[v13,2/2] eal: support for VFIO-PCI VF token

diff --git a/doc/guides/linux_gsg/linux_drivers.rst b/doc/guides/linux_gsg/linux_drivers.rst
index 238f3e900..910397243 100644
--- a/doc/guides/linux_gsg/linux_drivers.rst
+++ b/doc/guides/linux_gsg/linux_drivers.rst
@@ -72,11 +72,44 @@  Note that in order to use VFIO, your kernel must support it.
 VFIO kernel modules have been included in the Linux kernel since version 3.6.0 and are usually present by default,
 however please consult your distributions documentation to make sure that is the case.
 
+The ``vfio-pci`` module since Linux version 5.7 supports the creation of virtual
+functions. After the PF is bound to vfio-pci module, the user can create the VFs
+by sysfs interface, and these VFs are bound to vfio-pci module automatically.
+
+When the PF is bound to vfio-pci, it has initial VF token generated by random. For
+security reason, this token is write only, the user can't read it from the kernel
+directly. For accessing the VF, the user needs to start the PF with token parameter
+to setup a VF token (uuid format), then the VF can be accessed with this new known
+VF token.
+
+DPDK will use the EAL parameter ``--vfio-vf-token`` to specify the VF token value to
+PF and its related VFs, this VF token will be shared in all VFIO devices, including
+the different PFs.
+
+.. code-block:: console
+
+    1. Generate the VF token by uuid command
+        14d63f20-8445-11ea-8900-1f9ce7d5650d
+
+    2. sudo modprobe vfio-pci enable_sriov=1
+
+    2. ./usertools/dpdk-devbind.py -b vfio-pci 0000:86:00.0
+
+    3. echo 2 > /sys/bus/pci/devices/0000:86:00.0/sriov_numvfs
+
+    4. Start the PF:
+        ./x86_64-native-linux-gcc/app/testpmd -l 22-25 -n 4 -w 86:00.0 \
+         --vfio-vf-token=14d63f20-8445-11ea-8900-1f9ce7d5650d --file-prefix=pf -- -i
+
+    5. Start the VF:
+        ./x86_64-native-linux-gcc/app/testpmd -l 26-29 -n 4 -w 86:02.0 \
+         --vfio-vf-token=14d63f20-8445-11ea-8900-1f9ce7d5650d --file-prefix=vf0 -- -i
+
 Also, to use VFIO, both kernel and BIOS must support and be configured to use IO virtualization (such as Intel® VT-d).
 
 .. note::
 
-    ``vfio-pci`` module doesn't support the creation of virtual functions.
+    ``vfio-pci`` module doesn't support the creation of virtual functions before Linux version 5.7.
 
 For proper operation of VFIO when running DPDK applications as a non-privileged user, correct permissions should also be set up.
 This can be done by using the DPDK setup script (called dpdk-setup.sh and located in the usertools directory).
diff --git a/doc/guides/linux_gsg/linux_eal_parameters.rst b/doc/guides/linux_gsg/linux_eal_parameters.rst
index b2cc60e44..bd3977cb3 100644
--- a/doc/guides/linux_gsg/linux_eal_parameters.rst
+++ b/doc/guides/linux_gsg/linux_eal_parameters.rst
@@ -40,6 +40,10 @@  Device-related options
 
     Use specified interrupt mode for devices bound to VFIO kernel driver.
 
+*   ``--vfio-vf-token <uuid>``
+
+    Use specified VF token for devices bound to VFIO kernel driver.
+
 Multiprocessing-related options
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
diff --git a/doc/guides/rel_notes/release_20_05.rst b/doc/guides/rel_notes/release_20_05.rst
index c287cb48a..b19b03f83 100644
--- a/doc/guides/rel_notes/release_20_05.rst
+++ b/doc/guides/rel_notes/release_20_05.rst
@@ -93,6 +93,12 @@  New Features
   * Added new query: ``rte_flow_get_aged_flows`` to get the aged-out flows
     contexts from the port.
 
+* **Added the support for vfio-pci new VF token interface.**
+
+  Since Linux version 5.7, vfio-pci supports a shared VF token (UUID) to represent
+  the trust between SR-IOV PF and the created VFs. Update the method to gain access
+  to the PF and VFs devices by appending the VF token parameter.
+
 * **Updated Amazon ena driver.**
 
   Updated ena PMD with new features and improvements, including:
diff --git a/lib/librte_eal/common/eal_common_options.c b/lib/librte_eal/common/eal_common_options.c
index 418731ca4..dbce919ad 100644
--- a/lib/librte_eal/common/eal_common_options.c
+++ b/lib/librte_eal/common/eal_common_options.c
@@ -89,6 +89,7 @@  eal_long_options[] = {
 	{OPT_SYSLOG,            1, NULL, OPT_SYSLOG_NUM           },
 	{OPT_VDEV,              1, NULL, OPT_VDEV_NUM             },
 	{OPT_VFIO_INTR,         1, NULL, OPT_VFIO_INTR_NUM        },
+	{OPT_VFIO_VF_TOKEN,     1, NULL, OPT_VFIO_VF_TOKEN_NUM    },
 	{OPT_VMWARE_TSC_MAP,    0, NULL, OPT_VMWARE_TSC_MAP_NUM   },
 	{OPT_LEGACY_MEM,        0, NULL, OPT_LEGACY_MEM_NUM       },
 	{OPT_SINGLE_FILE_SEGMENTS, 0, NULL, OPT_SINGLE_FILE_SEGMENTS_NUM},
@@ -222,6 +223,7 @@  eal_reset_internal_config(struct internal_config *internal_cfg)
 
 	/* if set to NONE, interrupt mode is determined automatically */
 	internal_cfg->vfio_intr_mode = RTE_INTR_MODE_NONE;
+	memset(internal_cfg->vfio_vf_token, 0, sizeof(rte_uuid_t));
 
 #ifdef RTE_LIBEAL_USE_HPET
 	internal_cfg->no_hpet = 0;
diff --git a/lib/librte_eal/common/eal_internal_cfg.h b/lib/librte_eal/common/eal_internal_cfg.h
index a42f34923..28154f0ef 100644
--- a/lib/librte_eal/common/eal_internal_cfg.h
+++ b/lib/librte_eal/common/eal_internal_cfg.h
@@ -72,6 +72,8 @@  struct internal_config {
 	volatile int syslog_facility;	  /**< facility passed to openlog() */
 	/** default interrupt mode for VFIO */
 	volatile enum rte_intr_mode vfio_intr_mode;
+	/** the shared VF token for VFIO-PCI bound PF and VFs devices */
+	rte_uuid_t vfio_vf_token;
 	char *hugefile_prefix;      /**< the base filename of hugetlbfs files */
 	char *hugepage_dir;         /**< specific hugetlbfs directory to use */
 	char *user_mbuf_pool_ops_name;
diff --git a/lib/librte_eal/common/eal_options.h b/lib/librte_eal/common/eal_options.h
index 90ead1b7c..cd5fd01f2 100644
--- a/lib/librte_eal/common/eal_options.h
+++ b/lib/librte_eal/common/eal_options.h
@@ -67,6 +67,8 @@  enum {
 	OPT_VDEV_NUM,
 #define OPT_VFIO_INTR         "vfio-intr"
 	OPT_VFIO_INTR_NUM,
+#define OPT_VFIO_VF_TOKEN     "vfio-vf-token"
+	OPT_VFIO_VF_TOKEN_NUM,
 #define OPT_VMWARE_TSC_MAP    "vmware-tsc-map"
 	OPT_VMWARE_TSC_MAP_NUM,
 #define OPT_LEGACY_MEM    "legacy-mem"
diff --git a/lib/librte_eal/freebsd/eal.c b/lib/librte_eal/freebsd/eal.c
index 540b7d38c..07f17f182 100644
--- a/lib/librte_eal/freebsd/eal.c
+++ b/lib/librte_eal/freebsd/eal.c
@@ -1002,6 +1002,10 @@  rte_eal_vfio_intr_mode(void)
 	return RTE_INTR_MODE_NONE;
 }
 
+void rte_eal_vfio_get_vf_token(__rte_unused rte_uuid_t vf_token)
+{
+}
+
 int rte_vfio_setup_device(__rte_unused const char *sysfs_base,
 		      __rte_unused const char *dev_addr,
 		      __rte_unused int *vfio_dev_fd,
diff --git a/lib/librte_eal/include/rte_eal.h b/lib/librte_eal/include/rte_eal.h
index 2f9ed298d..744370013 100644
--- a/lib/librte_eal/include/rte_eal.h
+++ b/lib/librte_eal/include/rte_eal.h
@@ -21,6 +21,7 @@ 
 #include <rte_bus.h>
 
 #include <rte_pci_dev_feature_defs.h>
+#include <rte_uuid.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -438,6 +439,17 @@  int rte_eal_create_uio_dev(void);
  */
 enum rte_intr_mode rte_eal_vfio_intr_mode(void);
 
+
+/**
+ * Copy the user-configured vfio VF token.
+ *
+ * @param vf_token
+ *   vfio VF token configured with the command line is copied
+ *   into this parameter, zero uuid by default.
+ */
+__rte_experimental
+void rte_eal_vfio_get_vf_token(rte_uuid_t vf_token);
+
 /**
  * A wrap API for syscall gettid.
  *
diff --git a/lib/librte_eal/linux/eal.c b/lib/librte_eal/linux/eal.c
index aa72d3650..f394c281c 100644
--- a/lib/librte_eal/linux/eal.c
+++ b/lib/librte_eal/linux/eal.c
@@ -558,6 +558,7 @@  eal_usage(const char *prgname)
 	       "  --"OPT_FILE_PREFIX"       Prefix for hugepage filenames\n"
 	       "  --"OPT_CREATE_UIO_DEV"    Create /dev/uioX (usually done by hotplug)\n"
 	       "  --"OPT_VFIO_INTR"         Interrupt mode for VFIO (legacy|msi|msix)\n"
+	       "  --"OPT_VFIO_VF_TOKEN"     VF token (UUID) shared between SR-IOV PF and VFs\n"
 	       "  --"OPT_LEGACY_MEM"        Legacy memory mode (no dynamic allocation, contiguous segments)\n"
 	       "  --"OPT_SINGLE_FILE_SEGMENTS" Put all hugepage memory in single files\n"
 	       "  --"OPT_MATCH_ALLOCATIONS" Free hugepages exactly as allocated\n"
@@ -649,6 +650,19 @@  eal_parse_vfio_intr(const char *mode)
 	return -1;
 }
 
+static int
+eal_parse_vfio_vf_token(const char *vf_token)
+{
+	rte_uuid_t uuid;
+
+	if (!rte_uuid_parse(vf_token, uuid)) {
+		rte_uuid_copy(internal_config.vfio_vf_token, uuid);
+		return 0;
+	}
+
+	return -1;
+}
+
 /* Parse the arguments for --log-level only */
 static void
 eal_log_level_parse(int argc, char **argv)
@@ -795,6 +809,16 @@  eal_parse_args(int argc, char **argv)
 			}
 			break;
 
+		case OPT_VFIO_VF_TOKEN_NUM:
+			if (eal_parse_vfio_vf_token(optarg) < 0) {
+				RTE_LOG(ERR, EAL, "invalid parameters for --"
+						OPT_VFIO_VF_TOKEN "\n");
+				eal_usage(prgname);
+				ret = -1;
+				goto out;
+			}
+			break;
+
 		case OPT_CREATE_UIO_DEV_NUM:
 			internal_config.create_uio_dev = 1;
 			break;
@@ -1367,6 +1391,11 @@  rte_eal_vfio_intr_mode(void)
 	return internal_config.vfio_intr_mode;
 }
 
+void rte_eal_vfio_get_vf_token(rte_uuid_t vf_token)
+{
+	rte_uuid_copy(vf_token, internal_config.vfio_vf_token);
+}
+
 int
 rte_eal_check_module(const char *module_name)
 {
diff --git a/lib/librte_eal/linux/eal_vfio.c b/lib/librte_eal/linux/eal_vfio.c
index d26e1649a..5b2f6b305 100644
--- a/lib/librte_eal/linux/eal_vfio.c
+++ b/lib/librte_eal/linux/eal_vfio.c
@@ -712,6 +712,7 @@  rte_vfio_setup_device(const char *sysfs_base, const char *dev_addr,
 	int vfio_container_fd;
 	int vfio_group_fd;
 	int iommu_group_num;
+	rte_uuid_t vf_token;
 	int i, ret;
 
 	/* get group number */
@@ -895,6 +896,23 @@  rte_vfio_setup_device(const char *sysfs_base, const char *dev_addr,
 				t->type_id, t->name);
 	}
 
+	rte_eal_vfio_get_vf_token(vf_token);
+
+	/* get a file descriptor for the device with VF token firstly */
+	if (!rte_uuid_is_null(vf_token)) {
+		char vf_token_str[RTE_UUID_STRLEN];
+		char dev[PATH_MAX];
+
+		rte_uuid_unparse(vf_token, vf_token_str, sizeof(vf_token_str));
+		snprintf(dev, sizeof(dev),
+			 "%s vf_token=%s", dev_addr, vf_token_str);
+
+		*vfio_dev_fd = ioctl(vfio_group_fd, VFIO_GROUP_GET_DEVICE_FD,
+				     dev);
+		if (*vfio_dev_fd >= 0)
+			goto dev_get_info;
+	}
+
 	/* get a file descriptor for the device */
 	*vfio_dev_fd = ioctl(vfio_group_fd, VFIO_GROUP_GET_DEVICE_FD, dev_addr);
 	if (*vfio_dev_fd < 0) {
@@ -909,6 +927,7 @@  rte_vfio_setup_device(const char *sysfs_base, const char *dev_addr,
 		return -1;
 	}
 
+dev_get_info:
 	/* test and setup the device */
 	ret = ioctl(*vfio_dev_fd, VFIO_DEVICE_GET_INFO, device_info);
 	if (ret) {
diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
index 6088e7f6c..f7043af69 100644
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -373,6 +373,7 @@  EXPERIMENTAL {
 	__rte_trace_point_register;
 	per_lcore_trace_mem;
 	per_lcore_trace_point_sz;
+	rte_eal_vfio_get_vf_token;
 	rte_log_can_log;
 	rte_thread_getname;
 	rte_trace_dump;