diff options
| author | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2009-03-26 12:51:21 +0200 |
|---|---|---|
| committer | Artem Bityutskiy <Artem.Bityutskiy@nokia.com> | 2009-03-26 16:36:20 +0200 |
| commit | 963f0cf6d116d83c558a8efe9045c1c5ad7aed34 (patch) | |
| tree | 43937f0d742bfac7dfc1a00bae8f72e98dc87425 /fs/ubifs/super.c | |
| parent | fcabb3479e2b15abfd2d2ef5363295f16e98b2d7 (diff) | |
UBIFS: add R/O compatibility
Now UBIFS is supported by u-boot. If we ever decide to change the
media format, then people will have to upgrade their u-boots to
mount new format images. However, very often it is possible to
preserve R/O forward-compatibility, even though the write
forward-compatibility is not preserved.
This patch introduces a new super-block field which stores the
R/O compatibility version.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Acked-by: Adrian Hunter <Adrian.Hunter@nokia.com>
Diffstat (limited to 'fs/ubifs/super.c')
| -rw-r--r-- | fs/ubifs/super.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c index 372c7fb6653..302a2056422 100644 --- a/fs/ubifs/super.c +++ b/fs/ubifs/super.c @@ -1351,8 +1351,9 @@ static int mount_ubifs(struct ubifs_info *c) x = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes; ubifs_msg("journal size: %lld bytes (%lld KiB, %lld MiB, %d " "LEBs)", x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt); - ubifs_msg("media format: %d (latest is %d)", - c->fmt_version, UBIFS_FORMAT_VERSION); + ubifs_msg("media format: w%d/r%d (latest is w%d/r%d)", + c->fmt_version, c->ro_compat_version, + UBIFS_FORMAT_VERSION, UBIFS_RO_COMPAT_VERSION); ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr)); ubifs_msg("reserved for root: %llu bytes (%llu KiB)", c->report_rp_size, c->report_rp_size >> 10); @@ -1492,6 +1493,15 @@ static int ubifs_remount_rw(struct ubifs_info *c) { int err, lnum; + if (c->rw_incompat) { + ubifs_err("the file-system is not R/W-compatible"); + ubifs_msg("on-flash format version is w%d/r%d, but software " + "only supports up to version w%d/r%d", c->fmt_version, + c->ro_compat_version, UBIFS_FORMAT_VERSION, + UBIFS_RO_COMPAT_VERSION); + return -EROFS; + } + mutex_lock(&c->umount_mutex); dbg_save_space_info(c); c->remounting_rw = 1; |