NAME
----
-btrfs-check - check or repair an unmounted btrfs filesystem
+btrfs-check - check or repair a btrfs filesystem
SYNOPSIS
--------
-----------
The filesystem checker is used to verify structural integrity of a filesystem
-and attempt to repair it if requested. The filesystem must be unmounted.
+and attempt to repair it if requested. It is recommended to unmount the
+filesystem prior to running the check, but it is possible to start checking a
+mounted filesystem (see '--force').
By default, *btrfs check* will not modify the device but you can reaffirm that
by the option '--readonly'.
NOTE: 'lowmem' mode does not work with '--repair' yet, and is still considered
experimental.
+--force::
+allow to work on a mounted filesystem. Note that this should work fine on a
+quiescent or read-only mounted filesystem but may crash if the device is
+changed externally, eg. by the kernel module. Repair without mount checks is
+not supported right now.
+
EXIT STATUS
-----------
*btrfs check* returns a zero exit status if it succeeds. Non zero is
"",
"-s|--super <superblock> use this superblock copy",
"-b|--backup use the first valid backup root copy",
+ "--force skip mount checks, repair is not possible",
"--repair try to repair the filesystem",
"--readonly run in read-only mode (default)",
"--init-csum-tree create a new CRC tree",
u64 tree_root_bytenr = 0;
u64 chunk_root_bytenr = 0;
char uuidbuf[BTRFS_UUID_UNPARSED_SIZE];
- int ret;
+ int ret = 0;
int err = 0;
u64 num;
int init_csum_tree = 0;
int qgroup_report = 0;
int qgroups_repaired = 0;
unsigned ctree_flags = OPEN_CTREE_EXCLUSIVE;
+ int force = 0;
while(1) {
int c;
enum { GETOPT_VAL_REPAIR = 257, GETOPT_VAL_INIT_CSUM,
GETOPT_VAL_INIT_EXTENT, GETOPT_VAL_CHECK_CSUM,
GETOPT_VAL_READONLY, GETOPT_VAL_CHUNK_TREE,
- GETOPT_VAL_MODE, GETOPT_VAL_CLEAR_SPACE_CACHE };
+ GETOPT_VAL_MODE, GETOPT_VAL_CLEAR_SPACE_CACHE,
+ GETOPT_VAL_FORCE };
static const struct option long_options[] = {
{ "super", required_argument, NULL, 's' },
{ "repair", no_argument, NULL, GETOPT_VAL_REPAIR },
GETOPT_VAL_MODE },
{ "clear-space-cache", required_argument, NULL,
GETOPT_VAL_CLEAR_SPACE_CACHE},
+ { "force", no_argument, NULL, GETOPT_VAL_FORCE },
{ NULL, 0, NULL, 0}
};
}
ctree_flags |= OPEN_CTREE_WRITES;
break;
+ case GETOPT_VAL_FORCE:
+ force = 1;
+ break;
}
}
radix_tree_init();
cache_tree_init(&root_cache);
- if((ret = check_mounted(argv[optind])) < 0) {
- error("could not check mount status: %s", strerror(-ret));
- err |= !!ret;
- goto err_out;
- } else if(ret) {
- error("%s is currently mounted, aborting", argv[optind]);
- ret = -EBUSY;
- err |= !!ret;
- goto err_out;
+ ret = check_mounted(argv[optind]);
+ if (!force) {
+ if (ret < 0) {
+ error("could not check mount status: %s",
+ strerror(-ret));
+ err |= !!ret;
+ goto err_out;
+ } else if (ret) {
+ error(
+"%s is currently mounted, use --force if you really intend to check the filesystem",
+ argv[optind]);
+ ret = -EBUSY;
+ err |= !!ret;
+ goto err_out;
+ }
+ } else {
+ if (repair) {
+ error("repair and --force is not yet supported");
+ ret = 1;
+ err |= !!ret;
+ goto err_out;
+ }
+ if (ret < 0) {
+ warning(
+"cannot check mount status of %s, the filesystem could be mounted, continuing because of --force",
+ argv[optind]);
+ } else if (ret) {
+ warning(
+ "filesystem mounted, continuing because of --force");
+ }
}
/* only allow partial opening under repair mode */