[PATCH 5.18 052/879] btrfs: zoned: finish block group when there are no more allocatable bytes left

[Greg Kroah-Hartman]

From: Naohiro Aota <naohiro.aota@xxxxxxx>

commit 8b8a53998caefebfe5c8da7a74c2b601caf5dd48 upstream.

Currently, btrfs_zone_finish_endio() finishes a block group only when the
written region reaches the end of the block group. We can also finish the
block group when no more allocation is possible.

Fixes: be1a1d7a5d24 ("btrfs: zoned: finish fully written block group")
CC: stable@xxxxxxxxxxxxxxx # 5.16+
Reviewed-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Signed-off-by: Naohiro Aota <naohiro.aota@xxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 fs/btrfs/zoned.c |   11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -2000,6 +2000,7 @@ void btrfs_zone_finish_endio(struct btrf
 	struct btrfs_block_group *block_group;
 	struct map_lookup *map;
 	struct btrfs_device *device;
+	u64 min_alloc_bytes;
 	u64 physical;
 
 	if (!btrfs_is_zoned(fs_info))
@@ -2008,7 +2009,15 @@ void btrfs_zone_finish_endio(struct btrf
 	block_group = btrfs_lookup_block_group(fs_info, logical);
 	ASSERT(block_group);
 
-	if (logical + length < block_group->start + block_group->zone_capacity)
+	/* No MIXED_BG on zoned btrfs. */
+	if (block_group->flags & BTRFS_BLOCK_GROUP_DATA)
+		min_alloc_bytes = fs_info->sectorsize;
+	else
+		min_alloc_bytes = fs_info->nodesize;
+
+	/* Bail out if we can allocate more data from this block group. */
+	if (logical + length + min_alloc_bytes <=
+	    block_group->start + block_group->zone_capacity)
 		goto out;
 
 	spin_lock(&block_group->lock);