Commit d29460e5 authored by Jaegeuk Kim's avatar Jaegeuk Kim
Browse files

f2fs: avoid deadlock caused by lock order of page and lock_op 



- punch_hole
 - fill_zero
  - f2fs_lock_op
  - get_new_data_page
   - lock_page

- f2fs_write_data_pages
 - lock_page
 - do_write_data_page
  - f2fs_lock_op

Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent d1aa2453

fs/f2fs/data.c

+13 −3
Original line number Diff line number Diff line
@@ -1404,8 +1404,9 @@ int do_write_data_page(struct f2fs_io_info *fio) 
		}

	}



	if (fio->need_lock == LOCK_REQ)

		f2fs_lock_op(fio->sbi);

	/* Deadlock due to between page->lock and f2fs_lock_op */

	if (fio->need_lock == LOCK_REQ && !f2fs_trylock_op(fio->sbi))

		return -EAGAIN;



	err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);

	if (err)
@@ -1667,7 +1668,7 @@ static int f2fs_write_cache_pages(struct address_space *mapping, 
			}



			done_index = page->index;



retry_write:

			lock_page(page);



			if (unlikely(page->mapping != mapping)) {
@@ -1703,6 +1704,15 @@ static int f2fs_write_cache_pages(struct address_space *mapping, 
					unlock_page(page);

					ret = 0;

					continue;

				} else if (ret == -EAGAIN) {

					ret = 0;

					if (wbc->sync_mode == WB_SYNC_ALL) {

						cond_resched();

						congestion_wait(BLK_RW_ASYNC,

									HZ/50);

						goto retry_write;

					}

					continue;

				}

				done_index = page->index + 1;

				done = 1;