[PATCH V3 5/5] ext4: make fallocate retry when err is ENOSPC

From: Wang Jianchao <jianchao.wan9@gmail.com>
To: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: tytso@mit.edu, adilger.kernel@dilger.ca
Subject: [PATCH V3 5/5] ext4: make fallocate retry when err is ENOSPC
Date: Sat, 24 Jul 2021 15:41:24 +0800	[thread overview]
Message-ID: <20210724074124.25731-6-jianchao.wan9@gmail.com> (raw)
In-Reply-To: <20210724074124.25731-1-jianchao.wan9@gmail.com>

From: Wang Jianchao <wangjianchao@kuaishou.com>

The blocks may be waiting for journal commit to be freed back to
mb buddy. Let fallocate wait and retry in that case.

Signed-off-by: Wang Jianchao <wangjianchao@kuaishou.com>
---
 fs/ext4/extents.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 92ad64b89d9b..ad0b874d3448 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4635,7 +4635,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 	struct inode *inode = file_inode(file);
 	loff_t new_size = 0;
 	unsigned int max_blocks;
-	int ret = 0;
+	int ret = 0, retries = 0;
 	int flags;
 	ext4_lblk_t lblk;
 	unsigned int blkbits = inode->i_blkbits;
@@ -4656,6 +4656,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 		     FALLOC_FL_INSERT_RANGE))
 		return -EOPNOTSUPP;
 
+retry:
 	ext4_fc_start_update(inode);
 
 	if (mode & FALLOC_FL_PUNCH_HOLE) {
@@ -4722,6 +4723,9 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 	trace_ext4_fallocate_exit(inode, offset, max_blocks, ret);
 exit:
 	ext4_fc_stop_update(inode);
+	if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+		goto retry;
+
 	return ret;
 }
 
-- 
2.17.1

