f2fs: truncate preallocated blocks in error case

commit dc7a10ddee0c56c6d891dd18de5c4ee9869545e0 upstream.

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>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 29c5f799890ca91d91d16e2a4e33af04a65bc17e..72c6a9e9a9b45b041386f78878ed6003302b8e35 100644 (file)
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2694,11 +2694,16 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
        inode_lock(inode);
        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)))
                        set_inode_flag(inode, FI_NO_PREALLOC);
 
+               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);
@@ -2710,6 +2715,10 @@ 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);
        }