storage: prefix all btrfs paths

src/lxc/bdev/lxcbtrfs.c

@@ -191,11 +191,12 @@ int btrfs_detect(const char *path)
 int btrfs_mount(struct bdev *bdev)
 {
 	unsigned long mntflags;
-	char *mntdata;
+	char *mntdata, *src;
 	int ret;
 
 	if (strcmp(bdev->type, "btrfs"))
 		return -22;
+
 	if (!bdev->src || !bdev->dest)
 		return -22;
 
@@ -204,7 +205,9 @@ int btrfs_mount(struct bdev *bdev)
 		return -22;
 	}
 
-	ret = mount(bdev->src, bdev->dest, "bind", MS_BIND | MS_REC | mntflags, mntdata);
+	src = lxc_storage_get_path(bdev->src, "btrfs");
+
+	ret = mount(src, bdev->dest, "bind", MS_BIND | MS_REC | mntflags, mntdata);
 	free(mntdata);
 	return ret;
 }
@@ -213,8 +216,10 @@ int btrfs_umount(struct bdev *bdev)
 {
 	if (strcmp(bdev->type, "btrfs"))
 		return -22;
+
 	if (!bdev->src || !bdev->dest)
 		return -22;
+
 	return umount(bdev->dest);
 }
 
@@ -343,7 +348,9 @@ out:
 
 static int btrfs_snapshot_wrapper(void *data)
 {
+	char *src;
 	struct rsync_data_char *arg = data;
+
 	if (setgid(0) < 0) {
 		ERROR("Failed to setgid to 0");
 		return -1;
@@ -354,7 +361,10 @@ static int btrfs_snapshot_wrapper(void *data)
 		ERROR("Failed to setuid to 0");
 		return -1;
 	}
-	return btrfs_snapshot(arg->src, arg->dest);
+
+	src = lxc_storage_get_path(arg->src, "btrfs");
+
+	return btrfs_snapshot(src, arg->dest);
 }
 
 int btrfs_clonepaths(struct bdev *orig, struct bdev *new, const char *oldname,
@@ -362,6 +372,8 @@ int btrfs_clonepaths(struct bdev *orig, struct bdev *new, const char *oldname,
 		     const char *lxcpath, int snap, uint64_t newsize,
 		     struct lxc_conf *conf)
 {
+	char *src;
+
 	if (!orig->dest || !orig->src)
 		return -1;
 
@@ -372,21 +384,26 @@ int btrfs_clonepaths(struct bdev *orig, struct bdev *new, const char *oldname,
 				orig->type);
 			return -1;
 		}
-		len = strlen(lxcpath) + strlen(cname) + strlen("rootfs") + 3;
+
+		len = strlen(lxcpath) + strlen(cname) + strlen("rootfs") + 6 + 3;
 		new->src = malloc(len);
 		if (!new->src)
 			return -1;
-		ret = snprintf(new->src, len, "%s/%s/rootfs", lxcpath, cname);
+
+		ret = snprintf(new->src, len, "btrfs:%s/%s/rootfs", lxcpath, cname);
 		if (ret < 0 || ret >= len)
 			return -1;
 	} else {
-		// in case rootfs is in custom path, reuse it
-		if ((new->src = dir_new_path(orig->src, oldname, cname, oldpath, lxcpath)) == NULL)
+		/* In case rootfs is in custom path, reuse it. */
+		new->src = dir_new_path(orig->src, oldname, cname, oldpath, lxcpath);
+		if (!new->src)
 			return -1;
 
 	}
 
-	if ((new->dest = strdup(new->src)) == NULL)
+	src = lxc_storage_get_path(new->src, "btrfs");
+	new->dest = strdup(src);
+	if (!new->dest)
 		return -1;
 
 	if (orig->mntopts && (new->mntopts = strdup(orig->mntopts)) == NULL)
@@ -731,21 +748,39 @@ bool btrfs_try_remove_subvol(const char *path)
 {
 	if (!btrfs_detect(path))
 		return false;
+
 	return btrfs_recursive_destroy(path) == 0;
 }
 
 int btrfs_destroy(struct bdev *orig)
 {
-	return btrfs_recursive_destroy(orig->src);
+	char *src;
+
+	src = lxc_storage_get_path(orig->src, "btrfs");
+
+	return btrfs_recursive_destroy(src);
 }
 
 int btrfs_create(struct bdev *bdev, const char *dest, const char *n,
 		 struct bdev_specs *specs)
 {
-	bdev->src = strdup(dest);
+	int ret;
+	size_t len;
+
+	len = strlen(dest) + 1;
+	/* strlen("btrfs:") */
+	len += 6;
+	bdev->src = malloc(len);
+	if (!bdev->src)
+		return -1;
+
+	ret = snprintf(bdev->src, len, "btrfs:%s", dest);
+	if (ret < 0 || (size_t)ret >= len)
+		return -1;
+
 	bdev->dest = strdup(dest);
-	if (!bdev->src || !bdev->dest)
+	if (!bdev->dest)
 		return -1;
+
 	return btrfs_subvolume_create(bdev->dest);
 }
-