btrfs: Panic on bad rbtree operations
Jeff Mahoney [Tue, 4 Oct 2011 03:22:33 +0000 (23:22 -0400)]
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>

fs/btrfs/ordered-data.c
fs/btrfs/relocation.c

index a1c9404..2857f28 100644 (file)
@@ -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;
 }
 
index 8c1aae2..e5996ff 100644 (file)
@@ -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;