@@ -2909,13 +2909,14 @@ xfs_bmap_add_extent_hole_real(
ASSERT(!isnullstartblock(new->br_startblock));
ASSERT(!bma->cur ||
!(bma->cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
- ASSERT(whichfork != XFS_COW_FORK);
XFS_STATS_INC(mp, xs_add_exlist);
state = 0;
if (whichfork == XFS_ATTR_FORK)
state |= BMAP_ATTRFORK;
+ if (whichfork == XFS_COW_FORK)
+ state |= BMAP_COWFORK;
/*
* Check and set flags if this segment has a left neighbor.
@@ -391,62 +391,100 @@ __xfs_reflink_allocate_cow(
xfs_fileoff_t end_fsb)
{
struct xfs_mount *mp = ip->i_mount;
- struct xfs_bmbt_irec imap;
+ struct xfs_bmbt_irec imap, got;
struct xfs_defer_ops dfops;
struct xfs_trans *tp;
xfs_fsblock_t first_block;
- int nimaps = 1, error;
- bool shared;
+ int nimaps, error, lockmode;
+ bool shared, trimmed;
+ xfs_filblks_t resaligned;
+ xfs_extlen_t resblks;
+ xfs_extnum_t idx;
- xfs_defer_init(&dfops, &first_block);
+ resaligned = xfs_aligned_fsb_count(*offset_fsb, end_fsb - *offset_fsb,
+ xfs_get_cowextsz_hint(ip));
+ resblks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned);
- error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0,
- XFS_TRANS_RESERVE, &tp);
+ error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp);
if (error)
return error;
- xfs_ilock(ip, XFS_ILOCK_EXCL);
+ lockmode = XFS_ILOCK_EXCL;
+ xfs_ilock(ip, lockmode);
- /* Read extent from the source file. */
- nimaps = 1;
- error = xfs_bmapi_read(ip, *offset_fsb, end_fsb - *offset_fsb,
- &imap, &nimaps, 0);
- if (error)
- goto out_unlock;
- ASSERT(nimaps == 1);
+ /*
+ * Even if the extent is not shared we might have a preallocation for
+ * it in the COW fork. If so use it.
+ */
+ if (xfs_iext_lookup_extent(ip, ip->i_cowfp, *offset_fsb, &idx, &got) &&
+ got.br_startoff <= *offset_fsb) {
+ /* If we have a real allocation in the COW fork we're done. */
+ if (!isnullstartblock(got.br_startblock)) {
+ xfs_trim_extent(&got, *offset_fsb,
+ end_fsb - *offset_fsb);
+ *offset_fsb = got.br_startoff + got.br_blockcount;
+ goto out_trans_cancel;
+ }
+ } else {
+ nimaps = 1;
+ error = xfs_bmapi_read(ip, *offset_fsb, end_fsb - *offset_fsb,
+ &imap, &nimaps, 0);
+ if (error)
+ goto out_trans_cancel;
+ ASSERT(nimaps == 1);
+
+ /* Trim the mapping to the nearest shared extent boundary. */
+ error = xfs_reflink_trim_around_shared(ip, &imap, &shared,
+ &trimmed);
+ if (error)
+ goto out_trans_cancel;
+
+ if (!shared) {
+ *offset_fsb = imap.br_startoff + imap.br_blockcount;
+ goto out_trans_cancel;
+ }
- /* Make sure there's a CoW reservation for it. */
- error = xfs_reflink_reserve_cow(ip, &imap, &shared);
+ *offset_fsb = imap.br_startoff;
+ end_fsb = imap.br_startoff + imap.br_blockcount;
+ }
+
+ error = xfs_trans_reserve_quota_nblks(tp, ip, resblks, 0,
+ XFS_QMOPT_RES_REGBLKS);
if (error)
goto out_trans_cancel;
- if (!shared) {
- *offset_fsb = imap.br_startoff + imap.br_blockcount;
- goto out_trans_cancel;
- }
+ xfs_trans_ijoin(tp, ip, 0);
+
+ xfs_defer_init(&dfops, &first_block);
+ nimaps = 1;
/* Allocate the entire reservation as unwritten blocks. */
- xfs_trans_ijoin(tp, ip, 0);
- error = xfs_bmapi_write(tp, ip, imap.br_startoff, imap.br_blockcount,
+ error = xfs_bmapi_write(tp, ip, *offset_fsb, end_fsb - *offset_fsb,
XFS_BMAPI_COWFORK | XFS_BMAPI_PREALLOC, &first_block,
- XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK),
- &imap, &nimaps, &dfops);
+ resblks, &imap, &nimaps, &dfops);
if (error)
- goto out_trans_cancel;
+ goto out_bmap_cancel;
/* Finish up. */
error = xfs_defer_finish(&tp, &dfops, NULL);
if (error)
- goto out_trans_cancel;
+ goto out_bmap_cancel;
error = xfs_trans_commit(tp);
+ if (error)
+ goto out_unlock;
*offset_fsb = imap.br_startoff + imap.br_blockcount;
+
out_unlock:
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
+ xfs_iunlock(ip, lockmode);
return error;
-out_trans_cancel:
+
+out_bmap_cancel:
xfs_defer_cancel(&dfops);
+ xfs_trans_unreserve_quota_nblks(tp, ip, (long)resblks, 0,
+ XFS_QMOPT_RES_REGBLKS);
+out_trans_cancel:
xfs_trans_cancel(tp);
goto out_unlock;
}
When we allocate COW fork blocks for direct I/O writes we currently first create a delayed allocation, and then convert it to a real allocation once we've got the delayed one. As there is no good reason for that this patch instead makes use call xfs_bmapi_write from the COW allocation path. The only interesting bits are a few tweaks the low-level allocator to allow for this, most notably the need to remove the call to xfs_bmap_extsize_align for the cowextsize in xfs_bmap_btalloc - for the existing convert case it's a no-op, but for the direct allocation case it would blow up our block reservation way beyond what we reserved for the transaction. Signed-off-by: Christoph Hellwig <hch@lst.de> --- fs/xfs/libxfs/xfs_bmap.c | 3 +- fs/xfs/xfs_reflink.c | 94 +++++++++++++++++++++++++++++++++--------------- 2 files changed, 68 insertions(+), 29 deletions(-)