f2fs: do not preallocate blocks which has wrong buffer
Sheng Yong reports needless preallocation if write(small_buffer, large_size)
is called.
In that case, f2fs preallocates large_size, but vfs returns early due to
small_buffer size. Let's detect it before preallocation phase in f2fs.
Reported-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 848d110..2ea8021 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -749,6 +749,9 @@
struct f2fs_map_blocks map;
int err = 0;
+ if (is_inode_flag_set(inode, FI_NO_PREALLOC))
+ return 0;
+
map.m_lblk = F2FS_BLK_ALIGN(iocb->ki_pos);
map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from));
if (map.m_len > map.m_lblk)
@@ -1653,7 +1656,8 @@
* we already allocated all the blocks, so we don't need to get
* the block addresses when there is no need to fill the page.
*/
- if (!f2fs_has_inline_data(inode) && len == PAGE_SIZE)
+ if (!f2fs_has_inline_data(inode) && len == PAGE_SIZE &&
+ !is_inode_flag_set(inode, FI_NO_PREALLOC))
return 0;
if (f2fs_has_inline_data(inode) ||