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-rw-r--r--fs/btrfs/qgroup.c1608
1 files changed, 1608 insertions, 0 deletions
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
new file mode 100644
index 00000000000..a5c85623432
--- /dev/null
+++ b/fs/btrfs/qgroup.c
@@ -0,0 +1,1608 @@
+/*
+ * 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 "ctree.h"
+#include "transaction.h"
+#include "disk-io.h"
+#include "locking.h"
+#include "ulist.h"
+#include "ioctl.h"
+#include "backref.h"
+
+/* TODO XXX FIXME
+ * - subvol delete -> delete when ref goes to 0? delete limits also?
+ * - reorganize keys
+ * - compressed
+ * - sync
+ * - rescan
+ * - 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 tag;
+ u64 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;
+};
+
+/* must be called with qgroup_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;
+}
+
+/* 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);
+ struct btrfs_qgroup_list *list;
+
+ if (!qgroup)
+ return -ENOENT;
+
+ rb_erase(&qgroup->node, &fs_info->qgroup_tree);
+ 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);
+
+ 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;
+}
+
+/*
+ * 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;
+
+ if (!fs_info->quota_enabled)
+ return 0;
+
+ 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) {
+ printk(KERN_ERR
+ "btrfs: old qgroup version, quota disabled\n");
+ goto out;
+ }
+ if (btrfs_qgroup_status_generation(l, ptr) !=
+ fs_info->generation) {
+ flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ printk(KERN_ERR
+ "btrfs: qgroup generation mismatch, "
+ "marked as inconsistent\n");
+ }
+ fs_info->qgroup_flags = btrfs_qgroup_status_flags(l,
+ ptr);
+ /* FIXME read scan element */
+ 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)) {
+ printk(KERN_ERR "btrfs: inconsitent qgroup config\n");
+ 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) {
+ printk(KERN_WARNING
+ "btrfs: orphan qgroup relation 0x%llx->0x%llx\n",
+ (unsigned long long)found_key.objectid,
+ (unsigned long long)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;
+ }
+ btrfs_free_path(path);
+
+ return ret < 0 ? ret : 0;
+}
+
+/*
+ * This is only called from close_ctree() or open_ctree(), both in single-
+ * treaded paths. Clean up the in-memory structures. No locking needed.
+ */
+void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info)
+{
+ struct rb_node *n;
+ struct btrfs_qgroup *qgroup;
+ struct btrfs_qgroup_list *list;
+
+ while ((n = rb_first(&fs_info->qgroup_tree))) {
+ qgroup = rb_entry(n, struct btrfs_qgroup, node);
+ rb_erase(n, &fs_info->qgroup_tree);
+
+ WARN_ON(!list_empty(&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);
+ }
+}
+
+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;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ key.objectid = 0;
+ key.type = BTRFS_QGROUP_INFO_KEY;
+ key.offset = qgroupid;
+
+ ret = btrfs_insert_empty_item(trans, quota_root, path, &key,
+ sizeof(*qgroup_info));
+ if (ret)
+ 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)
+ 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, u64 qgroupid,
+ u64 flags, u64 max_rfer, u64 max_excl,
+ u64 rsv_rfer, u64 rsv_excl)
+{
+ 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 = qgroupid;
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ 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, path->slots[0],
+ struct btrfs_qgroup_limit_item);
+ btrfs_set_qgroup_limit_flags(l, qgroup_limit, flags);
+ btrfs_set_qgroup_limit_max_rfer(l, qgroup_limit, max_rfer);
+ btrfs_set_qgroup_limit_max_excl(l, qgroup_limit, max_excl);
+ btrfs_set_qgroup_limit_rsv_rfer(l, qgroup_limit, rsv_rfer);
+ btrfs_set_qgroup_limit_rsv_excl(l, qgroup_limit, 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;
+
+ key.objectid = 0;
+ key.type = BTRFS_QGROUP_INFO_KEY;
+ key.offset = qgroup->qgroupid;
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ 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, path->slots[0],
+ 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();
+ BUG_ON(!path);
+ 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);
+ /* XXX scan */
+
+ 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;
+ int ret;
+
+ if (!root)
+ return -EINVAL;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ while (1) {
+ key.objectid = 0;
+ key.offset = 0;
+ key.type = 0;
+
+ path->leave_spinning = 1;
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret > 0) {
+ if (path->slots[0] == 0)
+ break;
+ path->slots[0]--;
+ } else if (ret < 0) {
+ break;
+ }
+
+ ret = btrfs_del_item(trans, root, path);
+ 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_path *path = NULL;
+ struct btrfs_qgroup_status_item *ptr;
+ struct extent_buffer *leaf;
+ struct btrfs_key key;
+ int ret = 0;
+
+ spin_lock(&fs_info->qgroup_lock);
+ if (fs_info->quota_root) {
+ fs_info->pending_quota_state = 1;
+ spin_unlock(&fs_info->qgroup_lock);
+ goto out;
+ }
+ spin_unlock(&fs_info->qgroup_lock);
+
+ /*
+ * 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_scan(leaf, ptr, 0);
+
+ btrfs_mark_buffer_dirty(leaf);
+
+ 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:
+ 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;
+
+ 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;
+ btrfs_free_qgroup_config(fs_info);
+ spin_unlock(&fs_info->qgroup_lock);
+
+ if (!quota_root)
+ return -EINVAL;
+
+ ret = btrfs_clean_quota_tree(trans, quota_root);
+ if (ret)
+ goto out;
+
+ ret = btrfs_del_root(trans, tree_root, &quota_root->root_key);
+ if (ret)
+ goto out;
+
+ list_del(&quota_root->dirty_list);
+
+ btrfs_tree_lock(quota_root->node);
+ clean_tree_block(trans, tree_root, 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:
+ return ret;
+}
+
+int btrfs_quota_rescan(struct btrfs_fs_info *fs_info)
+{
+ /* FIXME */
+ return 0;
+}
+
+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;
+ int ret = 0;
+
+ quota_root = fs_info->quota_root;
+ if (!quota_root)
+ return -EINVAL;
+
+ ret = add_qgroup_relation_item(trans, quota_root, src, dst);
+ if (ret)
+ return ret;
+
+ ret = add_qgroup_relation_item(trans, quota_root, dst, src);
+ if (ret) {
+ del_qgroup_relation_item(trans, quota_root, src, dst);
+ return ret;
+ }
+
+ spin_lock(&fs_info->qgroup_lock);
+ ret = add_relation_rb(quota_root->fs_info, src, dst);
+ spin_unlock(&fs_info->qgroup_lock);
+
+ return ret;
+}
+
+int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 src, u64 dst)
+{
+ struct btrfs_root *quota_root;
+ int ret = 0;
+ int err;
+
+ quota_root = fs_info->quota_root;
+ if (!quota_root)
+ return -EINVAL;
+
+ 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);
+
+ spin_unlock(&fs_info->qgroup_lock);
+
+ return ret;
+}
+
+int btrfs_create_qgroup(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 qgroupid, char *name)
+{
+ struct btrfs_root *quota_root;
+ struct btrfs_qgroup *qgroup;
+ int ret = 0;
+
+ quota_root = fs_info->quota_root;
+ if (!quota_root)
+ return -EINVAL;
+
+ ret = add_qgroup_item(trans, quota_root, qgroupid);
+
+ 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);
+
+ 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;
+ int ret = 0;
+
+ quota_root = fs_info->quota_root;
+ if (!quota_root)
+ return -EINVAL;
+
+ /* check if there are no relations to this qgroup */
+ spin_lock(&fs_info->qgroup_lock);
+ qgroup = find_qgroup_rb(fs_info, qgroupid);
+ if (qgroup) {
+ if (!list_empty(&qgroup->groups) || !list_empty(&qgroup->members)) {
+ spin_unlock(&fs_info->qgroup_lock);
+ return -EBUSY;
+ }
+ }
+ spin_unlock(&fs_info->qgroup_lock);
+
+ ret = del_qgroup_item(trans, quota_root, qgroupid);
+
+ spin_lock(&fs_info->qgroup_lock);
+ del_qgroup_rb(quota_root->fs_info, qgroupid);
+ spin_unlock(&fs_info->qgroup_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 = fs_info->quota_root;
+ struct btrfs_qgroup *qgroup;
+ int ret = 0;
+
+ if (!quota_root)
+ return -EINVAL;
+
+ ret = update_qgroup_limit_item(trans, quota_root, qgroupid,
+ limit->flags, limit->max_rfer,
+ limit->max_excl, limit->rsv_rfer,
+ limit->rsv_excl);
+ if (ret) {
+ fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT;
+ printk(KERN_INFO "unable to update quota limit for %llu\n",
+ (unsigned long long)qgroupid);
+ }
+
+ spin_lock(&fs_info->qgroup_lock);
+
+ qgroup = find_qgroup_rb(fs_info, qgroupid);
+ if (!qgroup) {
+ ret = -ENOENT;
+ goto unlock;
+ }
+ qgroup->lim_flags = limit->flags;
+ qgroup->max_rfer = limit->max_rfer;
+ qgroup->max_excl = limit->max_excl;
+ qgroup->rsv_rfer = limit->rsv_rfer;
+ qgroup->rsv_excl = limit->rsv_excl;
+
+unlock:
+ spin_unlock(&fs_info->qgroup_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);
+}
+
+/*
+ * btrfs_qgroup_record_ref is called when the ref is added or deleted. it puts
+ * the modification into a list that's later used by btrfs_end_transaction to
+ * pass the recorded modifications on to btrfs_qgroup_account_ref.
+ */
+int btrfs_qgroup_record_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_delayed_ref_node *node,
+ struct btrfs_delayed_extent_op *extent_op)
+{
+ struct qgroup_update *u;
+
+ BUG_ON(!trans->delayed_ref_elem.seq);
+ u = kmalloc(sizeof(*u), GFP_NOFS);
+ if (!u)
+ return -ENOMEM;
+
+ u->node = node;
+ u->extent_op = extent_op;
+ list_add_tail(&u->list, &trans->qgroup_ref_list);
+
+ return 0;
+}
+
+/*
+ * 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.
+ */
+int btrfs_qgroup_account_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info,
+ struct btrfs_delayed_ref_node *node,
+ struct btrfs_delayed_extent_op *extent_op)
+{
+ struct btrfs_key ins;
+ struct btrfs_root *quota_root;
+ u64 ref_root;
+ struct btrfs_qgroup *qgroup;
+ struct ulist_node *unode;
+ struct ulist *roots = NULL;
+ struct ulist *tmp = NULL;
+ struct ulist_iterator uiter;
+ u64 seq;
+ int ret = 0;
+ int sgn;
+
+ if (!fs_info->quota_enabled)
+ return 0;
+
+ BUG_ON(!fs_info->quota_root);
+
+ ins.objectid = node->bytenr;
+ ins.offset = node->num_bytes;
+ ins.type = BTRFS_EXTENT_ITEM_KEY;
+
+ if (node->type == BTRFS_TREE_BLOCK_REF_KEY ||
+ node->type == BTRFS_SHARED_BLOCK_REF_KEY) {
+ struct btrfs_delayed_tree_ref *ref;
+ ref = btrfs_delayed_node_to_tree_ref(node);
+ ref_root = ref->root;
+ } else if (node->type == BTRFS_EXTENT_DATA_REF_KEY ||
+ node->type == BTRFS_SHARED_DATA_REF_KEY) {
+ struct btrfs_delayed_data_ref *ref;
+ ref = btrfs_delayed_node_to_data_ref(node);
+ ref_root = ref->root;
+ } else {
+ BUG();
+ }
+
+ if (!is_fstree(ref_root)) {
+ /*
+ * non-fs-trees are not being accounted
+ */
+ return 0;
+ }
+
+ switch (node->action) {
+ case BTRFS_ADD_DELAYED_REF:
+ case BTRFS_ADD_DELAYED_EXTENT:
+ sgn = 1;
+ break;
+ case BTRFS_DROP_DELAYED_REF:
+ sgn = -1;
+ break;
+ case BTRFS_UPDATE_DELAYED_HEAD:
+ return 0;
+ default:
+ BUG();
+ }
+
+ /*
+ * the delayed ref sequence number we pass depends on the direction of
+ * the operation. for add operations, we pass (node->seq - 1) to skip
+ * the delayed ref's current sequence number, because we need the state
+ * of the tree before the add operation. for delete operations, we pass
+ * (node->seq) to include the delayed ref's current sequence number,
+ * because we need the state of the tree after the delete operation.
+ */
+ ret = btrfs_find_all_roots(trans, fs_info, node->bytenr,
+ sgn > 0 ? node->seq - 1 : node->seq, &roots);
+ if (ret < 0)
+ goto out;
+
+ spin_lock(&fs_info->qgroup_lock);
+ quota_root = fs_info->quota_root;
+ if (!quota_root)
+ goto unlock;
+
+ qgroup = find_qgroup_rb(fs_info, ref_root);
+ if (!qgroup)
+ goto unlock;
+
+ /*
+ * step 1: for each old ref, visit all nodes once and inc refcnt
+ */
+ tmp = ulist_alloc(GFP_ATOMIC);
+ if (!tmp) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
+ seq = fs_info->qgroup_seq;
+ fs_info->qgroup_seq += roots->nnodes + 1; /* max refcnt */
+
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(roots, &uiter))) {
+ struct ulist_node *tmp_unode;
+ struct ulist_iterator tmp_uiter;
+ struct btrfs_qgroup *qg;
+
+ qg = find_qgroup_rb(fs_info, unode->val);
+ if (!qg)
+ continue;
+
+ ulist_reinit(tmp);
+ /* XXX id not needed */
+ ulist_add(tmp, qg->qgroupid, (u64)(uintptr_t)qg, GFP_ATOMIC);
+ ULIST_ITER_INIT(&tmp_uiter);
+ while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
+ struct btrfs_qgroup_list *glist;
+
+ qg = (struct btrfs_qgroup *)(uintptr_t)tmp_unode->aux;
+ if (qg->refcnt < seq)
+ qg->refcnt = seq + 1;
+ else
+ ++qg->refcnt;
+
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ulist_add(tmp, glist->group->qgroupid,
+ (u64)(uintptr_t)glist->group,
+ GFP_ATOMIC);
+ }
+ }
+ }
+
+ /*
+ * step 2: walk from the new root
+ */
+ ulist_reinit(tmp);
+ ulist_add(tmp, qgroup->qgroupid, (uintptr_t)qgroup, GFP_ATOMIC);
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(tmp, &uiter))) {
+ struct btrfs_qgroup *qg;
+ struct btrfs_qgroup_list *glist;
+
+ qg = (struct btrfs_qgroup *)(uintptr_t)unode->aux;
+ if (qg->refcnt < seq) {
+ /* not visited by step 1 */
+ qg->rfer += sgn * node->num_bytes;
+ qg->rfer_cmpr += sgn * node->num_bytes;
+ if (roots->nnodes == 0) {
+ qg->excl += sgn * node->num_bytes;
+ qg->excl_cmpr += sgn * node->num_bytes;
+ }
+ qgroup_dirty(fs_info, qg);
+ }
+ WARN_ON(qg->tag >= seq);
+ qg->tag = seq;
+
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ulist_add(tmp, glist->group->qgroupid,
+ (uintptr_t)glist->group, GFP_ATOMIC);
+ }
+ }
+
+ /*
+ * step 3: walk again from old refs
+ */
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(roots, &uiter))) {
+ struct btrfs_qgroup *qg;
+ struct ulist_node *tmp_unode;
+ struct ulist_iterator tmp_uiter;
+
+ qg = find_qgroup_rb(fs_info, unode->val);
+ if (!qg)
+ continue;
+
+ ulist_reinit(tmp);
+ ulist_add(tmp, qg->qgroupid, (uintptr_t)qg, GFP_ATOMIC);
+ ULIST_ITER_INIT(&tmp_uiter);
+ while ((tmp_unode = ulist_next(tmp, &tmp_uiter))) {
+ struct btrfs_qgroup_list *glist;
+
+ qg = (struct btrfs_qgroup *)(uintptr_t)tmp_unode->aux;
+ if (qg->tag == seq)
+ continue;
+
+ if (qg->refcnt - seq == roots->nnodes) {
+ qg->excl -= sgn * node->num_bytes;
+ qg->excl_cmpr -= sgn * node->num_bytes;
+ qgroup_dirty(fs_info, qg);
+ }
+
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ulist_add(tmp, glist->group->qgroupid,
+ (uintptr_t)glist->group,
+ GFP_ATOMIC);
+ }
+ }
+ }
+ ret = 0;
+unlock:
+ spin_unlock(&fs_info->qgroup_lock);
+out:
+ ulist_free(roots);
+ ulist_free(tmp);
+
+ 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;
+
+ if (!quota_root)
+ goto out;
+
+ 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;
+ 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;
+
+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;
+
+ if (!fs_info->quota_enabled)
+ return 0;
+
+ if (!quota_root)
+ return -EINVAL;
+
+ /*
+ * create a tracking group for the subvol itself
+ */
+ ret = add_qgroup_item(trans, quota_root, objectid);
+ if (ret)
+ goto out;
+
+ if (inherit && inherit->flags & BTRFS_QGROUP_INHERIT_SET_LIMITS) {
+ ret = update_qgroup_limit_item(trans, quota_root, objectid,
+ inherit->lim.flags,
+ inherit->lim.max_rfer,
+ inherit->lim.max_excl,
+ inherit->lim.rsv_rfer,
+ inherit->lim.rsv_excl);
+ if (ret)
+ goto out;
+ }
+
+ if (srcid) {
+ struct btrfs_root *srcroot;
+ struct btrfs_key srckey;
+ int srcroot_level;
+
+ 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();
+ srcroot_level = btrfs_header_level(srcroot->node);
+ level_size = btrfs_level_size(srcroot, srcroot_level);
+ 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 (srcid) {
+ srcgroup = find_qgroup_rb(fs_info, srcid);
+ if (!srcgroup)
+ goto unlock;
+ dstgroup->rfer = srcgroup->rfer - level_size;
+ dstgroup->rfer_cmpr = srcgroup->rfer_cmpr - level_size;
+ srcgroup->excl = level_size;
+ srcgroup->excl_cmpr = level_size;
+ 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:
+ return ret;
+}
+
+/*
+ * reserve some space for a qgroup and all its parents. The reservation takes
+ * place with start_transaction or dealloc_reserve, similar to ENOSPC
+ * accounting. If not enough space is available, EDQUOT is returned.
+ * We assume that the requested space is new for all qgroups.
+ */
+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 *ulist = NULL;
+ 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 = ulist_alloc(GFP_ATOMIC);
+ if (!ulist) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ulist_add(ulist, qgroup->qgroupid, (uintptr_t)qgroup, GFP_ATOMIC);
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(ulist, &uiter))) {
+ struct btrfs_qgroup *qg;
+ struct btrfs_qgroup_list *glist;
+
+ qg = (struct btrfs_qgroup *)(uintptr_t)unode->aux;
+
+ if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_RFER) &&
+ qg->reserved + qg->rfer + num_bytes >
+ qg->max_rfer)
+ ret = -EDQUOT;
+
+ if ((qg->lim_flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) &&
+ qg->reserved + qg->excl + num_bytes >
+ qg->max_excl)
+ ret = -EDQUOT;
+
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ulist_add(ulist, glist->group->qgroupid,
+ (uintptr_t)glist->group, GFP_ATOMIC);
+ }
+ }
+ if (ret)
+ goto out;
+
+ /*
+ * no limits exceeded, now record the reservation into all qgroups
+ */
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(ulist, &uiter))) {
+ struct btrfs_qgroup *qg;
+
+ qg = (struct btrfs_qgroup *)(uintptr_t)unode->aux;
+
+ qg->reserved += num_bytes;
+ }
+
+out:
+ spin_unlock(&fs_info->qgroup_lock);
+ ulist_free(ulist);
+
+ 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 *ulist = NULL;
+ struct ulist_node *unode;
+ struct ulist_iterator uiter;
+ u64 ref_root = root->root_key.objectid;
+
+ 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 = ulist_alloc(GFP_ATOMIC);
+ if (!ulist) {
+ btrfs_std_error(fs_info, -ENOMEM);
+ goto out;
+ }
+ ulist_add(ulist, qgroup->qgroupid, (uintptr_t)qgroup, GFP_ATOMIC);
+ ULIST_ITER_INIT(&uiter);
+ while ((unode = ulist_next(ulist, &uiter))) {
+ struct btrfs_qgroup *qg;
+ struct btrfs_qgroup_list *glist;
+
+ qg = (struct btrfs_qgroup *)(uintptr_t)unode->aux;
+
+ qg->reserved -= num_bytes;
+
+ list_for_each_entry(glist, &qg->groups, next_group) {
+ ulist_add(ulist, glist->group->qgroupid,
+ (uintptr_t)glist->group, GFP_ATOMIC);
+ }
+ }
+
+out:
+ spin_unlock(&fs_info->qgroup_lock);
+ ulist_free(ulist);
+}
+
+void assert_qgroups_uptodate(struct btrfs_trans_handle *trans)
+{
+ if (list_empty(&trans->qgroup_ref_list) && !trans->delayed_ref_elem.seq)
+ return;
+ printk(KERN_ERR "btrfs: qgroups not uptodate in trans handle %p: list is%s empty, seq is %llu\n",
+ trans, list_empty(&trans->qgroup_ref_list) ? "" : " not",
+ trans->delayed_ref_elem.seq);
+ BUG();
+}