[PATCH v2] devargs: add blacklisting by linux interface name

[Chas Williams <3chas3@gmail.com>]

If a system is using deterministic interface names, it may be easier in
some cases to use the interface name to blacklist an interface.

Signed-off-by: Chas Williams <3chas3@gmail.com>
---
 app/test/test_devargs.c                     |  2 ++
 lib/librte_eal/common/eal_common_devargs.c  |  9 +++++++--
 lib/librte_eal/common/eal_common_options.c  |  2 +-
 lib/librte_eal/common/eal_common_pci.c      | 10 ++++++++--
 lib/librte_eal/common/include/rte_devargs.h |  2 ++
 lib/librte_eal/common/include/rte_pci.h     |  1 +
 lib/librte_eal/linuxapp/eal/eal_pci.c       | 15 +++++++++++++++
 7 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/app/test/test_devargs.c b/app/test/test_devargs.c
index f7fc59c..27855ff 100644
--- a/app/test/test_devargs.c
+++ b/app/test/test_devargs.c
@@ -73,6 +73,8 @@ test_devargs(void)
 		goto fail;
 	if (rte_eal_devargs_add(RTE_DEVTYPE_BLACKLISTED_PCI, "0000:01:00.1") < 0)
 		goto fail;
+	if (rte_eal_devargs_add(RTE_DEVTYPE_BLACKLISTED_PCI, "eth0") < 0)
+		goto fail;
 	if (rte_eal_devargs_type_count(RTE_DEVTYPE_WHITELISTED_PCI) != 2)
 		goto fail;
 	if (rte_eal_devargs_type_count(RTE_DEVTYPE_BLACKLISTED_PCI) != 2)
diff --git a/lib/librte_eal/common/eal_common_devargs.c b/lib/librte_eal/common/eal_common_devargs.c
index ec56165..1fb8bad 100644
--- a/lib/librte_eal/common/eal_common_devargs.c
+++ b/lib/librte_eal/common/eal_common_devargs.c
@@ -101,8 +101,13 @@ rte_eal_devargs_add(enum rte_devtype devtype, const char *devargs_str)
 	case RTE_DEVTYPE_BLACKLISTED_PCI:
 		/* try to parse pci identifier */
 		if (eal_parse_pci_BDF(buf, &devargs->pci.addr) != 0 &&
-		    eal_parse_pci_DomBDF(buf, &devargs->pci.addr) != 0)
-			goto fail;
+		    eal_parse_pci_DomBDF(buf, &devargs->pci.addr) != 0) {
+			/* save as interface name instead */
+			ret = snprintf(devargs->pci.name,
+				       sizeof(devargs->pci.name), "%s", buf);
+			if (ret < 0 || ret >= (int)sizeof(devargs->pci.name))
+				goto fail;
+		}
 
 		break;
 	case RTE_DEVTYPE_VIRTUAL:
diff --git a/lib/librte_eal/common/eal_common_options.c b/lib/librte_eal/common/eal_common_options.c
index 1f459ac..6920088 100644
--- a/lib/librte_eal/common/eal_common_options.c
+++ b/lib/librte_eal/common/eal_common_options.c
@@ -889,7 +889,7 @@ eal_common_usage(void)
 	       "  -r RANKS            Force number of memory ranks (don't detect)\n"
 	       "  -b, --"OPT_PCI_BLACKLIST" Add a PCI device in black list.\n"
 	       "                      Prevent EAL from using this PCI device. The argument\n"
-	       "                      format is <domain:bus:devid.func>.\n"
+	       "                      format is <domain:bus:devid.func> or <name>.\n"
 	       "  -w, --"OPT_PCI_WHITELIST" Add a PCI device in white list.\n"
 	       "                      Only use the specified PCI devices. The argument format\n"
 	       "                      is <[domain:]bus:devid.func>. This option can be present\n"
diff --git a/lib/librte_eal/common/eal_common_pci.c b/lib/librte_eal/common/eal_common_pci.c
index dcfe947..288c8bd 100644
--- a/lib/librte_eal/common/eal_common_pci.c
+++ b/lib/librte_eal/common/eal_common_pci.c
@@ -93,8 +93,14 @@ static struct rte_devargs *pci_devargs_lookup(struct rte_pci_device *dev)
 		if (devargs->type != RTE_DEVTYPE_BLACKLISTED_PCI &&
 			devargs->type != RTE_DEVTYPE_WHITELISTED_PCI)
 			continue;
-		if (!rte_eal_compare_pci_addr(&dev->addr, &devargs->pci.addr))
-			return devargs;
+
+		if (devargs->pci.name[0] == '\0') {
+			if (!rte_eal_compare_pci_addr(&dev->addr, &devargs->pci.addr))
+				return devargs;
+		} else {
+			if (strcmp(dev->name, devargs->pci.name) == 0)
+				return devargs;
+		}
 	}
 	return NULL;
 }
diff --git a/lib/librte_eal/common/include/rte_devargs.h b/lib/librte_eal/common/include/rte_devargs.h
index 7084ae2..bc436ec 100644
--- a/lib/librte_eal/common/include/rte_devargs.h
+++ b/lib/librte_eal/common/include/rte_devargs.h
@@ -81,6 +81,8 @@ struct rte_devargs {
 		struct {
 			/** PCI location. */
 			struct rte_pci_addr addr;
+			/** Interface name. */
+			char name[32];
 		} pci;
 		/** Used if type is RTE_DEVTYPE_VIRTUAL. */
 		struct {
diff --git a/lib/librte_eal/common/include/rte_pci.h b/lib/librte_eal/common/include/rte_pci.h
index 83e3c28..852c149 100644
--- a/lib/librte_eal/common/include/rte_pci.h
+++ b/lib/librte_eal/common/include/rte_pci.h
@@ -161,6 +161,7 @@ struct rte_pci_device {
 	struct rte_pci_resource mem_resource[PCI_MAX_RESOURCE];   /**< PCI Memory Resource */
 	struct rte_intr_handle intr_handle;     /**< Interrupt handle */
 	struct rte_pci_driver *driver;          /**< Associated driver */
+	char name[32];				/**< Interface name (if any) */
 	uint16_t max_vfs;                       /**< sriov enable if not zero */
 	int numa_node;                          /**< NUMA node connection */
 	struct rte_devargs *devargs;            /**< Device user arguments */
diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
index bc5b5be..befb71f 100644
--- a/lib/librte_eal/linuxapp/eal/eal_pci.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
@@ -260,6 +260,8 @@ pci_scan_one(const char *dirname, uint16_t domain, uint8_t bus,
 	unsigned long tmp;
 	struct rte_pci_device *dev;
 	char driver[PATH_MAX];
+	struct dirent *e;
+	DIR *dir;
 	int ret;
 
 	dev = malloc(sizeof(*dev));
@@ -352,6 +354,19 @@ pci_scan_one(const char *dirname, uint16_t domain, uint8_t bus,
 		return -1;
 	}
 
+	/* get network interface name */
+	snprintf(filename, sizeof(filename), "%s/net", dirname);
+	dir = opendir(filename);
+	if (dir) {
+		while ((e = readdir(dir)) != NULL) {
+			if (e->d_name[0] == '.')
+				continue;
+
+			strncpy(dev->name, e->d_name, sizeof(dev->name));
+		}
+		closedir(dir);
+	}
+
 	if (!ret) {
 		if (!strcmp(driver, "vfio-pci"))
 			dev->kdrv = RTE_KDRV_VFIO;
-- 
2.1.0