--- /dev/null
+/*
+ * Copyright (C) 2011 STRATO. 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.
+ */
+
+#include <linux/sched.h>
+#include <linux/pagemap.h>
+#include <linux/writeback.h>
+#include <linux/blkdev.h>
+#include <linux/rbtree.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/btrfs.h>
+
+#include "ctree.h"
+#include "transaction.h"
+#include "disk-io.h"
+#include "locking.h"
+#include "ulist.h"
+#include "backref.h"
+#include "extent_io.h"
+#include "qgroup.h"
+
+/* TODO XXX FIXME
+ * - subvol delete -> delete when ref goes to 0? delete limits also?
+ * - reorganize keys
+ * - compressed
+ * - sync
+ * - copy also limits on subvol creation
+ * - limit
+ * - caches fuer ulists
+ * - performance benchmarks
+ * - check all ioctl parameters
+ */
+
+/*
+ * one struct for each qgroup, organized in fs_info->qgroup_tree.
+ */
+struct btrfs_qgroup {
+ u64 qgroupid;
+
+ /*
+ * state
+ */
+ u64 rfer; /* referenced */
+ u64 rfer_cmpr; /* referenced compressed */
+ u64 excl; /* exclusive */
+ u64 excl_cmpr; /* exclusive compressed */
+
+ /*
+ * limits
+ */
+ u64 lim_flags; /* which limits are set */
+ u64 max_rfer;
+ u64 max_excl;
+ u64 rsv_rfer;
+ u64 rsv_excl;
+
+ /*
+ * reservation tracking
+ */
+ u64 reserved;
+
+ /*
+ * lists
+ */
+ struct list_head groups; /* groups this group is member of */
+ struct list_head members; /* groups that are members of this group */
+ struct list_head dirty; /* dirty groups */
+ struct rb_node node; /* tree of qgroups */
+
+ /*
+ * temp variables for accounting operations
+ */
+ u64 old_refcnt;
+ u64 new_refcnt;
+};
+
+/*
+ * glue structure to represent the relations between qgroups.
+ */
+struct btrfs_qgroup_list {
+ struct list_head next_group;
+ struct list_head next_member;
+ struct btrfs_qgroup *group;
+ struct btrfs_qgroup *member;
+};
+
+#define ptr_to_u64(x) ((u64)(uintptr_t)x)
+#define u64_to_ptr(x) ((struct btrfs_qgroup *)(uintptr_t)x)
+
+static int
+qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
+ int init_flags);
+static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
+
+/* must be called with qgroup_ioctl_lock held */
+static struct btrfs_qgroup *find_qgroup_rb(struct btrfs_fs_info *fs_info,
+ u64 qgroupid)
+{
+ struct rb_node *n = fs_info->qgroup_tree.rb_node;
+ struct btrfs_qgroup *qgroup;
+
+ while (n) {
+ qgroup = rb_entry(n, struct btrfs_qgroup, node);
+ if (qgroup->qgroupid < qgroupid)
+ n = n->rb_left;
+ else if (qgroup->qgroupid > qgroupid)
+ n = n->rb_right;
+ else
+ return qgroup;
+ }
+ return NULL;
+}
+
+/* must be called with qgroup_lock held */
+static struct btrfs_qgroup *add_qgroup_rb(struct btrfs_fs_info *fs_info,
+ u64 qgroupid)
+{
+ struct rb_node **p = &fs_info->qgroup_tree.rb_node;
+ struct rb_node *parent = NULL;
+ struct btrfs_qgroup *qgroup;
+
+ while (*p) {
+ parent = *p;
+ qgroup = rb_entry(parent, struct btrfs_qgroup, node);
+
+ if (qgroup->qgroupid < qgroupid)
+ p = &(*p)->rb_left;
+ else if (qgroup->qgroupid > qgroupid)
+ p = &(*p)->rb_right;
+ else
+ return qgroup;
+ }
+
+ qgroup = kzalloc(sizeof(*qgroup), GFP_ATOMIC);
+ if (!qgroup)
+ return ERR_PTR(-ENOMEM);
+
+ qgroup->qgroupid = qgroupid;
+ INIT_LIST_HEAD(&qgroup->groups);
+ INIT_LIST_HEAD(&qgroup->members);
+ INIT_LIST_HEAD(&qgroup->dirty);
+
+ rb_link_node(&qgroup->node, parent, p);
+ rb_insert_color(&qgroup->node, &fs_info->qgroup_tree);
+
+ return qgroup;
+}
+
+static void __del_qgroup_rb(struct btrfs_qgroup *qgroup)
+{
+ struct btrfs_qgroup_list *list;
+
+ list_del(&qgroup->dirty);
+ while (!list_empty(&qgroup->groups)) {
+ list = list_first_entry(&qgroup->groups,
+ struct btrfs_qgroup_list, next_group);
+ list_del(&list->next_group);
+ list_del(&list->next_member);
+ kfree(list);
+ }
+
+ while (!list_empty(&qgroup->members)) {
+ list = list_first_entry(&qgroup->members,
+ struct btrfs_qgroup_list, next_member);
+ list_del(&list->next_group);
+ list_del(&list->next_member);
+ kfree(list);
+ }
+ kfree(qgroup);
+}
+
+/* must be called with qgroup_lock held */
+static int del_qgroup_rb(struct btrfs_fs_info *fs_info, u64 qgroupid)
+{
+ struct btrfs_qgroup *qgroup = find_qgroup_rb(fs_info, qgroupid);
+
+ if (!qgroup)
+ return -ENOENT;
+
+ rb_erase(&qgroup->node, &fs_info->qgroup_tree);
+ __del_qgroup_rb(qgroup);
+ return 0;
+}
+
+/* must be called with qgroup_lock held */
+static int add_relation_rb(struct btrfs_fs_info *fs_info,
+ u64 memberid, u64 parentid)
+{
+ struct btrfs_qgroup *member;
+ struct btrfs_qgroup *parent;
+ struct btrfs_qgroup_list *list;
+
+ member = find_qgroup_rb(fs_info, memberid);
+ parent = find_qgroup_rb(fs_info, parentid);
+ if (!member || !parent)
+ return -ENOENT;
+
+ list = kzalloc(sizeof(*list), GFP_ATOMIC);
+ if (!list)
+ return -ENOMEM;
+
+ list->group = parent;
+ list->member = member;
+ list_add_tail(&list->next_group, &member->groups);
+ list_add_tail(&list->next_member, &parent->members);
+
+ return 0;
+}
+
+/* must be called with qgroup_lock held */
+static int del_relation_rb(struct btrfs_fs_info *fs_info,
+ u64 memberid, u64 parentid)
+{
+ struct btrfs_qgroup *member;
+ struct btrfs_qgroup *parent;
+ struct btrfs_qgroup_list *list;
+
+ member = find_qgroup_rb(fs_info, memberid);
+ parent = find_qgroup_rb(fs_info, parentid);
+ if (!member || !parent)
+ return -ENOENT;
+
+ list_for_each_entry(list, &member->groups, next_group) {
+ if (list->group == parent) {
+ list_del(&list->next_group);
+ list_del(&list->next_member);
+ kfree(list);
+ return 0;
+ }
+ }
+ return -ENOENT;
+}
+
+#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
+int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
+ u64 rfer, u64 excl)
+{
+ struct btrfs_qgroup *qgroup;
+
+ qgroup = find_qgroup_rb(fs_info, qgroupid);
+ if (!qgroup)
+ return -EINVAL;
+ if (qgroup->rfer != rfer || qgroup->excl != excl)
+ return -EINVAL;
+ return 0;
+}
+#endif
+
+/*
+ * The full config is read in one go, only called from open_ctree()
+ * It doesn't use any locking, as at this point we're still single-threaded
+ */
+int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ struct btrfs_root *quota_root = fs_info->quota_root;
+ struct btrfs_path *path = NULL;
+ struct extent_buffer *l;
+ int slot;
+ int ret = 0;
+ u64 flags = 0;
+ u64 rescan_progress = 0;
+
+ if (!fs_info->quota_enabled)
+ return 0;
+
+ fs_info->qgroup_ulist = ulist_alloc(GFP_NOFS);
+ if (!fs_info->qgroup_ulist) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ /* default this to quota off, in case no status key is found */
+ fs_info->qgroup_flags = 0;
+
+ /*
+ * pass 1: read status, all qgroup infos and limits
+ */
+ key.objectid = 0;
+ key.type = 0;
+ key.offset = 0;
+ ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 1);
+ if (ret)
+ goto out;
+
+ while (1) {
+ struct btrfs_qgroup *qgroup;
+
+ slot = path->slots[0];
+ l = path->nodes[0];
+ btrfs_item_key_to_cpu(l, &found_key, slot);
+
+ if (found_key.type == BTRFS_QGROUP_STATUS_KEY) {
+ struct btrfs_qgroup_status_item *ptr;
+
+ ptr = btrfs_item_ptr(l, slot,
+ struct btrfs_qgroup_status_item);
+
+ if (btrfs_qgroup_status_version(l, ptr) !=
+ BTRFS_QGROUP_STATUS_VERSION) {
+ btrfs_err(fs_info,
+ "old qgroup version, quota disabled");
+ goto out;
+ }
+ if (btrfs_qgroup_status_generation(l, ptr) !=
+ fs_info->generation) {
+ flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ btrfs_err(fs_info,
+ "qgroup generation mismatch, "
+ "marked as inconsistent");
+ }
+ fs_info->qgroup_flags = btrfs_qgroup_status_flags(l,
+ ptr);
+ rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
+ goto next1;
+ }
+
+ if (found_key.type != BTRFS_QGROUP_INFO_KEY &&
+ found_key.type != BTRFS_QGROUP_LIMIT_KEY)
+ goto next1;
+
+ qgroup = find_qgroup_rb(fs_info, found_key.offset);
+ if ((qgroup && found_key.type == BTRFS_QGROUP_INFO_KEY) ||
+ (!qgroup && found_key.type == BTRFS_QGROUP_LIMIT_KEY)) {
+ btrfs_err(fs_info, "inconsitent qgroup config");
+ flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ }
+ if (!qgroup) {
+ qgroup = add_qgroup_rb(fs_info, found_key.offset);
+ if (IS_ERR(qgroup)) {
+ ret = PTR_ERR(qgroup);
+ goto out;
+ }
+ }
+ switch (found_key.type) {
+ case BTRFS_QGROUP_INFO_KEY: {
+ struct btrfs_qgroup_info_item *ptr;
+
+ ptr = btrfs_item_ptr(l, slot,
+ struct btrfs_qgroup_info_item);
+ qgroup->rfer = btrfs_qgroup_info_rfer(l, ptr);
+ qgroup->rfer_cmpr = btrfs_qgroup_info_rfer_cmpr(l, ptr);
+ qgroup->excl = btrfs_qgroup_info_excl(l, ptr);
+ qgroup->excl_cmpr = btrfs_qgroup_info_excl_cmpr(l, ptr);
+ /* generation currently unused */
+ break;
+ }
+ case BTRFS_QGROUP_LIMIT_KEY: {
+ struct btrfs_qgroup_limit_item *ptr;
+
+ ptr = btrfs_item_ptr(l, slot,
+ struct btrfs_qgroup_limit_item);
+ qgroup->lim_flags = btrfs_qgroup_limit_flags(l, ptr);
+ qgroup->max_rfer = btrfs_qgroup_limit_max_rfer(l, ptr);
+ qgroup->max_excl = btrfs_qgroup_limit_max_excl(l, ptr);
+ qgroup->rsv_rfer = btrfs_qgroup_limit_rsv_rfer(l, ptr);
+ qgroup->rsv_excl = btrfs_qgroup_limit_rsv_excl(l, ptr);
+ break;
+ }
+ }
+next1:
+ ret = btrfs_next_item(quota_root, path);
+ if (ret < 0)
+ goto out;
+ if (ret)
+ break;
+ }
+ btrfs_release_path(path);
+
+ /*
+ * pass 2: read all qgroup relations
+ */
+ key.objectid = 0;
+ key.type = BTRFS_QGROUP_RELATION_KEY;
+ key.offset = 0;
+ ret = btrfs_search_slot_for_read(quota_root, &key, path, 1, 0);
+ if (ret)
+ goto out;
+ while (1) {
+ slot = path->slots[0];
+ l = path->nodes[0];
+ btrfs_item_key_to_cpu(l, &found_key, slot);
+
+ if (found_key.type != BTRFS_QGROUP_RELATION_KEY)
+ goto next2;
+
+ if (found_key.objectid > found_key.offset) {
+ /* parent <- member, not needed to build config */
+ /* FIXME should we omit the key completely? */
+ goto next2;
+ }
+
+ ret = add_relation_rb(fs_info, found_key.objectid,
+ found_key.offset);
+ if (ret == -ENOENT) {
+ btrfs_warn(fs_info,
+ "orphan qgroup relation 0x%llx->0x%llx",
+ found_key.objectid, found_key.offset);
+ ret = 0; /* ignore the error */
+ }
+ if (ret)
+ goto out;
+next2:
+ ret = btrfs_next_item(quota_root, path);
+ if (ret < 0)
+ goto out;
+ if (ret)
+ break;
+ }
+out:
+ fs_info->qgroup_flags |= flags;
+ if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON)) {
+ fs_info->quota_enabled = 0;
+ fs_info->pending_quota_state = 0;
+ } else if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN &&
+ ret >= 0) {
+ ret = qgroup_rescan_init(fs_info, rescan_progress, 0);
+ }
+ btrfs_free_path(path);
+
+ if (ret < 0) {
+ ulist_free(fs_info->qgroup_ulist);
+ fs_info->qgroup_ulist = NULL;
+ fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
+ }
+
+ return ret < 0 ? ret : 0;
+}
+
+/*
+ * This is called from close_ctree() or open_ctree() or btrfs_quota_disable(),
+ * first two are in single-threaded paths.And for the third one, we have set
+ * quota_root to be null with qgroup_lock held before, so it is safe to clean
+ * up the in-memory structures without qgroup_lock held.
+ */
+void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
+{
+ struct rb_node *n;
+ struct btrfs_qgroup *qgroup;
+
+ while ((n = rb_first(&fs_info->qgroup_tree))) {
+ qgroup = rb_entry(n, struct btrfs_qgroup, node);
+ rb_erase(n, &fs_info->qgroup_tree);
+ __del_qgroup_rb(qgroup);
+ }
+ /*
+ * we call btrfs_free_qgroup_config() when umounting
+ * filesystem and disabling quota, so we set qgroup_ulit
+ * to be null here to avoid double free.
+ */
+ ulist_free(fs_info->qgroup_ulist);
+ fs_info->qgroup_ulist = NULL;
+}
+
+static int add_qgroup_relation_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *quota_root,
+ u64 src, u64 dst)
+{
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = src;
+ key.type = BTRFS_QGROUP_RELATION_KEY;
+ key.offset = dst;
+
+ ret = btrfs_insert_empty_item(trans, quota_root, path, &key, 0);
+
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int del_qgroup_relation_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *quota_root,
+ u64 src, u64 dst)
+{
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = src;
+ key.type = BTRFS_QGROUP_RELATION_KEY;
+ key.offset = dst;
+
+ ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
+ if (ret < 0)
+ goto out;
+
+ if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ ret = btrfs_del_item(trans, quota_root, path);
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int add_qgroup_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *quota_root, u64 qgroupid)
+{
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_qgroup_info_item *qgroup_info;
+ struct btrfs_qgroup_limit_item *qgroup_limit;
+ struct extent_buffer *leaf;
+ struct btrfs_key key;
+
+ if (btrfs_test_is_dummy_root(quota_root))
+ return 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = 0;
+ key.type = BTRFS_QGROUP_INFO_KEY;
+ key.offset = qgroupid;
+
+ /*
+ * Avoid a transaction abort by catching -EEXIST here. In that
+ * case, we proceed by re-initializing the existing structure
+ * on disk.
+ */
+
+ ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
+ sizeof(*qgroup_info));
+ if (ret && ret != -EEXIST)
+ goto out;
+
+ leaf = path->nodes[0];
+ qgroup_info = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_qgroup_info_item);
+ btrfs_set_qgroup_info_generation(leaf, qgroup_info, trans->transid);
+ btrfs_set_qgroup_info_rfer(leaf, qgroup_info, 0);
+ btrfs_set_qgroup_info_rfer_cmpr(leaf, qgroup_info, 0);
+ btrfs_set_qgroup_info_excl(leaf, qgroup_info, 0);
+ btrfs_set_qgroup_info_excl_cmpr(leaf, qgroup_info, 0);
+
+ btrfs_mark_buffer_dirty(leaf);
+
+ btrfs_release_path(path);
+
+ key.type = BTRFS_QGROUP_LIMIT_KEY;
+ ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
+ sizeof(*qgroup_limit));
+ if (ret && ret != -EEXIST)
+ goto out;
+
+ leaf = path->nodes[0];
+ qgroup_limit = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_qgroup_limit_item);
+ btrfs_set_qgroup_limit_flags(leaf, qgroup_limit, 0);
+ btrfs_set_qgroup_limit_max_rfer(leaf, qgroup_limit, 0);
+ btrfs_set_qgroup_limit_max_excl(leaf, qgroup_limit, 0);
+ btrfs_set_qgroup_limit_rsv_rfer(leaf, qgroup_limit, 0);
+ btrfs_set_qgroup_limit_rsv_excl(leaf, qgroup_limit, 0);
+
+ btrfs_mark_buffer_dirty(leaf);
+
+ ret = 0;
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int del_qgroup_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *quota_root, u64 qgroupid)
+{
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = 0;
+ key.type = BTRFS_QGROUP_INFO_KEY;
+ key.offset = qgroupid;
+ ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
+ if (ret < 0)
+ goto out;
+
+ if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ ret = btrfs_del_item(trans, quota_root, path);
+ if (ret)
+ goto out;
+
+ btrfs_release_path(path);
+
+ key.type = BTRFS_QGROUP_LIMIT_KEY;
+ ret = btrfs_search_slot(trans, quota_root, &key, path, -1, 1);
+ if (ret < 0)
+ goto out;
+
+ if (ret > 0) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ ret = btrfs_del_item(trans, quota_root, path);
+
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int update_qgroup_limit_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_qgroup *qgroup)
+{
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct extent_buffer *l;
+ struct btrfs_qgroup_limit_item *qgroup_limit;
+ int ret;
+ int slot;
+
+ key.objectid = 0;
+ key.type = BTRFS_QGROUP_LIMIT_KEY;
+ key.offset = qgroup->qgroupid;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
+ if (ret > 0)
+ ret = -ENOENT;
+
+ if (ret)
+ goto out;
+
+ l = path->nodes[0];
+ slot = path->slots[0];
+ qgroup_limit = btrfs_item_ptr(l, slot, struct btrfs_qgroup_limit_item);
+ btrfs_set_qgroup_limit_flags(l, qgroup_limit, qgroup->lim_flags);
+ btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, qgroup->max_rfer);
+ btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, qgroup->max_excl);
+ btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, qgroup->rsv_rfer);
+ btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, qgroup->rsv_excl);
+
+ btrfs_mark_buffer_dirty(l);
+
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int update_qgroup_info_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_qgroup *qgroup)
+{
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct extent_buffer *l;
+ struct btrfs_qgroup_info_item *qgroup_info;
+ int ret;
+ int slot;
+
+ if (btrfs_test_is_dummy_root(root))
+ return 0;
+
+ key.objectid = 0;
+ key.type = BTRFS_QGROUP_INFO_KEY;
+ key.offset = qgroup->qgroupid;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
+ if (ret > 0)
+ ret = -ENOENT;
+
+ if (ret)
+ goto out;
+
+ l = path->nodes[0];
+ slot = path->slots[0];
+ qgroup_info = btrfs_item_ptr(l, slot, struct btrfs_qgroup_info_item);
+ btrfs_set_qgroup_info_generation(l, qgroup_info, trans->transid);
+ btrfs_set_qgroup_info_rfer(l, qgroup_info, qgroup->rfer);
+ btrfs_set_qgroup_info_rfer_cmpr(l, qgroup_info, qgroup->rfer_cmpr);
+ btrfs_set_qgroup_info_excl(l, qgroup_info, qgroup->excl);
+ btrfs_set_qgroup_info_excl_cmpr(l, qgroup_info, qgroup->excl_cmpr);
+
+ btrfs_mark_buffer_dirty(l);
+
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int update_qgroup_status_item(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info,
+ struct btrfs_root *root)
+{
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct extent_buffer *l;
+ struct btrfs_qgroup_status_item *ptr;
+ int ret;
+ int slot;
+
+ key.objectid = 0;
+ key.type = BTRFS_QGROUP_STATUS_KEY;
+ key.offset = 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
+ if (ret > 0)
+ ret = -ENOENT;
+
+ if (ret)
+ goto out;
+
+ l = path->nodes[0];
+ slot = path->slots[0];
+ ptr = btrfs_item_ptr(l, slot, struct btrfs_qgroup_status_item);
+ btrfs_set_qgroup_status_flags(l, ptr, fs_info->qgroup_flags);
+ btrfs_set_qgroup_status_generation(l, ptr, trans->transid);
+ btrfs_set_qgroup_status_rescan(l, ptr,
+ fs_info->qgroup_rescan_progress.objectid);
+
+ btrfs_mark_buffer_dirty(l);
+
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+/*
+ * called with qgroup_lock held
+ */
+static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct extent_buffer *leaf = NULL;
+ int ret;
+ int nr = 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ path->leave_spinning = 1;
+
+ key.objectid = 0;
+ key.offset = 0;
+ key.type = 0;
+
+ while (1) {
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret < 0)
+ goto out;
+ leaf = path->nodes[0];
+ nr = btrfs_header_nritems(leaf);
+ if (!nr)
+ break;
+ /*
+ * delete the leaf one by one
+ * since the whole tree is going
+ * to be deleted.
+ */
+ path->slots[0] = 0;
+ ret = btrfs_del_items(trans, root, path, 0, nr);
+ if (ret)
+ goto out;
+
+ btrfs_release_path(path);
+ }
+ ret = 0;
+out:
+ root->fs_info->pending_quota_state = 0;
+ btrfs_free_path(path);
+ return ret;
+}
+
+int btrfs_quota_enable(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *quota_root;
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ struct btrfs_path *path = NULL;
+ struct btrfs_qgroup_status_item *ptr;
+ struct extent_buffer *leaf;
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ struct btrfs_qgroup *qgroup = NULL;
+ int ret = 0;
+ int slot;
+
+ mutex_lock(&fs_info->qgroup_ioctl_lock);
+ if (fs_info->quota_root) {
+ fs_info->pending_quota_state = 1;
+ goto out;
+ }
+
+ fs_info->qgroup_ulist = ulist_alloc(GFP_NOFS);
+ if (!fs_info->qgroup_ulist) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ /*
+ * initially create the quota tree
+ */
+ quota_root = btrfs_create_tree(trans, fs_info,
+ BTRFS_QUOTA_TREE_OBJECTID);
+ if (IS_ERR(quota_root)) {
+ ret = PTR_ERR(quota_root);
+ goto out;
+ }
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out_free_root;
+ }
+
+ key.objectid = 0;
+ key.type = BTRFS_QGROUP_STATUS_KEY;
+ key.offset = 0;
+
+ ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
+ sizeof(*ptr));
+ if (ret)
+ goto out_free_path;
+
+ leaf = path->nodes[0];
+ ptr = btrfs_item_ptr(leaf, path->slots[0],
+ struct btrfs_qgroup_status_item);
+ btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
+ btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
+ fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON |
+ BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ btrfs_set_qgroup_status_flags(leaf, ptr, fs_info->qgroup_flags);
+ btrfs_set_qgroup_status_rescan(leaf, ptr, 0);
+
+ btrfs_mark_buffer_dirty(leaf);
+
+ key.objectid = 0;
+ key.type = BTRFS_ROOT_REF_KEY;
+ key.offset = 0;
+
+ btrfs_release_path(path);
+ ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
+ if (ret > 0)
+ goto out_add_root;
+ if (ret < 0)
+ goto out_free_path;
+
+
+ while (1) {
+ slot = path->slots[0];
+ leaf = path->nodes[0];
+ btrfs_item_key_to_cpu(leaf, &found_key, slot);
+
+ if (found_key.type == BTRFS_ROOT_REF_KEY) {
+ ret = add_qgroup_item(trans, quota_root,
+ found_key.offset);
+ if (ret)
+ goto out_free_path;
+
+ qgroup = add_qgroup_rb(fs_info, found_key.offset);
+ if (IS_ERR(qgroup)) {
+ ret = PTR_ERR(qgroup);
+ goto out_free_path;
+ }
+ }
+ ret = btrfs_next_item(tree_root, path);
+ if (ret < 0)
+ goto out_free_path;
+ if (ret)
+ break;
+ }
+
+out_add_root:
+ btrfs_release_path(path);
+ ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
+ if (ret)
+ goto out_free_path;
+
+ qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID);
+ if (IS_ERR(qgroup)) {
+ ret = PTR_ERR(qgroup);
+ goto out_free_path;
+ }
+ spin_lock(&fs_info->qgroup_lock);
+ fs_info->quota_root = quota_root;
+ fs_info->pending_quota_state = 1;
+ spin_unlock(&fs_info->qgroup_lock);
+out_free_path:
+ btrfs_free_path(path);
+out_free_root:
+ if (ret) {
+ free_extent_buffer(quota_root->node);
+ free_extent_buffer(quota_root->commit_root);
+ kfree(quota_root);
+ }
+out:
+ if (ret) {
+ ulist_free(fs_info->qgroup_ulist);
+ fs_info->qgroup_ulist = NULL;
+ }
+ mutex_unlock(&fs_info->qgroup_ioctl_lock);
+ return ret;
+}
+
+int btrfs_quota_disable(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ struct btrfs_root *quota_root;
+ int ret = 0;
+
+ mutex_lock(&fs_info->qgroup_ioctl_lock);
+ if (!fs_info->quota_root)
+ goto out;
+ spin_lock(&fs_info->qgroup_lock);
+ fs_info->quota_enabled = 0;
+ fs_info->pending_quota_state = 0;
+ quota_root = fs_info->quota_root;
+ fs_info->quota_root = NULL;
+ fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
+ spin_unlock(&fs_info->qgroup_lock);
+
+ btrfs_free_qgroup_config(fs_info);
+
+ ret = btrfs_clean_quota_tree(trans, quota_root);
+ if (ret)
+ goto out;
+
+ ret = btrfs_del_root(trans, tree_root, "a_root->root_key);
+ if (ret)
+ goto out;
+
+ list_del("a_root->dirty_list);
+
+ btrfs_tree_lock(quota_root->node);
+ clean_tree_block(trans, tree_root->fs_info, quota_root->node);
+ btrfs_tree_unlock(quota_root->node);
+ btrfs_free_tree_block(trans, quota_root, quota_root->node, 0, 1);
+
+ free_extent_buffer(quota_root->node);
+ free_extent_buffer(quota_root->commit_root);
+ kfree(quota_root);
+out:
+ mutex_unlock(&fs_info->qgroup_ioctl_lock);
+ return ret;
+}
+
+static void qgroup_dirty(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup *qgroup)
+{
+ if (list_empty(&qgroup->dirty))
+ list_add(&qgroup->dirty, &fs_info->dirty_qgroups);
+}
+
+/*
+ * The easy accounting, if we are adding/removing the only ref for an extent
+ * then this qgroup and all of the parent qgroups get their refrence and
+ * exclusive counts adjusted.
+ *
+ * Caller should hold fs_info->qgroup_lock.
+ */
+static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
+ struct ulist *tmp, u64 ref_root,
+ u64 num_bytes, int sign)
+{
+ struct btrfs_qgroup *qgroup;
+ struct btrfs_qgroup_list *glist;
+ struct ulist_node *unode;
+ struct ulist_iterator uiter;
+ int ret = 0;
+
+ qgroup = find_qgroup_rb(fs_info, ref_root);
+ if (!qgroup)
+ goto out;
+
+ qgroup->rfer += sign * num_bytes;
+ qgroup->rfer_cmpr += sign * num_bytes;
+
+ WARN_ON(sign < 0 && qgroup->excl < num_bytes);
+ qgroup->excl += sign * num_bytes;
+ qgroup->excl_cmpr += sign * num_bytes;
+ if (sign > 0)
+ qgroup->reserved -= num_bytes;
+
+ qgroup_dirty(fs_info, qgroup);
+
+ /* Get all of the parent groups that contain this qgroup */
+ list_for_each_entry(glist, &qgroup->groups, next_group) {
+ ret = ulist_add(tmp, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (ret < 0)
+ goto out;
+ }
+
+ /* Iterate all of the parents and adjust their reference counts */
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(tmp, &uiter))) {
+ qgroup = u64_to_ptr(unode->aux);
+ qgroup->rfer += sign * num_bytes;
+ qgroup->rfer_cmpr += sign * num_bytes;
+ WARN_ON(sign < 0 && qgroup->excl < num_bytes);
+ qgroup->excl += sign * num_bytes;
+ if (sign > 0)
+ qgroup->reserved -= num_bytes;
+ qgroup->excl_cmpr += sign * num_bytes;
+ qgroup_dirty(fs_info, qgroup);
+
+ /* Add any parents of the parents */
+ list_for_each_entry(glist, &qgroup->groups, next_group) {
+ ret = ulist_add(tmp, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (ret < 0)
+ goto out;
+ }
+ }
+ ret = 0;
+out:
+ return ret;
+}
+
+
+/*
+ * Quick path for updating qgroup with only excl refs.
+ *
+ * In that case, just update all parent will be enough.
+ * Or we needs to do a full rescan.
+ * Caller should also hold fs_info->qgroup_lock.
+ *
+ * Return 0 for quick update, return >0 for need to full rescan
+ * and mark INCONSISTENT flag.
+ * Return < 0 for other error.
+ */
+static int quick_update_accounting(struct btrfs_fs_info *fs_info,
+ struct ulist *tmp, u64 src, u64 dst,
+ int sign)
+{
+ struct btrfs_qgroup *qgroup;
+ int ret = 1;
+ int err = 0;
+
+ qgroup = find_qgroup_rb(fs_info, src);
+ if (!qgroup)
+ goto out;
+ if (qgroup->excl == qgroup->rfer) {
+ ret = 0;
+ err = __qgroup_excl_accounting(fs_info, tmp, dst,
+ qgroup->excl, sign);
+ if (err < 0) {
+ ret = err;
+ goto out;
+ }
+ }
+out:
+ if (ret)
+ fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ return ret;
+}
+
+int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 src, u64 dst)
+{
+ struct btrfs_root *quota_root;
+ struct btrfs_qgroup *parent;
+ struct btrfs_qgroup *member;
+ struct btrfs_qgroup_list *list;
+ struct ulist *tmp;
+ int ret = 0;
+
+ tmp = ulist_alloc(GFP_NOFS);
+ if (!tmp)
+ return -ENOMEM;
+
+ /* Check the level of src and dst first */
+ if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
+ return -EINVAL;
+
+ mutex_lock(&fs_info->qgroup_ioctl_lock);
+ quota_root = fs_info->quota_root;
+ if (!quota_root) {
+ ret = -EINVAL;
+ goto out;
+ }
+ member = find_qgroup_rb(fs_info, src);
+ parent = find_qgroup_rb(fs_info, dst);
+ if (!member || !parent) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* check if such qgroup relation exist firstly */
+ list_for_each_entry(list, &member->groups, next_group) {
+ if (list->group == parent) {
+ ret = -EEXIST;
+ goto out;
+ }
+ }
+
+ ret = add_qgroup_relation_item(trans, quota_root, src, dst);
+ if (ret)
+ goto out;
+
+ ret = add_qgroup_relation_item(trans, quota_root, dst, src);
+ if (ret) {
+ del_qgroup_relation_item(trans, quota_root, src, dst);
+ goto out;
+ }
+
+ spin_lock(&fs_info->qgroup_lock);
+ ret = add_relation_rb(quota_root->fs_info, src, dst);
+ if (ret < 0) {
+ spin_unlock(&fs_info->qgroup_lock);
+ goto out;
+ }
+ ret = quick_update_accounting(fs_info, tmp, src, dst, 1);
+ spin_unlock(&fs_info->qgroup_lock);
+out:
+ mutex_unlock(&fs_info->qgroup_ioctl_lock);
+ ulist_free(tmp);
+ return ret;
+}
+
+int __del_qgroup_relation(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 src, u64 dst)
+{
+ struct btrfs_root *quota_root;
+ struct btrfs_qgroup *parent;
+ struct btrfs_qgroup *member;
+ struct btrfs_qgroup_list *list;
+ struct ulist *tmp;
+ int ret = 0;
+ int err;
+
+ tmp = ulist_alloc(GFP_NOFS);
+ if (!tmp)
+ return -ENOMEM;
+
+ quota_root = fs_info->quota_root;
+ if (!quota_root) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ member = find_qgroup_rb(fs_info, src);
+ parent = find_qgroup_rb(fs_info, dst);
+ if (!member || !parent) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* check if such qgroup relation exist firstly */
+ list_for_each_entry(list, &member->groups, next_group) {
+ if (list->group == parent)
+ goto exist;
+ }
+ ret = -ENOENT;
+ goto out;
+exist:
+ ret = del_qgroup_relation_item(trans, quota_root, src, dst);
+ err = del_qgroup_relation_item(trans, quota_root, dst, src);
+ if (err && !ret)
+ ret = err;
+
+ spin_lock(&fs_info->qgroup_lock);
+ del_relation_rb(fs_info, src, dst);
+ ret = quick_update_accounting(fs_info, tmp, src, dst, -1);
+ spin_unlock(&fs_info->qgroup_lock);
+out:
+ ulist_free(tmp);
+ return ret;
+}
+
+int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 src, u64 dst)
+{
+ int ret = 0;
+
+ mutex_lock(&fs_info->qgroup_ioctl_lock);
+ ret = __del_qgroup_relation(trans, fs_info, src, dst);
+ mutex_unlock(&fs_info->qgroup_ioctl_lock);
+
+ return ret;
+}
+
+int btrfs_create_qgroup(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 qgroupid)
+{
+ struct btrfs_root *quota_root;
+ struct btrfs_qgroup *qgroup;
+ int ret = 0;
+
+ mutex_lock(&fs_info->qgroup_ioctl_lock);
+ quota_root = fs_info->quota_root;
+ if (!quota_root) {
+ ret = -EINVAL;
+ goto out;
+ }
+ qgroup = find_qgroup_rb(fs_info, qgroupid);
+ if (qgroup) {
+ ret = -EEXIST;
+ goto out;
+ }
+
+ ret = add_qgroup_item(trans, quota_root, qgroupid);
+ if (ret)
+ goto out;
+
+ spin_lock(&fs_info->qgroup_lock);
+ qgroup = add_qgroup_rb(fs_info, qgroupid);
+ spin_unlock(&fs_info->qgroup_lock);
+
+ if (IS_ERR(qgroup))
+ ret = PTR_ERR(qgroup);
+out:
+ mutex_unlock(&fs_info->qgroup_ioctl_lock);
+ return ret;
+}
+
+int btrfs_remove_qgroup(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 qgroupid)
+{
+ struct btrfs_root *quota_root;
+ struct btrfs_qgroup *qgroup;
+ struct btrfs_qgroup_list *list;
+ int ret = 0;
+
+ mutex_lock(&fs_info->qgroup_ioctl_lock);
+ quota_root = fs_info->quota_root;
+ if (!quota_root) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ qgroup = find_qgroup_rb(fs_info, qgroupid);
+ if (!qgroup) {
+ ret = -ENOENT;
+ goto out;
+ } else {
+ /* check if there are no children of this qgroup */
+ if (!list_empty(&qgroup->members)) {
+ ret = -EBUSY;
+ goto out;
+ }
+ }
+ ret = del_qgroup_item(trans, quota_root, qgroupid);
+
+ while (!list_empty(&qgroup->groups)) {
+ list = list_first_entry(&qgroup->groups,
+ struct btrfs_qgroup_list, next_group);
+ ret = __del_qgroup_relation(trans, fs_info,
+ qgroupid,
+ list->group->qgroupid);
+ if (ret)
+ goto out;
+ }
+
+ spin_lock(&fs_info->qgroup_lock);
+ del_qgroup_rb(quota_root->fs_info, qgroupid);
+ spin_unlock(&fs_info->qgroup_lock);
+out:
+ mutex_unlock(&fs_info->qgroup_ioctl_lock);
+ return ret;
+}
+
+int btrfs_limit_qgroup(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 qgroupid,
+ struct btrfs_qgroup_limit *limit)
+{
+ struct btrfs_root *quota_root;
+ struct btrfs_qgroup *qgroup;
+ int ret = 0;
+
+ mutex_lock(&fs_info->qgroup_ioctl_lock);
+ quota_root = fs_info->quota_root;
+ if (!quota_root) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ qgroup = find_qgroup_rb(fs_info, qgroupid);
+ if (!qgroup) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ spin_lock(&fs_info->qgroup_lock);
+ if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_RFER)
+ qgroup->max_rfer = limit->max_rfer;
+ if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL)
+ qgroup->max_excl = limit->max_excl;
+ if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER)
+ qgroup->rsv_rfer = limit->rsv_rfer;
+ if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL)
+ qgroup->rsv_excl = limit->rsv_excl;
+ qgroup->lim_flags |= limit->flags;
+
+ spin_unlock(&fs_info->qgroup_lock);
+
+ ret = update_qgroup_limit_item(trans, quota_root, qgroup);
+ if (ret) {
+ fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ btrfs_info(fs_info, "unable to update quota limit for %llu",
+ qgroupid);
+ }
+
+out:
+ 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)
+{
+ 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;
+ if (oper1->seq < oper2->seq)
+ return -1;
+ if (oper1->seq > oper2->seq)
+ return 1;
+ if (oper1->type < oper2->type)
+ return -1;
+ if (oper1->type > oper2->type)
+ return 1;
+ return 0;
+}
+
+static int insert_qgroup_oper(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup_operation *oper)
+{
+ struct rb_node **p;
+ struct rb_node *parent = NULL;
+ struct btrfs_qgroup_operation *cur;
+ int cmp;
+
+ spin_lock(&fs_info->qgroup_op_lock);
+ p = &fs_info->qgroup_op_tree.rb_node;
+ while (*p) {
+ parent = *p;
+ cur = rb_entry(parent, struct btrfs_qgroup_operation, n);
+ cmp = comp_oper(cur, oper);
+ if (cmp < 0) {
+ p = &(*p)->rb_right;
+ } else if (cmp) {
+ p = &(*p)->rb_left;
+ } else {
+ spin_unlock(&fs_info->qgroup_op_lock);
+ return -EEXIST;
+ }
+ }
+ rb_link_node(&oper->n, parent, p);
+ rb_insert_color(&oper->n, &fs_info->qgroup_op_tree);
+ spin_unlock(&fs_info->qgroup_op_lock);
+ return 0;
+}
+
+/*
+ * Record a quota operation for processing later on.
+ * @trans: the transaction we are adding the delayed op to.
+ * @fs_info: the fs_info for this fs.
+ * @ref_root: the root of the reference we are acting on,
+ * @bytenr: the bytenr we are acting on.
+ * @num_bytes: the number of bytes in the reference.
+ * @type: the type of operation this is.
+ * @mod_seq: do we need to get a sequence number for looking up roots.
+ *
+ * We just add it to our trans qgroup_ref_list and carry on and process these
+ * operations in order at some later point. If the reference root isn't a fs
+ * root then we don't bother with doing anything.
+ *
+ * MUST BE HOLDING THE REF LOCK.
+ */
+int btrfs_qgroup_record_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 ref_root,
+ u64 bytenr, u64 num_bytes,
+ enum btrfs_qgroup_operation_type type, int mod_seq)
+{
+ struct btrfs_qgroup_operation *oper;
+ int ret;
+
+ if (!is_fstree(ref_root) || !fs_info->quota_enabled)
+ return 0;
+
+ oper = kmalloc(sizeof(*oper), GFP_NOFS);
+ if (!oper)
+ return -ENOMEM;
+
+ oper->ref_root = ref_root;
+ oper->bytenr = bytenr;
+ oper->num_bytes = num_bytes;
+ oper->type = type;
+ oper->seq = atomic_inc_return(&fs_info->qgroup_op_seq);
+ INIT_LIST_HEAD(&oper->elem.list);
+ oper->elem.seq = 0;
+
+ trace_btrfs_qgroup_record_ref(oper);
+
+ 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 */
+ ASSERT(0);
+ kfree(oper);
+ return ret;
+ }
+ list_add_tail(&oper->list, &trans->qgroup_ref_list);
+
+ if (mod_seq)
+ btrfs_get_tree_mod_seq(fs_info, &oper->elem);
+
+ return 0;
+}
+
+static int qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup_operation *oper)
+{
+ struct ulist *tmp;
+ int sign = 0;
+ int ret = 0;
+
+ tmp = ulist_alloc(GFP_NOFS);
+ if (!tmp)
+ return -ENOMEM;
+
+ spin_lock(&fs_info->qgroup_lock);
+ if (!fs_info->quota_root)
+ goto out;
+
+ switch (oper->type) {
+ case BTRFS_QGROUP_OPER_ADD_EXCL:
+ sign = 1;
+ break;
+ case BTRFS_QGROUP_OPER_SUB_EXCL:
+ sign = -1;
+ break;
+ default:
+ ASSERT(0);
+ }
+ ret = __qgroup_excl_accounting(fs_info, tmp, oper->ref_root,
+ oper->num_bytes, sign);
+out:
+ spin_unlock(&fs_info->qgroup_lock);
+ ulist_free(tmp);
+ return ret;
+}
+
+/*
+ * Walk all of the roots that pointed to our bytenr and adjust their refcnts as
+ * properly.
+ */
+static int qgroup_calc_old_refcnt(struct btrfs_fs_info *fs_info,
+ u64 root_to_skip, struct ulist *tmp,
+ struct ulist *roots, struct ulist *qgroups,
+ u64 seq, int *old_roots, int rescan)
+{
+ struct ulist_node *unode;
+ struct ulist_iterator uiter;
+ struct ulist_node *tmp_unode;
+ struct ulist_iterator tmp_uiter;
+ struct btrfs_qgroup *qg;
+ int ret;
+
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(roots, &uiter))) {
+ /* We don't count our current root here */
+ if (unode->val == root_to_skip)
+ continue;
+ qg = find_qgroup_rb(fs_info, unode->val);
+ if (!qg)
+ continue;
+ /*
+ * We could have a pending removal of this same ref so we may
+ * not have actually found our ref root when doing
+ * btrfs_find_all_roots, so we need to keep track of how many
+ * old roots we find in case we removed ours and added a
+ * different one at the same time. I don't think this could
+ * happen in practice but that sort of thinking leads to pain
+ * and suffering and to the dark side.
+ */
+ (*old_roots)++;
+
+ ulist_reinit(tmp);
+ ret = ulist_add(qgroups, qg->qgroupid, ptr_to_u64(qg),
+ GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ ret = ulist_add(tmp, qg->qgroupid, ptr_to_u64(qg), GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ ULIST_ITER_INIT(&tmp_uiter);
+ while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
+ struct btrfs_qgroup_list *glist;
+
+ qg = u64_to_ptr(tmp_unode->aux);
+ /*
+ * We use this sequence number to keep from having to
+ * run the whole list and 0 out the refcnt every time.
+ * We basically use sequnce as the known 0 count and
+ * then add 1 everytime we see a qgroup. This is how we
+ * get how many of the roots actually point up to the
+ * upper level qgroups in order to determine exclusive
+ * counts.
+ *
+ * For rescan we want to set old_refcnt to seq so our
+ * exclusive calculations end up correct.
+ */
+ if (rescan)
+ qg->old_refcnt = seq;
+ else if (qg->old_refcnt < seq)
+ qg->old_refcnt = seq + 1;
+ else
+ qg->old_refcnt++;
+
+ if (qg->new_refcnt < seq)
+ qg->new_refcnt = seq + 1;
+ else
+ qg->new_refcnt++;
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ret = ulist_add(qgroups, glist->group->qgroupid,
+ ptr_to_u64(glist->group),
+ GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ ret = ulist_add(tmp, glist->group->qgroupid,
+ ptr_to_u64(glist->group),
+ GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ }
+ }
+ }
+ return 0;
+}
+
+/*
+ * We need to walk forward in our operation tree and account for any roots that
+ * were deleted after we made this operation.
+ */
+static int qgroup_account_deleted_refs(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup_operation *oper,
+ struct ulist *tmp,
+ struct ulist *qgroups, u64 seq,
+ int *old_roots)
+{
+ struct ulist_node *unode;
+ struct ulist_iterator uiter;
+ struct btrfs_qgroup *qg;
+ struct btrfs_qgroup_operation *tmp_oper;
+ struct rb_node *n;
+ int ret;
+
+ ulist_reinit(tmp);
+
+ /*
+ * We only walk forward in the tree since we're only interested in
+ * removals that happened _after_ our operation.
+ */
+ spin_lock(&fs_info->qgroup_op_lock);
+ n = rb_next(&oper->n);
+ spin_unlock(&fs_info->qgroup_op_lock);
+ if (!n)
+ return 0;
+ tmp_oper = rb_entry(n, struct btrfs_qgroup_operation, n);
+ while (tmp_oper->bytenr == oper->bytenr) {
+ /*
+ * If it's not a removal we don't care, additions work out
+ * properly with our refcnt tracking.
+ */
+ if (tmp_oper->type != BTRFS_QGROUP_OPER_SUB_SHARED &&
+ tmp_oper->type != BTRFS_QGROUP_OPER_SUB_EXCL)
+ goto next;
+ qg = find_qgroup_rb(fs_info, tmp_oper->ref_root);
+ if (!qg)
+ goto next;
+ ret = ulist_add(qgroups, qg->qgroupid, ptr_to_u64(qg),
+ GFP_ATOMIC);
+ if (ret) {
+ if (ret < 0)
+ return ret;
+ /*
+ * We only want to increase old_roots if this qgroup is
+ * not already in the list of qgroups. If it is already
+ * there then that means it must have been re-added or
+ * the delete will be discarded because we had an
+ * existing ref that we haven't looked up yet. In this
+ * case we don't want to increase old_roots. So if ret
+ * == 1 then we know that this is the first time we've
+ * seen this qgroup and we can bump the old_roots.
+ */
+ (*old_roots)++;
+ ret = ulist_add(tmp, qg->qgroupid, ptr_to_u64(qg),
+ GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ }
+next:
+ spin_lock(&fs_info->qgroup_op_lock);
+ n = rb_next(&tmp_oper->n);
+ spin_unlock(&fs_info->qgroup_op_lock);
+ if (!n)
+ break;
+ tmp_oper = rb_entry(n, struct btrfs_qgroup_operation, n);
+ }
+
+ /* Ok now process the qgroups we found */
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(tmp, &uiter))) {
+ struct btrfs_qgroup_list *glist;
+
+ qg = u64_to_ptr(unode->aux);
+ if (qg->old_refcnt < seq)
+ qg->old_refcnt = seq + 1;
+ else
+ qg->old_refcnt++;
+ if (qg->new_refcnt < seq)
+ qg->new_refcnt = seq + 1;
+ else
+ qg->new_refcnt++;
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ret = ulist_add(qgroups, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ ret = ulist_add(tmp, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ }
+ }
+ return 0;
+}
+
+/* Add refcnt for the newly added reference. */
+static int qgroup_calc_new_refcnt(struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup_operation *oper,
+ struct btrfs_qgroup *qgroup,
+ struct ulist *tmp, struct ulist *qgroups,
+ u64 seq)
+{
+ struct ulist_node *unode;
+ struct ulist_iterator uiter;
+ struct btrfs_qgroup *qg;
+ int ret;
+
+ ulist_reinit(tmp);
+ ret = ulist_add(qgroups, qgroup->qgroupid, ptr_to_u64(qgroup),
+ GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ ret = ulist_add(tmp, qgroup->qgroupid, ptr_to_u64(qgroup),
+ GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(tmp, &uiter))) {
+ struct btrfs_qgroup_list *glist;
+
+ qg = u64_to_ptr(unode->aux);
+ if (oper->type == BTRFS_QGROUP_OPER_ADD_SHARED) {
+ if (qg->new_refcnt < seq)
+ qg->new_refcnt = seq + 1;
+ else
+ qg->new_refcnt++;
+ } else {
+ if (qg->old_refcnt < seq)
+ qg->old_refcnt = seq + 1;
+ else
+ qg->old_refcnt++;
+ }
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ret = ulist_add(tmp, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ ret = ulist_add(qgroups, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (ret < 0)
+ return ret;
+ }
+ }
+ return 0;
+}
+
+/*
+ * This adjusts the counters for all referenced qgroups if need be.
+ */
+static int qgroup_adjust_counters(struct btrfs_fs_info *fs_info,
+ u64 root_to_skip, u64 num_bytes,
+ struct ulist *qgroups, u64 seq,
+ int old_roots, int new_roots, int rescan)
+{
+ struct ulist_node *unode;
+ struct ulist_iterator uiter;
+ struct btrfs_qgroup *qg;
+ u64 cur_new_count, cur_old_count;
+
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(qgroups, &uiter))) {
+ bool dirty = false;
+
+ qg = u64_to_ptr(unode->aux);
+ /*
+ * Wasn't referenced before but is now, add to the reference
+ * counters.
+ */
+ if (qg->old_refcnt <= seq && qg->new_refcnt > seq) {
+ qg->rfer += num_bytes;
+ qg->rfer_cmpr += num_bytes;
+ dirty = true;
+ }
+
+ /*
+ * Was referenced before but isn't now, subtract from the
+ * reference counters.
+ */
+ if (qg->old_refcnt > seq && qg->new_refcnt <= seq) {
+ qg->rfer -= num_bytes;
+ qg->rfer_cmpr -= num_bytes;
+ dirty = true;
+ }
+
+ if (qg->old_refcnt < seq)
+ cur_old_count = 0;
+ else
+ cur_old_count = qg->old_refcnt - seq;
+ if (qg->new_refcnt < seq)
+ cur_new_count = 0;
+ else
+ cur_new_count = qg->new_refcnt - seq;
+
+ /*
+ * If our refcount was the same as the roots previously but our
+ * new count isn't the same as the number of roots now then we
+ * went from having a exclusive reference on this range to not.
+ */
+ if (old_roots && cur_old_count == old_roots &&
+ (cur_new_count != new_roots || new_roots == 0)) {
+ WARN_ON(cur_new_count != new_roots && new_roots == 0);
+ qg->excl -= num_bytes;
+ qg->excl_cmpr -= num_bytes;
+ dirty = true;
+ }
+
+ /*
+ * If we didn't reference all the roots before but now we do we
+ * have an exclusive reference to this range.
+ */
+ if ((!old_roots || (old_roots && cur_old_count != old_roots))
+ && cur_new_count == new_roots) {
+ qg->excl += num_bytes;
+ qg->excl_cmpr += num_bytes;
+ dirty = true;
+ }
+
+ if (dirty)
+ qgroup_dirty(fs_info, qg);
+ }
+ return 0;
+}
+
+/*
+ * If we removed a data extent and there were other references for that bytenr
+ * then we need to lookup all referenced roots to make sure we still don't
+ * reference this bytenr. If we do then we can just discard this operation.
+ */
+static int check_existing_refs(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;
+ int ret = 0;
+
+ ret = btrfs_find_all_roots(trans, fs_info, oper->bytenr,
+ oper->elem.seq, &roots);
+ if (ret < 0)
+ return ret;
+ ret = 0;
+
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(roots, &uiter))) {
+ if (unode->val == oper->ref_root) {
+ ret = 1;
+ break;
+ }
+ }
+ ulist_free(roots);
+ btrfs_put_tree_mod_seq(fs_info, &oper->elem);
+
+ return ret;
+}
+
+/*
+ * If we share a reference across multiple roots then we may need to adjust
+ * various qgroups referenced and exclusive counters. The basic premise is this
+ *
+ * 1) We have seq to represent a 0 count. Instead of looping through all of the
+ * qgroups and resetting their refcount to 0 we just constantly bump this
+ * sequence number to act as the base reference count. This means that if
+ * anybody is equal to or below this sequence they were never referenced. We
+ * jack this sequence up by the number of roots we found each time in order to
+ * make sure we don't have any overlap.
+ *
+ * 2) We first search all the roots that reference the area _except_ the root
+ * we're acting on currently. This makes up the old_refcnt of all the qgroups
+ * before.
+ *
+ * 3) We walk all of the qgroups referenced by the root we are currently acting
+ * on, and will either adjust old_refcnt in the case of a removal or the
+ * new_refcnt in the case of an addition.
+ *
+ * 4) Finally we walk all the qgroups that are referenced by this range
+ * including the root we are acting on currently. We will adjust the counters
+ * based on the number of roots we had and will have after this operation.
+ *
+ * Take this example as an illustration
+ *
+ * [qgroup 1/0]
+ * / | \
+ * [qg 0/0] [qg 0/1] [qg 0/2]
+ * \ | /
+ * [ extent ]
+ *
+ * Say we are adding a reference that is covered by qg 0/0. The first step
+ * would give a refcnt of 1 to qg 0/1 and 0/2 and a refcnt of 2 to qg 1/0 with
+ * old_roots being 2. Because it is adding new_roots will be 1. We then go
+ * through qg 0/0 which will get the new_refcnt set to 1 and add 1 to qg 1/0's
+ * new_refcnt, bringing it to 3. We then walk through all of the qgroups, we
+ * notice that the old refcnt for qg 0/0 < the new refcnt, so we added a
+ * reference and thus must add the size to the referenced bytes. Everything
+ * else is the same so nothing else changes.
+ */
+static int qgroup_shared_accounting(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup_operation *oper)
+{
+ struct ulist *roots = NULL;
+ struct ulist *qgroups, *tmp;
+ struct btrfs_qgroup *qgroup;
+ struct seq_list elem = SEQ_LIST_INIT(elem);
+ u64 seq;
+ int old_roots = 0;
+ int new_roots = 0;
+ int ret = 0;
+
+ if (oper->elem.seq) {
+ ret = check_existing_refs(trans, fs_info, oper);
+ if (ret < 0)
+ return ret;
+ if (ret)
+ return 0;
+ }
+
+ qgroups = ulist_alloc(GFP_NOFS);
+ if (!qgroups)
+ return -ENOMEM;
+
+ tmp = ulist_alloc(GFP_NOFS);
+ if (!tmp) {
+ ulist_free(qgroups);
+ 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) {
+ ulist_free(qgroups);
+ ulist_free(tmp);
+ return ret;
+ }
+ spin_lock(&fs_info->qgroup_lock);
+ qgroup = find_qgroup_rb(fs_info, oper->ref_root);
+ if (!qgroup)
+ goto out;
+ seq = fs_info->qgroup_seq;
+
+ /*
+ * So roots is the list of all the roots currently pointing at the
+ * bytenr, including the ref we are adding if we are adding, or not if
+ * we are removing a ref. So we pass in the ref_root to skip that root
+ * in our calculations. We set old_refnct and new_refcnt cause who the
+ * hell knows what everything looked like before, and it doesn't matter
+ * except...
+ */
+ ret = qgroup_calc_old_refcnt(fs_info, oper->ref_root, tmp, roots, qgroups,
+ seq, &old_roots, 0);
+ if (ret < 0)
+ goto out;
+
+ /*
+ * Now adjust the refcounts of the qgroups that care about this
+ * reference, either the old_count in the case of removal or new_count
+ * in the case of an addition.
+ */
+ ret = qgroup_calc_new_refcnt(fs_info, oper, qgroup, tmp, qgroups,
+ seq);
+ if (ret < 0)
+ goto out;
+
+ /*
+ * ...in the case of removals. If we had a removal before we got around
+ * to processing this operation then we need to find that guy and count
+ * his references as if they really existed so we don't end up screwing
+ * up the exclusive counts. Then whenever we go to process the delete
+ * everything will be grand and we can account for whatever exclusive
+ * changes need to be made there. We also have to pass in old_roots so
+ * we have an accurate count of the roots as it pertains to this
+ * operations view of the world.
+ */
+ ret = qgroup_account_deleted_refs(fs_info, oper, tmp, qgroups, seq,
+ &old_roots);
+ if (ret < 0)
+ goto out;
+
+ /*
+ * We are adding our root, need to adjust up the number of roots,
+ * otherwise old_roots is the number of roots we want.
+ */
+ if (oper->type == BTRFS_QGROUP_OPER_ADD_SHARED) {
+ new_roots = old_roots + 1;
+ } else {
+ new_roots = old_roots;
+ old_roots++;
+ }
+ fs_info->qgroup_seq += old_roots + 1;
+
+
+ /*
+ * And now the magic happens, bless Arne for having a pretty elegant
+ * solution for this.
+ */
+ qgroup_adjust_counters(fs_info, oper->ref_root, oper->num_bytes,
+ qgroups, seq, old_roots, new_roots, 0);
+out:
+ spin_unlock(&fs_info->qgroup_lock);
+ ulist_free(qgroups);
+ ulist_free(roots);
+ ulist_free(tmp);
+ 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;
+ int err;
+ struct btrfs_qgroup *qg;
+ u64 root_obj = 0;
+ struct seq_list elem = SEQ_LIST_INIT(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)
+ goto out;
+
+ 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) {
+ err = ulist_add(parents, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (err < 0) {
+ ret = err;
+ 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) {
+ err = ulist_add(parents, glist->group->qgroupid,
+ ptr_to_u64(glist->group), GFP_ATOMIC);
+ if (err < 0) {
+ ret = err;
+ 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
+ * then the space is accounted accordingly to the different roots. The
+ * accounting algorithm works in 3 steps documented inline.
+ */
+static int btrfs_qgroup_account(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info,
+ struct btrfs_qgroup_operation *oper)
+{
+ int ret = 0;
+
+ if (!fs_info->quota_enabled)
+ return 0;
+
+ BUG_ON(!fs_info->quota_root);
+
+ mutex_lock(&fs_info->qgroup_rescan_lock);
+ if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
+ if (fs_info->qgroup_rescan_progress.objectid <= oper->bytenr) {
+ mutex_unlock(&fs_info->qgroup_rescan_lock);
+ return 0;
+ }
+ }
+ mutex_unlock(&fs_info->qgroup_rescan_lock);
+
+ ASSERT(is_fstree(oper->ref_root));
+
+ trace_btrfs_qgroup_account(oper);
+
+ switch (oper->type) {
+ case BTRFS_QGROUP_OPER_ADD_EXCL:
+ case BTRFS_QGROUP_OPER_SUB_EXCL:
+ ret = qgroup_excl_accounting(fs_info, oper);
+ break;
+ case BTRFS_QGROUP_OPER_ADD_SHARED:
+ 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);
+ }
+ return ret;
+}
+
+/*
+ * Needs to be called everytime we run delayed refs, even if there is an error
+ * in order to cleanup outstanding operations.
+ */
+int btrfs_delayed_qgroup_accounting(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_qgroup_operation *oper;
+ int ret = 0;
+
+ while (!list_empty(&trans->qgroup_ref_list)) {
+ oper = list_first_entry(&trans->qgroup_ref_list,
+ struct btrfs_qgroup_operation, list);
+ list_del_init(&oper->list);
+ if (!ret || !trans->aborted)
+ ret = btrfs_qgroup_account(trans, fs_info, oper);
+ spin_lock(&fs_info->qgroup_op_lock);
+ rb_erase(&oper->n, &fs_info->qgroup_op_tree);
+ spin_unlock(&fs_info->qgroup_op_lock);
+ btrfs_put_tree_mod_seq(fs_info, &oper->elem);
+ kfree(oper);
+ }
+ return ret;
+}
+
+/*
+ * called from commit_transaction. Writes all changed qgroups to disk.
+ */
+int btrfs_run_qgroups(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_root *quota_root = fs_info->quota_root;
+ int ret = 0;
+ int start_rescan_worker = 0;
+
+ if (!quota_root)
+ goto out;
+
+ if (!fs_info->quota_enabled && fs_info->pending_quota_state)
+ start_rescan_worker = 1;
+
+ fs_info->quota_enabled = fs_info->pending_quota_state;
+
+ spin_lock(&fs_info->qgroup_lock);
+ while (!list_empty(&fs_info->dirty_qgroups)) {
+ struct btrfs_qgroup *qgroup;
+ qgroup = list_first_entry(&fs_info->dirty_qgroups,
+ struct btrfs_qgroup, dirty);
+ list_del_init(&qgroup->dirty);
+ spin_unlock(&fs_info->qgroup_lock);
+ ret = update_qgroup_info_item(trans, quota_root, qgroup);
+ if (ret)
+ fs_info->qgroup_flags |=
+ BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ ret = update_qgroup_limit_item(trans, quota_root, qgroup);
+ if (ret)
+ fs_info->qgroup_flags |=
+ BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ spin_lock(&fs_info->qgroup_lock);
+ }
+ if (fs_info->quota_enabled)
+ fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_ON;
+ else
+ fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_ON;
+ spin_unlock(&fs_info->qgroup_lock);
+
+ ret = update_qgroup_status_item(trans, fs_info, quota_root);
+ if (ret)
+ fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+
+ if (!ret && start_rescan_worker) {
+ ret = qgroup_rescan_init(fs_info, 0, 1);
+ if (!ret) {
+ qgroup_rescan_zero_tracking(fs_info);
+ btrfs_queue_work(fs_info->qgroup_rescan_workers,
+ &fs_info->qgroup_rescan_work);
+ }
+ ret = 0;
+ }
+
+out:
+
+ return ret;
+}
+
+/*
+ * copy the acounting information between qgroups. This is necessary when a
+ * snapshot or a subvolume is created
+ */
+int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 srcid, u64 objectid,
+ struct btrfs_qgroup_inherit *inherit)
+{
+ int ret = 0;
+ int i;
+ u64 *i_qgroups;
+ struct btrfs_root *quota_root = fs_info->quota_root;
+ struct btrfs_qgroup *srcgroup;
+ struct btrfs_qgroup *dstgroup;
+ u32 level_size = 0;
+ u64 nums;
+
+ mutex_lock(&fs_info->qgroup_ioctl_lock);
+ if (!fs_info->quota_enabled)
+ goto out;
+
+ if (!quota_root) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (inherit) {
+ i_qgroups = (u64 *)(inherit + 1);
+ nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
+ 2 * inherit->num_excl_copies;
+ for (i = 0; i < nums; ++i) {
+ srcgroup = find_qgroup_rb(fs_info, *i_qgroups);
+ if (!srcgroup) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if ((srcgroup->qgroupid >> 48) <= (objectid >> 48)) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ++i_qgroups;
+ }
+ }
+
+ /*
+ * create a tracking group for the subvol itself
+ */
+ ret = add_qgroup_item(trans, quota_root, objectid);
+ if (ret)
+ goto out;
+
+ if (srcid) {
+ struct btrfs_root *srcroot;
+ struct btrfs_key srckey;
+
+ srckey.objectid = srcid;
+ srckey.type = BTRFS_ROOT_ITEM_KEY;
+ srckey.offset = (u64)-1;
+ srcroot = btrfs_read_fs_root_no_name(fs_info, &srckey);
+ if (IS_ERR(srcroot)) {
+ ret = PTR_ERR(srcroot);
+ goto out;
+ }
+
+ rcu_read_lock();
+ level_size = srcroot->nodesize;
+ rcu_read_unlock();
+ }
+
+ /*
+ * add qgroup to all inherited groups
+ */
+ if (inherit) {
+ i_qgroups = (u64 *)(inherit + 1);
+ for (i = 0; i < inherit->num_qgroups; ++i) {
+ ret = add_qgroup_relation_item(trans, quota_root,
+ objectid, *i_qgroups);
+ if (ret)
+ goto out;
+ ret = add_qgroup_relation_item(trans, quota_root,
+ *i_qgroups, objectid);
+ if (ret)
+ goto out;
+ ++i_qgroups;
+ }
+ }
+
+
+ spin_lock(&fs_info->qgroup_lock);
+
+ dstgroup = add_qgroup_rb(fs_info, objectid);
+ if (IS_ERR(dstgroup)) {
+ ret = PTR_ERR(dstgroup);
+ goto unlock;
+ }
+
+ if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
+ dstgroup->lim_flags = inherit->lim.flags;
+ dstgroup->max_rfer = inherit->lim.max_rfer;
+ dstgroup->max_excl = inherit->lim.max_excl;
+ dstgroup->rsv_rfer = inherit->lim.rsv_rfer;
+ dstgroup->rsv_excl = inherit->lim.rsv_excl;
+
+ ret = update_qgroup_limit_item(trans, quota_root, dstgroup);
+ if (ret) {
+ fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ btrfs_info(fs_info, "unable to update quota limit for %llu",
+ dstgroup->qgroupid);
+ goto unlock;
+ }
+ }
+
+ if (srcid) {
+ srcgroup = find_qgroup_rb(fs_info, srcid);
+ if (!srcgroup)
+ goto unlock;
+
+ /*
+ * We call inherit after we clone the root in order to make sure
+ * our counts don't go crazy, so at this point the only
+ * difference between the two roots should be the root node.
+ */
+ dstgroup->rfer = srcgroup->rfer;
+ dstgroup->rfer_cmpr = srcgroup->rfer_cmpr;
+ dstgroup->excl = level_size;
+ dstgroup->excl_cmpr = level_size;
+ srcgroup->excl = level_size;
+ srcgroup->excl_cmpr = level_size;
+
+ /* inherit the limit info */
+ dstgroup->lim_flags = srcgroup->lim_flags;
+ dstgroup->max_rfer = srcgroup->max_rfer;
+ dstgroup->max_excl = srcgroup->max_excl;
+ dstgroup->rsv_rfer = srcgroup->rsv_rfer;
+ dstgroup->rsv_excl = srcgroup->rsv_excl;
+
+ qgroup_dirty(fs_info, dstgroup);
+ qgroup_dirty(fs_info, srcgroup);
+ }
+
+ if (!inherit)
+ goto unlock;
+
+ i_qgroups = (u64 *)(inherit + 1);
+ for (i = 0; i < inherit->num_qgroups; ++i) {
+ ret = add_relation_rb(quota_root->fs_info, objectid,
+ *i_qgroups);
+ if (ret)
+ goto unlock;
+ ++i_qgroups;
+ }
+
+ for (i = 0; i < inherit->num_ref_copies; ++i) {
+ struct btrfs_qgroup *src;
+ struct btrfs_qgroup *dst;
+
+ src = find_qgroup_rb(fs_info, i_qgroups[0]);
+ dst = find_qgroup_rb(fs_info, i_qgroups[1]);
+
+ if (!src || !dst) {
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ dst->rfer = src->rfer - level_size;
+ dst->rfer_cmpr = src->rfer_cmpr - level_size;
+ i_qgroups += 2;
+ }
+ for (i = 0; i < inherit->num_excl_copies; ++i) {
+ struct btrfs_qgroup *src;
+ struct btrfs_qgroup *dst;
+
+ src = find_qgroup_rb(fs_info, i_qgroups[0]);
+ dst = find_qgroup_rb(fs_info, i_qgroups[1]);
+
+ if (!src || !dst) {
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ dst->excl = src->excl + level_size;
+ dst->excl_cmpr = src->excl_cmpr + level_size;
+ i_qgroups += 2;
+ }
+
+unlock:
+ spin_unlock(&fs_info->qgroup_lock);
+out:
+ mutex_unlock(&fs_info->qgroup_ioctl_lock);
+ return ret;
+}
+
+int btrfs_qgroup_reserve(struct btrfs_root *root, u64 num_bytes)
+{
+ struct btrfs_root *quota_root;
+ struct btrfs_qgroup *qgroup;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ u64 ref_root = root->root_key.objectid;
+ int ret = 0;
+ struct ulist_node *unode;
+ struct ulist_iterator uiter;
+
+ if (!is_fstree(ref_root))
+ return 0;
+
+ if (num_bytes == 0)
+ return 0;
+
+ spin_lock(&fs_info->qgroup_lock);
+ quota_root = fs_info->quota_root;
+ if (!quota_root)
+ goto out;
+
+ qgroup = find_qgroup_rb(fs_info, ref_root);
+ if (!qgroup)
+ goto out;
+
+ /*
+ * in a first step, we check all affected qgroups if any limits would
+ * be exceeded
+ */
+ ulist_reinit(fs_info->qgroup_ulist);
+ ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
+ (uintptr_t)qgroup, GFP_ATOMIC);
+ if (ret < 0)
+ goto out;
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
+ struct btrfs_qgroup *qg;
+ struct btrfs_qgroup_list *glist;
+
+ qg = u64_to_ptr(unode->aux);
+
+ if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
+ qg->reserved + (s64)qg->rfer + num_bytes >
+ qg->max_rfer) {
+ ret = -EDQUOT;
+ goto out;
+ }
+
+ if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
+ qg->reserved + (s64)qg->excl + num_bytes >
+ qg->max_excl) {
+ ret = -EDQUOT;
+ goto out;
+ }
+
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ret = ulist_add(fs_info->qgroup_ulist,
+ glist->group->qgroupid,
+ (uintptr_t)glist->group, GFP_ATOMIC);
+ if (ret < 0)
+ goto out;
+ }
+ }
+ ret = 0;
+ /*
+ * no limits exceeded, now record the reservation into all qgroups
+ */
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
+ struct btrfs_qgroup *qg;
+
+ qg = u64_to_ptr(unode->aux);
+
+ qg->reserved += num_bytes;
+ }
+
+out:
+ spin_unlock(&fs_info->qgroup_lock);
+ return ret;
+}
+
+void btrfs_qgroup_free(struct btrfs_root *root, u64 num_bytes)
+{
+ struct btrfs_root *quota_root;
+ struct btrfs_qgroup *qgroup;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct ulist_node *unode;
+ struct ulist_iterator uiter;
+ u64 ref_root = root->root_key.objectid;
+ int ret = 0;
+
+ if (!is_fstree(ref_root))
+ return;
+
+ if (num_bytes == 0)
+ return;
+
+ spin_lock(&fs_info->qgroup_lock);
+
+ quota_root = fs_info->quota_root;
+ if (!quota_root)
+ goto out;
+
+ qgroup = find_qgroup_rb(fs_info, ref_root);
+ if (!qgroup)
+ goto out;
+
+ ulist_reinit(fs_info->qgroup_ulist);
+ ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
+ (uintptr_t)qgroup, GFP_ATOMIC);
+ if (ret < 0)
+ goto out;
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
+ struct btrfs_qgroup *qg;
+ struct btrfs_qgroup_list *glist;
+
+ qg = u64_to_ptr(unode->aux);
+
+ qg->reserved -= num_bytes;
+
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ret = ulist_add(fs_info->qgroup_ulist,
+ glist->group->qgroupid,
+ (uintptr_t)glist->group, GFP_ATOMIC);
+ if (ret < 0)
+ goto out;
+ }
+ }
+
+out:
+ spin_unlock(&fs_info->qgroup_lock);
+}
+
+void assert_qgroups_uptodate(struct btrfs_trans_handle *trans)
+{
+ if (list_empty(&trans->qgroup_ref_list) && !trans->delayed_ref_elem.seq)
+ return;
+ btrfs_err(trans->root->fs_info,
+ "qgroups not uptodate in trans handle %p: list is%s empty, "
+ "seq is %#x.%x",
+ trans, list_empty(&trans->qgroup_ref_list) ? "" : " not",
+ (u32)(trans->delayed_ref_elem.seq >> 32),
+ (u32)trans->delayed_ref_elem.seq);
+ BUG();
+}
+
+/*
+ * returns < 0 on error, 0 when more leafs are to be scanned.
+ * returns 1 when done.
+ */
+static int
+qgroup_rescan_leaf(struct btrfs_fs_info *fs_info, struct btrfs_path *path,
+ struct btrfs_trans_handle *trans, struct ulist *qgroups,
+ struct ulist *tmp, struct extent_buffer *scratch_leaf)
+{
+ struct btrfs_key found;
+ struct ulist *roots = NULL;
+ struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
+ u64 num_bytes;
+ u64 seq;
+ int new_roots;
+ int slot;
+ int ret;
+
+ path->leave_spinning = 1;
+ mutex_lock(&fs_info->qgroup_rescan_lock);
+ ret = btrfs_search_slot_for_read(fs_info->extent_root,
+ &fs_info->qgroup_rescan_progress,
+ path, 1, 0);
+
+ pr_debug("current progress key (%llu %u %llu), search_slot ret %d\n",
+ fs_info->qgroup_rescan_progress.objectid,
+ fs_info->qgroup_rescan_progress.type,
+ fs_info->qgroup_rescan_progress.offset, ret);
+
+ if (ret) {
+ /*
+ * The rescan is about to end, we will not be scanning any
+ * further blocks. We cannot unset the RESCAN flag here, because
+ * we want to commit the transaction if everything went well.
+ * To make the live accounting work in this phase, we set our
+ * scan progress pointer such that every real extent objectid
+ * will be smaller.
+ */
+ fs_info->qgroup_rescan_progress.objectid = (u64)-1;
+ btrfs_release_path(path);
+ mutex_unlock(&fs_info->qgroup_rescan_lock);
+ return ret;
+ }
+
+ btrfs_item_key_to_cpu(path->nodes[0], &found,
+ btrfs_header_nritems(path->nodes[0]) - 1);
+ fs_info->qgroup_rescan_progress.objectid = found.objectid + 1;
+
+ btrfs_get_tree_mod_seq(fs_info, &tree_mod_seq_elem);
+ memcpy(scratch_leaf, path->nodes[0], sizeof(*scratch_leaf));
+ slot = path->slots[0];
+ btrfs_release_path(path);
+ mutex_unlock(&fs_info->qgroup_rescan_lock);
+
+ for (; slot < btrfs_header_nritems(scratch_leaf); ++slot) {
+ btrfs_item_key_to_cpu(scratch_leaf, &found, slot);
+ if (found.type != BTRFS_EXTENT_ITEM_KEY &&
+ found.type != BTRFS_METADATA_ITEM_KEY)
+ continue;
+ if (found.type == BTRFS_METADATA_ITEM_KEY)
+ num_bytes = fs_info->extent_root->nodesize;
+ else
+ num_bytes = found.offset;
+
+ ulist_reinit(qgroups);
+ ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0,
+ &roots);
+ if (ret < 0)
+ goto out;
+ spin_lock(&fs_info->qgroup_lock);
+ seq = fs_info->qgroup_seq;
+ fs_info->qgroup_seq += roots->nnodes + 1; /* max refcnt */
+
+ new_roots = 0;
+ ret = qgroup_calc_old_refcnt(fs_info, 0, tmp, roots, qgroups,
+ seq, &new_roots, 1);
+ if (ret < 0) {
+ spin_unlock(&fs_info->qgroup_lock);
+ ulist_free(roots);
+ goto out;
+ }
+
+ ret = qgroup_adjust_counters(fs_info, 0, num_bytes, qgroups,
+ seq, 0, new_roots, 1);
+ if (ret < 0) {
+ spin_unlock(&fs_info->qgroup_lock);
+ ulist_free(roots);
+ goto out;
+ }
+ spin_unlock(&fs_info->qgroup_lock);
+ ulist_free(roots);
+ }
+out:
+ btrfs_put_tree_mod_seq(fs_info, &tree_mod_seq_elem);
+
+ return ret;
+}
+
+static void btrfs_qgroup_rescan_worker(struct btrfs_work *work)
+{
+ struct btrfs_fs_info *fs_info = container_of(work, struct btrfs_fs_info,
+ qgroup_rescan_work);
+ struct btrfs_path *path;
+ struct btrfs_trans_handle *trans = NULL;
+ struct ulist *tmp = NULL, *qgroups = NULL;
+ struct extent_buffer *scratch_leaf = NULL;
+ int err = -ENOMEM;
+ int ret = 0;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ goto out;
+ qgroups = ulist_alloc(GFP_NOFS);
+ if (!qgroups)
+ goto out;
+ tmp = ulist_alloc(GFP_NOFS);
+ if (!tmp)
+ goto out;
+ scratch_leaf = kmalloc(sizeof(*scratch_leaf), GFP_NOFS);
+ if (!scratch_leaf)
+ goto out;
+
+ err = 0;
+ while (!err) {
+ trans = btrfs_start_transaction(fs_info->fs_root, 0);
+ if (IS_ERR(trans)) {
+ err = PTR_ERR(trans);
+ break;
+ }
+ if (!fs_info->quota_enabled) {
+ err = -EINTR;
+ } else {
+ err = qgroup_rescan_leaf(fs_info, path, trans,
+ qgroups, tmp, scratch_leaf);
+ }
+ if (err > 0)
+ btrfs_commit_transaction(trans, fs_info->fs_root);
+ else
+ btrfs_end_transaction(trans, fs_info->fs_root);
+ }
+
+out:
+ kfree(scratch_leaf);
+ ulist_free(qgroups);
+ ulist_free(tmp);
+ btrfs_free_path(path);
+
+ mutex_lock(&fs_info->qgroup_rescan_lock);
+ fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
+
+ if (err > 0 &&
+ fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT) {
+ fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ } else if (err < 0) {
+ fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ }
+ mutex_unlock(&fs_info->qgroup_rescan_lock);
+
+ /*
+ * only update status, since the previous part has alreay updated the
+ * qgroup info.
+ */
+ trans = btrfs_start_transaction(fs_info->quota_root, 1);
+ if (IS_ERR(trans)) {
+ err = PTR_ERR(trans);
+ btrfs_err(fs_info,
+ "fail to start transaction for status update: %d\n",
+ err);
+ goto done;
+ }
+ ret = update_qgroup_status_item(trans, fs_info, fs_info->quota_root);
+ if (ret < 0) {
+ err = ret;
+ btrfs_err(fs_info, "fail to update qgroup status: %d\n", err);
+ }
+ btrfs_end_transaction(trans, fs_info->quota_root);
+
+ if (err >= 0) {
+ btrfs_info(fs_info, "qgroup scan completed%s",
+ err > 0 ? " (inconsistency flag cleared)" : "");
+ } else {
+ btrfs_err(fs_info, "qgroup scan failed with %d", err);
+ }
+
+done:
+ complete_all(&fs_info->qgroup_rescan_completion);
+}
+
+/*
+ * Checks that (a) no rescan is running and (b) quota is enabled. Allocates all
+ * memory required for the rescan context.
+ */
+static int
+qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
+ int init_flags)
+{
+ int ret = 0;
+
+ if (!init_flags &&
+ (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) ||
+ !(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))) {
+ ret = -EINVAL;
+ goto err;
+ }
+
+ mutex_lock(&fs_info->qgroup_rescan_lock);
+ spin_lock(&fs_info->qgroup_lock);
+
+ if (init_flags) {
+ if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
+ ret = -EINPROGRESS;
+ else if (!(fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_ON))
+ ret = -EINVAL;
+
+ if (ret) {
+ spin_unlock(&fs_info->qgroup_lock);
+ mutex_unlock(&fs_info->qgroup_rescan_lock);
+ goto err;
+ }
+ fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
+ }
+
+ memset(&fs_info->qgroup_rescan_progress, 0,
+ sizeof(fs_info->qgroup_rescan_progress));
+ fs_info->qgroup_rescan_progress.objectid = progress_objectid;
+
+ spin_unlock(&fs_info->qgroup_lock);
+ mutex_unlock(&fs_info->qgroup_rescan_lock);
+
+ init_completion(&fs_info->qgroup_rescan_completion);
+
+ memset(&fs_info->qgroup_rescan_work, 0,
+ sizeof(fs_info->qgroup_rescan_work));
+ btrfs_init_work(&fs_info->qgroup_rescan_work,
+ btrfs_qgroup_rescan_helper,
+ btrfs_qgroup_rescan_worker, NULL, NULL);
+
+ if (ret) {
+err:
+ btrfs_info(fs_info, "qgroup_rescan_init failed with %d", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void
+qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info)
+{
+ struct rb_node *n;
+ struct btrfs_qgroup *qgroup;
+
+ spin_lock(&fs_info->qgroup_lock);
+ /* clear all current qgroup tracking information */
+ for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
+ qgroup = rb_entry(n, struct btrfs_qgroup, node);
+ qgroup->rfer = 0;
+ qgroup->rfer_cmpr = 0;
+ qgroup->excl = 0;
+ qgroup->excl_cmpr = 0;
+ }
+ spin_unlock(&fs_info->qgroup_lock);
+}
+
+int
+btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info)
+{
+ int ret = 0;
+ struct btrfs_trans_handle *trans;
+
+ ret = qgroup_rescan_init(fs_info, 0, 1);
+ if (ret)
+ return ret;
+
+ /*
+ * We have set the rescan_progress to 0, which means no more
+ * delayed refs will be accounted by btrfs_qgroup_account_ref.
+ * However, btrfs_qgroup_account_ref may be right after its call
+ * to btrfs_find_all_roots, in which case it would still do the
+ * accounting.
+ * To solve this, we're committing the transaction, which will
+ * ensure we run all delayed refs and only after that, we are
+ * going to clear all tracking information for a clean start.
+ */
+
+ trans = btrfs_join_transaction(fs_info->fs_root);
+ if (IS_ERR(trans)) {
+ fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
+ return PTR_ERR(trans);
+ }
+ ret = btrfs_commit_transaction(trans, fs_info->fs_root);
+ if (ret) {
+ fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN;
+ return ret;
+ }
+
+ qgroup_rescan_zero_tracking(fs_info);
+
+ btrfs_queue_work(fs_info->qgroup_rescan_workers,
+ &fs_info->qgroup_rescan_work);
+
+ return 0;
+}
+
+int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info)
+{
+ int running;
+ int ret = 0;
+
+ mutex_lock(&fs_info->qgroup_rescan_lock);
+ spin_lock(&fs_info->qgroup_lock);
+ running = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN;
+ spin_unlock(&fs_info->qgroup_lock);
+ mutex_unlock(&fs_info->qgroup_rescan_lock);
+
+ if (running)
+ ret = wait_for_completion_interruptible(
+ &fs_info->qgroup_rescan_completion);
+
+ return ret;
+}
+
+/*
+ * this is only called from open_ctree where we're still single threaded, thus
+ * locking is omitted here.
+ */
+void
+btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info)
+{
+ if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN)
+ btrfs_queue_work(fs_info->qgroup_rescan_workers,
+ &fs_info->qgroup_rescan_work);
+}
Code Review / kvmfornfv.git / blobdiff