diff options
Diffstat (limited to 'fs/xfs/xfs_dquot.c')
| -rw-r--r-- | fs/xfs/xfs_dquot.c | 1454 |
1 files changed, 1454 insertions, 0 deletions
diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c new file mode 100644 index 0000000..db62959 --- /dev/null +++ b/fs/xfs/xfs_dquot.c @@ -0,0 +1,1454 @@ +/* + * 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_bit.h" +#include "xfs_log.h" +#include "xfs_inum.h" +#include "xfs_trans.h" +#include "xfs_sb.h" +#include "xfs_ag.h" +#include "xfs_alloc.h" +#include "xfs_quota.h" +#include "xfs_mount.h" +#include "xfs_bmap_btree.h" +#include "xfs_inode.h" +#include "xfs_bmap.h" +#include "xfs_rtalloc.h" +#include "xfs_error.h" +#include "xfs_itable.h" +#include "xfs_attr.h" +#include "xfs_buf_item.h" +#include "xfs_trans_space.h" +#include "xfs_trans_priv.h" +#include "xfs_qm.h" +#include "xfs_trace.h" + + +/* + LOCK ORDER + + inode lock (ilock) + dquot hash-chain lock (hashlock) + xqm dquot freelist lock (freelistlock + mount's dquot list lock (mplistlock) + user dquot lock - lock ordering among dquots is based on the uid or gid + group dquot lock - similar to udquots. Between the two dquots, the udquot + has to be locked first. + pin lock - the dquot lock must be held to take this lock. + flush lock - ditto. +*/ + +#ifdef DEBUG +xfs_buftarg_t *xfs_dqerror_target; +int xfs_do_dqerror; +int xfs_dqreq_num; +int xfs_dqerror_mod = 33; +#endif + +static struct lock_class_key xfs_dquot_other_class; + +/* + * Allocate and initialize a dquot. We don't always allocate fresh memory; + * we try to reclaim a free dquot if the number of incore dquots are above + * a threshold. + * The only field inside the core that gets initialized at this point + * is the d_id field. The idea is to fill in the entire q_core + * when we read in the on disk dquot. + */ +STATIC xfs_dquot_t * +xfs_qm_dqinit( + xfs_mount_t *mp, + xfs_dqid_t id, + uint type) +{ + xfs_dquot_t *dqp; + boolean_t brandnewdquot; + + brandnewdquot = xfs_qm_dqalloc_incore(&dqp); + dqp->dq_flags = type; + dqp->q_core.d_id = cpu_to_be32(id); + dqp->q_mount = mp; + + /* + * No need to re-initialize these if this is a reclaimed dquot. + */ + if (brandnewdquot) { + INIT_LIST_HEAD(&dqp->q_freelist); + 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); + + trace_xfs_dqinit(dqp); + } else { + /* + * Only the q_core portion was zeroed in dqreclaim_one(). + * So, we need to reset others. + */ + dqp->q_nrefs = 0; + dqp->q_blkno = 0; + INIT_LIST_HEAD(&dqp->q_mplist); + INIT_LIST_HEAD(&dqp->q_hashlist); + dqp->q_bufoffset = 0; + dqp->q_fileoffset = 0; + dqp->q_transp = NULL; + dqp->q_gdquot = NULL; + dqp->q_res_bcount = 0; + dqp->q_res_icount = 0; + dqp->q_res_rtbcount = 0; + atomic_set(&dqp->q_pincount, 0); + dqp->q_hash = NULL; + ASSERT(list_empty(&dqp->q_freelist)); + + trace_xfs_dqreuse(dqp); + } + + /* + * In either case we need to make sure group quotas have a different + * lock class than user quotas, to make sure lockdep knows we can + * locks of one of each at the same time. + */ + if (!(type & XFS_DQ_USER)) + lockdep_set_class(&dqp->q_qlock, &xfs_dquot_other_class); + + /* + * log item gets initialized later + */ + return (dqp); +} + +/* + * 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_freelist)); + + mutex_destroy(&dqp->q_qlock); + kmem_zone_free(xfs_Gqm->qm_dqzone, dqp); + + atomic_dec(&xfs_Gqm->qm_totaldquots); +} + +/* + * This is what a 'fresh' dquot inside a dquot chunk looks like on disk. + */ +STATIC void +xfs_qm_dqinit_core( + xfs_dqid_t id, + uint type, + xfs_dqblk_t *d) +{ + /* + * Caller has zero'd the entire dquot 'chunk' already. + */ + 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(id); + d->dd_diskdq.d_flags = type; +} + +/* + * 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( + xfs_mount_t *mp, + xfs_disk_dquot_t *d) +{ + xfs_quotainfo_t *q = mp->m_quotainfo; + + ASSERT(d->d_id); + + if (q->qi_bsoftlimit && !d->d_blk_softlimit) + d->d_blk_softlimit = cpu_to_be64(q->qi_bsoftlimit); + if (q->qi_bhardlimit && !d->d_blk_hardlimit) + d->d_blk_hardlimit = cpu_to_be64(q->qi_bhardlimit); + 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); +} + +/* + * 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++) + xfs_qm_dqinit_core(curid, type, d); + 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); +} + + + +/* + * 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_IS_THIS_QUOTA_OFF(dqp)) { + xfs_iunlock(quotip, XFS_ILOCK_EXCL); + return (ESRCH); + } + + xfs_trans_ijoin_ref(tp, quotip, XFS_ILOCK_EXCL); + nmaps = 1; + if ((error = xfs_bmapi(tp, quotip, + offset_fsb, XFS_DQUOT_CLUSTER_SIZE_FSB, + XFS_BMAPI_METADATA | XFS_BMAPI_WRITE, + &firstblock, + XFS_QM_DQALLOC_SPACE_RES(mp), + &map, &nmaps, &flist))) { + 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 = xfs_buf_geterror(bp))) + goto error1; + /* + * 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); +} + +/* + * 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) +{ + xfs_bmbt_irec_t map; + int nmaps = 1, error; + xfs_buf_t *bp; + xfs_inode_t *quotip = XFS_DQ_TO_QIP(dqp); + xfs_mount_t *mp = dqp->q_mount; + xfs_disk_dquot_t *ddq; + xfs_dqid_t id = be32_to_cpu(dqp->q_core.d_id); + xfs_trans_t *tp = (tpp ? *tpp : NULL); + + dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk; + + xfs_ilock(quotip, XFS_ILOCK_SHARED); + if (XFS_IS_THIS_QUOTA_OFF(dqp)) { + /* + * Return if this type of quotas is turned off while we + * didn't have the quota inode lock. + */ + xfs_iunlock(quotip, XFS_ILOCK_SHARED); + return ESRCH; + } + + /* + * Find the block map; no allocations yet + */ + error = xfs_bmapi(NULL, quotip, dqp->q_fileoffset, + XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA, + NULL, 0, &map, &nmaps, NULL); + + xfs_iunlock(quotip, XFS_ILOCK_SHARED); + 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); + if (error || !bp) + return XFS_ERROR(error); + } + + ASSERT(xfs_buf_islocked(bp)); + + /* + * calculate the location of the dquot inside the buffer. + */ + ddq = bp->b_addr + dqp->q_bufoffset; + + /* + * A simple sanity check in case we got a corrupted dquot... + */ + error = xfs_qm_dqcheck(mp, ddq, id, dqp->dq_flags & XFS_DQ_ALLTYPES, + flags & (XFS_QMOPT_DQREPAIR|XFS_QMOPT_DOWARN), + "dqtobp"); + if (error) { + if (!(flags & XFS_QMOPT_DQREPAIR)) { + xfs_trans_brelse(tp, bp); + return XFS_ERROR(EIO); + } + } + + *O_bpp = bp; + *O_ddpp = ddq; + + return (0); +} + + +/* + * Read in the ondisk dquot using dqtobp() then copy it to an incore version, + * and release the buffer immediately. + * + */ +/* ARGSUSED */ +STATIC int +xfs_qm_dqread( + xfs_trans_t **tpp, + xfs_dqid_t id, + xfs_dquot_t *dqp, /* dquot to get filled in */ + uint flags) +{ + xfs_disk_dquot_t *ddqp; + xfs_buf_t *bp; + int error; + xfs_trans_t *tp; + + ASSERT(tpp); + + trace_xfs_dqread(dqp); + + /* + * get a pointer to the on-disk dquot and the buffer containing it + * dqp already knows its own type (GROUP/USER). + */ + if ((error = xfs_qm_dqtobp(tpp, dqp, &ddqp, &bp, flags))) { + return (error); + } + tp = *tpp; + + /* copy everything from disk dquot to the incore dquot */ + memcpy(&dqp->q_core, ddqp, sizeof(xfs_disk_dquot_t)); + ASSERT(be32_to_cpu(dqp->q_core.d_id) == id); + 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); + + /* Mark the buf so that this will stay incore a little longer */ + XFS_BUF_SET_VTYPE_REF(bp, B_FS_DQUOT, 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); + + return (error); +} + + +/* + * allocate an incore dquot from the kernel heap, + * and fill its core with quota information kept on disk. + * If XFS_QMOPT_DQALLOC is set, it'll allocate a dquot on disk + * if it wasn't already allocated. + */ +STATIC int +xfs_qm_idtodq( + xfs_mount_t *mp, + xfs_dqid_t id, /* gid or uid, depending on type */ + uint type, /* UDQUOT or GDQUOT */ + uint flags, /* DQALLOC, DQREPAIR */ + xfs_dquot_t **O_dqpp)/* OUT : incore dquot, not locked */ +{ + xfs_dquot_t *dqp; + int error; + xfs_trans_t *tp; + int cancelflags=0; + + dqp = xfs_qm_dqinit(mp, id, type); + tp = NULL; + if (flags & XFS_QMOPT_DQALLOC) { + tp = xfs_trans_alloc(mp, XFS_TRANS_QM_DQALLOC); + error = xfs_trans_reserve(tp, XFS_QM_DQALLOC_SPACE_RES(mp), + XFS_WRITE_LOG_RES(mp) + + BBTOB(mp->m_quotainfo->qi_dqchunklen) - 1 + + 128, + 0, + XFS_TRANS_PERM_LOG_RES, + XFS_WRITE_LOG_COUNT); + if (error) { + cancelflags = 0; + goto error0; + } + cancelflags = XFS_TRANS_RELEASE_LOG_RES; + } + + /* + * Read it from disk; xfs_dqread() takes care of + * all the necessary initialization of dquot's fields (locks, etc) + */ + if ((error = xfs_qm_dqread(&tp, id, dqp, flags))) { + /* + * 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 error0; + } + if (tp) { + if ((error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES))) + goto error1; + } + + *O_dqpp = dqp; + return (0); + + error0: + ASSERT(error); + if (tp) + xfs_trans_cancel(tp, cancelflags); + error1: + xfs_qm_dqdestroy(dqp); + *O_dqpp = NULL; + return (error); +} + +/* + * Lookup a dquot in the incore dquot hashtable. We keep two separate + * hashtables for user and group dquots; and, these are global tables + * inside the XQM, not per-filesystem tables. + * The hash chain must be locked by caller, and it is left locked + * on return. Returning dquot is locked. + */ +STATIC int +xfs_qm_dqlookup( + xfs_mount_t *mp, + xfs_dqid_t id, + xfs_dqhash_t *qh, + xfs_dquot_t **O_dqpp) +{ + xfs_dquot_t *dqp; + uint flist_locked; + + ASSERT(mutex_is_locked(&qh->qh_lock)); + + flist_locked = B_FALSE; + + /* + * Traverse the hashchain looking for a match + */ + list_for_each_entry(dqp, &qh->qh_list, q_hashlist) { + /* + * We already have the hashlock. We don't need the + * dqlock to look at the id field of the dquot, since the + * id can't be modified without the hashlock anyway. + */ + if (be32_to_cpu(dqp->q_core.d_id) == id && dqp->q_mount == mp) { + trace_xfs_dqlookup_found(dqp); + + /* + * All in core dquots must be on the dqlist of mp + */ + ASSERT(!list_empty(&dqp->q_mplist)); + + xfs_dqlock(dqp); + if (dqp->q_nrefs == 0) { + ASSERT(!list_empty(&dqp->q_freelist)); + if (!mutex_trylock(&xfs_Gqm->qm_dqfrlist_lock)) { + trace_xfs_dqlookup_want(dqp); + + /* + * We may have raced with dqreclaim_one() + * (and lost). So, flag that we don't + * want the dquot to be reclaimed. + */ + dqp->dq_flags |= XFS_DQ_WANT; + xfs_dqunlock(dqp); + mutex_lock(&xfs_Gqm->qm_dqfrlist_lock); + xfs_dqlock(dqp); + dqp->dq_flags &= ~(XFS_DQ_WANT); + } + flist_locked = B_TRUE; + } + + /* + * id couldn't have changed; we had the hashlock all + * along + */ + ASSERT(be32_to_cpu(dqp->q_core.d_id) == id); + + if (flist_locked) { + if (dqp->q_nrefs != 0) { + mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock); + flist_locked = B_FALSE; + } else { + /* take it off the freelist */ + trace_xfs_dqlookup_freelist(dqp); + list_del_init(&dqp->q_freelist); + xfs_Gqm->qm_dqfrlist_cnt--; + } + } + + XFS_DQHOLD(dqp); + + if (flist_locked) + mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock); + /* + * move the dquot to the front of the hashchain + */ + ASSERT(mutex_is_locked(&qh->qh_lock)); + list_move(&dqp->q_hashlist, &qh->qh_list); + trace_xfs_dqlookup_done(dqp); + *O_dqpp = dqp; + return 0; + } + } + + *O_dqpp = NULL; + ASSERT(mutex_is_locked(&qh->qh_lock)); + return (1); +} + +/* + * 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 */ +{ + xfs_dquot_t *dqp; + xfs_dqhash_t *h; + uint version; + 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); + } + h = XFS_DQ_HASH(mp, id, type); + +#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); + } + } +#endif + + again: + +#ifdef DEBUG + ASSERT(type == XFS_DQ_USER || + type == XFS_DQ_PROJ || + type == XFS_DQ_GROUP); + if (ip) { + ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); + if (type == XFS_DQ_USER) + ASSERT(ip->i_udquot == NULL); + else + ASSERT(ip->i_gdquot == NULL); + } +#endif + mutex_lock(&h->qh_lock); + + /* + * Look in the cache (hashtable). + * The chain is kept locked during lookup. + */ + if (xfs_qm_dqlookup(mp, id, h, O_dqpp) == 0) { + XQM_STATS_INC(xqmstats.xs_qm_dqcachehits); + /* + * The dquot was found, moved to the front of the chain, + * taken off the freelist if it was on it, and locked + * at this point. Just unlock the hashchain and return. + */ + ASSERT(*O_dqpp); + ASSERT(XFS_DQ_IS_LOCKED(*O_dqpp)); + mutex_unlock(&h->qh_lock); + trace_xfs_dqget_hit(*O_dqpp); + return (0); /* success */ + } + XQM_STATS_INC(xqmstats.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); + /* + * Save the hashchain version stamp, and unlock the chain, so that + * we don't keep the lock across a disk read + */ + version = h->qh_version; + mutex_unlock(&h->qh_lock); + + /* + * Allocate the dquot on the kernel heap, and read the ondisk + * portion off the disk. Also, do all the necessary initialization + * This can return ENOENT if dquot didn't exist on disk and we didn't + * ask it to allocate; ESRCH if quotas got turned off suddenly. + */ + if ((error = xfs_qm_idtodq(mp, id, type, + flags & (XFS_QMOPT_DQALLOC|XFS_QMOPT_DQREPAIR| + XFS_QMOPT_DOWARN), + &dqp))) { + if (ip) + xfs_ilock(ip, XFS_ILOCK_EXCL); + return (error); + } + + /* + * See if this is mount code calling to look at the overall quota limits + * which are stored in the id == 0 user or group's dquot. + * Since we may not have done a quotacheck by this point, just return + * the dquot without attaching it to any hashtables, lists, etc, or even + * taking a reference. + * The caller must dqdestroy this once done. + */ + if (flags & XFS_QMOPT_DQSUSER) { + ASSERT(id == 0); + ASSERT(! ip); + goto dqret; + } + + /* + * Dquot lock comes after hashlock in the lock ordering + */ + if (ip) { + xfs_ilock(ip, XFS_ILOCK_EXCL); + + /* + * A dquot could be attached to this inode by now, since + * we had dropped the ilock. + */ + if (type == XFS_DQ_USER) { + if (!XFS_IS_UQUOTA_ON(mp)) { + /* inode stays locked on return */ + xfs_qm_dqdestroy(dqp); + return XFS_ERROR(ESRCH); + } + if (ip->i_udquot) { + xfs_qm_dqdestroy(dqp); + dqp = ip->i_udquot; + xfs_dqlock(dqp); + goto dqret; + } + } else { + if (!XFS_IS_OQUOTA_ON(mp)) { + /* inode stays locked on return */ + xfs_qm_dqdestroy(dqp); + return XFS_ERROR(ESRCH); + } + if (ip->i_gdquot) { + xfs_qm_dqdestroy(dqp); + dqp = ip->i_gdquot; + xfs_dqlock(dqp); + goto dqret; + } + } + } + + /* + * Hashlock comes after ilock in lock order + */ + mutex_lock(&h->qh_lock); + if (version != h->qh_version) { + xfs_dquot_t *tmpdqp; + /* + * Now, see if somebody else put the dquot in the + * hashtable before us. This can happen because we didn't + * keep the hashchain lock. We don't have to worry about + * lock order between the two dquots here since dqp isn't + * on any findable lists yet. + */ + if (xfs_qm_dqlookup(mp, id, h, &tmpdqp) == 0) { + /* + * Duplicate found. Just throw away the new dquot + * and start over. + */ + xfs_qm_dqput(tmpdqp); + mutex_unlock(&h->qh_lock); + xfs_qm_dqdestroy(dqp); + XQM_STATS_INC(xqmstats.xs_qm_dquot_dups); + goto again; + } + } + + /* + * Put the dquot at the beginning of the hash-chain and mp's list + * LOCK ORDER: hashlock, freelistlock, mplistlock, udqlock, gdqlock .. + */ + ASSERT(mutex_is_locked(&h->qh_lock)); + dqp->q_hash = h; + list_add(&dqp->q_hashlist, &h->qh_list); + h->qh_version++; + + /* + * Attach this dquot to this filesystem's list of all dquots, + * kept inside the mount structure in m_quotainfo field + */ + mutex_lock(&mp->m_quotainfo->qi_dqlist_lock); + + /* + * We return a locked dquot to the caller, with a reference taken + */ + xfs_dqlock(dqp); + dqp->q_nrefs = 1; + + list_add(&dqp->q_mplist, &mp->m_quotainfo->qi_dqlist); + mp->m_quotainfo->qi_dquots++; + mutex_unlock(&mp->m_quotainfo->qi_dqlist_lock); + mutex_unlock(&h->qh_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( + xfs_dquot_t *dqp) +{ + xfs_dquot_t *gdqp; + + ASSERT(dqp->q_nrefs > 0); + ASSERT(XFS_DQ_IS_LOCKED(dqp)); + + trace_xfs_dqput(dqp); + + if (dqp->q_nrefs != 1) { + dqp->q_nrefs--; + xfs_dqunlock(dqp); + return; + } + + /* + * drop the dqlock and acquire the freelist and dqlock + * in the right order; but try to get it out-of-order first + */ + if (!mutex_trylock(&xfs_Gqm->qm_dqfrlist_lock)) { + trace_xfs_dqput_wait(dqp); + xfs_dqunlock(dqp); + mutex_lock(&xfs_Gqm->qm_dqfrlist_lock); + xfs_dqlock(dqp); + } + + while (1) { + gdqp = NULL; + + /* We can't depend on nrefs being == 1 here */ + if (--dqp->q_nrefs == 0) { + trace_xfs_dqput_free(dqp); + + list_add_tail(&dqp->q_freelist, &xfs_Gqm->qm_dqfrlist); + xfs_Gqm->qm_dqfrlist_cnt++; + + /* + * If we just added a udquot to the freelist, then + * we want to release the gdquot reference that + * it (probably) has. Otherwise it'll keep the + * gdquot from getting reclaimed. + */ + if ((gdqp = dqp->q_gdquot)) { + /* + * Avoid a recursive dqput call + */ + xfs_dqlock(gdqp); + dqp->q_gdquot = NULL; + } + } + xfs_dqunlock(dqp); + + /* + * If we had a group quota inside the user quota as a hint, + * release it now. + */ + if (! gdqp) + break; + dqp = gdqp; + } + mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock); +} + +/* + * 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); + 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( + xfs_dquot_t *dqp, + uint flags) +{ + 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); + + /* + * If not dirty, or it's pinned and we are not supposed to block, nada. + */ + if (!XFS_DQ_IS_DIRTY(dqp) || + (!(flags & SYNC_WAIT) && atomic_read(&dqp->q_pincount) > 0)) { + xfs_dqfunlock(dqp); + return 0; + } + 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! + */ + if (XFS_FORCED_SHUTDOWN(mp)) { + dqp->dq_flags &= ~XFS_DQ_DIRTY; + xfs_dqfunlock(dqp); + return XFS_ERROR(EIO); + } + + /* + * 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); + if (error) { + ASSERT(error != ENOENT); + xfs_dqfunlock(dqp); + return error; + } + + /* + * 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_qm_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); + + /* + * 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); + } + + if (flags & SYNC_WAIT) + error = xfs_bwrite(mp, bp); + else + xfs_bdwrite(mp, bp); + + trace_xfs_dqflush_done(dqp); + + /* + * dqp is still locked, but caller is free to unlock it now. + */ + return error; + +} + +int +xfs_qm_dqlock_nowait( + xfs_dquot_t *dqp) +{ + return mutex_trylock(&dqp->q_qlock); +} + +void +xfs_dqlock( + xfs_dquot_t *dqp) +{ + mutex_lock(&dqp->q_qlock); +} + +void +xfs_dqunlock( + xfs_dquot_t *dqp) +{ + mutex_unlock(&(dqp->q_qlock)); + if (dqp->q_logitem.qli_dquot == dqp) { + /* Once was dqp->q_mount, but might just have been cleared */ + xfs_trans_unlocked_item(dqp->q_logitem.qli_item.li_ailp, + (xfs_log_item_t*)&(dqp->q_logitem)); + } +} + + +void +xfs_dqunlock_nonotify( + xfs_dquot_t *dqp) +{ + mutex_unlock(&(dqp->q_qlock)); +} + +/* + * 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); + } +} + + +/* + * Take a dquot out of the mount's dqlist as well as the hashlist. + * This is called via unmount as well as quotaoff, and the purge + * will always succeed unless there are soft (temp) references + * outstanding. + * + * This returns 0 if it was purged, 1 if it wasn't. It's not an error code + * that we're returning! XXXsup - not cool. + */ +/* ARGSUSED */ +int +xfs_qm_dqpurge( + xfs_dquot_t *dqp) +{ + xfs_dqhash_t *qh = dqp->q_hash; + xfs_mount_t *mp = dqp->q_mount; + + ASSERT(mutex_is_locked(&mp->m_quotainfo->qi_dqlist_lock)); + ASSERT(mutex_is_locked(&dqp->q_hash->qh_lock)); + + xfs_dqlock(dqp); + /* + * We really can't afford to purge a dquot that is + * referenced, because these are hard refs. + * It shouldn't happen in general because we went thru _all_ inodes in + * dqrele_all_inodes before calling this and didn't let the mountlock go. + * However it is possible that we have dquots with temporary + * references that are not attached to an inode. e.g. see xfs_setattr(). + */ + if (dqp->q_nrefs != 0) { + xfs_dqunlock(dqp); + mutex_unlock(&dqp->q_hash->qh_lock); + return (1); + } + + ASSERT(!list_empty(&dqp->q_freelist)); + + /* + * If we're turning off quotas, we have to make sure that, for + * example, we don't delete quota disk blocks while dquots are + * in the process of getting written to those disk blocks. + * This dquot might well be on AIL, and we can't leave it there + * if we're turning off quotas. Basically, we need this flush + * lock, and are willing to block on it. + */ + if (!xfs_dqflock_nowait(dqp)) { + /* + * Block on the flush lock after nudging dquot buffer, + * if it is incore. + */ + xfs_qm_dqflock_pushbuf_wait(dqp); + } + + /* + * XXXIf we're turning this type of quotas off, we don't care + * about the dirty metadata sitting in this dquot. OTOH, if + * we're unmounting, we do care, so we flush it and wait. + */ + if (XFS_DQ_IS_DIRTY(dqp)) { + int error; + + /* dqflush unlocks dqflock */ + /* + * Given that dqpurge is a very rare occurrence, it is OK + * that we're holding the hashlist and mplist locks + * across the disk write. But, ... XXXsup + * + * We don't care about getting disk errors here. We need + * to purge this dquot anyway, so we go ahead regardless. + */ + error = xfs_qm_dqflush(dqp, SYNC_WAIT); + if (error) + xfs_warn(mp, "%s: dquot %p flush failed", + __func__, dqp); + xfs_dqflock(dqp); + } + ASSERT(atomic_read(&dqp->q_pincount) == 0); + ASSERT(XFS_FORCED_SHUTDOWN(mp) || + !(dqp->q_logitem.qli_item.li_flags & XFS_LI_IN_AIL)); + + list_del_init(&dqp->q_hashlist); + qh->qh_version++; + list_del_init(&dqp->q_mplist); + mp->m_quotainfo->qi_dqreclaims++; + mp->m_quotainfo->qi_dquots--; + /* + * XXX Move this to the front of the freelist, if we can get the + * freelist lock. + */ + ASSERT(!list_empty(&dqp->q_freelist)); + + dqp->q_mount = NULL; + dqp->q_hash = NULL; + dqp->dq_flags = XFS_DQ_INACTIVE; + memset(&dqp->q_core, 0, sizeof(dqp->q_core)); + xfs_dqfunlock(dqp); + xfs_dqunlock(dqp); + mutex_unlock(&qh->qh_lock); + return (0); +} + + +/* + * Give the buffer a little push if it is incore and + * wait on the flush lock. + */ +void +xfs_qm_dqflock_pushbuf_wait( + xfs_dquot_t *dqp) +{ + xfs_mount_t *mp = dqp->q_mount; + xfs_buf_t *bp; + + /* + * Check to see if the dquot has been flushed delayed + * write. If so, grab its buffer and send it + * out immediately. We'll be able to acquire + * the flush lock when the I/O completes. + */ + bp = xfs_incore(mp->m_ddev_targp, dqp->q_blkno, + mp->m_quotainfo->qi_dqchunklen, XBF_TRYLOCK); + if (!bp) + goto out_lock; + + if (XFS_BUF_ISDELAYWRITE(bp)) { + if (xfs_buf_ispinned(bp)) + xfs_log_force(mp, 0); + xfs_buf_delwri_promote(bp); + wake_up_process(bp->b_target->bt_task); + } + xfs_buf_relse(bp); +out_lock: + xfs_dqflock(dqp); +} |
