From 44e69c9af159e61d4f765ff4805dd5b55f241597 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 3 Nov 2024 20:19:27 -0800 Subject: [PATCH] xfs: use realtime EFI to free extents when rtgroups are enabled When rmap is enabled, XFS expects a certain order of operations, which is: 1) remove the file mapping, 2) remove the reverse mapping, and then 3) free the blocks. When reflink is enabled, XFS replaces (3) with a deferred refcount decrement operation that can schedule freeing the blocks if that was the last refcount. For realtime files, xfs_bmap_del_extent_real tries to do 1 and 3 in the same transaction, which will break both rmap and reflink unless we switch it to use realtime EFIs. Both rmap and reflink depend on the rtgroups feature, so let's turn on EFIs for all rtgroups filesystems. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig --- fs/xfs/libxfs/xfs_bmap.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index 482b4c0cd6b19..b15a43c18b0a5 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -5383,9 +5383,11 @@ xfs_bmap_del_extent_real( * If we need to, add to list of extents to delete. */ if (!(bflags & XFS_BMAPI_REMAP)) { + bool isrt = xfs_ifork_is_realtime(ip, whichfork); + if (xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK) { xfs_refcount_decrease_extent(tp, del); - } else if (xfs_ifork_is_realtime(ip, whichfork)) { + } else if (isrt && !xfs_has_rtgroups(mp)) { error = xfs_bmap_free_rtblocks(tp, del); } else { unsigned int efi_flags = 0; @@ -5394,6 +5396,19 @@ xfs_bmap_del_extent_real( del->br_state == XFS_EXT_UNWRITTEN) efi_flags |= XFS_FREE_EXTENT_SKIP_DISCARD; + /* + * Historically, we did not use EFIs to free realtime + * extents. However, when reverse mapping is enabled, + * we must maintain the same order of operations as the + * data device, which is: Remove the file mapping, + * remove the reverse mapping, and then free the + * blocks. Reflink for realtime volumes requires the + * same sort of ordering. Both features rely on + * rtgroups, so let's gate rt EFI usage on rtgroups. + */ + if (isrt) + efi_flags |= XFS_FREE_EXTENT_REALTIME; + error = xfs_free_extent_later(tp, del->br_startblock, del->br_blockcount, NULL, XFS_AG_RESV_NONE, efi_flags); -- 2.50.1