dm btree: fix serious bug in btree_split_beneath()

[pandora-kernel.git] / drivers / md / persistent-data / dm-btree.c

diff --git a/drivers/md/persistent-data/dm-btree.c b/drivers/md/persistent-data/dm-btree.c
index bbb2ec5..008231f 100644 (file)
--- a/drivers/md/persistent-data/dm-btree.c
+++ b/drivers/md/persistent-data/dm-btree.c
@@ -231,12 +231,22 @@ static void pop_frame(struct del_stack *s)
        dm_tm_unlock(s->tm, f->b);
 }
 
+static void unlock_all_frames(struct del_stack *s)
+{
+       struct frame *f;
+
+       while (unprocessed_frames(s)) {
+               f = s->spine + s->top--;
+               dm_tm_unlock(s->tm, f->b);
+       }
+}
+
 int dm_btree_del(struct dm_btree_info *info, dm_block_t root)
 {
        int r;
        struct del_stack *s;
 
-       s = kmalloc(sizeof(*s), GFP_KERNEL);
+       s = kmalloc(sizeof(*s), GFP_NOIO);
        if (!s)
                return -ENOMEM;
        s->tm = info->tm;
@@ -286,9 +296,13 @@ int dm_btree_del(struct dm_btree_info *info, dm_block_t root)
                        f->current_child = f->nr_children;
                }
        }
-
 out:
+       if (r) {
+               /* cleanup all frames of del_stack */
+               unlock_all_frames(s);
+       }
        kfree(s);
+
        return r;
 }
 EXPORT_SYMBOL_GPL(dm_btree_del);
@@ -451,8 +465,10 @@ static int btree_split_sibling(struct shadow_spine *s, dm_block_t root,
 
        r = insert_at(sizeof(__le64), pn, parent_index + 1,
                      le64_to_cpu(rn->keys[0]), &location);
-       if (r)
+       if (r) {
+               unlock_block(s->info, right);
                return r;
+       }
 
        if (key < le64_to_cpu(rn->keys[0])) {
                unlock_block(s->info, right);
@@ -503,7 +519,7 @@ static int btree_split_beneath(struct shadow_spine *s, uint64_t key)
 
        r = new_block(s->info, &right);
        if (r < 0) {
-               /* FIXME: put left */
+               unlock_block(s->info, left);
                return r;
        }
 
@@ -552,23 +568,8 @@ static int btree_split_beneath(struct shadow_spine *s, uint64_t key)
        pn->keys[1] = rn->keys[0];
        memcpy_disk(value_ptr(pn, 1, sizeof(__le64)), &val, sizeof(__le64));
 
-       /*
-        * rejig the spine.  This is ugly, since it knows too
-        * much about the spine
-        */
-       if (s->nodes[0] != new_parent) {
-               unlock_block(s->info, s->nodes[0]);
-               s->nodes[0] = new_parent;
-       }
-       if (key < le64_to_cpu(rn->keys[0])) {
-               unlock_block(s->info, right);
-               s->nodes[1] = left;
-       } else {
-               unlock_block(s->info, left);
-               s->nodes[1] = right;
-       }
-       s->count = 2;
-
+       unlock_block(s->info, left);
+       unlock_block(s->info, right);
        return 0;
 }
 
@@ -647,12 +648,7 @@ static int insert(struct dm_btree_info *info, dm_block_t root,
        struct btree_node *n;
        struct dm_btree_value_type le64_type;
 
-       le64_type.context = NULL;
-       le64_type.size = sizeof(__le64);
-       le64_type.inc = NULL;
-       le64_type.dec = NULL;
-       le64_type.equal = NULL;
-
+       init_le64_type(info->tm, &le64_type);
        init_shadow_spine(&spine, info);
 
        for (level = 0; level < (info->levels - 1); level++) {