diff options
| author |   Eric Sandeen <sandeen@sandeen.net> | 2015-07-29 11:53:31 +1000 |
|---|---|---|
| committer |   Dave Chinner <david@fromorbit.com> | 2015-07-29 11:53:31 +1000 |
| commit | ce748eaa65f2e9392ba82726503c8d994ffd6393 (patch) | |
| tree | ff3ec811268e84efbcebbf4b24ec23ff3438c1c7 /fs/xfs/libxfs/xfs_alloc.c | |
| parent | Linux 4.2-rc2 (diff) | |
| download | linux-dev-ce748eaa65f2e9392ba82726503c8d994ffd6393.tar.xz linux-dev-ce748eaa65f2e9392ba82726503c8d994ffd6393.zip | |
xfs: create new metadata UUID field and incompat flag
This adds a new superblock field, sb_meta_uuid. If set, along with
a new incompat flag, the code will use that field on a V5 filesystem
to compare to metadata UUIDs, which allows us to change the user-
visible UUID at will. Userspace handles the setting and clearing
of the incompat flag as appropriate, as the UUID gets changed; i.e.
setting the user-visible UUID back to the original UUID (as stored in
the new field) will remove the incompatible feature flag.
If the incompat flag is not set, this copies the user-visible UUID into
into the meta_uuid slot in memory when the superblock is read from disk;
the meta_uuid field is not written back to disk in this case.
The remainder of this patch simply switches verifiers, initializers,
etc to use the new sb_meta_uuid field.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Diffstat (limited to 'fs/xfs/libxfs/xfs_alloc.c')
| -rw-r--r-- | fs/xfs/libxfs/xfs_alloc.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c index f9e9ffe6fb46..b7fc17ce8233 100644 --- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -464,7 +464,7 @@ xfs_agfl_verify( struct xfs_agfl *agfl = XFS_BUF_TO_AGFL(bp); int i; - if (!uuid_equal(&agfl->agfl_uuid, &mp->m_sb.sb_uuid)) + if (!uuid_equal(&agfl->agfl_uuid, &mp->m_sb.sb_meta_uuid)) return false; if (be32_to_cpu(agfl->agfl_magicnum) != XFS_AGFL_MAGIC) return false; @@ -2260,7 +2260,7 @@ xfs_agf_verify( struct xfs_agf *agf = XFS_BUF_TO_AGF(bp); if (xfs_sb_version_hascrc(&mp->m_sb) && - !uuid_equal(&agf->agf_uuid, &mp->m_sb.sb_uuid)) + !uuid_equal(&agf->agf_uuid, &mp->m_sb.sb_meta_uuid)) return false; if (!(agf->agf_magicnum == cpu_to_be32(XFS_AGF_MAGIC) && |