL) {
> +			MIF_LOG(ERR, "Failed to allocate memory.");
> +			return -1;
> +		}
> +		strncpy(dir, filename, idx);
> +	}
> +
> +	if ((dir == NULL) || (faccessat(-1, dir, F_OK | R_OK |
> +					W_OK, AT_EACCESS) < 0)) {
> +		MIF_LOG(ERR, "Invalid directory: %s.", dir);
> +		ret = -EINVAL;
> +	}
> +
> +	if (dir != NULL)
> +		rte_free(dir);
> +
> +	return ret;
> +}
> +
> +static int rte_pmd_memif_probe(struct rte_vdev_device *vdev)
> +{
> +	int ret = 0;
> +	unsigned int i;
> +	struct rte_kvargs *kvlist;
> +	const struct rte_kvargs_pair *pair;
> +
> +	const char *name = rte_vdev_device_name(vdev);
> +
> +	enum memif_role_t role;
> +	memif_interface_id_t id;
> +
> +	uint16_t buffer_size;
> +	memif_log2_ring_size_t log2_ring_size;
> +	uint8_t nrxq, ntxq;
> +	const char *socket_filename;
> +	const char *eth_addr;
> +	uint32_t flags;
> +	const char *secret;
> +
> +	MIF_LOG(INFO, "Initialize MEMIF: %s.", name);
> +
> +	kvlist = rte_kvargs_parse(rte_vdev_device_args(vdev), valid_arguments);
> +
> +	/* set default values */
> +	role = MEMIF_ROLE_SLAVE;
> +	flags = 0;
> +	id = 0;
> +	buffer_size = 2048;
> +	log2_ring_size = 10;
> +	nrxq = 1;
> +	ntxq = 1;
> +	socket_filename = ETH_MEMIF_DEFAULT_SOCKET_FILENAME;
> +	secret = NULL;
> +	eth_addr = NULL;
> +
> +	/* parse parameters */
> +	if (kvlist != NULL) {
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_ROLE_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_ROLE_ARG,
> +						 &memif_set_role, &role);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_ID_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_ID_ARG,
> +						 &memif_set_id, &id);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_BUFFER_SIZE_ARG) == 1) {
> +			ret =
> +			    rte_kvargs_process(kvlist,
> +					       ETH_MEMIF_BUFFER_SIZE_ARG,
> +					       &memif_set_bs, &buffer_size);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_RING_SIZE_ARG) == 1) {
> +			ret =
> +			    rte_kvargs_process(kvlist, ETH_MEMIF_RING_SIZE_ARG,
> +					       &memif_set_rs, &log2_ring_size);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_NRXQ_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_NRXQ_ARG,
> +						 &memif_set_nq, &nrxq);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_NTXQ_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_NTXQ_ARG,
> +						 &memif_set_nq, &ntxq);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_SOCKET_ARG) == 1) {
> +			for (i = 0; i < kvlist->count; i++) {
> +				pair = &kvlist->pairs[i];
> +				if (strcmp(pair->key, ETH_MEMIF_SOCKET_ARG) ==
> +				    0) {
> +					socket_filename = pair->value;
> +					ret =
> +					    memif_check_socket_filename
> +					    (socket_filename);
> +					if (ret < 0)
> +						goto exit;
> +				}
> +			}
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_MAC_ARG) == 1) {
> +			for (i = 0; i < kvlist->count; i++) {
> +				pair = &kvlist->pairs[i];
> +				if (strcmp(pair->key, ETH_MEMIF_MAC_ARG) == 0) {
> +					eth_addr = pair->value;
> +				}
> +			}
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_ZC_ARG) == 1) {
> +			ret = rte_kvargs_process(kvlist, ETH_MEMIF_ZC_ARG,
> +						 &memif_set_zc, &flags);
> +			if (ret < 0)
> +				goto exit;
> +		}
> +		if (rte_kvargs_count(kvlist, ETH_MEMIF_SECRET_ARG) == 1) {
> +			for (i = 0; i < kvlist->count; i++) {
> +				pair = &kvlist->pairs[i];
> +				if (strcmp(pair->key, ETH_MEMIF_SECRET_ARG) ==
> +				    0) {
> +					secret = pair->value;
> +				}
> +			}
> +		}
> +	}
> +
> +	/* create interface */
> +	ret =
> +	    memif_create(vdev, role, id, flags, socket_filename, log2_ring_size,
> +			 nrxq, ntxq, buffer_size, secret, eth_addr);
> +
> + exit:
> +	if (kvlist != NULL)
> +		rte_kvargs_free(kvlist);
> +	return ret;
> +}
> +
> +static int rte_pmd_memif_remove(struct rte_vdev_device *vdev)
> +{
> +	struct rte_eth_dev *eth_dev;
> +
> +	eth_dev = rte_eth_dev_allocated(rte_vdev_device_name(vdev));
> +	if (eth_dev == NULL)
> +		return 0;
> +
> +	struct pmd_internals *pmd = eth_dev->data->dev_private;
> +
> +	memif_msg_enq_disconnect(pmd->cc, "Invalid message size", 0);
> +	memif_disconnect(eth_dev);
> +
> +	memif_socket_remove_device(pmd);
> +
> +	pmd->vdev = NULL;
> +
> +	rte_free(eth_dev->data->dev_private);
> +
> +	rte_eth_dev_release_port(eth_dev);
> +
> +	return 0;
> +}
> +
> +static struct rte_vdev_driver pmd_memif_drv = {
> +	.probe = rte_pmd_memif_probe,
> +	.remove = rte_pmd_memif_remove,
> +};
> +
> +RTE_PMD_REGISTER_VDEV(net_memif, pmd_memif_drv);
> +RTE_PMD_REGISTER_ALIAS(net_memif, eth_memif);
> +RTE_PMD_REGISTER_PARAM_STRING(net_memif,
> +			      ETH_MEMIF_ID_ARG "=<int>"
> +			      ETH_MEMIF_ROLE_ARG "=<string>"
> +			      ETH_MEMIF_BUFFER_SIZE_ARG "=<int>"
> +			      ETH_MEMIF_RING_SIZE_ARG "=<int>"
> +			      ETH_MEMIF_NRXQ_ARG "=<int>"
> +			      ETH_MEMIF_NTXQ_ARG "=<int>"
> +			      ETH_MEMIF_SOCKET_ARG "=<string>"
> +			      ETH_MEMIF_MAC_ARG "=xx:xx:xx:xx:xx:xx"
> +			      ETH_MEMIF_ZC_ARG "=<string>"
> +			      ETH_MEMIF_SECRET_ARG "=<string>");
> +
> +RTE_INIT(memif_init_log)
> +{
> +	memif_logtype = rte_log_register("pmd.net.memif");
> +	if (memif_logtype >= 0)
> +		rte_log_set_level(memif_logtype, RTE_LOG_NOTICE);
> +}
> diff --git a/drivers/net/memif/rte_eth_memif.h b/drivers/net/memif/rte_eth_memif.h
> new file mode 100644
> index 000000000..bbd79e1a5
> --- /dev/null
> +++ b/drivers/net/memif/rte_eth_memif.h
> @@ -0,0 +1,189 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
> + */
> +
> +#ifndef _RTE_ETH_MEMIF_H_
> +#define _RTE_ETH_MEMIF_H_
> +
> +#ifndef _GNU_SOURCE
> +#define _GNU_SOURCE
> +#endif				/* GNU_SOURCE */
> +
> +#include <stdio.h>
> +#include <sys/queue.h>
> +
> +#include <rte_ethdev_driver.h>
> +#include <rte_ether.h>
> +#include <rte_timer.h>
> +#include <rte_interrupts.h>
> +
> +#include <memif.h>
> +
> +/* generate mac? */
> +#define ETH_MEMIF_DEFAULT_ETH_ADDR		"01:ab:23:cd:45:ef"
> +
> +#define ETH_MEMIF_DEFAULT_SOCKET_FILENAME	"/tmp/memif.sock"
> +#define ETH_MEMIF_DEFAULT_RING_SIZE		10
> +#define ETH_MEMIF_DEFAULT_NRXQ			1
> +#define ETH_MEMIF_DEFAULT_NTXQ			1
> +#define ETH_MEMIF_DEFAULT_BUFFER_SIZE		2048
> +
> +#define ETH_MEMIF_MAX_NUM_Q_PAIRS		256
> +#define ETH_MEMIF_MAX_LOG2_RING_SIZE		14
> +#define ETH_MEMIF_MAX_REGION_IDX		255
> +
> +int memif_logtype;
> +
> +#define memif_min(a,b) (((a) < (b)) ? (a) : (b))
> +
> +#define MIF_LOG(level, fmt, args...) \
> +do {							\
> +	rte_log(RTE_LOG_ ## level, memif_logtype,	\
> +		"%s(): " fmt "\n", __func__, ##args);	\
> +} while (0)
> +
> +enum memif_role_t {
> +	MEMIF_ROLE_MASTER = 0,
> +	MEMIF_ROLE_SLAVE = 1,
> +};
> +
> +/* Shared memory region. */
> +struct memif_region {
> +	void *addr;
> +	memif_region_size_t region_size;
> +	int fd;
> +	uint32_t buffer_offset;
> +};
> +
> +struct memif_queue {
> +	struct rte_mempool *mempool;
> +	uint16_t in_port;
> +
> +	struct pmd_internals *pmd;
> +
> +	struct rte_intr_handle intr_handle;
> +
> +	/* ring info */
> +	memif_ring_type_t type;
> +	memif_ring_t *ring;
> +	memif_log2_ring_size_t log2_ring_size;
> +
> +	memif_region_index_t region;
> +	memif_region_offset_t offset;
> +
> +	uint16_t last_head;
> +	uint16_t last_tail;
> +	uint32_t *buffers;
> +
> +	/* rx/tx info */
> +	uint64_t n_pkts;
> +	uint64_t n_bytes;
> +	uint64_t n_err;
> +};
> +
> +struct pmd_internals {
> +	int if_index;
> +	memif_interface_id_t id;
> +	enum memif_role_t role;
> +	uint32_t flags;
> +#define ETH_MEMIF_FLAG_CONNECTING	(1 << 0)
> +#define ETH_MEMIF_FLAG_CONNECTED	(1 << 1)
> +#define ETH_MEMIF_FLAG_ZERO_COPY	(1 << 2)
> +/* device has not been configured and can not accept connection requests */
> +#define ETH_MEMIF_FLAG_DISABLED		(1 << 3)
> +
> +	struct ether_addr eth_addr;
> +	char *socket_filename;
> +	char secret[24];
> +
> +	struct memif_control_channel *cc;
> +
> +	struct memif_region *regions;
> +	uint8_t regions_num;
> +
> +	struct memif_queue *rx_queues;
> +	struct memif_queue *tx_queues;
> +
> +	/* remote info */
> +	char remote_name[64];
> +	char remote_if_name[64];
> +
> +	/* Configured parameters (max values) */
> +	struct {
> +		memif_log2_ring_size_t log2_ring_size;
> +		uint8_t num_s2m_rings;
> +		uint8_t num_m2s_rings;
> +		uint16_t buffer_size;
> +	} cfg;
> +
> +	/* Parameters used in active connection */
> +	struct {
> +		memif_log2_ring_size_t log2_ring_size;
> +		uint8_t num_s2m_rings;
> +		uint8_t num_m2s_rings;
> +		uint16_t buffer_size;
> +	} run;
> +
> +	char local_disc_string[96];
> +	char remote_disc_string[96];
> +
> +	/* vdev handle */
> +	struct rte_vdev_device *vdev;
> +};
> +
> +void memif_free_regions(struct pmd_internals *pmd);
> +
> +/*
> + * Finalize connection establishment process. Map shared memory file
> + * (master role), initialize ring queue, set link status up.
> + */
> +int memif_connect(struct pmd_internals *pmd);
> +
> +/*
> + * Create shared memory file and initialize ring queue.
> + * Only called by slave when establishing connection
> + */
> +int memif_init_regions_and_queues(struct pmd_internals *pmd);
> +
> +const char *memif_version(void);
> +
> +#ifndef MFD_HUGETLB
> +#ifndef __NR_memfd_create
> +
> +#if defined __x86_64__
> +#define __NR_memfd_create 319
> +#elif defined __arm__
> +#define __NR_memfd_create 385
> +#elif defined __aarch64__
> +#define __NR_memfd_create 279
> +#else
> +#error "__NR_memfd_create unknown for this architecture"
> +#endif
> +
> +#endif				/* __NR_memfd_create */
> +
> +static inline int memfd_create(const char *name, unsigned int flags)
> +{
> +	return syscall(__NR_memfd_create, name, flags);
> +}
> +#endif				/* MFD_HUGETLB */
> +
> +#ifndef F_LINUX_SPECIFIC_BASE
> +#define F_LINUX_SPECIFIC_BASE 1024
> +#endif
> +
> +#ifndef MFD_ALLOW_SEALING
> +#define MFD_ALLOW_SEALING       0x0002U
> +#endif
> +
> +#ifndef F_ADD_SEALS
> +#define F_ADD_SEALS (F_LINUX_SPECIFIC_BASE + 9)
> +#define F_GET_SEALS (F_LINUX_SPECIFIC_BASE + 10)
> +
> +#define F_SEAL_SEAL     0x0001	/* prevent further seals from being set */
> +#define F_SEAL_SHRINK   0x0002	/* prevent file from shrinking */
> +#define F_SEAL_GROW     0x0004	/* prevent file from growing */
> +#define F_SEAL_WRITE    0x0008	/* prevent writes */
> +#endif
> +
> +#endif				/* RTE_ETH_MEMIF_H */
> diff --git a/drivers/net/memif/rte_pmd_memif_version.map b/drivers/net/memif/rte_pmd_memif_version.map
> new file mode 100644
> index 000000000..aee560afa
> --- /dev/null
> +++ b/drivers/net/memif/rte_pmd_memif_version.map
> @@ -0,0 +1,4 @@
> +DPDK_2.0 {
> +
> +        local: *;
> +};
> diff --git a/drivers/net/meson.build b/drivers/net/meson.build
> index 980eec233..b0becbf31 100644
> --- a/drivers/net/meson.build
> +++ b/drivers/net/meson.build
> @@ -21,6 +21,7 @@ drivers = ['af_packet',
>  	'ixgbe',
>  	'kni',
>  	'liquidio',
> +	'memif',
>  	'mlx4',
>  	'mlx5',
>  	'mvneta',
> diff --git a/mk/rte.app.mk b/mk/rte.app.mk
> index 5699d979d..f236c5ebc 100644
> --- a/mk/rte.app.mk
> +++ b/mk/rte.app.mk
> @@ -168,6 +168,7 @@ ifeq ($(CONFIG_RTE_LIBRTE_KNI),y)
>  _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_KNI)        += -lrte_pmd_kni
>  endif
>  _LDLIBS-$(CONFIG_RTE_LIBRTE_LIO_PMD)        += -lrte_pmd_lio
> +_LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF)      += -lrte_pmd_memif
>  ifeq ($(CONFIG_RTE_LIBRTE_MLX4_DLOPEN_DEPS),y)
>  _LDLIBS-$(CONFIG_RTE_LIBRTE_MLX4_PMD)       += -lrte_pmd_mlx4 -ldl
>  else
> --
> 2.17.1
  
Burakov, Anatoly Dec. 12, 2018, 10:19 a.m. UTC | #7
On 10-Dec-18 10:50 AM, Richardson, Bruce wrote:
> 
> 
>> -----Original Message-----
>> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Burakov, Anatoly
>> Sent: Monday, December 10, 2018 10:43 AM
>> To: Jakub Grajciar <jgrajcia@cisco.com>; dev@dpdk.org
>> Subject: Re: [dpdk-dev] [RFC v2] /net: memory interface (memif)
>>
>> On 10-Dec-18 10:06 AM, Jakub Grajciar wrote:
>>> Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
>>> ---
>>
>> As a general comment, some description/cover letter would have been nice.
>>
>>> +
>>> +	memif_msg_disconnect_t *d = &e->msg.disconnect;
>>> +
>>> +	e->msg.type = MEMIF_MSG_TYPE_DISCONNECT;
>>> +	d->code = err_code;
>>> +
>>> +	if (reason != NULL) {
>>> +		strncpy((char *)d->string, reason, strlen(reason));
>>> +		if (cc->pmd != NULL) {
>>> +			strncpy(cc->pmd->local_disc_string, reason,
>>> +				strlen(reason));
>>> +		}
>>
>> I haven't looked at the entire thing, this is just something that caught
>> my eye during quick skimming through code.
>>
>> On the face of it, this looks dangerous - you're setting the destination
>> buffer size from source buffer size. What if `d->string` is shorter than
>> `reason`?
>>
> 
> And strncpy is dangerous - use strlcpy instead.

Isn't strscpy the string copy function du jour now? :)

> 
> /Bruce
>
  
Bruce Richardson Dec. 12, 2018, 10:30 a.m. UTC | #8
On Wed, Dec 12, 2018 at 10:19:02AM +0000, Burakov, Anatoly wrote:
> On 10-Dec-18 10:50 AM, Richardson, Bruce wrote:
> > 
> > 
> > > -----Original Message-----
> > > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Burakov, Anatoly
> > > Sent: Monday, December 10, 2018 10:43 AM
> > > To: Jakub Grajciar <jgrajcia@cisco.com>; dev@dpdk.org
> > > Subject: Re: [dpdk-dev] [RFC v2] /net: memory interface (memif)
> > > 
> > > On 10-Dec-18 10:06 AM, Jakub Grajciar wrote:
> > > > Signed-off-by: Jakub Grajciar <jgrajcia@cisco.com>
> > > > ---
> > > 
> > > As a general comment, some description/cover letter would have been nice.
> > > 
> > > > +
> > > > +	memif_msg_disconnect_t *d = &e->msg.disconnect;
> > > > +
> > > > +	e->msg.type = MEMIF_MSG_TYPE_DISCONNECT;
> > > > +	d->code = err_code;
> > > > +
> > > > +	if (reason != NULL) {
> > > > +		strncpy((char *)d->string, reason, strlen(reason));
> > > > +		if (cc->pmd != NULL) {
> > > > +			strncpy(cc->pmd->local_disc_string, reason,
> > > > +				strlen(reason));
> > > > +		}
> > > 
> > > I haven't looked at the entire thing, this is just something that caught
> > > my eye during quick skimming through code.
> > > 
> > > On the face of it, this looks dangerous - you're setting the destination
> > > buffer size from source buffer size. What if `d->string` is shorter than
> > > `reason`?
> > > 
> > 
> > And strncpy is dangerous - use strlcpy instead.
> 
> Isn't strscpy the string copy function du jour now? :)
> 
Well, it's certainly the new one! It's only available as a DPDK-specific
function though - "rte_strscpy". Therefore, I think strlcpy is generally
preferred, but either will do.

/Bruce
  
Honnappa Nagarahalli Dec. 17, 2018, 4:26 a.m. UTC | #9
> >
> >> On Dec 10, 2018, at 4:06 AM, Jakub Grajciar <jgrajcia@cisco.com> wrote:
> >
> > I do not like being the coding style police, but that is most of the comments
> here and I will try to test this one later this week. Plus I am sure I missed some
> style problems, if you have not read the coding style for DPDK please have a
> read.
> >
> > http://doc.dpdk.org/guides/contributing/coding_style.html
> >
> > One comment, why did you include all of the code to handle memif instead
> of including the libmemif.a from VPP. I worry if libmemif is changed then we
> have a breakage. I do not mind the PMD being standalone and I do like not
> having the dependence.
Just for my understanding, do you mean to say we could include the libmemif.a as a binary in DPDK?

IMO, I would like to view DPDK as the device abstraction and VPP as the protocol stack built on top. From this perspective, it is good to have standalone memif in DPDK.

> >
> > As I did not dive into the code much it does look reasonable and I hope to
> give it a try later this week.
> >>
> 
> A couple more items, do you plan on writing the documentation for the PMD
> and provide an example program?
+1, would be good to have a cover letter.
I would like to run this on Arm platforms, mostly in the beginning of Jan.

> 
> Regards,
> Keith
  
Honnappa Nagarahalli Dec. 17, 2018, 4:54 a.m. UTC | #10
> > >> On Dec 10, 2018, at 4:06 AM, Jakub Grajciar <jgrajcia@cisco.com> wrote:
> > >
> > > I do not like being the coding style police, but that is most of the
> > > comments
> > here and I will try to test this one later this week. Plus I am sure I
> > missed some style problems, if you have not read the coding style for
> > DPDK please have a read.
> > >
> > > http://doc.dpdk.org/guides/contributing/coding_style.html
> > >
> > > One comment, why did you include all of the code to handle memif
> > > instead
> > of including the libmemif.a from VPP. I worry if libmemif is changed
> > then we have a breakage. I do not mind the PMD being standalone and I
> > do like not having the dependence.
> Just for my understanding, do you mean to say we could include the
> libmemif.a as a binary in DPDK?
> 
> IMO, I would like to view DPDK as the device abstraction and VPP as the
> protocol stack built on top. From this perspective, it is good to have
> standalone memif in DPDK.
> 
> > >
> > > As I did not dive into the code much it does look reasonable and I
> > > hope to
> > give it a try later this week.
> > >>
> >
> > A couple more items, do you plan on writing the documentation for the
> > PMD and provide an example program?
> +1, would be good to have a cover letter.
Please ignore, I already see V3 having some documentation.

> I would like to run this on Arm platforms, mostly in the beginning of Jan.
> 
> >
> > Regards,
> > Keith
  

Patch

diff --git a/config/common_base b/config/common_base
index d12ae98bc..b8ed10ae5 100644
--- a/config/common_base
+++ b/config/common_base
@@ -403,6 +403,11 @@  CONFIG_RTE_LIBRTE_VMXNET3_DEBUG_TX_FREE=n
 #
 CONFIG_RTE_LIBRTE_PMD_AF_PACKET=n
 
+#
+# Compile Memory Interface PMD driver (Linux only)
+#
+CONFIG_RTE_LIBRTE_PMD_MEMIF=n
+
 #
 # Compile link bonding PMD library
 #
diff --git a/config/common_linuxapp b/config/common_linuxapp
index 6c1c8d0f4..42cbde8f5 100644
--- a/config/common_linuxapp
+++ b/config/common_linuxapp
@@ -18,6 +18,7 @@  CONFIG_RTE_LIBRTE_VHOST_POSTCOPY=n
 CONFIG_RTE_LIBRTE_PMD_VHOST=y
 CONFIG_RTE_LIBRTE_IFC_PMD=y
 CONFIG_RTE_LIBRTE_PMD_AF_PACKET=y
+CONFIG_RTE_LIBRTE_PMD_MEMIF=y
 CONFIG_RTE_LIBRTE_PMD_SOFTNIC=y
 CONFIG_RTE_LIBRTE_PMD_TAP=y
 CONFIG_RTE_LIBRTE_AVP_PMD=y
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index c0386feb9..0feab5241 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -32,6 +32,7 @@  DIRS-$(CONFIG_RTE_LIBRTE_FM10K_PMD) += fm10k
 DIRS-$(CONFIG_RTE_LIBRTE_I40E_PMD) += i40e
 DIRS-$(CONFIG_RTE_LIBRTE_IXGBE_PMD) += ixgbe
 DIRS-$(CONFIG_RTE_LIBRTE_LIO_PMD) += liquidio
+DIRS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += memif
 DIRS-$(CONFIG_RTE_LIBRTE_MLX4_PMD) += mlx4
 DIRS-$(CONFIG_RTE_LIBRTE_MLX5_PMD) += mlx5
 DIRS-$(CONFIG_RTE_LIBRTE_MVNETA_PMD) += mvneta
diff --git a/drivers/net/memif/Makefile b/drivers/net/memif/Makefile
new file mode 100644
index 000000000..a82448423
--- /dev/null
+++ b/drivers/net/memif/Makefile
@@ -0,0 +1,29 @@ 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright 2018 Cisco Systems, Inc.  All rights reserved.
+
+include $(RTE_SDK)/mk/rte.vars.mk
+
+#
+# library name
+#
+LIB = librte_pmd_memif.a
+
+EXPORT_MAP := rte_pmd_memif_version.map
+
+LIBABIVER := 1
+
+CFLAGS += -O3
+CFLAGS += -I$(SRCDIR)
+CFLAGS += $(WERROR_FLAGS)
+CFLAGS += -Wno-pointer-arith
+LDLIBS += -lrte_eal -lrte_mbuf -lrte_mempool -lrte_ring
+LDLIBS += -lrte_ethdev -lrte_net -lrte_kvargs
+LDLIBS += -lrte_bus_vdev
+
+#
+# all source are stored in SRCS-y
+#
+SRCS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += rte_eth_memif.c
+SRCS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF) += memif_socket.c
+
+include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/drivers/net/memif/memif.h b/drivers/net/memif/memif.h
new file mode 100644
index 000000000..6a23dbad7
--- /dev/null
+++ b/drivers/net/memif/memif.h
@@ -0,0 +1,156 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
+ */
+
+#ifndef _MEMIF_H_
+#define _MEMIF_H_
+
+#ifndef MEMIF_CACHELINE_SIZE
+#define MEMIF_CACHELINE_SIZE 64
+#endif
+
+#define MEMIF_COOKIE		0x3E31F20
+#define MEMIF_VERSION_MAJOR	2
+#define MEMIF_VERSION_MINOR	0
+#define MEMIF_VERSION		((MEMIF_VERSION_MAJOR << 8) | MEMIF_VERSION_MINOR)
+
+/*
+ *  Type definitions
+ */
+
+typedef enum memif_msg_type {
+	MEMIF_MSG_TYPE_NONE = 0,
+	MEMIF_MSG_TYPE_ACK = 1,
+	MEMIF_MSG_TYPE_HELLO = 2,
+	MEMIF_MSG_TYPE_INIT = 3,
+	MEMIF_MSG_TYPE_ADD_REGION = 4,
+	MEMIF_MSG_TYPE_ADD_RING = 5,
+	MEMIF_MSG_TYPE_CONNECT = 6,
+	MEMIF_MSG_TYPE_CONNECTED = 7,
+	MEMIF_MSG_TYPE_DISCONNECT = 8,
+} memif_msg_type_t;
+
+typedef enum {
+	MEMIF_RING_S2M = 0,
+	MEMIF_RING_M2S = 1
+} memif_ring_type_t;
+
+typedef enum {
+	MEMIF_INTERFACE_MODE_ETHERNET = 0,
+	MEMIF_INTERFACE_MODE_IP = 1,
+	MEMIF_INTERFACE_MODE_PUNT_INJECT = 2,
+} memif_interface_mode_t;
+
+typedef uint16_t memif_region_index_t;
+typedef uint32_t memif_region_offset_t;
+typedef uint64_t memif_region_size_t;
+typedef uint16_t memif_ring_index_t;
+typedef uint32_t memif_interface_id_t;
+typedef uint16_t memif_version_t;
+typedef uint8_t memif_log2_ring_size_t;
+
+/*
+ *  Socket messages
+ */
+
+typedef struct __attribute__ ((packed)) {
+	uint8_t name[32];
+	memif_version_t min_version;
+	memif_version_t max_version;
+	memif_region_index_t max_region;
+	memif_ring_index_t max_m2s_ring;
+	memif_ring_index_t max_s2m_ring;
+	memif_log2_ring_size_t max_log2_ring_size;
+} memif_msg_hello_t;
+
+typedef struct __attribute__ ((packed)) {
+	memif_version_t version;
+	memif_interface_id_t id;
+	memif_interface_mode_t mode:8;
+	uint8_t secret[24];
+	uint8_t name[32];
+} memif_msg_init_t;
+
+typedef struct __attribute__ ((packed)) {
+	memif_region_index_t index;
+	memif_region_size_t size;
+} memif_msg_add_region_t;
+
+typedef struct __attribute__ ((packed)) {
+	uint16_t flags;
+#define MEMIF_MSG_ADD_RING_FLAG_S2M	(1 << 0)
+	memif_ring_index_t index;
+	memif_region_index_t region;
+	memif_region_offset_t offset;
+	memif_log2_ring_size_t log2_ring_size;
+	uint16_t private_hdr_size;	/* used for private metadata */
+} memif_msg_add_ring_t;
+
+typedef struct __attribute__ ((packed)) {
+	uint8_t if_name[32];
+} memif_msg_connect_t;
+
+typedef struct __attribute__ ((packed)) {
+	uint8_t if_name[32];
+} memif_msg_connected_t;
+
+typedef struct __attribute__ ((packed)) {
+	uint32_t code;
+	uint8_t string[96];
+} memif_msg_disconnect_t;
+
+typedef struct __attribute__ ((packed, aligned(128))) {
+	memif_msg_type_t type:16;
+	union {
+		memif_msg_hello_t hello;
+		memif_msg_init_t init;
+		memif_msg_add_region_t add_region;
+		memif_msg_add_ring_t add_ring;
+		memif_msg_connect_t connect;
+		memif_msg_connected_t connected;
+		memif_msg_disconnect_t disconnect;
+	};
+} memif_msg_t;
+
+_Static_assert(sizeof(memif_msg_t) == 128, "Size of memif_msg_t must be 128");
+
+/*
+ *  Ring and Descriptor Layout
+ */
+
+typedef struct __attribute__ ((packed)) {
+	uint16_t flags;
+#define MEMIF_DESC_FLAG_NEXT (1 << 0)
+	memif_region_index_t region;
+	uint32_t length;
+	memif_region_offset_t offset;
+	uint32_t metadata;
+} memif_desc_t;
+
+_Static_assert(sizeof(memif_desc_t) == 16,
+	       "Size of memif_dsct_t must be 16 bytes");
+
+#define MEMIF_CACHELINE_ALIGN_MARK(mark) \
+  uint8_t mark[0] __attribute__((aligned(MEMIF_CACHELINE_SIZE)))
+
+typedef struct {
+	MEMIF_CACHELINE_ALIGN_MARK(cacheline0);
+	uint32_t cookie;
+	uint16_t flags;
+#define MEMIF_RING_FLAG_MASK_INT 1
+	volatile uint16_t head;
+	 MEMIF_CACHELINE_ALIGN_MARK(cacheline1);
+	volatile uint16_t tail;
+	 MEMIF_CACHELINE_ALIGN_MARK(cacheline2);
+	memif_desc_t desc[0];
+} memif_ring_t;
+
+#endif				/* _MEMIF_H_ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/drivers/net/memif/memif_socket.c b/drivers/net/memif/memif_socket.c
new file mode 100644
index 000000000..afd4ac888
--- /dev/null
+++ b/drivers/net/memif/memif_socket.c
@@ -0,0 +1,1085 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
+ */
+
+#include <stdlib.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+
+#include <rte_version.h>
+#include <rte_mbuf.h>
+#include <rte_ether.h>
+#include <rte_ethdev_driver.h>
+#include <rte_ethdev_vdev.h>
+#include <rte_malloc.h>
+#include <rte_kvargs.h>
+#include <rte_bus_vdev.h>
+#include <rte_hash.h>
+#include <rte_jhash.h>
+
+#include <rte_eth_memif.h>
+#include <memif_socket.h>
+
+static void memif_intr_handler(void *arg);
+
+static inline ssize_t memif_msg_send(int fd, memif_msg_t * msg, int afd)
+{
+	struct msghdr mh = { 0 };
+	struct iovec iov[1];
+	char ctl[CMSG_SPACE(sizeof(int))];
+
+	iov[0].iov_base = (void *)msg;
+	iov[0].iov_len = sizeof(memif_msg_t);
+	mh.msg_iov = iov;
+	mh.msg_iovlen = 1;
+
+	if (afd > 0) {
+		struct cmsghdr *cmsg;
+		memset(&ctl, 0, sizeof(ctl));
+		mh.msg_control = ctl;
+		mh.msg_controllen = sizeof(ctl);
+		cmsg = CMSG_FIRSTHDR(&mh);
+		cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+		cmsg->cmsg_level = SOL_SOCKET;
+		cmsg->cmsg_type = SCM_RIGHTS;
+		rte_memcpy(CMSG_DATA(cmsg), &afd, sizeof(int));
+	}
+
+	return sendmsg(fd, &mh, 0);
+}
+
+static inline int memif_msg_send_from_queue(struct memif_control_channel *cc)
+{
+	ssize_t size;
+	int ret = 0;
+	struct memif_msg_queue_elt *e;
+	e = TAILQ_FIRST(&cc->msg_queue);
+	if (e == NULL)
+		return 0;
+
+	size = memif_msg_send(cc->intr_handle.fd, &e->msg, e->fd);
+	if (size != sizeof(memif_msg_t)) {
+		MIF_LOG(ERR, "sendmsg fail: %s.", strerror(errno));
+		ret = -1;
+	} else {
+		MIF_LOG(DEBUG, "%s: Sent msg type %u.",
+			(cc->pmd !=
+			 NULL) ? rte_vdev_device_name(cc->pmd->
+						      vdev) : "memif_driver",
+			e->msg.type);
+	}
+	TAILQ_REMOVE(&cc->msg_queue, e, next);
+	rte_free(e);
+
+	return ret;
+}
+
+static inline struct memif_msg_queue_elt *memif_msg_enq(struct
+							memif_control_channel
+							*cc)
+{
+	struct memif_msg_queue_elt *e = rte_zmalloc("memif_msg",
+						    sizeof(struct
+							   memif_msg_queue_elt),
+						    0);
+	if (e == NULL) {
+		MIF_LOG(ERR, "Failed to allocate control message.");
+		return NULL;
+	}
+
+	e->fd = -1;
+	TAILQ_INSERT_TAIL(&cc->msg_queue, e, next);
+
+	return e;
+}
+
+void
+memif_msg_enq_disconnect(struct memif_control_channel *cc, const char *reason,
+			 int err_code)
+{
+	struct memif_msg_queue_elt *e = memif_msg_enq(cc);
+	if (e == NULL) {
+		MIF_LOG(WARNING, "%s: Failed to enqueue disconnect message.",
+			(cc->pmd !=
+			 NULL) ? rte_vdev_device_name(cc->pmd->
+						      vdev) : "memif_driver");
+		return;
+	}
+
+	memif_msg_disconnect_t *d = &e->msg.disconnect;
+
+	e->msg.type = MEMIF_MSG_TYPE_DISCONNECT;
+	d->code = err_code;
+
+	if (reason != NULL) {
+		strncpy((char *)d->string, reason, strlen(reason));
+		if (cc->pmd != NULL) {
+			strncpy(cc->pmd->local_disc_string, reason,
+				strlen(reason));
+		}
+	}
+}
+
+static int memif_msg_enq_hello(struct memif_control_channel *cc)
+{
+	struct memif_msg_queue_elt *e = memif_msg_enq(cc);
+	if (e == NULL)
+		return -1;
+
+	memif_msg_hello_t *h = &e->msg.hello;
+
+	e->msg.type = MEMIF_MSG_TYPE_HELLO;
+	h->min_version = MEMIF_VERSION;
+	h->max_version = MEMIF_VERSION;
+	h->max_s2m_ring = ETH_MEMIF_MAX_NUM_Q_PAIRS;
+	h->max_m2s_ring = ETH_MEMIF_MAX_NUM_Q_PAIRS;
+	h->max_region = ETH_MEMIF_MAX_REGION_IDX;
+	h->max_log2_ring_size = ETH_MEMIF_MAX_LOG2_RING_SIZE;
+
+	strncpy((char *)h->name, rte_version(), strlen(rte_version()));
+
+	return 0;
+}
+
+static int memif_msg_receive_hello(struct pmd_internals *pmd, memif_msg_t * msg)
+{
+	memif_msg_hello_t *h = &msg->hello;
+
+	if (h->min_version > MEMIF_VERSION || h->max_version < MEMIF_VERSION) {
+		memif_msg_enq_disconnect(pmd->cc, "Incompatible memif version",
+					 0);
+		return -1;
+	}
+
+	/* Set parameters for active connection */
+	pmd->run.num_s2m_rings = memif_min(h->max_s2m_ring + 1,
+					   pmd->cfg.num_s2m_rings);
+	pmd->run.num_m2s_rings = memif_min(h->max_m2s_ring + 1,
+					   pmd->cfg.num_m2s_rings);
+	pmd->run.log2_ring_size = memif_min(h->max_log2_ring_size,
+					    pmd->cfg.log2_ring_size);
+	pmd->run.buffer_size = pmd->cfg.buffer_size;
+
+	strncpy(pmd->remote_name, (char *)h->name, strlen((char *)h->name));
+
+	MIF_LOG(DEBUG, "%s: Connecting to %s.",
+		rte_vdev_device_name(pmd->vdev), pmd->remote_name);
+
+	return 0;
+}
+
+static int
+memif_msg_receive_init(struct memif_control_channel *cc, memif_msg_t * msg)
+{
+	memif_msg_init_t *i = &msg->init;
+	struct memif_socket_pmd_list_elt *elt;
+	struct pmd_internals *pmd;
+
+	if (i->version != MEMIF_VERSION) {
+		memif_msg_enq_disconnect(cc, "Incompatible memif version", 0);
+		return -1;
+	}
+
+	if (cc->socket == NULL) {
+		memif_msg_enq_disconnect(cc, "Device error", 0);
+		return -1;
+	}
+
+	/* Find device with requested ID */
+	TAILQ_FOREACH(elt, &cc->socket->pmd_queue, next) {
+		pmd = elt->pmd;
+		if (((pmd->flags & ETH_MEMIF_FLAG_DISABLED) == 0)
+		    && (pmd->id == i->id)) {
+			/* assign control channel to device */
+			cc->pmd = pmd;
+			pmd->cc = cc;
+
+			if (i->mode != MEMIF_INTERFACE_MODE_ETHERNET) {
+				memif_msg_enq_disconnect(pmd->cc,
+							 "Only ethernet mode supported",
+							 0);
+				return -1;
+			}
+
+			if (pmd->flags && (ETH_MEMIF_FLAG_CONNECTING |
+					   ETH_MEMIF_FLAG_CONNECTED)) {
+				memif_msg_enq_disconnect(pmd->cc,
+							 "Already connected",
+							 0);
+				return -1;
+			}
+			strncpy(pmd->remote_name, (char *)i->name,
+				strlen((char *)i->name));
+
+			if (*pmd->secret != '\0') {
+				if (*i->secret == '\0') {
+					memif_msg_enq_disconnect(pmd->cc,
+								 "Secret required",
+								 0);
+					return -1;
+				}
+				if (strcmp(pmd->secret, (char *)i->secret) != 0) {
+					memif_msg_enq_disconnect(pmd->cc,
+								 "Incorrect secret",
+								 0);
+					return -1;
+				}
+			}
+
+			pmd->flags |= ETH_MEMIF_FLAG_CONNECTING;
+			return 0;
+		}
+	}
+
+	/* ID not found on this socket */
+	MIF_LOG(DEBUG, "ID %u not found.", i->id);
+	memif_msg_enq_disconnect(cc, "ID not found", 0);
+	return -1;
+}
+
+static int
+memif_msg_receive_add_region(struct pmd_internals *pmd, memif_msg_t * msg,
+			     int fd)
+{
+	memif_msg_add_region_t *ar = &msg->add_region;
+
+	if (fd < 0) {
+		memif_msg_enq_disconnect(pmd->cc, "Missing region fd", 0);
+		return -1;
+	}
+
+	struct memif_region *mr;
+
+	if (ar->index > ETH_MEMIF_MAX_REGION_IDX) {
+		memif_msg_enq_disconnect(pmd->cc, "Invalid region index", 0);
+		return -1;
+	}
+
+	mr = rte_realloc(pmd->regions, sizeof(struct memif_region) *
+			 (ar->index + 1), 0);
+	if (mr == NULL) {
+		memif_msg_enq_disconnect(pmd->cc, "Device error", 0);
+		return -1;
+	}
+
+	pmd->regions = mr;
+	pmd->regions[ar->index].fd = fd;
+	pmd->regions[ar->index].region_size = ar->size;
+	pmd->regions[ar->index].addr = NULL;
+	pmd->regions_num++;
+
+	return 0;
+}
+
+static int
+memif_msg_receive_add_ring(struct pmd_internals *pmd, memif_msg_t * msg, int fd)
+{
+	memif_msg_add_ring_t *ar = &msg->add_ring;
+
+	if (fd < 0) {
+		memif_msg_enq_disconnect(pmd->cc, "Missing interrupt fd", 0);
+		return -1;
+	}
+
+	struct memif_queue *mq;
+
+	/* check if we have enough queues */
+	if (ar->flags & MEMIF_MSG_ADD_RING_FLAG_S2M) {
+		if (ar->index >= pmd->cfg.num_s2m_rings) {
+			memif_msg_enq_disconnect(pmd->cc, "Invalid ring index",
+						 0);
+			return -1;
+		}
+		pmd->run.num_s2m_rings++;
+	} else {
+		if (ar->index >= pmd->cfg.num_m2s_rings) {
+			memif_msg_enq_disconnect(pmd->cc, "Invalid ring index",
+						 0);
+			return -1;
+		}
+		pmd->run.num_m2s_rings++;
+	}
+
+	mq = (ar->flags & MEMIF_MSG_ADD_RING_FLAG_S2M) ?
+	    &pmd->rx_queues[ar->index] : &pmd->tx_queues[ar->index];
+
+	mq->intr_handle.fd = fd;
+	mq->log2_ring_size = ar->log2_ring_size;
+	mq->region = ar->region;
+	mq->offset = ar->offset;
+
+	return 0;
+}
+
+static int
+memif_msg_receive_connect(struct pmd_internals *pmd, memif_msg_t * msg)
+{
+	memif_msg_connect_t *c = &msg->connect;
+	int ret;
+
+	ret = memif_connect(pmd);
+	if (ret < 0)
+		return ret;
+
+	strncpy(pmd->remote_if_name, (char *)c->if_name,
+		strlen((char *)c->if_name));
+	MIF_LOG(INFO, "%s: Remote interface %s connected.",
+		rte_vdev_device_name(pmd->vdev), pmd->remote_if_name);
+
+	return 0;
+}
+
+static int
+memif_msg_receive_connected(struct pmd_internals *pmd, memif_msg_t * msg)
+{
+	memif_msg_connected_t *c = &msg->connected;
+	int ret;
+
+	ret = memif_connect(pmd);
+	if (ret < 0)
+		return ret;
+
+	strncpy(pmd->remote_if_name, (char *)c->if_name,
+		strlen((char *)c->if_name));
+	MIF_LOG(INFO, "%s: Remote interface %s connected.",
+		rte_vdev_device_name(pmd->vdev), pmd->remote_if_name);
+
+	return 0;
+}
+
+static int
+memif_msg_receive_disconnect(struct pmd_internals *pmd, memif_msg_t * msg)
+{
+	memif_msg_disconnect_t *d = &msg->disconnect;
+
+	memset(pmd->remote_disc_string, 0, sizeof(pmd->remote_disc_string));
+	strncpy(pmd->remote_disc_string, (char *)d->string,
+		strlen((char *)d->string));
+
+	MIF_LOG(INFO, "%s: Disconnect received: %s",
+		rte_vdev_device_name(pmd->vdev), pmd->remote_disc_string);
+
+	memset(pmd->local_disc_string, 0, 96);
+	memif_disconnect(rte_eth_dev_allocated
+			 (rte_vdev_device_name(pmd->vdev)));
+	return 0;
+}
+
+static int memif_msg_enq_ack(struct pmd_internals *pmd)
+{
+	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
+	if (e == NULL)
+		return -1;
+
+	e->msg.type = MEMIF_MSG_TYPE_ACK;
+
+	return 0;
+}
+
+static int memif_msg_enq_init(struct pmd_internals *pmd)
+{
+	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
+	if (e == NULL)
+		return -1;
+
+	memif_msg_init_t *i = &e->msg.init;
+
+	e->msg.type = MEMIF_MSG_TYPE_INIT;
+	i->version = MEMIF_VERSION;
+	i->id = pmd->id;
+	i->mode = MEMIF_INTERFACE_MODE_ETHERNET;
+
+	strncpy((char *)i->name, rte_version(), strlen(rte_version()));
+
+	if (pmd->secret) {
+		strncpy((char *)i->secret, pmd->secret, sizeof(i->secret) - 1);
+	}
+
+	return 0;
+}
+
+static int memif_msg_enq_add_region(struct pmd_internals *pmd, uint8_t idx)
+{
+	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
+	if (e == NULL)
+		return -1;
+
+	memif_msg_add_region_t *ar = &e->msg.add_region;
+	struct memif_region *mr = &pmd->regions[idx];
+
+	e->msg.type = MEMIF_MSG_TYPE_ADD_REGION;
+	e->fd = mr->fd;
+	ar->index = idx;
+	ar->size = mr->region_size;
+
+	return 0;
+}
+
+static int
+memif_msg_enq_add_ring(struct pmd_internals *pmd, uint8_t idx,
+		       memif_ring_type_t type)
+{
+	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
+	if (e == NULL)
+		return -1;
+
+	memif_msg_add_ring_t *ar = &e->msg.add_ring;
+	struct memif_queue *mq;
+
+	mq = (type == MEMIF_RING_S2M) ? &pmd->tx_queues[idx] :
+	    &pmd->rx_queues[idx];
+
+	e->msg.type = MEMIF_MSG_TYPE_ADD_RING;
+	e->fd = mq->intr_handle.fd;
+	ar->index = idx;
+	ar->offset = mq->offset;
+	ar->region = mq->region;
+	ar->log2_ring_size = mq->log2_ring_size;
+	ar->flags = (type == MEMIF_RING_S2M) ? MEMIF_MSG_ADD_RING_FLAG_S2M : 0;
+	ar->private_hdr_size = 0;
+
+	return 0;
+}
+
+static int memif_msg_enq_connect(struct pmd_internals *pmd)
+{
+	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
+	if (e == NULL)
+		return -1;
+
+	memif_msg_connect_t *c = &e->msg.connect;
+	const char *name = rte_vdev_device_name(pmd->vdev);
+
+	e->msg.type = MEMIF_MSG_TYPE_CONNECT;
+	strncpy((char *)c->if_name, name, strlen(name));
+
+	return 0;
+}
+
+static int memif_msg_enq_connected(struct pmd_internals *pmd)
+{
+	struct memif_msg_queue_elt *e = memif_msg_enq(pmd->cc);
+	if (e == NULL)
+		return -1;
+
+	memif_msg_connected_t *c = &e->msg.connected;
+
+	const char *name = rte_vdev_device_name(pmd->vdev);
+
+	e->msg.type = MEMIF_MSG_TYPE_CONNECTED;
+	strncpy((char *)c->if_name, name, strlen(name));
+
+	return 0;
+}
+
+static void
+memif_intr_unregister_handler(struct rte_intr_handle *intr_handle, void *arg)
+{
+	struct memif_msg_queue_elt *elt;
+	struct memif_control_channel *cc = arg;
+	/* close control channel fd */
+	close(intr_handle->fd);
+	/* clear message queue */
+	while ((elt = TAILQ_FIRST(&cc->msg_queue)) != NULL) {
+		TAILQ_REMOVE(&cc->msg_queue, elt, next);
+		free(elt);
+	}
+	/* free control channel */
+	rte_free(cc);
+}
+
+void memif_disconnect(struct rte_eth_dev *dev)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+	struct memif_msg_queue_elt *elt;
+	int i;
+	int ret;
+
+	if (pmd->cc != NULL) {
+		/* Clear control message queue (except disconnect message if any). */
+		while ((elt = TAILQ_FIRST(&pmd->cc->msg_queue)) != NULL) {
+			if (elt->msg.type != MEMIF_MSG_TYPE_DISCONNECT) {
+				TAILQ_REMOVE(&pmd->cc->msg_queue, elt, next);
+				free(elt);
+			}
+		}
+		/* send disconnect message (if there is any in queue) */
+		memif_msg_send_from_queue(pmd->cc);
+
+		/* at this point, there should be no more messages in queue */
+		if (TAILQ_FIRST(&pmd->cc->msg_queue) != NULL) {
+			MIF_LOG(WARNING,
+				"%s: Unexpected message(s) in message queue.",
+				rte_vdev_device_name(pmd->vdev));
+		}
+
+		if (pmd->cc->intr_handle.fd > 0) {
+			ret =
+			    rte_intr_callback_unregister(&pmd->cc->intr_handle,
+							 memif_intr_handler,
+							 pmd->cc);
+			/*
+			 * If callback is active (disconnecting based on
+			 * received control message).
+			 */
+			if (ret == -EAGAIN) {
+				ret =
+				    rte_intr_callback_unregister_pending(&pmd->
+									 cc->
+									 intr_handle,
+									 memif_intr_handler,
+									 pmd->
+									 cc,
+									 memif_intr_unregister_handler);
+			} else if (ret > 0) {
+				close(pmd->cc->intr_handle.fd);
+				rte_free(pmd->cc);
+			}
+			if (ret <= 0)
+				MIF_LOG(WARNING,
+					"%s: Failed to unregister control channel callback.",
+					rte_vdev_device_name(pmd->vdev));
+		}
+	}
+
+	/* unconfig interrupts */
+	struct memif_queue *mq;
+	for (i = 0; i < pmd->cfg.num_s2m_rings; i++) {
+		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
+		    &pmd->tx_queues[i] : &pmd->rx_queues[i];
+		if (mq->intr_handle.fd > 0) {
+			rte_intr_disable(&mq->intr_handle);
+			close(mq->intr_handle.fd);
+			mq->intr_handle.fd = -1;
+		}
+		mq->ring = NULL;
+	}
+	for (i = 0; i < pmd->cfg.num_m2s_rings; i++) {
+		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
+		    &pmd->rx_queues[i] : &pmd->tx_queues[i];
+		if (mq->intr_handle.fd > 0) {
+			rte_intr_disable(&mq->intr_handle);
+			close(mq->intr_handle.fd);
+			mq->intr_handle.fd = -1;
+		}
+		mq->ring = NULL;
+	}
+
+	memif_free_regions(pmd);
+
+	dev->data->dev_link.link_status = ETH_LINK_DOWN;
+	pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTING;
+	pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTED;
+	MIF_LOG(DEBUG, "%s: Disconnected.", rte_vdev_device_name(pmd->vdev));
+}
+
+static int memif_msg_receive(struct memif_control_channel *cc)
+{
+	char ctl[CMSG_SPACE(sizeof(int)) +
+		 CMSG_SPACE(sizeof(struct ucred))] = { 0 };
+	struct msghdr mh = { 0 };
+	struct iovec iov[1];
+	memif_msg_t msg = { 0 };
+	ssize_t size;
+	int ret = 0;
+	struct ucred *cr __rte_unused;
+	cr = 0;
+	struct cmsghdr *cmsg;
+	int afd = -1;
+	int i;
+
+	iov[0].iov_base = (void *)&msg;
+	iov[0].iov_len = sizeof(memif_msg_t);
+	mh.msg_iov = iov;
+	mh.msg_iovlen = 1;
+	mh.msg_control = ctl;
+	mh.msg_controllen = sizeof(ctl);
+
+	size = recvmsg(cc->intr_handle.fd, &mh, 0);
+	if (size != sizeof(memif_msg_t)) {
+		MIF_LOG(DEBUG, "Invalid message size.");
+		memif_msg_enq_disconnect(cc, "Invalid message size", 0);
+		return -1;
+	}
+	MIF_LOG(DEBUG, "Received msg type: %u.", msg.type);
+
+	cmsg = CMSG_FIRSTHDR(&mh);
+	while (cmsg) {
+		if (cmsg->cmsg_level == SOL_SOCKET) {
+			if (cmsg->cmsg_type == SCM_CREDENTIALS) {
+				cr = (struct ucred *)CMSG_DATA(cmsg);
+			} else if (cmsg->cmsg_type == SCM_RIGHTS) {
+				afd = *(int *)CMSG_DATA(cmsg);
+			}
+		}
+		cmsg = CMSG_NXTHDR(&mh, cmsg);
+	}
+
+	if ((cc->pmd == NULL) && msg.type != MEMIF_MSG_TYPE_INIT) {
+		MIF_LOG(DEBUG, "Unexpected message.");
+		memif_msg_enq_disconnect(cc, "Unexpected message", 0);
+		return -1;
+	}
+
+	/* get device from hash data */
+	switch (msg.type) {
+	case MEMIF_MSG_TYPE_ACK:
+		break;
+	case MEMIF_MSG_TYPE_HELLO:
+		ret = memif_msg_receive_hello(cc->pmd, &msg);
+		if (ret < 0)
+			goto exit;
+		ret = memif_init_regions_and_queues(cc->pmd);
+		if (ret < 0)
+			goto exit;
+		ret = memif_msg_enq_init(cc->pmd);
+		if (ret < 0)
+			goto exit;
+		for (i = 0; i < cc->pmd->regions_num; i++) {
+			ret = memif_msg_enq_add_region(cc->pmd, i);
+			if (ret < 0)
+				goto exit;
+		}
+		for (i = 0; i < cc->pmd->run.num_s2m_rings; i++) {
+			ret = memif_msg_enq_add_ring(cc->pmd, i,
+						     MEMIF_RING_S2M);
+			if (ret < 0)
+				goto exit;
+		}
+		for (i = 0; i < cc->pmd->run.num_m2s_rings; i++) {
+			ret = memif_msg_enq_add_ring(cc->pmd, i,
+						     MEMIF_RING_M2S);
+			if (ret < 0)
+				goto exit;
+		}
+		ret = memif_msg_enq_connect(cc->pmd);
+		if (ret < 0)
+			goto exit;
+		break;
+	case MEMIF_MSG_TYPE_INIT:
+		ret = memif_msg_receive_init(cc, &msg);
+		if (ret < 0)
+			goto exit;
+		ret = memif_msg_enq_ack(cc->pmd);
+		if (ret < 0)
+			goto exit;
+		break;
+	case MEMIF_MSG_TYPE_ADD_REGION:
+		ret = memif_msg_receive_add_region(cc->pmd, &msg, afd);
+		if (ret < 0)
+			goto exit;
+		ret = memif_msg_enq_ack(cc->pmd);
+		if (ret < 0)
+			goto exit;
+		break;
+	case MEMIF_MSG_TYPE_ADD_RING:
+		ret = memif_msg_receive_add_ring(cc->pmd, &msg, afd);
+		if (ret < 0)
+			goto exit;
+		ret = memif_msg_enq_ack(cc->pmd);
+		if (ret < 0)
+			goto exit;
+		break;
+	case MEMIF_MSG_TYPE_CONNECT:
+		ret = memif_msg_receive_connect(cc->pmd, &msg);
+		if (ret < 0)
+			goto exit;
+		ret = memif_msg_enq_connected(cc->pmd);
+		if (ret < 0)
+			goto exit;
+		break;
+	case MEMIF_MSG_TYPE_CONNECTED:
+		ret = memif_msg_receive_connected(cc->pmd, &msg);
+		break;
+	case MEMIF_MSG_TYPE_DISCONNECT:
+		ret = memif_msg_receive_disconnect(cc->pmd, &msg);
+		if (ret < 0)
+			goto exit;
+		break;
+	default:
+		memif_msg_enq_disconnect(cc, "Unknown message type", 0);
+		ret = -1;
+		goto exit;
+	}
+
+ exit:
+	return ret;
+}
+
+static void memif_intr_handler(void *arg)
+{
+	struct memif_control_channel *cc = arg;
+	struct rte_eth_dev *dev;
+	int ret;
+
+	ret = memif_msg_receive(cc);
+	/* if driver failed to assign device */
+	if (cc->pmd == NULL) {
+		ret = rte_intr_callback_unregister_pending(&cc->intr_handle,
+							   memif_intr_handler,
+							   cc,
+							   memif_intr_unregister_handler);
+		if (ret < 0)
+			MIF_LOG(WARNING,
+				"Failed to unregister control channel callback.");
+		return;
+	}
+	/* if memif_msg_receive failed */
+	if (ret < 0)
+		goto disconnect;
+
+	ret = memif_msg_send_from_queue(cc);
+	if (ret < 0)
+		goto disconnect;
+
+	return;
+
+ disconnect:
+	dev = rte_eth_dev_allocated(rte_vdev_device_name(cc->pmd->vdev));
+	if (dev == NULL) {
+		MIF_LOG(WARNING, "%s: eth dev not allocated",
+			rte_vdev_device_name(cc->pmd->vdev));
+		return;
+	}
+	memif_disconnect(dev);
+}
+
+static void memif_listener_handler(void *arg)
+{
+	struct memif_socket *socket = arg;
+	int sockfd;
+	int addr_len;
+	struct sockaddr_un client;
+	struct memif_control_channel *cc;
+	int ret;
+
+	addr_len = sizeof(client);
+	sockfd = accept(socket->intr_handle.fd, (struct sockaddr *)&client,
+			(socklen_t *) & addr_len);
+	if (sockfd < 0) {
+		MIF_LOG(ERR,
+			"Failed to accept connection request on socket fd %d",
+			socket->intr_handle.fd);
+		return;
+	}
+
+	MIF_LOG(DEBUG, "%s: Connection request accepted.", socket->filename);
+
+	cc = rte_zmalloc("memif-cc", sizeof(struct memif_control_channel), 0);
+	if (cc == NULL) {
+		MIF_LOG(ERR, "Failed to allocate control channel.");
+		goto error;
+	}
+
+	cc->intr_handle.fd = sockfd;
+	cc->intr_handle.type = RTE_INTR_HANDLE_EXT;
+	cc->socket = socket;
+	cc->pmd = NULL;
+	TAILQ_INIT(&cc->msg_queue);
+
+	ret =
+	    rte_intr_callback_register(&cc->intr_handle, memif_intr_handler,
+				       cc);
+	if (ret < 0) {
+		MIF_LOG(ERR, "Failed to register control channel callback.");
+		goto error;
+	}
+
+	ret = memif_msg_enq_hello(cc);
+	if (ret < 0) {
+		MIF_LOG(ERR, "Failed to enqueue hello message.");
+		goto error;
+	}
+	ret = memif_msg_send_from_queue(cc);
+	if (ret < 0)
+		goto error;
+
+	return;
+
+ error:
+	if (sockfd > 0) {
+		close(sockfd);
+		sockfd = -1;
+	}
+	if (cc != NULL) {
+		rte_free(cc);
+		cc = NULL;
+	}
+}
+
+static inline struct memif_socket *memif_socket_create(struct pmd_internals
+						       *pmd, char *key,
+						       uint8_t listener)
+{
+	struct memif_socket *sock;
+	struct sockaddr_un un;
+	int sockfd;
+	int ret;
+	int on = 1;
+
+	sock = rte_zmalloc("memif-socket", sizeof(struct memif_socket), 0);
+	if (sock == NULL) {
+		MIF_LOG(ERR, "Failed to allocate memory for memif socket");
+		return NULL;
+	}
+
+	sock->listener = listener;
+	rte_memcpy(sock->filename, key, 256);
+	TAILQ_INIT(&sock->pmd_queue);
+
+	if (listener != 0) {
+		sockfd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
+		if (sockfd < 0)
+			goto error;;
+
+		un.sun_family = AF_UNIX;
+		strncpy((char *)un.sun_path, (char *)sock->filename,
+			sizeof(un.sun_path) - 1);
+
+		ret = setsockopt(sockfd, SOL_SOCKET, SO_PASSCRED, &on,
+				 sizeof(on));
+		if (ret < 0) {
+			goto error;
+		}
+		ret = bind(sockfd, (struct sockaddr *)&un, sizeof(un));
+		if (ret < 0) {
+			goto error;
+		}
+		ret = listen(sockfd, 1);
+		if (ret < 0) {
+			goto error;
+		}
+
+		MIF_LOG(DEBUG, "%s: Memif listener socket %s created.",
+			rte_vdev_device_name(pmd->vdev), sock->filename);
+
+		sock->intr_handle.fd = sockfd;
+		sock->intr_handle.type = RTE_INTR_HANDLE_EXT;
+		ret = rte_intr_callback_register(&sock->intr_handle,
+						 memif_listener_handler, sock);
+		if (ret < 0) {
+			MIF_LOG(ERR, "%s: Failed to register interrupt "
+				"callback for listener socket",
+				rte_vdev_device_name(pmd->vdev));
+			return NULL;
+		}
+	}
+
+	return sock;
+
+ error:
+	MIF_LOG(ERR, "%s: Failed to setup socket %s: %s",
+		rte_vdev_device_name(pmd->vdev), key, strerror(errno));
+	if (sock != NULL)
+		rte_free(sock);
+	return NULL;
+}
+
+static inline struct rte_hash *memif_create_socket_hash(void)
+{
+	struct rte_hash_parameters params = { 0 };
+	params.name = MEMIF_SOCKET_HASH_NAME;
+	params.entries = 256;
+	params.key_len = 256;
+	params.hash_func = rte_jhash;
+	params.hash_func_init_val = 0;
+	return rte_hash_create(&params);
+}
+
+int memif_socket_init(struct rte_eth_dev *dev, const char *socket_filename)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+	struct memif_socket *socket = NULL;
+	struct memif_socket_pmd_list_elt *elt;
+	int ret;
+	char key[256];
+
+	struct rte_hash *hash = rte_hash_find_existing(MEMIF_SOCKET_HASH_NAME);
+	if (hash == NULL) {
+		hash = memif_create_socket_hash();
+		if (hash == NULL) {
+			MIF_LOG(ERR, "Failed to create memif socket hash.");
+			return -1;
+		}
+	}
+
+	memset(key, 0, 256);
+	rte_memcpy(key, socket_filename, strlen(socket_filename));
+	ret = rte_hash_lookup_data(hash, key, (void **)&socket);
+	if (ret < 0) {
+		socket = memif_socket_create(pmd, key,
+					     (pmd->role ==
+					      MEMIF_ROLE_SLAVE) ? 0 : 1);
+		if (socket == NULL) {
+			return -1;
+		}
+		ret = rte_hash_add_key_data(hash, key, socket);
+		if (ret < 0) {
+			MIF_LOG(ERR, "Failed to add socket to socket hash.");
+			return ret;
+		}
+	}
+	pmd->socket_filename = socket->filename;
+
+	if ((socket->listener != 0) && (pmd->role == MEMIF_ROLE_SLAVE)) {
+		MIF_LOG(ERR, "Socket is a listener.");
+		return -1;
+	} else if ((socket->listener == 0) && (pmd->role == MEMIF_ROLE_MASTER)) {
+		MIF_LOG(ERR, "Socket is not a listener.");
+		return -1;
+	}
+
+	TAILQ_FOREACH(elt, &socket->pmd_queue, next) {
+		if (elt->pmd->id == pmd->id) {
+			MIF_LOG(ERR, "Memif device with id %d already "
+				"exists on socket %s",
+				pmd->id, socket->filename);
+			return -1;
+		}
+	}
+
+	elt =
+	    rte_malloc("pmd-queue", sizeof(struct memif_socket_pmd_list_elt),
+		       0);
+	if (elt == NULL) {
+		MIF_LOG(ERR, "%s: Failed to add device to socket device list.",
+			rte_vdev_device_name(pmd->vdev));
+		return -1;
+	}
+	elt->pmd = pmd;
+	TAILQ_INSERT_TAIL(&socket->pmd_queue, elt, next);
+
+	return 0;
+}
+
+void memif_socket_remove_device(struct pmd_internals *pmd)
+{
+	struct memif_socket *socket = NULL;
+	struct memif_socket_pmd_list_elt *elt, *next;
+
+	struct rte_hash *hash = rte_hash_find_existing(MEMIF_SOCKET_HASH_NAME);
+	if (hash == NULL) {
+		return;
+	}
+
+	if (rte_hash_lookup_data(hash, pmd->socket_filename, (void **)&socket) <
+	    0)
+		return;
+
+	for (elt = TAILQ_FIRST(&socket->pmd_queue); elt != NULL; elt = next) {
+		next = TAILQ_NEXT(elt, next);
+		if (elt->pmd == pmd) {
+			TAILQ_REMOVE(&socket->pmd_queue, elt, next);
+			free(elt);
+			pmd->socket_filename = NULL;
+		}
+	}
+
+	/* remove socket, if this was the last device using it */
+	if (TAILQ_EMPTY(&socket->pmd_queue)) {
+		rte_hash_del_key(hash, socket->filename);
+		if (socket->listener) {
+			/* remove listener socket file,
+			 * so we can create new one later.
+			 */
+			remove(socket->filename);
+		}
+		rte_free(socket);
+	}
+}
+
+int memif_connect_master(struct rte_eth_dev *dev)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+	if ((pmd->rx_queues == NULL) || (pmd->tx_queues == NULL) ||
+	    (pmd->socket_filename == NULL)) {
+		MIF_LOG(ERR, "%s: Device not configured!",
+			rte_vdev_device_name(pmd->vdev));
+		return -1;
+	}
+	memset(pmd->local_disc_string, 0, 96);
+	memset(pmd->remote_disc_string, 0, 96);
+	pmd->flags &= ~ETH_MEMIF_FLAG_DISABLED;
+	return 0;
+}
+
+int memif_connect_slave(struct rte_eth_dev *dev)
+{
+	int sockfd;
+	int ret;
+	struct sockaddr_un sun;
+	struct pmd_internals *pmd = dev->data->dev_private;
+
+	if ((pmd->rx_queues == NULL) || (pmd->tx_queues == NULL) ||
+	    (pmd->socket_filename == NULL)) {
+		MIF_LOG(ERR, "%s: Device not configured!",
+			rte_vdev_device_name(pmd->vdev));
+		return -1;
+	}
+
+	memset(pmd->local_disc_string, 0, 96);
+	memset(pmd->remote_disc_string, 0, 96);
+	pmd->flags &= ~ETH_MEMIF_FLAG_DISABLED;
+
+	sockfd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
+	if (sockfd < 0) {
+		MIF_LOG(ERR, "%s: Failed to open socket.",
+			rte_vdev_device_name(pmd->vdev));
+		return -1;
+	}
+
+	sun.sun_family = AF_UNIX;
+
+	strncpy(sun.sun_path, pmd->socket_filename, sizeof(sun.sun_path) - 1);
+
+	ret = connect(sockfd, (struct sockaddr *)&sun,
+		      sizeof(struct sockaddr_un));
+	if (ret < 0) {
+		MIF_LOG(ERR, "%s: Failed to connect socket: %s.",
+			rte_vdev_device_name(pmd->vdev), pmd->socket_filename);
+		goto error;
+	}
+
+	MIF_LOG(DEBUG, "%s: Memif socket: %s connected.",
+		rte_vdev_device_name(pmd->vdev), pmd->socket_filename);
+
+	pmd->cc = rte_zmalloc("memif-cc",
+			      sizeof(struct memif_control_channel), 0);
+	if (pmd->cc == NULL) {
+		MIF_LOG(ERR, "%s: Failed to allocate control channel.",
+			rte_vdev_device_name(pmd->vdev));
+		goto error;
+	}
+
+	pmd->cc->intr_handle.fd = sockfd;
+	pmd->cc->intr_handle.type = RTE_INTR_HANDLE_EXT;
+	pmd->cc->socket = NULL;
+	pmd->cc->pmd = pmd;
+	TAILQ_INIT(&pmd->cc->msg_queue);
+
+	ret = rte_intr_callback_register(&pmd->cc->intr_handle,
+					 memif_intr_handler, pmd->cc);
+	if (ret < 0) {
+		MIF_LOG(ERR, "%s: Failed to register interrupt callback "
+			"for controll fd", rte_vdev_device_name(pmd->vdev));
+		goto error;
+	}
+
+	return 0;
+
+ error:
+	if (sockfd > 0) {
+		close(sockfd);
+		sockfd = -1;
+	}
+	if (pmd->cc != NULL) {
+		rte_free(pmd->cc);
+		pmd->cc = NULL;
+	}
+	return -1;
+}
diff --git a/drivers/net/memif/memif_socket.h b/drivers/net/memif/memif_socket.h
new file mode 100644
index 000000000..f9136dbe5
--- /dev/null
+++ b/drivers/net/memif/memif_socket.h
@@ -0,0 +1,57 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
+ */
+
+#ifndef _MEMIF_SOCKET_H_
+#define _MEMIF_SOCKET_H_
+
+#include <sys/queue.h>
+
+/*
+ * Remove device from socket device list. If no device is left on the socket,
+ * remove the socket as well.
+ */
+void memif_socket_remove_device(struct pmd_internals *pmd);
+
+void memif_msg_enq_disconnect(struct memif_control_channel *cc,
+			      const char *reason, int err_code);
+
+int memif_socket_init(struct rte_eth_dev *dev, const char *socket_filename);
+
+void memif_disconnect(struct rte_eth_dev *dev);
+
+/* Allow master to receive connection requests. */
+int memif_connect_master(struct rte_eth_dev *dev);
+
+/* Send connection request. */
+int memif_connect_slave(struct rte_eth_dev *dev);
+
+struct memif_socket_pmd_list_elt {
+	TAILQ_ENTRY(memif_socket_pmd_list_elt) next;
+	struct pmd_internals *pmd;
+};
+
+#define MEMIF_SOCKET_HASH_NAME			"memif-sh"
+struct memif_socket {
+	struct rte_intr_handle intr_handle;
+	uint8_t listener;
+	char filename[256];
+
+	 TAILQ_HEAD(, memif_socket_pmd_list_elt) pmd_queue;
+};
+
+/* Control mesage queue. */
+struct memif_msg_queue_elt {
+	TAILQ_ENTRY(memif_msg_queue_elt) next;
+	memif_msg_t msg;
+	int fd;
+};
+
+struct memif_control_channel {
+	struct rte_intr_handle intr_handle;
+	 TAILQ_HEAD(, memif_msg_queue_elt) msg_queue;
+	struct memif_socket *socket;
+	struct pmd_internals *pmd;
+};
+
+#endif				/* MEMIF_SOCKET_H */
diff --git a/drivers/net/memif/meson.build b/drivers/net/memif/meson.build
new file mode 100644
index 000000000..ea18394fd
--- /dev/null
+++ b/drivers/net/memif/meson.build
@@ -0,0 +1,8 @@ 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright 2018 Cisco Systems, Inc.  All rights reserved.
+
+if host_machine.system() != 'linux'
+        build = false
+endif
+sources = files('rte_eth_memif.c',
+		'memif_socket.c')
diff --git a/drivers/net/memif/rte_eth_memif.c b/drivers/net/memif/rte_eth_memif.c
new file mode 100644
index 000000000..7988010c4
--- /dev/null
+++ b/drivers/net/memif/rte_eth_memif.c
@@ -0,0 +1,1172 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
+ */
+
+#include <stdlib.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <linux/if_ether.h>
+#include <errno.h>
+#include <sys/eventfd.h>
+
+#include <rte_version.h>
+#include <rte_mbuf.h>
+#include <rte_ether.h>
+#include <rte_ethdev_driver.h>
+#include <rte_ethdev_vdev.h>
+#include <rte_malloc.h>
+#include <rte_kvargs.h>
+#include <rte_bus_vdev.h>
+
+#include <rte_eth_memif.h>
+#include <memif_socket.h>
+
+#define ETH_MEMIF_ID_ARG		"id"
+#define ETH_MEMIF_ROLE_ARG		"role"
+#define ETH_MEMIF_BUFFER_SIZE_ARG	"bsize"
+#define ETH_MEMIF_RING_SIZE_ARG		"rsize"
+#define ETH_MEMIF_NRXQ_ARG		"nrxq"
+#define ETH_MEMIF_NTXQ_ARG		"ntxq"
+#define ETH_MEMIF_SOCKET_ARG		"socket"
+#define ETH_MEMIF_MAC_ARG		"mac"
+#define ETH_MEMIF_ZC_ARG		"zero-copy"
+#define ETH_MEMIF_SECRET_ARG		"secret"
+
+static const char *valid_arguments[] = {
+	ETH_MEMIF_ID_ARG,
+	ETH_MEMIF_ROLE_ARG,
+	ETH_MEMIF_BUFFER_SIZE_ARG,
+	ETH_MEMIF_RING_SIZE_ARG,
+	ETH_MEMIF_NRXQ_ARG,
+	ETH_MEMIF_NTXQ_ARG,
+	ETH_MEMIF_SOCKET_ARG,
+	ETH_MEMIF_MAC_ARG,
+	ETH_MEMIF_ZC_ARG,
+	ETH_MEMIF_SECRET_ARG,
+	NULL
+};
+
+static struct rte_vdev_driver pmd_memif_drv;
+
+const char *memif_version(void)
+{
+#define STR_HELP(s)	#s
+#define STR(s)		STR_HELP(s)
+	return ("memif-" STR(MEMIF_VERSION_MAJOR) "." STR(MEMIF_VERSION_MINOR));
+#undef STR
+#undef STR_HELP
+}
+
+static void
+memif_dev_info(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+
+	dev_info->if_index = pmd->if_index;
+	dev_info->max_mac_addrs = 1;
+	dev_info->max_rx_pktlen = (uint32_t) ETH_FRAME_LEN;
+	dev_info->max_rx_queues = (pmd->role == MEMIF_ROLE_SLAVE) ?
+	    pmd->cfg.num_m2s_rings : pmd->cfg.num_s2m_rings;
+	dev_info->max_tx_queues = (pmd->role == MEMIF_ROLE_SLAVE) ?
+	    pmd->cfg.num_s2m_rings : pmd->cfg.num_m2s_rings;
+	dev_info->min_rx_bufsize = 0;
+}
+
+static inline memif_ring_t *memif_get_ring(struct pmd_internals *pmd,
+					   memif_ring_type_t type,
+					   uint16_t ring_num)
+{
+	/* rings only in region 0 */
+	void *p = pmd->regions[0].addr;
+	int ring_size = sizeof(memif_ring_t) + sizeof(memif_desc_t) *
+	    (1 << pmd->run.log2_ring_size);
+	p += (ring_num + type * pmd->run.num_s2m_rings) * ring_size;
+
+	return (memif_ring_t *) p;
+}
+
+static inline void *memif_get_buffer(struct pmd_internals *pmd,
+				     memif_desc_t * d)
+{
+	return (pmd->regions[d->region].addr + d->offset);
+}
+
+static uint16_t
+eth_memif_rx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
+{
+	struct memif_queue *mq = queue;
+	struct pmd_internals *pmd = mq->pmd;
+	if (unlikely((pmd->flags & ETH_MEMIF_FLAG_CONNECTED) == 0))
+		return 0;
+	memif_ring_t *ring = mq->ring;
+	if (unlikely(ring == NULL))
+		return 0;
+	uint16_t cur_slot, last_slot, n_slots, ring_size, mask, s0;
+	uint16_t n_rx_pkts = 0;
+	uint16_t mbuf_size = rte_pktmbuf_data_room_size(mq->mempool) -
+	    RTE_PKTMBUF_HEADROOM;
+	uint16_t src_len, src_off, dst_len, dst_off, cp_len;
+	memif_ring_type_t type = mq->type;
+	memif_desc_t *d0;
+	struct rte_mbuf *mbuf;
+	struct rte_mbuf *mbuf_head = NULL;
+
+	/* consume interrupt */
+	if ((ring->flags & MEMIF_RING_FLAG_MASK_INT) == 0) {
+		uint64_t b;
+		ssize_t size __rte_unused;
+		size = read(mq->intr_handle.fd, &b, sizeof(b));
+	}
+
+	ring_size = 1 << mq->log2_ring_size;
+	mask = ring_size - 1;
+
+	cur_slot = (type == MEMIF_RING_S2M) ? mq->last_head : mq->last_tail;
+	last_slot = (type == MEMIF_RING_S2M) ? ring->head : ring->tail;
+	if (cur_slot == last_slot)
+		goto refill;
+	n_slots = last_slot - cur_slot;
+
+	while (n_slots && n_rx_pkts < nb_pkts) {
+		mbuf_head = rte_pktmbuf_alloc(mq->mempool);
+		if (unlikely(mbuf_head == NULL))
+			goto no_free_bufs;
+		mbuf = mbuf_head;
+		mbuf->port = mq->in_port;
+
+ next_slot:
+		s0 = cur_slot & mask;
+		d0 = &ring->desc[s0];
+
+		src_len = d0->length;
+		dst_off = 0;
+		src_off = 0;
+
+		do {
+			dst_len = mbuf_size - dst_off;
+			if (dst_len == 0) {
+				dst_off = 0;
+				dst_len = mbuf_size + RTE_PKTMBUF_HEADROOM;
+
+				mbuf = rte_pktmbuf_alloc(mq->mempool);
+				if (unlikely(mbuf == NULL))
+					goto no_free_bufs;
+				mbuf->port = mq->in_port;
+				rte_pktmbuf_chain(mbuf_head, mbuf);
+			}
+			cp_len = memif_min(dst_len, src_len);
+
+			rte_pktmbuf_pkt_len(mbuf) =
+			    rte_pktmbuf_data_len(mbuf) += cp_len;
+
+			memcpy(rte_pktmbuf_mtod_offset(mbuf, void *, dst_off),
+			       memif_get_buffer(pmd, d0) + src_off, cp_len);
+
+			mq->n_bytes += cp_len;
+			src_off += cp_len;
+			dst_off += cp_len;
+			src_len -= cp_len;
+		} while (src_len);
+
+		cur_slot++;
+		n_slots--;
+		if (d0->flags & MEMIF_DESC_FLAG_NEXT) {
+			goto next_slot;
+		}
+
+		*bufs++ = mbuf_head;
+		n_rx_pkts++;
+
+	}
+
+ no_free_bufs:
+	if (type == MEMIF_RING_S2M) {
+		rte_mb();
+		ring->tail = mq->last_head = cur_slot;
+	} else {
+		mq->last_tail = cur_slot;
+	}
+
+ refill:
+	if (type == MEMIF_RING_M2S) {
+		uint16_t head = ring->head;
+		n_slots = ring_size - head + mq->last_tail;
+
+		while (n_slots--) {
+			s0 = head++ & mask;
+			d0 = &ring->desc[s0];
+			d0->length = pmd->run.buffer_size;
+		}
+		rte_mb();
+		ring->head = head;
+	}
+
+	mq->n_pkts += n_rx_pkts;
+	return n_rx_pkts;
+}
+
+static uint16_t
+eth_memif_tx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
+{
+	struct memif_queue *mq = queue;
+	struct pmd_internals *pmd = mq->pmd;
+	if (unlikely((pmd->flags & ETH_MEMIF_FLAG_CONNECTED) == 0))
+		return 0;
+	memif_ring_t *ring = mq->ring;
+	if (unlikely(ring == NULL))
+		return 0;
+	uint16_t slot, saved_slot, n_free, ring_size, mask, n_tx_pkts = 0;
+	uint16_t src_len, src_off, dst_len, dst_off, cp_len;
+	memif_ring_type_t type = mq->type;
+	memif_desc_t *d0;
+	struct rte_mbuf *mbuf;
+	struct rte_mbuf *mbuf_head;
+
+	ring_size = 1 << mq->log2_ring_size;
+	mask = ring_size - 1;
+
+	n_free = ring->tail - mq->last_tail;
+	mq->last_tail += n_free;
+	slot = (type == MEMIF_RING_S2M) ? ring->head : ring->tail;
+
+	if (type == MEMIF_RING_S2M)
+		n_free = ring_size - ring->head + mq->last_tail;
+	else
+		n_free = ring->head - ring->tail;
+
+	while (n_free && n_tx_pkts < nb_pkts) {
+		mbuf_head = *bufs++;
+		mbuf = mbuf_head;
+
+		saved_slot = slot;
+		d0 = &ring->desc[slot & mask];
+		dst_off = 0;
+		dst_len =
+		    (type ==
+		     MEMIF_RING_S2M) ? pmd->run.buffer_size : d0->length;
+
+ next_in_chain:
+		src_off = 0;
+		src_len = rte_pktmbuf_data_len(mbuf);
+
+		while (src_len) {
+			if (dst_len == 0) {
+				if (n_free) {
+					slot++;
+					n_free--;
+					d0->flags |= MEMIF_DESC_FLAG_NEXT;
+					d0 = &ring->desc[slot & mask];
+					dst_off = 0;
+					dst_len = (type == MEMIF_RING_S2M) ?
+					    pmd->run.buffer_size : d0->length;
+					d0->flags = 0;
+				} else {
+					slot = saved_slot;
+					goto no_free_slots;
+				}
+			}
+			cp_len = memif_min(dst_len, src_len);
+
+			memcpy(memif_get_buffer(pmd, d0) + dst_off,
+			       rte_pktmbuf_mtod_offset(mbuf, void *, src_off),
+			       cp_len);
+
+			mq->n_bytes += cp_len;
+			src_off += cp_len;
+			dst_off += cp_len;
+			src_len -= cp_len;
+			dst_len -= cp_len;
+
+			d0->length = dst_off;
+		}
+
+		if (rte_pktmbuf_is_contiguous(mbuf) == 0) {
+			mbuf = mbuf->next;
+			goto next_in_chain;
+		}
+
+		n_tx_pkts++;
+		slot++;
+		n_free--;
+		rte_pktmbuf_free(mbuf_head);
+	}
+
+ no_free_slots:
+	rte_mb();
+	if (type == MEMIF_RING_S2M)
+		ring->head = slot;
+	else
+		ring->tail = slot;
+
+	if ((ring->flags & MEMIF_RING_FLAG_MASK_INT) == 0) {
+		uint64_t a = 1;
+		ssize_t size = write(mq->intr_handle.fd, &a, sizeof(a));
+		if (unlikely(size < 0)) {
+			MIF_LOG(WARNING,
+				"%s: Failed to send interrupt on qid %ld: %s",
+				rte_vdev_device_name(pmd->vdev),
+				mq - pmd->tx_queues, strerror(errno));
+		}
+	}
+
+	mq->n_err += nb_pkts - n_tx_pkts;
+	mq->n_pkts += n_tx_pkts;
+	return n_tx_pkts;
+}
+
+void memif_free_regions(struct pmd_internals *pmd)
+{
+	int i;
+	struct memif_region *r;
+
+	for (i = 0; i < pmd->regions_num; i++) {
+		r = pmd->regions + i;
+		if (r == NULL)
+			return;
+		if (r->addr == NULL)
+			return;
+		munmap(r->addr, r->region_size);
+		if (r->fd > 0) {
+			close(r->fd);
+			r->fd = -1;
+		}
+	}
+	rte_free(pmd->regions);
+}
+
+static int memif_alloc_regions(struct pmd_internals *pmd, uint8_t brn)
+{
+	struct memif_region *r;
+	char shm_name[32];
+	int i;
+	int ret = 0;
+
+	r = rte_zmalloc("memif_region", sizeof(struct memif_region) * (brn + 1),
+			0);
+	if (r == NULL) {
+		MIF_LOG(ERR, "%s: Failed to allocate regions.",
+			rte_vdev_device_name(pmd->vdev));
+		return -ENOMEM;
+	}
+
+	pmd->regions = r;
+	pmd->regions_num = brn + 1;
+
+	/*
+	 * Create shm for every region. Region 0 is reserved for descriptors.
+	 * Other regions contain buffers.
+	 */
+	for (i = 0; i < (brn + 1); i++) {
+		r = &pmd->regions[i];
+
+		r->buffer_offset = (i == 0) ? (pmd->run.num_s2m_rings +
+					       pmd->run.num_m2s_rings) *
+		    (sizeof(memif_ring_t) +
+		     sizeof(memif_desc_t) * (1 << pmd->run.log2_ring_size)) : 0;
+		r->region_size = (i == 0) ? r->buffer_offset :
+		    (uint32_t) (pmd->run.buffer_size *
+				(1 << pmd->run.log2_ring_size) *
+				(pmd->run.num_s2m_rings +
+				 pmd->run.num_m2s_rings));
+
+		memset(shm_name, 0, sizeof(char) * 32);
+		sprintf(shm_name, "memif region %d", i);
+
+		r->fd = memfd_create(shm_name, MFD_ALLOW_SEALING);
+		if (r->fd < 0) {
+			MIF_LOG(ERR, "%s: Failed to create shm file: %s.",
+				rte_vdev_device_name(pmd->vdev),
+				strerror(errno));
+			return -1;
+		}
+
+		ret = fcntl(r->fd, F_ADD_SEALS, F_SEAL_SHRINK);
+		if (ret < 0) {
+			MIF_LOG(ERR, "%s: Failed to add seals to shm file: %s.",
+				rte_vdev_device_name(pmd->vdev),
+				strerror(errno));
+			return -1;
+		}
+
+		ret = ftruncate(r->fd, r->region_size);
+		if (ret < 0) {
+			MIF_LOG(ERR, "%s: Failed to truncate shm file: %s.",
+				rte_vdev_device_name(pmd->vdev),
+				strerror(errno));
+			return -1;
+		}
+
+		r->addr = mmap(NULL, r->region_size, PROT_READ |
+			       PROT_WRITE, MAP_SHARED, r->fd, 0);
+		if (r->addr == NULL) {
+			MIF_LOG(ERR, "%s: Failed to mmap shm region: %s.",
+				rte_vdev_device_name(pmd->vdev),
+				strerror(errno));
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static void memif_init_rings(struct pmd_internals *pmd)
+{
+	memif_ring_t *ring;
+	int i, j;
+
+	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
+		ring = memif_get_ring(pmd, MEMIF_RING_S2M, i);
+		ring->head = ring->tail = 0;
+		ring->cookie = MEMIF_COOKIE;
+		ring->flags = 0;
+		for (j = 0; j < (1 << pmd->run.log2_ring_size); j++) {
+			uint16_t slot = i * (1 << pmd->run.log2_ring_size) + j;
+			ring->desc[j].region = 1;
+			ring->desc[j].offset = pmd->regions[1].buffer_offset +
+			    (uint32_t) (slot * pmd->run.buffer_size);
+			ring->desc[j].length = pmd->run.buffer_size;
+		}
+	}
+
+	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
+		ring = memif_get_ring(pmd, MEMIF_RING_M2S, i);
+		ring->head = ring->tail = 0;
+		ring->cookie = MEMIF_COOKIE;
+		ring->flags = 0;
+		for (j = 0; j < (1 << pmd->run.log2_ring_size); j++) {
+			uint16_t slot = (i + pmd->run.num_s2m_rings) *
+			    (1 << pmd->run.log2_ring_size) + j;
+			ring->desc[j].region = 1;
+			ring->desc[j].offset = pmd->regions[1].buffer_offset +
+			    (uint32_t) (slot * pmd->run.buffer_size);
+			ring->desc[j].length = pmd->run.buffer_size;
+		}
+	}
+}
+
+static void memif_init_queues(struct pmd_internals *pmd)
+{
+	struct memif_queue *mq;
+	int i;
+
+	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
+		mq = &pmd->tx_queues[i];
+		mq->ring = memif_get_ring(pmd, MEMIF_RING_S2M, i);
+		mq->log2_ring_size = pmd->run.log2_ring_size;
+		/* queues located only in region 0 */
+		mq->region = 0;
+		mq->offset = (void *)mq->ring - (void *)pmd->regions[0].addr;
+		mq->last_head = mq->last_tail = 0;
+		mq->intr_handle.fd = eventfd(0, EFD_NONBLOCK);
+		if (mq->intr_handle.fd < 0) {
+			MIF_LOG(WARNING,
+				"%s: Failed to create eventfd for tx queue %d: %s.",
+				rte_vdev_device_name(pmd->vdev), i,
+				strerror(errno));
+		}
+	}
+
+	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
+		mq = &pmd->rx_queues[i];
+		mq->ring = memif_get_ring(pmd, MEMIF_RING_M2S, i);
+		mq->log2_ring_size = pmd->run.log2_ring_size;
+		/* queues located only in region 0 */
+		mq->region = 0;
+		mq->offset = (void *)mq->ring - (void *)pmd->regions[0].addr;
+		mq->last_head = mq->last_tail = 0;
+		mq->intr_handle.fd = eventfd(0, EFD_NONBLOCK);
+		if (mq->intr_handle.fd < 0) {
+			MIF_LOG(WARNING,
+				"%s: Failed to create eventfd for rx queue %d: %s.",
+				rte_vdev_device_name(pmd->vdev), i,
+				strerror(errno));
+		}
+	}
+}
+
+int memif_init_regions_and_queues(struct pmd_internals *pmd)
+{
+	int ret;
+
+	ret = memif_alloc_regions(pmd, /* num of buffer regions */ 1);
+	if (ret < 0) {
+		return ret;
+	}
+
+	memif_init_rings(pmd);
+
+	memif_init_queues(pmd);
+
+	return 0;
+}
+
+int memif_connect(struct pmd_internals *pmd)
+{
+	struct rte_eth_dev *eth_dev =
+	    rte_eth_dev_allocated(rte_vdev_device_name(pmd->vdev));
+	struct memif_region *mr;
+	struct memif_queue *mq;
+	int i;
+
+	for (i = 0; i < pmd->regions_num; i++) {
+		mr = pmd->regions + i;
+		if (mr != NULL) {
+			if (mr->addr == NULL) {
+				if (mr->fd < 0)
+					return -1;
+				mr->addr = mmap(NULL, mr->region_size,
+						PROT_READ | PROT_WRITE,
+						MAP_SHARED, mr->fd, 0);
+				if (mr->addr == NULL)
+					return -1;
+			}
+		}
+	}
+
+	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
+		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
+		    &pmd->tx_queues[i] : &pmd->rx_queues[i];
+		mq->ring = pmd->regions[mq->region].addr + mq->offset;
+		if (mq->ring->cookie != MEMIF_COOKIE) {
+			MIF_LOG(ERR, "%s: Wrong cookie",
+				rte_vdev_device_name(pmd->vdev));
+			return -1;
+		}
+		mq->ring->head = mq->ring->tail = mq->last_head =
+		    mq->last_tail = 0;
+		/* polling mode by default */
+		if (pmd->role == MEMIF_ROLE_MASTER) {
+			mq->ring->flags = MEMIF_RING_FLAG_MASK_INT;
+		}
+	}
+	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
+		mq = (pmd->role == MEMIF_ROLE_SLAVE) ?
+		    &pmd->rx_queues[i] : &pmd->tx_queues[i];
+		mq->ring = pmd->regions[mq->region].addr + mq->offset;
+		if (mq->ring->cookie != MEMIF_COOKIE) {
+			MIF_LOG(ERR, "%s: Wrong cookie",
+				rte_vdev_device_name(pmd->vdev));
+			return -1;
+		}
+		mq->ring->head = mq->ring->tail = mq->last_head =
+		    mq->last_tail = 0;
+		/* polling mode by default */
+		if (pmd->role == MEMIF_ROLE_SLAVE) {
+			mq->ring->flags = MEMIF_RING_FLAG_MASK_INT;
+		}
+	}
+
+	pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTING;
+	pmd->flags |= ETH_MEMIF_FLAG_CONNECTED;
+	eth_dev->data->dev_link.link_status = ETH_LINK_UP;
+	MIF_LOG(INFO, "%s: Connected.", rte_vdev_device_name(pmd->vdev));
+	return 0;
+}
+
+static int memif_dev_start(struct rte_eth_dev *dev)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+	int ret = 0;
+
+	switch (pmd->role) {
+	case MEMIF_ROLE_SLAVE:
+		ret = memif_connect_slave(dev);
+		break;
+	case MEMIF_ROLE_MASTER:
+		ret = memif_connect_master(dev);
+		break;
+	default:
+		MIF_LOG(ERR, "%s: Unknown role: %d.",
+			rte_vdev_device_name(pmd->vdev), pmd->role);
+		ret = -1;
+		break;
+	}
+
+	return ret;
+}
+
+static int memif_dev_configure(struct rte_eth_dev *dev __rte_unused)
+{
+	return 0;
+}
+
+static int
+memif_tx_queue_setup(struct rte_eth_dev *dev,
+		     uint16_t qid,
+		     uint16_t nb_tx_desc __rte_unused,
+		     unsigned int socket_id __rte_unused,
+		     const struct rte_eth_txconf *tx_conf __rte_unused)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+	struct memif_queue *mq;
+
+	mq = rte_realloc(pmd->tx_queues, sizeof(struct memif_queue) * (qid + 1),
+			 0);
+	if (mq == NULL) {
+		MIF_LOG(ERR, "%s: Failed to alloc tx queue %u.",
+			rte_vdev_device_name(pmd->vdev), qid);
+		return -ENOMEM;
+	}
+
+	pmd->tx_queues = mq;
+
+	mq->type =
+	    (pmd->role == MEMIF_ROLE_SLAVE) ? MEMIF_RING_S2M : MEMIF_RING_M2S;
+	mq->n_pkts = 0;
+	mq->n_bytes = 0;
+	mq->n_err = 0;
+	mq->intr_handle.fd = -1;
+	mq->intr_handle.type = RTE_INTR_HANDLE_EXT;
+	mq->pmd = pmd;
+	dev->data->tx_queues[qid] = mq;
+
+	return 0;
+}
+
+static int
+memif_rx_queue_setup(struct rte_eth_dev *dev,
+		     uint16_t qid,
+		     uint16_t nb_rx_desc __rte_unused,
+		     unsigned int socket_id __rte_unused,
+		     const struct rte_eth_rxconf *rx_conf __rte_unused,
+		     struct rte_mempool *mb_pool)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+	struct memif_queue *mq;
+
+	mq = rte_realloc(pmd->rx_queues, sizeof(struct memif_queue) * (qid + 1),
+			 0);
+	if (mq == NULL) {
+		MIF_LOG(ERR, "%s: Failed to alloc rx queue %u.",
+			rte_vdev_device_name(pmd->vdev), qid);
+		return -ENOMEM;
+	}
+
+	pmd->rx_queues = mq;
+
+	mq->type =
+	    (pmd->role == MEMIF_ROLE_SLAVE) ? MEMIF_RING_M2S : MEMIF_RING_S2M;
+	mq->n_pkts = 0;
+	mq->n_bytes = 0;
+	mq->n_err = 0;
+	mq->intr_handle.fd = -1;
+	mq->intr_handle.type = RTE_INTR_HANDLE_EXT;
+	mq->mempool = mb_pool;
+	mq->in_port = dev->data->port_id;
+	mq->pmd = pmd;
+	dev->data->rx_queues[qid] = mq;
+
+	return 0;
+}
+
+static int
+memif_link_update(struct rte_eth_dev *dev __rte_unused,
+		  int wait_to_complete __rte_unused)
+{
+	return 0;
+}
+
+static int memif_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *stats)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+	struct memif_queue *mq;
+	int i;
+
+	stats->ipackets = 0;
+	stats->ibytes = 0;
+	stats->opackets = 0;
+	stats->obytes = 0;
+	stats->oerrors = 0;
+
+	uint8_t tmp = (pmd->role == MEMIF_ROLE_SLAVE) ? pmd->run.num_s2m_rings :
+	    pmd->run.num_m2s_rings;
+	uint8_t nq = (tmp < RTE_ETHDEV_QUEUE_STAT_CNTRS) ? tmp :
+	    RTE_ETHDEV_QUEUE_STAT_CNTRS;
+
+	/* RX stats */
+	for (i = 0; i < nq; i++) {
+		mq = &pmd->rx_queues[i];
+		stats->q_ipackets[i] = mq->n_pkts;
+		stats->q_ibytes[i] = mq->n_bytes;
+		stats->ipackets += mq->n_pkts;
+		stats->ibytes += mq->n_bytes;
+	}
+
+	tmp = (pmd->role == MEMIF_ROLE_SLAVE) ? pmd->run.num_m2s_rings :
+	    pmd->run.num_s2m_rings;
+	nq = (tmp < RTE_ETHDEV_QUEUE_STAT_CNTRS) ? tmp :
+	    RTE_ETHDEV_QUEUE_STAT_CNTRS;
+
+	/* TX stats */
+	for (i = 0; i < nq; i++) {
+		mq = &pmd->tx_queues[i];
+		stats->q_opackets[i] = mq->n_pkts;
+		stats->q_obytes[i] = mq->n_bytes;
+		stats->q_errors[i] = mq->n_err;
+		stats->opackets += mq->n_pkts;
+		stats->obytes += mq->n_bytes;
+		stats->oerrors += mq->n_err;
+	}
+	return 0;
+}
+
+static void memif_stats_reset(struct rte_eth_dev *dev)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+	int i;
+	struct memif_queue *mq;
+
+	for (i = 0; i < pmd->run.num_s2m_rings; i++) {
+		mq = (pmd->role == MEMIF_ROLE_SLAVE) ? &pmd->tx_queues[i] :
+		    &pmd->rx_queues[i];
+		mq->n_pkts = 0;
+		mq->n_bytes = 0;
+		mq->n_err = 0;
+	}
+	for (i = 0; i < pmd->run.num_m2s_rings; i++) {
+		mq = (pmd->role == MEMIF_ROLE_SLAVE) ? &pmd->rx_queues[i] :
+		    &pmd->tx_queues[i];
+		mq->n_pkts = 0;
+		mq->n_bytes = 0;
+		mq->n_err = 0;
+	}
+}
+
+static int
+memif_rx_queue_intr_enable(struct rte_eth_dev *dev, uint16_t qid __rte_unused)
+{
+	struct pmd_internals *pmd = dev->data->dev_private;
+
+	MIF_LOG(WARNING, "%s: Interrupt mode not supported.",
+		rte_vdev_device_name(pmd->vdev));
+
+	/* Enable MEMIF interrupts. */
+	/* pmd->rx_queues[qid].ring->flags  &= ~MEMIF_RING_FLAG_MASK_INT; */
+
+	/*
+	 * TODO: Tell dpdk to use interrupt mode.
+	 *
+	 * return rte_intr_enable(&pmd->rx_queues[qid].intr_handle);
+	 */
+	return -1;
+}
+
+static int
+memif_rx_queue_intr_disable(struct rte_eth_dev *dev, uint16_t qid __rte_unused)
+{
+	struct pmd_internals *pmd __rte_unused = dev->data->dev_private;
+
+	/* Disable MEMIF interrupts. */
+	/* pmd->rx_queues[qid].ring->flags |= MEMIF_RING_FLAG_MASK_INT; */
+
+	/*
+	 * TODO: Tell dpdk to use polling mode.
+	 *
+	 * return rte_intr_disable(&pmd->rx_queues[qid].intr_handle);
+	 */
+	return 0;
+}
+
+static const struct eth_dev_ops ops = {
+	.dev_start = memif_dev_start,
+	.dev_infos_get = memif_dev_info,
+	.dev_configure = memif_dev_configure,
+	.tx_queue_setup = memif_tx_queue_setup,
+	.rx_queue_setup = memif_rx_queue_setup,
+	.rx_queue_intr_enable = memif_rx_queue_intr_enable,
+	.rx_queue_intr_disable = memif_rx_queue_intr_disable,
+	.link_update = memif_link_update,
+	.stats_get = memif_stats_get,
+	.stats_reset = memif_stats_reset,
+};
+
+static int
+memif_create(struct rte_vdev_device *vdev, enum memif_role_t role,
+	     memif_interface_id_t id, uint32_t flags,
+	     const char *socket_filename,
+	     memif_log2_ring_size_t log2_ring_size, uint8_t nrxq,
+	     uint8_t ntxq, uint16_t buffer_size, const char *secret,
+	     const char *eth_addr)
+{
+	int ret = 0;
+	struct rte_eth_dev *eth_dev;
+	struct rte_eth_dev_data *data;
+	struct pmd_internals *pmd;
+	const unsigned int numa_node = vdev->device.numa_node;
+	const char *name = rte_vdev_device_name(vdev);
+
+	if (flags & ETH_MEMIF_FLAG_ZERO_COPY) {
+		MIF_LOG(ERR, "Zero-copy not supported.");
+		return -1;
+	}
+
+	eth_dev = rte_eth_vdev_allocate(vdev, sizeof(*pmd));
+	if (eth_dev == NULL) {
+		MIF_LOG(ERR, "%s: Unable to allocate device struct.", name);
+		return -1;
+	}
+
+	pmd = eth_dev->data->dev_private;
+	memset(pmd, 0, sizeof(*pmd));
+
+	pmd->if_index = id;
+	pmd->vdev = vdev;
+	pmd->id = id;
+	pmd->flags = flags;
+	pmd->flags |= ETH_MEMIF_FLAG_DISABLED;
+	pmd->role = role;
+	ret = memif_socket_init(eth_dev, socket_filename);
+	if (ret < 0)
+		return ret;
+
+	memset(pmd->secret, 0, sizeof(char) * 24);
+	if (secret != NULL)
+		strncpy(pmd->secret, secret,
+			(strlen(secret) >= 24) ? 24 : strlen(secret));
+
+	pmd->cfg.log2_ring_size = ETH_MEMIF_DEFAULT_RING_SIZE;
+	if (log2_ring_size != 0)
+		pmd->cfg.log2_ring_size = log2_ring_size;
+	pmd->cfg.num_s2m_rings = ETH_MEMIF_DEFAULT_NRXQ;
+	pmd->cfg.num_m2s_rings = ETH_MEMIF_DEFAULT_NTXQ;
+
+	if (nrxq != 0) {
+		if (role == MEMIF_ROLE_SLAVE)
+			pmd->cfg.num_m2s_rings = nrxq;
+		else
+			pmd->cfg.num_s2m_rings = nrxq;
+	}
+	if (ntxq != 0) {
+		if (role == MEMIF_ROLE_SLAVE)
+			pmd->cfg.num_s2m_rings = ntxq;
+		else
+			pmd->cfg.num_m2s_rings = ntxq;
+	}
+
+	pmd->cfg.buffer_size = ETH_MEMIF_DEFAULT_BUFFER_SIZE;
+	if (buffer_size != 0)
+		pmd->cfg.buffer_size = buffer_size;
+
+	/* FIXME: generate mac? */
+	if (eth_addr == NULL)
+		eth_addr = ETH_MEMIF_DEFAULT_ETH_ADDR;
+
+	sscanf(eth_addr, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
+	       &pmd->eth_addr.addr_bytes[0], &pmd->eth_addr.addr_bytes[1],
+	       &pmd->eth_addr.addr_bytes[2], &pmd->eth_addr.addr_bytes[3],
+	       &pmd->eth_addr.addr_bytes[4], &pmd->eth_addr.addr_bytes[5]);
+
+	data = eth_dev->data;
+	data->dev_private = pmd;
+	data->numa_node = numa_node;
+	data->mac_addrs = &pmd->eth_addr;
+
+	eth_dev->dev_ops = &ops;
+	eth_dev->device = &vdev->device;
+	eth_dev->rx_pkt_burst = eth_memif_rx;
+	eth_dev->tx_pkt_burst = eth_memif_tx;
+
+	rte_eth_dev_probing_finish(eth_dev);
+
+	return ret;
+}
+
+static int
+memif_set_role(const char *key __rte_unused, const char *value,
+	       void *extra_args)
+{
+	enum memif_role_t *role = (enum memif_role_t *)extra_args;
+	if (strstr(value, "master") != NULL) {
+		*role = MEMIF_ROLE_MASTER;
+	} else if (strstr(value, "slave") != NULL) {
+		*role = MEMIF_ROLE_SLAVE;
+	} else {
+		MIF_LOG(ERR, "Unknown role: %s.", value);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int
+memif_set_zc(const char *key __rte_unused, const char *value, void *extra_args)
+{
+	uint32_t *flags = (uint32_t *) extra_args;
+
+	if (strstr(value, "yes") != NULL) {
+		*flags |= ETH_MEMIF_FLAG_ZERO_COPY;
+	} else if (strstr(value, "no") != NULL) {
+		*flags &= ~ETH_MEMIF_FLAG_ZERO_COPY;
+	} else {
+		MIF_LOG(ERR, "Failed to parse zero-copy param: %s.", value);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int
+memif_set_id(const char *key __rte_unused, const char *value, void *extra_args)
+{
+	memif_interface_id_t *id = (memif_interface_id_t *) extra_args;
+	/* even if parsing fails, 0 is a valid id */
+	*id = strtoul(value, NULL, 10);
+	return 0;
+}
+
+static int
+memif_set_bs(const char *key __rte_unused, const char *value, void *extra_args)
+{
+	unsigned long int tmp;
+	uint16_t *buffer_size = (uint16_t *) extra_args;
+
+	tmp = strtoul(value, NULL, 10);
+	if ((tmp == 0) || (tmp > 0xFFFF)) {
+		MIF_LOG(ERR, "Invalid buffer size: %s.", value);
+		return -EINVAL;
+	}
+	*buffer_size = tmp;
+	return 0;
+}
+
+static int
+memif_set_rs(const char *key __rte_unused, const char *value, void *extra_args)
+{
+	unsigned long int tmp;
+	memif_log2_ring_size_t *log2_ring_size =
+	    (memif_log2_ring_size_t *) extra_args;
+
+	tmp = strtoul(value, NULL, 10);
+	if ((tmp == 0) || (tmp > ETH_MEMIF_MAX_LOG2_RING_SIZE)) {
+		MIF_LOG(ERR, "Invalid ring size: %s (max %u).",
+			value, ETH_MEMIF_MAX_LOG2_RING_SIZE);
+		return -EINVAL;
+	}
+	*log2_ring_size = tmp;
+	return 0;
+}
+
+static int
+memif_set_nq(const char *key __rte_unused, const char *value, void *extra_args)
+{
+	unsigned long int tmp;
+	uint16_t *nq = (uint16_t *) extra_args;
+
+	tmp = strtoul(value, NULL, 10);
+	if ((tmp == 0) || (tmp > 0xFF)) {
+		MIF_LOG(ERR, "Invalid number of queues: %s.", value);
+		return -EINVAL;
+	}
+	*nq = tmp;
+	return 0;
+}
+
+/* check if directory exists and if we have permission to read/write */
+static inline int memif_check_socket_filename(const char *filename)
+{
+	char *dir = NULL, *tmp;
+	uint32_t idx;
+	int ret = 0;
+
+	tmp = strrchr(filename, '/');
+	if (tmp != NULL) {
+		idx = tmp - filename;
+		dir = rte_zmalloc("memif_tmp", sizeof(char) * (idx + 2), 0);
+		if (dir == NULL) {
+			MIF_LOG(ERR, "Failed to allocate memory.");
+			return -1;
+		}
+		strncpy(dir, filename, idx);
+	}
+
+	if ((dir == NULL) || (faccessat(-1, dir, F_OK | R_OK |
+					W_OK, AT_EACCESS) < 0)) {
+		MIF_LOG(ERR, "Invalid directory: %s.", dir);
+		ret = -EINVAL;
+	}
+
+	if (dir != NULL)
+		rte_free(dir);
+
+	return ret;
+}
+
+static int rte_pmd_memif_probe(struct rte_vdev_device *vdev)
+{
+	int ret = 0;
+	unsigned int i;
+	struct rte_kvargs *kvlist;
+	const struct rte_kvargs_pair *pair;
+
+	const char *name = rte_vdev_device_name(vdev);
+
+	enum memif_role_t role;
+	memif_interface_id_t id;
+
+	uint16_t buffer_size;
+	memif_log2_ring_size_t log2_ring_size;
+	uint8_t nrxq, ntxq;
+	const char *socket_filename;
+	const char *eth_addr;
+	uint32_t flags;
+	const char *secret;
+
+	MIF_LOG(INFO, "Initialize MEMIF: %s.", name);
+
+	kvlist = rte_kvargs_parse(rte_vdev_device_args(vdev), valid_arguments);
+
+	/* set default values */
+	role = MEMIF_ROLE_SLAVE;
+	flags = 0;
+	id = 0;
+	buffer_size = 2048;
+	log2_ring_size = 10;
+	nrxq = 1;
+	ntxq = 1;
+	socket_filename = ETH_MEMIF_DEFAULT_SOCKET_FILENAME;
+	secret = NULL;
+	eth_addr = NULL;
+
+	/* parse parameters */
+	if (kvlist != NULL) {
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_ROLE_ARG) == 1) {
+			ret = rte_kvargs_process(kvlist, ETH_MEMIF_ROLE_ARG,
+						 &memif_set_role, &role);
+			if (ret < 0)
+				goto exit;
+		}
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_ID_ARG) == 1) {
+			ret = rte_kvargs_process(kvlist, ETH_MEMIF_ID_ARG,
+						 &memif_set_id, &id);
+			if (ret < 0)
+				goto exit;
+		}
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_BUFFER_SIZE_ARG) == 1) {
+			ret =
+			    rte_kvargs_process(kvlist,
+					       ETH_MEMIF_BUFFER_SIZE_ARG,
+					       &memif_set_bs, &buffer_size);
+			if (ret < 0)
+				goto exit;
+		}
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_RING_SIZE_ARG) == 1) {
+			ret =
+			    rte_kvargs_process(kvlist, ETH_MEMIF_RING_SIZE_ARG,
+					       &memif_set_rs, &log2_ring_size);
+			if (ret < 0)
+				goto exit;
+		}
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_NRXQ_ARG) == 1) {
+			ret = rte_kvargs_process(kvlist, ETH_MEMIF_NRXQ_ARG,
+						 &memif_set_nq, &nrxq);
+			if (ret < 0)
+				goto exit;
+		}
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_NTXQ_ARG) == 1) {
+			ret = rte_kvargs_process(kvlist, ETH_MEMIF_NTXQ_ARG,
+						 &memif_set_nq, &ntxq);
+			if (ret < 0)
+				goto exit;
+		}
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_SOCKET_ARG) == 1) {
+			for (i = 0; i < kvlist->count; i++) {
+				pair = &kvlist->pairs[i];
+				if (strcmp(pair->key, ETH_MEMIF_SOCKET_ARG) ==
+				    0) {
+					socket_filename = pair->value;
+					ret =
+					    memif_check_socket_filename
+					    (socket_filename);
+					if (ret < 0)
+						goto exit;
+				}
+			}
+		}
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_MAC_ARG) == 1) {
+			for (i = 0; i < kvlist->count; i++) {
+				pair = &kvlist->pairs[i];
+				if (strcmp(pair->key, ETH_MEMIF_MAC_ARG) == 0) {
+					eth_addr = pair->value;
+				}
+			}
+		}
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_ZC_ARG) == 1) {
+			ret = rte_kvargs_process(kvlist, ETH_MEMIF_ZC_ARG,
+						 &memif_set_zc, &flags);
+			if (ret < 0)
+				goto exit;
+		}
+		if (rte_kvargs_count(kvlist, ETH_MEMIF_SECRET_ARG) == 1) {
+			for (i = 0; i < kvlist->count; i++) {
+				pair = &kvlist->pairs[i];
+				if (strcmp(pair->key, ETH_MEMIF_SECRET_ARG) ==
+				    0) {
+					secret = pair->value;
+				}
+			}
+		}
+	}
+
+	/* create interface */
+	ret =
+	    memif_create(vdev, role, id, flags, socket_filename, log2_ring_size,
+			 nrxq, ntxq, buffer_size, secret, eth_addr);
+
+ exit:
+	if (kvlist != NULL)
+		rte_kvargs_free(kvlist);
+	return ret;
+}
+
+static int rte_pmd_memif_remove(struct rte_vdev_device *vdev)
+{
+	struct rte_eth_dev *eth_dev;
+
+	eth_dev = rte_eth_dev_allocated(rte_vdev_device_name(vdev));
+	if (eth_dev == NULL)
+		return 0;
+
+	struct pmd_internals *pmd = eth_dev->data->dev_private;
+
+	memif_msg_enq_disconnect(pmd->cc, "Invalid message size", 0);
+	memif_disconnect(eth_dev);
+
+	memif_socket_remove_device(pmd);
+
+	pmd->vdev = NULL;
+
+	rte_free(eth_dev->data->dev_private);
+
+	rte_eth_dev_release_port(eth_dev);
+
+	return 0;
+}
+
+static struct rte_vdev_driver pmd_memif_drv = {
+	.probe = rte_pmd_memif_probe,
+	.remove = rte_pmd_memif_remove,
+};
+
+RTE_PMD_REGISTER_VDEV(net_memif, pmd_memif_drv);
+RTE_PMD_REGISTER_ALIAS(net_memif, eth_memif);
+RTE_PMD_REGISTER_PARAM_STRING(net_memif,
+			      ETH_MEMIF_ID_ARG "=<int>"
+			      ETH_MEMIF_ROLE_ARG "=<string>"
+			      ETH_MEMIF_BUFFER_SIZE_ARG "=<int>"
+			      ETH_MEMIF_RING_SIZE_ARG "=<int>"
+			      ETH_MEMIF_NRXQ_ARG "=<int>"
+			      ETH_MEMIF_NTXQ_ARG "=<int>"
+			      ETH_MEMIF_SOCKET_ARG "=<string>"
+			      ETH_MEMIF_MAC_ARG "=xx:xx:xx:xx:xx:xx"
+			      ETH_MEMIF_ZC_ARG "=<string>"
+			      ETH_MEMIF_SECRET_ARG "=<string>");
+
+RTE_INIT(memif_init_log)
+{
+	memif_logtype = rte_log_register("pmd.net.memif");
+	if (memif_logtype >= 0)
+		rte_log_set_level(memif_logtype, RTE_LOG_NOTICE);
+}
diff --git a/drivers/net/memif/rte_eth_memif.h b/drivers/net/memif/rte_eth_memif.h
new file mode 100644
index 000000000..bbd79e1a5
--- /dev/null
+++ b/drivers/net/memif/rte_eth_memif.h
@@ -0,0 +1,189 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2018 Cisco Systems, Inc.  All rights reserved.
+ */
+
+#ifndef _RTE_ETH_MEMIF_H_
+#define _RTE_ETH_MEMIF_H_
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif				/* GNU_SOURCE */
+
+#include <stdio.h>
+#include <sys/queue.h>
+
+#include <rte_ethdev_driver.h>
+#include <rte_ether.h>
+#include <rte_timer.h>
+#include <rte_interrupts.h>
+
+#include <memif.h>
+
+/* generate mac? */
+#define ETH_MEMIF_DEFAULT_ETH_ADDR		"01:ab:23:cd:45:ef"
+
+#define ETH_MEMIF_DEFAULT_SOCKET_FILENAME	"/tmp/memif.sock"
+#define ETH_MEMIF_DEFAULT_RING_SIZE		10
+#define ETH_MEMIF_DEFAULT_NRXQ			1
+#define ETH_MEMIF_DEFAULT_NTXQ			1
+#define ETH_MEMIF_DEFAULT_BUFFER_SIZE		2048
+
+#define ETH_MEMIF_MAX_NUM_Q_PAIRS		256
+#define ETH_MEMIF_MAX_LOG2_RING_SIZE		14
+#define ETH_MEMIF_MAX_REGION_IDX		255
+
+int memif_logtype;
+
+#define memif_min(a,b) (((a) < (b)) ? (a) : (b))
+
+#define MIF_LOG(level, fmt, args...) \
+do {							\
+	rte_log(RTE_LOG_ ## level, memif_logtype,	\
+		"%s(): " fmt "\n", __func__, ##args);	\
+} while (0)
+
+enum memif_role_t {
+	MEMIF_ROLE_MASTER = 0,
+	MEMIF_ROLE_SLAVE = 1,
+};
+
+/* Shared memory region. */
+struct memif_region {
+	void *addr;
+	memif_region_size_t region_size;
+	int fd;
+	uint32_t buffer_offset;
+};
+
+struct memif_queue {
+	struct rte_mempool *mempool;
+	uint16_t in_port;
+
+	struct pmd_internals *pmd;
+
+	struct rte_intr_handle intr_handle;
+
+	/* ring info */
+	memif_ring_type_t type;
+	memif_ring_t *ring;
+	memif_log2_ring_size_t log2_ring_size;
+
+	memif_region_index_t region;
+	memif_region_offset_t offset;
+
+	uint16_t last_head;
+	uint16_t last_tail;
+	uint32_t *buffers;
+
+	/* rx/tx info */
+	uint64_t n_pkts;
+	uint64_t n_bytes;
+	uint64_t n_err;
+};
+
+struct pmd_internals {
+	int if_index;
+	memif_interface_id_t id;
+	enum memif_role_t role;
+	uint32_t flags;
+#define ETH_MEMIF_FLAG_CONNECTING	(1 << 0)
+#define ETH_MEMIF_FLAG_CONNECTED	(1 << 1)
+#define ETH_MEMIF_FLAG_ZERO_COPY	(1 << 2)
+/* device has not been configured and can not accept connection requests */
+#define ETH_MEMIF_FLAG_DISABLED		(1 << 3)
+
+	struct ether_addr eth_addr;
+	char *socket_filename;
+	char secret[24];
+
+	struct memif_control_channel *cc;
+
+	struct memif_region *regions;
+	uint8_t regions_num;
+
+	struct memif_queue *rx_queues;
+	struct memif_queue *tx_queues;
+
+	/* remote info */
+	char remote_name[64];
+	char remote_if_name[64];
+
+	/* Configured parameters (max values) */
+	struct {
+		memif_log2_ring_size_t log2_ring_size;
+		uint8_t num_s2m_rings;
+		uint8_t num_m2s_rings;
+		uint16_t buffer_size;
+	} cfg;
+
+	/* Parameters used in active connection */
+	struct {
+		memif_log2_ring_size_t log2_ring_size;
+		uint8_t num_s2m_rings;
+		uint8_t num_m2s_rings;
+		uint16_t buffer_size;
+	} run;
+
+	char local_disc_string[96];
+	char remote_disc_string[96];
+
+	/* vdev handle */
+	struct rte_vdev_device *vdev;
+};
+
+void memif_free_regions(struct pmd_internals *pmd);
+
+/*
+ * Finalize connection establishment process. Map shared memory file
+ * (master role), initialize ring queue, set link status up.
+ */
+int memif_connect(struct pmd_internals *pmd);
+
+/*
+ * Create shared memory file and initialize ring queue.
+ * Only called by slave when establishing connection
+ */
+int memif_init_regions_and_queues(struct pmd_internals *pmd);
+
+const char *memif_version(void);
+
+#ifndef MFD_HUGETLB
+#ifndef __NR_memfd_create
+
+#if defined __x86_64__
+#define __NR_memfd_create 319
+#elif defined __arm__
+#define __NR_memfd_create 385
+#elif defined __aarch64__
+#define __NR_memfd_create 279
+#else
+#error "__NR_memfd_create unknown for this architecture"
+#endif
+
+#endif				/* __NR_memfd_create */
+
+static inline int memfd_create(const char *name, unsigned int flags)
+{
+	return syscall(__NR_memfd_create, name, flags);
+}
+#endif				/* MFD_HUGETLB */
+
+#ifndef F_LINUX_SPECIFIC_BASE
+#define F_LINUX_SPECIFIC_BASE 1024
+#endif
+
+#ifndef MFD_ALLOW_SEALING
+#define MFD_ALLOW_SEALING       0x0002U
+#endif
+
+#ifndef F_ADD_SEALS
+#define F_ADD_SEALS (F_LINUX_SPECIFIC_BASE + 9)
+#define F_GET_SEALS (F_LINUX_SPECIFIC_BASE + 10)
+
+#define F_SEAL_SEAL     0x0001	/* prevent further seals from being set */
+#define F_SEAL_SHRINK   0x0002	/* prevent file from shrinking */
+#define F_SEAL_GROW     0x0004	/* prevent file from growing */
+#define F_SEAL_WRITE    0x0008	/* prevent writes */
+#endif
+
+#endif				/* RTE_ETH_MEMIF_H */
diff --git a/drivers/net/memif/rte_pmd_memif_version.map b/drivers/net/memif/rte_pmd_memif_version.map
new file mode 100644
index 000000000..aee560afa
--- /dev/null
+++ b/drivers/net/memif/rte_pmd_memif_version.map
@@ -0,0 +1,4 @@ 
+DPDK_2.0 {
+
+        local: *;
+};
diff --git a/drivers/net/meson.build b/drivers/net/meson.build
index 980eec233..b0becbf31 100644
--- a/drivers/net/meson.build
+++ b/drivers/net/meson.build
@@ -21,6 +21,7 @@  drivers = ['af_packet',
 	'ixgbe',
 	'kni',
 	'liquidio',
+	'memif',
 	'mlx4',
 	'mlx5',
 	'mvneta',
diff --git a/mk/rte.app.mk b/mk/rte.app.mk
index 5699d979d..f236c5ebc 100644
--- a/mk/rte.app.mk
+++ b/mk/rte.app.mk
@@ -168,6 +168,7 @@  ifeq ($(CONFIG_RTE_LIBRTE_KNI),y)
 _LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_KNI)        += -lrte_pmd_kni
 endif
 _LDLIBS-$(CONFIG_RTE_LIBRTE_LIO_PMD)        += -lrte_pmd_lio
+_LDLIBS-$(CONFIG_RTE_LIBRTE_PMD_MEMIF)      += -lrte_pmd_memif
 ifeq ($(CONFIG_RTE_LIBRTE_MLX4_DLOPEN_DEPS),y)
 _LDLIBS-$(CONFIG_RTE_LIBRTE_MLX4_PMD)       += -lrte_pmd_mlx4 -ldl
 else