linux/fs/btrfs/qgroup.c
Linus Torvalds 089b669506 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "The usual stuff from trivial tree for 4.3 (kerneldoc updates, printk()
  fixes, Documentation and MAINTAINERS updates)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
  MAINTAINERS: update my e-mail address
  mod_devicetable: add space before */
  scsi: a100u2w: trivial typo in printk
  i2c: Fix typo in i2c-bfin-twi.c
  treewide: fix typos in comment blocks
  Doc: fix trivial typo in SubmittingPatches
  proportions: Spelling s/consitent/consistent/
  dm: Spelling s/consitent/consistent/
  aic7xxx: Fix typo in error message
  pcmcia: Fix typo in locking documentation
  scsi/arcmsr: Fix typos in error log
  drm/nouveau/gr: Fix typo in nv10.c
  [SCSI] Fix printk typos in drivers/scsi
  staging: comedi: Grammar s/Enable support a/Enable support for a/
  Btrfs: Spelling s/consitent/consistent/
  README: GTK+ is a acronym
  ASoC: omap: Fix typo in config option description
  mm: tlb.c: Fix error message
  ntfs: super.c: Fix error log
  fix typo in Documentation/SubmittingPatches
  ...
2015-09-01 18:46:42 -07:00

2489 lines
60 KiB
C

/*
* 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
* Refer to qgroup_shared_accouting() for details.
*/
u64 old_refcnt;
u64 new_refcnt;
};
static void btrfs_qgroup_update_old_refcnt(struct btrfs_qgroup *qg, u64 seq,
int mod)
{
if (qg->old_refcnt < seq)
qg->old_refcnt = seq;
qg->old_refcnt += mod;
}
static void btrfs_qgroup_update_new_refcnt(struct btrfs_qgroup *qg, u64 seq,
int mod)
{
if (qg->new_refcnt < seq)
qg->new_refcnt = seq;
qg->new_refcnt += mod;
}
static inline u64 btrfs_qgroup_get_old_refcnt(struct btrfs_qgroup *qg, u64 seq)
{
if (qg->old_refcnt < seq)
return 0;
return qg->old_refcnt - seq;
}
static inline u64 btrfs_qgroup_get_new_refcnt(struct btrfs_qgroup *qg, u64 seq)
{
if (qg->new_refcnt < seq)
return 0;
return qg->new_refcnt - seq;
}
/*
* 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, "inconsistent 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, &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->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;
/* Check the level of src and dst first */
if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
return -EINVAL;
tmp = ulist_alloc(GFP_NOFS);
if (!tmp)
return -ENOMEM;
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;
/* Sometimes we would want to clear the limit on this qgroup.
* To meet this requirement, we treat the -1 as a special value
* which tell kernel to clear the limit on this qgroup.
*/
const u64 CLEAR_VALUE = -1;
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) {
if (limit->max_rfer == CLEAR_VALUE) {
qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_RFER;
qgroup->max_rfer = 0;
} else {
qgroup->max_rfer = limit->max_rfer;
}
}
if (limit->flags & BTRFS_QGROUP_LIMIT_MAX_EXCL) {
if (limit->max_excl == CLEAR_VALUE) {
qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
limit->flags &= ~BTRFS_QGROUP_LIMIT_MAX_EXCL;
qgroup->max_excl = 0;
} else {
qgroup->max_excl = limit->max_excl;
}
}
if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_RFER) {
if (limit->rsv_rfer == CLEAR_VALUE) {
qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_RFER;
qgroup->rsv_rfer = 0;
} else {
qgroup->rsv_rfer = limit->rsv_rfer;
}
}
if (limit->flags & BTRFS_QGROUP_LIMIT_RSV_EXCL) {
if (limit->rsv_excl == CLEAR_VALUE) {
qgroup->lim_flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
limit->flags &= ~BTRFS_QGROUP_LIMIT_RSV_EXCL;
qgroup->rsv_excl = 0;
} else {
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;
}
int btrfs_qgroup_prepare_account_extents(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
struct btrfs_qgroup_extent_record *record;
struct btrfs_delayed_ref_root *delayed_refs;
struct rb_node *node;
u64 qgroup_to_skip;
int ret = 0;
delayed_refs = &trans->transaction->delayed_refs;
qgroup_to_skip = delayed_refs->qgroup_to_skip;
/*
* No need to do lock, since this function will only be called in
* btrfs_commmit_transaction().
*/
node = rb_first(&delayed_refs->dirty_extent_root);
while (node) {
record = rb_entry(node, struct btrfs_qgroup_extent_record,
node);
ret = btrfs_find_all_roots(NULL, fs_info, record->bytenr, 0,
&record->old_roots);
if (ret < 0)
break;
if (qgroup_to_skip)
ulist_del(record->old_roots, qgroup_to_skip, 0);
node = rb_next(node);
}
return ret;
}
struct btrfs_qgroup_extent_record
*btrfs_qgroup_insert_dirty_extent(struct btrfs_delayed_ref_root *delayed_refs,
struct btrfs_qgroup_extent_record *record)
{
struct rb_node **p = &delayed_refs->dirty_extent_root.rb_node;
struct rb_node *parent_node = NULL;
struct btrfs_qgroup_extent_record *entry;
u64 bytenr = record->bytenr;
while (*p) {
parent_node = *p;
entry = rb_entry(parent_node, struct btrfs_qgroup_extent_record,
node);
if (bytenr < entry->bytenr)
p = &(*p)->rb_left;
else if (bytenr > entry->bytenr)
p = &(*p)->rb_right;
else
return entry;
}
rb_link_node(&record->node, parent_node, p);
rb_insert_color(&record->node, &delayed_refs->dirty_extent_root);
return NULL;
}
#define UPDATE_NEW 0
#define UPDATE_OLD 1
/*
* Walk all of the roots that points to the bytenr and adjust their refcnts.
*/
static int qgroup_update_refcnt(struct btrfs_fs_info *fs_info,
struct ulist *roots, struct ulist *tmp,
struct ulist *qgroups, u64 seq, int update_old)
{
struct ulist_node *unode;
struct ulist_iterator uiter;
struct ulist_node *tmp_unode;
struct ulist_iterator tmp_uiter;
struct btrfs_qgroup *qg;
int ret = 0;
if (!roots)
return 0;
ULIST_ITER_INIT(&uiter);
while ((unode = ulist_next(roots, &uiter))) {
qg = find_qgroup_rb(fs_info, unode->val);
if (!qg)
continue;
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);
if (update_old)
btrfs_qgroup_update_old_refcnt(qg, seq, 1);
else
btrfs_qgroup_update_new_refcnt(qg, seq, 1);
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;
}
/*
* Update qgroup rfer/excl counters.
* Rfer update is easy, codes can explain themselves.
*
* Excl update is tricky, the update is split into 2 part.
* Part 1: Possible exclusive <-> sharing detect:
* | A | !A |
* -------------------------------------
* B | * | - |
* -------------------------------------
* !B | + | ** |
* -------------------------------------
*
* Conditions:
* A: cur_old_roots < nr_old_roots (not exclusive before)
* !A: cur_old_roots == nr_old_roots (possible exclusive before)
* B: cur_new_roots < nr_new_roots (not exclusive now)
* !B: cur_new_roots == nr_new_roots (possible exclsuive now)
*
* Results:
* +: Possible sharing -> exclusive -: Possible exclusive -> sharing
* *: Definitely not changed. **: Possible unchanged.
*
* For !A and !B condition, the exception is cur_old/new_roots == 0 case.
*
* To make the logic clear, we first use condition A and B to split
* combination into 4 results.
*
* Then, for result "+" and "-", check old/new_roots == 0 case, as in them
* only on variant maybe 0.
*
* Lastly, check result **, since there are 2 variants maybe 0, split them
* again(2x2).
* But this time we don't need to consider other things, the codes and logic
* is easy to understand now.
*/
static int qgroup_update_counters(struct btrfs_fs_info *fs_info,
struct ulist *qgroups,
u64 nr_old_roots,
u64 nr_new_roots,
u64 num_bytes, u64 seq)
{
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);
cur_old_count = btrfs_qgroup_get_old_refcnt(qg, seq);
cur_new_count = btrfs_qgroup_get_new_refcnt(qg, seq);
/* Rfer update part */
if (cur_old_count == 0 && cur_new_count > 0) {
qg->rfer += num_bytes;
qg->rfer_cmpr += num_bytes;
dirty = true;
}
if (cur_old_count > 0 && cur_new_count == 0) {
qg->rfer -= num_bytes;
qg->rfer_cmpr -= num_bytes;
dirty = true;
}
/* Excl update part */
/* Exclusive/none -> shared case */
if (cur_old_count == nr_old_roots &&
cur_new_count < nr_new_roots) {
/* Exclusive -> shared */
if (cur_old_count != 0) {
qg->excl -= num_bytes;
qg->excl_cmpr -= num_bytes;
dirty = true;
}
}
/* Shared -> exclusive/none case */
if (cur_old_count < nr_old_roots &&
cur_new_count == nr_new_roots) {
/* Shared->exclusive */
if (cur_new_count != 0) {
qg->excl += num_bytes;
qg->excl_cmpr += num_bytes;
dirty = true;
}
}
/* Exclusive/none -> exclusive/none case */
if (cur_old_count == nr_old_roots &&
cur_new_count == nr_new_roots) {
if (cur_old_count == 0) {
/* None -> exclusive/none */
if (cur_new_count != 0) {
/* None -> exclusive */
qg->excl += num_bytes;
qg->excl_cmpr += num_bytes;
dirty = true;
}
/* None -> none, nothing changed */
} else {
/* Exclusive -> exclusive/none */
if (cur_new_count == 0) {
/* Exclusive -> none */
qg->excl -= num_bytes;
qg->excl_cmpr -= num_bytes;
dirty = true;
}
/* Exclusive -> exclusive, nothing changed */
}
}
/* For exclusive extent, free its reserved bytes too */
if (nr_old_roots == 0 && nr_new_roots == 1 &&
cur_new_count == nr_new_roots)
qg->reserved -= num_bytes;
if (dirty)
qgroup_dirty(fs_info, qg);
}
return 0;
}
int
btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info,
u64 bytenr, u64 num_bytes,
struct ulist *old_roots, struct ulist *new_roots)
{
struct ulist *qgroups = NULL;
struct ulist *tmp = NULL;
u64 seq;
u64 nr_new_roots = 0;
u64 nr_old_roots = 0;
int ret = 0;
if (new_roots)
nr_new_roots = new_roots->nnodes;
if (old_roots)
nr_old_roots = old_roots->nnodes;
if (!fs_info->quota_enabled)
goto out_free;
BUG_ON(!fs_info->quota_root);
qgroups = ulist_alloc(GFP_NOFS);
if (!qgroups) {
ret = -ENOMEM;
goto out_free;
}
tmp = ulist_alloc(GFP_NOFS);
if (!tmp) {
ret = -ENOMEM;
goto out_free;
}
mutex_lock(&fs_info->qgroup_rescan_lock);
if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
if (fs_info->qgroup_rescan_progress.objectid <= bytenr) {
mutex_unlock(&fs_info->qgroup_rescan_lock);
ret = 0;
goto out_free;
}
}
mutex_unlock(&fs_info->qgroup_rescan_lock);
spin_lock(&fs_info->qgroup_lock);
seq = fs_info->qgroup_seq;
/* Update old refcnts using old_roots */
ret = qgroup_update_refcnt(fs_info, old_roots, tmp, qgroups, seq,
UPDATE_OLD);
if (ret < 0)
goto out;
/* Update new refcnts using new_roots */
ret = qgroup_update_refcnt(fs_info, new_roots, tmp, qgroups, seq,
UPDATE_NEW);
if (ret < 0)
goto out;
qgroup_update_counters(fs_info, qgroups, nr_old_roots, nr_new_roots,
num_bytes, seq);
/*
* Bump qgroup_seq to avoid seq overlap
*/
fs_info->qgroup_seq += max(nr_old_roots, nr_new_roots) + 1;
out:
spin_unlock(&fs_info->qgroup_lock);
out_free:
ulist_free(tmp);
ulist_free(qgroups);
ulist_free(old_roots);
ulist_free(new_roots);
return ret;
}
int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
struct btrfs_qgroup_extent_record *record;
struct btrfs_delayed_ref_root *delayed_refs;
struct ulist *new_roots = NULL;
struct rb_node *node;
u64 qgroup_to_skip;
int ret = 0;
delayed_refs = &trans->transaction->delayed_refs;
qgroup_to_skip = delayed_refs->qgroup_to_skip;
while ((node = rb_first(&delayed_refs->dirty_extent_root))) {
record = rb_entry(node, struct btrfs_qgroup_extent_record,
node);
if (!ret) {
/*
* Use (u64)-1 as time_seq to do special search, which
* doesn't lock tree or delayed_refs and search current
* root. It's safe inside commit_transaction().
*/
ret = btrfs_find_all_roots(trans, fs_info,
record->bytenr, (u64)-1, &new_roots);
if (ret < 0)
goto cleanup;
if (qgroup_to_skip)
ulist_del(new_roots, qgroup_to_skip, 0);
ret = btrfs_qgroup_account_extent(trans, fs_info,
record->bytenr, record->num_bytes,
record->old_roots, new_roots);
record->old_roots = NULL;
new_roots = NULL;
}
cleanup:
ulist_free(record->old_roots);
ulist_free(new_roots);
new_roots = NULL;
rb_erase(node, &delayed_refs->dirty_extent_root);
kfree(record);
}
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 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;
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;
ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0,
&roots);
if (ret < 0)
goto out;
/* For rescan, just pass old_roots as NULL */
ret = btrfs_qgroup_account_extent(trans, fs_info,
found.objectid, num_bytes, NULL, roots);
if (ret < 0)
goto out;
}
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 extent_buffer *scratch_leaf = NULL;
int err = -ENOMEM;
int ret = 0;
path = btrfs_alloc_path();
if (!path)
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,
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);
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);
}