diff options
| -rw-r--r-- | fs/xfs/xfs_dfrag.c | 106 |
1 files changed, 90 insertions, 16 deletions
diff --git a/fs/xfs/xfs_dfrag.c b/fs/xfs/xfs_dfrag.c index d1483a4f71b8..84ca1cf16a1e 100644 --- a/fs/xfs/xfs_dfrag.c +++ b/fs/xfs/xfs_dfrag.c @@ -114,10 +114,82 @@ xfs_swapext( return error; } +/* + * We need to check that the format of the data fork in the temporary inode is + * valid for the target inode before doing the swap. This is not a problem with + * attr1 because of the fixed fork offset, but attr2 has a dynamically sized + * data fork depending on the space the attribute fork is taking so we can get + * invalid formats on the target inode. + * + * E.g. target has space for 7 extents in extent format, temp inode only has + * space for 6. If we defragment down to 7 extents, then the tmp format is a + * btree, but when swapped it needs to be in extent format. Hence we can't just + * blindly swap data forks on attr2 filesystems. + * + * Note that we check the swap in both directions so that we don't end up with + * a corrupt temporary inode, either. + * + * Note that fixing the way xfs_fsr sets up the attribute fork in the source + * inode will prevent this situation from occurring, so all we do here is + * reject and log the attempt. basically we are putting the responsibility on + * userspace to get this right. + */ +static int +xfs_swap_extents_check_format( + xfs_inode_t *ip, /* target inode */ + xfs_inode_t *tip) /* tmp inode */ +{ + + /* Should never get a local format */ + if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL || + tip->i_d.di_format == XFS_DINODE_FMT_LOCAL) + return EINVAL; + + /* + * if the target inode has less extents that then temporary inode then + * why did userspace call us? + */ + if (ip->i_d.di_nextents < tip->i_d.di_nextents) + return EINVAL; + + /* + * if the target inode is in extent form and the temp inode is in btree + * form then we will end up with the target inode in the wrong format + * as we already know there are less extents in the temp inode. + */ + if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS && + tip->i_d.di_format == XFS_DINODE_FMT_BTREE) + return EINVAL; + + /* Check temp in extent form to max in target */ + if (tip->i_d.di_format == XFS_DINODE_FMT_EXTENTS && + XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK) > ip->i_df.if_ext_max) + return EINVAL; + + /* Check target in extent form to max in temp */ + if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS && + XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK) > tip->i_df.if_ext_max) + return EINVAL; + + /* Check root block of temp in btree form to max in target */ + if (tip->i_d.di_format == XFS_DINODE_FMT_BTREE && + XFS_IFORK_BOFF(ip) && + tip->i_df.if_broot_bytes > XFS_IFORK_BOFF(ip)) + return EINVAL; + + /* Check root block of target in btree form to max in temp */ + if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE && + XFS_IFORK_BOFF(tip) && + ip->i_df.if_broot_bytes > XFS_IFORK_BOFF(tip)) + return EINVAL; + + return 0; +} + int xfs_swap_extents( - xfs_inode_t *ip, - xfs_inode_t *tip, + xfs_inode_t *ip, /* target inode */ + xfs_inode_t *tip, /* tmp inode */ xfs_swapext_t *sxp) { xfs_mount_t *mp; @@ -161,13 +233,6 @@ xfs_swap_extents( goto out_unlock; } - /* Should never get a local format */ - if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL || - tip->i_d.di_format == XFS_DINODE_FMT_LOCAL) { - error = XFS_ERROR(EINVAL); - goto out_unlock; - } - if (VN_CACHED(VFS_I(tip)) != 0) { error = xfs_flushinval_pages(tip, 0, -1, FI_REMAPF_LOCKED); @@ -189,13 +254,12 @@ xfs_swap_extents( goto out_unlock; } - /* - * If the target has extended attributes, the tmp file - * must also in order to ensure the correct data fork - * format. - */ - if ( XFS_IFORK_Q(ip) != XFS_IFORK_Q(tip) ) { - error = XFS_ERROR(EINVAL); + /* check inode formats now that data is flushed */ + error = xfs_swap_extents_check_format(ip, tip); + if (error) { + xfs_fs_cmn_err(CE_NOTE, mp, + "%s: inode 0x%llx format is incompatible for exchanging.", + __FILE__, ip->i_ino); goto out_unlock; } @@ -276,6 +340,16 @@ xfs_swap_extents( *tifp = *tempifp; /* struct copy */ /* + * Fix the in-memory data fork values that are dependent on the fork + * offset in the inode. We can't assume they remain the same as attr2 + * has dynamic fork offsets. + */ + ifp->if_ext_max = XFS_IFORK_SIZE(ip, XFS_DATA_FORK) / + (uint)sizeof(xfs_bmbt_rec_t); + tifp->if_ext_max = XFS_IFORK_SIZE(tip, XFS_DATA_FORK) / + (uint)sizeof(xfs_bmbt_rec_t); + + /* * Fix the on-disk inode values */ tmp = (__uint64_t)ip->i_d.di_nblocks; |