Merge pull request #302 from bergwolf/scsi-ready

retry blockdev mount

Author: gao-feng

src/container.c

@@ -134,7 +134,7 @@ static int container_setup_volume(struct hyper_container *container)
 			if (!strcmp(vol->fstype, "xfs"))
 				options = "nouuid";
 
-			if (mount(dev, path, vol->fstype, 0, options) < 0) {
+			if (hyper_mount_blockdev(dev, path, vol->fstype, options) < 0) {
 				perror("mount volume device failed");
 				return -1;
 			}
@@ -588,7 +588,7 @@ static int hyper_setup_container_rootfs(void *data)
 		if (!strncmp(container->fstype, "xfs", strlen("xfs")))
 			options = "nouuid";
 
-		if (mount(dev, root, container->fstype, 0, options) < 0) {
+		if (hyper_mount_blockdev(dev, root, container->fstype, options) < 0) {
 			perror("mount device failed");
 			goto fail;
 		}

src/util.c

@@ -102,15 +102,22 @@ int hyper_find_sd(char *addr, char **dev)
 	struct dirent **list;
 	struct dirent *dir;
 	char path[512];
-	int i, num;
+	int i, num, retry = 5;
 
 	sprintf(path, "/sys/class/scsi_disk/0:0:%s/device/block/", addr);
 	fprintf(stdout, "orig dev %s, scan path %s\n", *dev, path);
 
-	num = scandir(path, &list, NULL, NULL);
-	if (num < 0) {
-		perror("scan path failed");
-		return -1;
+	for (i = 0;; i++) {
+		num = scandir(path, &list, NULL, NULL);
+		if (num < 0) {
+			if (errno != ENOENT || i >= retry) {
+				perror("scan path failed");
+				return -1;
+			}
+			usleep(20000);
+			continue;
+		}
+		break;
 	}
 
 	for (i = 0; i < num; i++) {
@@ -913,3 +920,21 @@ int hyper_eventfd_send(int fd, int64_t type)
 
 	return 0;
 }
+
+/* block device might not be present when we call mount. Sleep a bit in such case */
+int hyper_mount_blockdev(const char *dev, const char *root, const char *fstype, const char *options)
+{
+	int i, retry = 5;
+
+	for (i = 0; i < retry; i++) {
+		if (mount(dev, root, fstype, 0, options) < 0) {
+			if (errno != ENOENT)
+				return -1;
+			usleep(20000);
+			continue;
+		}
+		return 0;
+	}
+
+	return -1;
+}

src/util.h

@@ -50,4 +50,5 @@ ssize_t nonblock_read(int fd, void *buf, size_t count);
 int hyper_mount_nfs(char *server, char *mountpoint);
 int64_t hyper_eventfd_recv(int fd);
 int hyper_eventfd_send(int fd, int64_t type);
+int hyper_mount_blockdev(const char *dev, const char *root, const char *fstype, const char *options);
 #endif