diff options
Diffstat (limited to 'fs/xfs/xfs_dquot.c')
-rw-r--r-- | fs/xfs/xfs_dquot.c | 1272 |
1 files changed, 1272 insertions, 0 deletions
diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c new file mode 100644 index 000000000..59b2b2954 --- /dev/null +++ b/fs/xfs/xfs_dquot.c @@ -0,0 +1,1272 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2000-2003 Silicon Graphics, Inc. + * All Rights Reserved. + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_shared.h" +#include "xfs_trans_resv.h" +#include "xfs_bit.h" +#include "xfs_mount.h" +#include "xfs_defer.h" +#include "xfs_inode.h" +#include "xfs_bmap.h" +#include "xfs_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. + */ + +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)); + + kmem_free(dqp->q_logitem.qli_item.li_lv_shadow); + mutex_destroy(&dqp->q_qlock); + + XFS_STATS_DEC(dqp->q_mount, xs_qm_dquot); + kmem_zone_free(xfs_qm_dqzone, dqp); +} + +/* + * If default limits are in force, push them into the dquot now. + * We overwrite the dquot limits only if they are zero and this + * is not the root dquot. + */ +void +xfs_qm_adjust_dqlimits( + struct xfs_mount *mp, + struct xfs_dquot *dq) +{ + struct xfs_quotainfo *q = mp->m_quotainfo; + struct xfs_disk_dquot *d = &dq->q_core; + struct xfs_def_quota *defq; + int prealloc = 0; + + ASSERT(d->d_id); + defq = xfs_get_defquota(dq, q); + + if (defq->bsoftlimit && !d->d_blk_softlimit) { + d->d_blk_softlimit = cpu_to_be64(defq->bsoftlimit); + prealloc = 1; + } + if (defq->bhardlimit && !d->d_blk_hardlimit) { + d->d_blk_hardlimit = cpu_to_be64(defq->bhardlimit); + prealloc = 1; + } + if (defq->isoftlimit && !d->d_ino_softlimit) + d->d_ino_softlimit = cpu_to_be64(defq->isoftlimit); + if (defq->ihardlimit && !d->d_ino_hardlimit) + d->d_ino_hardlimit = cpu_to_be64(defq->ihardlimit); + if (defq->rtbsoftlimit && !d->d_rtb_softlimit) + d->d_rtb_softlimit = cpu_to_be64(defq->rtbsoftlimit); + if (defq->rtbhardlimit && !d->d_rtb_hardlimit) + d->d_rtb_hardlimit = cpu_to_be64(defq->rtbhardlimit); + + if (prealloc) + xfs_dquot_set_prealloc_limits(dq); +} + +/* + * Check the limits and timers of a dquot and start or reset timers + * if necessary. + * This gets called even when quota enforcement is OFF, which makes our + * life a little less complicated. (We just don't reject any quota + * reservations in that case, when enforcement is off). + * We also return 0 as the values of the timers in Q_GETQUOTA calls, when + * enforcement's off. + * In contrast, warnings are a little different in that they don't + * 'automatically' get started when limits get exceeded. They do + * get reset to zero, however, when we find the count to be under + * the soft limit (they are only ever set non-zero via userspace). + */ +void +xfs_qm_adjust_dqtimers( + 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; + xfs_dqid_t curid; + int i; + + ASSERT(tp); + ASSERT(xfs_buf_islocked(bp)); + + d = bp->b_addr; + + /* + * ID of the first dquot in the block - id's are zero based. + */ + curid = id - (id % q->qi_dqperchunk); + memset(d, 0, BBTOB(q->qi_dqchunklen)); + for (i = 0; i < q->qi_dqperchunk; i++, d++, curid++) { + d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC); + d->dd_diskdq.d_version = XFS_DQUOT_VERSION; + d->dd_diskdq.d_id = cpu_to_be32(curid); + d->dd_diskdq.d_flags = type; + if (xfs_sb_version_hascrc(&mp->m_sb)) { + uuid_copy(&d->dd_uuid, &mp->m_sb.sb_meta_uuid); + xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk), + XFS_DQUOT_CRC_OFF); + } + } + + xfs_trans_dquot_buf(tp, bp, + (type & XFS_DQ_USER ? XFS_BLF_UDQUOT_BUF : + ((type & XFS_DQ_PROJ) ? XFS_BLF_PDQUOT_BUF : + XFS_BLF_GDQUOT_BUF))); + xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1); +} + +/* + * Initialize the dynamic speculative preallocation thresholds. The lo/hi + * watermarks correspond to the soft and hard limits by default. If a soft limit + * is not specified, we use 95% of the hard limit. + */ +void +xfs_dquot_set_prealloc_limits(struct xfs_dquot *dqp) +{ + uint64_t space; + + dqp->q_prealloc_hi_wmark = be64_to_cpu(dqp->q_core.d_blk_hardlimit); + dqp->q_prealloc_lo_wmark = be64_to_cpu(dqp->q_core.d_blk_softlimit); + if (!dqp->q_prealloc_lo_wmark) { + dqp->q_prealloc_lo_wmark = dqp->q_prealloc_hi_wmark; + do_div(dqp->q_prealloc_lo_wmark, 100); + dqp->q_prealloc_lo_wmark *= 95; + } + + space = dqp->q_prealloc_hi_wmark; + + do_div(space, 100); + dqp->q_low_space[XFS_QLOWSP_1_PCNT] = space; + dqp->q_low_space[XFS_QLOWSP_3_PCNT] = space * 3; + dqp->q_low_space[XFS_QLOWSP_5_PCNT] = space * 5; +} + +/* + * Ensure that the given in-core dquot has a buffer on disk backing it, and + * return the buffer locked and held. This is called when the bmapi finds a + * hole. + */ +STATIC int +xfs_dquot_disk_alloc( + struct xfs_trans **tpp, + struct xfs_dquot *dqp, + struct xfs_buf **bpp) +{ + struct xfs_bmbt_irec map; + struct xfs_trans *tp = *tpp; + struct xfs_mount *mp = tp->t_mountp; + struct xfs_buf *bp; + struct xfs_inode *quotip = xfs_quota_inode(mp, dqp->dq_flags); + int nmaps = 1; + int error; + + trace_xfs_dqalloc(dqp); + + xfs_ilock(quotip, XFS_ILOCK_EXCL); + if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) { + /* + * Return if this type of quotas is turned off while we didn't + * have an inode lock + */ + xfs_iunlock(quotip, XFS_ILOCK_EXCL); + return -ESRCH; + } + + /* Create the block mapping. */ + xfs_trans_ijoin(tp, quotip, XFS_ILOCK_EXCL); + error = xfs_bmapi_write(tp, quotip, dqp->q_fileoffset, + XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA, + XFS_QM_DQALLOC_SPACE_RES(mp), &map, &nmaps); + if (error) + return error; + ASSERT(map.br_blockcount == XFS_DQUOT_CLUSTER_SIZE_FSB); + ASSERT(nmaps == 1); + ASSERT((map.br_startblock != DELAYSTARTBLOCK) && + (map.br_startblock != HOLESTARTBLOCK)); + + /* + * Keep track of the blkno to save a lookup later + */ + dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock); + + /* now we can just get the buffer (there's nothing to read yet) */ + bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, dqp->q_blkno, + mp->m_quotainfo->qi_dqchunklen, 0); + if (!bp) + return -ENOMEM; + bp->b_ops = &xfs_dquot_buf_ops; + + /* + * Make a chunk of dquots out of this buffer and log + * the entire thing. + */ + xfs_qm_init_dquot_blk(tp, mp, be32_to_cpu(dqp->q_core.d_id), + dqp->dq_flags & XFS_DQ_ALLTYPES, bp); + xfs_buf_set_ref(bp, XFS_DQUOT_REF); + + /* + * Hold the buffer and join it to the dfops so that we'll still own + * the buffer when we return to the caller. The buffer disposal on + * error must be paid attention to very carefully, as it has been + * broken since commit efa092f3d4c6 "[XFS] Fixes a bug in the quota + * code when allocating a new dquot record" in 2005, and the later + * conversion to xfs_defer_ops in commit 310a75a3c6c747 failed to keep + * the buffer locked across the _defer_finish call. We can now do + * this correctly with xfs_defer_bjoin. + * + * Above, we allocated a disk block for the dquot information and used + * get_buf to initialize the dquot. If the _defer_finish fails, the old + * transaction is gone but the new buffer is not joined or held to any + * transaction, so we must _buf_relse it. + * + * If everything succeeds, the caller of this function is returned a + * buffer that is locked and held to the transaction. The caller + * is responsible for unlocking any buffer passed back, either + * manually or by committing the transaction. On error, the buffer is + * released and not passed back. + */ + xfs_trans_bhold(tp, bp); + error = xfs_defer_finish(tpp); + if (error) { + xfs_trans_bhold_release(*tpp, bp); + xfs_trans_brelse(*tpp, bp); + return error; + } + *bpp = bp; + return 0; +} + +/* + * Read in the in-core dquot's on-disk metadata and return the buffer. + * Returns ENOENT to signal a hole. + */ +STATIC int +xfs_dquot_disk_read( + struct xfs_mount *mp, + struct xfs_dquot *dqp, + struct xfs_buf **bpp) +{ + struct xfs_bmbt_irec map; + struct xfs_buf *bp; + struct xfs_inode *quotip = xfs_quota_inode(mp, dqp->dq_flags); + uint lock_mode; + int nmaps = 1; + int error; + + lock_mode = xfs_ilock_data_map_shared(quotip); + if (!xfs_this_quota_on(mp, dqp->dq_flags)) { + /* + * Return if this type of quotas is turned off while we + * didn't have the quota inode lock. + */ + xfs_iunlock(quotip, lock_mode); + return -ESRCH; + } + + /* + * Find the block map; no allocations yet + */ + error = xfs_bmapi_read(quotip, dqp->q_fileoffset, + XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0); + xfs_iunlock(quotip, lock_mode); + if (error) + return error; + + ASSERT(nmaps == 1); + ASSERT(map.br_blockcount >= 1); + ASSERT(map.br_startblock != DELAYSTARTBLOCK); + if (map.br_startblock == HOLESTARTBLOCK) + return -ENOENT; + + trace_xfs_dqtobp_read(dqp); + + /* + * store the blkno etc so that we don't have to do the + * mapping all the time + */ + dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock); + + error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno, + mp->m_quotainfo->qi_dqchunklen, 0, &bp, + &xfs_dquot_buf_ops); + if (error) { + ASSERT(bp == NULL); + return error; + } + + ASSERT(xfs_buf_islocked(bp)); + xfs_buf_set_ref(bp, XFS_DQUOT_REF); + *bpp = bp; + + return 0; +} + +/* Allocate and initialize everything we need for an incore dquot. */ +STATIC struct xfs_dquot * +xfs_dquot_alloc( + struct xfs_mount *mp, + xfs_dqid_t id, + uint type) +{ + struct xfs_dquot *dqp; + + dqp = kmem_zone_zalloc(xfs_qm_dqzone, 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); + dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk; + /* + * Offset of dquot in the (fixed sized) dquot chunk. + */ + dqp->q_bufoffset = (id % mp->m_quotainfo->qi_dqperchunk) * + sizeof(xfs_dqblk_t); + + /* + * Because we want to use a counting completion, complete + * the flush completion once to allow a single access to + * the flush completion without blocking. + */ + init_completion(&dqp->q_flush); + complete(&dqp->q_flush); + + /* + * Make sure group quotas have a different lock class than user + * quotas. + */ + switch (type) { + case XFS_DQ_USER: + /* uses the default lock class */ + break; + case XFS_DQ_GROUP: + lockdep_set_class(&dqp->q_qlock, &xfs_dquot_group_class); + break; + case XFS_DQ_PROJ: + lockdep_set_class(&dqp->q_qlock, &xfs_dquot_project_class); + break; + default: + ASSERT(0); + break; + } + + xfs_qm_dquot_logitem_init(dqp); + + XFS_STATS_INC(mp, xs_qm_dquot); + return dqp; +} + +/* Copy the in-core quota fields in from the on-disk buffer. */ +STATIC void +xfs_dquot_from_disk( + struct xfs_dquot *dqp, + struct xfs_buf *bp) +{ + struct xfs_disk_dquot *ddqp = bp->b_addr + dqp->q_bufoffset; + + /* copy everything from disk dquot to the incore dquot */ + memcpy(&dqp->q_core, ddqp, sizeof(xfs_disk_dquot_t)); + + /* + * Reservation counters are defined as reservation plus current usage + * to avoid having to add every time. + */ + dqp->q_res_bcount = be64_to_cpu(ddqp->d_bcount); + dqp->q_res_icount = be64_to_cpu(ddqp->d_icount); + dqp->q_res_rtbcount = be64_to_cpu(ddqp->d_rtbcount); + + /* initialize the dquot speculative prealloc thresholds */ + xfs_dquot_set_prealloc_limits(dqp); +} + +/* Allocate and initialize the dquot buffer for this in-core dquot. */ +static int +xfs_qm_dqread_alloc( + struct xfs_mount *mp, + struct xfs_dquot *dqp, + struct xfs_buf **bpp) +{ + struct xfs_trans *tp; + int error; + + error = xfs_trans_alloc(mp, &M_RES(mp)->tr_qm_dqalloc, + XFS_QM_DQALLOC_SPACE_RES(mp), 0, 0, &tp); + if (error) + goto err; + + error = xfs_dquot_disk_alloc(&tp, dqp, bpp); + if (error) + goto err_cancel; + + error = xfs_trans_commit(tp); + if (error) { + /* + * Buffer was held to the transaction, so we have to unlock it + * manually here because we're not passing it back. + */ + xfs_buf_relse(*bpp); + *bpp = NULL; + goto err; + } + return 0; + +err_cancel: + xfs_trans_cancel(tp); +err: + return error; +} + +/* + * Read in the ondisk dquot using dqtobp() then copy it to an incore version, + * and release the buffer immediately. If @can_alloc is true, fill any + * holes in the on-disk metadata. + */ +static int +xfs_qm_dqread( + struct xfs_mount *mp, + xfs_dqid_t id, + uint type, + bool can_alloc, + struct xfs_dquot **dqpp) +{ + struct xfs_dquot *dqp; + struct xfs_buf *bp; + int error; + + dqp = xfs_dquot_alloc(mp, id, type); + trace_xfs_dqread(dqp); + + /* Try to read the buffer, allocating if necessary. */ + error = xfs_dquot_disk_read(mp, dqp, &bp); + if (error == -ENOENT && can_alloc) + error = xfs_qm_dqread_alloc(mp, dqp, &bp); + if (error) + goto err; + + /* + * At this point we should have a clean locked buffer. Copy the data + * to the incore dquot and release the buffer since the incore dquot + * has its own locking protocol so we needn't tie up the buffer any + * further. + */ + ASSERT(xfs_buf_islocked(bp)); + xfs_dquot_from_disk(dqp, bp); + + xfs_buf_relse(bp); + *dqpp = dqp; + return error; + +err: + trace_xfs_dqread_fail(dqp); + xfs_qm_dqdestroy(dqp); + *dqpp = NULL; + return error; +} + +/* + * Advance to the next id in the current chunk, or if at the + * end of the chunk, skip ahead to first id in next allocated chunk + * using the SEEK_DATA interface. + */ +static int +xfs_dq_get_next_id( + struct xfs_mount *mp, + uint type, + xfs_dqid_t *id) +{ + struct xfs_inode *quotip = xfs_quota_inode(mp, type); + xfs_dqid_t next_id = *id + 1; /* simple advance */ + uint lock_flags; + struct xfs_bmbt_irec got; + struct xfs_iext_cursor cur; + xfs_fsblock_t start; + int error = 0; + + /* If we'd wrap past the max ID, stop */ + if (next_id < *id) + return -ENOENT; + + /* If new ID is within the current chunk, advancing it sufficed */ + if (next_id % mp->m_quotainfo->qi_dqperchunk) { + *id = next_id; + return 0; + } + + /* Nope, next_id is now past the current chunk, so find the next one */ + start = (xfs_fsblock_t)next_id / mp->m_quotainfo->qi_dqperchunk; + + lock_flags = xfs_ilock_data_map_shared(quotip); + if (!(quotip->i_df.if_flags & XFS_IFEXTENTS)) { + error = xfs_iread_extents(NULL, quotip, XFS_DATA_FORK); + if (error) + return error; + } + + if (xfs_iext_lookup_extent(quotip, "ip->i_df, start, &cur, &got)) { + /* contiguous chunk, bump startoff for the id calculation */ + if (got.br_startoff < start) + got.br_startoff = start; + *id = got.br_startoff * mp->m_quotainfo->qi_dqperchunk; + } else { + error = -ENOENT; + } + + xfs_iunlock(quotip, lock_flags); + + return error; +} + +/* + * Look up the dquot in the in-core cache. If found, the dquot is returned + * locked and ready to go. + */ +static struct xfs_dquot * +xfs_qm_dqget_cache_lookup( + struct xfs_mount *mp, + struct xfs_quotainfo *qi, + struct radix_tree_root *tree, + xfs_dqid_t id) +{ + struct xfs_dquot *dqp; + +restart: + mutex_lock(&qi->qi_tree_lock); + dqp = radix_tree_lookup(tree, id); + if (!dqp) { + mutex_unlock(&qi->qi_tree_lock); + XFS_STATS_INC(mp, xs_qm_dqcachemisses); + return NULL; + } + + xfs_dqlock(dqp); + if (dqp->dq_flags & XFS_DQ_FREEING) { + xfs_dqunlock(dqp); + mutex_unlock(&qi->qi_tree_lock); + trace_xfs_dqget_freeing(dqp); + delay(1); + goto restart; + } + + dqp->q_nrefs++; + mutex_unlock(&qi->qi_tree_lock); + + trace_xfs_dqget_hit(dqp); + XFS_STATS_INC(mp, xs_qm_dqcachehits); + return dqp; +} + +/* + * Try to insert a new dquot into the in-core cache. If an error occurs the + * caller should throw away the dquot and start over. Otherwise, the dquot + * is returned locked (and held by the cache) as if there had been a cache + * hit. + */ +static int +xfs_qm_dqget_cache_insert( + struct xfs_mount *mp, + struct xfs_quotainfo *qi, + struct radix_tree_root *tree, + xfs_dqid_t id, + struct xfs_dquot *dqp) +{ + int error; + + mutex_lock(&qi->qi_tree_lock); + error = radix_tree_insert(tree, id, dqp); + if (unlikely(error)) { + /* Duplicate found! Caller must try again. */ + WARN_ON(error != -EEXIST); + mutex_unlock(&qi->qi_tree_lock); + trace_xfs_dqget_dup(dqp); + return error; + } + + /* Return a locked dquot to the caller, with a reference taken. */ + xfs_dqlock(dqp); + dqp->q_nrefs = 1; + + qi->qi_dquots++; + mutex_unlock(&qi->qi_tree_lock); + + return 0; +} + +/* Check our input parameters. */ +static int +xfs_qm_dqget_checks( + struct xfs_mount *mp, + uint type) +{ + if (WARN_ON_ONCE(!XFS_IS_QUOTA_RUNNING(mp))) + return -ESRCH; + + switch (type) { + case XFS_DQ_USER: + if (!XFS_IS_UQUOTA_ON(mp)) + return -ESRCH; + return 0; + case XFS_DQ_GROUP: + if (!XFS_IS_GQUOTA_ON(mp)) + return -ESRCH; + return 0; + case XFS_DQ_PROJ: + if (!XFS_IS_PQUOTA_ON(mp)) + return -ESRCH; + return 0; + default: + WARN_ON_ONCE(0); + return -EINVAL; + } +} + +/* + * Given the file system, id, and type (UDQUOT/GDQUOT), return a a locked + * dquot, doing an allocation (if requested) as needed. + */ +int +xfs_qm_dqget( + struct xfs_mount *mp, + xfs_dqid_t id, + uint type, + bool can_alloc, + struct xfs_dquot **O_dqpp) +{ + struct xfs_quotainfo *qi = mp->m_quotainfo; + struct radix_tree_root *tree = xfs_dquot_tree(qi, type); + struct xfs_dquot *dqp; + int error; + + error = xfs_qm_dqget_checks(mp, type); + if (error) + return error; + +restart: + dqp = xfs_qm_dqget_cache_lookup(mp, qi, tree, id); + if (dqp) { + *O_dqpp = dqp; + return 0; + } + + error = xfs_qm_dqread(mp, id, type, can_alloc, &dqp); + if (error) + return error; + + error = xfs_qm_dqget_cache_insert(mp, qi, tree, id, dqp); + if (error) { + /* + * Duplicate found. Just throw away the new dquot and start + * over. + */ + xfs_qm_dqdestroy(dqp); + XFS_STATS_INC(mp, xs_qm_dquot_dups); + goto restart; + } + + trace_xfs_dqget_miss(dqp); + *O_dqpp = dqp; + return 0; +} + +/* + * Given a dquot id and type, read and initialize a dquot from the on-disk + * metadata. This function is only for use during quota initialization so + * it ignores the dquot cache assuming that the dquot shrinker isn't set up. + * The caller is responsible for _qm_dqdestroy'ing the returned dquot. + */ +int +xfs_qm_dqget_uncached( + struct xfs_mount *mp, + xfs_dqid_t id, + uint type, + struct xfs_dquot **dqpp) +{ + int error; + + error = xfs_qm_dqget_checks(mp, type); + if (error) + return error; + + return xfs_qm_dqread(mp, id, type, 0, dqpp); +} + +/* Return the quota id for a given inode and type. */ +xfs_dqid_t +xfs_qm_id_for_quotatype( + struct xfs_inode *ip, + uint type) +{ + switch (type) { + case XFS_DQ_USER: + return ip->i_d.di_uid; + case XFS_DQ_GROUP: + return ip->i_d.di_gid; + case XFS_DQ_PROJ: + return xfs_get_projid(ip); + } + ASSERT(0); + return 0; +} + +/* + * Return the dquot for a given inode and type. If @can_alloc is true, then + * allocate blocks if needed. The inode's ILOCK must be held and it must not + * have already had an inode attached. + */ +int +xfs_qm_dqget_inode( + struct xfs_inode *ip, + uint type, + bool can_alloc, + struct xfs_dquot **O_dqpp) +{ + struct xfs_mount *mp = ip->i_mount; + struct xfs_quotainfo *qi = mp->m_quotainfo; + struct radix_tree_root *tree = xfs_dquot_tree(qi, type); + struct xfs_dquot *dqp; + xfs_dqid_t id; + int error; + + error = xfs_qm_dqget_checks(mp, type); + if (error) + return error; + + ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); + ASSERT(xfs_inode_dquot(ip, type) == NULL); + + id = xfs_qm_id_for_quotatype(ip, type); + +restart: + dqp = xfs_qm_dqget_cache_lookup(mp, qi, tree, id); + if (dqp) { + *O_dqpp = dqp; + return 0; + } + + /* + * Dquot cache miss. We don't want to keep the inode lock across + * a (potential) disk read. Also we don't want to deal with the lock + * ordering between quotainode and this inode. OTOH, dropping the inode + * lock here means dealing with a chown that can happen before + * we re-acquire the lock. + */ + xfs_iunlock(ip, XFS_ILOCK_EXCL); + error = xfs_qm_dqread(mp, id, type, can_alloc, &dqp); + xfs_ilock(ip, XFS_ILOCK_EXCL); + if (error) + return error; + + /* + * A dquot could be attached to this inode by now, since we had + * dropped the ilock. + */ + if (xfs_this_quota_on(mp, type)) { + struct xfs_dquot *dqp1; + + dqp1 = xfs_inode_dquot(ip, type); + if (dqp1) { + xfs_qm_dqdestroy(dqp); + dqp = dqp1; + xfs_dqlock(dqp); + goto dqret; + } + } else { + /* inode stays locked on return */ + xfs_qm_dqdestroy(dqp); + return -ESRCH; + } + + error = xfs_qm_dqget_cache_insert(mp, qi, tree, id, dqp); + if (error) { + /* + * Duplicate found. Just throw away the new dquot and start + * over. + */ + xfs_qm_dqdestroy(dqp); + XFS_STATS_INC(mp, xs_qm_dquot_dups); + goto restart; + } + +dqret: + ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); + trace_xfs_dqget_miss(dqp); + *O_dqpp = dqp; + return 0; +} + +/* + * Starting at @id and progressing upwards, look for an initialized incore + * dquot, lock it, and return it. + */ +int +xfs_qm_dqget_next( + struct xfs_mount *mp, + xfs_dqid_t id, + uint type, + struct xfs_dquot **dqpp) +{ + struct xfs_dquot *dqp; + int error = 0; + + *dqpp = NULL; + for (; !error; error = xfs_dq_get_next_id(mp, type, &id)) { + error = xfs_qm_dqget(mp, id, type, false, &dqp); + if (error == -ENOENT) + continue; + else if (error != 0) + break; + + if (!XFS_IS_DQUOT_UNINITIALIZED(dqp)) { + *dqpp = dqp; + return 0; + } + + xfs_qm_dqput(dqp); + } + + return error; +} + +/* + * Release a reference to the dquot (decrement ref-count) and unlock it. + * + * If there is a group quota attached to this dquot, carefully release that + * too without tripping over deadlocks'n'stuff. + */ +void +xfs_qm_dqput( + struct xfs_dquot *dqp) +{ + ASSERT(dqp->q_nrefs > 0); + ASSERT(XFS_DQ_IS_LOCKED(dqp)); + + trace_xfs_dqput(dqp); + + if (--dqp->q_nrefs == 0) { + struct xfs_quotainfo *qi = dqp->q_mount->m_quotainfo; + trace_xfs_dqput_free(dqp); + + if (list_lru_add(&qi->qi_lru, &dqp->q_lru)) + XFS_STATS_INC(dqp->q_mount, xs_qm_dquot_unused); + } + xfs_dqunlock(dqp); +} + +/* + * Release a dquot. Flush it if dirty, then dqput() it. + * dquot must not be locked. + */ +void +xfs_qm_dqrele( + 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 (test_bit(XFS_LI_IN_AIL, &lip->li_flags) && + ((lip->li_lsn == qip->qli_flush_lsn) || + test_bit(XFS_LI_FAILED, &lip->li_flags))) { + + /* xfs_trans_ail_delete() drops the AIL lock. */ + spin_lock(&ailp->ail_lock); + if (lip->li_lsn == qip->qli_flush_lsn) { + xfs_trans_ail_delete(ailp, lip, SHUTDOWN_CORRUPT_INCORE); + } else { + /* + * Clear the failed state since we are about to drop the + * flush lock + */ + xfs_clear_li_failed(lip); + spin_unlock(&ailp->ail_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_dqblk *dqb; + struct xfs_disk_dquot *ddqp; + xfs_failaddr_t fa; + 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; + + xfs_trans_ail_remove(lip, SHUTDOWN_CORRUPT_INCORE); + + 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, + &xfs_dquot_buf_ops); + if (error) + goto out_unlock; + + /* + * Calculate the location of the dquot inside the buffer. + */ + dqb = bp->b_addr + dqp->q_bufoffset; + ddqp = &dqb->dd_diskdq; + + /* sanity check the in-core structure before we flush */ + fa = xfs_dquot_verify(mp, &dqp->q_core, be32_to_cpu(dqp->q_core.d_id), + 0); + if (fa) { + xfs_alert(mp, "corrupt dquot ID 0x%x in memory at %pS", + be32_to_cpu(dqp->q_core.d_id), fa); + xfs_buf_relse(bp); + xfs_dqfunlock(dqp); + xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); + return -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)) { + 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 -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); +} + +/* + * Iterate every dquot of a particular type. The caller must ensure that the + * particular quota type is active. iter_fn can return negative error codes, + * or XFS_BTREE_QUERY_RANGE_ABORT to indicate that it wants to stop iterating. + */ +int +xfs_qm_dqiterate( + struct xfs_mount *mp, + uint dqtype, + xfs_qm_dqiterate_fn iter_fn, + void *priv) +{ + struct xfs_dquot *dq; + xfs_dqid_t id = 0; + int error; + + do { + error = xfs_qm_dqget_next(mp, id, dqtype, &dq); + if (error == -ENOENT) + return 0; + if (error) + return error; + + error = iter_fn(dq, dqtype, priv); + id = be32_to_cpu(dq->q_core.d_id); + xfs_qm_dqput(dq); + id++; + } while (error == 0 && id != 0); + + return error; +} |