btrfs: Panic on bad rbtree operations

The ordered data and relocation trees have BUG_ONs to protect against
bad tree operations.

This patch replaces them with a panic that will report the problem.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>

2 files changed, 39 insertions, 9 deletions

diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index a1c940425307..2857f28e20e2 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -59,6 +59,14 @@ static struct rb_node *tree_insert(struct rb_root *root, u64 file_offset,
         return NULL;
 }
 
+static void ordered_data_tree_panic(struct inode *inode, int errno,
+                                               u64 offset)
+{
+        struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+        btrfs_panic(fs_info, errno, "Inconsistency in ordered tree at offset "
+                    "%llu\n", (unsigned long long)offset);
+}
+
 /*
  * look for a given offset in the tree, and if it can't be found return the
  * first lesser offset
@@ -207,7 +215,8 @@ static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
         spin_lock(&tree->lock);
         node = tree_insert(&tree->tree, file_offset,
                            &entry->rb_node);
-        BUG_ON(node);
+        if (node)
+                ordered_data_tree_panic(inode, -EEXIST, file_offset);
         spin_unlock(&tree->lock);
 
         spin_lock(&BTRFS_I(inode)->root->fs_info->ordered_extent_lock);
@@ -215,7 +224,6 @@ static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
                       &BTRFS_I(inode)->root->fs_info->ordered_extents);
         spin_unlock(&BTRFS_I(inode)->root->fs_info->ordered_extent_lock);
 
-        BUG_ON(node);
         return 0;
 }
 
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 8c1aae2c845d..e5996ff8aaa4 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -326,6 +326,19 @@ static struct rb_node *tree_search(struct rb_root *root, u64 bytenr)
         return NULL;
 }
 
+void backref_tree_panic(struct rb_node *rb_node, int errno,
+                                          u64 bytenr)
+{
+
+        struct btrfs_fs_info *fs_info = NULL;
+        struct backref_node *bnode = rb_entry(rb_node, struct backref_node,
+                                              rb_node);
+        if (bnode->root)
+                fs_info = bnode->root->fs_info;
+        btrfs_panic(fs_info, errno, "Inconsistency in backref cache "
+                    "found at offset %llu\n", (unsigned long long)bytenr);
+}
+
 /*
  * walk up backref nodes until reach node presents tree root
  */
@@ -452,7 +465,8 @@ static void update_backref_node(struct backref_cache *cache,
         rb_erase(&node->rb_node, &cache->rb_root);
         node->bytenr = bytenr;
         rb_node = tree_insert(&cache->rb_root, node->bytenr, &node->rb_node);
-        BUG_ON(rb_node);
+        if (rb_node)
+                backref_tree_panic(rb_node, -EEXIST, bytenr);
 }
 
 /*
@@ -999,7 +1013,8 @@ next:
         if (!cowonly) {
                 rb_node = tree_insert(&cache->rb_root, node->bytenr,
                                       &node->rb_node);
-                BUG_ON(rb_node);
+                if (rb_node)
+                        backref_tree_panic(rb_node, -EEXIST, node->bytenr);
                 list_add_tail(&node->lower, &cache->leaves);
         }
 
@@ -1034,7 +1049,9 @@ next:
                 if (!cowonly) {
                         rb_node = tree_insert(&cache->rb_root, upper->bytenr,
                                               &upper->rb_node);
-                        BUG_ON(rb_node);
+                        if (rb_node)
+                                backref_tree_panic(rb_node, -EEXIST,
+                                                   upper->bytenr);
                 }
 
                 list_add_tail(&edge->list[UPPER], &upper->lower);
@@ -1180,7 +1197,8 @@ static int clone_backref_node(struct btrfs_trans_handle *trans,
 
         rb_node = tree_insert(&cache->rb_root, new_node->bytenr,
                               &new_node->rb_node);
-        BUG_ON(rb_node);
+        if (rb_node)
+                backref_tree_panic(rb_node, -EEXIST, new_node->bytenr);
 
         if (!new_node->lowest) {
                 list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) {
@@ -1252,7 +1270,8 @@ static int __update_reloc_root(struct btrfs_root *root, int del)
                 rb_node = tree_insert(&rc->reloc_root_tree.rb_root,
                                       node->bytenr, &node->rb_node);
                 spin_unlock(&rc->reloc_root_tree.lock);
-                BUG_ON(rb_node);
+                if (rb_node)
+                        backref_tree_panic(rb_node, -EEXIST, node->bytenr);
         } else {
                 list_del_init(&root->root_list);
                 kfree(node);
@@ -3154,7 +3173,8 @@ static int add_tree_block(struct reloc_control *rc,
         block->key_ready = 0;
 
         rb_node = tree_insert(blocks, block->bytenr, &block->rb_node);
-        BUG_ON(rb_node);
+        if (rb_node)
+                backref_tree_panic(rb_node, -EEXIST, block->bytenr);
 
         return 0;
 }
@@ -3426,7 +3446,9 @@ static int find_data_references(struct reloc_control *rc,
                         block->key_ready = 1;
                         rb_node = tree_insert(blocks, block->bytenr,
                                               &block->rb_node);
-                        BUG_ON(rb_node);
+                        if (rb_node)
+                                backref_tree_panic(rb_node, -EEXIST,
+                                                   block->bytenr);
                 }
                 if (counted)
                         added = 1;