[PATCH 2/5] btrfs: zoned: don't clear dirty flag of extent buffer

[Johannes Thumshirn]

One a zoned filesystem, never clear the dirty flag of an extent buffer,
but instead mark it as cancelled.

On writeout, when encountering cancelled extent_buffers, zero them out.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
---
 fs/btrfs/disk-io.c   | 2 +-
 fs/btrfs/extent_io.c | 7 +++++--
 fs/btrfs/zoned.c     | 3 ++-
 3 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index ff6140e7eef7..f259bae1c3ee 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -255,7 +255,7 @@ blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio)
 		return BLK_STS_IOERR;
 
 	if (test_bit(EXTENT_BUFFER_CANCELLED, &eb->bflags)) {
-		WARN_ON_ONCE(found_start != 0);
+		memzero_extent_buffer(eb, 0, eb->len);
 		return BLK_STS_OK;
 	}
 
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 74f984885719..8bc5025ce278 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -3748,6 +3748,11 @@ void btrfs_clear_buffer_dirty(struct btrfs_trans_handle *trans,
 	if (trans && btrfs_header_generation(eb) != trans->transid)
 		return;
 
+	if (btrfs_is_zoned(fs_info)) {
+		set_bit(EXTENT_BUFFER_CANCELLED, &eb->bflags);
+		return;
+	}
+
 	if (!test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags))
 		return;
 
@@ -4139,8 +4144,6 @@ static void __write_extent_buffer(const struct extent_buffer *eb,
 	/* For unmapped (dummy) ebs, no need to check their uptodate status. */
 	const bool check_uptodate = !test_bit(EXTENT_BUFFER_UNMAPPED, &eb->bflags);
 
-	WARN_ON(test_bit(EXTENT_BUFFER_CANCELLED, &eb->bflags));
-
 	if (check_eb_range(eb, start, len))
 		return;
 
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 89cd1664efe1..117e041bdc7a 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -1722,7 +1722,8 @@ void btrfs_redirty_list_add(struct btrfs_transaction *trans,
 	    btrfs_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN))
 		return;
 
-	ASSERT(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
+	ASSERT(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
+	ASSERT(test_bit(EXTENT_BUFFER_CANCELLED, &eb->bflags));
 
 	memzero_extent_buffer(eb, 0, eb->len);
 	set_bit(EXTENT_BUFFER_CANCELLED, &eb->bflags);

-- 
2.41.0