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
v2_stoqb(qsize_t space)48 static inline qsize_t v2_stoqb(qsize_t space)
49 {
50 return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
51 }
52
v2_qbtos(qsize_t blocks)53 static inline qsize_t v2_qbtos(qsize_t blocks)
54 {
55 return blocks << QUOTABLOCK_BITS;
56 }
57
v2_read_header(struct super_block * sb,int type,struct v2_disk_dqheader * dqhead)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 quota_error(sb, "Failed header read: expected=%zd got=%zd",
67 sizeof(struct v2_disk_dqheader), size);
68 return 0;
69 }
70 return 1;
71 }
72
73 /* Check whether given file is really vfsv0 quotafile */
v2_check_quota_file(struct super_block * sb,int type)74 static int v2_check_quota_file(struct super_block *sb, int type)
75 {
76 struct v2_disk_dqheader dqhead;
77 static const uint quota_magics[] = V2_INITQMAGICS;
78 static const uint quota_versions[] = V2_INITQVERSIONS;
79
80 if (!v2_read_header(sb, type, &dqhead))
81 return 0;
82 if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] ||
83 le32_to_cpu(dqhead.dqh_version) > quota_versions[type])
84 return 0;
85 return 1;
86 }
87
88 /* Read information header from quota file */
v2_read_file_info(struct super_block * sb,int type)89 static int v2_read_file_info(struct super_block *sb, int type)
90 {
91 struct v2_disk_dqinfo dinfo;
92 struct v2_disk_dqheader dqhead;
93 struct mem_dqinfo *info = sb_dqinfo(sb, type);
94 struct qtree_mem_dqinfo *qinfo;
95 ssize_t size;
96 unsigned int version;
97
98 if (!v2_read_header(sb, type, &dqhead))
99 return -1;
100 version = le32_to_cpu(dqhead.dqh_version);
101 if ((info->dqi_fmt_id == QFMT_VFS_V0 && version != 0) ||
102 (info->dqi_fmt_id == QFMT_VFS_V1 && version != 1))
103 return -1;
104
105 size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
106 sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
107 if (size != sizeof(struct v2_disk_dqinfo)) {
108 quota_error(sb, "Can't read info structure");
109 return -1;
110 }
111 info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
112 if (!info->dqi_priv) {
113 printk(KERN_WARNING
114 "Not enough memory for quota information structure.\n");
115 return -ENOMEM;
116 }
117 qinfo = info->dqi_priv;
118 if (version == 0) {
119 /* limits are stored as unsigned 32-bit data */
120 info->dqi_max_spc_limit = 0xffffffffLL << QUOTABLOCK_BITS;
121 info->dqi_max_ino_limit = 0xffffffff;
122 } else {
123 /*
124 * Used space is stored as unsigned 64-bit value in bytes but
125 * quota core supports only signed 64-bit values so use that
126 * as a limit
127 */
128 info->dqi_max_spc_limit = 0x7fffffffffffffffLL; /* 2^63-1 */
129 info->dqi_max_ino_limit = 0x7fffffffffffffffLL;
130 }
131 info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
132 info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
133 /* No flags currently supported */
134 info->dqi_flags = 0;
135 qinfo->dqi_sb = sb;
136 qinfo->dqi_type = type;
137 qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
138 qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
139 qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
140 qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
141 qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
142 qinfo->dqi_qtree_depth = qtree_depth(qinfo);
143 if (version == 0) {
144 qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
145 qinfo->dqi_ops = &v2r0_qtree_ops;
146 } else {
147 qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
148 qinfo->dqi_ops = &v2r1_qtree_ops;
149 }
150 return 0;
151 }
152
153 /* Write information header to quota file */
v2_write_file_info(struct super_block * sb,int type)154 static int v2_write_file_info(struct super_block *sb, int type)
155 {
156 struct v2_disk_dqinfo dinfo;
157 struct mem_dqinfo *info = sb_dqinfo(sb, type);
158 struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
159 ssize_t size;
160
161 spin_lock(&dq_data_lock);
162 info->dqi_flags &= ~DQF_INFO_DIRTY;
163 dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
164 dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
165 /* No flags currently supported */
166 dinfo.dqi_flags = cpu_to_le32(0);
167 spin_unlock(&dq_data_lock);
168 dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
169 dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
170 dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
171 size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
172 sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
173 if (size != sizeof(struct v2_disk_dqinfo)) {
174 quota_error(sb, "Can't write info structure");
175 return -1;
176 }
177 return 0;
178 }
179
v2r0_disk2memdqb(struct dquot * dquot,void * dp)180 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp)
181 {
182 struct v2r0_disk_dqblk *d = dp, empty;
183 struct mem_dqblk *m = &dquot->dq_dqb;
184
185 m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
186 m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
187 m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
188 m->dqb_itime = le64_to_cpu(d->dqb_itime);
189 m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
190 m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
191 m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
192 m->dqb_btime = le64_to_cpu(d->dqb_btime);
193 /* We need to escape back all-zero structure */
194 memset(&empty, 0, sizeof(struct v2r0_disk_dqblk));
195 empty.dqb_itime = cpu_to_le64(1);
196 if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk)))
197 m->dqb_itime = 0;
198 }
199
v2r0_mem2diskdqb(void * dp,struct dquot * dquot)200 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot)
201 {
202 struct v2r0_disk_dqblk *d = dp;
203 struct mem_dqblk *m = &dquot->dq_dqb;
204 struct qtree_mem_dqinfo *info =
205 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
206
207 d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
208 d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
209 d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
210 d->dqb_itime = cpu_to_le64(m->dqb_itime);
211 d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit));
212 d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit));
213 d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
214 d->dqb_btime = cpu_to_le64(m->dqb_btime);
215 d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
216 if (qtree_entry_unused(info, dp))
217 d->dqb_itime = cpu_to_le64(1);
218 }
219
v2r0_is_id(void * dp,struct dquot * dquot)220 static int v2r0_is_id(void *dp, struct dquot *dquot)
221 {
222 struct v2r0_disk_dqblk *d = dp;
223 struct qtree_mem_dqinfo *info =
224 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
225
226 if (qtree_entry_unused(info, dp))
227 return 0;
228 return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
229 le32_to_cpu(d->dqb_id)),
230 dquot->dq_id);
231 }
232
v2r1_disk2memdqb(struct dquot * dquot,void * dp)233 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
234 {
235 struct v2r1_disk_dqblk *d = dp, empty;
236 struct mem_dqblk *m = &dquot->dq_dqb;
237
238 m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
239 m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
240 m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
241 m->dqb_itime = le64_to_cpu(d->dqb_itime);
242 m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
243 m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
244 m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
245 m->dqb_btime = le64_to_cpu(d->dqb_btime);
246 /* We need to escape back all-zero structure */
247 memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
248 empty.dqb_itime = cpu_to_le64(1);
249 if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
250 m->dqb_itime = 0;
251 }
252
v2r1_mem2diskdqb(void * dp,struct dquot * dquot)253 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
254 {
255 struct v2r1_disk_dqblk *d = dp;
256 struct mem_dqblk *m = &dquot->dq_dqb;
257 struct qtree_mem_dqinfo *info =
258 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
259
260 d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
261 d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
262 d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
263 d->dqb_itime = cpu_to_le64(m->dqb_itime);
264 d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
265 d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit));
266 d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
267 d->dqb_btime = cpu_to_le64(m->dqb_btime);
268 d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
269 d->dqb_pad = 0;
270 if (qtree_entry_unused(info, dp))
271 d->dqb_itime = cpu_to_le64(1);
272 }
273
v2r1_is_id(void * dp,struct dquot * dquot)274 static int v2r1_is_id(void *dp, struct dquot *dquot)
275 {
276 struct v2r1_disk_dqblk *d = dp;
277 struct qtree_mem_dqinfo *info =
278 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
279
280 if (qtree_entry_unused(info, dp))
281 return 0;
282 return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
283 le32_to_cpu(d->dqb_id)),
284 dquot->dq_id);
285 }
286
v2_read_dquot(struct dquot * dquot)287 static int v2_read_dquot(struct dquot *dquot)
288 {
289 return qtree_read_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot);
290 }
291
v2_write_dquot(struct dquot * dquot)292 static int v2_write_dquot(struct dquot *dquot)
293 {
294 return qtree_write_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot);
295 }
296
v2_release_dquot(struct dquot * dquot)297 static int v2_release_dquot(struct dquot *dquot)
298 {
299 return qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot);
300 }
301
v2_free_file_info(struct super_block * sb,int type)302 static int v2_free_file_info(struct super_block *sb, int type)
303 {
304 kfree(sb_dqinfo(sb, type)->dqi_priv);
305 return 0;
306 }
307
308 static const struct quota_format_ops v2_format_ops = {
309 .check_quota_file = v2_check_quota_file,
310 .read_file_info = v2_read_file_info,
311 .write_file_info = v2_write_file_info,
312 .free_file_info = v2_free_file_info,
313 .read_dqblk = v2_read_dquot,
314 .commit_dqblk = v2_write_dquot,
315 .release_dqblk = v2_release_dquot,
316 };
317
318 static struct quota_format_type v2r0_quota_format = {
319 .qf_fmt_id = QFMT_VFS_V0,
320 .qf_ops = &v2_format_ops,
321 .qf_owner = THIS_MODULE
322 };
323
324 static struct quota_format_type v2r1_quota_format = {
325 .qf_fmt_id = QFMT_VFS_V1,
326 .qf_ops = &v2_format_ops,
327 .qf_owner = THIS_MODULE
328 };
329
init_v2_quota_format(void)330 static int __init init_v2_quota_format(void)
331 {
332 int ret;
333
334 ret = register_quota_format(&v2r0_quota_format);
335 if (ret)
336 return ret;
337 return register_quota_format(&v2r1_quota_format);
338 }
339
exit_v2_quota_format(void)340 static void __exit exit_v2_quota_format(void)
341 {
342 unregister_quota_format(&v2r0_quota_format);
343 unregister_quota_format(&v2r1_quota_format);
344 }
345
346 module_init(init_v2_quota_format);
347 module_exit(exit_v2_quota_format);
348