Btrfs: Add mount -o degraded to allow mounts to continue with missing devices
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 020e5a8..273a5b5 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -65,11 +65,13 @@
}
enum {
- Opt_subvol, Opt_nodatasum, Opt_nodatacow, Opt_max_extent,
- Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd, Opt_err,
+ Opt_degraded, Opt_subvol, Opt_nodatasum, Opt_nodatacow,
+ Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier,
+ Opt_ssd, Opt_err,
};
static match_table_t tokens = {
+ {Opt_degraded, "degraded"},
{Opt_subvol, "subvol=%s"},
{Opt_nodatasum, "nodatasum"},
{Opt_nodatacow, "nodatacow"},
@@ -106,9 +108,8 @@
return res;
}
-static int parse_options (char * options,
- struct btrfs_root *root,
- char **subvol_name)
+int btrfs_parse_options(char *options, struct btrfs_root *root,
+ char **subvol_name)
{
char * p;
struct btrfs_fs_info *info = NULL;
@@ -135,6 +136,12 @@
token = match_token(p, tokens, args);
switch (token) {
+ case Opt_degraded:
+ if (info) {
+ printk("btrfs: allowing degraded mounts\n");
+ btrfs_set_opt(info->mount_opt, DEGRADED);
+ }
+ break;
case Opt_subvol:
if (subvol_name) {
*subvol_name = match_strdup(&args[0]);
@@ -234,7 +241,7 @@
sb->s_xattr = btrfs_xattr_handlers;
sb->s_time_gran = 1;
- tree_root = open_ctree(sb, fs_devices);
+ tree_root = open_ctree(sb, fs_devices, (char *)data);
if (IS_ERR(tree_root)) {
printk("btrfs: open_ctree failed\n");
@@ -267,8 +274,6 @@
goto fail_close;
}
- parse_options((char *)data, tree_root, NULL);
-
/* this does the super kobj at the same time */
err = btrfs_sysfs_add_super(tree_root->fs_info);
if (err)
@@ -341,7 +346,7 @@
if (error)
return error;
- bdev = fs_devices->lowest_bdev;
+ bdev = fs_devices->latest_bdev;
btrfs_lock_volumes();
s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices);
btrfs_unlock_volumes();
@@ -411,7 +416,7 @@
int ret;
char *subvol_name = NULL;
- parse_options((char *)data, NULL, &subvol_name);
+ btrfs_parse_options((char *)data, NULL, &subvol_name);
ret = btrfs_get_sb_bdev(fs_type, flags, dev_name, data, mnt,
subvol_name ? subvol_name : "default");
if (subvol_name)