STATIC void xfs_qm_dqfree_one( struct xfs_dquot *dqp) { struct xfs_mount *mp = dqp->q_mount; struct xfs_quotainfo *qi = mp->m_quotainfo; mutex_lock(&qi->qi_tree_lock); radix_tree_delete(XFS_DQUOT_TREE(qi, dqp->q_core.d_flags), be32_to_cpu(dqp->q_core.d_id)); qi->qi_dquots--; mutex_unlock(&qi->qi_tree_lock); xfs_qm_dqdestroy(dqp); }
/* * 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; }
/* * 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; }
/* * This initializes all the quota information that's kept in the * mount structure */ STATIC int xfs_qm_init_quotainfo( xfs_mount_t *mp) { xfs_quotainfo_t *qinf; int error; xfs_dquot_t *dqp; ASSERT(XFS_IS_QUOTA_RUNNING(mp)); qinf = mp->m_quotainfo = kmem_zalloc(sizeof(xfs_quotainfo_t), KM_SLEEP); /* * See if quotainodes are setup, and if not, allocate them, * and change the superblock accordingly. */ if ((error = xfs_qm_init_quotainos(mp))) { kmem_free(qinf); mp->m_quotainfo = NULL; return error; } INIT_RADIX_TREE(&qinf->qi_uquota_tree, GFP_NOFS); INIT_RADIX_TREE(&qinf->qi_gquota_tree, GFP_NOFS); mutex_init(&qinf->qi_tree_lock); INIT_LIST_HEAD(&qinf->qi_lru_list); qinf->qi_lru_count = 0; mutex_init(&qinf->qi_lru_lock); /* mutex used to serialize quotaoffs */ mutex_init(&qinf->qi_quotaofflock); /* Precalc some constants */ qinf->qi_dqchunklen = XFS_FSB_TO_BB(mp, XFS_DQUOT_CLUSTER_SIZE_FSB); ASSERT(qinf->qi_dqchunklen); qinf->qi_dqperchunk = BBTOB(qinf->qi_dqchunklen); do_div(qinf->qi_dqperchunk, sizeof(xfs_dqblk_t)); mp->m_qflags |= (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_CHKD); /* * We try to get the limits from the superuser's limits fields. * This is quite hacky, but it is standard quota practice. * * We look at the USR dquot with id == 0 first, but if user quotas * are not enabled we goto the GRP dquot with id == 0. * We don't really care to keep separate default limits for user * and group quotas, at least not at this point. * * Since we may not have done a quotacheck by this point, just read * the dquot without attaching it to any hashtables or lists. */ error = xfs_qm_dqread(mp, 0, XFS_IS_UQUOTA_RUNNING(mp) ? XFS_DQ_USER : (XFS_IS_GQUOTA_RUNNING(mp) ? XFS_DQ_GROUP : XFS_DQ_PROJ), XFS_QMOPT_DOWARN, &dqp); if (!error) { xfs_disk_dquot_t *ddqp = &dqp->q_core; /* * The warnings and timers set the grace period given to * a user or group before he or she can not perform any * more writing. If it is zero, a default is used. */ qinf->qi_btimelimit = ddqp->d_btimer ? be32_to_cpu(ddqp->d_btimer) : XFS_QM_BTIMELIMIT; qinf->qi_itimelimit = ddqp->d_itimer ? be32_to_cpu(ddqp->d_itimer) : XFS_QM_ITIMELIMIT; qinf->qi_rtbtimelimit = ddqp->d_rtbtimer ? be32_to_cpu(ddqp->d_rtbtimer) : XFS_QM_RTBTIMELIMIT; qinf->qi_bwarnlimit = ddqp->d_bwarns ? be16_to_cpu(ddqp->d_bwarns) : XFS_QM_BWARNLIMIT; qinf->qi_iwarnlimit = ddqp->d_iwarns ? be16_to_cpu(ddqp->d_iwarns) : XFS_QM_IWARNLIMIT; qinf->qi_rtbwarnlimit = ddqp->d_rtbwarns ? be16_to_cpu(ddqp->d_rtbwarns) : XFS_QM_RTBWARNLIMIT; qinf->qi_bhardlimit = be64_to_cpu(ddqp->d_blk_hardlimit); qinf->qi_bsoftlimit = be64_to_cpu(ddqp->d_blk_softlimit); qinf->qi_ihardlimit = be64_to_cpu(ddqp->d_ino_hardlimit); qinf->qi_isoftlimit = be64_to_cpu(ddqp->d_ino_softlimit); qinf->qi_rtbhardlimit = be64_to_cpu(ddqp->d_rtb_hardlimit); qinf->qi_rtbsoftlimit = be64_to_cpu(ddqp->d_rtb_softlimit); xfs_qm_dqdestroy(dqp); } else { qinf->qi_btimelimit = XFS_QM_BTIMELIMIT; qinf->qi_itimelimit = XFS_QM_ITIMELIMIT; qinf->qi_rtbtimelimit = XFS_QM_RTBTIMELIMIT; qinf->qi_bwarnlimit = XFS_QM_BWARNLIMIT; qinf->qi_iwarnlimit = XFS_QM_IWARNLIMIT; qinf->qi_rtbwarnlimit = XFS_QM_RTBWARNLIMIT; } qinf->qi_shrinker.shrink = xfs_qm_shake; qinf->qi_shrinker.seeks = DEFAULT_SEEKS; register_shrinker(&qinf->qi_shrinker); return 0; }
/* * Purge a dquot from all tracking data structures and free it. */ STATIC int xfs_qm_dqpurge( struct xfs_dquot *dqp, void *data) { struct xfs_mount *mp = dqp->q_mount; struct xfs_quotainfo *qi = mp->m_quotainfo; struct xfs_dquot *gdqp = NULL; xfs_dqlock(dqp); if ((dqp->dq_flags & XFS_DQ_FREEING) || dqp->q_nrefs != 0) { xfs_dqunlock(dqp); return EAGAIN; } /* * If this quota has a group hint attached, prepare for releasing it * now. */ gdqp = dqp->q_gdquot; if (gdqp) { xfs_dqlock(gdqp); dqp->q_gdquot = NULL; } dqp->dq_flags |= XFS_DQ_FREEING; xfs_dqflock(dqp); /* * If we are 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)) { struct xfs_buf *bp = NULL; int error; /* * 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, &bp); if (error) { xfs_warn(mp, "%s: dquot %p flush failed", __func__, dqp); } else { error = xfs_bwrite(bp); xfs_buf_relse(bp); } 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)); xfs_dqfunlock(dqp); xfs_dqunlock(dqp); radix_tree_delete(XFS_DQUOT_TREE(qi, dqp->q_core.d_flags), be32_to_cpu(dqp->q_core.d_id)); qi->qi_dquots--; /* * We move dquots to the freelist as soon as their reference count * hits zero, so it really should be on the freelist here. */ mutex_lock(&qi->qi_lru_lock); ASSERT(!list_empty(&dqp->q_lru)); list_del_init(&dqp->q_lru); qi->qi_lru_count--; XFS_STATS_DEC(xs_qm_dquot_unused); mutex_unlock(&qi->qi_lru_lock); xfs_qm_dqdestroy(dqp); if (gdqp) xfs_qm_dqput(gdqp); return 0; }
/* * 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) { cmn_err(CE_DEBUG, "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_ISLOCKED_INODE_EXCL(ip)); if (type == XFS_DQ_USER) ASSERT(ip->i_udquot == NULL); else ASSERT(ip->i_gdquot == NULL); } #endif XFS_DQ_HASH_LOCK(h); /* * 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)); XFS_DQ_HASH_UNLOCK(h); xfs_dqtrace_entry(*O_dqpp, "DQGET DONE (FROM CACHE)"); 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; XFS_DQ_HASH_UNLOCK(h); /* * 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); if (! XFS_IS_DQTYPE_ON(mp, type)) { /* inode stays locked on return */ xfs_qm_dqdestroy(dqp); return XFS_ERROR(ESRCH); } /* * A dquot could be attached to this inode by now, since * we had dropped the ilock. */ if (type == XFS_DQ_USER) { if (ip->i_udquot) { xfs_qm_dqdestroy(dqp); dqp = ip->i_udquot; xfs_dqlock(dqp); goto dqret; } } else { if (ip->i_gdquot) { xfs_qm_dqdestroy(dqp); dqp = ip->i_gdquot; xfs_dqlock(dqp); goto dqret; } } } /* * Hashlock comes after ilock in lock order */ XFS_DQ_HASH_LOCK(h); 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); XFS_DQ_HASH_UNLOCK(h); 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(XFS_DQ_IS_HASH_LOCKED(h)); dqp->q_hash = h; XQM_HASHLIST_INSERT(h, dqp); /* * Attach this dquot to this filesystem's list of all dquots, * kept inside the mount structure in m_quotainfo field */ xfs_qm_mplist_lock(mp); /* * We return a locked dquot to the caller, with a reference taken */ xfs_dqlock(dqp); dqp->q_nrefs = 1; XQM_MPLIST_INSERT(&(XFS_QI_MPL_LIST(mp)), dqp); xfs_qm_mplist_unlock(mp); XFS_DQ_HASH_UNLOCK(h); dqret: ASSERT((ip == NULL) || XFS_ISLOCKED_INODE_EXCL(ip)); xfs_dqtrace_entry(dqp, "DQGET DONE"); *O_dqpp = dqp; return (0); }
/* * 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); if ((error = xfs_trans_reserve(tp, XFS_QM_DQALLOC_SPACE_RES(mp), XFS_WRITE_LOG_RES(mp) + BBTOB(XFS_QI_DQCHUNKLEN(mp)) - 1 + 128, 0, XFS_TRANS_PERM_LOG_RES, XFS_WRITE_LOG_COUNT))) { 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). */ xfs_dqtrace_entry(dqp, "DQREAD FAIL"); cancelflags |= XFS_TRANS_ABORT; goto error0; } if (tp) { if ((error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES, NULL))) 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); }
/* * 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); }
/* * 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; }
/* * 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; }