Btrfs: fix oops after block group lookup

Signed-off-by: Chris Mason <chris.mason@oracle.com>

4 files changed, 21 insertions, 20 deletions

diff --git a/fs/btrfs/TODO b/fs/btrfs/TODO
index 61d25b5de287..d9b6d38c603a 100644
--- a/fs/btrfs/TODO
+++ b/fs/btrfs/TODO
@@ -16,6 +16,5 @@
 * Use relocation to try and fix write errors
 * Make allocator much smarter
 * xattrs (directory streams for regular files)
-* fsck
 * Scrub & defrag
 
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 5ab25a0cb16a..4e136b7b03ae 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -998,6 +998,9 @@ static inline void btrfs_mark_buffer_dirty(struct buffer_head *bh)
         btrfs_item_offset((leaf)->items + (slot))))
 
 /* extent-tree.c */
+struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
+                                                         btrfs_fs_info *info,
+                                                         u64 blocknr);
 struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
                                                  struct btrfs_block_group_cache
                                                  *hint, u64 search_start,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 645a4228bfe2..f509ffa38d03 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -135,9 +135,9 @@ printk("cache block group %Lu\n", block_group->key.objectid);
         return 0;
 }
 
-static struct btrfs_block_group_cache *lookup_block_group(struct
-                                                          btrfs_fs_info *info,
-                                                          u64 blocknr)
+struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
+                                                         btrfs_fs_info *info,
+                                                         u64 blocknr)
 {
         struct btrfs_block_group_cache *block_group;
         int ret;
@@ -208,7 +208,8 @@ out:
         return max(cache->last_alloc, search_start);
 
 new_group:
-        cache = lookup_block_group(root->fs_info, last + cache->key.offset - 1);
+        cache = btrfs_lookup_block_group(root->fs_info,
+                                         last + cache->key.offset - 1);
         if (!cache) {
                 return max((*cache_ret)->last_alloc, search_start);
         }
@@ -250,7 +251,7 @@ struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
 
         if (search_start) {
                 struct btrfs_block_group_cache *shint;
-                shint = lookup_block_group(info, search_start);
+                shint = btrfs_lookup_block_group(info, search_start);
                 if (shint->data == data) {
                         used = btrfs_block_group_used(&shint->item);
                         if (used + shint->pinned <
@@ -576,7 +577,7 @@ static int update_block_group(struct btrfs_trans_handle *trans,
         int ret;
 
         while(total) {
-                cache = lookup_block_group(info, blocknr);
+                cache = btrfs_lookup_block_group(info, blocknr);
                 if (!cache) {
                         printk(KERN_CRIT "blocknr %Lu lookup failed\n",
                                blocknr);
@@ -677,8 +678,8 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct
                         first = gang[0];
                 for (i = 0; i < ret; i++) {
                         clear_radix_bit(pinned_radix, gang[i]);
-                        block_group = lookup_block_group(root->fs_info,
-                                                         gang[i]);
+                        block_group = btrfs_lookup_block_group(root->fs_info,
+                                                               gang[i]);
                         if (block_group) {
                                 WARN_ON(block_group->pinned == 0);
                                 block_group->pinned--;
@@ -751,7 +752,8 @@ static int pin_down_block(struct btrfs_root *root, u64 blocknr, int pending)
                 err = set_radix_bit(&root->fs_info->pinned_radix, blocknr);
                 if (!err) {
                         struct btrfs_block_group_cache *cache;
-                        cache = lookup_block_group(root->fs_info, blocknr);
+                        cache = btrfs_lookup_block_group(root->fs_info,
+                                                         blocknr);
                         if (cache)
                                 cache->pinned++;
                 }
@@ -851,7 +853,8 @@ static int del_pending_extents(struct btrfs_trans_handle *trans, struct
                 for (i = 0; i < ret; i++) {
                         wret = set_radix_bit(pinned_radix, gang[i]);
                         if (wret == 0) {
-                                cache = lookup_block_group(extent_root->fs_info,
+                                cache =
+                                  btrfs_lookup_block_group(extent_root->fs_info,
                                                            gang[i]);
                                 if (cache)
                                         cache->pinned++;
@@ -938,7 +941,7 @@ static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
         if (search_end == (u64)-1)
                 search_end = btrfs_super_total_blocks(info->disk_super);
         if (hint_block) {
-                block_group = lookup_block_group(info, hint_block);
+                block_group = btrfs_lookup_block_group(info, hint_block);
                 block_group = btrfs_find_block_group(root, block_group,
                                                      hint_block, data, 1);
         } else {
@@ -1118,7 +1121,7 @@ check_pending:
                 info->extent_tree_prealloc_nr = total_found;
         }
         if (!data) {
-                block_group = lookup_block_group(info, ins->objectid);
+                block_group = btrfs_lookup_block_group(info, ins->objectid);
                 if (block_group) {
                         if (fill_prealloc)
                                 block_group->last_prealloc =
@@ -1143,7 +1146,7 @@ new_group:
                 else
                         wrapped = 1;
         }
-        block_group = lookup_block_group(info, search_start);
+        block_group = btrfs_lookup_block_group(info, search_start);
         cond_resched();
         if (!full_scan)
                 block_group = btrfs_find_block_group(root, block_group,
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 2b24a5a2be63..9749090cfbb8 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -62,7 +62,6 @@ static void btrfs_read_locked_inode(struct inode *inode)
         struct btrfs_inode_item *inode_item;
         struct btrfs_root *root = BTRFS_I(inode)->root;
         struct btrfs_key location;
-        struct btrfs_block_group_cache *alloc_group;
         u64 alloc_group_block;
         int ret;
 
@@ -95,11 +94,8 @@ static void btrfs_read_locked_inode(struct inode *inode)
         inode->i_blocks = btrfs_inode_nblocks(inode_item);
         inode->i_generation = btrfs_inode_generation(inode_item);
         alloc_group_block = btrfs_inode_block_group(inode_item);
-        ret = radix_tree_gang_lookup(&root->fs_info->block_group_radix,
-                                     (void **)&alloc_group,
-                                     alloc_group_block, 1);
-        BUG_ON(!ret);
-        BTRFS_I(inode)->block_group = alloc_group;
+        BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
+                                                       alloc_group_block);
 
         btrfs_free_path(path);
         inode_item = NULL;