diff options
Diffstat (limited to '')
| -rw-r--r-- | fs/xfs/libxfs/xfs_attr_remote.c | 37 |
1 files changed, 31 insertions, 6 deletions
diff --git a/fs/xfs/libxfs/xfs_attr_remote.c b/fs/xfs/libxfs/xfs_attr_remote.c index df1ab0569481..a266d05df146 100644 --- a/fs/xfs/libxfs/xfs_attr_remote.c +++ b/fs/xfs/libxfs/xfs_attr_remote.c @@ -26,6 +26,23 @@ #define ATTR_RMTVALUE_MAPSIZE 1 /* # of map entries at once */ /* + * Remote Attribute Values + * ======================= + * + * Remote extended attribute values are conceptually simple -- they're written + * to data blocks mapped by an inode's attribute fork, and they have an upper + * size limit of 64k. Setting a value does not involve the XFS log. + * + * However, on a v5 filesystem, maximally sized remote attr values require one + * block more than 64k worth of space to hold both the remote attribute value + * header (64 bytes). On a 4k block filesystem this results in a 68k buffer; + * on a 64k block filesystem, this would be a 128k buffer. Note that the log + * format can only handle a dirty buffer of XFS_MAX_BLOCKSIZE length (64k). + * Therefore, we /must/ ensure that remote attribute value buffers never touch + * the logging system and therefore never have a log item. + */ + +/* * Each contiguous block has a header, so it is not just a simple attribute * length to FSB conversion. */ @@ -401,17 +418,25 @@ xfs_attr_rmtval_get( (map[i].br_startblock != HOLESTARTBLOCK)); dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock); dblkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount); - error = xfs_trans_read_buf(mp, args->trans, - mp->m_ddev_targp, - dblkno, dblkcnt, 0, &bp, - &xfs_attr3_rmt_buf_ops); - if (error) + bp = xfs_buf_read(mp->m_ddev_targp, dblkno, dblkcnt, 0, + &xfs_attr3_rmt_buf_ops); + if (!bp) + return -ENOMEM; + error = bp->b_error; + if (error) { + xfs_buf_ioerror_alert(bp, __func__); + xfs_buf_relse(bp); + + /* bad CRC means corrupted metadata */ + if (error == -EFSBADCRC) + error = -EFSCORRUPTED; return error; + } error = xfs_attr_rmtval_copyout(mp, bp, args->dp->i_ino, &offset, &valuelen, &dst); - xfs_trans_brelse(args->trans, bp); + xfs_buf_relse(bp); if (error) return error; |