quota: Move quota files into separate directory
[linux-2.6.git] / fs / quota / 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/kernel.h>
7 #include <linux/init.h>
8 #include <linux/module.h>
9
10 #include <asm/byteorder.h>
11
12 #include "quotaio_v1.h"
13
14 MODULE_AUTHOR("Jan Kara");
15 MODULE_DESCRIPTION("Old quota format support");
16 MODULE_LICENSE("GPL");
17
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
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;
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);
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;
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);
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 {
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));
65         dquot->dq_sb->s_op->quota_read(dquot->dq_sb, type, (char *)&dqblk, sizeof(struct v1_disk_dqblk), v1_dqoff(dquot->dq_id));
66
67         v1_disk2mem_dqblk(&dquot->dq_dqb, &dqblk);
68         if (dquot->dq_dqb.dqb_bhardlimit == 0 && dquot->dq_dqb.dqb_bsoftlimit == 0 &&
69             dquot->dq_dqb.dqb_ihardlimit == 0 && dquot->dq_dqb.dqb_isoftlimit == 0)
70                 set_bit(DQ_FAKE_B, &dquot->dq_flags);
71         dqstats.reads++;
72
73         return 0;
74 }
75
76 static int v1_commit_dqblk(struct dquot *dquot)
77 {
78         short type = dquot->dq_type;
79         ssize_t ret;
80         struct v1_disk_dqblk dqblk;
81
82         v1_mem2disk_dqblk(&dqblk, &dquot->dq_dqb);
83         if (dquot->dq_id == 0) {
84                 dqblk.dqb_btime = sb_dqopt(dquot->dq_sb)->info[type].dqi_bgrace;
85                 dqblk.dqb_itime = sb_dqopt(dquot->dq_sb)->info[type].dqi_igrace;
86         }
87         ret = 0;
88         if (sb_dqopt(dquot->dq_sb)->files[type])
89                 ret = dquot->dq_sb->s_op->quota_write(dquot->dq_sb, type, (char *)&dqblk,
90                                         sizeof(struct v1_disk_dqblk), v1_dqoff(dquot->dq_id));
91         if (ret != sizeof(struct v1_disk_dqblk)) {
92                 printk(KERN_WARNING "VFS: dquota write failed on dev %s\n",
93                         dquot->dq_sb->s_id);
94                 if (ret >= 0)
95                         ret = -EIO;
96                 goto out;
97         }
98         ret = 0;
99
100 out:
101         dqstats.writes++;
102
103         return ret;
104 }
105
106 /* Magics of new quota format */
107 #define V2_INITQMAGICS {\
108         0xd9c01f11,     /* USRQUOTA */\
109         0xd9c01927      /* GRPQUOTA */\
110 }
111
112 /* Header of new quota format */
113 struct v2_disk_dqheader {
114         __le32 dqh_magic;        /* Magic number identifying file */
115         __le32 dqh_version;      /* File version */
116 };
117
118 static int v1_check_quota_file(struct super_block *sb, int type)
119 {
120         struct inode *inode = sb_dqopt(sb)->files[type];
121         ulong blocks;
122         size_t off; 
123         struct v2_disk_dqheader dqhead;
124         ssize_t size;
125         loff_t isize;
126         static const uint quota_magics[] = V2_INITQMAGICS;
127
128         isize = i_size_read(inode);
129         if (!isize)
130                 return 0;
131         blocks = isize >> BLOCK_SIZE_BITS;
132         off = isize & (BLOCK_SIZE - 1);
133         if ((blocks % sizeof(struct v1_disk_dqblk) * BLOCK_SIZE + off) % sizeof(struct v1_disk_dqblk))
134                 return 0;
135         /* Doublecheck whether we didn't get file with new format - with old quotactl() this could happen */
136         size = sb->s_op->quota_read(sb, type, (char *)&dqhead, sizeof(struct v2_disk_dqheader), 0);
137         if (size != sizeof(struct v2_disk_dqheader))
138                 return 1;       /* Probably not new format */
139         if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type])
140                 return 1;       /* Definitely not new format */
141         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);
142         return 0;               /* Seems like a new format file -> refuse it */
143 }
144
145 static int v1_read_file_info(struct super_block *sb, int type)
146 {
147         struct quota_info *dqopt = sb_dqopt(sb);
148         struct v1_disk_dqblk dqblk;
149         int ret;
150
151         if ((ret = sb->s_op->quota_read(sb, type, (char *)&dqblk, sizeof(struct v1_disk_dqblk), v1_dqoff(0))) != sizeof(struct v1_disk_dqblk)) {
152                 if (ret >= 0)
153                         ret = -EIO;
154                 goto out;
155         }
156         ret = 0;
157         /* limits are stored as unsigned 32-bit data */
158         dqopt->info[type].dqi_maxblimit = 0xffffffff;
159         dqopt->info[type].dqi_maxilimit = 0xffffffff;
160         dqopt->info[type].dqi_igrace = dqblk.dqb_itime ? dqblk.dqb_itime : MAX_IQ_TIME;
161         dqopt->info[type].dqi_bgrace = dqblk.dqb_btime ? dqblk.dqb_btime : MAX_DQ_TIME;
162 out:
163         return ret;
164 }
165
166 static int v1_write_file_info(struct super_block *sb, int type)
167 {
168         struct quota_info *dqopt = sb_dqopt(sb);
169         struct v1_disk_dqblk dqblk;
170         int ret;
171
172         dqopt->info[type].dqi_flags &= ~DQF_INFO_DIRTY;
173         if ((ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
174             sizeof(struct v1_disk_dqblk), v1_dqoff(0))) != sizeof(struct v1_disk_dqblk)) {
175                 if (ret >= 0)
176                         ret = -EIO;
177                 goto out;
178         }
179         dqblk.dqb_itime = dqopt->info[type].dqi_igrace;
180         dqblk.dqb_btime = dqopt->info[type].dqi_bgrace;
181         ret = sb->s_op->quota_write(sb, type, (char *)&dqblk,
182               sizeof(struct v1_disk_dqblk), v1_dqoff(0));
183         if (ret == sizeof(struct v1_disk_dqblk))
184                 ret = 0;
185         else if (ret > 0)
186                 ret = -EIO;
187 out:
188         return ret;
189 }
190
191 static struct quota_format_ops v1_format_ops = {
192         .check_quota_file       = v1_check_quota_file,
193         .read_file_info         = v1_read_file_info,
194         .write_file_info        = v1_write_file_info,
195         .free_file_info         = NULL,
196         .read_dqblk             = v1_read_dqblk,
197         .commit_dqblk           = v1_commit_dqblk,
198 };
199
200 static struct quota_format_type v1_quota_format = {
201         .qf_fmt_id      = QFMT_VFS_OLD,
202         .qf_ops         = &v1_format_ops,
203         .qf_owner       = THIS_MODULE
204 };
205
206 static int __init init_v1_quota_format(void)
207 {
208         return register_quota_format(&v1_quota_format);
209 }
210
211 static void __exit exit_v1_quota_format(void)
212 {
213         unregister_quota_format(&v1_quota_format);
214 }
215
216 module_init(init_v1_quota_format);
217 module_exit(exit_v1_quota_format);
218