device create: misc: convert device_create_drvdata to device_create
[linux-2.6.git] / fs / quota_v1.c
1 #include <linux/errno.h>
2 #include <linux/fs.h>
3 #include <linux/quota.h>
4 #include <linux/quotaops.h>
5 #include <linux/dqblk_v1.h>
6 #include <linux/quotaio_v1.h>
7 #include <linux/kernel.h>
8 #include <linux/init.h>
9 #include <linux/module.h>
10
11 #include <asm/byteorder.h>
12
13 MODULE_AUTHOR("Jan Kara");
14 MODULE_DESCRIPTION("Old quota format support");
15 MODULE_LICENSE("GPL");
16
17 static void v1_disk2mem_dqblk(struct mem_dqblk *m, struct v1_disk_dqblk *d)
18 {
19         m->dqb_ihardlimit = d->dqb_ihardlimit;
20         m->dqb_isoftlimit = d->dqb_isoftlimit;
21         m->dqb_curinodes = d->dqb_curinodes;
22         m->dqb_bhardlimit = d->dqb_bhardlimit;
23         m->dqb_bsoftlimit = d->dqb_bsoftlimit;
24         m->dqb_curspace = ((qsize_t)d->dqb_curblocks) << QUOTABLOCK_BITS;
25         m->dqb_itime = d->dqb_itime;
26         m->dqb_btime = d->dqb_btime;
27 }
28
29 static void v1_mem2disk_dqblk(struct v1_disk_dqblk *d, struct mem_dqblk *m)
30 {
31         d->dqb_ihardlimit = m->dqb_ihardlimit;
32         d->dqb_isoftlimit = m->dqb_isoftlimit;
33         d->dqb_curinodes = m->dqb_curinodes;
34         d->dqb_bhardlimit = m->dqb_bhardlimit;
35         d->dqb_bsoftlimit = m->dqb_bsoftlimit;
36         d->dqb_curblocks = toqb(m->dqb_curspace);
37         d->dqb_itime = m->dqb_itime;
38         d->dqb_btime = m->dqb_btime;
39 }
40
41 static int v1_read_dqblk(struct dquot *dquot)
42 {
43         int type = dquot->dq_type;
44         struct v1_disk_dqblk dqblk;
45
46         if (!sb_dqopt(dquot->dq_sb)->files[type])
47                 return -EINVAL;
48
49         /* Set structure to 0s in case read fails/is after end of file */
50         memset(&dqblk, 0, sizeof(struct v1_disk_dqblk));
51         dquot->dq_sb->s_op->quota_read(dquot->dq_sb, type, (char *)&dqblk, sizeof(struct v1_disk_dqblk), v1_dqoff(dquot->dq_id));
52
53         v1_disk2mem_dqblk(&dquot->dq_dqb, &dqblk);
54         if (dquot->dq_dqb.dqb_bhardlimit == 0 && dquot->dq_dqb.dqb_bsoftlimit == 0 &&
55             dquot->dq_dqb.dqb_ihardlimit == 0 && dquot->dq_dqb.dqb_isoftlimit == 0)
56                 set_bit(DQ_FAKE_B, &dquot->dq_flags);
57         dqstats.reads++;
58
59         return 0;
60 }
61
62 static int v1_commit_dqblk(struct dquot *dquot)
63 {
64         short type = dquot->dq_type;
65         ssize_t ret;
66         struct v1_disk_dqblk dqblk;
67
68         v1_mem2disk_dqblk(&dqblk, &dquot->dq_dqb);
69         if (dquot->dq_id == 0) {
70                 dqblk.dqb_btime = sb_dqopt(dquot->dq_sb)->info[type].dqi_bgrace;
71                 dqblk.dqb_itime = sb_dqopt(dquot->dq_sb)->info[type].dqi_igrace;
72         }
73         ret = 0;
74         if (sb_dqopt(dquot->dq_sb)->files[type])
75                 ret = dquot->dq_sb->s_op->quota_write(dquot->dq_sb, type, (char *)&dqblk,
76                                         sizeof(struct v1_disk_dqblk), v1_dqoff(dquot->dq_id));
77         if (ret != sizeof(struct v1_disk_dqblk)) {
78                 printk(KERN_WARNING "VFS: dquota write failed on dev %s\n",
79                         dquot->dq_sb->s_id);
80                 if (ret >= 0)
81                         ret = -EIO;
82                 goto out;
83         }
84         ret = 0;
85
86 out:
87         dqstats.writes++;
88
89         return ret;
90 }
91
92 /* Magics of new quota format */
93 #define V2_INITQMAGICS {\
94         0xd9c01f11,     /* USRQUOTA */\
95         0xd9c01927      /* GRPQUOTA */\
96 }
97
98 /* Header of new quota format */
99 struct v2_disk_dqheader {
100         __le32 dqh_magic;        /* Magic number identifying file */
101         __le32 dqh_version;      /* File version */
102 };
103
104 static int v1_check_quota_file(struct super_block *sb, int type)
105 {
106         struct inode *inode = sb_dqopt(sb)->files[type];
107         ulong blocks;
108         size_t off; 
109         struct v2_disk_dqheader dqhead;
110         ssize_t size;
111         loff_t isize;
112         static const uint quota_magics[] = V2_INITQMAGICS;
113
114         isize = i_size_read(inode);
115         if (!isize)
116                 return 0;
117         blocks = isize >> BLOCK_SIZE_BITS;
118         off = isize & (BLOCK_SIZE - 1);
119         if ((blocks % sizeof(struct v1_disk_dqblk) * BLOCK_SIZE + off) % sizeof(struct v1_disk_dqblk))
120                 return 0;
121         /* Doublecheck whether we didn't get file with new format - with old quotactl() this could happen */
122         size = sb->s_op->quota_read(sb, type, (char *)&dqhead, sizeof(struct v2_disk_dqheader), 0);
123         if (size != sizeof(struct v2_disk_dqheader))
124                 return 1;       /* Probably not new format */
125         if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type])
126                 return 1;       /* Definitely not new format */
127         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);
128         return 0;               /* Seems like a new format file -> refuse it */
129 }
130
131 static int v1_read_file_info(struct super_block *sb, int type)
132 {
133         struct quota_info *dqopt = sb_dqopt(sb);
134         struct v1_disk_dqblk dqblk;
135         int ret;
136
137         if ((ret = sb->s_op->quota_read(sb, type, (char *)&dqblk, sizeof(struct v1_disk_dqblk), v1_dqoff(0))) != sizeof(struct v1_disk_dqblk)) {
138                 if (ret >= 0)
139                         ret = -EIO;
140                 goto out;
141         }
142         ret = 0;
143         /* limits are stored as unsigned 32-bit data */
144         dqopt->info[type].dqi_maxblimit = 0xffffffff;
145         dqopt->info[type].dqi_maxilimit = 0xffffffff;
146         dqopt->info[type].dqi_igrace = dqblk.dqb_itime ? dqblk.dqb_itime : MAX_IQ_TIME;
147         dqopt->info[type].dqi_bgrace = dqblk.dqb_btime ? dqblk.dqb_btime : MAX_DQ_TIME;
148 out:
149         return ret;
150 }
151
152 static int v1_write_file_info(struct super_block *sb, int type)
153 {
154         struct quota_info *dqopt = sb_dqopt(sb);
155         struct v1_disk_dqblk dqblk;
156         int ret;
157
158         dqopt->info[type].dqi_flags &= ~DQF_INFO_DIRTY;
159         if ((ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
160             sizeof(struct v1_disk_dqblk), v1_dqoff(0))) != sizeof(struct v1_disk_dqblk)) {
161                 if (ret >= 0)
162                         ret = -EIO;
163                 goto out;
164         }
165         dqblk.dqb_itime = dqopt->info[type].dqi_igrace;
166         dqblk.dqb_btime = dqopt->info[type].dqi_bgrace;
167         ret = sb->s_op->quota_write(sb, type, (char *)&dqblk,
168               sizeof(struct v1_disk_dqblk), v1_dqoff(0));
169         if (ret == sizeof(struct v1_disk_dqblk))
170                 ret = 0;
171         else if (ret > 0)
172                 ret = -EIO;
173 out:
174         return ret;
175 }
176
177 static struct quota_format_ops v1_format_ops = {
178         .check_quota_file       = v1_check_quota_file,
179         .read_file_info         = v1_read_file_info,
180         .write_file_info        = v1_write_file_info,
181         .free_file_info         = NULL,
182         .read_dqblk             = v1_read_dqblk,
183         .commit_dqblk           = v1_commit_dqblk,
184 };
185
186 static struct quota_format_type v1_quota_format = {
187         .qf_fmt_id      = QFMT_VFS_OLD,
188         .qf_ops         = &v1_format_ops,
189         .qf_owner       = THIS_MODULE
190 };
191
192 static int __init init_v1_quota_format(void)
193 {
194         return register_quota_format(&v1_quota_format);
195 }
196
197 static void __exit exit_v1_quota_format(void)
198 {
199         unregister_quota_format(&v1_quota_format);
200 }
201
202 module_init(init_v1_quota_format);
203 module_exit(exit_v1_quota_format);
204