Commit 03e860bd authored by From: Nick Piggin's avatar From: Nick Piggin Committed by Jens Axboe
Browse files

btrfs: fix inode rbtree corruption 



Node may not be inserted over existing node. This causes inode tree
corruption and I was seeing crashes in inode_tree_del which I can not
reproduce after this patch.

The other way to fix this would be to tie inode lifetime in the rbtree
with inode while not in freeing state. I had a look at this but it is
not so trivial at this point. At least this patch gets things working again.

Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
Cc: Chris Mason <chris.mason@oracle.com>
Acked-by: default avatarYan Zheng <zheng.yan@oracle.com>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent df4ecf15

fs/btrfs/inode.c

+14 −7
Original line number Diff line number Diff line
@@ -3099,8 +3099,12 @@ static void inode_tree_add(struct inode *inode) 
{

	struct btrfs_root *root = BTRFS_I(inode)->root;

	struct btrfs_inode *entry;

	struct rb_node **p = &root->inode_tree.rb_node;

	struct rb_node *parent = NULL;

	struct rb_node **p;

	struct rb_node *parent;



again:

	p = &root->inode_tree.rb_node;

	parent = NULL;



	spin_lock(&root->inode_lock);

	while (*p) {
@@ -3108,13 +3112,16 @@ static void inode_tree_add(struct inode *inode) 
		entry = rb_entry(parent, struct btrfs_inode, rb_node);



		if (inode->i_ino < entry->vfs_inode.i_ino)

			p = &(*p)->rb_left;

			p = &parent->rb_left;

		else if (inode->i_ino > entry->vfs_inode.i_ino)

			p = &(*p)->rb_right;

			p = &parent->rb_right;

		else {

			WARN_ON(!(entry->vfs_inode.i_state &

				  (I_WILL_FREE | I_FREEING | I_CLEAR)));

			break;

			rb_erase(parent, &root->inode_tree);

			RB_CLEAR_NODE(parent);

			spin_unlock(&root->inode_lock);

			goto again;

		}

	}

	rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
@@ -3126,12 +3133,12 @@ static void inode_tree_del(struct inode *inode) 
{

	struct btrfs_root *root = BTRFS_I(inode)->root;



	if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {

	spin_lock(&root->inode_lock);

	if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {

		rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);

		spin_unlock(&root->inode_lock);

		RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);

	}

	spin_unlock(&root->inode_lock);

}



static noinline void init_btrfs_i(struct inode *inode)

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