f2fs: truncate preallocated blocks in error case

If write is failed, we must deallocate the blocks that we couldn't write.

Cc: stable@vger.kernel.org
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 8068b015ece59b577333e25ec8ee5f6d871f0983..6b94f19b3fa8d40a9e7da5151e19064ccca50d7d 100644 (file)
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2911,6 +2911,8 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 
        ret = generic_write_checks(iocb, from);
        if (ret > 0) {
+               bool preallocated = false;
+               size_t target_size = 0;
                int err;
 
                if (iov_iter_fault_in_readable(from, iov_iter_count(from)))
@@ -2927,6 +2929,9 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                                }
 
                } else {
+                       preallocated = true;
+                       target_size = iocb->ki_pos + iov_iter_count(from);
+
                        err = f2fs_preallocate_blocks(iocb, from);
                        if (err) {
                                clear_inode_flag(inode, FI_NO_PREALLOC);
@@ -2939,6 +2944,10 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                blk_finish_plug(&plug);
                clear_inode_flag(inode, FI_NO_PREALLOC);
 
+               /* if we couldn't write data, we should deallocate blocks. */
+               if (preallocated && i_size_read(inode) < target_size)
+                       f2fs_truncate(inode);
+
                if (ret > 0)
                        f2fs_update_iostat(F2FS_I_SB(inode), APP_WRITE_IO, ret);
        }