linux/fs/quota/quota_v2.c
Jan Kara 869835dfad quota: Improve checking of quota file header
When we are asked for vfsv0 quota format and the file is in vfsv1
format (or vice versa), refuse to use the quota file. Also return
with error when we don't like the header of quota file.

Signed-off-by: Jan Kara <jack@suse.cz>
2009-12-23 13:44:13 +01:00

339 lines
10 KiB
C

/*
* vfsv0 quota IO operations on file
*/
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/dqblk_v2.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/quotaops.h>
#include <asm/byteorder.h>
#include "quota_tree.h"
#include "quotaio_v2.h"
MODULE_AUTHOR("Jan Kara");
MODULE_DESCRIPTION("Quota format v2 support");
MODULE_LICENSE("GPL");
#define __QUOTA_V2_PARANOIA
static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot);
static void v2r0_disk2memdqb(struct dquot *dquot, void *dp);
static int v2r0_is_id(void *dp, struct dquot *dquot);
static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot);
static void v2r1_disk2memdqb(struct dquot *dquot, void *dp);
static int v2r1_is_id(void *dp, struct dquot *dquot);
static struct qtree_fmt_operations v2r0_qtree_ops = {
.mem2disk_dqblk = v2r0_mem2diskdqb,
.disk2mem_dqblk = v2r0_disk2memdqb,
.is_id = v2r0_is_id,
};
static struct qtree_fmt_operations v2r1_qtree_ops = {
.mem2disk_dqblk = v2r1_mem2diskdqb,
.disk2mem_dqblk = v2r1_disk2memdqb,
.is_id = v2r1_is_id,
};
#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;
}
static int v2_read_header(struct super_block *sb, int type,
struct v2_disk_dqheader *dqhead)
{
ssize_t size;
size = sb->s_op->quota_read(sb, type, (char *)dqhead,
sizeof(struct v2_disk_dqheader), 0);
if (size != sizeof(struct v2_disk_dqheader)) {
printk(KERN_WARNING "quota_v2: Failed header read:"
" expected=%zd got=%zd\n",
sizeof(struct v2_disk_dqheader), size);
return 0;
}
return 1;
}
/* Check whether given file is really vfsv0 quotafile */
static int v2_check_quota_file(struct super_block *sb, int type)
{
struct v2_disk_dqheader dqhead;
static const uint quota_magics[] = V2_INITQMAGICS;
static const uint quota_versions[] = V2_INITQVERSIONS;
if (!v2_read_header(sb, type, &dqhead))
return 0;
if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] ||
le32_to_cpu(dqhead.dqh_version) > quota_versions[type])
return 0;
return 1;
}
/* Read information header from quota file */
static int v2_read_file_info(struct super_block *sb, int type)
{
struct v2_disk_dqinfo dinfo;
struct v2_disk_dqheader dqhead;
struct mem_dqinfo *info = sb_dqinfo(sb, type);
struct qtree_mem_dqinfo *qinfo;
ssize_t size;
unsigned int version;
if (!v2_read_header(sb, type, &dqhead))
return -1;
version = le32_to_cpu(dqhead.dqh_version);
if ((info->dqi_fmt_id == QFMT_VFS_V0 && version != 0) ||
(info->dqi_fmt_id == QFMT_VFS_V1 && version != 1))
return -1;
size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
if (size != sizeof(struct v2_disk_dqinfo)) {
printk(KERN_WARNING "quota_v2: Can't read info structure on device %s.\n",
sb->s_id);
return -1;
}
info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
if (!info->dqi_priv) {
printk(KERN_WARNING
"Not enough memory for quota information structure.\n");
return -1;
}
qinfo = info->dqi_priv;
if (version == 0) {
/* limits are stored as unsigned 32-bit data */
info->dqi_maxblimit = 0xffffffff;
info->dqi_maxilimit = 0xffffffff;
} else {
/* used space is stored as unsigned 64-bit value */
info->dqi_maxblimit = 0xffffffffffffffffULL; /* 2^64-1 */
info->dqi_maxilimit = 0xffffffffffffffffULL;
}
info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
info->dqi_flags = le32_to_cpu(dinfo.dqi_flags);
qinfo->dqi_sb = sb;
qinfo->dqi_type = type;
qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
qinfo->dqi_qtree_depth = qtree_depth(qinfo);
if (version == 0) {
qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
qinfo->dqi_ops = &v2r0_qtree_ops;
} else {
qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
qinfo->dqi_ops = &v2r1_qtree_ops;
}
return 0;
}
/* Write information header to quota file */
static int v2_write_file_info(struct super_block *sb, int type)
{
struct v2_disk_dqinfo dinfo;
struct mem_dqinfo *info = sb_dqinfo(sb, type);
struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
ssize_t size;
spin_lock(&dq_data_lock);
info->dqi_flags &= ~DQF_INFO_DIRTY;
dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
dinfo.dqi_flags = cpu_to_le32(info->dqi_flags & DQF_MASK);
spin_unlock(&dq_data_lock);
dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
if (size != sizeof(struct v2_disk_dqinfo)) {
printk(KERN_WARNING "Can't write info structure on device %s.\n",
sb->s_id);
return -1;
}
return 0;
}
static void v2r0_disk2memdqb(struct dquot *dquot, void *dp)
{
struct v2r0_disk_dqblk *d = dp, empty;
struct mem_dqblk *m = &dquot->dq_dqb;
m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
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 = 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);
/* We need to escape back all-zero structure */
memset(&empty, 0, sizeof(struct v2r0_disk_dqblk));
empty.dqb_itime = cpu_to_le64(1);
if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk)))
m->dqb_itime = 0;
}
static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot)
{
struct v2r0_disk_dqblk *d = dp;
struct mem_dqblk *m = &dquot->dq_dqb;
struct qtree_mem_dqinfo *info =
sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
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(v2_stoqb(m->dqb_bhardlimit));
d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(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(dquot->dq_id);
if (qtree_entry_unused(info, dp))
d->dqb_itime = cpu_to_le64(1);
}
static int v2r0_is_id(void *dp, struct dquot *dquot)
{
struct v2r0_disk_dqblk *d = dp;
struct qtree_mem_dqinfo *info =
sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
if (qtree_entry_unused(info, dp))
return 0;
return le32_to_cpu(d->dqb_id) == dquot->dq_id;
}
static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
{
struct v2r1_disk_dqblk *d = dp, empty;
struct mem_dqblk *m = &dquot->dq_dqb;
m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
m->dqb_itime = le64_to_cpu(d->dqb_itime);
m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
m->dqb_btime = le64_to_cpu(d->dqb_btime);
/* We need to escape back all-zero structure */
memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
empty.dqb_itime = cpu_to_le64(1);
if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
m->dqb_itime = 0;
}
static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
{
struct v2r1_disk_dqblk *d = dp;
struct mem_dqblk *m = &dquot->dq_dqb;
struct qtree_mem_dqinfo *info =
sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
d->dqb_itime = cpu_to_le64(m->dqb_itime);
d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(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(dquot->dq_id);
if (qtree_entry_unused(info, dp))
d->dqb_itime = cpu_to_le64(1);
}
static int v2r1_is_id(void *dp, struct dquot *dquot)
{
struct v2r1_disk_dqblk *d = dp;
struct qtree_mem_dqinfo *info =
sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
if (qtree_entry_unused(info, dp))
return 0;
return le32_to_cpu(d->dqb_id) == dquot->dq_id;
}
static int v2_read_dquot(struct dquot *dquot)
{
return qtree_read_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
}
static int v2_write_dquot(struct dquot *dquot)
{
return qtree_write_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
}
static int v2_release_dquot(struct dquot *dquot)
{
return qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
}
static int v2_free_file_info(struct super_block *sb, int type)
{
kfree(sb_dqinfo(sb, type)->dqi_priv);
return 0;
}
static const struct quota_format_ops v2_format_ops = {
.check_quota_file = v2_check_quota_file,
.read_file_info = v2_read_file_info,
.write_file_info = v2_write_file_info,
.free_file_info = v2_free_file_info,
.read_dqblk = v2_read_dquot,
.commit_dqblk = v2_write_dquot,
.release_dqblk = v2_release_dquot,
};
static struct quota_format_type v2r0_quota_format = {
.qf_fmt_id = QFMT_VFS_V0,
.qf_ops = &v2_format_ops,
.qf_owner = THIS_MODULE
};
static struct quota_format_type v2r1_quota_format = {
.qf_fmt_id = QFMT_VFS_V1,
.qf_ops = &v2_format_ops,
.qf_owner = THIS_MODULE
};
static int __init init_v2_quota_format(void)
{
int ret;
ret = register_quota_format(&v2r0_quota_format);
if (ret)
return ret;
return register_quota_format(&v2r1_quota_format);
}
static void __exit exit_v2_quota_format(void)
{
unregister_quota_format(&v2r0_quota_format);
unregister_quota_format(&v2r1_quota_format);
}
module_init(init_v2_quota_format);
module_exit(exit_v2_quota_format);