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From: Jan Kara <jack@suse.cz>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org, Jan Kara <jack@suse.cz>
Subject: [PATCH 02/14] quota: Increase size of variables for limits and inode usage
Date: Mon, 27 Oct 2008 13:11:40 +0100	[thread overview]
Message-ID: <12251095124166-git-send-email-jack@suse.cz> (raw)
In-Reply-To: <12251095123763-git-send-email-jack@suse.cz>

So far quota was fine with quota block limits and inode limits/numbers in
a 32-bit type. Now with rapid increase in storage sizes there are coming
requests to be able to handle quota limits above 4TB / more that 2^32 inodes.
So bump up sizes of types in mem_dqblk structure to 64-bits to be able to
handle this. Also update inode allocation / checking functions to use qsize_t
and make global structure keep quota limits in bytes so that things are
consistent.

Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/dquot.c               |   50 ++++++++++++++++++++++++++-------------------
 fs/quota_v1.c            |   25 +++++++++++++++++-----
 fs/quota_v2.c            |   21 +++++++++++++++---
 include/linux/quota.h    |   28 +++++++++++--------------
 include/linux/quotaops.h |    4 +-
 5 files changed, 79 insertions(+), 49 deletions(-)

diff --git a/fs/dquot.c b/fs/dquot.c
index e2ceb28..2e8b195 100644
--- a/fs/dquot.c
+++ b/fs/dquot.c
@@ -831,7 +831,7 @@ static void drop_dquot_ref(struct super_block *sb, int type)
 	}
 }
 
-static inline void dquot_incr_inodes(struct dquot *dquot, unsigned long number)
+static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number)
 {
 	dquot->dq_dqb.dqb_curinodes += number;
 }
@@ -841,7 +841,7 @@ static inline void dquot_incr_space(struct dquot *dquot, qsize_t number)
 	dquot->dq_dqb.dqb_curspace += number;
 }
 
-static inline void dquot_decr_inodes(struct dquot *dquot, unsigned long number)
+static inline void dquot_decr_inodes(struct dquot *dquot, qsize_t number)
 {
 	if (dquot->dq_dqb.dqb_curinodes > number)
 		dquot->dq_dqb.dqb_curinodes -= number;
@@ -858,7 +858,7 @@ static inline void dquot_decr_space(struct dquot *dquot, qsize_t number)
 		dquot->dq_dqb.dqb_curspace -= number;
 	else
 		dquot->dq_dqb.dqb_curspace = 0;
-	if (toqb(dquot->dq_dqb.dqb_curspace) <= dquot->dq_dqb.dqb_bsoftlimit)
+	if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
 		dquot->dq_dqb.dqb_btime = (time_t) 0;
 	clear_bit(DQ_BLKS_B, &dquot->dq_flags);
 }
@@ -1034,7 +1034,7 @@ static inline char ignore_hardlimit(struct dquot *dquot)
 }
 
 /* needs dq_data_lock */
-static int check_idq(struct dquot *dquot, ulong inodes, char *warntype)
+static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype)
 {
 	*warntype = QUOTA_NL_NOWARN;
 	if (inodes <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags))
@@ -1073,7 +1073,7 @@ static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *war
 		return QUOTA_OK;
 
 	if (dquot->dq_dqb.dqb_bhardlimit &&
-	   toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bhardlimit &&
+	    dquot->dq_dqb.dqb_curspace + space > dquot->dq_dqb.dqb_bhardlimit &&
             !ignore_hardlimit(dquot)) {
 		if (!prealloc)
 			*warntype = QUOTA_NL_BHARDWARN;
@@ -1081,7 +1081,7 @@ static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *war
 	}
 
 	if (dquot->dq_dqb.dqb_bsoftlimit &&
-	   toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit &&
+	    dquot->dq_dqb.dqb_curspace + space > dquot->dq_dqb.dqb_bsoftlimit &&
 	    dquot->dq_dqb.dqb_btime && get_seconds() >= dquot->dq_dqb.dqb_btime &&
             !ignore_hardlimit(dquot)) {
 		if (!prealloc)
@@ -1090,7 +1090,7 @@ static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *war
 	}
 
 	if (dquot->dq_dqb.dqb_bsoftlimit &&
-	   toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit &&
+	    dquot->dq_dqb.dqb_curspace + space > dquot->dq_dqb.dqb_bsoftlimit &&
 	    dquot->dq_dqb.dqb_btime == 0) {
 		if (!prealloc) {
 			*warntype = QUOTA_NL_BSOFTWARN;
@@ -1107,7 +1107,7 @@ static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *war
 	return QUOTA_OK;
 }
 
-static int info_idq_free(struct dquot *dquot, ulong inodes)
+static int info_idq_free(struct dquot *dquot, qsize_t inodes)
 {
 	if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
 	    dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit)
@@ -1124,15 +1124,13 @@ static int info_idq_free(struct dquot *dquot, ulong inodes)
 static int info_bdq_free(struct dquot *dquot, qsize_t space)
 {
 	if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
-	    toqb(dquot->dq_dqb.dqb_curspace) <= dquot->dq_dqb.dqb_bsoftlimit)
+	    dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
 		return QUOTA_NL_NOWARN;
 
-	if (toqb(dquot->dq_dqb.dqb_curspace - space) <=
-	    dquot->dq_dqb.dqb_bsoftlimit)
+	if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit)
 		return QUOTA_NL_BSOFTBELOW;
-	if (toqb(dquot->dq_dqb.dqb_curspace) >= dquot->dq_dqb.dqb_bhardlimit &&
-	    toqb(dquot->dq_dqb.dqb_curspace - space) <
-						dquot->dq_dqb.dqb_bhardlimit)
+	if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit &&
+	    dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit)
 		return QUOTA_NL_BHARDBELOW;
 	return QUOTA_NL_NOWARN;
 }
@@ -1275,7 +1273,7 @@ warn_put_all:
 /*
  * This operation can block, but only after everything is updated
  */
-int dquot_alloc_inode(const struct inode *inode, unsigned long number)
+int dquot_alloc_inode(const struct inode *inode, qsize_t number)
 {
 	int cnt, ret = NO_QUOTA;
 	char warntype[MAXQUOTAS];
@@ -1360,7 +1358,7 @@ out_sub:
 /*
  * This operation can block, but only after everything is updated
  */
-int dquot_free_inode(const struct inode *inode, unsigned long number)
+int dquot_free_inode(const struct inode *inode, qsize_t number)
 {
 	unsigned int cnt;
 	char warntype[MAXQUOTAS];
@@ -1877,14 +1875,24 @@ int vfs_dq_quota_on_remount(struct super_block *sb)
 	return ret;
 }
 
+static inline qsize_t qbtos(qsize_t blocks)
+{
+	return blocks << QIF_DQBLKSIZE_BITS;
+}
+
+static inline qsize_t stoqb(qsize_t space)
+{
+	return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
+}
+
 /* Generic routine for getting common part of quota structure */
 static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di)
 {
 	struct mem_dqblk *dm = &dquot->dq_dqb;
 
 	spin_lock(&dq_data_lock);
-	di->dqb_bhardlimit = dm->dqb_bhardlimit;
-	di->dqb_bsoftlimit = dm->dqb_bsoftlimit;
+	di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit);
+	di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit);
 	di->dqb_curspace = dm->dqb_curspace;
 	di->dqb_ihardlimit = dm->dqb_ihardlimit;
 	di->dqb_isoftlimit = dm->dqb_isoftlimit;
@@ -1931,8 +1939,8 @@ static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
 		check_blim = 1;
 	}
 	if (di->dqb_valid & QIF_BLIMITS) {
-		dm->dqb_bsoftlimit = di->dqb_bsoftlimit;
-		dm->dqb_bhardlimit = di->dqb_bhardlimit;
+		dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit);
+		dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit);
 		check_blim = 1;
 	}
 	if (di->dqb_valid & QIF_INODES) {
@@ -1950,7 +1958,7 @@ static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
 		dm->dqb_itime = di->dqb_itime;
 
 	if (check_blim) {
-		if (!dm->dqb_bsoftlimit || toqb(dm->dqb_curspace) < dm->dqb_bsoftlimit) {
+		if (!dm->dqb_bsoftlimit || dm->dqb_curspace < dm->dqb_bsoftlimit) {
 			dm->dqb_btime = 0;
 			clear_bit(DQ_BLKS_B, &dquot->dq_flags);
 		}
diff --git a/fs/quota_v1.c b/fs/quota_v1.c
index 5ae15b1..3e078ee 100644
--- a/fs/quota_v1.c
+++ b/fs/quota_v1.c
@@ -14,14 +14,27 @@ MODULE_AUTHOR("Jan Kara");
 MODULE_DESCRIPTION("Old quota format support");
 MODULE_LICENSE("GPL");
 
+#define QUOTABLOCK_BITS 10
+#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
+
+static inline qsize_t v1_stoqb(qsize_t space)
+{
+	return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
+}
+
+static inline qsize_t v1_qbtos(qsize_t blocks)
+{
+	return blocks << QUOTABLOCK_BITS;
+}
+
 static void v1_disk2mem_dqblk(struct mem_dqblk *m, struct v1_disk_dqblk *d)
 {
 	m->dqb_ihardlimit = d->dqb_ihardlimit;
 	m->dqb_isoftlimit = d->dqb_isoftlimit;
 	m->dqb_curinodes = d->dqb_curinodes;
-	m->dqb_bhardlimit = d->dqb_bhardlimit;
-	m->dqb_bsoftlimit = d->dqb_bsoftlimit;
-	m->dqb_curspace = ((qsize_t)d->dqb_curblocks) << QUOTABLOCK_BITS;
+	m->dqb_bhardlimit = v1_qbtos(d->dqb_bhardlimit);
+	m->dqb_bsoftlimit = v1_qbtos(d->dqb_bsoftlimit);
+	m->dqb_curspace = v1_qbtos(d->dqb_curblocks);
 	m->dqb_itime = d->dqb_itime;
 	m->dqb_btime = d->dqb_btime;
 }
@@ -31,9 +44,9 @@ static void v1_mem2disk_dqblk(struct v1_disk_dqblk *d, struct mem_dqblk *m)
 	d->dqb_ihardlimit = m->dqb_ihardlimit;
 	d->dqb_isoftlimit = m->dqb_isoftlimit;
 	d->dqb_curinodes = m->dqb_curinodes;
-	d->dqb_bhardlimit = m->dqb_bhardlimit;
-	d->dqb_bsoftlimit = m->dqb_bsoftlimit;
-	d->dqb_curblocks = toqb(m->dqb_curspace);
+	d->dqb_bhardlimit = v1_stoqb(m->dqb_bhardlimit);
+	d->dqb_bsoftlimit = v1_stoqb(m->dqb_bsoftlimit);
+	d->dqb_curblocks = v1_stoqb(m->dqb_curspace);
 	d->dqb_itime = m->dqb_itime;
 	d->dqb_btime = m->dqb_btime;
 }
diff --git a/fs/quota_v2.c b/fs/quota_v2.c
index b53827d..51c4717 100644
--- a/fs/quota_v2.c
+++ b/fs/quota_v2.c
@@ -26,6 +26,19 @@ typedef char *dqbuf_t;
 #define GETIDINDEX(id, depth) (((id) >> ((V2_DQTREEDEPTH-(depth)-1)*8)) & 0xff)
 #define GETENTRIES(buf) ((struct v2_disk_dqblk *)(((char *)buf)+sizeof(struct v2_disk_dqdbheader)))
 
+#define QUOTABLOCK_BITS 10
+#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
+
+static inline qsize_t v2_stoqb(qsize_t space)
+{
+	return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
+}
+
+static inline qsize_t v2_qbtos(qsize_t blocks)
+{
+	return blocks << QUOTABLOCK_BITS;
+}
+
 /* Check whether given file is really vfsv0 quotafile */
 static int v2_check_quota_file(struct super_block *sb, int type)
 {
@@ -104,8 +117,8 @@ static void disk2memdqb(struct mem_dqblk *m, struct v2_disk_dqblk *d)
 	m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
 	m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
 	m->dqb_itime = le64_to_cpu(d->dqb_itime);
-	m->dqb_bhardlimit = le32_to_cpu(d->dqb_bhardlimit);
-	m->dqb_bsoftlimit = le32_to_cpu(d->dqb_bsoftlimit);
+	m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
+	m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
 	m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
 	m->dqb_btime = le64_to_cpu(d->dqb_btime);
 }
@@ -116,8 +129,8 @@ static void mem2diskdqb(struct v2_disk_dqblk *d, struct mem_dqblk *m, qid_t id)
 	d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
 	d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
 	d->dqb_itime = cpu_to_le64(m->dqb_itime);
-	d->dqb_bhardlimit = cpu_to_le32(m->dqb_bhardlimit);
-	d->dqb_bsoftlimit = cpu_to_le32(m->dqb_bsoftlimit);
+	d->dqb_bhardlimit = cpu_to_le32(v2_qbtos(m->dqb_bhardlimit));
+	d->dqb_bsoftlimit = cpu_to_le32(v2_qbtos(m->dqb_bsoftlimit));
 	d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
 	d->dqb_btime = cpu_to_le64(m->dqb_btime);
 	d->dqb_id = cpu_to_le32(id);
diff --git a/include/linux/quota.h b/include/linux/quota.h
index a46df6d..1141133 100644
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -39,15 +39,6 @@
 #define __DQUOT_VERSION__	"dquot_6.5.1"
 #define __DQUOT_NUM_VERSION__	6*10000+5*100+1
 
-/* Size of blocks in which are counted size limits */
-#define QUOTABLOCK_BITS 10
-#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
-
-/* Conversion routines from and to quota blocks */
-#define qb2kb(x) ((x) << (QUOTABLOCK_BITS-10))
-#define kb2qb(x) ((x) >> (QUOTABLOCK_BITS-10))
-#define toqb(x) (((x) + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS)
-
 #define MAXQUOTAS 2
 #define USRQUOTA  0		/* element used for user quotas */
 #define GRPQUOTA  1		/* element used for group quotas */
@@ -80,6 +71,11 @@
 #define Q_GETQUOTA 0x800007	/* get user quota structure */
 #define Q_SETQUOTA 0x800008	/* set user quota structure */
 
+/* Size of block in which space limits are passed through the quota
+ * interface */
+#define QIF_DQBLKSIZE_BITS 10
+#define QIF_DQBLKSIZE (1 << QIF_DQBLKSIZE_BITS)
+
 /*
  * Quota structure used for communication with userspace via quotactl
  * Following flags are used to specify which fields are valid
@@ -187,12 +183,12 @@ extern spinlock_t dq_data_lock;
  * Data for one user/group kept in memory
  */
 struct mem_dqblk {
-	__u32 dqb_bhardlimit;	/* absolute limit on disk blks alloc */
-	__u32 dqb_bsoftlimit;	/* preferred limit on disk blks */
+	qsize_t dqb_bhardlimit;	/* absolute limit on disk blks alloc */
+	qsize_t dqb_bsoftlimit;	/* preferred limit on disk blks */
 	qsize_t dqb_curspace;	/* current used space */
-	__u32 dqb_ihardlimit;	/* absolute limit on allocated inodes */
-	__u32 dqb_isoftlimit;	/* preferred inode limit */
-	__u32 dqb_curinodes;	/* current # allocated inodes */
+	qsize_t dqb_ihardlimit;	/* absolute limit on allocated inodes */
+	qsize_t dqb_isoftlimit;	/* preferred inode limit */
+	qsize_t dqb_curinodes;	/* current # allocated inodes */
 	time_t dqb_btime;	/* time limit for excessive disk use */
 	time_t dqb_itime;	/* time limit for excessive inode use */
 };
@@ -287,9 +283,9 @@ struct dquot_operations {
 	int (*initialize) (struct inode *, int);
 	int (*drop) (struct inode *);
 	int (*alloc_space) (struct inode *, qsize_t, int);
-	int (*alloc_inode) (const struct inode *, unsigned long);
+	int (*alloc_inode) (const struct inode *, qsize_t);
 	int (*free_space) (struct inode *, qsize_t);
-	int (*free_inode) (const struct inode *, unsigned long);
+	int (*free_inode) (const struct inode *, qsize_t);
 	int (*transfer) (struct inode *, struct iattr *);
 	int (*write_dquot) (struct dquot *);		/* Ordinary dquot write */
 	struct dquot *(*alloc_dquot)(struct super_block *, int);	/* Allocate memory for new dquot (can be NULL if no special entries dquot are needed) */
diff --git a/include/linux/quotaops.h b/include/linux/quotaops.h
index a558a4c..adcc7ba 100644
--- a/include/linux/quotaops.h
+++ b/include/linux/quotaops.h
@@ -26,10 +26,10 @@ int dquot_initialize(struct inode *inode, int type);
 int dquot_drop(struct inode *inode);
 
 int dquot_alloc_space(struct inode *inode, qsize_t number, int prealloc);
-int dquot_alloc_inode(const struct inode *inode, unsigned long number);
+int dquot_alloc_inode(const struct inode *inode, qsize_t number);
 
 int dquot_free_space(struct inode *inode, qsize_t number);
-int dquot_free_inode(const struct inode *inode, unsigned long number);
+int dquot_free_inode(const struct inode *inode, qsize_t number);
 
 int dquot_transfer(struct inode *inode, struct iattr *iattr);
 int dquot_commit(struct dquot *dquot);
-- 
1.5.6


  reply	other threads:[~2008-10-27 12:11 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-10-27 12:11 [PATCH 00/14] 64-bit quotas and preparations for OCFS2 quotas Jan Kara
2008-10-27 12:11 ` [PATCH 01/14] quota: Add callbacks for allocating and destroying dquot structures Jan Kara
2008-10-27 12:11   ` Jan Kara [this message]
2008-10-27 12:11     ` [PATCH 03/14] quota: Remove bogus 'optimization' in check_idq() and check_bdq() Jan Kara
2008-10-27 12:11       ` [PATCH 04/14] quota: Make _SUSPENDED just a flag Jan Kara
2008-10-27 12:11         ` [PATCH 05/14] quota: Allow to separately enable quota accounting and enforcing limits Jan Kara
2008-10-27 12:11           ` [PATCH 06/14] ext3: Use sb_any_quota_loaded() instead of sb_any_quota_enabled() Jan Kara
2008-10-27 12:11             ` [PATCH 07/14] ext4: " Jan Kara
2008-10-27 12:11               ` [PATCH 08/14] reiserfs: " Jan Kara
2008-10-27 12:11                 ` [PATCH 09/14] quota: Remove compatibility function sb_any_quota_enabled() Jan Kara
2008-10-27 12:11                   ` [PATCH 10/14] quota: Introduce DQUOT_QUOTA_SYS_FILE flag Jan Kara
2008-10-27 12:11                     ` [PATCH 11/14] quota: Move quotaio_v[12].h from include/linux/ to fs/ Jan Kara
2008-10-27 12:11                       ` [PATCH 12/14] quota: Split off quota tree handling into a separate file Jan Kara
2008-10-27 12:11                         ` [PATCH 13/14] quota: Convert union in mem_dqinfo to a pointer Jan Kara
2008-10-27 12:11                           ` [PATCH 14/14] quota: Support 64-bit quota format Jan Kara
2008-10-28  5:29                             ` Andrew Morton
2008-10-29  2:39                               ` Jan Kara
2008-10-29  0:41                             ` Mingming Cao
2008-10-29  1:02                               ` Andrew Morton
2008-10-29 21:31                                 ` Mingming Cao
2008-10-28  5:55                           ` [PATCH 13/14] quota: Convert union in mem_dqinfo to a pointer Andrew Morton
2008-10-29  2:40                             ` Jan Kara
2008-10-28  5:52                         ` [PATCH 12/14] quota: Split off quota tree handling into a separate file Andrew Morton
2008-10-29  2:43                           ` Jan Kara
2008-10-28 22:32                       ` [PATCH 11/14] quota: Move quotaio_v[12].h from include/linux/ to fs/ Andrew Morton
2008-10-29  3:21                         ` Jan Kara
2008-10-28  5:44                     ` [PATCH 10/14] quota: Introduce DQUOT_QUOTA_SYS_FILE flag Andrew Morton
2008-10-28 17:51                       ` Joel Becker
2008-10-28  5:40     ` [PATCH 02/14] quota: Increase size of variables for limits and inode usage Andrew Morton
2008-10-28  9:11       ` Boaz Harrosh
2008-10-29  3:01       ` Jan Kara
2008-10-28  5:33   ` [PATCH 01/14] quota: Add callbacks for allocating and destroying dquot structures Andrew Morton
2008-10-29  3:05     ` Jan Kara

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