This is a note to let you know that I've just added the patch titled
xfs: rework collapse range into an atomic operation
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xfs-rework-collapse-range-into-an-atomic-operation.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Wed Oct 26 04:49:40 PM CEST 2022
From: Chandan Babu R <chandan.babu@xxxxxxxxxx>
Date: Wed, 26 Oct 2022 11:58:20 +0530
Subject: xfs: rework collapse range into an atomic operation
To: gregkh@xxxxxxxxxxxxxxxxxxx
Cc: sashal@xxxxxxxxxx, mcgrof@xxxxxxxxxx, linux-xfs@xxxxxxxxxxxxxxx, stable@xxxxxxxxxxxxxxx, djwong@xxxxxxxxxx, chandan.babu@xxxxxxxxxx, amir73il@xxxxxxxxx, leah.rumancik@xxxxxxxxx
Message-ID: <20221026062843.927600-4-chandan.babu@xxxxxxxxxx>
From: Brian Foster <bfoster@xxxxxxxxxx>
commit 211683b21de959a647de74faedfdd8a5d189327e upstream.
The collapse range operation uses a unique transaction and ilock
cycle for the hole punch and each extent shift iteration of the
overall operation. While the hole punch is safe as a separate
operation due to the iolock, cycling the ilock after each extent
shift is risky w.r.t. concurrent operations, similar to insert range.
To avoid this problem, make collapse range atomic with respect to
ilock. Hold the ilock across the entire operation, replace the
individual transactions with a single rolling transaction sequence
and finish dfops on each iteration to perform pending frees and roll
the transaction. Remove the unnecessary quota reservation as
collapse range can only ever merge extents (and thus remove extent
records and potentially free bmap blocks). The dfops call
automatically relogs the inode to keep it moving in the log. This
guarantees that nothing else can change the extent mapping of an
inode while a collapse range operation is in progress.
Signed-off-by: Brian Foster <bfoster@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Acked-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Signed-off-by: Chandan Babu R <chandan.babu@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/xfs/xfs_bmap_util.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1237,7 +1237,6 @@ xfs_collapse_file_space(
int error;
xfs_fileoff_t next_fsb = XFS_B_TO_FSB(mp, offset + len);
xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len);
- uint resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
bool done = false;
ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
@@ -1253,32 +1252,34 @@ xfs_collapse_file_space(
if (error)
return error;
- while (!error && !done) {
- error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0,
- &tp);
- if (error)
- break;
+ error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp);
+ if (error)
+ return error;
- xfs_ilock(ip, XFS_ILOCK_EXCL);
- error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot,
- ip->i_gdquot, ip->i_pdquot, resblks, 0,
- XFS_QMOPT_RES_REGBLKS);
- if (error)
- goto out_trans_cancel;
- xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
+ xfs_ilock(ip, XFS_ILOCK_EXCL);
+ xfs_trans_ijoin(tp, ip, 0);
+ while (!done) {
error = xfs_bmap_collapse_extents(tp, ip, &next_fsb, shift_fsb,
&done);
if (error)
goto out_trans_cancel;
+ if (done)
+ break;
- error = xfs_trans_commit(tp);
+ /* finish any deferred frees and roll the transaction */
+ error = xfs_defer_finish(&tp);
+ if (error)
+ goto out_trans_cancel;
}
+ error = xfs_trans_commit(tp);
+ xfs_iunlock(ip, XFS_ILOCK_EXCL);
return error;
out_trans_cancel:
xfs_trans_cancel(tp);
+ xfs_iunlock(ip, XFS_ILOCK_EXCL);
return error;
}
Patches currently in stable-queue which might be from chandan.babu@xxxxxxxxxx are
queue-5.4/xfs-check-owner-of-dir3-blocks.patch
queue-5.4/xfs-throttle-commits-on-delayed-background-cil-push.patch
queue-5.4/xfs-factor-common-ail-item-deletion-code.patch
queue-5.4/xfs-remove-the-xfs_dq_logitem_t-typedef.patch
queue-5.4/xfs-fix-buffer-corruption-reporting-when-xfs_dir3_free_header_check-fails.patch
queue-5.4/xfs-xfs_buf_corruption_error-should-take-__this_address.patch
queue-5.4/xfs-open-code-insert-range-extent-split-helper.patch
queue-5.4/xfs-don-t-write-a-corrupt-unmount-record-to-force-summary-counter-recalc.patch
queue-5.4/xfs-check-owner-of-dir3-data-blocks.patch
queue-5.4/xfs-factor-out-quotaoff-intent-ail-removal-and-memory-free.patch
queue-5.4/xfs-trylock-underlying-buffer-on-dquot-flush.patch
queue-5.4/xfs-remove-the-xfs_disk_dquot_t-and-xfs_dquot_t.patch
queue-5.4/xfs-add-a-function-to-deal-with-corrupt-buffers-post-verifiers.patch
queue-5.4/xfs-fix-use-after-free-on-cil-context-on-shutdown.patch
queue-5.4/xfs-tail-updates-only-need-to-occur-when-lsn-changes.patch
queue-5.4/xfs-use-scnprintf-for-avoiding-potential-buffer-overflow.patch
queue-5.4/xfs-move-inode-flush-to-the-sync-workqueue.patch
queue-5.4/xfs-lower-cil-flush-limit-for-large-logs.patch
queue-5.4/xfs-rework-collapse-range-into-an-atomic-operation.patch
queue-5.4/xfs-remove-the-xfs_qoff_logitem_t-typedef.patch
queue-5.4/xfs-fix-unmount-hang-and-memory-leak-on-shutdown-during-quotaoff.patch
queue-5.4/xfs-preserve-default-grace-interval-during-quotacheck.patch
queue-5.4/xfs-replace-function-declaration-by-actual-definition.patch
queue-5.4/xfs-rework-insert-range-into-an-atomic-operation.patch
queue-5.4/xfs-factor-out-a-new-xfs_log_force_inode-helper.patch
queue-5.4/xfs-reflink-should-force-the-log-out-if-mounted-with-wsync.patch
