[PATCH 13/16] btrfs: writepage fixup lock rearrangement

From: Goldwyn Rodrigues <rgoldwyn@suse.de>
To: linux-btrfs@vger.kernel.org
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>,
	Goldwyn Rodrigues <rgoldwyn@suse.com>
Subject: [PATCH 13/16] btrfs: writepage fixup lock rearrangement
Date: Tue, 15 Nov 2022 12:00:31 -0600	[thread overview]
Message-ID: <996e43b8178ba3e5f9db220cc9e5d437c3794f06.1668530684.git.rgoldwyn@suse.com> (raw)
In-Reply-To: <cover.1668530684.git.rgoldwyn@suse.com>

Perform extent lock before pages while performing
writepage_fixup_worker.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
---
 fs/btrfs/inode.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index b421260d52e2..2806ef69122e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2909,6 +2909,7 @@ static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
 	u64 page_end;
 	int ret = 0;
 	bool free_delalloc_space = true;
+	bool flushed = false;
 
 	fixup = container_of(work, struct btrfs_writepage_fixup, work);
 	page = fixup->page;
@@ -2920,9 +2921,16 @@ static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
 	 * This is similar to page_mkwrite, we need to reserve the space before
 	 * we take the page lock.
 	 */
+reserve:
 	ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start,
 					   PAGE_SIZE);
+	if (ret == -EDQUOT && !flushed) {
+		btrfs_qgroup_flush(inode->root);
+		flushed = true;
+		goto reserve;
+	}
 again:
+	lock_extent(&inode->io_tree, page_start, page_end, NULL);
 	lock_page(page);
 
 	/*
@@ -2965,19 +2973,18 @@ static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
 	if (ret)
 		goto out_page;
 
-	lock_extent(&inode->io_tree, page_start, page_end, &cached_state);
-
 	/* already ordered? We're done */
 	if (PageOrdered(page))
 		goto out_reserved;
 
 	ordered = btrfs_lookup_ordered_range(inode, page_start, PAGE_SIZE);
 	if (ordered) {
-		unlock_extent(&inode->io_tree, page_start, page_end,
-			      &cached_state);
 		unlock_page(page);
+		unlock_extent(&inode->io_tree, page_start, page_end,
+			      NULL);
 		btrfs_start_ordered_extent(ordered, 1);
 		btrfs_put_ordered_extent(ordered);
+
 		goto again;
 	}
 
@@ -3000,7 +3007,6 @@ static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
 	if (free_delalloc_space)
 		btrfs_delalloc_release_space(inode, data_reserved, page_start,
 					     PAGE_SIZE, true);
-	unlock_extent(&inode->io_tree, page_start, page_end, &cached_state);
 out_page:
 	if (ret) {
 		/*
-- 
2.35.3

