diff options
Diffstat (limited to 'fs/btrfs/qgroup.c')
| -rw-r--r-- | fs/btrfs/qgroup.c | 2966 |
1 files changed, 2966 insertions, 0 deletions
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c new file mode 100644 index 000000000..3d6546581 --- /dev/null +++ b/fs/btrfs/qgroup.c @@ -0,0 +1,2966 @@ +/* + * 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); +} |