From: "Darrick J. Wong" djwong@kernel.org
[ Upstream commit a949a1c2a198e048630a8b0741a99b85a5d88136 ]
The external log device fsmap backend doesn't have an rmapbt to query, so it's wasteful to spend time initializing the rmap_irec objects. Worse yet, the log could (someday) be longer than 2^32 fsblocks, so using the rmap irec structure will result in integer overflows.
Fix this mess by computing the start address that we want from keys[0] directly, and use the daddr-based record filtering algorithm that we also use for rtbitmap queries.
Fixes: e89c041338ed ("xfs: implement the GETFSMAP ioctl") Signed-off-by: Darrick J. Wong djwong@kernel.org Reviewed-by: Dave Chinner dchinner@redhat.com Signed-off-by: Leah Rumancik leah.rumancik@gmail.com Acked-by: "Darrick J. Wong" djwong@kernel.org --- fs/xfs/xfs_fsmap.c | 30 ++++++++---------------------- 1 file changed, 8 insertions(+), 22 deletions(-)
diff --git a/fs/xfs/xfs_fsmap.c b/fs/xfs/xfs_fsmap.c index 202f162515bd..cdd806d80b7c 100644 --- a/fs/xfs/xfs_fsmap.c +++ b/fs/xfs/xfs_fsmap.c @@ -435,40 +435,26 @@ xfs_getfsmap_logdev( struct xfs_getfsmap_info *info) { struct xfs_mount *mp = tp->t_mountp; struct xfs_rmap_irec rmap; xfs_daddr_t rec_daddr, len_daddr; - xfs_fsblock_t start_fsb; - int error; + xfs_fsblock_t start_fsb, end_fsb; + uint64_t eofs;
- /* Set up search keys */ + eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks); + if (keys[0].fmr_physical >= eofs) + return 0; start_fsb = XFS_BB_TO_FSBT(mp, keys[0].fmr_physical + keys[0].fmr_length); - info->low.rm_startblock = XFS_BB_TO_FSBT(mp, keys[0].fmr_physical); - info->low.rm_offset = XFS_BB_TO_FSBT(mp, keys[0].fmr_offset); - error = xfs_fsmap_owner_to_rmap(&info->low, keys); - if (error) - return error; - info->low.rm_blockcount = 0; - xfs_getfsmap_set_irec_flags(&info->low, &keys[0]); + end_fsb = XFS_BB_TO_FSB(mp, min(eofs - 1, keys[1].fmr_physical));
/* Adjust the low key if we are continuing from where we left off. */ if (keys[0].fmr_length > 0) info->low_daddr = XFS_FSB_TO_BB(mp, start_fsb);
- error = xfs_fsmap_owner_to_rmap(&info->high, keys + 1); - if (error) - return error; - info->high.rm_startblock = -1U; - info->high.rm_owner = ULLONG_MAX; - info->high.rm_offset = ULLONG_MAX; - info->high.rm_blockcount = 0; - info->high.rm_flags = XFS_RMAP_KEY_FLAGS | XFS_RMAP_REC_FLAGS; - info->missing_owner = XFS_FMR_OWN_FREE; - - trace_xfs_fsmap_low_key(mp, info->dev, NULLAGNUMBER, &info->low); - trace_xfs_fsmap_high_key(mp, info->dev, NULLAGNUMBER, &info->high); + trace_xfs_fsmap_low_key_linear(mp, info->dev, start_fsb); + trace_xfs_fsmap_high_key_linear(mp, info->dev, end_fsb);
if (start_fsb > 0) return 0;
/* Fabricate an rmap entry for the external log device. */