pci: add option --create-uio-dev to run without hotplug

[dpdk.git] / lib / librte_eal / linuxapp / eal / eal_pci.c

diff --git a/lib/librte_eal/linuxapp/eal/eal_pci.c b/lib/librte_eal/linuxapp/eal/eal_pci.c
index e6216c5..5fa466e 100644 (file)
--- a/lib/librte_eal/linuxapp/eal/eal_pci.c
+++ b/lib/librte_eal/linuxapp/eal/eal_pci.c
@@ -460,6 +460,47 @@ pci_uio_map_secondary(struct rte_pci_device *dev)
        return -1;
 }
 
+static int pci_mknod_uio_dev(const char *sysfs_uio_path, unsigned uio_num)
+{
+       FILE *f;
+       char filename[PATH_MAX];
+       int ret;
+       unsigned major, minor;
+       dev_t dev;
+
+       /* get the name of the sysfs file that contains the major and minor
+        * of the uio device and read its content */
+       rte_snprintf(filename, sizeof(filename), "%s/dev", sysfs_uio_path);
+
+       f = fopen(filename, "r");
+       if (f == NULL) {
+               RTE_LOG(ERR, EAL, "%s(): cannot open sysfs to get major:minor\n",
+                       __func__);
+               return -1;
+       }
+
+       ret = fscanf(f, "%d:%d", &major, &minor);
+       if (ret != 2) {
+               RTE_LOG(ERR, EAL, "%s(): cannot parse sysfs to get major:minor\n",
+                       __func__);
+               fclose(f);
+               return -1;
+       }
+       fclose(f);
+
+       /* create the char device "mknod /dev/uioX c major minor" */
+       rte_snprintf(filename, sizeof(filename), "/dev/uio%u", uio_num);
+       dev = makedev(major, minor);
+       ret = mknod(filename, S_IFCHR | S_IRUSR | S_IWUSR, dev);
+       if (f == NULL) {
+               RTE_LOG(ERR, EAL, "%s(): mknod() failed %s\n",
+                       __func__, strerror(errno));
+               return -1;
+       }
+
+       return ret;
+}
+
 /*
  * Return the uioX char device used for a pci device. On success, return
  * the UIO number and fill dstbuf string with the path of the device in
@@ -529,7 +570,11 @@ static int pci_get_uio_dev(struct rte_pci_device *dev, char *dstbuf,
        if (e == NULL)
                return -1;
 
-       return 0;
+       /* create uio device if we've been asked to */
+       if (internal_config.create_uio_dev && pci_mknod_uio_dev(dstbuf, uio_num) < 0)
+               RTE_LOG(WARNING, EAL, "Cannot create /dev/uio%u\n", uio_num);
+
+       return uio_num;
 }
 
 /* map the PCI resource of a PCI device in virtual memory */