dm thin metadata: fix bug in dm_thin_remove_range()

[firefly-linux-kernel-4.4.55.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 0918a7c5f809766ea43faa0c5db96f1b22221325..7e5b7f12958a073f7f5ecfd86df60f6ba20f3d95 100644 (file)
--- a/drivers/md/persistent-data/dm-btree.c
+++ b/drivers/md/persistent-data/dm-btree.c
@@ -63,6 +63,11 @@ int lower_bound(struct btree_node *n, uint64_t key)
        return bsearch(n, key, 0);
 }
 
+static int upper_bound(struct btree_node *n, uint64_t key)
+{
+       return bsearch(n, key, 1);
+}
+
 void inc_children(struct dm_transaction_manager *tm, struct btree_node *n,
                  struct dm_btree_value_type *vt)
 {
@@ -392,6 +397,82 @@ int dm_btree_lookup(struct dm_btree_info *info, dm_block_t root,
 }
 EXPORT_SYMBOL_GPL(dm_btree_lookup);
 
+static int dm_btree_lookup_next_single(struct dm_btree_info *info, dm_block_t root,
+                                      uint64_t key, uint64_t *rkey, void *value_le)
+{
+       int r, i;
+       uint32_t flags, nr_entries;
+       struct dm_block *node;
+       struct btree_node *n;
+
+       r = bn_read_lock(info, root, &node);
+       if (r)
+               return r;
+
+       n = dm_block_data(node);
+       flags = le32_to_cpu(n->header.flags);
+       nr_entries = le32_to_cpu(n->header.nr_entries);
+
+       if (flags & INTERNAL_NODE) {
+               i = lower_bound(n, key);
+               if (i < 0 || i >= nr_entries) {
+                       r = -ENODATA;
+                       goto out;
+               }
+
+               r = dm_btree_lookup_next_single(info, value64(n, i), key, rkey, value_le);
+               if (r == -ENODATA && i < (nr_entries - 1)) {
+                       i++;
+                       r = dm_btree_lookup_next_single(info, value64(n, i), key, rkey, value_le);
+               }
+
+       } else {
+               i = upper_bound(n, key);
+               if (i < 0 || i >= nr_entries) {
+                       r = -ENODATA;
+                       goto out;
+               }
+
+               *rkey = le64_to_cpu(n->keys[i]);
+               memcpy(value_le, value_ptr(n, i), info->value_type.size);
+       }
+out:
+       dm_tm_unlock(info->tm, node);
+       return r;
+}
+
+int dm_btree_lookup_next(struct dm_btree_info *info, dm_block_t root,
+                        uint64_t *keys, uint64_t *rkey, void *value_le)
+{
+       unsigned level;
+       int r = -ENODATA;
+       __le64 internal_value_le;
+       struct ro_spine spine;
+
+       init_ro_spine(&spine, info);
+       for (level = 0; level < info->levels - 1u; level++) {
+               r = btree_lookup_raw(&spine, root, keys[level],
+                                    lower_bound, rkey,
+                                    &internal_value_le, sizeof(uint64_t));
+               if (r)
+                       goto out;
+
+               if (*rkey != keys[level]) {
+                       r = -ENODATA;
+                       goto out;
+               }
+
+               root = le64_to_cpu(internal_value_le);
+       }
+
+       r = dm_btree_lookup_next_single(info, root, keys[level], rkey, value_le);
+out:
+       exit_ro_spine(&spine);
+       return r;
+}
+
+EXPORT_SYMBOL_GPL(dm_btree_lookup_next);
+
 /*
  * Splits a node by creating a sibling node and shifting half the nodes
  * contents across.  Assumes there is a parent node, and it has room for