[PATCH v15 43/43] btrfs: zoned: deal with holes writing out tree-log pages
flat view
STALE2053d
From: Naohiro Aota <naohiro.aota@wdc.com>
Date: 2021-02-05 09:30:20
Also in:
linux-fsdevel
Subsystem:
btrfs file system, filesystems (vfs and infrastructure), the rest · Maintainers:
David Sterba, Alexander Viro, Christian Brauner, Linus Torvalds
Since the zoned filesystem requires sequential write out of metadata, we cannot proceed with a hole in tree-log pages. When such a hole exists, btree_write_cache_pages() will return -EAGAIN. We cannot wait for the range to be written, because it will cause a deadlock. So, let's bail out to a full commit in this case. Cc: Filipe Manana <redacted> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> --- fs/btrfs/tree-log.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) This patch solves a regression introduced by fixing patch 40. I'm sorry for the confusing patch numbering.
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 4e72794342c0..629e605cd62d 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c@@ -3120,6 +3120,14 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, */ blk_start_plug(&plug); ret = btrfs_write_marked_extents(fs_info, &log->dirty_log_pages, mark); + /* + * There is a hole writing out the extents and cannot proceed it on + * zoned filesystem, which require sequential writing. We can + * ignore the error for now, since we don't wait for completion for + * now. + */ + if (ret == -EAGAIN) + ret = 0; if (ret) { blk_finish_plug(&plug); btrfs_abort_transaction(trans, ret);
@@ -3229,7 +3237,16 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, &log_root_tree->dirty_log_pages, EXTENT_DIRTY | EXTENT_NEW); blk_finish_plug(&plug); - if (ret) { + /* + * There is a hole in the extents, and failed to sequential write + * on zoned filesystem. We cannot wait for this write outs, sinc it + * cause a deadlock. Bail out to the full commit, instead. + */ + if (ret == -EAGAIN) { + btrfs_wait_tree_log_extents(log, mark); + mutex_unlock(&log_root_tree->log_mutex); + goto out_wake_log_root; + } else if (ret) { btrfs_set_log_full_commit(trans); btrfs_abort_transaction(trans, ret); mutex_unlock(&log_root_tree->log_mutex);
--
2.30.0