[linux-2.6-block.git] / fs / quota / quota_v1.c

#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/quota.h>
#include <linux/quotaops.h>
#include <linux/dqblk_v1.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>

#include <asm/byteorder.h>

#include "quotaio_v1.h"

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 = 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;
}

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 = 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;
}

static int v1_read_dqblk(struct dquot *dquot)
{
	int type = dquot->dq_id.type;
	struct v1_disk_dqblk dqblk;
	struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);

	if (!dqopt->files[type])
		return -EINVAL;

	/* Set structure to 0s in case read fails/is after end of file */
	memset(&dqblk, 0, sizeof(struct v1_disk_dqblk));
	dquot->dq_sb->s_op->quota_read(dquot->dq_sb, type, (char *)&dqblk,
			sizeof(struct v1_disk_dqblk),
			v1_dqoff(from_kqid(&init_user_ns, dquot->dq_id)));

	v1_disk2mem_dqblk(&dquot->dq_dqb, &dqblk);
	if (dquot->dq_dqb.dqb_bhardlimit == 0 &&
	    dquot->dq_dqb.dqb_bsoftlimit == 0 &&
	    dquot->dq_dqb.dqb_ihardlimit == 0 &&
	    dquot->dq_dqb.dqb_isoftlimit == 0)
		set_bit(DQ_FAKE_B, &dquot->dq_flags);
	dqstats_inc(DQST_READS);

	return 0;
}

static int v1_commit_dqblk(struct dquot *dquot)
{
	short type = dquot->dq_id.type;
	ssize_t ret;
	struct v1_disk_dqblk dqblk;

	v1_mem2disk_dqblk(&dqblk, &dquot->dq_dqb);
	if (((type == USRQUOTA) && uid_eq(dquot->dq_id.uid, GLOBAL_ROOT_UID)) ||
	    ((type == GRPQUOTA) && gid_eq(dquot->dq_id.gid, GLOBAL_ROOT_GID))) {
		dqblk.dqb_btime =
			sb_dqopt(dquot->dq_sb)->info[type].dqi_bgrace;
		dqblk.dqb_itime =
			sb_dqopt(dquot->dq_sb)->info[type].dqi_igrace;
	}
	ret = 0;
	if (sb_dqopt(dquot->dq_sb)->files[type])
		ret = dquot->dq_sb->s_op->quota_write(dquot->dq_sb, type,
			(char *)&dqblk, sizeof(struct v1_disk_dqblk),
			v1_dqoff(from_kqid(&init_user_ns, dquot->dq_id)));
	if (ret != sizeof(struct v1_disk_dqblk)) {
		quota_error(dquot->dq_sb, "dquota write failed");
		if (ret >= 0)
			ret = -EIO;
		goto out;
	}
	ret = 0;

out:
	dqstats_inc(DQST_WRITES);

	return ret;
}

/* Magics of new quota format */
#define V2_INITQMAGICS {\
	0xd9c01f11,     /* USRQUOTA */\
	0xd9c01927      /* GRPQUOTA */\
}

/* Header of new quota format */
struct v2_disk_dqheader {
	__le32 dqh_magic;        /* Magic number identifying file */
	__le32 dqh_version;      /* File version */
};

static int v1_check_quota_file(struct super_block *sb, int type)
{
	struct inode *inode = sb_dqopt(sb)->files[type];
	ulong blocks;
	size_t off; 
	struct v2_disk_dqheader dqhead;
	ssize_t size;
	loff_t isize;
	static const uint quota_magics[] = V2_INITQMAGICS;

	isize = i_size_read(inode);
	if (!isize)
		return 0;
	blocks = isize >> BLOCK_SIZE_BITS;
	off = isize & (BLOCK_SIZE - 1);
	if ((blocks % sizeof(struct v1_disk_dqblk) * BLOCK_SIZE + off) %
	    sizeof(struct v1_disk_dqblk))
		return 0;
	/* Doublecheck whether we didn't get file with new format - with old
	 * quotactl() this could happen */
	size = sb->s_op->quota_read(sb, type, (char *)&dqhead,
				    sizeof(struct v2_disk_dqheader), 0);
	if (size != sizeof(struct v2_disk_dqheader))
		return 1;	/* Probably not new format */
	if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type])
		return 1;	/* Definitely not new format */
	printk(KERN_INFO
	       "VFS: %s: Refusing to turn on old quota format on given file."
	       " It probably contains newer quota format.\n", sb->s_id);
        return 0;		/* Seems like a new format file -> refuse it */
}

static int v1_read_file_info(struct super_block *sb, int type)
{
	struct quota_info *dqopt = sb_dqopt(sb);
	struct v1_disk_dqblk dqblk;
	int ret;

	down_read(&dqopt->dqio_sem);
	ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
				sizeof(struct v1_disk_dqblk), v1_dqoff(0));
	if (ret != sizeof(struct v1_disk_dqblk)) {
		if (ret >= 0)
			ret = -EIO;
		goto out;
	}
	ret = 0;
	/* limits are stored as unsigned 32-bit data */
	dqopt->info[type].dqi_max_spc_limit = 0xffffffffULL << QUOTABLOCK_BITS;
	dqopt->info[type].dqi_max_ino_limit = 0xffffffff;
	dqopt->info[type].dqi_igrace =
			dqblk.dqb_itime ? dqblk.dqb_itime : MAX_IQ_TIME;
	dqopt->info[type].dqi_bgrace =
			dqblk.dqb_btime ? dqblk.dqb_btime : MAX_DQ_TIME;
out:
	up_read(&dqopt->dqio_sem);
	return ret;
}

static int v1_write_file_info(struct super_block *sb, int type)
{
	struct quota_info *dqopt = sb_dqopt(sb);
	struct v1_disk_dqblk dqblk;
	int ret;

	down_write(&dqopt->dqio_sem);
	ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
				sizeof(struct v1_disk_dqblk), v1_dqoff(0));
	if (ret != sizeof(struct v1_disk_dqblk)) {
		if (ret >= 0)
			ret = -EIO;
		goto out;
	}
	spin_lock(&dq_data_lock);
	dqopt->info[type].dqi_flags &= ~DQF_INFO_DIRTY;
	dqblk.dqb_itime = dqopt->info[type].dqi_igrace;
	dqblk.dqb_btime = dqopt->info[type].dqi_bgrace;
	spin_unlock(&dq_data_lock);
	ret = sb->s_op->quota_write(sb, type, (char *)&dqblk,
	      sizeof(struct v1_disk_dqblk), v1_dqoff(0));
	if (ret == sizeof(struct v1_disk_dqblk))
		ret = 0;
	else if (ret > 0)
		ret = -EIO;
out:
	up_write(&dqopt->dqio_sem);
	return ret;
}

static const struct quota_format_ops v1_format_ops = {
	.check_quota_file	= v1_check_quota_file,
	.read_file_info		= v1_read_file_info,
	.write_file_info	= v1_write_file_info,
	.free_file_info		= NULL,
	.read_dqblk		= v1_read_dqblk,
	.commit_dqblk		= v1_commit_dqblk,
};

static struct quota_format_type v1_quota_format = {
	.qf_fmt_id	= QFMT_VFS_OLD,
	.qf_ops		= &v1_format_ops,
	.qf_owner	= THIS_MODULE
};

static int __init init_v1_quota_format(void)
{
        return register_quota_format(&v1_quota_format);
}

static void __exit exit_v1_quota_format(void)
{
        unregister_quota_format(&v1_quota_format);
}

module_init(init_v1_quota_format);
module_exit(exit_v1_quota_format);
Commit	Line	Data
1da177e4 LT	1	#include <linux/errno.h>
	2	#include <linux/fs.h>
	3	#include <linux/quota.h>
74abb989	4	#include <linux/quotaops.h>
1da177e4	5	#include <linux/dqblk_v1.h>
1da177e4 LT	6	#include <linux/kernel.h>
	7	#include <linux/init.h>
	8	#include <linux/module.h>
	9
	10	#include <asm/byteorder.h>
	11
cf770c13 JK	12	#include "quotaio_v1.h"
cf770c13 JK	13
1da177e4 LT	14	MODULE_AUTHOR("Jan Kara");
	15	MODULE_DESCRIPTION("Old quota format support");
	16	MODULE_LICENSE("GPL");
	17
12095460 JK	18	#define QUOTABLOCK_BITS 10
	19	#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
	20
	21	static inline qsize_t v1_stoqb(qsize_t space)
	22	{
	23	return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
	24	}
	25
	26	static inline qsize_t v1_qbtos(qsize_t blocks)
	27	{
	28	return blocks << QUOTABLOCK_BITS;
	29	}
	30
1da177e4 LT	31	static void v1_disk2mem_dqblk(struct mem_dqblk m, struct v1_disk_dqblk d)
	32	{
	33	m->dqb_ihardlimit = d->dqb_ihardlimit;
	34	m->dqb_isoftlimit = d->dqb_isoftlimit;
	35	m->dqb_curinodes = d->dqb_curinodes;
12095460 JK	36	m->dqb_bhardlimit = v1_qbtos(d->dqb_bhardlimit);
	37	m->dqb_bsoftlimit = v1_qbtos(d->dqb_bsoftlimit);
	38	m->dqb_curspace = v1_qbtos(d->dqb_curblocks);
1da177e4 LT	39	m->dqb_itime = d->dqb_itime;
	40	m->dqb_btime = d->dqb_btime;
	41	}
	42
	43	static void v1_mem2disk_dqblk(struct v1_disk_dqblk d, struct mem_dqblk m)
	44	{
	45	d->dqb_ihardlimit = m->dqb_ihardlimit;
	46	d->dqb_isoftlimit = m->dqb_isoftlimit;
	47	d->dqb_curinodes = m->dqb_curinodes;
12095460 JK	48	d->dqb_bhardlimit = v1_stoqb(m->dqb_bhardlimit);
	49	d->dqb_bsoftlimit = v1_stoqb(m->dqb_bsoftlimit);
	50	d->dqb_curblocks = v1_stoqb(m->dqb_curspace);
1da177e4 LT	51	d->dqb_itime = m->dqb_itime;
	52	d->dqb_btime = m->dqb_btime;
	53	}
	54
	55	static int v1_read_dqblk(struct dquot *dquot)
	56	{
4c376dca	57	int type = dquot->dq_id.type;
1da177e4	58	struct v1_disk_dqblk dqblk;
e342e38d	59	struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
1da177e4	60
e342e38d	61	if (!dqopt->files[type])
1da177e4 LT	62	return -EINVAL;
	63
	64	/* Set structure to 0s in case read fails/is after end of file */
	65	memset(&dqblk, 0, sizeof(struct v1_disk_dqblk));
268157ba	66	dquot->dq_sb->s_op->quota_read(dquot->dq_sb, type, (char *)&dqblk,
4c376dca EB	67	sizeof(struct v1_disk_dqblk),
4c376dca EB	68	v1_dqoff(from_kqid(&init_user_ns, dquot->dq_id)));
1da177e4 LT	69
1da177e4 LT	70	v1_disk2mem_dqblk(&dquot->dq_dqb, &dqblk);
268157ba JK	71	if (dquot->dq_dqb.dqb_bhardlimit == 0 &&
	72	dquot->dq_dqb.dqb_bsoftlimit == 0 &&
	73	dquot->dq_dqb.dqb_ihardlimit == 0 &&
	74	dquot->dq_dqb.dqb_isoftlimit == 0)
1da177e4	75	set_bit(DQ_FAKE_B, &dquot->dq_flags);
dde95888	76	dqstats_inc(DQST_READS);
1da177e4 LT	77
	78	return 0;
	79	}
	80
	81	static int v1_commit_dqblk(struct dquot *dquot)
	82	{
4c376dca	83	short type = dquot->dq_id.type;
1da177e4 LT	84	ssize_t ret;
	85	struct v1_disk_dqblk dqblk;
	86
	87	v1_mem2disk_dqblk(&dqblk, &dquot->dq_dqb);
4c376dca EB	88	if (((type == USRQUOTA) && uid_eq(dquot->dq_id.uid, GLOBAL_ROOT_UID)) \|\|
4c376dca EB	89	((type == GRPQUOTA) && gid_eq(dquot->dq_id.gid, GLOBAL_ROOT_GID))) {
268157ba JK	90	dqblk.dqb_btime =
	91	sb_dqopt(dquot->dq_sb)->info[type].dqi_bgrace;
	92	dqblk.dqb_itime =
	93	sb_dqopt(dquot->dq_sb)->info[type].dqi_igrace;
1da177e4 LT	94	}
	95	ret = 0;
	96	if (sb_dqopt(dquot->dq_sb)->files[type])
268157ba JK	97	ret = dquot->dq_sb->s_op->quota_write(dquot->dq_sb, type,
268157ba JK	98	(char *)&dqblk, sizeof(struct v1_disk_dqblk),
4c376dca	99	v1_dqoff(from_kqid(&init_user_ns, dquot->dq_id)));
1da177e4	100	if (ret != sizeof(struct v1_disk_dqblk)) {
fb5ffb0e	101	quota_error(dquot->dq_sb, "dquota write failed");
1da177e4 LT	102	if (ret >= 0)
	103	ret = -EIO;
	104	goto out;
	105	}
	106	ret = 0;
	107
	108	out:
dde95888	109	dqstats_inc(DQST_WRITES);
1da177e4 LT	110
	111	return ret;
	112	}
	113
	114	/* Magics of new quota format */
	115	#define V2_INITQMAGICS {\
	116	0xd9c01f11, /* USRQUOTA */\
	117	0xd9c01927 /* GRPQUOTA */\
	118	}
	119
	120	/* Header of new quota format */
	121	struct v2_disk_dqheader {
	122	__le32 dqh_magic; /* Magic number identifying file */
	123	__le32 dqh_version; /* File version */
	124	};
	125
	126	static int v1_check_quota_file(struct super_block *sb, int type)
	127	{
	128	struct inode *inode = sb_dqopt(sb)->files[type];
	129	ulong blocks;
	130	size_t off;
	131	struct v2_disk_dqheader dqhead;
	132	ssize_t size;
	133	loff_t isize;
	134	static const uint quota_magics[] = V2_INITQMAGICS;
	135
	136	isize = i_size_read(inode);
	137	if (!isize)
	138	return 0;
	139	blocks = isize >> BLOCK_SIZE_BITS;
	140	off = isize & (BLOCK_SIZE - 1);
268157ba JK	141	if ((blocks % sizeof(struct v1_disk_dqblk) * BLOCK_SIZE + off) %
268157ba JK	142	sizeof(struct v1_disk_dqblk))
1da177e4	143	return 0;
268157ba JK	144	/* Doublecheck whether we didn't get file with new format - with old
	145	* quotactl() this could happen */
	146	size = sb->s_op->quota_read(sb, type, (char *)&dqhead,
	147	sizeof(struct v2_disk_dqheader), 0);
1da177e4 LT	148	if (size != sizeof(struct v2_disk_dqheader))
	149	return 1; /* Probably not new format */
	150	if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type])
	151	return 1; /* Definitely not new format */
268157ba JK	152	printk(KERN_INFO
	153	"VFS: %s: Refusing to turn on old quota format on given file."
	154	" It probably contains newer quota format.\n", sb->s_id);
1da177e4 LT	155	return 0; /* Seems like a new format file -> refuse it */
	156	}
	157
	158	static int v1_read_file_info(struct super_block *sb, int type)
	159	{
	160	struct quota_info *dqopt = sb_dqopt(sb);
	161	struct v1_disk_dqblk dqblk;
	162	int ret;
	163
42fdb858	164	down_read(&dqopt->dqio_sem);
268157ba JK	165	ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
	166	sizeof(struct v1_disk_dqblk), v1_dqoff(0));
	167	if (ret != sizeof(struct v1_disk_dqblk)) {
1da177e4 LT	168	if (ret >= 0)
	169	ret = -EIO;
	170	goto out;
	171	}
	172	ret = 0;
338bf9af	173	/* limits are stored as unsigned 32-bit data */
b10a0819 JK	174	dqopt->info[type].dqi_max_spc_limit = 0xffffffffULL << QUOTABLOCK_BITS;
b10a0819 JK	175	dqopt->info[type].dqi_max_ino_limit = 0xffffffff;
268157ba JK	176	dqopt->info[type].dqi_igrace =
	177	dqblk.dqb_itime ? dqblk.dqb_itime : MAX_IQ_TIME;
	178	dqopt->info[type].dqi_bgrace =
	179	dqblk.dqb_btime ? dqblk.dqb_btime : MAX_DQ_TIME;
1da177e4	180	out:
42fdb858	181	up_read(&dqopt->dqio_sem);
1da177e4 LT	182	return ret;
	183	}
	184
	185	static int v1_write_file_info(struct super_block *sb, int type)
	186	{
	187	struct quota_info *dqopt = sb_dqopt(sb);
	188	struct v1_disk_dqblk dqblk;
	189	int ret;
	190
9a8ae30e	191	down_write(&dqopt->dqio_sem);
268157ba JK	192	ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
	193	sizeof(struct v1_disk_dqblk), v1_dqoff(0));
	194	if (ret != sizeof(struct v1_disk_dqblk)) {
1da177e4 LT	195	if (ret >= 0)
	196	ret = -EIO;
	197	goto out;
	198	}
15512377 JK	199	spin_lock(&dq_data_lock);
15512377 JK	200	dqopt->info[type].dqi_flags &= ~DQF_INFO_DIRTY;
1da177e4 LT	201	dqblk.dqb_itime = dqopt->info[type].dqi_igrace;
1da177e4 LT	202	dqblk.dqb_btime = dqopt->info[type].dqi_bgrace;
15512377	203	spin_unlock(&dq_data_lock);
1da177e4 LT	204	ret = sb->s_op->quota_write(sb, type, (char *)&dqblk,
	205	sizeof(struct v1_disk_dqblk), v1_dqoff(0));
	206	if (ret == sizeof(struct v1_disk_dqblk))
	207	ret = 0;
	208	else if (ret > 0)
	209	ret = -EIO;
	210	out:
9a8ae30e	211	up_write(&dqopt->dqio_sem);
1da177e4 LT	212	return ret;
	213	}
	214
1472da5f	215	static const struct quota_format_ops v1_format_ops = {
1da177e4 LT	216	.check_quota_file = v1_check_quota_file,
	217	.read_file_info = v1_read_file_info,
	218	.write_file_info = v1_write_file_info,
	219	.free_file_info = NULL,
	220	.read_dqblk = v1_read_dqblk,
	221	.commit_dqblk = v1_commit_dqblk,
	222	};
	223
	224	static struct quota_format_type v1_quota_format = {
	225	.qf_fmt_id = QFMT_VFS_OLD,
	226	.qf_ops = &v1_format_ops,
	227	.qf_owner = THIS_MODULE
	228	};
	229
	230	static int __init init_v1_quota_format(void)
	231	{
	232	return register_quota_format(&v1_quota_format);
	233	}
	234
	235	static void __exit exit_v1_quota_format(void)
	236	{
	237	unregister_quota_format(&v1_quota_format);
	238	}
	239
	240	module_init(init_v1_quota_format);
	241	module_exit(exit_v1_quota_format);
	242