From 03e860bd9f6a3cca747b0795bed26279a8b420a0 Mon Sep 17 00:00:00 2001 From: "From: Nick Piggin" Date: Fri, 21 Aug 2009 10:09:44 +0200 Subject: [PATCH] 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: Nick Piggin Cc: Chris Mason Acked-by: Yan Zheng Signed-off-by: Jens Axboe --- fs/btrfs/inode.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 272b9b2bea86..59cba180fe83 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -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; + spin_lock(&root->inode_lock); if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) { - spin_lock(&root->inode_lock); 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) -- 2.30.2