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xfs_dquot.c
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xfs_dquot.c
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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2003 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_shared.h"
#include "xfs_trans_resv.h"
#include "xfs_bit.h"
#include "xfs_mount.h"
#include "xfs_defer.h"
#include "xfs_inode.h"
#include "xfs_bmap.h"
#include "xfs_quota.h"
#include "xfs_trans.h"
#include "xfs_buf_item.h"
#include "xfs_trans_space.h"
#include "xfs_trans_priv.h"
#include "xfs_qm.h"
#include "xfs_trace.h"
#include "xfs_log.h"
#include "xfs_bmap_btree.h"
/*
* Lock order:
*
* ip->i_lock
* qi->qi_tree_lock
* dquot->q_qlock (xfs_dqlock() and friends)
* dquot->q_flush (xfs_dqflock() and friends)
* qi->qi_lru_lock
*
* If two dquots need to be locked the order is user before group/project,
* otherwise by the lowest id first, see xfs_dqlock2.
*/
struct kmem_zone *xfs_qm_dqtrxzone;
static struct kmem_zone *xfs_qm_dqzone;
static struct lock_class_key xfs_dquot_group_class;
static struct lock_class_key xfs_dquot_project_class;
/*
* This is called to free all the memory associated with a dquot
*/
void
xfs_qm_dqdestroy(
struct xfs_dquot *dqp)
{
ASSERT(list_empty(&dqp->q_lru));
kmem_free(dqp->q_logitem.qli_item.li_lv_shadow);
mutex_destroy(&dqp->q_qlock);
XFS_STATS_DEC(dqp->q_mount, xs_qm_dquot);
kmem_cache_free(xfs_qm_dqzone, dqp);
}
/*
* If default limits are in force, push them into the dquot now.
* We overwrite the dquot limits only if they are zero and this
* is not the root dquot.
*/
void
xfs_qm_adjust_dqlimits(
struct xfs_mount *mp,
struct xfs_dquot *dq)
{
struct xfs_quotainfo *q = mp->m_quotainfo;
struct xfs_disk_dquot *d = &dq->q_core;
struct xfs_def_quota *defq;
int prealloc = 0;
ASSERT(d->d_id);
defq = xfs_get_defquota(dq, q);
if (defq->bsoftlimit && !d->d_blk_softlimit) {
d->d_blk_softlimit = cpu_to_be64(defq->bsoftlimit);
prealloc = 1;
}
if (defq->bhardlimit && !d->d_blk_hardlimit) {
d->d_blk_hardlimit = cpu_to_be64(defq->bhardlimit);
prealloc = 1;
}
if (defq->isoftlimit && !d->d_ino_softlimit)
d->d_ino_softlimit = cpu_to_be64(defq->isoftlimit);
if (defq->ihardlimit && !d->d_ino_hardlimit)
d->d_ino_hardlimit = cpu_to_be64(defq->ihardlimit);
if (defq->rtbsoftlimit && !d->d_rtb_softlimit)
d->d_rtb_softlimit = cpu_to_be64(defq->rtbsoftlimit);
if (defq->rtbhardlimit && !d->d_rtb_hardlimit)
d->d_rtb_hardlimit = cpu_to_be64(defq->rtbhardlimit);
if (prealloc)
xfs_dquot_set_prealloc_limits(dq);
}
/*
* Check the limits and timers of a dquot and start or reset timers
* if necessary.
* This gets called even when quota enforcement is OFF, which makes our
* life a little less complicated. (We just don't reject any quota
* reservations in that case, when enforcement is off).
* We also return 0 as the values of the timers in Q_GETQUOTA calls, when
* enforcement's off.
* In contrast, warnings are a little different in that they don't
* 'automatically' get started when limits get exceeded. They do
* get reset to zero, however, when we find the count to be under
* the soft limit (they are only ever set non-zero via userspace).
*/
void
xfs_qm_adjust_dqtimers(
struct xfs_mount *mp,
struct xfs_disk_dquot *d)
{
ASSERT(d->d_id);
#ifdef DEBUG
if (d->d_blk_hardlimit)
ASSERT(be64_to_cpu(d->d_blk_softlimit) <=
be64_to_cpu(d->d_blk_hardlimit));
if (d->d_ino_hardlimit)
ASSERT(be64_to_cpu(d->d_ino_softlimit) <=
be64_to_cpu(d->d_ino_hardlimit));
if (d->d_rtb_hardlimit)
ASSERT(be64_to_cpu(d->d_rtb_softlimit) <=
be64_to_cpu(d->d_rtb_hardlimit));
#endif
if (!d->d_btimer) {
if ((d->d_blk_softlimit &&
(be64_to_cpu(d->d_bcount) >
be64_to_cpu(d->d_blk_softlimit))) ||
(d->d_blk_hardlimit &&
(be64_to_cpu(d->d_bcount) >
be64_to_cpu(d->d_blk_hardlimit)))) {
d->d_btimer = cpu_to_be32(ktime_get_real_seconds() +
mp->m_quotainfo->qi_btimelimit);
} else {
d->d_bwarns = 0;
}
} else {
if ((!d->d_blk_softlimit ||
(be64_to_cpu(d->d_bcount) <=
be64_to_cpu(d->d_blk_softlimit))) &&
(!d->d_blk_hardlimit ||
(be64_to_cpu(d->d_bcount) <=
be64_to_cpu(d->d_blk_hardlimit)))) {
d->d_btimer = 0;
}
}
if (!d->d_itimer) {
if ((d->d_ino_softlimit &&
(be64_to_cpu(d->d_icount) >
be64_to_cpu(d->d_ino_softlimit))) ||
(d->d_ino_hardlimit &&
(be64_to_cpu(d->d_icount) >
be64_to_cpu(d->d_ino_hardlimit)))) {
d->d_itimer = cpu_to_be32(ktime_get_real_seconds() +
mp->m_quotainfo->qi_itimelimit);
} else {
d->d_iwarns = 0;
}
} else {
if ((!d->d_ino_softlimit ||
(be64_to_cpu(d->d_icount) <=
be64_to_cpu(d->d_ino_softlimit))) &&
(!d->d_ino_hardlimit ||
(be64_to_cpu(d->d_icount) <=
be64_to_cpu(d->d_ino_hardlimit)))) {
d->d_itimer = 0;
}
}
if (!d->d_rtbtimer) {
if ((d->d_rtb_softlimit &&
(be64_to_cpu(d->d_rtbcount) >
be64_to_cpu(d->d_rtb_softlimit))) ||
(d->d_rtb_hardlimit &&
(be64_to_cpu(d->d_rtbcount) >
be64_to_cpu(d->d_rtb_hardlimit)))) {
d->d_rtbtimer = cpu_to_be32(ktime_get_real_seconds() +
mp->m_quotainfo->qi_rtbtimelimit);
} else {
d->d_rtbwarns = 0;
}
} else {
if ((!d->d_rtb_softlimit ||
(be64_to_cpu(d->d_rtbcount) <=
be64_to_cpu(d->d_rtb_softlimit))) &&
(!d->d_rtb_hardlimit ||
(be64_to_cpu(d->d_rtbcount) <=
be64_to_cpu(d->d_rtb_hardlimit)))) {
d->d_rtbtimer = 0;
}
}
}
/*
* initialize a buffer full of dquots and log the whole thing
*/
STATIC void
xfs_qm_init_dquot_blk(
xfs_trans_t *tp,
xfs_mount_t *mp,
xfs_dqid_t id,
uint type,
xfs_buf_t *bp)
{
struct xfs_quotainfo *q = mp->m_quotainfo;
xfs_dqblk_t *d;
xfs_dqid_t curid;
int i;
ASSERT(tp);
ASSERT(xfs_buf_islocked(bp));
d = bp->b_addr;
/*
* ID of the first dquot in the block - id's are zero based.
*/
curid = id - (id % q->qi_dqperchunk);
memset(d, 0, BBTOB(q->qi_dqchunklen));
for (i = 0; i < q->qi_dqperchunk; i++, d++, curid++) {
d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
d->dd_diskdq.d_id = cpu_to_be32(curid);
d->dd_diskdq.d_flags = type;
if (xfs_sb_version_hascrc(&mp->m_sb)) {
uuid_copy(&d->dd_uuid, &mp->m_sb.sb_meta_uuid);
xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
XFS_DQUOT_CRC_OFF);
}
}
xfs_trans_dquot_buf(tp, bp,
(type & XFS_DQ_USER ? XFS_BLF_UDQUOT_BUF :
((type & XFS_DQ_PROJ) ? XFS_BLF_PDQUOT_BUF :
XFS_BLF_GDQUOT_BUF)));
xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1);
}
/*
* Initialize the dynamic speculative preallocation thresholds. The lo/hi
* watermarks correspond to the soft and hard limits by default. If a soft limit
* is not specified, we use 95% of the hard limit.
*/
void
xfs_dquot_set_prealloc_limits(struct xfs_dquot *dqp)
{
uint64_t space;
dqp->q_prealloc_hi_wmark = be64_to_cpu(dqp->q_core.d_blk_hardlimit);
dqp->q_prealloc_lo_wmark = be64_to_cpu(dqp->q_core.d_blk_softlimit);
if (!dqp->q_prealloc_lo_wmark) {
dqp->q_prealloc_lo_wmark = dqp->q_prealloc_hi_wmark;
do_div(dqp->q_prealloc_lo_wmark, 100);
dqp->q_prealloc_lo_wmark *= 95;
}
space = dqp->q_prealloc_hi_wmark;
do_div(space, 100);
dqp->q_low_space[XFS_QLOWSP_1_PCNT] = space;
dqp->q_low_space[XFS_QLOWSP_3_PCNT] = space * 3;
dqp->q_low_space[XFS_QLOWSP_5_PCNT] = space * 5;
}
/*
* Ensure that the given in-core dquot has a buffer on disk backing it, and
* return the buffer locked and held. This is called when the bmapi finds a
* hole.
*/
STATIC int
xfs_dquot_disk_alloc(
struct xfs_trans **tpp,
struct xfs_dquot *dqp,
struct xfs_buf **bpp)
{
struct xfs_bmbt_irec map;
struct xfs_trans *tp = *tpp;
struct xfs_mount *mp = tp->t_mountp;
struct xfs_buf *bp;
struct xfs_inode *quotip = xfs_quota_inode(mp, dqp->dq_flags);
int nmaps = 1;
int error;
trace_xfs_dqalloc(dqp);
xfs_ilock(quotip, XFS_ILOCK_EXCL);
if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) {
/*
* Return if this type of quotas is turned off while we didn't
* have an inode lock
*/
xfs_iunlock(quotip, XFS_ILOCK_EXCL);
return -ESRCH;
}
/* Create the block mapping. */
xfs_trans_ijoin(tp, quotip, XFS_ILOCK_EXCL);
error = xfs_bmapi_write(tp, quotip, dqp->q_fileoffset,
XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA, 0, &map,
&nmaps);
if (error)
return error;
ASSERT(map.br_blockcount == XFS_DQUOT_CLUSTER_SIZE_FSB);
ASSERT(nmaps == 1);
ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
(map.br_startblock != HOLESTARTBLOCK));
/*
* Keep track of the blkno to save a lookup later
*/
dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
/* now we can just get the buffer (there's nothing to read yet) */
error = xfs_trans_get_buf(tp, mp->m_ddev_targp, dqp->q_blkno,
mp->m_quotainfo->qi_dqchunklen, 0, &bp);
if (error)
return error;
bp->b_ops = &xfs_dquot_buf_ops;
/*
* Make a chunk of dquots out of this buffer and log
* the entire thing.
*/
xfs_qm_init_dquot_blk(tp, mp, be32_to_cpu(dqp->q_core.d_id),
dqp->dq_flags & XFS_DQ_ALLTYPES, bp);
xfs_buf_set_ref(bp, XFS_DQUOT_REF);
/*
* Hold the buffer and join it to the dfops so that we'll still own
* the buffer when we return to the caller. The buffer disposal on
* error must be paid attention to very carefully, as it has been
* broken since commit efa092f3d4c6 "[XFS] Fixes a bug in the quota
* code when allocating a new dquot record" in 2005, and the later
* conversion to xfs_defer_ops in commit 310a75a3c6c747 failed to keep
* the buffer locked across the _defer_finish call. We can now do
* this correctly with xfs_defer_bjoin.
*
* Above, we allocated a disk block for the dquot information and used
* get_buf to initialize the dquot. If the _defer_finish fails, the old
* transaction is gone but the new buffer is not joined or held to any
* transaction, so we must _buf_relse it.
*
* If everything succeeds, the caller of this function is returned a
* buffer that is locked and held to the transaction. The caller
* is responsible for unlocking any buffer passed back, either
* manually or by committing the transaction. On error, the buffer is
* released and not passed back.
*/
xfs_trans_bhold(tp, bp);
error = xfs_defer_finish(tpp);
if (error) {
xfs_trans_bhold_release(*tpp, bp);
xfs_trans_brelse(*tpp, bp);
return error;
}
*bpp = bp;
return 0;
}
/*
* Read in the in-core dquot's on-disk metadata and return the buffer.
* Returns ENOENT to signal a hole.
*/
STATIC int
xfs_dquot_disk_read(
struct xfs_mount *mp,
struct xfs_dquot *dqp,
struct xfs_buf **bpp)
{
struct xfs_bmbt_irec map;
struct xfs_buf *bp;
struct xfs_inode *quotip = xfs_quota_inode(mp, dqp->dq_flags);
uint lock_mode;
int nmaps = 1;
int error;
lock_mode = xfs_ilock_data_map_shared(quotip);
if (!xfs_this_quota_on(mp, dqp->dq_flags)) {
/*
* Return if this type of quotas is turned off while we
* didn't have the quota inode lock.
*/
xfs_iunlock(quotip, lock_mode);
return -ESRCH;
}
/*
* Find the block map; no allocations yet
*/
error = xfs_bmapi_read(quotip, dqp->q_fileoffset,
XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0);
xfs_iunlock(quotip, lock_mode);
if (error)
return error;
ASSERT(nmaps == 1);
ASSERT(map.br_blockcount >= 1);
ASSERT(map.br_startblock != DELAYSTARTBLOCK);
if (map.br_startblock == HOLESTARTBLOCK)
return -ENOENT;
trace_xfs_dqtobp_read(dqp);
/*
* store the blkno etc so that we don't have to do the
* mapping all the time
*/
dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno,
mp->m_quotainfo->qi_dqchunklen, 0, &bp,
&xfs_dquot_buf_ops);
if (error) {
ASSERT(bp == NULL);
return error;
}
ASSERT(xfs_buf_islocked(bp));
xfs_buf_set_ref(bp, XFS_DQUOT_REF);
*bpp = bp;
return 0;
}
/* Allocate and initialize everything we need for an incore dquot. */
STATIC struct xfs_dquot *
xfs_dquot_alloc(
struct xfs_mount *mp,
xfs_dqid_t id,
uint type)
{
struct xfs_dquot *dqp;
dqp = kmem_zone_zalloc(xfs_qm_dqzone, 0);
dqp->dq_flags = type;
dqp->q_core.d_id = cpu_to_be32(id);
dqp->q_mount = mp;
INIT_LIST_HEAD(&dqp->q_lru);
mutex_init(&dqp->q_qlock);
init_waitqueue_head(&dqp->q_pinwait);
dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
/*
* Offset of dquot in the (fixed sized) dquot chunk.
*/
dqp->q_bufoffset = (id % mp->m_quotainfo->qi_dqperchunk) *
sizeof(xfs_dqblk_t);
/*
* Because we want to use a counting completion, complete
* the flush completion once to allow a single access to
* the flush completion without blocking.
*/
init_completion(&dqp->q_flush);
complete(&dqp->q_flush);
/*
* Make sure group quotas have a different lock class than user
* quotas.
*/
switch (type) {
case XFS_DQ_USER:
/* uses the default lock class */
break;
case XFS_DQ_GROUP:
lockdep_set_class(&dqp->q_qlock, &xfs_dquot_group_class);
break;
case XFS_DQ_PROJ:
lockdep_set_class(&dqp->q_qlock, &xfs_dquot_project_class);
break;
default:
ASSERT(0);
break;
}
xfs_qm_dquot_logitem_init(dqp);
XFS_STATS_INC(mp, xs_qm_dquot);
return dqp;
}
/* Copy the in-core quota fields in from the on-disk buffer. */
STATIC void
xfs_dquot_from_disk(
struct xfs_dquot *dqp,
struct xfs_buf *bp)
{
struct xfs_disk_dquot *ddqp = bp->b_addr + dqp->q_bufoffset;
/* copy everything from disk dquot to the incore dquot */
memcpy(&dqp->q_core, ddqp, sizeof(struct xfs_disk_dquot));
/*
* Reservation counters are defined as reservation plus current usage
* to avoid having to add every time.
*/
dqp->q_res_bcount = be64_to_cpu(ddqp->d_bcount);
dqp->q_res_icount = be64_to_cpu(ddqp->d_icount);
dqp->q_res_rtbcount = be64_to_cpu(ddqp->d_rtbcount);
/* initialize the dquot speculative prealloc thresholds */
xfs_dquot_set_prealloc_limits(dqp);
}
/* Allocate and initialize the dquot buffer for this in-core dquot. */
static int
xfs_qm_dqread_alloc(
struct xfs_mount *mp,
struct xfs_dquot *dqp,
struct xfs_buf **bpp)
{
struct xfs_trans *tp;
int error;
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_qm_dqalloc,
XFS_QM_DQALLOC_SPACE_RES(mp), 0, 0, &tp);
if (error)
goto err;
error = xfs_dquot_disk_alloc(&tp, dqp, bpp);
if (error)
goto err_cancel;
error = xfs_trans_commit(tp);
if (error) {
/*
* Buffer was held to the transaction, so we have to unlock it
* manually here because we're not passing it back.
*/
xfs_buf_relse(*bpp);
*bpp = NULL;
goto err;
}
return 0;
err_cancel:
xfs_trans_cancel(tp);
err:
return error;
}
/*
* Read in the ondisk dquot using dqtobp() then copy it to an incore version,
* and release the buffer immediately. If @can_alloc is true, fill any
* holes in the on-disk metadata.
*/
static int
xfs_qm_dqread(
struct xfs_mount *mp,
xfs_dqid_t id,
uint type,
bool can_alloc,
struct xfs_dquot **dqpp)
{
struct xfs_dquot *dqp;
struct xfs_buf *bp;
int error;
dqp = xfs_dquot_alloc(mp, id, type);
trace_xfs_dqread(dqp);
/* Try to read the buffer, allocating if necessary. */
error = xfs_dquot_disk_read(mp, dqp, &bp);
if (error == -ENOENT && can_alloc)
error = xfs_qm_dqread_alloc(mp, dqp, &bp);
if (error)
goto err;
/*
* At this point we should have a clean locked buffer. Copy the data
* to the incore dquot and release the buffer since the incore dquot
* has its own locking protocol so we needn't tie up the buffer any
* further.
*/
ASSERT(xfs_buf_islocked(bp));
xfs_dquot_from_disk(dqp, bp);
xfs_buf_relse(bp);
*dqpp = dqp;
return error;
err:
trace_xfs_dqread_fail(dqp);
xfs_qm_dqdestroy(dqp);
*dqpp = NULL;
return error;
}
/*
* Advance to the next id in the current chunk, or if at the
* end of the chunk, skip ahead to first id in next allocated chunk
* using the SEEK_DATA interface.
*/
static int
xfs_dq_get_next_id(
struct xfs_mount *mp,
uint type,
xfs_dqid_t *id)
{
struct xfs_inode *quotip = xfs_quota_inode(mp, type);
xfs_dqid_t next_id = *id + 1; /* simple advance */
uint lock_flags;
struct xfs_bmbt_irec got;
struct xfs_iext_cursor cur;
xfs_fsblock_t start;
int error = 0;
/* If we'd wrap past the max ID, stop */
if (next_id < *id)
return -ENOENT;
/* If new ID is within the current chunk, advancing it sufficed */
if (next_id % mp->m_quotainfo->qi_dqperchunk) {
*id = next_id;
return 0;
}
/* Nope, next_id is now past the current chunk, so find the next one */
start = (xfs_fsblock_t)next_id / mp->m_quotainfo->qi_dqperchunk;
lock_flags = xfs_ilock_data_map_shared(quotip);
if (!(quotip->i_df.if_flags & XFS_IFEXTENTS)) {
error = xfs_iread_extents(NULL, quotip, XFS_DATA_FORK);
if (error)
return error;
}
if (xfs_iext_lookup_extent(quotip, "ip->i_df, start, &cur, &got)) {
/* contiguous chunk, bump startoff for the id calculation */
if (got.br_startoff < start)
got.br_startoff = start;
*id = got.br_startoff * mp->m_quotainfo->qi_dqperchunk;
} else {
error = -ENOENT;
}
xfs_iunlock(quotip, lock_flags);
return error;
}
/*
* Look up the dquot in the in-core cache. If found, the dquot is returned
* locked and ready to go.
*/
static struct xfs_dquot *
xfs_qm_dqget_cache_lookup(
struct xfs_mount *mp,
struct xfs_quotainfo *qi,
struct radix_tree_root *tree,
xfs_dqid_t id)
{
struct xfs_dquot *dqp;
restart:
mutex_lock(&qi->qi_tree_lock);
dqp = radix_tree_lookup(tree, id);
if (!dqp) {
mutex_unlock(&qi->qi_tree_lock);
XFS_STATS_INC(mp, xs_qm_dqcachemisses);
return NULL;
}
xfs_dqlock(dqp);
if (dqp->dq_flags & XFS_DQ_FREEING) {
xfs_dqunlock(dqp);
mutex_unlock(&qi->qi_tree_lock);
trace_xfs_dqget_freeing(dqp);
delay(1);
goto restart;
}
dqp->q_nrefs++;
mutex_unlock(&qi->qi_tree_lock);
trace_xfs_dqget_hit(dqp);
XFS_STATS_INC(mp, xs_qm_dqcachehits);
return dqp;
}
/*
* Try to insert a new dquot into the in-core cache. If an error occurs the
* caller should throw away the dquot and start over. Otherwise, the dquot
* is returned locked (and held by the cache) as if there had been a cache
* hit.
*/
static int
xfs_qm_dqget_cache_insert(
struct xfs_mount *mp,
struct xfs_quotainfo *qi,
struct radix_tree_root *tree,
xfs_dqid_t id,
struct xfs_dquot *dqp)
{
int error;
mutex_lock(&qi->qi_tree_lock);
error = radix_tree_insert(tree, id, dqp);
if (unlikely(error)) {
/* Duplicate found! Caller must try again. */
WARN_ON(error != -EEXIST);
mutex_unlock(&qi->qi_tree_lock);
trace_xfs_dqget_dup(dqp);
return error;
}
/* Return a locked dquot to the caller, with a reference taken. */
xfs_dqlock(dqp);
dqp->q_nrefs = 1;
qi->qi_dquots++;
mutex_unlock(&qi->qi_tree_lock);
return 0;
}
/* Check our input parameters. */
static int
xfs_qm_dqget_checks(
struct xfs_mount *mp,
uint type)
{
if (WARN_ON_ONCE(!XFS_IS_QUOTA_RUNNING(mp)))
return -ESRCH;
switch (type) {
case XFS_DQ_USER:
if (!XFS_IS_UQUOTA_ON(mp))
return -ESRCH;
return 0;
case XFS_DQ_GROUP:
if (!XFS_IS_GQUOTA_ON(mp))
return -ESRCH;
return 0;
case XFS_DQ_PROJ:
if (!XFS_IS_PQUOTA_ON(mp))
return -ESRCH;
return 0;
default:
WARN_ON_ONCE(0);
return -EINVAL;
}
}
/*
* Given the file system, id, and type (UDQUOT/GDQUOT), return a a locked
* dquot, doing an allocation (if requested) as needed.
*/
int
xfs_qm_dqget(
struct xfs_mount *mp,
xfs_dqid_t id,
uint type,
bool can_alloc,
struct xfs_dquot **O_dqpp)
{
struct xfs_quotainfo *qi = mp->m_quotainfo;
struct radix_tree_root *tree = xfs_dquot_tree(qi, type);
struct xfs_dquot *dqp;
int error;
error = xfs_qm_dqget_checks(mp, type);
if (error)
return error;
restart:
dqp = xfs_qm_dqget_cache_lookup(mp, qi, tree, id);
if (dqp) {
*O_dqpp = dqp;
return 0;
}
error = xfs_qm_dqread(mp, id, type, can_alloc, &dqp);
if (error)
return error;
error = xfs_qm_dqget_cache_insert(mp, qi, tree, id, dqp);
if (error) {
/*
* Duplicate found. Just throw away the new dquot and start
* over.
*/
xfs_qm_dqdestroy(dqp);
XFS_STATS_INC(mp, xs_qm_dquot_dups);
goto restart;
}
trace_xfs_dqget_miss(dqp);
*O_dqpp = dqp;
return 0;
}
/*
* Given a dquot id and type, read and initialize a dquot from the on-disk
* metadata. This function is only for use during quota initialization so
* it ignores the dquot cache assuming that the dquot shrinker isn't set up.
* The caller is responsible for _qm_dqdestroy'ing the returned dquot.
*/
int
xfs_qm_dqget_uncached(
struct xfs_mount *mp,
xfs_dqid_t id,
uint type,
struct xfs_dquot **dqpp)
{
int error;
error = xfs_qm_dqget_checks(mp, type);
if (error)
return error;
return xfs_qm_dqread(mp, id, type, 0, dqpp);
}
/* Return the quota id for a given inode and type. */
xfs_dqid_t
xfs_qm_id_for_quotatype(
struct xfs_inode *ip,
uint type)
{
switch (type) {
case XFS_DQ_USER:
return i_uid_read(VFS_I(ip));
case XFS_DQ_GROUP:
return i_gid_read(VFS_I(ip));
case XFS_DQ_PROJ:
return ip->i_d.di_projid;
}
ASSERT(0);
return 0;
}
/*
* Return the dquot for a given inode and type. If @can_alloc is true, then
* allocate blocks if needed. The inode's ILOCK must be held and it must not
* have already had an inode attached.
*/
int
xfs_qm_dqget_inode(
struct xfs_inode *ip,
uint type,
bool can_alloc,
struct xfs_dquot **O_dqpp)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_quotainfo *qi = mp->m_quotainfo;
struct radix_tree_root *tree = xfs_dquot_tree(qi, type);
struct xfs_dquot *dqp;
xfs_dqid_t id;
int error;
error = xfs_qm_dqget_checks(mp, type);
if (error)
return error;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(xfs_inode_dquot(ip, type) == NULL);
id = xfs_qm_id_for_quotatype(ip, type);
restart:
dqp = xfs_qm_dqget_cache_lookup(mp, qi, tree, id);
if (dqp) {
*O_dqpp = dqp;
return 0;
}
/*
* Dquot cache miss. We don't want to keep the inode lock across
* a (potential) disk read. Also we don't want to deal with the lock
* ordering between quotainode and this inode. OTOH, dropping the inode
* lock here means dealing with a chown that can happen before
* we re-acquire the lock.
*/
xfs_iunlock(ip, XFS_ILOCK_EXCL);
error = xfs_qm_dqread(mp, id, type, can_alloc, &dqp);
xfs_ilock(ip, XFS_ILOCK_EXCL);
if (error)
return error;
/*
* A dquot could be attached to this inode by now, since we had
* dropped the ilock.
*/
if (xfs_this_quota_on(mp, type)) {
struct xfs_dquot *dqp1;
dqp1 = xfs_inode_dquot(ip, type);
if (dqp1) {
xfs_qm_dqdestroy(dqp);
dqp = dqp1;
xfs_dqlock(dqp);
goto dqret;
}
} else {
/* inode stays locked on return */
xfs_qm_dqdestroy(dqp);
return -ESRCH;
}
error = xfs_qm_dqget_cache_insert(mp, qi, tree, id, dqp);
if (error) {
/*
* Duplicate found. Just throw away the new dquot and start
* over.
*/
xfs_qm_dqdestroy(dqp);
XFS_STATS_INC(mp, xs_qm_dquot_dups);
goto restart;
}
dqret:
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
trace_xfs_dqget_miss(dqp);
*O_dqpp = dqp;
return 0;
}
/*
* Starting at @id and progressing upwards, look for an initialized incore
* dquot, lock it, and return it.
*/
int
xfs_qm_dqget_next(
struct xfs_mount *mp,
xfs_dqid_t id,
uint type,
struct xfs_dquot **dqpp)
{
struct xfs_dquot *dqp;
int error = 0;
*dqpp = NULL;
for (; !error; error = xfs_dq_get_next_id(mp, type, &id)) {
error = xfs_qm_dqget(mp, id, type, false, &dqp);
if (error == -ENOENT)
continue;
else if (error != 0)
break;
if (!XFS_IS_DQUOT_UNINITIALIZED(dqp)) {
*dqpp = dqp;
return 0;
}
xfs_qm_dqput(dqp);
}
return error;
}
/*
* Release a reference to the dquot (decrement ref-count) and unlock it.
*
* If there is a group quota attached to this dquot, carefully release that
* too without tripping over deadlocks'n'stuff.
*/
void
xfs_qm_dqput(
struct xfs_dquot *dqp)
{
ASSERT(dqp->q_nrefs > 0);
ASSERT(XFS_DQ_IS_LOCKED(dqp));
trace_xfs_dqput(dqp);
if (--dqp->q_nrefs == 0) {
struct xfs_quotainfo *qi = dqp->q_mount->m_quotainfo;
trace_xfs_dqput_free(dqp);
if (list_lru_add(&qi->qi_lru, &dqp->q_lru))
XFS_STATS_INC(dqp->q_mount, xs_qm_dquot_unused);
}
xfs_dqunlock(dqp);
}
/*
* Release a dquot. Flush it if dirty, then dqput() it.
* dquot must not be locked.
*/
void
xfs_qm_dqrele(
struct xfs_dquot *dqp)
{
if (!dqp)
return;
trace_xfs_dqrele(dqp);
xfs_dqlock(dqp);
/*