Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
[pandora-kernel.git] / fs / quota / dquot.c
index 788b580..1ad8bf0 100644 (file)
@@ -82,7 +82,7 @@
 
 /*
  * There are three quota SMP locks. dq_list_lock protects all lists with quotas
- * and quota formats, dqstats structure containing statistics about the lists
+ * and quota formats.
  * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and
  * also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
  * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
@@ -132,7 +132,9 @@ static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock);
 __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock);
 EXPORT_SYMBOL(dq_data_lock);
 
+#if defined(CONFIG_QUOTA_DEBUG) || defined(CONFIG_PRINT_QUOTA_WARNING)
 static char *quotatypes[] = INITQFNAMES;
+#endif
 static struct quota_format_type *quota_formats;        /* List of registered formats */
 static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
 
@@ -226,6 +228,10 @@ static struct hlist_head *dquot_hash;
 
 struct dqstats dqstats;
 EXPORT_SYMBOL(dqstats);
+#ifdef CONFIG_SMP
+struct dqstats *dqstats_pcpu;
+EXPORT_SYMBOL(dqstats_pcpu);
+#endif
 
 static qsize_t inode_get_rsv_space(struct inode *inode);
 static void __dquot_initialize(struct inode *inode, int type);
@@ -273,7 +279,7 @@ static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb,
 static inline void put_dquot_last(struct dquot *dquot)
 {
        list_add_tail(&dquot->dq_free, &free_dquots);
-       dqstats.free_dquots++;
+       dqstats_inc(DQST_FREE_DQUOTS);
 }
 
 static inline void remove_free_dquot(struct dquot *dquot)
@@ -281,7 +287,7 @@ static inline void remove_free_dquot(struct dquot *dquot)
        if (list_empty(&dquot->dq_free))
                return;
        list_del_init(&dquot->dq_free);
-       dqstats.free_dquots--;
+       dqstats_dec(DQST_FREE_DQUOTS);
 }
 
 static inline void put_inuse(struct dquot *dquot)
@@ -289,12 +295,12 @@ static inline void put_inuse(struct dquot *dquot)
        /* We add to the back of inuse list so we don't have to restart
         * when traversing this list and we block */
        list_add_tail(&dquot->dq_inuse, &inuse_list);
-       dqstats.allocated_dquots++;
+       dqstats_inc(DQST_ALLOC_DQUOTS);
 }
 
 static inline void remove_inuse(struct dquot *dquot)
 {
-       dqstats.allocated_dquots--;
+       dqstats_dec(DQST_ALLOC_DQUOTS);
        list_del(&dquot->dq_inuse);
 }
 /*
@@ -317,14 +323,23 @@ static inline int mark_dquot_dirty(struct dquot *dquot)
        return dquot->dq_sb->dq_op->mark_dirty(dquot);
 }
 
+/* Mark dquot dirty in atomic manner, and return it's old dirty flag state */
 int dquot_mark_dquot_dirty(struct dquot *dquot)
 {
+       int ret = 1;
+
+       /* If quota is dirty already, we don't have to acquire dq_list_lock */
+       if (test_bit(DQ_MOD_B, &dquot->dq_flags))
+               return 1;
+
        spin_lock(&dq_list_lock);
-       if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags))
+       if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) {
                list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
                                info[dquot->dq_type].dqi_dirty_list);
+               ret = 0;
+       }
        spin_unlock(&dq_list_lock);
-       return 0;
+       return ret;
 }
 EXPORT_SYMBOL(dquot_mark_dquot_dirty);
 
@@ -550,8 +565,8 @@ int dquot_scan_active(struct super_block *sb,
                        continue;
                /* Now we have active dquot so we can just increase use count */
                atomic_inc(&dquot->dq_count);
-               dqstats.lookups++;
                spin_unlock(&dq_list_lock);
+               dqstats_inc(DQST_LOOKUPS);
                dqput(old_dquot);
                old_dquot = dquot;
                ret = fn(dquot, priv);
@@ -596,8 +611,8 @@ int vfs_quota_sync(struct super_block *sb, int type, int wait)
                         * holding reference so we can safely just increase
                         * use count */
                        atomic_inc(&dquot->dq_count);
-                       dqstats.lookups++;
                        spin_unlock(&dq_list_lock);
+                       dqstats_inc(DQST_LOOKUPS);
                        sb->dq_op->write_dquot(dquot);
                        dqput(dquot);
                        spin_lock(&dq_list_lock);
@@ -609,9 +624,7 @@ int vfs_quota_sync(struct super_block *sb, int type, int wait)
                if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt)
                    && info_dirty(&dqopt->info[cnt]))
                        sb->dq_op->write_info(sb, cnt);
-       spin_lock(&dq_list_lock);
-       dqstats.syncs++;
-       spin_unlock(&dq_list_lock);
+       dqstats_inc(DQST_SYNCS);
        mutex_unlock(&dqopt->dqonoff_mutex);
 
        if (!wait || (sb_dqopt(sb)->flags & DQUOT_QUOTA_SYS_FILE))
@@ -663,6 +676,22 @@ static void prune_dqcache(int count)
        }
 }
 
+static int dqstats_read(unsigned int type)
+{
+       int count = 0;
+#ifdef CONFIG_SMP
+       int cpu;
+       for_each_possible_cpu(cpu)
+               count += per_cpu_ptr(dqstats_pcpu, cpu)->stat[type];
+       /* Statistics reading is racy, but absolute accuracy isn't required */
+       if (count < 0)
+               count = 0;
+#else
+       count = dqstats.stat[type];
+#endif
+       return count;
+}
+
 /*
  * This is called from kswapd when we think we need some
  * more memory
@@ -675,7 +704,7 @@ static int shrink_dqcache_memory(int nr, gfp_t gfp_mask)
                prune_dqcache(nr);
                spin_unlock(&dq_list_lock);
        }
-       return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure;
+       return (dqstats_read(DQST_FREE_DQUOTS)/100) * sysctl_vfs_cache_pressure;
 }
 
 static struct shrinker dqcache_shrinker = {
@@ -703,10 +732,7 @@ void dqput(struct dquot *dquot)
                BUG();
        }
 #endif
-       
-       spin_lock(&dq_list_lock);
-       dqstats.drops++;
-       spin_unlock(&dq_list_lock);
+       dqstats_inc(DQST_DROPS);
 we_slept:
        spin_lock(&dq_list_lock);
        if (atomic_read(&dquot->dq_count) > 1) {
@@ -823,15 +849,15 @@ we_slept:
                put_inuse(dquot);
                /* hash it first so it can be found */
                insert_dquot_hash(dquot);
-               dqstats.lookups++;
                spin_unlock(&dq_list_lock);
+               dqstats_inc(DQST_LOOKUPS);
        } else {
                if (!atomic_read(&dquot->dq_count))
                        remove_free_dquot(dquot);
                atomic_inc(&dquot->dq_count);
-               dqstats.cache_hits++;
-               dqstats.lookups++;
                spin_unlock(&dq_list_lock);
+               dqstats_inc(DQST_CACHE_HITS);
+               dqstats_inc(DQST_LOOKUPS);
        }
        /* Wait for dq_lock - after this we know that either dquot_release() is
         * already finished or it will be canceled due to dq_count > 1 test */
@@ -1488,11 +1514,13 @@ static void inode_decr_space(struct inode *inode, qsize_t number, int reserve)
 /*
  * This operation can block, but only after everything is updated
  */
-int __dquot_alloc_space(struct inode *inode, qsize_t number,
-               int warn, int reserve)
+int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags)
 {
        int cnt, ret = 0;
        char warntype[MAXQUOTAS];
+       int warn = flags & DQUOT_SPACE_WARN;
+       int reserve = flags & DQUOT_SPACE_RESERVE;
+       int nofail = flags & DQUOT_SPACE_NOFAIL;
 
        /*
         * First test before acquiring mutex - solves deadlocks when we
@@ -1513,7 +1541,7 @@ int __dquot_alloc_space(struct inode *inode, qsize_t number,
                        continue;
                ret = check_bdq(inode->i_dquot[cnt], number, !warn,
                                warntype+cnt);
-               if (ret) {
+               if (ret && !nofail) {
                        spin_unlock(&dq_data_lock);
                        goto out_flush_warn;
                }
@@ -1612,10 +1640,11 @@ EXPORT_SYMBOL(dquot_claim_space_nodirty);
 /*
  * This operation can block, but only after everything is updated
  */
-void __dquot_free_space(struct inode *inode, qsize_t number, int reserve)
+void __dquot_free_space(struct inode *inode, qsize_t number, int flags)
 {
        unsigned int cnt;
        char warntype[MAXQUOTAS];
+       int reserve = flags & DQUOT_SPACE_RESERVE;
 
        /* First test before acquiring mutex - solves deadlocks when we
          * re-enter the quota code and are already holding the mutex */
@@ -1677,16 +1706,19 @@ EXPORT_SYMBOL(dquot_free_inode);
 
 /*
  * Transfer the number of inode and blocks from one diskquota to an other.
+ * On success, dquot references in transfer_to are consumed and references
+ * to original dquots that need to be released are placed there. On failure,
+ * references are kept untouched.
  *
  * This operation can block, but only after everything is updated
  * A transaction must be started when entering this function.
+ *
  */
-static int __dquot_transfer(struct inode *inode, qid_t *chid, unsigned long mask)
+int __dquot_transfer(struct inode *inode, struct dquot **transfer_to)
 {
        qsize_t space, cur_space;
        qsize_t rsv_space = 0;
-       struct dquot *transfer_from[MAXQUOTAS];
-       struct dquot *transfer_to[MAXQUOTAS];
+       struct dquot *transfer_from[MAXQUOTAS] = {};
        int cnt, ret = 0;
        char warntype_to[MAXQUOTAS];
        char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS];
@@ -1696,19 +1728,12 @@ static int __dquot_transfer(struct inode *inode, qid_t *chid, unsigned long mask
        if (IS_NOQUOTA(inode))
                return 0;
        /* Initialize the arrays */
-       for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
-               transfer_from[cnt] = NULL;
-               transfer_to[cnt] = NULL;
+       for (cnt = 0; cnt < MAXQUOTAS; cnt++)
                warntype_to[cnt] = QUOTA_NL_NOWARN;
-       }
-       for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
-               if (mask & (1 << cnt))
-                       transfer_to[cnt] = dqget(inode->i_sb, chid[cnt], cnt);
-       }
        down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
        if (IS_NOQUOTA(inode)) {        /* File without quota accounting? */
                up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
-               goto put_all;
+               return 0;
        }
        spin_lock(&dq_data_lock);
        cur_space = inode_get_bytes(inode);
@@ -1760,47 +1785,41 @@ static int __dquot_transfer(struct inode *inode, qid_t *chid, unsigned long mask
 
        mark_all_dquot_dirty(transfer_from);
        mark_all_dquot_dirty(transfer_to);
-       /* The reference we got is transferred to the inode */
+       /* Pass back references to put */
        for (cnt = 0; cnt < MAXQUOTAS; cnt++)
-               transfer_to[cnt] = NULL;
-warn_put_all:
+               transfer_to[cnt] = transfer_from[cnt];
+warn:
        flush_warnings(transfer_to, warntype_to);
        flush_warnings(transfer_from, warntype_from_inodes);
        flush_warnings(transfer_from, warntype_from_space);
-put_all:
-       dqput_all(transfer_from);
-       dqput_all(transfer_to);
        return ret;
 over_quota:
        spin_unlock(&dq_data_lock);
        up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
-       /* Clear dquot pointers we don't want to dqput() */
-       for (cnt = 0; cnt < MAXQUOTAS; cnt++)
-               transfer_from[cnt] = NULL;
-       goto warn_put_all;
+       goto warn;
 }
+EXPORT_SYMBOL(__dquot_transfer);
 
 /* Wrapper for transferring ownership of an inode for uid/gid only
  * Called from FSXXX_setattr()
  */
 int dquot_transfer(struct inode *inode, struct iattr *iattr)
 {
-       qid_t chid[MAXQUOTAS];
-       unsigned long mask = 0;
+       struct dquot *transfer_to[MAXQUOTAS] = {};
+       struct super_block *sb = inode->i_sb;
+       int ret;
 
-       if (iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) {
-               mask |= 1 << USRQUOTA;
-               chid[USRQUOTA] = iattr->ia_uid;
-       }
-       if (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid) {
-               mask |= 1 << GRPQUOTA;
-               chid[GRPQUOTA] = iattr->ia_gid;
-       }
-       if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) {
-               dquot_initialize(inode);
-               return __dquot_transfer(inode, chid, mask);
-       }
-       return 0;
+       if (!sb_any_quota_active(sb) || IS_NOQUOTA(inode))
+               return 0;
+
+       if (iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid)
+               transfer_to[USRQUOTA] = dqget(sb, iattr->ia_uid, USRQUOTA);
+       if (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)
+               transfer_to[GRPQUOTA] = dqget(sb, iattr->ia_uid, GRPQUOTA);
+
+       ret = __dquot_transfer(inode, transfer_to);
+       dqput_all(transfer_to);
+       return ret;
 }
 EXPORT_SYMBOL(dquot_transfer);
 
@@ -2275,25 +2294,30 @@ static inline qsize_t stoqb(qsize_t space)
 }
 
 /* Generic routine for getting common part of quota structure */
-static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di)
+static void do_get_dqblk(struct dquot *dquot, struct fs_disk_quota *di)
 {
        struct mem_dqblk *dm = &dquot->dq_dqb;
 
+       memset(di, 0, sizeof(*di));
+       di->d_version = FS_DQUOT_VERSION;
+       di->d_flags = dquot->dq_type == USRQUOTA ?
+                       XFS_USER_QUOTA : XFS_GROUP_QUOTA;
+       di->d_id = dquot->dq_id;
+
        spin_lock(&dq_data_lock);
-       di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit);
-       di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit);
-       di->dqb_curspace = dm->dqb_curspace + dm->dqb_rsvspace;
-       di->dqb_ihardlimit = dm->dqb_ihardlimit;
-       di->dqb_isoftlimit = dm->dqb_isoftlimit;
-       di->dqb_curinodes = dm->dqb_curinodes;
-       di->dqb_btime = dm->dqb_btime;
-       di->dqb_itime = dm->dqb_itime;
-       di->dqb_valid = QIF_ALL;
+       di->d_blk_hardlimit = stoqb(dm->dqb_bhardlimit);
+       di->d_blk_softlimit = stoqb(dm->dqb_bsoftlimit);
+       di->d_ino_hardlimit = dm->dqb_ihardlimit;
+       di->d_ino_softlimit = dm->dqb_isoftlimit;
+       di->d_bcount = dm->dqb_curspace + dm->dqb_rsvspace;
+       di->d_icount = dm->dqb_curinodes;
+       di->d_btimer = dm->dqb_btime;
+       di->d_itimer = dm->dqb_itime;
        spin_unlock(&dq_data_lock);
 }
 
 int vfs_get_dqblk(struct super_block *sb, int type, qid_t id,
-                 struct if_dqblk *di)
+                 struct fs_disk_quota *di)
 {
        struct dquot *dquot;
 
@@ -2307,51 +2331,70 @@ int vfs_get_dqblk(struct super_block *sb, int type, qid_t id,
 }
 EXPORT_SYMBOL(vfs_get_dqblk);
 
+#define VFS_FS_DQ_MASK \
+       (FS_DQ_BCOUNT | FS_DQ_BSOFT | FS_DQ_BHARD | \
+        FS_DQ_ICOUNT | FS_DQ_ISOFT | FS_DQ_IHARD | \
+        FS_DQ_BTIMER | FS_DQ_ITIMER)
+
 /* Generic routine for setting common part of quota structure */
-static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
+static int do_set_dqblk(struct dquot *dquot, struct fs_disk_quota *di)
 {
        struct mem_dqblk *dm = &dquot->dq_dqb;
        int check_blim = 0, check_ilim = 0;
        struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
 
-       if ((di->dqb_valid & QIF_BLIMITS &&
-            (di->dqb_bhardlimit > dqi->dqi_maxblimit ||
-             di->dqb_bsoftlimit > dqi->dqi_maxblimit)) ||
-           (di->dqb_valid & QIF_ILIMITS &&
-            (di->dqb_ihardlimit > dqi->dqi_maxilimit ||
-             di->dqb_isoftlimit > dqi->dqi_maxilimit)))
+       if (di->d_fieldmask & ~VFS_FS_DQ_MASK)
+               return -EINVAL;
+
+       if (((di->d_fieldmask & FS_DQ_BSOFT) &&
+            (di->d_blk_softlimit > dqi->dqi_maxblimit)) ||
+           ((di->d_fieldmask & FS_DQ_BHARD) &&
+            (di->d_blk_hardlimit > dqi->dqi_maxblimit)) ||
+           ((di->d_fieldmask & FS_DQ_ISOFT) &&
+            (di->d_ino_softlimit > dqi->dqi_maxilimit)) ||
+           ((di->d_fieldmask & FS_DQ_IHARD) &&
+            (di->d_ino_hardlimit > dqi->dqi_maxilimit)))
                return -ERANGE;
 
        spin_lock(&dq_data_lock);
-       if (di->dqb_valid & QIF_SPACE) {
-               dm->dqb_curspace = di->dqb_curspace - dm->dqb_rsvspace;
+       if (di->d_fieldmask & FS_DQ_BCOUNT) {
+               dm->dqb_curspace = di->d_bcount - dm->dqb_rsvspace;
                check_blim = 1;
                set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
        }
-       if (di->dqb_valid & QIF_BLIMITS) {
-               dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit);
-               dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit);
+
+       if (di->d_fieldmask & FS_DQ_BSOFT)
+               dm->dqb_bsoftlimit = qbtos(di->d_blk_softlimit);
+       if (di->d_fieldmask & FS_DQ_BHARD)
+               dm->dqb_bhardlimit = qbtos(di->d_blk_hardlimit);
+       if (di->d_fieldmask & (FS_DQ_BSOFT | FS_DQ_BHARD)) {
                check_blim = 1;
                set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
        }
-       if (di->dqb_valid & QIF_INODES) {
-               dm->dqb_curinodes = di->dqb_curinodes;
+
+       if (di->d_fieldmask & FS_DQ_ICOUNT) {
+               dm->dqb_curinodes = di->d_icount;
                check_ilim = 1;
                set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
        }
-       if (di->dqb_valid & QIF_ILIMITS) {
-               dm->dqb_isoftlimit = di->dqb_isoftlimit;
-               dm->dqb_ihardlimit = di->dqb_ihardlimit;
+
+       if (di->d_fieldmask & FS_DQ_ISOFT)
+               dm->dqb_isoftlimit = di->d_ino_softlimit;
+       if (di->d_fieldmask & FS_DQ_IHARD)
+               dm->dqb_ihardlimit = di->d_ino_hardlimit;
+       if (di->d_fieldmask & (FS_DQ_ISOFT | FS_DQ_IHARD)) {
                check_ilim = 1;
                set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
        }
-       if (di->dqb_valid & QIF_BTIME) {
-               dm->dqb_btime = di->dqb_btime;
+
+       if (di->d_fieldmask & FS_DQ_BTIMER) {
+               dm->dqb_btime = di->d_btimer;
                check_blim = 1;
                set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
        }
-       if (di->dqb_valid & QIF_ITIME) {
-               dm->dqb_itime = di->dqb_itime;
+
+       if (di->d_fieldmask & FS_DQ_ITIMER) {
+               dm->dqb_itime = di->d_itimer;
                check_ilim = 1;
                set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
        }
@@ -2361,7 +2404,7 @@ static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
                    dm->dqb_curspace < dm->dqb_bsoftlimit) {
                        dm->dqb_btime = 0;
                        clear_bit(DQ_BLKS_B, &dquot->dq_flags);
-               } else if (!(di->dqb_valid & QIF_BTIME))
+               } else if (!(di->d_fieldmask & FS_DQ_BTIMER))
                        /* Set grace only if user hasn't provided his own... */
                        dm->dqb_btime = get_seconds() + dqi->dqi_bgrace;
        }
@@ -2370,7 +2413,7 @@ static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
                    dm->dqb_curinodes < dm->dqb_isoftlimit) {
                        dm->dqb_itime = 0;
                        clear_bit(DQ_INODES_B, &dquot->dq_flags);
-               } else if (!(di->dqb_valid & QIF_ITIME))
+               } else if (!(di->d_fieldmask & FS_DQ_ITIMER))
                        /* Set grace only if user hasn't provided his own... */
                        dm->dqb_itime = get_seconds() + dqi->dqi_igrace;
        }
@@ -2386,7 +2429,7 @@ static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
 }
 
 int vfs_set_dqblk(struct super_block *sb, int type, qid_t id,
-                 struct if_dqblk *di)
+                 struct fs_disk_quota *di)
 {
        struct dquot *dquot;
        int rc;
@@ -2465,62 +2508,74 @@ const struct quotactl_ops vfs_quotactl_ops = {
        .set_dqblk      = vfs_set_dqblk
 };
 
+
+static int do_proc_dqstats(struct ctl_table *table, int write,
+                    void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+#ifdef CONFIG_SMP
+       /* Update global table */
+       unsigned int type = (int *)table->data - dqstats.stat;
+       dqstats.stat[type] = dqstats_read(type);
+#endif
+       return proc_dointvec(table, write, buffer, lenp, ppos);
+}
+
 static ctl_table fs_dqstats_table[] = {
        {
                .procname       = "lookups",
-               .data           = &dqstats.lookups,
+               .data           = &dqstats.stat[DQST_LOOKUPS],
                .maxlen         = sizeof(int),
                .mode           = 0444,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = do_proc_dqstats,
        },
        {
                .procname       = "drops",
-               .data           = &dqstats.drops,
+               .data           = &dqstats.stat[DQST_DROPS],
                .maxlen         = sizeof(int),
                .mode           = 0444,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = do_proc_dqstats,
        },
        {
                .procname       = "reads",
-               .data           = &dqstats.reads,
+               .data           = &dqstats.stat[DQST_READS],
                .maxlen         = sizeof(int),
                .mode           = 0444,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = do_proc_dqstats,
        },
        {
                .procname       = "writes",
-               .data           = &dqstats.writes,
+               .data           = &dqstats.stat[DQST_WRITES],
                .maxlen         = sizeof(int),
                .mode           = 0444,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = do_proc_dqstats,
        },
        {
                .procname       = "cache_hits",
-               .data           = &dqstats.cache_hits,
+               .data           = &dqstats.stat[DQST_CACHE_HITS],
                .maxlen         = sizeof(int),
                .mode           = 0444,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = do_proc_dqstats,
        },
        {
                .procname       = "allocated_dquots",
-               .data           = &dqstats.allocated_dquots,
+               .data           = &dqstats.stat[DQST_ALLOC_DQUOTS],
                .maxlen         = sizeof(int),
                .mode           = 0444,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = do_proc_dqstats,
        },
        {
                .procname       = "free_dquots",
-               .data           = &dqstats.free_dquots,
+               .data           = &dqstats.stat[DQST_FREE_DQUOTS],
                .maxlen         = sizeof(int),
                .mode           = 0444,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = do_proc_dqstats,
        },
        {
                .procname       = "syncs",
-               .data           = &dqstats.syncs,
+               .data           = &dqstats.stat[DQST_SYNCS],
                .maxlen         = sizeof(int),
                .mode           = 0444,
-               .proc_handler   = proc_dointvec,
+               .proc_handler   = do_proc_dqstats,
        },
 #ifdef CONFIG_PRINT_QUOTA_WARNING
        {
@@ -2572,6 +2627,13 @@ static int __init dquot_init(void)
        if (!dquot_hash)
                panic("Cannot create dquot hash table");
 
+#ifdef CONFIG_SMP
+       dqstats_pcpu = alloc_percpu(struct dqstats);
+       if (!dqstats_pcpu)
+               panic("Cannot create dquot stats table");
+#endif
+       memset(&dqstats, 0, sizeof(struct dqstats));
+
        /* Find power-of-two hlist_heads which can fit into allocation */
        nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
        dq_hash_bits = 0;