xref: /openbmc/linux/fs/quota/quota_v2.c (revision 588b48ca)
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 		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 */
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 */
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_maxblimit = 0xffffffff;
121 		info->dqi_maxilimit = 0xffffffff;
122 	} else {
123 		/* used space is stored as unsigned 64-bit value */
124 		info->dqi_maxblimit = 0xffffffffffffffffULL;	/* 2^64-1 */
125 		info->dqi_maxilimit = 0xffffffffffffffffULL;
126 	}
127 	info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
128 	info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
129 	info->dqi_flags = le32_to_cpu(dinfo.dqi_flags);
130 	qinfo->dqi_sb = sb;
131 	qinfo->dqi_type = type;
132 	qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
133 	qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
134 	qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
135 	qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
136 	qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
137 	qinfo->dqi_qtree_depth = qtree_depth(qinfo);
138 	if (version == 0) {
139 		qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
140 		qinfo->dqi_ops = &v2r0_qtree_ops;
141 	} else {
142 		qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
143 		qinfo->dqi_ops = &v2r1_qtree_ops;
144 	}
145 	return 0;
146 }
147 
148 /* Write information header to quota file */
149 static int v2_write_file_info(struct super_block *sb, int type)
150 {
151 	struct v2_disk_dqinfo dinfo;
152 	struct mem_dqinfo *info = sb_dqinfo(sb, type);
153 	struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
154 	ssize_t size;
155 
156 	spin_lock(&dq_data_lock);
157 	info->dqi_flags &= ~DQF_INFO_DIRTY;
158 	dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
159 	dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
160 	dinfo.dqi_flags = cpu_to_le32(info->dqi_flags & DQF_MASK);
161 	spin_unlock(&dq_data_lock);
162 	dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
163 	dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
164 	dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
165 	size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
166 	       sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
167 	if (size != sizeof(struct v2_disk_dqinfo)) {
168 		quota_error(sb, "Can't write info structure");
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_id.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(from_kqid(&init_user_ns, 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_id.type)->dqi_priv;
219 
220 	if (qtree_entry_unused(info, dp))
221 		return 0;
222 	return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
223 				le32_to_cpu(d->dqb_id)),
224 		      dquot->dq_id);
225 }
226 
227 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
228 {
229 	struct v2r1_disk_dqblk *d = dp, empty;
230 	struct mem_dqblk *m = &dquot->dq_dqb;
231 
232 	m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
233 	m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
234 	m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
235 	m->dqb_itime = le64_to_cpu(d->dqb_itime);
236 	m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
237 	m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
238 	m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
239 	m->dqb_btime = le64_to_cpu(d->dqb_btime);
240 	/* We need to escape back all-zero structure */
241 	memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
242 	empty.dqb_itime = cpu_to_le64(1);
243 	if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
244 		m->dqb_itime = 0;
245 }
246 
247 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
248 {
249 	struct v2r1_disk_dqblk *d = dp;
250 	struct mem_dqblk *m = &dquot->dq_dqb;
251 	struct qtree_mem_dqinfo *info =
252 			sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
253 
254 	d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
255 	d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
256 	d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
257 	d->dqb_itime = cpu_to_le64(m->dqb_itime);
258 	d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
259 	d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit));
260 	d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
261 	d->dqb_btime = cpu_to_le64(m->dqb_btime);
262 	d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
263 	if (qtree_entry_unused(info, dp))
264 		d->dqb_itime = cpu_to_le64(1);
265 }
266 
267 static int v2r1_is_id(void *dp, struct dquot *dquot)
268 {
269 	struct v2r1_disk_dqblk *d = dp;
270 	struct qtree_mem_dqinfo *info =
271 			sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
272 
273 	if (qtree_entry_unused(info, dp))
274 		return 0;
275 	return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
276 				le32_to_cpu(d->dqb_id)),
277 		      dquot->dq_id);
278 }
279 
280 static int v2_read_dquot(struct dquot *dquot)
281 {
282 	return qtree_read_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot);
283 }
284 
285 static int v2_write_dquot(struct dquot *dquot)
286 {
287 	return qtree_write_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot);
288 }
289 
290 static int v2_release_dquot(struct dquot *dquot)
291 {
292 	return qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot);
293 }
294 
295 static int v2_free_file_info(struct super_block *sb, int type)
296 {
297 	kfree(sb_dqinfo(sb, type)->dqi_priv);
298 	return 0;
299 }
300 
301 static const struct quota_format_ops v2_format_ops = {
302 	.check_quota_file	= v2_check_quota_file,
303 	.read_file_info		= v2_read_file_info,
304 	.write_file_info	= v2_write_file_info,
305 	.free_file_info		= v2_free_file_info,
306 	.read_dqblk		= v2_read_dquot,
307 	.commit_dqblk		= v2_write_dquot,
308 	.release_dqblk		= v2_release_dquot,
309 };
310 
311 static struct quota_format_type v2r0_quota_format = {
312 	.qf_fmt_id	= QFMT_VFS_V0,
313 	.qf_ops		= &v2_format_ops,
314 	.qf_owner	= THIS_MODULE
315 };
316 
317 static struct quota_format_type v2r1_quota_format = {
318 	.qf_fmt_id	= QFMT_VFS_V1,
319 	.qf_ops		= &v2_format_ops,
320 	.qf_owner	= THIS_MODULE
321 };
322 
323 static int __init init_v2_quota_format(void)
324 {
325 	int ret;
326 
327 	ret = register_quota_format(&v2r0_quota_format);
328 	if (ret)
329 		return ret;
330 	return register_quota_format(&v2r1_quota_format);
331 }
332 
333 static void __exit exit_v2_quota_format(void)
334 {
335 	unregister_quota_format(&v2r0_quota_format);
336 	unregister_quota_format(&v2r1_quota_format);
337 }
338 
339 module_init(init_v2_quota_format);
340 module_exit(exit_v2_quota_format);
341