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: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Jaegeuk Kim 2017-06-21 17:52:39 -07:00
parent d1aa245354
commit d29460e5cf
1 changed files with 13 additions and 3 deletions

View File

@ -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 @@ retry:
}
done_index = page->index;
retry_write:
lock_page(page);
if (unlikely(page->mapping != mapping)) {
@ -1703,6 +1704,15 @@ continue_unlock:
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;