diff options
Diffstat (limited to 'fs/xfs/xfs_dquot.c')
| -rw-r--r-- | fs/xfs/xfs_dquot.c | 1105 | 
1 files changed, 1105 insertions, 0 deletions
diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c new file mode 100644 index 00000000000..3ee0cd43edc --- /dev/null +++ b/fs/xfs/xfs_dquot.c @@ -0,0 +1,1105 @@ +/* + * Copyright (c) 2000-2003 Silicon Graphics, Inc. + * 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 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would 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 the Free Software Foundation, + * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA + */ +#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_sb.h" +#include "xfs_ag.h" +#include "xfs_mount.h" +#include "xfs_inode.h" +#include "xfs_bmap.h" +#include "xfs_bmap_util.h" +#include "xfs_alloc.h" +#include "xfs_quota.h" +#include "xfs_error.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_cksum.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. + */ + +#ifdef DEBUG +xfs_buftarg_t *xfs_dqerror_target; +int xfs_do_dqerror; +int xfs_dqreq_num; +int xfs_dqerror_mod = 33; +#endif + +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( +	xfs_dquot_t	*dqp) +{ +	ASSERT(list_empty(&dqp->q_lru)); + +	mutex_destroy(&dqp->q_qlock); +	kmem_zone_free(xfs_qm_dqzone, dqp); + +	XFS_STATS_DEC(xs_qm_dquot); +} + +/* + * 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; +	int			prealloc = 0; + +	ASSERT(d->d_id); + +	if (q->qi_bsoftlimit && !d->d_blk_softlimit) { +		d->d_blk_softlimit = cpu_to_be64(q->qi_bsoftlimit); +		prealloc = 1; +	} +	if (q->qi_bhardlimit && !d->d_blk_hardlimit) { +		d->d_blk_hardlimit = cpu_to_be64(q->qi_bhardlimit); +		prealloc = 1; +	} +	if (q->qi_isoftlimit && !d->d_ino_softlimit) +		d->d_ino_softlimit = cpu_to_be64(q->qi_isoftlimit); +	if (q->qi_ihardlimit && !d->d_ino_hardlimit) +		d->d_ino_hardlimit = cpu_to_be64(q->qi_ihardlimit); +	if (q->qi_rtbsoftlimit && !d->d_rtb_softlimit) +		d->d_rtb_softlimit = cpu_to_be64(q->qi_rtbsoftlimit); +	if (q->qi_rtbhardlimit && !d->d_rtb_hardlimit) +		d->d_rtb_hardlimit = cpu_to_be64(q->qi_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( +	xfs_mount_t		*mp, +	xfs_disk_dquot_t	*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(get_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(get_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(get_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; +	int		curid, 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); +	ASSERT(curid >= 0); +	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_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; +} + +/* + * Allocate a block and fill it with dquots. + * This is called when the bmapi finds a hole. + */ +STATIC int +xfs_qm_dqalloc( +	xfs_trans_t	**tpp, +	xfs_mount_t	*mp, +	xfs_dquot_t	*dqp, +	xfs_inode_t	*quotip, +	xfs_fileoff_t	offset_fsb, +	xfs_buf_t	**O_bpp) +{ +	xfs_fsblock_t	firstblock; +	xfs_bmap_free_t flist; +	xfs_bmbt_irec_t map; +	int		nmaps, error, committed; +	xfs_buf_t	*bp; +	xfs_trans_t	*tp = *tpp; + +	ASSERT(tp != NULL); + +	trace_xfs_dqalloc(dqp); + +	/* +	 * Initialize the bmap freelist prior to calling bmapi code. +	 */ +	xfs_bmap_init(&flist, &firstblock); +	xfs_ilock(quotip, XFS_ILOCK_EXCL); +	/* +	 * Return if this type of quotas is turned off while we didn't +	 * have an inode lock +	 */ +	if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) { +		xfs_iunlock(quotip, XFS_ILOCK_EXCL); +		return (ESRCH); +	} + +	xfs_trans_ijoin(tp, quotip, XFS_ILOCK_EXCL); +	nmaps = 1; +	error = xfs_bmapi_write(tp, quotip, offset_fsb, +				XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA, +				&firstblock, XFS_QM_DQALLOC_SPACE_RES(mp), +				&map, &nmaps, &flist); +	if (error) +		goto error0; +	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) */ +	bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, +			       dqp->q_blkno, +			       mp->m_quotainfo->qi_dqchunklen, +			       0); +	if (!bp) { +		error = ENOMEM; +		goto error1; +	} +	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_bmap_finish() may commit the current transaction and +	 * start a second transaction if the freelist is not empty. +	 * +	 * Since we still want to modify this buffer, we need to +	 * ensure that the buffer is not released on commit of +	 * the first transaction and ensure the buffer is added to the +	 * second transaction. +	 * +	 * If there is only one transaction then don't stop the buffer +	 * from being released when it commits later on. +	 */ + +	xfs_trans_bhold(tp, bp); + +	if ((error = xfs_bmap_finish(tpp, &flist, &committed))) { +		goto error1; +	} + +	if (committed) { +		tp = *tpp; +		xfs_trans_bjoin(tp, bp); +	} else { +		xfs_trans_bhold_release(tp, bp); +	} + +	*O_bpp = bp; +	return 0; + +      error1: +	xfs_bmap_cancel(&flist); +      error0: +	xfs_iunlock(quotip, XFS_ILOCK_EXCL); + +	return (error); +} + +STATIC int +xfs_qm_dqrepair( +	struct xfs_mount	*mp, +	struct xfs_trans	*tp, +	struct xfs_dquot	*dqp, +	xfs_dqid_t		firstid, +	struct xfs_buf		**bpp) +{ +	int			error; +	struct xfs_disk_dquot	*ddq; +	struct xfs_dqblk	*d; +	int			i; + +	/* +	 * Read the buffer without verification so we get the corrupted +	 * buffer returned to us. make sure we verify it on write, though. +	 */ +	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, dqp->q_blkno, +				   mp->m_quotainfo->qi_dqchunklen, +				   0, bpp, NULL); + +	if (error) { +		ASSERT(*bpp == NULL); +		return XFS_ERROR(error); +	} +	(*bpp)->b_ops = &xfs_dquot_buf_ops; + +	ASSERT(xfs_buf_islocked(*bpp)); +	d = (struct xfs_dqblk *)(*bpp)->b_addr; + +	/* Do the actual repair of dquots in this buffer */ +	for (i = 0; i < mp->m_quotainfo->qi_dqperchunk; i++) { +		ddq = &d[i].dd_diskdq; +		error = xfs_dqcheck(mp, ddq, firstid + i, +				       dqp->dq_flags & XFS_DQ_ALLTYPES, +				       XFS_QMOPT_DQREPAIR, "xfs_qm_dqrepair"); +		if (error) { +			/* repair failed, we're screwed */ +			xfs_trans_brelse(tp, *bpp); +			return XFS_ERROR(EIO); +		} +	} + +	return 0; +} + +/* + * Maps a dquot to the buffer containing its on-disk version. + * This returns a ptr to the buffer containing the on-disk dquot + * in the bpp param, and a ptr to the on-disk dquot within that buffer + */ +STATIC int +xfs_qm_dqtobp( +	xfs_trans_t		**tpp, +	xfs_dquot_t		*dqp, +	xfs_disk_dquot_t	**O_ddpp, +	xfs_buf_t		**O_bpp, +	uint			flags) +{ +	struct xfs_bmbt_irec	map; +	int			nmaps = 1, error; +	struct xfs_buf		*bp; +	struct xfs_inode	*quotip = xfs_dq_to_quota_inode(dqp); +	struct xfs_mount	*mp = dqp->q_mount; +	xfs_dqid_t		id = be32_to_cpu(dqp->q_core.d_id); +	struct xfs_trans	*tp = (tpp ? *tpp : NULL); +	uint			lock_mode; + +	dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk; + +	lock_mode = xfs_ilock_data_map_shared(quotip); +	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 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); + +	/* +	 * Offset of dquot in the (fixed sized) dquot chunk. +	 */ +	dqp->q_bufoffset = (id % mp->m_quotainfo->qi_dqperchunk) * +		sizeof(xfs_dqblk_t); + +	ASSERT(map.br_startblock != DELAYSTARTBLOCK); +	if (map.br_startblock == HOLESTARTBLOCK) { +		/* +		 * We don't allocate unless we're asked to +		 */ +		if (!(flags & XFS_QMOPT_DQALLOC)) +			return ENOENT; + +		ASSERT(tp); +		error = xfs_qm_dqalloc(tpp, mp, dqp, quotip, +					dqp->q_fileoffset, &bp); +		if (error) +			return error; +		tp = *tpp; +	} else { +		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, tp, mp->m_ddev_targp, +					   dqp->q_blkno, +					   mp->m_quotainfo->qi_dqchunklen, +					   0, &bp, &xfs_dquot_buf_ops); + +		if (error == EFSCORRUPTED && (flags & XFS_QMOPT_DQREPAIR)) { +			xfs_dqid_t firstid = (xfs_dqid_t)map.br_startoff * +						mp->m_quotainfo->qi_dqperchunk; +			ASSERT(bp == NULL); +			error = xfs_qm_dqrepair(mp, tp, dqp, firstid, &bp); +		} + +		if (error) { +			ASSERT(bp == NULL); +			return XFS_ERROR(error); +		} +	} + +	ASSERT(xfs_buf_islocked(bp)); +	*O_bpp = bp; +	*O_ddpp = bp->b_addr + dqp->q_bufoffset; + +	return (0); +} + + +/* + * Read in the ondisk dquot using dqtobp() then copy it to an incore version, + * and release the buffer immediately. + * + * If XFS_QMOPT_DQALLOC is set, allocate a dquot on disk if it needed. + */ +int +xfs_qm_dqread( +	struct xfs_mount	*mp, +	xfs_dqid_t		id, +	uint			type, +	uint			flags, +	struct xfs_dquot	**O_dqpp) +{ +	struct xfs_dquot	*dqp; +	struct xfs_disk_dquot	*ddqp; +	struct xfs_buf		*bp; +	struct xfs_trans	*tp = NULL; +	int			error; +	int			cancelflags = 0; + + +	dqp = kmem_zone_zalloc(xfs_qm_dqzone, KM_SLEEP); + +	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); + +	/* +	 * 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_STATS_INC(xs_qm_dquot); + +	trace_xfs_dqread(dqp); + +	if (flags & XFS_QMOPT_DQALLOC) { +		tp = xfs_trans_alloc(mp, XFS_TRANS_QM_DQALLOC); +		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_qm_dqalloc, +					  XFS_QM_DQALLOC_SPACE_RES(mp), 0); +		if (error) +			goto error1; +		cancelflags = XFS_TRANS_RELEASE_LOG_RES; +	} + +	/* +	 * get a pointer to the on-disk dquot and the buffer containing it +	 * dqp already knows its own type (GROUP/USER). +	 */ +	error = xfs_qm_dqtobp(&tp, dqp, &ddqp, &bp, flags); +	if (error) { +		/* +		 * This can happen if quotas got turned off (ESRCH), +		 * or if the dquot didn't exist on disk and we ask to +		 * allocate (ENOENT). +		 */ +		trace_xfs_dqread_fail(dqp); +		cancelflags |= XFS_TRANS_ABORT; +		goto error1; +	} + +	/* copy everything from disk dquot to the incore dquot */ +	memcpy(&dqp->q_core, ddqp, sizeof(xfs_disk_dquot_t)); +	xfs_qm_dquot_logitem_init(dqp); + +	/* +	 * 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); + +	/* Mark the buf so that this will stay incore a little longer */ +	xfs_buf_set_ref(bp, XFS_DQUOT_REF); + +	/* +	 * We got the buffer with a xfs_trans_read_buf() (in dqtobp()) +	 * So we need to release with xfs_trans_brelse(). +	 * The strategy here is identical to that of inodes; we lock +	 * the dquot in xfs_qm_dqget() before making it accessible to +	 * others. This is because dquots, like inodes, need a good level of +	 * concurrency, and we don't want to take locks on the entire buffers +	 * for dquot accesses. +	 * Note also that the dquot buffer may even be dirty at this point, if +	 * this particular dquot was repaired. We still aren't afraid to +	 * brelse it because we have the changes incore. +	 */ +	ASSERT(xfs_buf_islocked(bp)); +	xfs_trans_brelse(tp, bp); + +	if (tp) { +		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES); +		if (error) +			goto error0; +	} + +	*O_dqpp = dqp; +	return error; + +error1: +	if (tp) +		xfs_trans_cancel(tp, cancelflags); +error0: +	xfs_qm_dqdestroy(dqp); +	*O_dqpp = NULL; +	return error; +} + +/* + * Given the file system, inode OR id, and type (UDQUOT/GDQUOT), return a + * a locked dquot, doing an allocation (if requested) as needed. + * When both an inode and an id are given, the inode's id takes precedence. + * That is, if the id changes while we don't hold the ilock inside this + * function, the new dquot is returned, not necessarily the one requested + * in the id argument. + */ +int +xfs_qm_dqget( +	xfs_mount_t	*mp, +	xfs_inode_t	*ip,	  /* locked inode (optional) */ +	xfs_dqid_t	id,	  /* uid/projid/gid depending on type */ +	uint		type,	  /* XFS_DQ_USER/XFS_DQ_PROJ/XFS_DQ_GROUP */ +	uint		flags,	  /* DQALLOC, DQSUSER, DQREPAIR, DOWARN */ +	xfs_dquot_t	**O_dqpp) /* OUT : locked incore dquot */ +{ +	struct xfs_quotainfo	*qi = mp->m_quotainfo; +	struct radix_tree_root *tree = xfs_dquot_tree(qi, type); +	struct xfs_dquot	*dqp; +	int			error; + +	ASSERT(XFS_IS_QUOTA_RUNNING(mp)); +	if ((! XFS_IS_UQUOTA_ON(mp) && type == XFS_DQ_USER) || +	    (! XFS_IS_PQUOTA_ON(mp) && type == XFS_DQ_PROJ) || +	    (! XFS_IS_GQUOTA_ON(mp) && type == XFS_DQ_GROUP)) { +		return (ESRCH); +	} + +#ifdef DEBUG +	if (xfs_do_dqerror) { +		if ((xfs_dqerror_target == mp->m_ddev_targp) && +		    (xfs_dqreq_num++ % xfs_dqerror_mod) == 0) { +			xfs_debug(mp, "Returning error in dqget"); +			return (EIO); +		} +	} + +	ASSERT(type == XFS_DQ_USER || +	       type == XFS_DQ_PROJ || +	       type == XFS_DQ_GROUP); +	if (ip) { +		ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); +		ASSERT(xfs_inode_dquot(ip, type) == NULL); +	} +#endif + +restart: +	mutex_lock(&qi->qi_tree_lock); +	dqp = radix_tree_lookup(tree, id); +	if (dqp) { +		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(xs_qm_dqcachehits); +		*O_dqpp = dqp; +		return 0; +	} +	mutex_unlock(&qi->qi_tree_lock); +	XFS_STATS_INC(xs_qm_dqcachemisses); + +	/* +	 * 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. +	 */ +	if (ip) +		xfs_iunlock(ip, XFS_ILOCK_EXCL); + +	error = xfs_qm_dqread(mp, id, type, flags, &dqp); + +	if (ip) +		xfs_ilock(ip, XFS_ILOCK_EXCL); + +	if (error) +		return error; + +	if (ip) { +		/* +		 * 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 XFS_ERROR(ESRCH); +		} +	} + +	mutex_lock(&qi->qi_tree_lock); +	error = -radix_tree_insert(tree, id, dqp); +	if (unlikely(error)) { +		WARN_ON(error != EEXIST); + +		/* +		 * Duplicate found. Just throw away the new dquot and start +		 * over. +		 */ +		mutex_unlock(&qi->qi_tree_lock); +		trace_xfs_dqget_dup(dqp); +		xfs_qm_dqdestroy(dqp); +		XFS_STATS_INC(xs_qm_dquot_dups); +		goto restart; +	} + +	/* +	 * We 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); + + dqret: +	ASSERT((ip == NULL) || xfs_isilocked(ip, XFS_ILOCK_EXCL)); +	trace_xfs_dqget_miss(dqp); +	*O_dqpp = dqp; +	return (0); +} + +/* + * 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(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( +	xfs_dquot_t	*dqp) +{ +	if (!dqp) +		return; + +	trace_xfs_dqrele(dqp); + +	xfs_dqlock(dqp); +	/* +	 * We don't care to flush it if the dquot is dirty here. +	 * That will create stutters that we want to avoid. +	 * Instead we do a delayed write when we try to reclaim +	 * a dirty dquot. Also xfs_sync will take part of the burden... +	 */ +	xfs_qm_dqput(dqp); +} + +/* + * This is the dquot flushing I/O completion routine.  It is called + * from interrupt level when the buffer containing the dquot is + * flushed to disk.  It is responsible for removing the dquot logitem + * from the AIL if it has not been re-logged, and unlocking the dquot's + * flush lock. This behavior is very similar to that of inodes.. + */ +STATIC void +xfs_qm_dqflush_done( +	struct xfs_buf		*bp, +	struct xfs_log_item	*lip) +{ +	xfs_dq_logitem_t	*qip = (struct xfs_dq_logitem *)lip; +	xfs_dquot_t		*dqp = qip->qli_dquot; +	struct xfs_ail		*ailp = lip->li_ailp; + +	/* +	 * We only want to pull the item from the AIL if its +	 * location in the log has not changed since we started the flush. +	 * Thus, we only bother if the dquot's lsn has +	 * not changed. First we check the lsn outside the lock +	 * since it's cheaper, and then we recheck while +	 * holding the lock before removing the dquot from the AIL. +	 */ +	if ((lip->li_flags & XFS_LI_IN_AIL) && +	    lip->li_lsn == qip->qli_flush_lsn) { + +		/* xfs_trans_ail_delete() drops the AIL lock. */ +		spin_lock(&ailp->xa_lock); +		if (lip->li_lsn == qip->qli_flush_lsn) +			xfs_trans_ail_delete(ailp, lip, SHUTDOWN_CORRUPT_INCORE); +		else +			spin_unlock(&ailp->xa_lock); +	} + +	/* +	 * Release the dq's flush lock since we're done with it. +	 */ +	xfs_dqfunlock(dqp); +} + +/* + * Write a modified dquot to disk. + * The dquot must be locked and the flush lock too taken by caller. + * The flush lock will not be unlocked until the dquot reaches the disk, + * but the dquot is free to be unlocked and modified by the caller + * in the interim. Dquot is still locked on return. This behavior is + * identical to that of inodes. + */ +int +xfs_qm_dqflush( +	struct xfs_dquot	*dqp, +	struct xfs_buf		**bpp) +{ +	struct xfs_mount	*mp = dqp->q_mount; +	struct xfs_buf		*bp; +	struct xfs_disk_dquot	*ddqp; +	int			error; + +	ASSERT(XFS_DQ_IS_LOCKED(dqp)); +	ASSERT(!completion_done(&dqp->q_flush)); + +	trace_xfs_dqflush(dqp); + +	*bpp = NULL; + +	xfs_qm_dqunpin_wait(dqp); + +	/* +	 * This may have been unpinned because the filesystem is shutting +	 * down forcibly. If that's the case we must not write this dquot +	 * to disk, because the log record didn't make it to disk. +	 * +	 * We also have to remove the log item from the AIL in this case, +	 * as we wait for an emptry AIL as part of the unmount process. +	 */ +	if (XFS_FORCED_SHUTDOWN(mp)) { +		struct xfs_log_item	*lip = &dqp->q_logitem.qli_item; +		dqp->dq_flags &= ~XFS_DQ_DIRTY; + +		spin_lock(&mp->m_ail->xa_lock); +		if (lip->li_flags & XFS_LI_IN_AIL) +			xfs_trans_ail_delete(mp->m_ail, lip, +					     SHUTDOWN_CORRUPT_INCORE); +		else +			spin_unlock(&mp->m_ail->xa_lock); +		error = XFS_ERROR(EIO); +		goto out_unlock; +	} + +	/* +	 * Get the buffer containing the on-disk dquot +	 */ +	error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno, +				   mp->m_quotainfo->qi_dqchunklen, 0, &bp, NULL); +	if (error) +		goto out_unlock; + +	/* +	 * Calculate the location of the dquot inside the buffer. +	 */ +	ddqp = bp->b_addr + dqp->q_bufoffset; + +	/* +	 * A simple sanity check in case we got a corrupted dquot.. +	 */ +	error = xfs_dqcheck(mp, &dqp->q_core, be32_to_cpu(ddqp->d_id), 0, +			   XFS_QMOPT_DOWARN, "dqflush (incore copy)"); +	if (error) { +		xfs_buf_relse(bp); +		xfs_dqfunlock(dqp); +		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); +		return XFS_ERROR(EIO); +	} + +	/* This is the only portion of data that needs to persist */ +	memcpy(ddqp, &dqp->q_core, sizeof(xfs_disk_dquot_t)); + +	/* +	 * Clear the dirty field and remember the flush lsn for later use. +	 */ +	dqp->dq_flags &= ~XFS_DQ_DIRTY; + +	xfs_trans_ail_copy_lsn(mp->m_ail, &dqp->q_logitem.qli_flush_lsn, +					&dqp->q_logitem.qli_item.li_lsn); + +	/* +	 * copy the lsn into the on-disk dquot now while we have the in memory +	 * dquot here. This can't be done later in the write verifier as we +	 * can't get access to the log item at that point in time. +	 * +	 * We also calculate the CRC here so that the on-disk dquot in the +	 * buffer always has a valid CRC. This ensures there is no possibility +	 * of a dquot without an up-to-date CRC getting to disk. +	 */ +	if (xfs_sb_version_hascrc(&mp->m_sb)) { +		struct xfs_dqblk *dqb = (struct xfs_dqblk *)ddqp; + +		dqb->dd_lsn = cpu_to_be64(dqp->q_logitem.qli_item.li_lsn); +		xfs_update_cksum((char *)dqb, sizeof(struct xfs_dqblk), +				 XFS_DQUOT_CRC_OFF); +	} + +	/* +	 * Attach an iodone routine so that we can remove this dquot from the +	 * AIL and release the flush lock once the dquot is synced to disk. +	 */ +	xfs_buf_attach_iodone(bp, xfs_qm_dqflush_done, +				  &dqp->q_logitem.qli_item); + +	/* +	 * If the buffer is pinned then push on the log so we won't +	 * get stuck waiting in the write for too long. +	 */ +	if (xfs_buf_ispinned(bp)) { +		trace_xfs_dqflush_force(dqp); +		xfs_log_force(mp, 0); +	} + +	trace_xfs_dqflush_done(dqp); +	*bpp = bp; +	return 0; + +out_unlock: +	xfs_dqfunlock(dqp); +	return XFS_ERROR(EIO); +} + +/* + * Lock two xfs_dquot structures. + * + * To avoid deadlocks we always lock the quota structure with + * the lowerd id first. + */ +void +xfs_dqlock2( +	xfs_dquot_t	*d1, +	xfs_dquot_t	*d2) +{ +	if (d1 && d2) { +		ASSERT(d1 != d2); +		if (be32_to_cpu(d1->q_core.d_id) > +		    be32_to_cpu(d2->q_core.d_id)) { +			mutex_lock(&d2->q_qlock); +			mutex_lock_nested(&d1->q_qlock, XFS_QLOCK_NESTED); +		} else { +			mutex_lock(&d1->q_qlock); +			mutex_lock_nested(&d2->q_qlock, XFS_QLOCK_NESTED); +		} +	} else if (d1) { +		mutex_lock(&d1->q_qlock); +	} else if (d2) { +		mutex_lock(&d2->q_qlock); +	} +} + +int __init +xfs_qm_init(void) +{ +	xfs_qm_dqzone = +		kmem_zone_init(sizeof(struct xfs_dquot), "xfs_dquot"); +	if (!xfs_qm_dqzone) +		goto out; + +	xfs_qm_dqtrxzone = +		kmem_zone_init(sizeof(struct xfs_dquot_acct), "xfs_dqtrx"); +	if (!xfs_qm_dqtrxzone) +		goto out_free_dqzone; + +	return 0; + +out_free_dqzone: +	kmem_zone_destroy(xfs_qm_dqzone); +out: +	return -ENOMEM; +} + +void +xfs_qm_exit(void) +{ +	kmem_zone_destroy(xfs_qm_dqtrxzone); +	kmem_zone_destroy(xfs_qm_dqzone); +}  | 
