xref: /linux/fs/quota/quota_v2.c (revision e0e53dee69e07e9446eb16ceabd55a1116611696)
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 -1;
101 	version = le32_to_cpu(dqhead.dqh_version);
102 	if ((info->dqi_fmt_id == QFMT_VFS_V0 && version != 0) ||
103 	    (info->dqi_fmt_id == QFMT_VFS_V1 && version != 1))
104 		return -1;
105 
106 	size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
107 	       sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
108 	if (size != sizeof(struct v2_disk_dqinfo)) {
109 		printk(KERN_WARNING "quota_v2: Can't read info structure on device %s.\n",
110 			sb->s_id);
111 		return -1;
112 	}
113 	info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
114 	if (!info->dqi_priv) {
115 		printk(KERN_WARNING
116 		       "Not enough memory for quota information structure.\n");
117 		return -1;
118 	}
119 	qinfo = info->dqi_priv;
120 	if (version == 0) {
121 		/* limits are stored as unsigned 32-bit data */
122 		info->dqi_maxblimit = 0xffffffff;
123 		info->dqi_maxilimit = 0xffffffff;
124 	} else {
125 		/* used space is stored as unsigned 64-bit value */
126 		info->dqi_maxblimit = 0xffffffffffffffffULL;	/* 2^64-1 */
127 		info->dqi_maxilimit = 0xffffffffffffffffULL;
128 	}
129 	info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
130 	info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
131 	info->dqi_flags = le32_to_cpu(dinfo.dqi_flags);
132 	qinfo->dqi_sb = sb;
133 	qinfo->dqi_type = type;
134 	qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
135 	qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
136 	qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
137 	qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
138 	qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
139 	qinfo->dqi_qtree_depth = qtree_depth(qinfo);
140 	if (version == 0) {
141 		qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
142 		qinfo->dqi_ops = &v2r0_qtree_ops;
143 	} else {
144 		qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
145 		qinfo->dqi_ops = &v2r1_qtree_ops;
146 	}
147 	return 0;
148 }
149 
150 /* Write information header to quota file */
151 static int v2_write_file_info(struct super_block *sb, int type)
152 {
153 	struct v2_disk_dqinfo dinfo;
154 	struct mem_dqinfo *info = sb_dqinfo(sb, type);
155 	struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
156 	ssize_t size;
157 
158 	spin_lock(&dq_data_lock);
159 	info->dqi_flags &= ~DQF_INFO_DIRTY;
160 	dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
161 	dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
162 	dinfo.dqi_flags = cpu_to_le32(info->dqi_flags & DQF_MASK);
163 	spin_unlock(&dq_data_lock);
164 	dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
165 	dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
166 	dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
167 	size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
168 	       sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
169 	if (size != sizeof(struct v2_disk_dqinfo)) {
170 		printk(KERN_WARNING "Can't write info structure on device %s.\n",
171 			sb->s_id);
172 		return -1;
173 	}
174 	return 0;
175 }
176 
177 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp)
178 {
179 	struct v2r0_disk_dqblk *d = dp, empty;
180 	struct mem_dqblk *m = &dquot->dq_dqb;
181 
182 	m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
183 	m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
184 	m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
185 	m->dqb_itime = le64_to_cpu(d->dqb_itime);
186 	m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
187 	m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
188 	m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
189 	m->dqb_btime = le64_to_cpu(d->dqb_btime);
190 	/* We need to escape back all-zero structure */
191 	memset(&empty, 0, sizeof(struct v2r0_disk_dqblk));
192 	empty.dqb_itime = cpu_to_le64(1);
193 	if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk)))
194 		m->dqb_itime = 0;
195 }
196 
197 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot)
198 {
199 	struct v2r0_disk_dqblk *d = dp;
200 	struct mem_dqblk *m = &dquot->dq_dqb;
201 	struct qtree_mem_dqinfo *info =
202 			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
203 
204 	d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
205 	d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
206 	d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
207 	d->dqb_itime = cpu_to_le64(m->dqb_itime);
208 	d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit));
209 	d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit));
210 	d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
211 	d->dqb_btime = cpu_to_le64(m->dqb_btime);
212 	d->dqb_id = cpu_to_le32(dquot->dq_id);
213 	if (qtree_entry_unused(info, dp))
214 		d->dqb_itime = cpu_to_le64(1);
215 }
216 
217 static int v2r0_is_id(void *dp, struct dquot *dquot)
218 {
219 	struct v2r0_disk_dqblk *d = dp;
220 	struct qtree_mem_dqinfo *info =
221 			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
222 
223 	if (qtree_entry_unused(info, dp))
224 		return 0;
225 	return le32_to_cpu(d->dqb_id) == dquot->dq_id;
226 }
227 
228 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
229 {
230 	struct v2r1_disk_dqblk *d = dp, empty;
231 	struct mem_dqblk *m = &dquot->dq_dqb;
232 
233 	m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
234 	m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
235 	m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
236 	m->dqb_itime = le64_to_cpu(d->dqb_itime);
237 	m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
238 	m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
239 	m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
240 	m->dqb_btime = le64_to_cpu(d->dqb_btime);
241 	/* We need to escape back all-zero structure */
242 	memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
243 	empty.dqb_itime = cpu_to_le64(1);
244 	if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
245 		m->dqb_itime = 0;
246 }
247 
248 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
249 {
250 	struct v2r1_disk_dqblk *d = dp;
251 	struct mem_dqblk *m = &dquot->dq_dqb;
252 	struct qtree_mem_dqinfo *info =
253 			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
254 
255 	d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
256 	d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
257 	d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
258 	d->dqb_itime = cpu_to_le64(m->dqb_itime);
259 	d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
260 	d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit));
261 	d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
262 	d->dqb_btime = cpu_to_le64(m->dqb_btime);
263 	d->dqb_id = cpu_to_le32(dquot->dq_id);
264 	if (qtree_entry_unused(info, dp))
265 		d->dqb_itime = cpu_to_le64(1);
266 }
267 
268 static int v2r1_is_id(void *dp, struct dquot *dquot)
269 {
270 	struct v2r1_disk_dqblk *d = dp;
271 	struct qtree_mem_dqinfo *info =
272 			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
273 
274 	if (qtree_entry_unused(info, dp))
275 		return 0;
276 	return le32_to_cpu(d->dqb_id) == dquot->dq_id;
277 }
278 
279 static int v2_read_dquot(struct dquot *dquot)
280 {
281 	return qtree_read_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
282 }
283 
284 static int v2_write_dquot(struct dquot *dquot)
285 {
286 	return qtree_write_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
287 }
288 
289 static int v2_release_dquot(struct dquot *dquot)
290 {
291 	return qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
292 }
293 
294 static int v2_free_file_info(struct super_block *sb, int type)
295 {
296 	kfree(sb_dqinfo(sb, type)->dqi_priv);
297 	return 0;
298 }
299 
300 static const struct quota_format_ops v2_format_ops = {
301 	.check_quota_file	= v2_check_quota_file,
302 	.read_file_info		= v2_read_file_info,
303 	.write_file_info	= v2_write_file_info,
304 	.free_file_info		= v2_free_file_info,
305 	.read_dqblk		= v2_read_dquot,
306 	.commit_dqblk		= v2_write_dquot,
307 	.release_dqblk		= v2_release_dquot,
308 };
309 
310 static struct quota_format_type v2r0_quota_format = {
311 	.qf_fmt_id	= QFMT_VFS_V0,
312 	.qf_ops		= &v2_format_ops,
313 	.qf_owner	= THIS_MODULE
314 };
315 
316 static struct quota_format_type v2r1_quota_format = {
317 	.qf_fmt_id	= QFMT_VFS_V1,
318 	.qf_ops		= &v2_format_ops,
319 	.qf_owner	= THIS_MODULE
320 };
321 
322 static int __init init_v2_quota_format(void)
323 {
324 	int ret;
325 
326 	ret = register_quota_format(&v2r0_quota_format);
327 	if (ret)
328 		return ret;
329 	return register_quota_format(&v2r1_quota_format);
330 }
331 
332 static void __exit exit_v2_quota_format(void)
333 {
334 	unregister_quota_format(&v2r0_quota_format);
335 	unregister_quota_format(&v2r1_quota_format);
336 }
337 
338 module_init(init_v2_quota_format);
339 module_exit(exit_v2_quota_format);
340