[PATCH 6/6] ext4: skip ext4_update_disksize_before_punch() in WRITE_ZEROES

[yizhang089@gmail.com]

From: Zhang Yi <yi.zhang@huawei.com>

FALLOC_FL_WRITE_ZEROES is mutually exclusive with FALLOC_FL_KEEP_SIZE.
In ext4_zero_range(), when end > i_disksize, new_size is always set to
end for WRITE_ZEROES, so the i_disksize update should not be lost.

The ext4_update_disksize_before_punch() call is only needed for the
ZERO_RANGE path in ext4_zero_range(), as it handles the case where
KEEP_SIZE may preserve the original disk size. Skip it for WRITE_ZEROES
to avoid unnecessary work and potential confusion.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
---
 fs/ext4/extents.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index c083703bf704..38753c2ef910 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4748,9 +4748,11 @@ static long ext4_zero_range(struct file *file, loff_t offset,
 			return ret;
 	}
 
-	ret = ext4_update_disksize_before_punch(inode, offset, len);
-	if (ret)
-		return ret;
+	if (mode & FALLOC_FL_ZERO_RANGE) {
+		ret = ext4_update_disksize_before_punch(inode, offset, len);
+		if (ret)
+			return ret;
+	}
 
 	/* Now release the pages and zero block aligned part of pages */
 	ret = ext4_truncate_page_cache_block_range(inode, offset, end);
-- 
2.53.0