Commit a83a29b3 authored by Zhihao Cheng's avatar Zhihao Cheng Committed by Wang Zhaolong
Browse files

ubifs: Remove insert_dead_orphan from replaying orphan process 

maillist inclusion
category: cleanup
bugzilla: https://gitee.com/openeuler/kernel/issues/I9MWEQ
CVE: NA

Reference: https://lore.kernel.org/lkml/20240410073751.2522830-8-chengzhihao1@huawei.com/T/



--------------------------------

UBIFS will do commit at the end of mounting process(rw mode), dead
orphans(added by insert_dead_orphan in replaying orphan) are deleted
by ubifs_orphan_end_commit(). The only reason why dead orphans are
added into orphan list is that old orpans may be lost when powercut
happens in ubifs_orphan_end_commit():
ubifs_orphan_end_commit  // TNC(updated by orphans) is not written yet
 if (c->cmt_orphans != 0)
  commit_orphans
   consolidate // traverse orphan list
  write_orph_nodes // rewrite all orphans by ubifs_leb_change
  // If dead orphans are not in list, they will be lost when powercut
  // happens, then TNC won't be updated by old orphans in next mounting.
Luckily, the condition 'c->cmt_orphans != 0' will never be true in
mounting process, there can't be new orphans added into orphan list
before mounting returned, but commit will be done at the end of mounting.

Signed-off-by: default avatarZhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: default avatarZhaoLong Wang <wangzhaolong1@huawei.com>
parent 655a0a3e

fs/ubifs/orphan.c

+0 −49
Original line number Diff line number Diff line
@@ -513,51 +513,6 @@ int ubifs_clear_orphans(struct ubifs_info *c) 
	return 0;

}



/**

 * insert_dead_orphan - insert an orphan.

 * @c: UBIFS file-system description object

 * @inum: orphan inode number

 *

 * This function is a helper to the 'do_kill_orphans()' function. The orphan

 * must be kept until the next commit, so it is added to the rb-tree and the

 * deletion list.

 */

static int insert_dead_orphan(struct ubifs_info *c, ino_t inum)

{

	struct ubifs_orphan *orphan, *o;

	struct rb_node **p, *parent = NULL;



	orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_KERNEL);

	if (!orphan)

		return -ENOMEM;

	orphan->inum = inum;



	p = &c->orph_tree.rb_node;

	while (*p) {

		parent = *p;

		o = rb_entry(parent, struct ubifs_orphan, rb);

		if (inum < o->inum)

			p = &(*p)->rb_left;

		else if (inum > o->inum)

			p = &(*p)->rb_right;

		else {

			/* Already added - no problem */

			kfree(orphan);

			return 0;

		}

	}

	c->tot_orphans += 1;

	rb_link_node(&orphan->rb, parent, p);

	rb_insert_color(&orphan->rb, &c->orph_tree);

	list_add_tail(&orphan->list, &c->orph_list);

	orphan->del = 1;

	orphan->dnext = c->orph_dnext;

	c->orph_dnext = orphan;

	dbg_mnt("ino %lu, new %d, tot %d", (unsigned long)inum,

		c->new_orphans, c->tot_orphans);

	return 0;

}



/**

 * do_kill_orphans - remove orphan inodes from the index.

 * @c: UBIFS file-system description object
@@ -655,10 +610,6 @@ static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb, 
				if (err)

					goto out_ro;

			}



			err = insert_dead_orphan(c, inum);

			if (err)

				goto out_free;

		}



		*last_cmt_no = cmt_no;