Imported Upstream version 4.6.1

1 files changed, 1230 insertions, 0 deletions

diff --git a/qgroup-verify.c b/qgroup-verify.c
new file mode 100644
index 00000000..6ca95eb8
--- /dev/null
+++ b/qgroup-verify.c
@@ -0,0 +1,1230 @@
+/*
+ * Copyright (C) 2014 SUSE.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ *
+ * Authors: Mark Fasheh <mfasheh@suse.de>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <uuid/uuid.h>
+#include "kerncompat.h"
+#include "radix-tree.h"
+#include "ctree.h"
+#include "disk-io.h"
+#include "print-tree.h"
+#include "utils.h"
+#include "ulist.h"
+#include "rbtree-utils.h"
+
+#include "qgroup-verify.h"
+
+/*#define QGROUP_VERIFY_DEBUG*/
+static unsigned long tot_extents_scanned = 0;
+
+static void add_bytes(u64 root_objectid, u64 num_bytes, int exclusive);
+
+struct qgroup_info {
+	u64 referenced;
+	u64 referenced_compressed;
+	u64 exclusive;
+	u64 exclusive_compressed;
+};
+
+struct qgroup_count {
+	u64 qgroupid;
+	int subvol_exists;
+
+	struct btrfs_disk_key key;
+	struct qgroup_info diskinfo;
+
+	struct qgroup_info info;
+
+	struct rb_node rb_node;
+};
+
+static struct counts_tree {
+	struct rb_root		root;
+	unsigned int		num_groups;
+	unsigned int		rescan_running:1;
+	unsigned int		qgroup_inconsist:1;
+} counts = { .root = RB_ROOT };
+
+static struct rb_root by_bytenr = RB_ROOT;
+
+/*
+ * List of interior tree blocks. We walk this list after loading the
+ * extent tree to resolve implied refs. For each interior node we'll
+ * place a shared ref in the ref tree against each child object. This
+ * allows the shared ref resolving code to do the actual work later of
+ * finding roots to account against.
+ *
+ * An implied ref is when a tree block has refs on it that may not
+ * exist in any of its child nodes. Even though the refs might not
+ * exist further down the tree, the fact that our interior node has a
+ * ref means we need to account anything below it to all its roots.
+ */
+static struct ulist *tree_blocks = NULL;	/* unode->val = bytenr, ->aux
+						 * = tree_block pointer */
+struct tree_block {
+	int			level;
+	u64			num_bytes;
+};
+
+struct ref {
+	u64			bytenr;
+	u64			num_bytes;
+	u64			parent;
+	u64			root;
+
+	struct rb_node		bytenr_node;
+};
+
+#ifdef QGROUP_VERIFY_DEBUG
+static void print_ref(struct ref *ref)
+{
+	printf("bytenr: %llu\t\tnum_bytes: %llu\t\t parent: %llu\t\t"
+	       "root: %llu\n", ref->bytenr, ref->num_bytes,
+	       ref->parent, ref->root);
+}
+
+static void print_all_refs(void)
+{
+	unsigned long count = 0;
+	struct ref *ref;
+	struct rb_node *node;
+
+	node = rb_first(&by_bytenr);
+	while (node) {
+		ref = rb_entry(node, struct ref, bytenr_node);
+
+		print_ref(ref);
+
+		count++;
+		node = rb_next(node);
+	}
+
+	printf("%lu extents scanned with %lu refs in total.\n",
+	       tot_extents_scanned, count);
+}
+#endif
+
+/*
+ * Store by bytenr in rbtree
+ *
+ * The tree is sorted in ascending order by bytenr, then parent, then
+ * root. Since full refs have a parent == 0, those will come before
+ * shared refs.
+ */
+static int compare_ref(struct ref *orig, u64 bytenr, u64 root, u64 parent)
+{
+	if (bytenr < orig->bytenr)
+		return -1;
+	if (bytenr > orig->bytenr)
+		return 1;
+
+	if (parent < orig->parent)
+		return -1;
+	if (parent > orig->parent)
+		return 1;
+
+	if (root < orig->root)
+		return -1;
+	if (root > orig->root)
+		return 1;
+
+	return 0;
+}
+
+/*
+ * insert a new ref into the tree.  returns the existing ref entry
+ * if one is already there.
+ */
+static struct ref *insert_ref(struct ref *ref)
+{
+	int ret;
+	struct rb_node **p = &by_bytenr.rb_node;
+	struct rb_node *parent = NULL;
+	struct ref *curr;
+
+	while (*p) {
+		parent = *p;
+		curr = rb_entry(parent, struct ref, bytenr_node);
+
+		ret = compare_ref(curr, ref->bytenr, ref->root, ref->parent);
+		if (ret < 0)
+			p = &(*p)->rb_left;
+		else if (ret > 0)
+			p = &(*p)->rb_right;
+		else
+			return curr;
+	}
+
+	rb_link_node(&ref->bytenr_node, parent, p);
+	rb_insert_color(&ref->bytenr_node, &by_bytenr);
+	return ref;
+}
+
+/*
+ * Partial search, returns the first ref with matching bytenr. Caller
+ * can walk forward from there.
+ *
+ * Leftmost refs will be full refs - this is used to our advantage
+ * when resolving roots.
+ */
+static struct ref *find_ref_bytenr(u64 bytenr)
+{
+	struct rb_node *n = by_bytenr.rb_node;
+	struct ref *ref;
+
+	while (n) {
+		ref = rb_entry(n, struct ref, bytenr_node);
+
+		if (bytenr < ref->bytenr)
+			n = n->rb_left;
+		else if (bytenr > ref->bytenr)
+			n = n->rb_right;
+		else {
+			/* Walk to the left to find the first item */
+			struct rb_node *node_left = rb_prev(&ref->bytenr_node);
+			struct ref *ref_left;
+
+			while (node_left) {
+				ref_left = rb_entry(node_left, struct ref,
+						    bytenr_node);
+				if (ref_left->bytenr != ref->bytenr)
+					break;
+				ref = ref_left;
+				node_left = rb_prev(node_left);
+			}
+			return ref;
+		}
+	}
+	return NULL;
+}
+
+static struct ref *find_ref(u64 bytenr, u64 root, u64 parent)
+{
+	struct rb_node *n = by_bytenr.rb_node;
+	struct ref *ref;
+	int ret;
+
+	while (n) {
+		ref = rb_entry(n, struct ref, bytenr_node);
+
+		ret = compare_ref(ref, bytenr, root, parent);
+		if (ret < 0)
+			n = n->rb_left;
+		else if (ret > 0)
+			n = n->rb_right;
+		else
+			return ref;
+	}
+	return NULL;
+}
+
+static struct ref *alloc_ref(u64 bytenr, u64 root, u64 parent, u64 num_bytes)
+{
+	struct ref *ref = find_ref(bytenr, root, parent);
+
+	BUG_ON(parent && root);
+
+	if (ref == NULL) {
+		ref = calloc(1, sizeof(*ref));
+		if (ref) {
+			ref->bytenr = bytenr;
+			ref->root = root;
+			ref->parent = parent;
+			ref->num_bytes = num_bytes;
+
+			insert_ref(ref);
+		}
+	}
+	return ref;
+}
+
+static void free_ref_node(struct rb_node *node)
+{
+	struct ref *ref = rb_entry(node, struct ref, bytenr_node);
+	free(ref);
+}
+
+FREE_RB_BASED_TREE(ref, free_ref_node);
+
+/*
+ * Resolves all the possible roots for the ref at parent.
+ */
+static void find_parent_roots(struct ulist *roots, u64 parent)
+{
+	struct ref *ref;
+	struct rb_node *node;
+
+	/*
+	 * Search the rbtree for the first ref with bytenr == parent.
+	 * Walk forward so long as bytenr == parent, adding resolved root ids.
+	 * For each unresolved root, we recurse
+	 */
+	ref = find_ref_bytenr(parent);
+	node = &ref->bytenr_node;
+	BUG_ON(ref == NULL);
+	BUG_ON(ref->bytenr != parent);
+
+	{
+		/*
+		 * Random sanity check, are we actually getting the
+		 * leftmost node?
+		 */
+		struct rb_node *prev_node = rb_prev(&ref->bytenr_node);
+		struct ref *prev;
+		if (prev_node) {
+			prev = rb_entry(prev_node, struct ref, bytenr_node);
+			BUG_ON(prev->bytenr == parent);
+		}
+	}
+
+	do {
+		if (ref->root)
+			ulist_add(roots, ref->root, 0, 0);
+		else
+			find_parent_roots(roots, ref->parent);
+
+		node = rb_next(node);
+		if (node)
+			ref = rb_entry(node, struct ref, bytenr_node);
+	} while (node && ref->bytenr == parent);
+}
+
+static void print_subvol_info(u64 subvolid, u64 bytenr, u64 num_bytes,
+			      struct ulist *roots);
+/*
+ * Account each ref. Walk the refs, for each set of refs in a
+ * given bytenr:
+ *
+ * - add the roots for direct refs to the ref roots ulist
+ *
+ * - resolve all possible roots for shared refs, insert each
+ *   of those into ref_roots ulist (this is a recursive process)
+ *
+ * - Walk ref_roots ulist, adding extent bytes to each qgroup count that
+ *    cooresponds to a found root.
+ */
+static void account_all_refs(int do_qgroups, u64 search_subvol)
+{
+	int exclusive;
+	struct ref *ref;
+	struct rb_node *node;
+	u64 bytenr, num_bytes;
+	struct ulist *roots = ulist_alloc(0);
+	struct ulist_iterator uiter;
+	struct ulist_node *unode;
+
+	node = rb_first(&by_bytenr);
+	while (node) {
+		ulist_reinit(roots);
+
+		ref = rb_entry(node, struct ref, bytenr_node);
+		/*
+		 * Walk forward through the list of refs for this
+		 * bytenr, adding roots to our ulist. If it's a full
+		 * ref, then we have the easy case. Otherwise we need
+		 * to search for roots.
+		 */
+		bytenr = ref->bytenr;
+		num_bytes = ref->num_bytes;
+		do {
+			BUG_ON(ref->bytenr != bytenr);
+			BUG_ON(ref->num_bytes != num_bytes);
+			if (ref->root)
+				ulist_add(roots, ref->root, 0, 0);
+			else
+				find_parent_roots(roots, ref->parent);
+
+			/*
+			 * When we leave this inner loop, node is set
+			 * to next in our tree and will be turned into
+			 * a ref object up top
+			 */
+			node = rb_next(node);
+			if (node)
+				ref = rb_entry(node, struct ref, bytenr_node);
+		} while (node && ref->bytenr == bytenr);
+
+		/*
+		 * Now that we have all roots, we can properly account
+		 * this extent against the corresponding qgroups.
+		 */
+		if (roots->nnodes == 1)
+			exclusive = 1;
+		else
+			exclusive = 0;
+
+		if (search_subvol)
+			print_subvol_info(search_subvol, bytenr, num_bytes,
+					  roots);
+
+		ULIST_ITER_INIT(&uiter);
+		while ((unode = ulist_next(roots, &uiter))) {
+			BUG_ON(unode->val == 0ULL);
+			/* We only want to account fs trees */
+			if (is_fstree(unode->val) && do_qgroups)
+				add_bytes(unode->val, num_bytes, exclusive);
+		}
+	}
+
+	ulist_free(roots);
+}
+
+static u64 resolve_one_root(u64 bytenr)
+{
+	struct ref *ref = find_ref_bytenr(bytenr);
+
+	BUG_ON(ref == NULL);
+
+	if (ref->root)
+		return ref->root;
+	return resolve_one_root(ref->parent);
+}
+
+static inline struct tree_block *unode_tree_block(struct ulist_node *unode)
+{
+	return u64_to_ptr(unode->aux);
+}
+static inline u64 unode_bytenr(struct ulist_node *unode)
+{
+	return unode->val;
+}
+
+static int alloc_tree_block(u64 bytenr, u64 num_bytes, int level)
+{
+	struct tree_block *block = calloc(1, sizeof(*block));
+
+	if (block) {
+		block->num_bytes = num_bytes;
+		block->level = level;
+		if (ulist_add(tree_blocks, bytenr, ptr_to_u64(block), 0) >= 0)
+			return 0;
+		free(block);
+	}
+	return -ENOMEM;
+}
+
+static void free_tree_blocks(void)
+{
+	struct ulist_iterator uiter;
+	struct ulist_node *unode;
+
+	if (!tree_blocks)
+		return;
+
+	ULIST_ITER_INIT(&uiter);
+	while ((unode = ulist_next(tree_blocks, &uiter)))
+		free(unode_tree_block(unode));
+	ulist_free(tree_blocks);	
+	tree_blocks = NULL;
+}
+
+#ifdef QGROUP_VERIFY_DEBUG
+static void print_tree_block(u64 bytenr, struct tree_block *block)
+{
+	struct ref *ref;
+	struct rb_node *node;
+
+	printf("tree block: %llu\t\tlevel: %d\n", (unsigned long long)bytenr,
+	       block->level);
+
+	ref = find_ref_bytenr(bytenr);
+	node = &ref->bytenr_node;
+	do {
+		print_ref(ref);
+		node = rb_next(node);
+		if (node)
+			ref = rb_entry(node, struct ref, bytenr_node);
+	} while (node && ref->bytenr == bytenr);
+
+	printf("\n");
+}
+
+static void print_all_tree_blocks(void)
+{
+	struct ulist_iterator uiter;
+	struct ulist_node *unode;
+
+	if (!tree_blocks)
+		return;
+
+	printf("Listing all found interior tree nodes:\n");
+
+	ULIST_ITER_INIT(&uiter);
+	while ((unode = ulist_next(tree_blocks, &uiter)))
+		print_tree_block(unode_bytenr(unode), unode_tree_block(unode));
+}
+#endif
+
+static int add_refs_for_leaf_items(struct extent_buffer *eb, u64 ref_parent)
+{
+	int nr, i;
+	int extent_type;
+	u64 bytenr, num_bytes;
+	struct btrfs_key key;
+	struct btrfs_disk_key disk_key;
+	struct btrfs_file_extent_item *fi;
+
+	nr = btrfs_header_nritems(eb);
+	for (i = 0; i < nr; i++) {
+		btrfs_item_key(eb, &disk_key, i);
+		btrfs_disk_key_to_cpu(&key, &disk_key);
+
+		if (key.type != BTRFS_EXTENT_DATA_KEY)
+			continue;
+
+		fi = btrfs_item_ptr(eb, i, struct btrfs_file_extent_item);
+		/* filter out: inline, disk_bytenr == 0, compressed?
+		 * not if we can avoid it */
+		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);
+		if (alloc_ref(bytenr, 0, ref_parent, num_bytes) == NULL)
+			return ENOMEM;
+	}
+
+	return 0;
+}
+
+static int travel_tree(struct btrfs_fs_info *info, struct btrfs_root *root,
+		       u64 bytenr, u64 num_bytes, u64 ref_parent)
+{
+	int ret, nr, i;
+	struct extent_buffer *eb;
+	u64 new_bytenr;
+	u64 new_num_bytes;
+
+//	printf("travel_tree: bytenr: %llu\tnum_bytes: %llu\tref_parent: %llu\n",
+//	       bytenr, num_bytes, ref_parent);
+
+	eb = read_tree_block(root, bytenr, num_bytes, 0);
+	if (!extent_buffer_uptodate(eb))
+		return -EIO;
+
+	ret = 0;
+	/* Don't add a ref for our starting tree block to itself */
+	if (bytenr != ref_parent) {
+		if (alloc_ref(bytenr, 0, ref_parent, num_bytes) == NULL)
+			return ENOMEM;
+	}
+
+	if (btrfs_is_leaf(eb)) {
+		ret = add_refs_for_leaf_items(eb, ref_parent);
+		goto out;
+	}
+
+	/*
+	 * Interior nodes are tuples of (key, bytenr) where key is the
+	 * leftmost key in the tree block pointed to by bytenr. We
+	 * don't have to care about key here, just follow the bytenr
+	 * pointer.
+	 */
+	nr = btrfs_header_nritems(eb);
+	for (i = 0; i < nr; i++) {
+		new_bytenr = btrfs_node_blockptr(eb, i);
+		new_num_bytes = root->nodesize;
+
+		ret = travel_tree(info, root, new_bytenr, new_num_bytes,
+				  ref_parent);
+	}
+
+out:
+	free_extent_buffer(eb);
+	return ret;
+}
+
+static int add_refs_for_implied(struct btrfs_fs_info *info, u64 bytenr,
+				struct tree_block *block)
+{
+	int ret;
+	u64 root_id = resolve_one_root(bytenr);
+	struct btrfs_root *root;
+	struct btrfs_key key;
+
+	key.objectid = root_id;
+	key.type = BTRFS_ROOT_ITEM_KEY;
+	key.offset = (u64)-1;
+
+	/*
+	 * XXX: Don't free the root object as we don't know whether it
+	 * came off our fs_info struct or not.
+	 */
+	root = btrfs_read_fs_root(info, &key);
+	if (!root || IS_ERR(root))
+		return ENOENT;
+
+	ret = travel_tree(info, root, bytenr, block->num_bytes, bytenr);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+/*
+ * Place shared refs in the ref tree for each child of an interior tree node.
+ */
+static int map_implied_refs(struct btrfs_fs_info *info)
+{
+	int ret = 0;
+	struct ulist_iterator uiter;
+	struct ulist_node *unode;
+
+	ULIST_ITER_INIT(&uiter);
+	while ((unode = ulist_next(tree_blocks, &uiter))) {
+		ret = add_refs_for_implied(info, unode_bytenr(unode),
+					   unode_tree_block(unode));
+		if (ret)
+			goto out;
+	}
+out:
+	return ret;
+}
+
+/*
+ * insert a new root into the tree.  returns the existing root entry
+ * if one is already there.  qgroupid is used
+ * as the key
+ */
+static int insert_count(struct qgroup_count *qc)
+{
+	struct rb_node **p = &counts.root.rb_node;
+	struct rb_node *parent = NULL;
+	struct qgroup_count *curr;
+
+	while (*p) {
+		parent = *p;
+		curr = rb_entry(parent, struct qgroup_count, rb_node);
+
+		if (qc->qgroupid < curr->qgroupid)
+			p = &(*p)->rb_left;
+		else if (qc->qgroupid > curr->qgroupid)
+			p = &(*p)->rb_right;
+		else
+			return EEXIST;
+	}
+	counts.num_groups++;
+	rb_link_node(&qc->rb_node, parent, p);
+	rb_insert_color(&qc->rb_node, &counts.root);
+	return 0;
+}
+
+static struct qgroup_count *find_count(u64 qgroupid)
+{
+	struct rb_node *n = counts.root.rb_node;
+	struct qgroup_count *count;
+
+	while (n) {
+		count = rb_entry(n, struct qgroup_count, rb_node);
+
+		if (qgroupid < count->qgroupid)
+			n = n->rb_left;
+		else if (qgroupid > count->qgroupid)
+			n = n->rb_right;
+		else
+			return count;
+	}
+	return NULL;
+}
+
+static struct qgroup_count *alloc_count(struct btrfs_disk_key *key,
+					struct extent_buffer *leaf,
+					struct btrfs_qgroup_info_item *disk)
+{
+	struct qgroup_count *c = calloc(1, sizeof(*c));
+	struct qgroup_info *item;
+
+	if (c) {
+		c->qgroupid = btrfs_disk_key_offset(key);
+		c->key = *key;
+
+		item = &c->diskinfo;
+		item->referenced = btrfs_qgroup_info_referenced(leaf, disk);
+		item->referenced_compressed =
+			btrfs_qgroup_info_referenced_compressed(leaf, disk);
+		item->exclusive = btrfs_qgroup_info_exclusive(leaf, disk);
+		item->exclusive_compressed =
+			btrfs_qgroup_info_exclusive_compressed(leaf, disk);
+
+		if (insert_count(c)) {
+			free(c);
+			c = NULL;
+		}
+	}
+	return c;
+}
+
+static void add_bytes(u64 root_objectid, u64 num_bytes, int exclusive)
+{
+	struct qgroup_count *count = find_count(root_objectid);
+	struct qgroup_info *qg;
+
+	BUG_ON(num_bytes < 4096); /* Random sanity check. */
+
+	if (!count)
+		return;
+
+	qg = &count->info;
+
+	qg->referenced += num_bytes;
+	/*
+	 * count of compressed bytes is unimplemented, so we do the
+	 * same as kernel.
+	 */
+	qg->referenced_compressed += num_bytes;
+
+	if (exclusive) {
+		qg->exclusive += num_bytes;
+		qg->exclusive_compressed += num_bytes;
+	}
+}
+
+static void read_qgroup_status(struct btrfs_path *path,
+			      struct counts_tree *counts)
+{
+	struct btrfs_qgroup_status_item *status_item;
+	u64 flags;
+
+	status_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
+				     struct btrfs_qgroup_status_item);
+	flags = btrfs_qgroup_status_flags(path->nodes[0], status_item);
+	/*
+	 * Since qgroup_inconsist/rescan_running is just one bit,
+	 * assign value directly won't work.
+	 */
+	counts->qgroup_inconsist = !!(flags &
+			BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT);
+	counts->rescan_running = !!(flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN);
+}
+
+static int load_quota_info(struct btrfs_fs_info *info)
+{
+	int ret;
+	struct btrfs_root *root = info->quota_root;
+	struct btrfs_root *tmproot;
+	struct btrfs_path path;
+	struct btrfs_key key;
+	struct btrfs_key root_key;
+	struct btrfs_disk_key disk_key;
+	struct extent_buffer *leaf;
+	struct btrfs_qgroup_info_item *item;
+	struct qgroup_count *count;
+	int i, nr;
+
+	btrfs_init_path(&path);
+
+	key.offset = 0;
+	key.objectid = 0;
+	key.type = 0;
+
+	ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
+	if (ret < 0) {
+		fprintf(stderr, "ERROR: Couldn't search slot: %d\n", ret);
+		goto out;
+	}
+
+	while (1) {
+		leaf = path.nodes[0];
+
+		nr = btrfs_header_nritems(leaf);
+		for(i = 0; i < nr; i++) {
+			btrfs_item_key(leaf, &disk_key, i);
+			btrfs_disk_key_to_cpu(&key, &disk_key);
+
+			if (key.type == BTRFS_QGROUP_STATUS_KEY) {
+				read_qgroup_status(&path, &counts);
+				continue;
+			}
+			if (key.type == BTRFS_QGROUP_RELATION_KEY)
+				printf("Ignoring qgroup relation key %llu\n",
+				       key.objectid);
+
+			/*
+			 * Ignore: BTRFS_QGROUP_LIMIT_KEY,
+			 * 	   BTRFS_QGROUP_RELATION_KEY
+			 */
+			if (key.type != BTRFS_QGROUP_INFO_KEY)
+				continue;
+
+			item = btrfs_item_ptr(leaf, i,
+					      struct btrfs_qgroup_info_item);
+
+			count = alloc_count(&disk_key, leaf, item);
+			if (!count) {
+				ret = ENOMEM;
+				fprintf(stderr, "ERROR: out of memory\n");
+				goto out;
+			}
+
+			root_key.objectid = key.offset;
+			root_key.type = BTRFS_ROOT_ITEM_KEY;
+			root_key.offset = (u64)-1;
+			tmproot = btrfs_read_fs_root_no_cache(info, &root_key);
+			if (tmproot && !IS_ERR(tmproot)) {
+				count->subvol_exists = 1;
+				btrfs_free_fs_root(tmproot);
+			}
+		}
+
+		ret = btrfs_next_leaf(root, &path);
+		if (ret != 0)
+			break;
+	}
+
+	ret = 0;
+	btrfs_release_path(&path);
+out:
+	return ret;
+}
+
+static int add_inline_refs(struct btrfs_fs_info *info,
+			   struct extent_buffer *ei_leaf, int slot,
+			   u64 bytenr, u64 num_bytes, int meta_item)
+{
+	struct btrfs_extent_item *ei;
+	struct btrfs_extent_inline_ref *iref;
+	struct btrfs_extent_data_ref *dref;
+	u64 flags, root_obj, offset, parent;
+	u32 item_size = btrfs_item_size_nr(ei_leaf, slot);
+	int type;
+	unsigned long end;
+	unsigned long ptr;
+
+	ei = btrfs_item_ptr(ei_leaf, slot, struct btrfs_extent_item);
+	flags = btrfs_extent_flags(ei_leaf, ei);
+
+	if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !meta_item) {
+		struct btrfs_tree_block_info *tbinfo;
+		tbinfo = (struct btrfs_tree_block_info *)(ei + 1);
+		iref = (struct btrfs_extent_inline_ref *)(tbinfo + 1);
+	} else {
+		iref = (struct btrfs_extent_inline_ref *)(ei + 1);
+	}
+
+	ptr = (unsigned long)iref;
+	end = (unsigned long)ei + item_size;
+	while (ptr < end) {
+		iref = (struct btrfs_extent_inline_ref *)ptr;
+
+		parent = root_obj = 0;
+		offset = btrfs_extent_inline_ref_offset(ei_leaf, iref);
+		type = btrfs_extent_inline_ref_type(ei_leaf, iref);
+		switch (type) {
+		case BTRFS_TREE_BLOCK_REF_KEY:
+			root_obj = offset;
+			break;
+		case BTRFS_EXTENT_DATA_REF_KEY:
+			dref = (struct btrfs_extent_data_ref *)(&iref->offset);
+			root_obj = btrfs_extent_data_ref_root(ei_leaf, dref);
+			break;
+		case BTRFS_SHARED_DATA_REF_KEY:
+		case BTRFS_SHARED_BLOCK_REF_KEY:
+			parent = offset;
+			break;
+		default:
+			return 1;
+		}
+
+		if (alloc_ref(bytenr, root_obj, parent, num_bytes) == NULL)
+			return ENOMEM;
+
+		ptr += btrfs_extent_inline_ref_size(type);
+	}
+
+	return 0;
+}
+
+static int add_keyed_ref(struct btrfs_fs_info *info,
+			 struct btrfs_key *key,
+			 struct extent_buffer *leaf, int slot,
+			 u64 bytenr, u64 num_bytes)
+{
+	u64 root_obj = 0, parent = 0;
+	struct btrfs_extent_data_ref *dref;
+
+	switch(key->type) {
+	case BTRFS_TREE_BLOCK_REF_KEY:
+		root_obj = key->offset;
+		break;
+	case BTRFS_EXTENT_DATA_REF_KEY:
+		dref = btrfs_item_ptr(leaf, slot, struct btrfs_extent_data_ref);
+		root_obj = btrfs_extent_data_ref_root(leaf, dref);
+		break;
+	case BTRFS_SHARED_DATA_REF_KEY:
+	case BTRFS_SHARED_BLOCK_REF_KEY:
+		parent = key->offset;
+		break;
+	default:
+		return 1;
+	}
+
+	if (alloc_ref(bytenr, root_obj, parent, num_bytes) == NULL)
+		return ENOMEM;
+
+	return 0;
+}
+
+/*
+ * return value of 0 indicates leaf or not meta data. The code that
+ * calls this does not need to make a distinction between the two as
+ * it is only concerned with intermediate blocks which will always
+ * have level > 0.
+ */
+static int get_tree_block_level(struct btrfs_key *key,
+				struct extent_buffer *ei_leaf,
+				int slot)
+{
+	int level = 0;
+	int meta_key = key->type == BTRFS_METADATA_ITEM_KEY;
+	u64 flags;
+	struct btrfs_extent_item *ei;
+
+	ei = btrfs_item_ptr(ei_leaf, slot, struct btrfs_extent_item);
+	flags = btrfs_extent_flags(ei_leaf, ei);
+
+	if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK && !meta_key) {
+		struct btrfs_tree_block_info *tbinfo;
+		tbinfo = (struct btrfs_tree_block_info *)(ei + 1);
+		level = btrfs_tree_block_level(ei_leaf, tbinfo);
+	} else if (meta_key) {
+		/* skinny metadata */
+		level = (int)key->offset;
+	}
+	return level;
+}
+
+/*
+ * Walk the extent tree, allocating a ref item for every ref and
+ * storing it in the bytenr tree.
+ */
+static int scan_extents(struct btrfs_fs_info *info,
+			u64 start, u64 end)
+{
+	int ret, i, nr, level;
+	struct btrfs_root *root = info->extent_root;
+	struct btrfs_key key;
+	struct btrfs_path path;
+	struct btrfs_disk_key disk_key;
+	struct extent_buffer *leaf;
+	u64 bytenr = 0, num_bytes = 0;
+
+	btrfs_init_path(&path);
+
+	key.objectid = start;
+	key.type = 0;
+	key.offset = 0;
+
+	ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
+	if (ret < 0) {
+		fprintf(stderr, "ERROR: Couldn't search slot: %d\n", ret);
+		goto out;
+	}
+	path.reada = 1;
+
+	while (1) {
+		leaf = path.nodes[0];
+
+		nr = btrfs_header_nritems(leaf);
+		for(i = 0; i < nr; i++) {
+			btrfs_item_key(leaf, &disk_key, i);
+			btrfs_disk_key_to_cpu(&key, &disk_key);
+
+			if (key.objectid < start)
+				continue;
+
+			if (key.objectid > end)
+				goto done;
+
+			if (key.type == BTRFS_EXTENT_ITEM_KEY ||
+			    key.type == BTRFS_METADATA_ITEM_KEY) {
+				int meta = 0;
+
+				tot_extents_scanned++;
+
+				bytenr = key.objectid;
+				num_bytes = key.offset;
+				if (key.type == BTRFS_METADATA_ITEM_KEY) {
+					num_bytes = info->extent_root->nodesize;
+					meta = 1;
+				}
+
+				ret = add_inline_refs(info, leaf, i, bytenr,
+						      num_bytes, meta);
+				if (ret)
+					goto out;
+
+				level = get_tree_block_level(&key, leaf, i);
+				if (level) {
+					if (alloc_tree_block(bytenr, num_bytes,
+							     level))
+						return ENOMEM;
+				}
+
+				continue;
+			}
+
+			if (key.type > BTRFS_SHARED_DATA_REF_KEY)
+				continue;
+			if (key.type < BTRFS_TREE_BLOCK_REF_KEY)
+				continue;
+
+			/*
+			 * Keyed refs should come after their extent
+			 * item in the tree. As a result, the value of
+			 * bytenr and num_bytes should be unchanged
+			 * from the above block that catches the
+			 * original extent item.
+			 */
+			BUG_ON(key.objectid != bytenr);
+
+			ret = add_keyed_ref(info, &key, leaf, i, bytenr,
+					    num_bytes);
+			if (ret)
+				goto out;
+		}
+
+		ret = btrfs_next_leaf(root, &path);
+		if (ret != 0) {
+			if (ret < 0) {
+				fprintf(stderr,
+					"ERROR: Next leaf failed: %d\n", ret);
+				goto out;
+			}
+			break;
+		}
+	}
+done:
+	ret = 0;
+out:
+	btrfs_release_path(&path);
+
+	return ret;
+}
+
+static void print_fields(u64 bytes, u64 bytes_compressed, char *prefix,
+			 char *type)
+{
+	printf("%s\t\t%s %llu %s compressed %llu\n",
+	       prefix, type, (unsigned long long)bytes, type,
+	       (unsigned long long)bytes_compressed);
+}
+
+static void print_fields_signed(long long bytes,
+				long long bytes_compressed,
+				char *prefix, char *type)
+{
+	printf("%s\t\t%s %lld %s compressed %lld\n",
+	       prefix, type, bytes, type, bytes_compressed);
+}
+
+static int report_qgroup_difference(struct qgroup_count *count, int verbose)
+{
+	int is_different;
+	struct qgroup_info *info = &count->info;
+	struct qgroup_info *disk = &count->diskinfo;
+	long long excl_diff = info->exclusive - disk->exclusive;
+	long long ref_diff = info->referenced - disk->referenced;
+
+	is_different = excl_diff || ref_diff;
+
+	if (verbose || (is_different && count->subvol_exists)) {
+		printf("Counts for qgroup id: %llu %s\n",
+		       (unsigned long long)count->qgroupid,
+		       is_different ? "are different" : "");
+
+		print_fields(info->referenced, info->referenced_compressed,
+			     "our:", "referenced");
+		print_fields(disk->referenced, disk->referenced_compressed,
+			     "disk:", "referenced");
+		if (ref_diff)
+			print_fields_signed(ref_diff, ref_diff,
+					    "diff:", "referenced");
+		print_fields(info->exclusive, info->exclusive_compressed,
+			     "our:", "exclusive");
+		print_fields(disk->exclusive, disk->exclusive_compressed,
+			     "disk:", "exclusive");
+		if (excl_diff)
+			print_fields_signed(excl_diff, excl_diff,
+					    "diff:", "exclusive");
+	}
+	return (is_different && count->subvol_exists);
+}
+
+int report_qgroups(int all)
+{
+	struct rb_node *node;
+	struct qgroup_count *c;
+	int ret = 0;
+
+	if (counts.rescan_running) {
+		if (all) {
+			printf(
+	"Qgroup rescan is running, qgroup counts difference is expected\n");
+		} else {
+			printf(
+	"Qgroup rescan is running, ignore qgroup check\n");
+			return ret;
+		}
+	}
+	if (counts.qgroup_inconsist && !counts.rescan_running)
+		fprintf(stderr, "Qgroup is already inconsistent before checking\n");
+	node = rb_first(&counts.root);
+	while (node) {
+		c = rb_entry(node, struct qgroup_count, rb_node);
+		ret |= report_qgroup_difference(c, all);
+		node = rb_next(node);
+	}
+	return ret;
+}
+
+void free_qgroup_counts(void)
+{
+	struct rb_node *node;
+	struct qgroup_count *c;
+	node = rb_first(&counts.root);
+	while (node) {
+		c = rb_entry(node, struct qgroup_count, rb_node);
+		node = rb_next(node);
+		rb_erase(&c->rb_node, &counts.root);
+		free(c);
+	}
+}
+
+int qgroup_verify_all(struct btrfs_fs_info *info)
+{
+	int ret;
+
+	if (!info->quota_enabled)
+		return 0;
+
+	tree_blocks = ulist_alloc(0);
+	if (!tree_blocks) {
+		fprintf(stderr,
+			"ERROR: Out of memory while allocating ulist.\n");
+		return ENOMEM;
+	}
+
+	ret = load_quota_info(info);
+	if (ret) {
+		fprintf(stderr, "ERROR: Loading qgroups from disk: %d\n", ret);
+		goto out;
+	}
+
+	/*
+	 * Put all extent refs into our rbtree
+	 */
+	ret = scan_extents(info, 0, ~0ULL);
+	if (ret) {
+		fprintf(stderr, "ERROR: while scanning extent tree: %d\n", ret);
+		goto out;
+	}
+
+	ret = map_implied_refs(info);
+	if (ret) {
+		fprintf(stderr, "ERROR: while mapping refs: %d\n", ret);
+		goto out;
+	}
+
+	account_all_refs(1, 0);
+
+out:
+	/*
+	 * Don't free the qgroup count records as they will be walked
+	 * later via the print function.
+	 */
+	free_tree_blocks();
+	free_ref_tree(&by_bytenr);
+	return ret;
+}
+
+static void __print_subvol_info(u64 bytenr, u64 num_bytes, struct ulist *roots)
+{
+	int n = roots->nnodes;
+	struct ulist_iterator uiter;
+	struct ulist_node *unode;
+
+	printf("%llu\t%llu\t%d\t", bytenr, num_bytes, n);
+
+	ULIST_ITER_INIT(&uiter);
+	while ((unode = ulist_next(roots, &uiter))) {
+		printf("%llu ", unode->val);
+	}
+	printf("\n");
+}
+
+static void print_subvol_info(u64 subvolid, u64 bytenr, u64 num_bytes,
+			      struct ulist *roots)
+{
+	struct ulist_iterator uiter;
+	struct ulist_node *unode;
+
+	ULIST_ITER_INIT(&uiter);
+	while ((unode = ulist_next(roots, &uiter))) {
+		BUG_ON(unode->val == 0ULL);
+		if (unode->val == subvolid) {
+			__print_subvol_info(bytenr, num_bytes, roots);
+			return;
+		}
+	}
+
+
+}
+
+int print_extent_state(struct btrfs_fs_info *info, u64 subvol)
+{
+	int ret;
+
+	tree_blocks = ulist_alloc(0);
+	if (!tree_blocks) {
+		fprintf(stderr,
+			"ERROR: Out of memory while allocating ulist.\n");
+		return ENOMEM;
+	}
+
+	/*
+	 * Put all extent refs into our rbtree
+	 */
+	ret = scan_extents(info, 0, ~0ULL);
+	if (ret) {
+		fprintf(stderr, "ERROR: while scanning extent tree: %d\n", ret);
+		goto out;
+	}
+
+	ret = map_implied_refs(info);
+	if (ret) {
+		fprintf(stderr, "ERROR: while mapping refs: %d\n", ret);
+		goto out;
+	}
+
+	printf("Offset\t\tLen\tRoot Refs\tRoots\n");
+	account_all_refs(0, subvol);
+
+out:
+	free_tree_blocks();
+	free_ref_tree(&by_bytenr);
+	return ret;
+}
+