aboutsummaryrefslogtreecommitdiff
path: root/fs/quota/quota_v2.c
blob: 01f25eae684d858d43254fb33e049af30f134fd7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
/*
 *	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 v2_mem2diskdqb(void *dp, struct dquot *dquot);
static void v2_disk2memdqb(struct dquot *dquot, void *dp);
static int v2_is_id(void *dp, struct dquot *dquot);

static struct qtree_fmt_operations v2_qtree_ops = {
	.mem2disk_dqblk = v2_mem2diskdqb,
	.disk2mem_dqblk = v2_disk2memdqb,
	.is_id = v2_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;
}

/* 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;
	ssize_t size;
	static const uint quota_magics[] = V2_INITQMAGICS;
	static const uint quota_versions[] = V2_INITQVERSIONS;
 
	size = sb->s_op->quota_read(sb, type, (char *)&dqhead,
				    sizeof(struct v2_disk_dqheader), 0);
	if (size != sizeof(struct v2_disk_dqheader)) {
		printk("quota_v2: failed read expected=%zd got=%zd\n",
			sizeof(struct v2_disk_dqheader), size);
		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 mem_dqinfo *info = sb_dqinfo(sb, type);
	struct qtree_mem_dqinfo *qinfo;
	ssize_t size;

	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 "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;
	/* limits are stored as unsigned 32-bit data */
	info->dqi_maxblimit = 0xffffffff;
	info->dqi_maxilimit = 0xffffffff;
	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);
	qinfo->dqi_entry_size = sizeof(struct v2_disk_dqblk);
	qinfo->dqi_ops = &v2_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 v2_disk2memdqb(struct dquot *dquot, void *dp)
{
	struct v2_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 v2_disk_dqblk));
	empty.dqb_itime = cpu_to_le64(1);
	if (!memcmp(&empty, dp, sizeof(struct v2_disk_dqblk)))
		m->dqb_itime = 0;
}

static void v2_mem2diskdqb(void *dp, struct dquot *dquot)
{
	struct v2_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 v2_is_id(void *dp, struct dquot *dquot)
{
	struct v2_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 v2_quota_format = {
	.qf_fmt_id	= QFMT_VFS_V0,
	.qf_ops		= &v2_format_ops,
	.qf_owner	= THIS_MODULE
};

static int __init init_v2_quota_format(void)
{
	return register_quota_format(&v2_quota_format);
}

static void __exit exit_v2_quota_format(void)
{
	unregister_quota_format(&v2_quota_format);
}

module_init(init_v2_quota_format);
module_exit(exit_v2_quota_format);