[v4,09/14] bus/vmbus: open subchannels

Message ID 20220418042915.5765-10-srikanth.k@oneconvergence.com (mailing list archive)
State Superseded, archived
Headers
Series add FreeBSD support to VMBUS & NetVSC PMDs |

Checks

Context Check Description
ci/checkpatch warning coding style issues

Commit Message

Srikanth Kaka April 18, 2022, 4:29 a.m. UTC
  In FreeBSD, unlike Linux there is no sub-channel open callback that
could be called by HV_UIO driver upon their grant by the hypervisor.
Thus the PMD makes an IOCTL to the HV_UIO to open the sub-channels

On Linux, the vmbus_uio_subchan_open() will always return success
as the Linux HV_UIO opens them implicitly.

Signed-off-by: Srikanth Kaka <srikanth.k@oneconvergence.com>
Signed-off-by: Vag Singh <vag.singh@oneconvergence.com>
Signed-off-by: Anand Thulasiram <avelu@juniper.net>
---
 drivers/bus/vmbus/freebsd/vmbus_uio.c | 30 +++++++++++++++++++++++++++
 drivers/bus/vmbus/linux/vmbus_uio.c   | 12 +++++++++++
 drivers/bus/vmbus/private.h           |  1 +
 drivers/bus/vmbus/rte_bus_vmbus.h     | 10 +++++++++
 drivers/bus/vmbus/version.map         |  1 +
 drivers/bus/vmbus/vmbus_channel.c     |  5 +++++
 6 files changed, 59 insertions(+)
  

Comments

Stephen Hemminger April 19, 2022, 3 p.m. UTC | #1
On Mon, 18 Apr 2022 09:59:10 +0530
Srikanth Kaka <srikanth.k@oneconvergence.com> wrote:

> diff --git a/drivers/bus/vmbus/version.map b/drivers/bus/vmbus/version.map
> index 3cadec7fae..3509d4fc14 100644
> --- a/drivers/bus/vmbus/version.map
> +++ b/drivers/bus/vmbus/version.map
> @@ -23,6 +23,7 @@ DPDK_22 {
>  	rte_vmbus_subchan_open;
>  	rte_vmbus_unmap_device;
>  	rte_vmbus_unregister;
> +	rte_vmbus_ioctl;
>  
>  	local: *;
>  };

Adding ioctl is fine, probably would have done on Linux if the kernel
community would have allowed it...

But it needs to go in EXPERIMENTAL section per DPDK policy.
  

Patch

diff --git a/drivers/bus/vmbus/freebsd/vmbus_uio.c b/drivers/bus/vmbus/freebsd/vmbus_uio.c
index 6b43b4349f..7e4e9723cb 100644
--- a/drivers/bus/vmbus/freebsd/vmbus_uio.c
+++ b/drivers/bus/vmbus/freebsd/vmbus_uio.c
@@ -25,6 +25,9 @@ 
  */
 #define UH_SUBCHAN_MASK_SHIFT  8
 
+/* ioctl */
+#define HVIOOPENSUBCHAN     _IOW('h', 14, uint32_t)
+
 const char *driver_name = "hv_uio";
 
 /* Check map names with kernel names */
@@ -151,3 +154,30 @@  const char *get_devname_os(void)
 {
 	return "/dev/hv_uio";
 }
+
+int vmbus_uio_subchan_open(struct rte_vmbus_device *dev, uint32_t subchan)
+{
+	struct mapped_vmbus_resource *uio_res;
+	int fd, err = 0;
+
+	uio_res = vmbus_uio_find_resource(dev);
+	if (!uio_res) {
+		VMBUS_LOG(ERR, "cannot find uio resource");
+		return -EINVAL;
+	}
+
+	fd = open(uio_res->path, O_RDWR);
+	if (fd < 0) {
+		VMBUS_LOG(ERR, "Cannot open %s: %s",
+				uio_res->path, strerror(errno));
+		return -1;
+	}
+
+	if (ioctl(fd, HVIOOPENSUBCHAN, &subchan)) {
+		VMBUS_LOG(ERR, "open subchan ioctl failed %s: %s",
+				uio_res->path, strerror(errno));
+		err = -1;
+	}
+	close(fd);
+	return err;
+}
diff --git a/drivers/bus/vmbus/linux/vmbus_uio.c b/drivers/bus/vmbus/linux/vmbus_uio.c
index 669551a4d4..d88cc97b5b 100644
--- a/drivers/bus/vmbus/linux/vmbus_uio.c
+++ b/drivers/bus/vmbus/linux/vmbus_uio.c
@@ -215,3 +215,15 @@  const char *get_devname_os(void)
 {
 	return "/dev/uio";
 }
+
+/*
+ * This is a stub function and it should always succeed.
+ * The Linux UIO kernel driver opens the subchannels implicitly.
+ */
+int vmbus_uio_subchan_open(struct rte_vmbus_device *dev,
+			   uint32_t subchan)
+{
+	RTE_SET_USED(dev);
+	RTE_SET_USED(subchan);
+	return 0;
+}
diff --git a/drivers/bus/vmbus/private.h b/drivers/bus/vmbus/private.h
index 1bca147e12..ea0276a6c6 100644
--- a/drivers/bus/vmbus/private.h
+++ b/drivers/bus/vmbus/private.h
@@ -116,6 +116,7 @@  bool vmbus_uio_subchannels_supported(const struct rte_vmbus_device *dev,
 int vmbus_uio_get_subchan(struct vmbus_channel *primary,
 			  struct vmbus_channel **subchan);
 int vmbus_uio_map_rings(struct vmbus_channel *chan);
+int vmbus_uio_subchan_open(struct rte_vmbus_device *device, uint32_t subchan);
 
 void vmbus_br_setup(struct vmbus_br *br, void *buf, unsigned int blen);
 
diff --git a/drivers/bus/vmbus/rte_bus_vmbus.h b/drivers/bus/vmbus/rte_bus_vmbus.h
index a24bad831d..c8cb4bc98c 100644
--- a/drivers/bus/vmbus/rte_bus_vmbus.h
+++ b/drivers/bus/vmbus/rte_bus_vmbus.h
@@ -404,6 +404,16 @@  void rte_vmbus_chan_dump(FILE *f, const struct vmbus_channel *chan);
  */
 void rte_vmbus_unregister(struct rte_vmbus_driver *driver);
 
+/**
+ * Perform IOCTL to VMBUS device
+ *
+ * @param device
+ *	A pointer to a rte_vmbus_device structure
+ * @param subchan
+ *	Count of subchannels to open
+ */
+int rte_vmbus_ioctl(struct rte_vmbus_device *device, uint32_t subchan);
+
 /** Helper for VMBUS device registration from driver instance */
 #define RTE_PMD_REGISTER_VMBUS(nm, vmbus_drv)		\
 	RTE_INIT(vmbusinitfn_ ##nm)			\
diff --git a/drivers/bus/vmbus/version.map b/drivers/bus/vmbus/version.map
index 3cadec7fae..3509d4fc14 100644
--- a/drivers/bus/vmbus/version.map
+++ b/drivers/bus/vmbus/version.map
@@ -23,6 +23,7 @@  DPDK_22 {
 	rte_vmbus_subchan_open;
 	rte_vmbus_unmap_device;
 	rte_vmbus_unregister;
+	rte_vmbus_ioctl;
 
 	local: *;
 };
diff --git a/drivers/bus/vmbus/vmbus_channel.c b/drivers/bus/vmbus/vmbus_channel.c
index 119b9b367e..9a8f6e3eef 100644
--- a/drivers/bus/vmbus/vmbus_channel.c
+++ b/drivers/bus/vmbus/vmbus_channel.c
@@ -365,6 +365,11 @@  int rte_vmbus_max_channels(const struct rte_vmbus_device *device)
 		return 1;
 }
 
+int rte_vmbus_ioctl(struct rte_vmbus_device *device, uint32_t subchan)
+{
+	return vmbus_uio_subchan_open(device, subchan);
+}
+
 /* Setup secondary channel */
 int rte_vmbus_subchan_open(struct vmbus_channel *primary,
 			   struct vmbus_channel **new_chan)