From: Theodore Ts'o Date: Fri, 13 Aug 2021 15:20:48 +0000 (-0400) Subject: ext4: if zeroout fails fall back to splitting the extent node X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=308c57ccf4318236be75dfa251c84713e694457b;p=linux.git ext4: if zeroout fails fall back to splitting the extent node If the underlying storage device is using thin-provisioning, it's possible for a zeroout operation to return ENOSPC. Commit df22291ff0fd ("ext4: Retry block allocation if we have free blocks left") added logic to retry block allocation since we might get free block after we commit a transaction. But the ENOSPC from thin-provisioning will confuse ext4, and lead to an infinite loop. Since using zeroout instead of splitting the extent node is an optimization, if it fails, we might as well fall back to splitting the extent node. Reported-by: yangerkun Signed-off-by: Theodore Ts'o --- diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 92ad64b89d9b5..501516cadc1b3 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3569,7 +3569,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, split_map.m_len - ee_block); err = ext4_ext_zeroout(inode, &zero_ex1); if (err) - goto out; + goto fallback; split_map.m_len = allocated; } if (split_map.m_lblk - ee_block + split_map.m_len < @@ -3583,7 +3583,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, ext4_ext_pblock(ex)); err = ext4_ext_zeroout(inode, &zero_ex2); if (err) - goto out; + goto fallback; } split_map.m_len += split_map.m_lblk - ee_block; @@ -3592,6 +3592,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle, } } +fallback: err = ext4_split_extent(handle, inode, ppath, &split_map, split_flag, flags); if (err > 0)