mutex_unlock(&fs_info->qgroup_ioctl_lock);
return ret;
}
+
+static int comp_oper_exist(struct btrfs_qgroup_operation *oper1,
+ struct btrfs_qgroup_operation *oper2)
+{
+ /*
+ * Ignore seq and type here, we're looking for any operation
+ * at all related to this extent on that root.
+ */
+ if (oper1->bytenr < oper2->bytenr)
+ return -1;
+ if (oper1->bytenr > oper2->bytenr)
+ return 1;
+ if (oper1->ref_root < oper2->ref_root)
+ return -1;
+ if (oper1->ref_root > oper2->ref_root)
+ return 1;
+ return 0;
+}
+
+static int qgroup_oper_exists(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup_operation *oper)
+{
+ struct rb_node *n;
+ struct btrfs_qgroup_operation *cur;
+ int cmp;
+
+ spin_lock(&fs_info->qgroup_op_lock);
+ n = fs_info->qgroup_op_tree.rb_node;
+ while (n) {
+ cur = rb_entry(n, struct btrfs_qgroup_operation, n);
+ cmp = comp_oper_exist(cur, oper);
+ if (cmp < 0) {
+ n = n->rb_right;
+ } else if (cmp) {
+ n = n->rb_left;
+ } else {
+ spin_unlock(&fs_info->qgroup_op_lock);
+ return -EEXIST;
+ }
+ }
+ spin_unlock(&fs_info->qgroup_op_lock);
+ return 0;
+}
+
static int comp_oper(struct btrfs_qgroup_operation *oper1,
struct btrfs_qgroup_operation *oper2)
{
oper->seq = atomic_inc_return(&fs_info->qgroup_op_seq);
INIT_LIST_HEAD(&oper->elem.list);
oper->elem.seq = 0;
+
+ if (type == BTRFS_QGROUP_OPER_SUB_SUBTREE) {
+ /*
+ * If any operation for this bytenr/ref_root combo
+ * exists, then we know it's not exclusively owned and
+ * shouldn't be queued up.
+ *
+ * This also catches the case where we have a cloned
+ * extent that gets queued up multiple times during
+ * drop snapshot.
+ */
+ if (qgroup_oper_exists(fs_info, oper)) {
+ kfree(oper);
+ return 0;
+ }
+ }
+
ret = insert_qgroup_oper(fs_info, oper);
if (ret) {
/* Shouldn't happen so have an assert for developers */
return ret;
}
+/*
+ * Process a reference to a shared subtree. This type of operation is
+ * queued during snapshot removal when we encounter extents which are
+ * shared between more than one root.
+ */
+static int qgroup_subtree_accounting(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup_operation *oper)
+{
+ struct ulist *roots = NULL;
+ struct ulist_node *unode;
+ struct ulist_iterator uiter;
+ struct btrfs_qgroup_list *glist;
+ struct ulist *parents;
+ int ret = 0;
+ struct btrfs_qgroup *qg;
+ u64 root_obj = 0;
+ struct seq_list elem = {};
+
+ parents = ulist_alloc(GFP_NOFS);
+ if (!parents)
+ return -ENOMEM;
+
+ btrfs_get_tree_mod_seq(fs_info, &elem);
+ ret = btrfs_find_all_roots(trans, fs_info, oper->bytenr,
+ elem.seq, &roots);
+ btrfs_put_tree_mod_seq(fs_info, &elem);
+ if (ret < 0)
+ return ret;
+
+ if (roots->nnodes != 1)
+ goto out;
+
+ ULIST_ITER_INIT(&uiter);
+ unode = ulist_next(roots, &uiter); /* Only want 1 so no need to loop */
+ /*
+ * If we find our ref root then that means all refs
+ * this extent has to the root have not yet been
+ * deleted. In that case, we do nothing and let the
+ * last ref for this bytenr drive our update.
+ *
+ * This can happen for example if an extent is
+ * referenced multiple times in a snapshot (clone,
+ * etc). If we are in the middle of snapshot removal,
+ * queued updates for such an extent will find the
+ * root if we have not yet finished removing the
+ * snapshot.
+ */
+ if (unode->val == oper->ref_root)
+ goto out;
+
+ root_obj = unode->val;
+ BUG_ON(!root_obj);
+
+ spin_lock(&fs_info->qgroup_lock);
+ qg = find_qgroup_rb(fs_info, root_obj);
+ if (!qg)
+ goto out_unlock;
+
+ qg->excl += oper->num_bytes;
+ qg->excl_cmpr += oper->num_bytes;
+ qgroup_dirty(fs_info, qg);
+
+ /*
+ * Adjust counts for parent groups. First we find all
+ * parents, then in the 2nd loop we do the adjustment
+ * while adding parents of the parents to our ulist.
+ */
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ret = ulist_add(parents, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (ret < 0)
+ goto out_unlock;
+ }
+
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(parents, &uiter))) {
+ qg = u64_to_ptr(unode->aux);
+ qg->excl += oper->num_bytes;
+ qg->excl_cmpr += oper->num_bytes;
+ qgroup_dirty(fs_info, qg);
+
+ /* Add any parents of the parents */
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ret = ulist_add(parents, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (ret < 0)
+ goto out_unlock;
+ }
+ }
+
+out_unlock:
+ spin_unlock(&fs_info->qgroup_lock);
+
+out:
+ ulist_free(roots);
+ ulist_free(parents);
+ return ret;
+}
+
/*
* btrfs_qgroup_account_ref is called for every ref that is added to or deleted
* from the fs. First, all roots referencing the extent are searched, and
case BTRFS_QGROUP_OPER_SUB_SHARED:
ret = qgroup_shared_accounting(trans, fs_info, oper);
break;
+ case BTRFS_QGROUP_OPER_SUB_SUBTREE:
+ ret = qgroup_subtree_accounting(trans, fs_info, oper);
+ break;
default:
ASSERT(0);
}
git.samba.org / jlayton / linux.git / blobdiff