linux/fs/xfs/xfs_qm_syscalls.c
Darrick J. Wong 59d7fab2df xfs: fix quotaoff mutex usage now that we don't support disabling it
Prior to commit 40b52225e5 ("xfs: remove support for disabling quota
accounting on a mounted file system"), we used the quotaoff mutex to
protect dquot operations against quotaoff trying to pull down dquots as
part of disabling quota.

Now that we only support turning off quota enforcement, the quotaoff
mutex only protects changes in m_qflags/sb_qflags.  We don't need it to
protect dquots, which means we can remove it from setqlimits and the
dquot scrub code.  While we're at it, fix the function that forces
quotacheck, since it should have been taking the quotaoff mutex.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2021-12-21 09:49:41 -08:00

533 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_quota.h"
#include "xfs_qm.h"
#include "xfs_icache.h"
int
xfs_qm_scall_quotaoff(
xfs_mount_t *mp,
uint flags)
{
/*
* No file system can have quotas enabled on disk but not in core.
* Note that quota utilities (like quotaoff) _expect_
* errno == -EEXIST here.
*/
if ((mp->m_qflags & flags) == 0)
return -EEXIST;
/*
* We do not support actually turning off quota accounting any more.
* Just log a warning and ignore the accounting related flags.
*/
if (flags & XFS_ALL_QUOTA_ACCT)
xfs_info(mp, "disabling of quota accounting not supported.");
mutex_lock(&mp->m_quotainfo->qi_quotaofflock);
mp->m_qflags &= ~(flags & XFS_ALL_QUOTA_ENFD);
spin_lock(&mp->m_sb_lock);
mp->m_sb.sb_qflags = mp->m_qflags;
spin_unlock(&mp->m_sb_lock);
mutex_unlock(&mp->m_quotainfo->qi_quotaofflock);
/* XXX what to do if error ? Revert back to old vals incore ? */
return xfs_sync_sb(mp, false);
}
STATIC int
xfs_qm_scall_trunc_qfile(
struct xfs_mount *mp,
xfs_ino_t ino)
{
struct xfs_inode *ip;
struct xfs_trans *tp;
int error;
if (ino == NULLFSINO)
return 0;
error = xfs_iget(mp, NULL, ino, 0, 0, &ip);
if (error)
return error;
xfs_ilock(ip, XFS_IOLOCK_EXCL);
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
if (error) {
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
goto out_put;
}
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, 0);
ip->i_disk_size = 0;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
if (error) {
xfs_trans_cancel(tp);
goto out_unlock;
}
ASSERT(ip->i_df.if_nextents == 0);
xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
error = xfs_trans_commit(tp);
out_unlock:
xfs_iunlock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
out_put:
xfs_irele(ip);
return error;
}
int
xfs_qm_scall_trunc_qfiles(
xfs_mount_t *mp,
uint flags)
{
int error = -EINVAL;
if (!xfs_has_quota(mp) || flags == 0 ||
(flags & ~XFS_QMOPT_QUOTALL)) {
xfs_debug(mp, "%s: flags=%x m_qflags=%x",
__func__, flags, mp->m_qflags);
return -EINVAL;
}
if (flags & XFS_QMOPT_UQUOTA) {
error = xfs_qm_scall_trunc_qfile(mp, mp->m_sb.sb_uquotino);
if (error)
return error;
}
if (flags & XFS_QMOPT_GQUOTA) {
error = xfs_qm_scall_trunc_qfile(mp, mp->m_sb.sb_gquotino);
if (error)
return error;
}
if (flags & XFS_QMOPT_PQUOTA)
error = xfs_qm_scall_trunc_qfile(mp, mp->m_sb.sb_pquotino);
return error;
}
/*
* Switch on (a given) quota enforcement for a filesystem. This takes
* effect immediately.
* (Switching on quota accounting must be done at mount time.)
*/
int
xfs_qm_scall_quotaon(
xfs_mount_t *mp,
uint flags)
{
int error;
uint qf;
/*
* Switching on quota accounting must be done at mount time,
* only consider quota enforcement stuff here.
*/
flags &= XFS_ALL_QUOTA_ENFD;
if (flags == 0) {
xfs_debug(mp, "%s: zero flags, m_qflags=%x",
__func__, mp->m_qflags);
return -EINVAL;
}
/*
* Can't enforce without accounting. We check the superblock
* qflags here instead of m_qflags because rootfs can have
* quota acct on ondisk without m_qflags' knowing.
*/
if (((mp->m_sb.sb_qflags & XFS_UQUOTA_ACCT) == 0 &&
(flags & XFS_UQUOTA_ENFD)) ||
((mp->m_sb.sb_qflags & XFS_GQUOTA_ACCT) == 0 &&
(flags & XFS_GQUOTA_ENFD)) ||
((mp->m_sb.sb_qflags & XFS_PQUOTA_ACCT) == 0 &&
(flags & XFS_PQUOTA_ENFD))) {
xfs_debug(mp,
"%s: Can't enforce without acct, flags=%x sbflags=%x",
__func__, flags, mp->m_sb.sb_qflags);
return -EINVAL;
}
/*
* If everything's up to-date incore, then don't waste time.
*/
if ((mp->m_qflags & flags) == flags)
return -EEXIST;
/*
* Change sb_qflags on disk but not incore mp->qflags
* if this is the root filesystem.
*/
spin_lock(&mp->m_sb_lock);
qf = mp->m_sb.sb_qflags;
mp->m_sb.sb_qflags = qf | flags;
spin_unlock(&mp->m_sb_lock);
/*
* There's nothing to change if it's the same.
*/
if ((qf & flags) == flags)
return -EEXIST;
error = xfs_sync_sb(mp, false);
if (error)
return error;
/*
* If we aren't trying to switch on quota enforcement, we are done.
*/
if (((mp->m_sb.sb_qflags & XFS_UQUOTA_ACCT) !=
(mp->m_qflags & XFS_UQUOTA_ACCT)) ||
((mp->m_sb.sb_qflags & XFS_PQUOTA_ACCT) !=
(mp->m_qflags & XFS_PQUOTA_ACCT)) ||
((mp->m_sb.sb_qflags & XFS_GQUOTA_ACCT) !=
(mp->m_qflags & XFS_GQUOTA_ACCT)))
return 0;
if (!XFS_IS_QUOTA_ON(mp))
return -ESRCH;
/*
* Switch on quota enforcement in core.
*/
mutex_lock(&mp->m_quotainfo->qi_quotaofflock);
mp->m_qflags |= (flags & XFS_ALL_QUOTA_ENFD);
mutex_unlock(&mp->m_quotainfo->qi_quotaofflock);
return 0;
}
#define XFS_QC_MASK \
(QC_LIMIT_MASK | QC_TIMER_MASK | QC_WARNS_MASK)
/*
* Adjust limits of this quota, and the defaults if passed in. Returns true
* if the new limits made sense and were applied, false otherwise.
*/
static inline bool
xfs_setqlim_limits(
struct xfs_mount *mp,
struct xfs_dquot_res *res,
struct xfs_quota_limits *qlim,
xfs_qcnt_t hard,
xfs_qcnt_t soft,
const char *tag)
{
/* The hard limit can't be less than the soft limit. */
if (hard != 0 && hard < soft) {
xfs_debug(mp, "%shard %lld < %ssoft %lld", tag, hard, tag,
soft);
return false;
}
res->hardlimit = hard;
res->softlimit = soft;
if (qlim) {
qlim->hard = hard;
qlim->soft = soft;
}
return true;
}
static inline void
xfs_setqlim_warns(
struct xfs_dquot_res *res,
struct xfs_quota_limits *qlim,
int warns)
{
res->warnings = warns;
if (qlim)
qlim->warn = warns;
}
static inline void
xfs_setqlim_timer(
struct xfs_mount *mp,
struct xfs_dquot_res *res,
struct xfs_quota_limits *qlim,
s64 timer)
{
if (qlim) {
/* Set the length of the default grace period. */
res->timer = xfs_dquot_set_grace_period(timer);
qlim->time = res->timer;
} else {
/* Set the grace period expiration on a quota. */
res->timer = xfs_dquot_set_timeout(mp, timer);
}
}
/*
* Adjust quota limits, and start/stop timers accordingly.
*/
int
xfs_qm_scall_setqlim(
struct xfs_mount *mp,
xfs_dqid_t id,
xfs_dqtype_t type,
struct qc_dqblk *newlim)
{
struct xfs_quotainfo *q = mp->m_quotainfo;
struct xfs_dquot *dqp;
struct xfs_trans *tp;
struct xfs_def_quota *defq;
struct xfs_dquot_res *res;
struct xfs_quota_limits *qlim;
int error;
xfs_qcnt_t hard, soft;
if (newlim->d_fieldmask & ~XFS_QC_MASK)
return -EINVAL;
if ((newlim->d_fieldmask & XFS_QC_MASK) == 0)
return 0;
/*
* Get the dquot (locked) before we start, as we need to do a
* transaction to allocate it if it doesn't exist. Once we have the
* dquot, unlock it so we can start the next transaction safely. We hold
* a reference to the dquot, so it's safe to do this unlock/lock without
* it being reclaimed in the mean time.
*/
error = xfs_qm_dqget(mp, id, type, true, &dqp);
if (error) {
ASSERT(error != -ENOENT);
return error;
}
defq = xfs_get_defquota(q, xfs_dquot_type(dqp));
xfs_dqunlock(dqp);
error = xfs_trans_alloc(mp, &M_RES(mp)->tr_qm_setqlim, 0, 0, 0, &tp);
if (error)
goto out_rele;
xfs_dqlock(dqp);
xfs_trans_dqjoin(tp, dqp);
/*
* Update quota limits, warnings, and timers, and the defaults
* if we're touching id == 0.
*
* Make sure that hardlimits are >= soft limits before changing.
*
* Update warnings counter(s) if requested.
*
* Timelimits for the super user set the relative time the other users
* can be over quota for this file system. If it is zero a default is
* used. Ditto for the default soft and hard limit values (already
* done, above), and for warnings.
*
* For other IDs, userspace can bump out the grace period if over
* the soft limit.
*/
/* Blocks on the data device. */
hard = (newlim->d_fieldmask & QC_SPC_HARD) ?
(xfs_qcnt_t) XFS_B_TO_FSB(mp, newlim->d_spc_hardlimit) :
dqp->q_blk.hardlimit;
soft = (newlim->d_fieldmask & QC_SPC_SOFT) ?
(xfs_qcnt_t) XFS_B_TO_FSB(mp, newlim->d_spc_softlimit) :
dqp->q_blk.softlimit;
res = &dqp->q_blk;
qlim = id == 0 ? &defq->blk : NULL;
if (xfs_setqlim_limits(mp, res, qlim, hard, soft, "blk"))
xfs_dquot_set_prealloc_limits(dqp);
if (newlim->d_fieldmask & QC_SPC_WARNS)
xfs_setqlim_warns(res, qlim, newlim->d_spc_warns);
if (newlim->d_fieldmask & QC_SPC_TIMER)
xfs_setqlim_timer(mp, res, qlim, newlim->d_spc_timer);
/* Blocks on the realtime device. */
hard = (newlim->d_fieldmask & QC_RT_SPC_HARD) ?
(xfs_qcnt_t) XFS_B_TO_FSB(mp, newlim->d_rt_spc_hardlimit) :
dqp->q_rtb.hardlimit;
soft = (newlim->d_fieldmask & QC_RT_SPC_SOFT) ?
(xfs_qcnt_t) XFS_B_TO_FSB(mp, newlim->d_rt_spc_softlimit) :
dqp->q_rtb.softlimit;
res = &dqp->q_rtb;
qlim = id == 0 ? &defq->rtb : NULL;
xfs_setqlim_limits(mp, res, qlim, hard, soft, "rtb");
if (newlim->d_fieldmask & QC_RT_SPC_WARNS)
xfs_setqlim_warns(res, qlim, newlim->d_rt_spc_warns);
if (newlim->d_fieldmask & QC_RT_SPC_TIMER)
xfs_setqlim_timer(mp, res, qlim, newlim->d_rt_spc_timer);
/* Inodes */
hard = (newlim->d_fieldmask & QC_INO_HARD) ?
(xfs_qcnt_t) newlim->d_ino_hardlimit :
dqp->q_ino.hardlimit;
soft = (newlim->d_fieldmask & QC_INO_SOFT) ?
(xfs_qcnt_t) newlim->d_ino_softlimit :
dqp->q_ino.softlimit;
res = &dqp->q_ino;
qlim = id == 0 ? &defq->ino : NULL;
xfs_setqlim_limits(mp, res, qlim, hard, soft, "ino");
if (newlim->d_fieldmask & QC_INO_WARNS)
xfs_setqlim_warns(res, qlim, newlim->d_ino_warns);
if (newlim->d_fieldmask & QC_INO_TIMER)
xfs_setqlim_timer(mp, res, qlim, newlim->d_ino_timer);
if (id != 0) {
/*
* If the user is now over quota, start the timelimit.
* The user will not be 'warned'.
* Note that we keep the timers ticking, whether enforcement
* is on or off. We don't really want to bother with iterating
* over all ondisk dquots and turning the timers on/off.
*/
xfs_qm_adjust_dqtimers(dqp);
}
dqp->q_flags |= XFS_DQFLAG_DIRTY;
xfs_trans_log_dquot(tp, dqp);
error = xfs_trans_commit(tp);
out_rele:
xfs_qm_dqrele(dqp);
return error;
}
/* Fill out the quota context. */
static void
xfs_qm_scall_getquota_fill_qc(
struct xfs_mount *mp,
xfs_dqtype_t type,
const struct xfs_dquot *dqp,
struct qc_dqblk *dst)
{
memset(dst, 0, sizeof(*dst));
dst->d_spc_hardlimit = XFS_FSB_TO_B(mp, dqp->q_blk.hardlimit);
dst->d_spc_softlimit = XFS_FSB_TO_B(mp, dqp->q_blk.softlimit);
dst->d_ino_hardlimit = dqp->q_ino.hardlimit;
dst->d_ino_softlimit = dqp->q_ino.softlimit;
dst->d_space = XFS_FSB_TO_B(mp, dqp->q_blk.reserved);
dst->d_ino_count = dqp->q_ino.reserved;
dst->d_spc_timer = dqp->q_blk.timer;
dst->d_ino_timer = dqp->q_ino.timer;
dst->d_ino_warns = dqp->q_ino.warnings;
dst->d_spc_warns = dqp->q_blk.warnings;
dst->d_rt_spc_hardlimit = XFS_FSB_TO_B(mp, dqp->q_rtb.hardlimit);
dst->d_rt_spc_softlimit = XFS_FSB_TO_B(mp, dqp->q_rtb.softlimit);
dst->d_rt_space = XFS_FSB_TO_B(mp, dqp->q_rtb.reserved);
dst->d_rt_spc_timer = dqp->q_rtb.timer;
dst->d_rt_spc_warns = dqp->q_rtb.warnings;
/*
* Internally, we don't reset all the timers when quota enforcement
* gets turned off. No need to confuse the user level code,
* so return zeroes in that case.
*/
if (!xfs_dquot_is_enforced(dqp)) {
dst->d_spc_timer = 0;
dst->d_ino_timer = 0;
dst->d_rt_spc_timer = 0;
}
#ifdef DEBUG
if (xfs_dquot_is_enforced(dqp) && dqp->q_id != 0) {
if ((dst->d_space > dst->d_spc_softlimit) &&
(dst->d_spc_softlimit > 0)) {
ASSERT(dst->d_spc_timer != 0);
}
if ((dst->d_ino_count > dqp->q_ino.softlimit) &&
(dqp->q_ino.softlimit > 0)) {
ASSERT(dst->d_ino_timer != 0);
}
}
#endif
}
/* Return the quota information for the dquot matching id. */
int
xfs_qm_scall_getquota(
struct xfs_mount *mp,
xfs_dqid_t id,
xfs_dqtype_t type,
struct qc_dqblk *dst)
{
struct xfs_dquot *dqp;
int error;
/* Flush inodegc work at the start of a quota reporting scan. */
if (id == 0)
xfs_inodegc_flush(mp);
/*
* Try to get the dquot. We don't want it allocated on disk, so don't
* set doalloc. If it doesn't exist, we'll get ENOENT back.
*/
error = xfs_qm_dqget(mp, id, type, false, &dqp);
if (error)
return error;
/*
* If everything's NULL, this dquot doesn't quite exist as far as
* our utility programs are concerned.
*/
if (XFS_IS_DQUOT_UNINITIALIZED(dqp)) {
error = -ENOENT;
goto out_put;
}
xfs_qm_scall_getquota_fill_qc(mp, type, dqp, dst);
out_put:
xfs_qm_dqput(dqp);
return error;
}
/*
* Return the quota information for the first initialized dquot whose id
* is at least as high as id.
*/
int
xfs_qm_scall_getquota_next(
struct xfs_mount *mp,
xfs_dqid_t *id,
xfs_dqtype_t type,
struct qc_dqblk *dst)
{
struct xfs_dquot *dqp;
int error;
/* Flush inodegc work at the start of a quota reporting scan. */
if (*id == 0)
xfs_inodegc_flush(mp);
error = xfs_qm_dqget_next(mp, *id, type, &dqp);
if (error)
return error;
/* Fill in the ID we actually read from disk */
*id = dqp->q_id;
xfs_qm_scall_getquota_fill_qc(mp, type, dqp, dst);
xfs_qm_dqput(dqp);
return error;
}