btrfs: zoned: don't clear dirty flag of extent buffer

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

On writeout, when encountering a marked extent_buffer, zero it out.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Johannes Thumshirn 2023-11-23 07:47:16 -08:00 committed by David Sterba
parent cbf44cd93d
commit aa6313e6ff
3 changed files with 22 additions and 4 deletions

View File

@ -254,8 +254,13 @@ blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio)
if (WARN_ON_ONCE(bbio->bio.bi_iter.bi_size != eb->len))
return BLK_STS_IOERR;
/*
* If an extent_buffer is marked as EXTENT_BUFFER_ZONED_ZEROOUT, don't
* checksum it but zero-out its content. This is done to preserve
* ordering of I/O without unnecessarily writing out data.
*/
if (test_bit(EXTENT_BUFFER_ZONED_ZEROOUT, &eb->bflags)) {
WARN_ON_ONCE(found_start != 0);
memzero_extent_buffer(eb, 0, eb->len);
return BLK_STS_OK;
}

View File

@ -3761,6 +3761,20 @@ void btrfs_clear_buffer_dirty(struct btrfs_trans_handle *trans,
if (trans && btrfs_header_generation(eb) != trans->transid)
return;
/*
* Instead of clearing the dirty flag off of the buffer, mark it as
* EXTENT_BUFFER_ZONED_ZEROOUT. This allows us to preserve
* write-ordering in zoned mode, without the need to later re-dirty
* the extent_buffer.
*
* The actual zeroout of the buffer will happen later in
* btree_csum_one_bio.
*/
if (btrfs_is_zoned(fs_info)) {
set_bit(EXTENT_BUFFER_ZONED_ZEROOUT, &eb->bflags);
return;
}
if (!test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags))
return;
@ -4152,8 +4166,6 @@ 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_ZONED_ZEROOUT, &eb->bflags));
if (check_eb_range(eb, start, len))
return;

View File

@ -1713,7 +1713,8 @@ 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_ZONED_ZEROOUT, &eb->bflags));
memzero_extent_buffer(eb, 0, eb->len);
set_bit(EXTENT_BUFFER_ZONED_ZEROOUT, &eb->bflags);