Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux...
[linux-2.6.git] / fs / quota / quota_v2.c
1 /*
2  *      vfsv0 quota IO operations on file
3  */
4
5 #include <linux/errno.h>
6 #include <linux/fs.h>
7 #include <linux/mount.h>
8 #include <linux/dqblk_v2.h>
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/slab.h>
13 #include <linux/quotaops.h>
14
15 #include <asm/byteorder.h>
16
17 #include "quota_tree.h"
18 #include "quotaio_v2.h"
19
20 MODULE_AUTHOR("Jan Kara");
21 MODULE_DESCRIPTION("Quota format v2 support");
22 MODULE_LICENSE("GPL");
23
24 #define __QUOTA_V2_PARANOIA
25
26 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot);
27 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp);
28 static int v2r0_is_id(void *dp, struct dquot *dquot);
29 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot);
30 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp);
31 static int v2r1_is_id(void *dp, struct dquot *dquot);
32
33 static struct qtree_fmt_operations v2r0_qtree_ops = {
34         .mem2disk_dqblk = v2r0_mem2diskdqb,
35         .disk2mem_dqblk = v2r0_disk2memdqb,
36         .is_id = v2r0_is_id,
37 };
38
39 static struct qtree_fmt_operations v2r1_qtree_ops = {
40         .mem2disk_dqblk = v2r1_mem2diskdqb,
41         .disk2mem_dqblk = v2r1_disk2memdqb,
42         .is_id = v2r1_is_id,
43 };
44
45 #define QUOTABLOCK_BITS 10
46 #define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
47
48 static inline qsize_t v2_stoqb(qsize_t space)
49 {
50         return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
51 }
52
53 static inline qsize_t v2_qbtos(qsize_t blocks)
54 {
55         return blocks << QUOTABLOCK_BITS;
56 }
57
58 static int v2_read_header(struct super_block *sb, int type,
59                           struct v2_disk_dqheader *dqhead)
60 {
61         ssize_t size;
62
63         size = sb->s_op->quota_read(sb, type, (char *)dqhead,
64                                     sizeof(struct v2_disk_dqheader), 0);
65         if (size != sizeof(struct v2_disk_dqheader)) {
66                 printk(KERN_WARNING "quota_v2: Failed header read:"
67                        " expected=%zd got=%zd\n",
68                         sizeof(struct v2_disk_dqheader), size);
69                 return 0;
70         }
71         return 1;
72 }
73
74 /* Check whether given file is really vfsv0 quotafile */
75 static int v2_check_quota_file(struct super_block *sb, int type)
76 {
77         struct v2_disk_dqheader dqhead;
78         static const uint quota_magics[] = V2_INITQMAGICS;
79         static const uint quota_versions[] = V2_INITQVERSIONS;
80  
81         if (!v2_read_header(sb, type, &dqhead))
82                 return 0;
83         if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] ||
84             le32_to_cpu(dqhead.dqh_version) > quota_versions[type])
85                 return 0;
86         return 1;
87 }
88
89 /* Read information header from quota file */
90 static int v2_read_file_info(struct super_block *sb, int type)
91 {
92         struct v2_disk_dqinfo dinfo;
93         struct v2_disk_dqheader dqhead;
94         struct mem_dqinfo *info = sb_dqinfo(sb, type);
95         struct qtree_mem_dqinfo *qinfo;
96         ssize_t size;
97         unsigned int version;
98
99         if (!v2_read_header(sb, type, &dqhead))
100                 return 0;
101         version = le32_to_cpu(dqhead.dqh_version);
102
103         size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
104                sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
105         if (size != sizeof(struct v2_disk_dqinfo)) {
106                 printk(KERN_WARNING "quota_v2: Can't read info structure on device %s.\n",
107                         sb->s_id);
108                 return -1;
109         }
110         info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
111         if (!info->dqi_priv) {
112                 printk(KERN_WARNING
113                        "Not enough memory for quota information structure.\n");
114                 return -1;
115         }
116         qinfo = info->dqi_priv;
117         if (version == 0) {
118                 /* limits are stored as unsigned 32-bit data */
119                 info->dqi_maxblimit = 0xffffffff;
120                 info->dqi_maxilimit = 0xffffffff;
121         } else {
122                 /* used space is stored as unsigned 64-bit value */
123                 info->dqi_maxblimit = 0xffffffffffffffff;       /* 2^64-1 */
124                 info->dqi_maxilimit = 0xffffffffffffffff;
125         }
126         info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
127         info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
128         info->dqi_flags = le32_to_cpu(dinfo.dqi_flags);
129         qinfo->dqi_sb = sb;
130         qinfo->dqi_type = type;
131         qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
132         qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
133         qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
134         qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
135         qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
136         qinfo->dqi_qtree_depth = qtree_depth(qinfo);
137         if (version == 0) {
138                 qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
139                 qinfo->dqi_ops = &v2r0_qtree_ops;
140         } else {
141                 qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
142                 qinfo->dqi_ops = &v2r1_qtree_ops;
143         }
144         return 0;
145 }
146
147 /* Write information header to quota file */
148 static int v2_write_file_info(struct super_block *sb, int type)
149 {
150         struct v2_disk_dqinfo dinfo;
151         struct mem_dqinfo *info = sb_dqinfo(sb, type);
152         struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
153         ssize_t size;
154
155         spin_lock(&dq_data_lock);
156         info->dqi_flags &= ~DQF_INFO_DIRTY;
157         dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
158         dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
159         dinfo.dqi_flags = cpu_to_le32(info->dqi_flags & DQF_MASK);
160         spin_unlock(&dq_data_lock);
161         dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
162         dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
163         dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
164         size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
165                sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
166         if (size != sizeof(struct v2_disk_dqinfo)) {
167                 printk(KERN_WARNING "Can't write info structure on device %s.\n",
168                         sb->s_id);
169                 return -1;
170         }
171         return 0;
172 }
173
174 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp)
175 {
176         struct v2r0_disk_dqblk *d = dp, empty;
177         struct mem_dqblk *m = &dquot->dq_dqb;
178
179         m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
180         m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
181         m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
182         m->dqb_itime = le64_to_cpu(d->dqb_itime);
183         m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
184         m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
185         m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
186         m->dqb_btime = le64_to_cpu(d->dqb_btime);
187         /* We need to escape back all-zero structure */
188         memset(&empty, 0, sizeof(struct v2r0_disk_dqblk));
189         empty.dqb_itime = cpu_to_le64(1);
190         if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk)))
191                 m->dqb_itime = 0;
192 }
193
194 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot)
195 {
196         struct v2r0_disk_dqblk *d = dp;
197         struct mem_dqblk *m = &dquot->dq_dqb;
198         struct qtree_mem_dqinfo *info =
199                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
200
201         d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
202         d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
203         d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
204         d->dqb_itime = cpu_to_le64(m->dqb_itime);
205         d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit));
206         d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit));
207         d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
208         d->dqb_btime = cpu_to_le64(m->dqb_btime);
209         d->dqb_id = cpu_to_le32(dquot->dq_id);
210         if (qtree_entry_unused(info, dp))
211                 d->dqb_itime = cpu_to_le64(1);
212 }
213
214 static int v2r0_is_id(void *dp, struct dquot *dquot)
215 {
216         struct v2r0_disk_dqblk *d = dp;
217         struct qtree_mem_dqinfo *info =
218                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
219
220         if (qtree_entry_unused(info, dp))
221                 return 0;
222         return le32_to_cpu(d->dqb_id) == dquot->dq_id;
223 }
224
225 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
226 {
227         struct v2r1_disk_dqblk *d = dp, empty;
228         struct mem_dqblk *m = &dquot->dq_dqb;
229
230         m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
231         m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
232         m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
233         m->dqb_itime = le64_to_cpu(d->dqb_itime);
234         m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
235         m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
236         m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
237         m->dqb_btime = le64_to_cpu(d->dqb_btime);
238         /* We need to escape back all-zero structure */
239         memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
240         empty.dqb_itime = cpu_to_le64(1);
241         if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
242                 m->dqb_itime = 0;
243 }
244
245 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
246 {
247         struct v2r1_disk_dqblk *d = dp;
248         struct mem_dqblk *m = &dquot->dq_dqb;
249         struct qtree_mem_dqinfo *info =
250                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
251
252         d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
253         d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
254         d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
255         d->dqb_itime = cpu_to_le64(m->dqb_itime);
256         d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
257         d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit));
258         d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
259         d->dqb_btime = cpu_to_le64(m->dqb_btime);
260         d->dqb_id = cpu_to_le32(dquot->dq_id);
261         if (qtree_entry_unused(info, dp))
262                 d->dqb_itime = cpu_to_le64(1);
263 }
264
265 static int v2r1_is_id(void *dp, struct dquot *dquot)
266 {
267         struct v2r1_disk_dqblk *d = dp;
268         struct qtree_mem_dqinfo *info =
269                         sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
270
271         if (qtree_entry_unused(info, dp))
272                 return 0;
273         return le32_to_cpu(d->dqb_id) == dquot->dq_id;
274 }
275
276 static int v2_read_dquot(struct dquot *dquot)
277 {
278         return qtree_read_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
279 }
280
281 static int v2_write_dquot(struct dquot *dquot)
282 {
283         return qtree_write_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
284 }
285
286 static int v2_release_dquot(struct dquot *dquot)
287 {
288         return qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
289 }
290
291 static int v2_free_file_info(struct super_block *sb, int type)
292 {
293         kfree(sb_dqinfo(sb, type)->dqi_priv);
294         return 0;
295 }
296
297 static const struct quota_format_ops v2_format_ops = {
298         .check_quota_file       = v2_check_quota_file,
299         .read_file_info         = v2_read_file_info,
300         .write_file_info        = v2_write_file_info,
301         .free_file_info         = v2_free_file_info,
302         .read_dqblk             = v2_read_dquot,
303         .commit_dqblk           = v2_write_dquot,
304         .release_dqblk          = v2_release_dquot,
305 };
306
307 static struct quota_format_type v2r0_quota_format = {
308         .qf_fmt_id      = QFMT_VFS_V0,
309         .qf_ops         = &v2_format_ops,
310         .qf_owner       = THIS_MODULE
311 };
312
313 static struct quota_format_type v2r1_quota_format = {
314         .qf_fmt_id      = QFMT_VFS_V1,
315         .qf_ops         = &v2_format_ops,
316         .qf_owner       = THIS_MODULE
317 };
318
319 static int __init init_v2_quota_format(void)
320 {
321         int ret;
322
323         ret = register_quota_format(&v2r0_quota_format);
324         if (ret)
325                 return ret;
326         return register_quota_format(&v2r1_quota_format);
327 }
328
329 static void __exit exit_v2_quota_format(void)
330 {
331         unregister_quota_format(&v2r0_quota_format);
332         unregister_quota_format(&v2r1_quota_format);
333 }
334
335 module_init(init_v2_quota_format);
336 module_exit(exit_v2_quota_format);