Unverified Commit 9b2f1457 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!12071 btrfs: clean up our handling of refs == 0 in snapshot delete 

Merge Pull Request from: @ci-robot 
 
PR sync from: Baokun Li <libaokun1@huawei.com>
https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/message/ZX3UI6CHK4CXWCA2O4MEAIQQSRALWGRV/ 
 
https://gitee.com/src-openeuler/kernel/issues/IAU9NE 
 
Link:https://gitee.com/openeuler/kernel/pulls/12071

 

Reviewed-by: default avatarzhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: default avatarZhang Changzhong <zhangchangzhong@huawei.com>
parents bd281fec 279c18a6

fs/btrfs/extent-tree.c

+23 −5
Original line number Diff line number Diff line
@@ -8400,7 +8400,15 @@ static noinline void reada_walk_down(struct btrfs_trans_handle *trans, 
		/* We don't care about errors in readahead. */

		if (ret < 0)

			continue;

		BUG_ON(refs == 0);



		/*

		 * This could be racey, it's conceivable that we raced and end

		 * up with a bogus refs count, if that's the case just skip, if

		 * we are actually corrupt we will notice when we look up

		 * everything again with our locks.

		 */

		if (refs == 0)

			continue;



		if (wc->stage == DROP_REFERENCE) {

			if (refs == 1)
@@ -8467,7 +8475,11 @@ static noinline int walk_down_proc(struct btrfs_trans_handle *trans, 
		BUG_ON(ret == -ENOMEM);

		if (ret)

			return ret;

		BUG_ON(wc->refs[level] == 0);

		if (unlikely(wc->refs[level] == 0)) {

			btrfs_err(fs_info, "bytenr %llu has 0 references, expect > 0",

				  eb->start);

			return -EUCLEAN;

		}

	}



	if (wc->stage == DROP_REFERENCE) {
@@ -8575,8 +8587,9 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans, 
		goto out_unlock;



	if (unlikely(wc->refs[level - 1] == 0)) {

		btrfs_err(fs_info, "Missing references.");

		ret = -EIO;

		btrfs_err(fs_info, "bytenr %llu has 0 references, expect > 0",

			  bytenr);

		ret = -EUCLEAN;

		goto out_unlock;

	}

	*lookup_info = 0;
@@ -8744,7 +8757,12 @@ static noinline int walk_up_proc(struct btrfs_trans_handle *trans, 
				path->locks[level] = 0;

				return ret;

			}

			BUG_ON(wc->refs[level] == 0);

			if (unlikely(wc->refs[level] == 0)) {

				btrfs_tree_unlock_rw(eb, path->locks[level]);

				btrfs_err(fs_info, "bytenr %llu has 0 references, expect > 0",

					  eb->start);

				return -EUCLEAN;

			}

			if (wc->refs[level] == 1) {

				btrfs_tree_unlock_rw(eb, path->locks[level]);

				path->locks[level] = 0;