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quota.c
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/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
/*
* Quota change tags are associated with each transaction that allocates or
* deallocates space. Those changes are accumulated locally to each node (in a
* per-node file) and then are periodically synced to the quota file. This
* avoids the bottleneck of constantly touching the quota file, but introduces
* fuzziness in the current usage value of IDs that are being used on different
* nodes in the cluster simultaneously. So, it is possible for a user on
* multiple nodes to overrun their quota, but that overrun is controlable.
* Since quota tags are part of transactions, there is no need for a quota check
* program to be run on node crashes or anything like that.
*
* There are couple of knobs that let the administrator manage the quota
* fuzziness. "quota_quantum" sets the maximum time a quota change can be
* sitting on one node before being synced to the quota file. (The default is
* 60 seconds.) Another knob, "quota_scale" controls how quickly the frequency
* of quota file syncs increases as the user moves closer to their limit. The
* more frequent the syncs, the more accurate the quota enforcement, but that
* means that there is more contention between the nodes for the quota file.
* The default value is one. This sets the maximum theoretical quota overrun
* (with infinite node with infinite bandwidth) to twice the user's limit. (In
* practice, the maximum overrun you see should be much less.) A "quota_scale"
* number greater than one makes quota syncs more frequent and reduces the
* maximum overrun. Numbers less than one (but greater than zero) make quota
* syncs less frequent.
*
* GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
* the quota file, so it is not being constantly read.
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/sort.h>
#include <linux/fs.h>
#include <linux/bio.h>
#include <linux/gfs2_ondisk.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <linux/quota.h>
#include <linux/dqblk_xfs.h>
#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "glock.h"
#include "glops.h"
#include "log.h"
#include "meta_io.h"
#include "quota.h"
#include "rgrp.h"
#include "super.h"
#include "trans.h"
#include "inode.h"
#include "util.h"
#define QUOTA_USER 1
#define QUOTA_GROUP 0
struct gfs2_quota_change_host {
u64 qc_change;
u32 qc_flags; /* GFS2_QCF_... */
u32 qc_id;
};
static LIST_HEAD(qd_lru_list);
static atomic_t qd_lru_count = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(qd_lru_lock);
int gfs2_shrink_qd_memory(int nr, gfp_t gfp_mask)
{
struct gfs2_quota_data *qd;
struct gfs2_sbd *sdp;
if (nr == 0)
goto out;
if (!(gfp_mask & __GFP_FS))
return -1;
spin_lock(&qd_lru_lock);
while (nr && !list_empty(&qd_lru_list)) {
qd = list_entry(qd_lru_list.next,
struct gfs2_quota_data, qd_reclaim);
sdp = qd->qd_gl->gl_sbd;
/* Free from the filesystem-specific list */
list_del(&qd->qd_list);
gfs2_assert_warn(sdp, !qd->qd_change);
gfs2_assert_warn(sdp, !qd->qd_slot_count);
gfs2_assert_warn(sdp, !qd->qd_bh_count);
gfs2_glock_put(qd->qd_gl);
atomic_dec(&sdp->sd_quota_count);
/* Delete it from the common reclaim list */
list_del_init(&qd->qd_reclaim);
atomic_dec(&qd_lru_count);
spin_unlock(&qd_lru_lock);
kmem_cache_free(gfs2_quotad_cachep, qd);
spin_lock(&qd_lru_lock);
nr--;
}
spin_unlock(&qd_lru_lock);
out:
return (atomic_read(&qd_lru_count) * sysctl_vfs_cache_pressure) / 100;
}
static u64 qd2offset(struct gfs2_quota_data *qd)
{
u64 offset;
offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
offset *= sizeof(struct gfs2_quota);
return offset;
}
static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
struct gfs2_quota_data **qdp)
{
struct gfs2_quota_data *qd;
int error;
qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
if (!qd)
return -ENOMEM;
atomic_set(&qd->qd_count, 1);
qd->qd_id = id;
if (user)
set_bit(QDF_USER, &qd->qd_flags);
qd->qd_slot = -1;
INIT_LIST_HEAD(&qd->qd_reclaim);
error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
&gfs2_quota_glops, CREATE, &qd->qd_gl);
if (error)
goto fail;
*qdp = qd;
return 0;
fail:
kmem_cache_free(gfs2_quotad_cachep, qd);
return error;
}
static int qd_get(struct gfs2_sbd *sdp, int user, u32 id,
struct gfs2_quota_data **qdp)
{
struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
int error, found;
*qdp = NULL;
for (;;) {
found = 0;
spin_lock(&qd_lru_lock);
list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
if (qd->qd_id == id &&
!test_bit(QDF_USER, &qd->qd_flags) == !user) {
if (!atomic_read(&qd->qd_count) &&
!list_empty(&qd->qd_reclaim)) {
/* Remove it from reclaim list */
list_del_init(&qd->qd_reclaim);
atomic_dec(&qd_lru_count);
}
atomic_inc(&qd->qd_count);
found = 1;
break;
}
}
if (!found)
qd = NULL;
if (!qd && new_qd) {
qd = new_qd;
list_add(&qd->qd_list, &sdp->sd_quota_list);
atomic_inc(&sdp->sd_quota_count);
new_qd = NULL;
}
spin_unlock(&qd_lru_lock);
if (qd) {
if (new_qd) {
gfs2_glock_put(new_qd->qd_gl);
kmem_cache_free(gfs2_quotad_cachep, new_qd);
}
*qdp = qd;
return 0;
}
error = qd_alloc(sdp, user, id, &new_qd);
if (error)
return error;
}
}
static void qd_hold(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
gfs2_assert(sdp, atomic_read(&qd->qd_count));
atomic_inc(&qd->qd_count);
}
static void qd_put(struct gfs2_quota_data *qd)
{
if (atomic_dec_and_lock(&qd->qd_count, &qd_lru_lock)) {
/* Add to the reclaim list */
list_add_tail(&qd->qd_reclaim, &qd_lru_list);
atomic_inc(&qd_lru_count);
spin_unlock(&qd_lru_lock);
}
}
static int slot_get(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
unsigned int c, o = 0, b;
unsigned char byte = 0;
spin_lock(&qd_lru_lock);
if (qd->qd_slot_count++) {
spin_unlock(&qd_lru_lock);
return 0;
}
for (c = 0; c < sdp->sd_quota_chunks; c++)
for (o = 0; o < PAGE_SIZE; o++) {
byte = sdp->sd_quota_bitmap[c][o];
if (byte != 0xFF)
goto found;
}
goto fail;
found:
for (b = 0; b < 8; b++)
if (!(byte & (1 << b)))
break;
qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
if (qd->qd_slot >= sdp->sd_quota_slots)
goto fail;
sdp->sd_quota_bitmap[c][o] |= 1 << b;
spin_unlock(&qd_lru_lock);
return 0;
fail:
qd->qd_slot_count--;
spin_unlock(&qd_lru_lock);
return -ENOSPC;
}
static void slot_hold(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
spin_lock(&qd_lru_lock);
gfs2_assert(sdp, qd->qd_slot_count);
qd->qd_slot_count++;
spin_unlock(&qd_lru_lock);
}
static void slot_put(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
spin_lock(&qd_lru_lock);
gfs2_assert(sdp, qd->qd_slot_count);
if (!--qd->qd_slot_count) {
gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
qd->qd_slot = -1;
}
spin_unlock(&qd_lru_lock);
}
static int bh_get(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
unsigned int block, offset;
struct buffer_head *bh;
int error;
struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
mutex_lock(&sdp->sd_quota_mutex);
if (qd->qd_bh_count++) {
mutex_unlock(&sdp->sd_quota_mutex);
return 0;
}
block = qd->qd_slot / sdp->sd_qc_per_block;
offset = qd->qd_slot % sdp->sd_qc_per_block;
bh_map.b_size = 1 << ip->i_inode.i_blkbits;
error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
if (error)
goto fail;
error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
if (error)
goto fail;
error = -EIO;
if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
goto fail_brelse;
qd->qd_bh = bh;
qd->qd_bh_qc = (struct gfs2_quota_change *)
(bh->b_data + sizeof(struct gfs2_meta_header) +
offset * sizeof(struct gfs2_quota_change));
mutex_unlock(&sdp->sd_quota_mutex);
return 0;
fail_brelse:
brelse(bh);
fail:
qd->qd_bh_count--;
mutex_unlock(&sdp->sd_quota_mutex);
return error;
}
static void bh_put(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
mutex_lock(&sdp->sd_quota_mutex);
gfs2_assert(sdp, qd->qd_bh_count);
if (!--qd->qd_bh_count) {
brelse(qd->qd_bh);
qd->qd_bh = NULL;
qd->qd_bh_qc = NULL;
}
mutex_unlock(&sdp->sd_quota_mutex);
}
static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
{
struct gfs2_quota_data *qd = NULL;
int error;
int found = 0;
*qdp = NULL;
if (sdp->sd_vfs->s_flags & MS_RDONLY)
return 0;
spin_lock(&qd_lru_lock);
list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
!test_bit(QDF_CHANGE, &qd->qd_flags) ||
qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
continue;
list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
set_bit(QDF_LOCKED, &qd->qd_flags);
gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
atomic_inc(&qd->qd_count);
qd->qd_change_sync = qd->qd_change;
gfs2_assert_warn(sdp, qd->qd_slot_count);
qd->qd_slot_count++;
found = 1;
break;
}
if (!found)
qd = NULL;
spin_unlock(&qd_lru_lock);
if (qd) {
gfs2_assert_warn(sdp, qd->qd_change_sync);
error = bh_get(qd);
if (error) {
clear_bit(QDF_LOCKED, &qd->qd_flags);
slot_put(qd);
qd_put(qd);
return error;
}
}
*qdp = qd;
return 0;
}
static int qd_trylock(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
if (sdp->sd_vfs->s_flags & MS_RDONLY)
return 0;
spin_lock(&qd_lru_lock);
if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
!test_bit(QDF_CHANGE, &qd->qd_flags)) {
spin_unlock(&qd_lru_lock);
return 0;
}
list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
set_bit(QDF_LOCKED, &qd->qd_flags);
gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
atomic_inc(&qd->qd_count);
qd->qd_change_sync = qd->qd_change;
gfs2_assert_warn(sdp, qd->qd_slot_count);
qd->qd_slot_count++;
spin_unlock(&qd_lru_lock);
gfs2_assert_warn(sdp, qd->qd_change_sync);
if (bh_get(qd)) {
clear_bit(QDF_LOCKED, &qd->qd_flags);
slot_put(qd);
qd_put(qd);
return 0;
}
return 1;
}
static void qd_unlock(struct gfs2_quota_data *qd)
{
gfs2_assert_warn(qd->qd_gl->gl_sbd,
test_bit(QDF_LOCKED, &qd->qd_flags));
clear_bit(QDF_LOCKED, &qd->qd_flags);
bh_put(qd);
slot_put(qd);
qd_put(qd);
}
static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id,
struct gfs2_quota_data **qdp)
{
int error;
error = qd_get(sdp, user, id, qdp);
if (error)
return error;
error = slot_get(*qdp);
if (error)
goto fail;
error = bh_get(*qdp);
if (error)
goto fail_slot;
return 0;
fail_slot:
slot_put(*qdp);
fail:
qd_put(*qdp);
return error;
}
static void qdsb_put(struct gfs2_quota_data *qd)
{
bh_put(qd);
slot_put(qd);
qd_put(qd);
}
int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_alloc *al = ip->i_alloc;
struct gfs2_quota_data **qd = al->al_qd;
int error;
if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
return -EIO;
if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
return 0;
error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, qd);
if (error)
goto out;
al->al_qd_num++;
qd++;
error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, qd);
if (error)
goto out;
al->al_qd_num++;
qd++;
if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
error = qdsb_get(sdp, QUOTA_USER, uid, qd);
if (error)
goto out;
al->al_qd_num++;
qd++;
}
if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
error = qdsb_get(sdp, QUOTA_GROUP, gid, qd);
if (error)
goto out;
al->al_qd_num++;
qd++;
}
out:
if (error)
gfs2_quota_unhold(ip);
return error;
}
void gfs2_quota_unhold(struct gfs2_inode *ip)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_alloc *al = ip->i_alloc;
unsigned int x;
gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
for (x = 0; x < al->al_qd_num; x++) {
qdsb_put(al->al_qd[x]);
al->al_qd[x] = NULL;
}
al->al_qd_num = 0;
}
static int sort_qd(const void *a, const void *b)
{
const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
!test_bit(QDF_USER, &qd_b->qd_flags)) {
if (test_bit(QDF_USER, &qd_a->qd_flags))
return -1;
else
return 1;
}
if (qd_a->qd_id < qd_b->qd_id)
return -1;
if (qd_a->qd_id > qd_b->qd_id)
return 1;
return 0;
}
static void do_qc(struct gfs2_quota_data *qd, s64 change)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
struct gfs2_quota_change *qc = qd->qd_bh_qc;
s64 x;
mutex_lock(&sdp->sd_quota_mutex);
gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
qc->qc_change = 0;
qc->qc_flags = 0;
if (test_bit(QDF_USER, &qd->qd_flags))
qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
qc->qc_id = cpu_to_be32(qd->qd_id);
}
x = be64_to_cpu(qc->qc_change) + change;
qc->qc_change = cpu_to_be64(x);
spin_lock(&qd_lru_lock);
qd->qd_change = x;
spin_unlock(&qd_lru_lock);
if (!x) {
gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
clear_bit(QDF_CHANGE, &qd->qd_flags);
qc->qc_flags = 0;
qc->qc_id = 0;
slot_put(qd);
qd_put(qd);
} else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
qd_hold(qd);
slot_hold(qd);
}
mutex_unlock(&sdp->sd_quota_mutex);
}
/**
* gfs2_adjust_quota - adjust record of current block usage
* @ip: The quota inode
* @loc: Offset of the entry in the quota file
* @change: The amount of usage change to record
* @qd: The quota data
* @fdq: The updated limits to record
*
* This function was mostly borrowed from gfs2_block_truncate_page which was
* in turn mostly borrowed from ext3
*
* Returns: 0 or -ve on error
*/
static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
s64 change, struct gfs2_quota_data *qd,
struct fs_disk_quota *fdq)
{
struct inode *inode = &ip->i_inode;
struct address_space *mapping = inode->i_mapping;
unsigned long index = loc >> PAGE_CACHE_SHIFT;
unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
unsigned blocksize, iblock, pos;
struct buffer_head *bh, *dibh;
struct page *page;
void *kaddr;
struct gfs2_quota *qp;
s64 value;
int err = -EIO;
u64 size;
if (gfs2_is_stuffed(ip))
gfs2_unstuff_dinode(ip, NULL);
page = grab_cache_page(mapping, index);
if (!page)
return -ENOMEM;
blocksize = inode->i_sb->s_blocksize;
iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
if (!page_has_buffers(page))
create_empty_buffers(page, blocksize, 0);
bh = page_buffers(page);
pos = blocksize;
while (offset >= pos) {
bh = bh->b_this_page;
iblock++;
pos += blocksize;
}
if (!buffer_mapped(bh)) {
gfs2_block_map(inode, iblock, bh, 1);
if (!buffer_mapped(bh))
goto unlock;
}
if (PageUptodate(page))
set_buffer_uptodate(bh);
if (!buffer_uptodate(bh)) {
ll_rw_block(READ_META, 1, &bh);
wait_on_buffer(bh);
if (!buffer_uptodate(bh))
goto unlock;
}
gfs2_trans_add_bh(ip->i_gl, bh, 0);
kaddr = kmap_atomic(page, KM_USER0);
qp = kaddr + offset;
value = (s64)be64_to_cpu(qp->qu_value) + change;
qp->qu_value = cpu_to_be64(value);
qd->qd_qb.qb_value = qp->qu_value;
if (fdq) {
if (fdq->d_fieldmask & FS_DQ_BSOFT) {
qp->qu_warn = cpu_to_be64(fdq->d_blk_softlimit);
qd->qd_qb.qb_warn = qp->qu_warn;
}
if (fdq->d_fieldmask & FS_DQ_BHARD) {
qp->qu_limit = cpu_to_be64(fdq->d_blk_hardlimit);
qd->qd_qb.qb_limit = qp->qu_limit;
}
}
flush_dcache_page(page);
kunmap_atomic(kaddr, KM_USER0);
err = gfs2_meta_inode_buffer(ip, &dibh);
if (err)
goto unlock;
size = loc + sizeof(struct gfs2_quota);
if (size > inode->i_size) {
ip->i_disksize = size;
i_size_write(inode, size);
}
inode->i_mtime = inode->i_atime = CURRENT_TIME;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
brelse(dibh);
mark_inode_dirty(inode);
unlock:
unlock_page(page);
page_cache_release(page);
return err;
}
static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
{
struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
unsigned int data_blocks, ind_blocks;
struct gfs2_holder *ghs, i_gh;
unsigned int qx, x;
struct gfs2_quota_data *qd;
loff_t offset;
unsigned int nalloc = 0, blocks;
struct gfs2_alloc *al = NULL;
int error;
gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
&data_blocks, &ind_blocks);
ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
if (!ghs)
return -ENOMEM;
sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
mutex_lock_nested(&ip->i_inode.i_mutex, I_MUTEX_QUOTA);
for (qx = 0; qx < num_qd; qx++) {
error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
GL_NOCACHE, &ghs[qx]);
if (error)
goto out;
}
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
if (error)
goto out;
for (x = 0; x < num_qd; x++) {
int alloc_required;
offset = qd2offset(qda[x]);
error = gfs2_write_alloc_required(ip, offset,
sizeof(struct gfs2_quota),
&alloc_required);
if (error)
goto out_gunlock;
if (alloc_required)
nalloc++;
}
al = gfs2_alloc_get(ip);
if (!al) {
error = -ENOMEM;
goto out_gunlock;
}
/*
* 1 blk for unstuffing inode if stuffed. We add this extra
* block to the reservation unconditionally. If the inode
* doesn't need unstuffing, the block will be released to the
* rgrp since it won't be allocated during the transaction
*/
al->al_requested = 1;
/* +1 in the end for block requested above for unstuffing */
blocks = num_qd * data_blocks + RES_DINODE + num_qd + 1;
if (nalloc)
al->al_requested += nalloc * (data_blocks + ind_blocks);
error = gfs2_inplace_reserve(ip);
if (error)
goto out_alloc;
if (nalloc)
blocks += al->al_rgd->rd_length + nalloc * ind_blocks + RES_STATFS;
error = gfs2_trans_begin(sdp, blocks, 0);
if (error)
goto out_ipres;
for (x = 0; x < num_qd; x++) {
qd = qda[x];
offset = qd2offset(qd);
error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
if (error)
goto out_end_trans;
do_qc(qd, -qd->qd_change_sync);
}
error = 0;
out_end_trans:
gfs2_trans_end(sdp);
out_ipres:
gfs2_inplace_release(ip);
out_alloc:
gfs2_alloc_put(ip);
out_gunlock:
gfs2_glock_dq_uninit(&i_gh);
out:
while (qx--)
gfs2_glock_dq_uninit(&ghs[qx]);
mutex_unlock(&ip->i_inode.i_mutex);
kfree(ghs);
gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
return error;
}
static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
{
struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
struct gfs2_quota q;
struct gfs2_quota_lvb *qlvb;
loff_t pos;
int error;
memset(&q, 0, sizeof(struct gfs2_quota));
pos = qd2offset(qd);
error = gfs2_internal_read(ip, NULL, (char *)&q, &pos, sizeof(q));
if (error < 0)
return error;
qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
qlvb->__pad = 0;
qlvb->qb_limit = q.qu_limit;
qlvb->qb_warn = q.qu_warn;
qlvb->qb_value = q.qu_value;
qd->qd_qb = *qlvb;
return 0;
}
static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
struct gfs2_holder *q_gh)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
struct gfs2_holder i_gh;
int error;
restart:
error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
if (error)
return error;
qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
gfs2_glock_dq_uninit(q_gh);
error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
GL_NOCACHE, q_gh);
if (error)
return error;
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
if (error)
goto fail;
error = update_qd(sdp, qd);
if (error)
goto fail_gunlock;
gfs2_glock_dq_uninit(&i_gh);
gfs2_glock_dq_uninit(q_gh);
force_refresh = 0;
goto restart;
}
return 0;
fail_gunlock:
gfs2_glock_dq_uninit(&i_gh);
fail:
gfs2_glock_dq_uninit(q_gh);
return error;
}
int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_alloc *al = ip->i_alloc;
unsigned int x;
int error = 0;
gfs2_quota_hold(ip, uid, gid);
if (capable(CAP_SYS_RESOURCE) ||
sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
return 0;
sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
sort_qd, NULL);
for (x = 0; x < al->al_qd_num; x++) {
error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
if (error)
break;
}
if (!error)
set_bit(GIF_QD_LOCKED, &ip->i_flags);
else {
while (x--)
gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
gfs2_quota_unhold(ip);
}
return error;
}
static int need_sync(struct gfs2_quota_data *qd)
{
struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
struct gfs2_tune *gt = &sdp->sd_tune;
s64 value;
unsigned int num, den;
int do_sync = 1;
if (!qd->qd_qb.qb_limit)
return 0;
spin_lock(&qd_lru_lock);
value = qd->qd_change;
spin_unlock(&qd_lru_lock);
spin_lock(>->gt_spin);
num = gt->gt_quota_scale_num;
den = gt->gt_quota_scale_den;
spin_unlock(>->gt_spin);
if (value < 0)
do_sync = 0;
else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
(s64)be64_to_cpu(qd->qd_qb.qb_limit))
do_sync = 0;
else {
value *= gfs2_jindex_size(sdp) * num;
value = div_s64(value, den);
value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
do_sync = 0;
}
return do_sync;
}
void gfs2_quota_unlock(struct gfs2_inode *ip)
{
struct gfs2_alloc *al = ip->i_alloc;
struct gfs2_quota_data *qda[4];
unsigned int count = 0;
unsigned int x;
if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
goto out;
for (x = 0; x < al->al_qd_num; x++) {
struct gfs2_quota_data *qd;
int sync;
qd = al->al_qd[x];
sync = need_sync(qd);
gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
if (sync && qd_trylock(qd))
qda[count++] = qd;
}
if (count) {
do_sync(count, qda);
for (x = 0; x < count; x++)
qd_unlock(qda[x]);
}
out:
gfs2_quota_unhold(ip);
}
#define MAX_LINE 256