[PATCH] f2fs: fix FG GC failure when file in victim is pinned

[Jiucheng Xu via B4 Relay]

From: Jiucheng Xu <jiucheng.xu@xxxxxxxxxxx>

When continuous write operations occur in the system, BG GC fails to
work. This leads to large dirty_segments and small free_segments. If
fallocate() is performed on a pinned file with the allocated space
exceeding the free_segment, FG_GC reclamation fails.

The reason is that the file corresponding to the block in the victim is
pinned, causing gc_data_segment() to fail. Since the condition sec_freed
< gc_control->nr_free_secs isn't satisfied, GC stops, resulting in the
failure of f2fs_fallocate() allocation.

Setting gc_control->nr_free_secs = 1 make FG GC continue searching
for new victim.

Signed-off-by: Jiucheng Xu <jiucheng.xu@xxxxxxxxxxx>
---
 fs/f2fs/file.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 8acdd94272a0ced448e0ba21635d702cfec10682..3e49a73bbf3a184a314e97bff9509a66c27eac00 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -1883,7 +1883,7 @@ static int f2fs_expand_inode_data(struct inode *inode, loff_t offset,
 			.init_gc_type = FG_GC,
 			.should_migrate_blocks = false,
 			.err_gc_skipped = true,
-			.nr_free_secs = 0 };
+			.nr_free_secs = 1 };
 	pgoff_t pg_start, pg_end;
 	loff_t new_size;
 	loff_t off_end;

---
base-commit: b51f606aa323d553d786ed681a213f134dc688d6
change-id: 20260620-origin-dev-99cdccc83800

Best regards,
-- 
Jiucheng Xu <jiucheng.xu@xxxxxxxxxxx>