Merge tag 'acpi-5.20-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
[linux-2.6-microblaze.git] / fs / quota / quota_v2.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *      vfsv0 quota IO operations on file
4  */
5
6 #include <linux/errno.h>
7 #include <linux/fs.h>
8 #include <linux/mount.h>
9 #include <linux/dqblk_v2.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/quotaops.h>
15
16 #include <asm/byteorder.h>
17
18 #include "quota_tree.h"
19 #include "quotaio_v2.h"
20
21 MODULE_AUTHOR("Jan Kara");
22 MODULE_DESCRIPTION("Quota format v2 support");
23 MODULE_LICENSE("GPL");
24
25 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot);
26 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp);
27 static int v2r0_is_id(void *dp, struct dquot *dquot);
28 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot);
29 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp);
30 static int v2r1_is_id(void *dp, struct dquot *dquot);
31
32 static const struct qtree_fmt_operations v2r0_qtree_ops = {
33         .mem2disk_dqblk = v2r0_mem2diskdqb,
34         .disk2mem_dqblk = v2r0_disk2memdqb,
35         .is_id = v2r0_is_id,
36 };
37
38 static const struct qtree_fmt_operations v2r1_qtree_ops = {
39         .mem2disk_dqblk = v2r1_mem2diskdqb,
40         .disk2mem_dqblk = v2r1_disk2memdqb,
41         .is_id = v2r1_is_id,
42 };
43
44 #define QUOTABLOCK_BITS 10
45 #define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
46
47 static inline qsize_t v2_stoqb(qsize_t space)
48 {
49         return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
50 }
51
52 static inline qsize_t v2_qbtos(qsize_t blocks)
53 {
54         return blocks << QUOTABLOCK_BITS;
55 }
56
57 static int v2_read_header(struct super_block *sb, int type,
58                           struct v2_disk_dqheader *dqhead)
59 {
60         ssize_t size;
61
62         size = sb->s_op->quota_read(sb, type, (char *)dqhead,
63                                     sizeof(struct v2_disk_dqheader), 0);
64         if (size != sizeof(struct v2_disk_dqheader)) {
65                 quota_error(sb, "Failed header read: expected=%zd got=%zd",
66                             sizeof(struct v2_disk_dqheader), size);
67                 if (size < 0)
68                         return size;
69                 return -EIO;
70         }
71         return 0;
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 quota_info *dqopt = sb_dqopt(sb);
95         struct mem_dqinfo *info = &dqopt->info[type];
96         struct qtree_mem_dqinfo *qinfo;
97         ssize_t size;
98         unsigned int version;
99         int ret;
100
101         down_read(&dqopt->dqio_sem);
102         ret = v2_read_header(sb, type, &dqhead);
103         if (ret < 0)
104                 goto out;
105         version = le32_to_cpu(dqhead.dqh_version);
106         if ((info->dqi_fmt_id == QFMT_VFS_V0 && version != 0) ||
107             (info->dqi_fmt_id == QFMT_VFS_V1 && version != 1)) {
108                 ret = -EINVAL;
109                 goto out;
110         }
111
112         size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
113                sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
114         if (size != sizeof(struct v2_disk_dqinfo)) {
115                 quota_error(sb, "Can't read info structure");
116                 if (size < 0)
117                         ret = size;
118                 else
119                         ret = -EIO;
120                 goto out;
121         }
122         info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
123         if (!info->dqi_priv) {
124                 ret = -ENOMEM;
125                 goto out;
126         }
127         qinfo = info->dqi_priv;
128         if (version == 0) {
129                 /* limits are stored as unsigned 32-bit data */
130                 info->dqi_max_spc_limit = 0xffffffffLL << QUOTABLOCK_BITS;
131                 info->dqi_max_ino_limit = 0xffffffff;
132         } else {
133                 /*
134                  * Used space is stored as unsigned 64-bit value in bytes but
135                  * quota core supports only signed 64-bit values so use that
136                  * as a limit
137                  */
138                 info->dqi_max_spc_limit = 0x7fffffffffffffffLL; /* 2^63-1 */
139                 info->dqi_max_ino_limit = 0x7fffffffffffffffLL;
140         }
141         info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
142         info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
143         /* No flags currently supported */
144         info->dqi_flags = 0;
145         qinfo->dqi_sb = sb;
146         qinfo->dqi_type = type;
147         qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
148         qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
149         qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
150         qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
151         qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
152         qinfo->dqi_qtree_depth = qtree_depth(qinfo);
153         if (version == 0) {
154                 qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
155                 qinfo->dqi_ops = &v2r0_qtree_ops;
156         } else {
157                 qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
158                 qinfo->dqi_ops = &v2r1_qtree_ops;
159         }
160         ret = -EUCLEAN;
161         /* Some sanity checks of the read headers... */
162         if ((loff_t)qinfo->dqi_blocks << qinfo->dqi_blocksize_bits >
163             i_size_read(sb_dqopt(sb)->files[type])) {
164                 quota_error(sb, "Number of blocks too big for quota file size (%llu > %llu).",
165                     (loff_t)qinfo->dqi_blocks << qinfo->dqi_blocksize_bits,
166                     i_size_read(sb_dqopt(sb)->files[type]));
167                 goto out_free;
168         }
169         if (qinfo->dqi_free_blk >= qinfo->dqi_blocks) {
170                 quota_error(sb, "Free block number too big (%u >= %u).",
171                             qinfo->dqi_free_blk, qinfo->dqi_blocks);
172                 goto out_free;
173         }
174         if (qinfo->dqi_free_entry >= qinfo->dqi_blocks) {
175                 quota_error(sb, "Block with free entry too big (%u >= %u).",
176                             qinfo->dqi_free_entry, qinfo->dqi_blocks);
177                 goto out_free;
178         }
179         ret = 0;
180 out_free:
181         if (ret) {
182                 kfree(info->dqi_priv);
183                 info->dqi_priv = NULL;
184         }
185 out:
186         up_read(&dqopt->dqio_sem);
187         return ret;
188 }
189
190 /* Write information header to quota file */
191 static int v2_write_file_info(struct super_block *sb, int type)
192 {
193         struct v2_disk_dqinfo dinfo;
194         struct quota_info *dqopt = sb_dqopt(sb);
195         struct mem_dqinfo *info = &dqopt->info[type];
196         struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
197         ssize_t size;
198
199         down_write(&dqopt->dqio_sem);
200         spin_lock(&dq_data_lock);
201         info->dqi_flags &= ~DQF_INFO_DIRTY;
202         dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
203         dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
204         /* No flags currently supported */
205         dinfo.dqi_flags = cpu_to_le32(0);
206         spin_unlock(&dq_data_lock);
207         dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
208         dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
209         dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
210         size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
211                sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
212         up_write(&dqopt->dqio_sem);
213         if (size != sizeof(struct v2_disk_dqinfo)) {
214                 quota_error(sb, "Can't write info structure");
215                 return -1;
216         }
217         return 0;
218 }
219
220 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp)
221 {
222         struct v2r0_disk_dqblk *d = dp, empty;
223         struct mem_dqblk *m = &dquot->dq_dqb;
224
225         m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
226         m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
227         m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
228         m->dqb_itime = le64_to_cpu(d->dqb_itime);
229         m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
230         m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
231         m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
232         m->dqb_btime = le64_to_cpu(d->dqb_btime);
233         /* We need to escape back all-zero structure */
234         memset(&empty, 0, sizeof(struct v2r0_disk_dqblk));
235         empty.dqb_itime = cpu_to_le64(1);
236         if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk)))
237                 m->dqb_itime = 0;
238 }
239
240 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot)
241 {
242         struct v2r0_disk_dqblk *d = dp;
243         struct mem_dqblk *m = &dquot->dq_dqb;
244         struct qtree_mem_dqinfo *info =
245                         sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
246
247         d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
248         d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
249         d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
250         d->dqb_itime = cpu_to_le64(m->dqb_itime);
251         d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit));
252         d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit));
253         d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
254         d->dqb_btime = cpu_to_le64(m->dqb_btime);
255         d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
256         if (qtree_entry_unused(info, dp))
257                 d->dqb_itime = cpu_to_le64(1);
258 }
259
260 static int v2r0_is_id(void *dp, struct dquot *dquot)
261 {
262         struct v2r0_disk_dqblk *d = dp;
263         struct qtree_mem_dqinfo *info =
264                         sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
265
266         if (qtree_entry_unused(info, dp))
267                 return 0;
268         return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
269                                 le32_to_cpu(d->dqb_id)),
270                       dquot->dq_id);
271 }
272
273 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
274 {
275         struct v2r1_disk_dqblk *d = dp, empty;
276         struct mem_dqblk *m = &dquot->dq_dqb;
277
278         m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
279         m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
280         m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
281         m->dqb_itime = le64_to_cpu(d->dqb_itime);
282         m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
283         m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
284         m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
285         m->dqb_btime = le64_to_cpu(d->dqb_btime);
286         /* We need to escape back all-zero structure */
287         memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
288         empty.dqb_itime = cpu_to_le64(1);
289         if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
290                 m->dqb_itime = 0;
291 }
292
293 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
294 {
295         struct v2r1_disk_dqblk *d = dp;
296         struct mem_dqblk *m = &dquot->dq_dqb;
297         struct qtree_mem_dqinfo *info =
298                         sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
299
300         d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
301         d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
302         d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
303         d->dqb_itime = cpu_to_le64(m->dqb_itime);
304         d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
305         d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit));
306         d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
307         d->dqb_btime = cpu_to_le64(m->dqb_btime);
308         d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
309         d->dqb_pad = 0;
310         if (qtree_entry_unused(info, dp))
311                 d->dqb_itime = cpu_to_le64(1);
312 }
313
314 static int v2r1_is_id(void *dp, struct dquot *dquot)
315 {
316         struct v2r1_disk_dqblk *d = dp;
317         struct qtree_mem_dqinfo *info =
318                         sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
319
320         if (qtree_entry_unused(info, dp))
321                 return 0;
322         return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
323                                 le32_to_cpu(d->dqb_id)),
324                       dquot->dq_id);
325 }
326
327 static int v2_read_dquot(struct dquot *dquot)
328 {
329         struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
330         int ret;
331
332         down_read(&dqopt->dqio_sem);
333         ret = qtree_read_dquot(
334                         sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv,
335                         dquot);
336         up_read(&dqopt->dqio_sem);
337         return ret;
338 }
339
340 static int v2_write_dquot(struct dquot *dquot)
341 {
342         struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
343         int ret;
344         bool alloc = false;
345
346         /*
347          * If space for dquot is already allocated, we don't need any
348          * protection as we'll only overwrite the place of dquot. We are
349          * still protected by concurrent writes of the same dquot by
350          * dquot->dq_lock.
351          */
352         if (!dquot->dq_off) {
353                 alloc = true;
354                 down_write(&dqopt->dqio_sem);
355         } else {
356                 down_read(&dqopt->dqio_sem);
357         }
358         ret = qtree_write_dquot(
359                         sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv,
360                         dquot);
361         if (alloc)
362                 up_write(&dqopt->dqio_sem);
363         else
364                 up_read(&dqopt->dqio_sem);
365         return ret;
366 }
367
368 static int v2_release_dquot(struct dquot *dquot)
369 {
370         struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
371         int ret;
372
373         down_write(&dqopt->dqio_sem);
374         ret = qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot);
375         up_write(&dqopt->dqio_sem);
376
377         return ret;
378 }
379
380 static int v2_free_file_info(struct super_block *sb, int type)
381 {
382         kfree(sb_dqinfo(sb, type)->dqi_priv);
383         return 0;
384 }
385
386 static int v2_get_next_id(struct super_block *sb, struct kqid *qid)
387 {
388         struct quota_info *dqopt = sb_dqopt(sb);
389         int ret;
390
391         down_read(&dqopt->dqio_sem);
392         ret = qtree_get_next_id(sb_dqinfo(sb, qid->type)->dqi_priv, qid);
393         up_read(&dqopt->dqio_sem);
394         return ret;
395 }
396
397 static const struct quota_format_ops v2_format_ops = {
398         .check_quota_file       = v2_check_quota_file,
399         .read_file_info         = v2_read_file_info,
400         .write_file_info        = v2_write_file_info,
401         .free_file_info         = v2_free_file_info,
402         .read_dqblk             = v2_read_dquot,
403         .commit_dqblk           = v2_write_dquot,
404         .release_dqblk          = v2_release_dquot,
405         .get_next_id            = v2_get_next_id,
406 };
407
408 static struct quota_format_type v2r0_quota_format = {
409         .qf_fmt_id      = QFMT_VFS_V0,
410         .qf_ops         = &v2_format_ops,
411         .qf_owner       = THIS_MODULE
412 };
413
414 static struct quota_format_type v2r1_quota_format = {
415         .qf_fmt_id      = QFMT_VFS_V1,
416         .qf_ops         = &v2_format_ops,
417         .qf_owner       = THIS_MODULE
418 };
419
420 static int __init init_v2_quota_format(void)
421 {
422         int ret;
423
424         ret = register_quota_format(&v2r0_quota_format);
425         if (ret)
426                 return ret;
427         return register_quota_format(&v2r1_quota_format);
428 }
429
430 static void __exit exit_v2_quota_format(void)
431 {
432         unregister_quota_format(&v2r0_quota_format);
433         unregister_quota_format(&v2r1_quota_format);
434 }
435
436 module_init(init_v2_quota_format);
437 module_exit(exit_v2_quota_format);