diff options
| -rw-r--r-- | fs/xfs/scrub/bmap.c | 101 |
1 files changed, 79 insertions, 22 deletions
diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c index 1487aaf3d95f..8175e8c17c14 100644 --- a/fs/xfs/scrub/bmap.c +++ b/fs/xfs/scrub/bmap.c @@ -639,6 +639,82 @@ xchk_bmap_check_ag_rmaps( } /* + * Decide if we want to scan the reverse mappings to determine if the attr + * fork /really/ has zero space mappings. + */ +STATIC bool +xchk_bmap_check_empty_attrfork( + struct xfs_inode *ip) +{ + struct xfs_ifork *ifp = &ip->i_af; + + /* + * If the dinode repair found a bad attr fork, it will reset the fork + * to extents format with zero records and wait for the this scrubber + * to reconstruct the block mappings. If the fork is not in this + * state, then the fork cannot have been zapped. + */ + if (ifp->if_format != XFS_DINODE_FMT_EXTENTS || ifp->if_nextents != 0) + return false; + + /* + * Files can have an attr fork in EXTENTS format with zero records for + * several reasons: + * + * a) an attr set created a fork but ran out of space + * b) attr replace deleted an old attr but failed during the set step + * c) the data fork was in btree format when all attrs were deleted, so + * the fork was left in place + * d) the inode repair code zapped the fork + * + * Only in case (d) do we want to scan the rmapbt to see if we need to + * rebuild the attr fork. The fork zap code clears all DAC permission + * bits and zeroes the uid and gid, so avoid the scan if any of those + * three conditions are not met. + */ + if ((VFS_I(ip)->i_mode & 0777) != 0) + return false; + if (!uid_eq(VFS_I(ip)->i_uid, GLOBAL_ROOT_UID)) + return false; + if (!gid_eq(VFS_I(ip)->i_gid, GLOBAL_ROOT_GID)) + return false; + + return true; +} + +/* + * Decide if we want to scan the reverse mappings to determine if the data + * fork /really/ has zero space mappings. + */ +STATIC bool +xchk_bmap_check_empty_datafork( + struct xfs_inode *ip) +{ + struct xfs_ifork *ifp = &ip->i_df; + + /* Don't support realtime rmap checks yet. */ + if (XFS_IS_REALTIME_INODE(ip)) + return false; + + /* + * If the dinode repair found a bad data fork, it will reset the fork + * to extents format with zero records and wait for the this scrubber + * to reconstruct the block mappings. If the fork is not in this + * state, then the fork cannot have been zapped. + */ + if (ifp->if_format != XFS_DINODE_FMT_EXTENTS || ifp->if_nextents != 0) + return false; + + /* + * If we encounter an empty data fork along with evidence that the fork + * might not really be empty, we need to scan the reverse mappings to + * decide if we're going to rebuild the fork. Data forks with nonzero + * file size are scanned. + */ + return i_size_read(VFS_I(ip)) != 0; +} + +/* * Decide if we want to walk every rmap btree in the fs to make sure that each * rmap for this file fork has corresponding bmbt entries. */ @@ -647,7 +723,6 @@ xchk_bmap_want_check_rmaps( struct xchk_bmap_info *info) { struct xfs_scrub *sc = info->sc; - struct xfs_ifork *ifp; if (!xfs_has_rmapbt(sc->mp)) return false; @@ -656,28 +731,10 @@ xchk_bmap_want_check_rmaps( if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) return false; - /* Don't support realtime rmap checks yet. */ - if (info->is_rt) - return false; - - /* - * The inode repair code zaps broken inode forks by resetting them back - * to EXTENTS format and zero extent records. If we encounter a fork - * in this state along with evidence that the fork isn't supposed to be - * empty, we need to scan the reverse mappings to decide if we're going - * to rebuild the fork. Data forks with nonzero file size are scanned. - * xattr forks are never empty of content, so they are always scanned. - */ - ifp = xfs_ifork_ptr(sc->ip, info->whichfork); - if (ifp->if_format == XFS_DINODE_FMT_EXTENTS && ifp->if_nextents == 0) { - if (info->whichfork == XFS_DATA_FORK && - i_size_read(VFS_I(sc->ip)) == 0) - return false; - - return true; - } + if (info->whichfork == XFS_ATTR_FORK) + return xchk_bmap_check_empty_attrfork(sc->ip); - return false; + return xchk_bmap_check_empty_datafork(sc->ip); } /* Make sure each rmap has a corresponding bmbt entry. */ |