[PATCH 4/9] pci: rework sysfs parsing for driver

[David Marchand <david.marchand@6wind.com>]

There is no use for pci_get_kernel_driver_by_path() apart recognising
kernel driver and fill kdrv field.
If driver parsing fails, report "none" driver rather than "unknown".

Signed-off-by: David Marchand <david.marchand@6wind.com>
---
 lib/librte_eal/linuxapp/eal/eal_pci.c | 48 ++++++++++++++---------------------
 1 file changed, 19 insertions(+), 29 deletions(-)

diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
index 7bec30f..00fdee7 100644
--- a/lib/librte_eal/linuxapp/eal/eal_pci.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
@@ -94,32 +94,37 @@ error:
 }
 
 static int
-pci_get_kernel_driver_by_path(const char *filename, char *dri_name)
+pci_parse_sysfs_driver(const char *filename, struct rte_pci_device *dev)
 {
 	int count;
 	char path[PATH_MAX];
 	char *name;
 
-	if (!filename || !dri_name)
-		return -1;
-
 	count = readlink(filename, path, PATH_MAX);
 	if (count >= PATH_MAX)
 		return -1;
 
-	/* For device does not have a driver */
-	if (count < 0)
-		return 1;
+	dev->kdrv = RTE_KDRV_NONE;
 
-	path[count] = '\0';
+	if (count > 0) {
+		dev->kdrv = RTE_KDRV_UNKNOWN;
 
-	name = strrchr(path, '/');
-	if (name) {
-		strncpy(dri_name, name + 1, strlen(name + 1) + 1);
-		return 0;
+		path[count] = '\0';
+		name = strrchr(path, '/');
+		if (name) {
+			name[0] = '\0';
+			name++;
+		}
+
+		if (!strcmp(name, "vfio-pci"))
+			dev->kdrv = RTE_KDRV_VFIO;
+		else if (!strcmp(name, "igb_uio"))
+			dev->kdrv = RTE_KDRV_IGB_UIO;
+		else if (!strcmp(name, "uio_pci_generic"))
+			dev->kdrv = RTE_KDRV_UIO_GENERIC;
 	}
 
-	return -1;
+	return 0;
 }
 
 /* Map pci device */
@@ -260,8 +265,6 @@ pci_scan_one(const char *dirname, uint16_t domain, uint8_t bus,
 	unsigned long tmp;
 	struct rte_pci_device *dev;
 	struct rte_pci_device *dev2;
-	char driver[PATH_MAX];
-	int ret;
 
 	dev = malloc(sizeof(*dev));
 	if (dev == NULL)
@@ -341,25 +344,12 @@ pci_scan_one(const char *dirname, uint16_t domain, uint8_t bus,
 
 	/* parse driver */
 	snprintf(filename, sizeof(filename), "%s/driver", dirname);
-	ret = pci_get_kernel_driver_by_path(filename, driver);
-	if (ret < 0) {
+	if (pci_parse_sysfs_driver(filename, dev) < 0) {
 		RTE_LOG(ERR, EAL, "Fail to get kernel driver\n");
 		free(dev);
 		return -1;
 	}
 
-	if (!ret) {
-		if (!strcmp(driver, "vfio-pci"))
-			dev->kdrv = RTE_KDRV_VFIO;
-		else if (!strcmp(driver, "igb_uio"))
-			dev->kdrv = RTE_KDRV_IGB_UIO;
-		else if (!strcmp(driver, "uio_pci_generic"))
-			dev->kdrv = RTE_KDRV_UIO_GENERIC;
-		else
-			dev->kdrv = RTE_KDRV_UNKNOWN;
-	} else
-		dev->kdrv = RTE_KDRV_UNKNOWN;
-
 	dev2 = pci_find_device(&dev->addr);
 	if (!dev2)
 		pci_add_device(dev);
-- 
1.9.1