Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[linux-2.6-block.git] / fs / quota / quota_v1.c
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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"
13
1da177e4
LT
14MODULE_AUTHOR("Jan Kara");
15MODULE_DESCRIPTION("Old quota format support");
16MODULE_LICENSE("GPL");
17
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18#define QUOTABLOCK_BITS 10
19#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
20
21static inline qsize_t v1_stoqb(qsize_t space)
22{
23 return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
24}
25
26static inline qsize_t v1_qbtos(qsize_t blocks)
27{
28 return blocks << QUOTABLOCK_BITS;
29}
30
1da177e4
LT
31static 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;
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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
43static 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;
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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
55static int v1_read_dqblk(struct dquot *dquot)
56{
57 int type = dquot->dq_type;
58 struct v1_disk_dqblk dqblk;
59
60 if (!sb_dqopt(dquot->dq_sb)->files[type])
61 return -EINVAL;
62
63 /* Set structure to 0s in case read fails/is after end of file */
64 memset(&dqblk, 0, sizeof(struct v1_disk_dqblk));
268157ba
JK
65 dquot->dq_sb->s_op->quota_read(dquot->dq_sb, type, (char *)&dqblk,
66 sizeof(struct v1_disk_dqblk), v1_dqoff(dquot->dq_id));
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67
68 v1_disk2mem_dqblk(&dquot->dq_dqb, &dqblk);
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JK
69 if (dquot->dq_dqb.dqb_bhardlimit == 0 &&
70 dquot->dq_dqb.dqb_bsoftlimit == 0 &&
71 dquot->dq_dqb.dqb_ihardlimit == 0 &&
72 dquot->dq_dqb.dqb_isoftlimit == 0)
1da177e4
LT
73 set_bit(DQ_FAKE_B, &dquot->dq_flags);
74 dqstats.reads++;
75
76 return 0;
77}
78
79static int v1_commit_dqblk(struct dquot *dquot)
80{
81 short type = dquot->dq_type;
82 ssize_t ret;
83 struct v1_disk_dqblk dqblk;
84
85 v1_mem2disk_dqblk(&dqblk, &dquot->dq_dqb);
86 if (dquot->dq_id == 0) {
268157ba
JK
87 dqblk.dqb_btime =
88 sb_dqopt(dquot->dq_sb)->info[type].dqi_bgrace;
89 dqblk.dqb_itime =
90 sb_dqopt(dquot->dq_sb)->info[type].dqi_igrace;
1da177e4
LT
91 }
92 ret = 0;
93 if (sb_dqopt(dquot->dq_sb)->files[type])
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94 ret = dquot->dq_sb->s_op->quota_write(dquot->dq_sb, type,
95 (char *)&dqblk, sizeof(struct v1_disk_dqblk),
96 v1_dqoff(dquot->dq_id));
1da177e4
LT
97 if (ret != sizeof(struct v1_disk_dqblk)) {
98 printk(KERN_WARNING "VFS: dquota write failed on dev %s\n",
99 dquot->dq_sb->s_id);
100 if (ret >= 0)
101 ret = -EIO;
102 goto out;
103 }
104 ret = 0;
105
106out:
107 dqstats.writes++;
108
109 return ret;
110}
111
112/* Magics of new quota format */
113#define V2_INITQMAGICS {\
114 0xd9c01f11, /* USRQUOTA */\
115 0xd9c01927 /* GRPQUOTA */\
116}
117
118/* Header of new quota format */
119struct v2_disk_dqheader {
120 __le32 dqh_magic; /* Magic number identifying file */
121 __le32 dqh_version; /* File version */
122};
123
124static int v1_check_quota_file(struct super_block *sb, int type)
125{
126 struct inode *inode = sb_dqopt(sb)->files[type];
127 ulong blocks;
128 size_t off;
129 struct v2_disk_dqheader dqhead;
130 ssize_t size;
131 loff_t isize;
132 static const uint quota_magics[] = V2_INITQMAGICS;
133
134 isize = i_size_read(inode);
135 if (!isize)
136 return 0;
137 blocks = isize >> BLOCK_SIZE_BITS;
138 off = isize & (BLOCK_SIZE - 1);
268157ba
JK
139 if ((blocks % sizeof(struct v1_disk_dqblk) * BLOCK_SIZE + off) %
140 sizeof(struct v1_disk_dqblk))
1da177e4 141 return 0;
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142 /* Doublecheck whether we didn't get file with new format - with old
143 * quotactl() this could happen */
144 size = sb->s_op->quota_read(sb, type, (char *)&dqhead,
145 sizeof(struct v2_disk_dqheader), 0);
1da177e4
LT
146 if (size != sizeof(struct v2_disk_dqheader))
147 return 1; /* Probably not new format */
148 if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type])
149 return 1; /* Definitely not new format */
268157ba
JK
150 printk(KERN_INFO
151 "VFS: %s: Refusing to turn on old quota format on given file."
152 " It probably contains newer quota format.\n", sb->s_id);
1da177e4
LT
153 return 0; /* Seems like a new format file -> refuse it */
154}
155
156static int v1_read_file_info(struct super_block *sb, int type)
157{
158 struct quota_info *dqopt = sb_dqopt(sb);
159 struct v1_disk_dqblk dqblk;
160 int ret;
161
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162 ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
163 sizeof(struct v1_disk_dqblk), v1_dqoff(0));
164 if (ret != sizeof(struct v1_disk_dqblk)) {
1da177e4
LT
165 if (ret >= 0)
166 ret = -EIO;
167 goto out;
168 }
169 ret = 0;
338bf9af
AP
170 /* limits are stored as unsigned 32-bit data */
171 dqopt->info[type].dqi_maxblimit = 0xffffffff;
172 dqopt->info[type].dqi_maxilimit = 0xffffffff;
268157ba
JK
173 dqopt->info[type].dqi_igrace =
174 dqblk.dqb_itime ? dqblk.dqb_itime : MAX_IQ_TIME;
175 dqopt->info[type].dqi_bgrace =
176 dqblk.dqb_btime ? dqblk.dqb_btime : MAX_DQ_TIME;
1da177e4
LT
177out:
178 return ret;
179}
180
181static int v1_write_file_info(struct super_block *sb, int type)
182{
183 struct quota_info *dqopt = sb_dqopt(sb);
184 struct v1_disk_dqblk dqblk;
185 int ret;
186
187 dqopt->info[type].dqi_flags &= ~DQF_INFO_DIRTY;
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JK
188 ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
189 sizeof(struct v1_disk_dqblk), v1_dqoff(0));
190 if (ret != sizeof(struct v1_disk_dqblk)) {
1da177e4
LT
191 if (ret >= 0)
192 ret = -EIO;
193 goto out;
194 }
195 dqblk.dqb_itime = dqopt->info[type].dqi_igrace;
196 dqblk.dqb_btime = dqopt->info[type].dqi_bgrace;
197 ret = sb->s_op->quota_write(sb, type, (char *)&dqblk,
198 sizeof(struct v1_disk_dqblk), v1_dqoff(0));
199 if (ret == sizeof(struct v1_disk_dqblk))
200 ret = 0;
201 else if (ret > 0)
202 ret = -EIO;
203out:
204 return ret;
205}
206
1472da5f 207static const struct quota_format_ops v1_format_ops = {
1da177e4
LT
208 .check_quota_file = v1_check_quota_file,
209 .read_file_info = v1_read_file_info,
210 .write_file_info = v1_write_file_info,
211 .free_file_info = NULL,
212 .read_dqblk = v1_read_dqblk,
213 .commit_dqblk = v1_commit_dqblk,
214};
215
216static struct quota_format_type v1_quota_format = {
217 .qf_fmt_id = QFMT_VFS_OLD,
218 .qf_ops = &v1_format_ops,
219 .qf_owner = THIS_MODULE
220};
221
222static int __init init_v1_quota_format(void)
223{
224 return register_quota_format(&v1_quota_format);
225}
226
227static void __exit exit_v1_quota_format(void)
228{
229 unregister_quota_format(&v1_quota_format);
230}
231
232module_init(init_v1_quota_format);
233module_exit(exit_v1_quota_format);
234