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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // 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_quota.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_trace.h"
 #include "xfs_log.h"
 #include "xfs_bmap_btree.h"
 #include "xfs_error.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_cache       *xfs_dqtrx_cache;
 static struct kmem_cache    *xfs_dquot_cache;
 
 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(
     struct xfs_dquot    *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_cache_free(xfs_dquot_cache, 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_dquot    *dq)
 {
     struct xfs_mount    *mp = dq->q_mount;
     struct xfs_quotainfo    *q = mp->m_quotainfo;
     struct xfs_def_quota    *defq;
     int         prealloc = 0;
 
     ASSERT(dq->q_id);
     defq = xfs_get_defquota(q, xfs_dquot_type(dq));
 
     if (!dq->q_blk.softlimit) {
         dq->q_blk.softlimit = defq->blk.soft;
         prealloc = 1;
     }
     if (!dq->q_blk.hardlimit) {
         dq->q_blk.hardlimit = defq->blk.hard;
         prealloc = 1;
     }
     if (!dq->q_ino.softlimit)
         dq->q_ino.softlimit = defq->ino.soft;
     if (!dq->q_ino.hardlimit)
         dq->q_ino.hardlimit = defq->ino.hard;
     if (!dq->q_rtb.softlimit)
         dq->q_rtb.softlimit = defq->rtb.soft;
     if (!dq->q_rtb.hardlimit)
         dq->q_rtb.hardlimit = defq->rtb.hard;
 
     if (prealloc)
         xfs_dquot_set_prealloc_limits(dq);
 }
 
 /* Set the expiration time of a quota's grace period. */
 time64_t
 xfs_dquot_set_timeout(
     struct xfs_mount    *mp,
     time64_t        timeout)
 {
     struct xfs_quotainfo    *qi = mp->m_quotainfo;
 
     return clamp_t(time64_t, timeout, qi->qi_expiry_min,
                       qi->qi_expiry_max);
 }
 
 /* Set the length of the default grace period. */
 time64_t
 xfs_dquot_set_grace_period(
     time64_t        grace)
 {
     return clamp_t(time64_t, grace, XFS_DQ_GRACE_MIN, XFS_DQ_GRACE_MAX);
 }
 
 /*
  * Determine if this quota counter is over either limit and set the quota
  * timers as appropriate.
  */
 static inline void
 xfs_qm_adjust_res_timer(
     struct xfs_mount    *mp,
     struct xfs_dquot_res    *res,
     struct xfs_quota_limits *qlim)
 {
     ASSERT(res->hardlimit == 0 || res->softlimit <= res->hardlimit);
 
     if ((res->softlimit && res->count > res->softlimit) ||
         (res->hardlimit && res->count > res->hardlimit)) {
         if (res->timer == 0)
             res->timer = xfs_dquot_set_timeout(mp,
                     ktime_get_real_seconds() + qlim->time);
     } else {
         res->timer = 0;
     }
 }
 
 /*
  * 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(
     struct xfs_dquot    *dq)
 {
     struct xfs_mount    *mp = dq->q_mount;
     struct xfs_quotainfo    *qi = mp->m_quotainfo;
     struct xfs_def_quota    *defq;
 
     ASSERT(dq->q_id);
     defq = xfs_get_defquota(qi, xfs_dquot_type(dq));
 
     xfs_qm_adjust_res_timer(dq->q_mount, &dq->q_blk, &defq->blk);
     xfs_qm_adjust_res_timer(dq->q_mount, &dq->q_ino, &defq->ino);
     xfs_qm_adjust_res_timer(dq->q_mount, &dq->q_rtb, &defq->rtb);
 }
 
 /*
  * initialize a buffer full of dquots and log the whole thing
  */
 STATIC void
 xfs_qm_init_dquot_blk(
     struct xfs_trans    *tp,
     struct xfs_mount    *mp,
     xfs_dqid_t      id,
     xfs_dqtype_t        type,
     struct xfs_buf      *bp)
 {
     struct xfs_quotainfo    *q = mp->m_quotainfo;
     struct xfs_dqblk    *d;
     xfs_dqid_t      curid;
     unsigned int        qflag;
     unsigned int        blftype;
     int         i;
 
     ASSERT(tp);
     ASSERT(xfs_buf_islocked(bp));
 
     switch (type) {
     case XFS_DQTYPE_USER:
         qflag = XFS_UQUOTA_CHKD;
         blftype = XFS_BLF_UDQUOT_BUF;
         break;
     case XFS_DQTYPE_PROJ:
         qflag = XFS_PQUOTA_CHKD;
         blftype = XFS_BLF_PDQUOT_BUF;
         break;
     case XFS_DQTYPE_GROUP:
         qflag = XFS_GQUOTA_CHKD;
         blftype = XFS_BLF_GDQUOT_BUF;
         break;
     default:
         ASSERT(0);
         return;
     }
 
     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_type = type;
         if (curid > 0 && xfs_has_bigtime(mp))
             d->dd_diskdq.d_type |= XFS_DQTYPE_BIGTIME;
         if (xfs_has_crc(mp)) {
             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, blftype);
 
     /*
      * quotacheck uses delayed writes to update all the dquots on disk in an
      * efficient manner instead of logging the individual dquot changes as
      * they are made. However if we log the buffer allocated here and crash
      * after quotacheck while the logged initialisation is still in the
      * active region of the log, log recovery can replay the dquot buffer
      * initialisation over the top of the checked dquots and corrupt quota
      * accounting.
      *
      * To avoid this problem, quotacheck cannot log the initialised buffer.
      * We must still dirty the buffer and write it back before the
      * allocation transaction clears the log. Therefore, mark the buffer as
      * ordered instead of logging it directly. This is safe for quotacheck
      * because it detects and repairs allocated but initialized dquot blocks
      * in the quota inodes.
      */
     if (!(mp->m_qflags & qflag))
         xfs_trans_ordered_buf(tp, bp);
     else
         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 = dqp->q_blk.hardlimit;
     dqp->q_prealloc_lo_wmark = dqp->q_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_dquot    *dqp,
     struct xfs_buf      **bpp)
 {
     struct xfs_bmbt_irec    map;
     struct xfs_trans    *tp;
     struct xfs_mount    *mp = dqp->q_mount;
     struct xfs_buf      *bp;
     xfs_dqtype_t        qtype = xfs_dquot_type(dqp);
     struct xfs_inode    *quotip = xfs_quota_inode(mp, qtype);
     int         nmaps = 1;
     int         error;
 
     trace_xfs_dqalloc(dqp);
 
     error = xfs_trans_alloc(mp, &M_RES(mp)->tr_qm_dqalloc,
             XFS_QM_DQALLOC_SPACE_RES(mp), 0, 0, &tp);
     if (error)
         return error;
 
     xfs_ilock(quotip, XFS_ILOCK_EXCL);
     xfs_trans_ijoin(tp, quotip, 0);
 
     if (!xfs_this_quota_on(dqp->q_mount, qtype)) {
         /*
          * Return if this type of quotas is turned off while we didn't
          * have an inode lock
          */
         error = -ESRCH;
         goto err_cancel;
     }
 
     error = xfs_iext_count_may_overflow(quotip, XFS_DATA_FORK,
             XFS_IEXT_ADD_NOSPLIT_CNT);
     if (error == -EFBIG)
         error = xfs_iext_count_upgrade(tp, quotip,
                 XFS_IEXT_ADD_NOSPLIT_CNT);
     if (error)
         goto err_cancel;
 
     /* Create the block mapping. */
     error = xfs_bmapi_write(tp, quotip, dqp->q_fileoffset,
             XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA, 0, &map,
             &nmaps);
     if (error)
         goto err_cancel;
 
     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) */
     error = xfs_trans_get_buf(tp, mp->m_ddev_targp, dqp->q_blkno,
             mp->m_quotainfo->qi_dqchunklen, 0, &bp);
     if (error)
         goto err_cancel;
     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, dqp->q_id, qtype, 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.
      *
      * Keep the quota inode ILOCKed until after the transaction commit to
      * maintain the atomicity of bmap/rmap updates.
      */
     xfs_trans_bhold(tp, bp);
     error = xfs_trans_commit(tp);
     xfs_iunlock(quotip, XFS_ILOCK_EXCL);
     if (error) {
         xfs_buf_relse(bp);
         return error;
     }
 
     *bpp = bp;
     return 0;
 
 err_cancel:
     xfs_trans_cancel(tp);
     xfs_iunlock(quotip, XFS_ILOCK_EXCL);
     return error;
 }
 
 /*
  * 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;
     xfs_dqtype_t        qtype = xfs_dquot_type(dqp);
     struct xfs_inode    *quotip = xfs_quota_inode(mp, qtype);
     uint            lock_mode;
     int         nmaps = 1;
     int         error;
 
     lock_mode = xfs_ilock_data_map_shared(quotip);
     if (!xfs_this_quota_on(mp, qtype)) {
         /*
          * 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,
     xfs_dqtype_t        type)
 {
     struct xfs_dquot    *dqp;
 
     dqp = kmem_cache_zalloc(xfs_dquot_cache, GFP_KERNEL | __GFP_NOFAIL);
 
     dqp->q_type = type;
     dqp->q_id = 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(struct xfs_dqblk);
 
     /*
      * 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_DQTYPE_USER:
         /* uses the default lock class */
         break;
     case XFS_DQTYPE_GROUP:
         lockdep_set_class(&dqp->q_qlock, &xfs_dquot_group_class);
         break;
     case XFS_DQTYPE_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;
 }
 
 /* Check the ondisk dquot's id and type match what the incore dquot expects. */
 static bool
 xfs_dquot_check_type(
     struct xfs_dquot    *dqp,
     struct xfs_disk_dquot   *ddqp)
 {
     uint8_t         ddqp_type;
     uint8_t         dqp_type;
 
     ddqp_type = ddqp->d_type & XFS_DQTYPE_REC_MASK;
     dqp_type = xfs_dquot_type(dqp);
 
     if (be32_to_cpu(ddqp->d_id) != dqp->q_id)
         return false;
 
     /*
      * V5 filesystems always expect an exact type match.  V4 filesystems
      * expect an exact match for user dquots and for non-root group and
      * project dquots.
      */
     if (xfs_has_crc(dqp->q_mount) ||
         dqp_type == XFS_DQTYPE_USER || dqp->q_id != 0)
         return ddqp_type == dqp_type;
 
     /*
      * V4 filesystems support either group or project quotas, but not both
      * at the same time.  The non-user quota file can be switched between
      * group and project quota uses depending on the mount options, which
      * means that we can encounter the other type when we try to load quota
      * defaults.  Quotacheck will soon reset the entire quota file
      * (including the root dquot) anyway, but don't log scary corruption
      * reports to dmesg.
      */
     return ddqp_type == XFS_DQTYPE_GROUP || ddqp_type == XFS_DQTYPE_PROJ;
 }
 
 /* Copy the in-core quota fields in from the on-disk buffer. */
 STATIC int
 xfs_dquot_from_disk(
     struct xfs_dquot    *dqp,
     struct xfs_buf      *bp)
 {
     struct xfs_disk_dquot   *ddqp = bp->b_addr + dqp->q_bufoffset;
 
     /*
      * Ensure that we got the type and ID we were looking for.
      * Everything else was checked by the dquot buffer verifier.
      */
     if (!xfs_dquot_check_type(dqp, ddqp)) {
         xfs_alert_tag(bp->b_mount, XFS_PTAG_VERIFIER_ERROR,
               "Metadata corruption detected at %pS, quota %u",
               __this_address, dqp->q_id);
         xfs_alert(bp->b_mount, "Unmount and run xfs_repair");
         return -EFSCORRUPTED;
     }
 
     /* copy everything from disk dquot to the incore dquot */
     dqp->q_type = ddqp->d_type;
     dqp->q_blk.hardlimit = be64_to_cpu(ddqp->d_blk_hardlimit);
     dqp->q_blk.softlimit = be64_to_cpu(ddqp->d_blk_softlimit);
     dqp->q_ino.hardlimit = be64_to_cpu(ddqp->d_ino_hardlimit);
     dqp->q_ino.softlimit = be64_to_cpu(ddqp->d_ino_softlimit);
     dqp->q_rtb.hardlimit = be64_to_cpu(ddqp->d_rtb_hardlimit);
     dqp->q_rtb.softlimit = be64_to_cpu(ddqp->d_rtb_softlimit);
 
     dqp->q_blk.count = be64_to_cpu(ddqp->d_bcount);
     dqp->q_ino.count = be64_to_cpu(ddqp->d_icount);
     dqp->q_rtb.count = be64_to_cpu(ddqp->d_rtbcount);
 
     dqp->q_blk.timer = xfs_dquot_from_disk_ts(ddqp, ddqp->d_btimer);
     dqp->q_ino.timer = xfs_dquot_from_disk_ts(ddqp, ddqp->d_itimer);
     dqp->q_rtb.timer = xfs_dquot_from_disk_ts(ddqp, ddqp->d_rtbtimer);
 
     /*
      * Reservation counters are defined as reservation plus current usage
      * to avoid having to add every time.
      */
     dqp->q_blk.reserved = dqp->q_blk.count;
     dqp->q_ino.reserved = dqp->q_ino.count;
     dqp->q_rtb.reserved = dqp->q_rtb.count;
 
     /* initialize the dquot speculative prealloc thresholds */
     xfs_dquot_set_prealloc_limits(dqp);
     return 0;
 }
 
 /* Copy the in-core quota fields into the on-disk buffer. */
 void
 xfs_dquot_to_disk(
     struct xfs_disk_dquot   *ddqp,
     struct xfs_dquot    *dqp)
 {
     ddqp->d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
     ddqp->d_version = XFS_DQUOT_VERSION;
     ddqp->d_type = dqp->q_type;
     ddqp->d_id = cpu_to_be32(dqp->q_id);
     ddqp->d_pad0 = 0;
     ddqp->d_pad = 0;
 
     ddqp->d_blk_hardlimit = cpu_to_be64(dqp->q_blk.hardlimit);
     ddqp->d_blk_softlimit = cpu_to_be64(dqp->q_blk.softlimit);
     ddqp->d_ino_hardlimit = cpu_to_be64(dqp->q_ino.hardlimit);
     ddqp->d_ino_softlimit = cpu_to_be64(dqp->q_ino.softlimit);
     ddqp->d_rtb_hardlimit = cpu_to_be64(dqp->q_rtb.hardlimit);
     ddqp->d_rtb_softlimit = cpu_to_be64(dqp->q_rtb.softlimit);
 
     ddqp->d_bcount = cpu_to_be64(dqp->q_blk.count);
     ddqp->d_icount = cpu_to_be64(dqp->q_ino.count);
     ddqp->d_rtbcount = cpu_to_be64(dqp->q_rtb.count);
 
     ddqp->d_bwarns = 0;
     ddqp->d_iwarns = 0;
     ddqp->d_rtbwarns = 0;
 
     ddqp->d_btimer = xfs_dquot_to_disk_ts(dqp, dqp->q_blk.timer);
     ddqp->d_itimer = xfs_dquot_to_disk_ts(dqp, dqp->q_ino.timer);
     ddqp->d_rtbtimer = xfs_dquot_to_disk_ts(dqp, dqp->q_rtb.timer);
 }
 
 /*
  * 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,
     xfs_dqtype_t        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_dquot_disk_alloc(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));
     error = xfs_dquot_from_disk(dqp, bp);
     xfs_buf_relse(bp);
     if (error)
         goto err;
 
     *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,
     xfs_dqtype_t        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);
     error = xfs_iread_extents(NULL, quotip, XFS_DATA_FORK);
     if (error)
         return error;
 
     if (xfs_iext_lookup_extent(quotip, &quotip->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->q_flags & XFS_DQFLAG_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,
     xfs_dqtype_t        type)
 {
     switch (type) {
     case XFS_DQTYPE_USER:
         if (!XFS_IS_UQUOTA_ON(mp))
             return -ESRCH;
         return 0;
     case XFS_DQTYPE_GROUP:
         if (!XFS_IS_GQUOTA_ON(mp))
             return -ESRCH;
         return 0;
     case XFS_DQTYPE_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/PDQUOT), return a
  * locked dquot, doing an allocation (if requested) as needed.
  */
 int
 xfs_qm_dqget(
     struct xfs_mount    *mp,
     xfs_dqid_t      id,
     xfs_dqtype_t        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,
     xfs_dqtype_t        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,
     xfs_dqtype_t        type)
 {
     switch (type) {
     case XFS_DQTYPE_USER:
         return i_uid_read(VFS_I(ip));
     case XFS_DQTYPE_GROUP:
         return i_gid_read(VFS_I(ip));
     case XFS_DQTYPE_PROJ:
         return ip->i_projid;
     }
     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,
     xfs_dqtype_t        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,
     xfs_dqtype_t        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(
     struct xfs_dquot    *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_log_item *lip)
 {
     struct xfs_dq_logitem   *qip = (struct xfs_dq_logitem *)lip;
     struct xfs_dquot    *dqp = qip->qli_dquot;
     struct xfs_ail      *ailp = lip->li_ailp;
     xfs_lsn_t       tail_lsn;
 
     /*
      * 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))) {
 
         spin_lock(&ailp->ail_lock);
         xfs_clear_li_failed(lip);
         if (lip->li_lsn == qip->qli_flush_lsn) {
             /* xfs_ail_update_finish() drops the AIL lock */
             tail_lsn = xfs_ail_delete_one(ailp, lip);
             xfs_ail_update_finish(ailp, tail_lsn);
         } else {
             spin_unlock(&ailp->ail_lock);
         }
     }
 
     /*
      * Release the dq's flush lock since we're done with it.
      */
     xfs_dqfunlock(dqp);
 }
 
 void
 xfs_buf_dquot_iodone(
     struct xfs_buf      *bp)
 {
     struct xfs_log_item *lip, *n;
 
     list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) {
         list_del_init(&lip->li_bio_list);
         xfs_qm_dqflush_done(lip);
     }
 }
 
 void
 xfs_buf_dquot_io_fail(
     struct xfs_buf      *bp)
 {
     struct xfs_log_item *lip;
 
     spin_lock(&bp->b_mount->m_ail->ail_lock);
     list_for_each_entry(lip, &bp->b_li_list, li_bio_list)
         xfs_set_li_failed(lip, bp);
     spin_unlock(&bp->b_mount->m_ail->ail_lock);
 }
 
 /* Check incore dquot for errors before we flush. */
 static xfs_failaddr_t
 xfs_qm_dqflush_check(
     struct xfs_dquot    *dqp)
 {
     xfs_dqtype_t        type = xfs_dquot_type(dqp);
 
     if (type != XFS_DQTYPE_USER &&
         type != XFS_DQTYPE_GROUP &&
         type != XFS_DQTYPE_PROJ)
         return __this_address;
 
     if (dqp->q_id == 0)
         return NULL;
 
     if (dqp->q_blk.softlimit && dqp->q_blk.count > dqp->q_blk.softlimit &&
         !dqp->q_blk.timer)
         return __this_address;
 
     if (dqp->q_ino.softlimit && dqp->q_ino.count > dqp->q_ino.softlimit &&
         !dqp->q_ino.timer)
         return __this_address;
 
     if (dqp->q_rtb.softlimit && dqp->q_rtb.count > dqp->q_rtb.softlimit &&
         !dqp->q_rtb.timer)
         return __this_address;
 
     /* bigtime flag should never be set on root dquots */
     if (dqp->q_type & XFS_DQTYPE_BIGTIME) {
         if (!xfs_has_bigtime(dqp->q_mount))
             return __this_address;
         if (dqp->q_id == 0)
             return __this_address;
     }
 
     return NULL;
 }
 
 /*
  * 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_log_item *lip = &dqp->q_logitem.qli_item;
     struct xfs_buf      *bp;
     struct xfs_dqblk    *dqblk;
     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);
 
     /*
      * 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, XBF_TRYLOCK,
                    &bp, &xfs_dquot_buf_ops);
     if (error == -EAGAIN)
         goto out_unlock;
     if (error)
         goto out_abort;
 
     fa = xfs_qm_dqflush_check(dqp);
     if (fa) {
         xfs_alert(mp, "corrupt dquot ID 0x%x in memory at %pS",
                 dqp->q_id, fa);
         xfs_buf_relse(bp);
         error = -EFSCORRUPTED;
         goto out_abort;
     }
 
     /* Flush the incore dquot to the ondisk buffer. */
     dqblk = bp->b_addr + dqp->q_bufoffset;
     xfs_dquot_to_disk(&dqblk->dd_diskdq, dqp);
 
     /*
      * Clear the dirty field and remember the flush lsn for later use.
      */
     dqp->q_flags &= ~XFS_DQFLAG_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_has_crc(mp)) {
         dqblk->dd_lsn = cpu_to_be64(dqp->q_logitem.qli_item.li_lsn);
         xfs_update_cksum((char *)dqblk, sizeof(struct xfs_dqblk),
                  XFS_DQUOT_CRC_OFF);
     }
 
     /*
      * Attach the dquot to the buffer so that we can remove this dquot from
      * the AIL and release the flush lock once the dquot is synced to disk.
      */
     bp->b_flags |= _XBF_DQUOTS;
     list_add_tail(&dqp->q_logitem.qli_item.li_bio_list, &bp->b_li_list);
 
     /*
      * 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_abort:
     dqp->q_flags &= ~XFS_DQFLAG_DIRTY;
     xfs_trans_ail_delete(lip, 0);
     xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
 out_unlock:
     xfs_dqfunlock(dqp);
     return error;
 }
 
 /*
  * Lock two xfs_dquot structures.
  *
  * To avoid deadlocks we always lock the quota structure with
  * the lowerd id first.
  */
 void
 xfs_dqlock2(
     struct xfs_dquot    *d1,
     struct xfs_dquot    *d2)
 {
     if (d1 && d2) {
         ASSERT(d1 != d2);
         if (d1->q_id > d2->q_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_dquot_cache = kmem_cache_create("xfs_dquot",
                       sizeof(struct xfs_dquot),
                       0, 0, NULL);
     if (!xfs_dquot_cache)
         goto out;
 
     xfs_dqtrx_cache = kmem_cache_create("xfs_dqtrx",
                          sizeof(struct xfs_dquot_acct),
                          0, 0, NULL);
     if (!xfs_dqtrx_cache)
         goto out_free_dquot_cache;
 
     return 0;
 
 out_free_dquot_cache:
     kmem_cache_destroy(xfs_dquot_cache);
 out:
     return -ENOMEM;
 }
 
 void
 xfs_qm_exit(void)
 {
     kmem_cache_destroy(xfs_dqtrx_cache);
     kmem_cache_destroy(xfs_dquot_cache);
 }
 
 /*
  * 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 -ECANCELED to indicate that it wants to stop iterating.
  */
 int
 xfs_qm_dqiterate(
     struct xfs_mount    *mp,
     xfs_dqtype_t        type,
     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, type, &dq);
         if (error == -ENOENT)
             return 0;
         if (error)
             return error;
 
         error = iter_fn(dq, type, priv);
         id = dq->q_id;
         xfs_qm_dqput(dq);
     } while (error == 0 && id != 0);
 
     return error;
 }

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