wc->reada_slot = slot;
}
+static int account_leaf_items(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *eb)
+{
+ int nr = btrfs_header_nritems(eb);
+ int i, extent_type, ret;
+ struct btrfs_key key;
+ struct btrfs_file_extent_item *fi;
+ u64 bytenr, num_bytes;
+
+ for (i = 0; i < nr; i++) {
+ btrfs_item_key_to_cpu(eb, &key, i);
+
+ if (key.type != BTRFS_EXTENT_DATA_KEY)
+ continue;
+
+ fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
+ /* filter out non qgroup-accountable extents */
+ extent_type = btrfs_file_extent_type(eb, fi);
+
+ if (extent_type == BTRFS_FILE_EXTENT_INLINE)
+ continue;
+
+ bytenr = btrfs_file_extent_disk_bytenr(eb, fi);
+ if (!bytenr)
+ continue;
+
+ num_bytes = btrfs_file_extent_disk_num_bytes(eb, fi);
+
+ ret = btrfs_qgroup_record_ref(trans, root->fs_info,
+ root->objectid,
+ bytenr, num_bytes,
+ BTRFS_QGROUP_OPER_SUB_SUBTREE, 0);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+/*
+ * Walk up the tree from the bottom, freeing leaves and any interior
+ * nodes which have had all slots visited. If a node (leaf or
+ * interior) is freed, the node above it will have it's slot
+ * incremented. The root node will never be freed.
+ *
+ * At the end of this function, we should have a path which has all
+ * slots incremented to the next position for a search. If we need to
+ * read a new node it will be NULL and the node above it will have the
+ * correct slot selected for a later read.
+ *
+ * If we increment the root nodes slot counter past the number of
+ * elements, 1 is returned to signal completion of the search.
+ */
+static int adjust_slots_upwards(struct btrfs_root *root,
+ struct btrfs_path *path, int root_level)
+{
+ int level = 0;
+ int nr, slot;
+ struct extent_buffer *eb;
+
+ if (root_level == 0)
+ return 1;
+
+ while (level <= root_level) {
+ eb = path->nodes[level];
+ nr = btrfs_header_nritems(eb);
+ path->slots[level]++;
+ slot = path->slots[level];
+ if (slot >= nr || level == 0) {
+ /*
+ * Don't free the root - we will detect this
+ * condition after our loop and return a
+ * positive value for caller to stop walking the tree.
+ */
+ if (level != root_level) {
+ btrfs_tree_unlock_rw(eb, path->locks[level]);
+ path->locks[level] = 0;
+
+ free_extent_buffer(eb);
+ path->nodes[level] = NULL;
+ path->slots[level] = 0;
+ }
+ } else {
+ /*
+ * We have a valid slot to walk back down
+ * from. Stop here so caller can process these
+ * new nodes.
+ */
+ break;
+ }
+
+ level++;
+ }
+
+ eb = path->nodes[root_level];
+ if (path->slots[root_level] >= btrfs_header_nritems(eb))
+ return 1;
+
+ return 0;
+}
+
+/*
+ * root_eb is the subtree root and is locked before this function is called.
+ */
+static int account_shared_subtree(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct extent_buffer *root_eb,
+ u64 root_gen,
+ int root_level)
+{
+ int ret = 0;
+ int level;
+ struct extent_buffer *eb = root_eb;
+ struct btrfs_path *path = NULL;
+
+ BUG_ON(root_level < 0 || root_level > BTRFS_MAX_LEVEL);
+ BUG_ON(root_eb == NULL);
+
+ if (!root->fs_info->quota_enabled)
+ return 0;
+
+ if (!extent_buffer_uptodate(root_eb)) {
+ ret = btrfs_read_buffer(root_eb, root_gen);
+ if (ret)
+ goto out;
+ }
+
+ if (root_level == 0) {
+ ret = account_leaf_items(trans, root, root_eb);
+ goto out;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ /*
+ * Walk down the tree. Missing extent blocks are filled in as
+ * we go. Metadata is accounted every time we read a new
+ * extent block.
+ *
+ * When we reach a leaf, we account for file extent items in it,
+ * walk back up the tree (adjusting slot pointers as we go)
+ * and restart the search process.
+ */
+ extent_buffer_get(root_eb); /* For path */
+ path->nodes[root_level] = root_eb;
+ path->slots[root_level] = 0;
+ path->locks[root_level] = 0; /* so release_path doesn't try to unlock */
+walk_down:
+ level = root_level;
+ while (level >= 0) {
+ if (path->nodes[level] == NULL) {
+ int child_bsize = root->nodesize;
+ int parent_slot;
+ u64 child_gen;
+ u64 child_bytenr;
+
+ /* We need to get child blockptr/gen from
+ * parent before we can read it. */
+ eb = path->nodes[level + 1];
+ parent_slot = path->slots[level + 1];
+ child_bytenr = btrfs_node_blockptr(eb, parent_slot);
+ child_gen = btrfs_node_ptr_generation(eb, parent_slot);
+
+ eb = read_tree_block(root, child_bytenr, child_bsize,
+ child_gen);
+ if (!eb || !extent_buffer_uptodate(eb)) {
+ ret = -EIO;
+ goto out;
+ }
+
+ path->nodes[level] = eb;
+ path->slots[level] = 0;
+
+ btrfs_tree_read_lock(eb);
+ btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
+ path->locks[level] = BTRFS_READ_LOCK_BLOCKING;
+
+ ret = btrfs_qgroup_record_ref(trans, root->fs_info,
+ root->objectid,
+ child_bytenr,
+ child_bsize,
+ BTRFS_QGROUP_OPER_SUB_SUBTREE,
+ 0);
+ if (ret)
+ goto out;
+
+ }
+
+ if (level == 0) {
+ ret = account_leaf_items(trans, root, path->nodes[level]);
+ if (ret)
+ goto out;
+
+ /* Nonzero return here means we completed our search */
+ ret = adjust_slots_upwards(root, path, root_level);
+ if (ret)
+ break;
+
+ /* Restart search with new slots */
+ goto walk_down;
+ }
+
+ level--;
+ }
+
+ ret = 0;
+out:
+ btrfs_free_path(path);
+
+ return ret;
+}
+
/*
* helper to process tree block while walking down the tree.
*
int level = wc->level;
int reada = 0;
int ret = 0;
+ bool need_account = false;
generation = btrfs_node_ptr_generation(path->nodes[level],
path->slots[level]);
if (wc->stage == DROP_REFERENCE) {
if (wc->refs[level - 1] > 1) {
+ need_account = true;
if (level == 1 &&
(wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
goto skip;
parent = 0;
}
+ if (need_account) {
+ ret = account_shared_subtree(trans, root, next,
+ generation, level - 1);
+ if (ret) {
+ printk_ratelimited(KERN_ERR "BTRFS: %s Error "
+ "%d accounting shared subtree. Quota "
+ "is out of sync, rescan required.\n",
+ root->fs_info->sb->s_id, ret);
+ }
+ }
ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
root->root_key.objectid, level - 1, 0, 0);
BUG_ON(ret); /* -ENOMEM */
else
ret = btrfs_dec_ref(trans, root, eb, 0);
BUG_ON(ret); /* -ENOMEM */
+ ret = account_leaf_items(trans, root, eb);
+ if (ret) {
+ printk_ratelimited(KERN_ERR "BTRFS: %s Error "
+ "%d accounting leaf items. Quota "
+ "is out of sync, rescan required.\n",
+ root->fs_info->sb->s_id, ret);
+ }
}
/* make block locked assertion in clean_tree_block happy */
if (!path->locks[level] &&
int level;
bool root_dropped = false;
+ btrfs_debug(root->fs_info, "Drop subvolume %llu", root->objectid);
+
path = btrfs_alloc_path();
if (!path) {
err = -ENOMEM;
goto out_end_trans;
}
+ /*
+ * Qgroup update accounting is run from
+ * delayed ref handling. This usually works
+ * out because delayed refs are normally the
+ * only way qgroup updates are added. However,
+ * we may have added updates during our tree
+ * walk so run qgroups here to make sure we
+ * don't lose any updates.
+ */
+ ret = btrfs_delayed_qgroup_accounting(trans,
+ root->fs_info);
+ if (ret)
+ printk_ratelimited(KERN_ERR "BTRFS: Failure %d "
+ "running qgroup updates "
+ "during snapshot delete. "
+ "Quota is out of sync, "
+ "rescan required.\n", ret);
+
btrfs_end_transaction_throttle(trans, tree_root);
if (!for_reloc && btrfs_need_cleaner_sleep(root)) {
pr_debug("BTRFS: drop snapshot early exit\n");
}
root_dropped = true;
out_end_trans:
+ ret = btrfs_delayed_qgroup_accounting(trans, tree_root->fs_info);
+ if (ret)
+ printk_ratelimited(KERN_ERR "BTRFS: Failure %d "
+ "running qgroup updates "
+ "during snapshot delete. "
+ "Quota is out of sync, "
+ "rescan required.\n", ret);
+
btrfs_end_transaction_throttle(trans, tree_root);
out_free:
kfree(wc);
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);
}
projects / users / willy / pagecache.git / commitdiff