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 const 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 const 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 if (size < 0) 69 return size; 70 return -EIO; 71 } 72 return 0; 73 } 74 75 /* Check whether given file is really vfsv0 quotafile */ 76 static int v2_check_quota_file(struct super_block *sb, int type) 77 { 78 struct v2_disk_dqheader dqhead; 79 static const uint quota_magics[] = V2_INITQMAGICS; 80 static const uint quota_versions[] = V2_INITQVERSIONS; 81 82 if (v2_read_header(sb, type, &dqhead)) 83 return 0; 84 if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] || 85 le32_to_cpu(dqhead.dqh_version) > quota_versions[type]) 86 return 0; 87 return 1; 88 } 89 90 /* Read information header from quota file */ 91 static int v2_read_file_info(struct super_block *sb, int type) 92 { 93 struct v2_disk_dqinfo dinfo; 94 struct v2_disk_dqheader dqhead; 95 struct quota_info *dqopt = sb_dqopt(sb); 96 struct mem_dqinfo *info = &dqopt->info[type]; 97 struct qtree_mem_dqinfo *qinfo; 98 ssize_t size; 99 unsigned int version; 100 int ret; 101 102 down_read(&dqopt->dqio_sem); 103 ret = v2_read_header(sb, type, &dqhead); 104 if (ret < 0) 105 goto out; 106 version = le32_to_cpu(dqhead.dqh_version); 107 if ((info->dqi_fmt_id == QFMT_VFS_V0 && version != 0) || 108 (info->dqi_fmt_id == QFMT_VFS_V1 && version != 1)) { 109 ret = -EINVAL; 110 goto out; 111 } 112 113 size = sb->s_op->quota_read(sb, type, (char *)&dinfo, 114 sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF); 115 if (size != sizeof(struct v2_disk_dqinfo)) { 116 quota_error(sb, "Can't read info structure"); 117 if (size < 0) 118 ret = size; 119 else 120 ret = -EIO; 121 goto out; 122 } 123 info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS); 124 if (!info->dqi_priv) { 125 printk(KERN_WARNING 126 "Not enough memory for quota information structure.\n"); 127 ret = -ENOMEM; 128 goto out; 129 } 130 qinfo = info->dqi_priv; 131 if (version == 0) { 132 /* limits are stored as unsigned 32-bit data */ 133 info->dqi_max_spc_limit = 0xffffffffLL << QUOTABLOCK_BITS; 134 info->dqi_max_ino_limit = 0xffffffff; 135 } else { 136 /* 137 * Used space is stored as unsigned 64-bit value in bytes but 138 * quota core supports only signed 64-bit values so use that 139 * as a limit 140 */ 141 info->dqi_max_spc_limit = 0x7fffffffffffffffLL; /* 2^63-1 */ 142 info->dqi_max_ino_limit = 0x7fffffffffffffffLL; 143 } 144 info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace); 145 info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace); 146 /* No flags currently supported */ 147 info->dqi_flags = 0; 148 qinfo->dqi_sb = sb; 149 qinfo->dqi_type = type; 150 qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks); 151 qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk); 152 qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry); 153 qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS; 154 qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS; 155 qinfo->dqi_qtree_depth = qtree_depth(qinfo); 156 if (version == 0) { 157 qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk); 158 qinfo->dqi_ops = &v2r0_qtree_ops; 159 } else { 160 qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk); 161 qinfo->dqi_ops = &v2r1_qtree_ops; 162 } 163 ret = 0; 164 out: 165 up_read(&dqopt->dqio_sem); 166 return ret; 167 } 168 169 /* Write information header to quota file */ 170 static int v2_write_file_info(struct super_block *sb, int type) 171 { 172 struct v2_disk_dqinfo dinfo; 173 struct quota_info *dqopt = sb_dqopt(sb); 174 struct mem_dqinfo *info = &dqopt->info[type]; 175 struct qtree_mem_dqinfo *qinfo = info->dqi_priv; 176 ssize_t size; 177 178 down_write(&dqopt->dqio_sem); 179 spin_lock(&dq_data_lock); 180 info->dqi_flags &= ~DQF_INFO_DIRTY; 181 dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace); 182 dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace); 183 /* No flags currently supported */ 184 dinfo.dqi_flags = cpu_to_le32(0); 185 spin_unlock(&dq_data_lock); 186 dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks); 187 dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk); 188 dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry); 189 size = sb->s_op->quota_write(sb, type, (char *)&dinfo, 190 sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF); 191 up_write(&dqopt->dqio_sem); 192 if (size != sizeof(struct v2_disk_dqinfo)) { 193 quota_error(sb, "Can't write info structure"); 194 return -1; 195 } 196 return 0; 197 } 198 199 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp) 200 { 201 struct v2r0_disk_dqblk *d = dp, empty; 202 struct mem_dqblk *m = &dquot->dq_dqb; 203 204 m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit); 205 m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit); 206 m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes); 207 m->dqb_itime = le64_to_cpu(d->dqb_itime); 208 m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit)); 209 m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit)); 210 m->dqb_curspace = le64_to_cpu(d->dqb_curspace); 211 m->dqb_btime = le64_to_cpu(d->dqb_btime); 212 /* We need to escape back all-zero structure */ 213 memset(&empty, 0, sizeof(struct v2r0_disk_dqblk)); 214 empty.dqb_itime = cpu_to_le64(1); 215 if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk))) 216 m->dqb_itime = 0; 217 } 218 219 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot) 220 { 221 struct v2r0_disk_dqblk *d = dp; 222 struct mem_dqblk *m = &dquot->dq_dqb; 223 struct qtree_mem_dqinfo *info = 224 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 225 226 d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit); 227 d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit); 228 d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes); 229 d->dqb_itime = cpu_to_le64(m->dqb_itime); 230 d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit)); 231 d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit)); 232 d->dqb_curspace = cpu_to_le64(m->dqb_curspace); 233 d->dqb_btime = cpu_to_le64(m->dqb_btime); 234 d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id)); 235 if (qtree_entry_unused(info, dp)) 236 d->dqb_itime = cpu_to_le64(1); 237 } 238 239 static int v2r0_is_id(void *dp, struct dquot *dquot) 240 { 241 struct v2r0_disk_dqblk *d = dp; 242 struct qtree_mem_dqinfo *info = 243 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 244 245 if (qtree_entry_unused(info, dp)) 246 return 0; 247 return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type, 248 le32_to_cpu(d->dqb_id)), 249 dquot->dq_id); 250 } 251 252 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp) 253 { 254 struct v2r1_disk_dqblk *d = dp, empty; 255 struct mem_dqblk *m = &dquot->dq_dqb; 256 257 m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit); 258 m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit); 259 m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes); 260 m->dqb_itime = le64_to_cpu(d->dqb_itime); 261 m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit)); 262 m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit)); 263 m->dqb_curspace = le64_to_cpu(d->dqb_curspace); 264 m->dqb_btime = le64_to_cpu(d->dqb_btime); 265 /* We need to escape back all-zero structure */ 266 memset(&empty, 0, sizeof(struct v2r1_disk_dqblk)); 267 empty.dqb_itime = cpu_to_le64(1); 268 if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk))) 269 m->dqb_itime = 0; 270 } 271 272 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot) 273 { 274 struct v2r1_disk_dqblk *d = dp; 275 struct mem_dqblk *m = &dquot->dq_dqb; 276 struct qtree_mem_dqinfo *info = 277 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 278 279 d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit); 280 d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit); 281 d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes); 282 d->dqb_itime = cpu_to_le64(m->dqb_itime); 283 d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit)); 284 d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit)); 285 d->dqb_curspace = cpu_to_le64(m->dqb_curspace); 286 d->dqb_btime = cpu_to_le64(m->dqb_btime); 287 d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id)); 288 if (qtree_entry_unused(info, dp)) 289 d->dqb_itime = cpu_to_le64(1); 290 } 291 292 static int v2r1_is_id(void *dp, struct dquot *dquot) 293 { 294 struct v2r1_disk_dqblk *d = dp; 295 struct qtree_mem_dqinfo *info = 296 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 297 298 if (qtree_entry_unused(info, dp)) 299 return 0; 300 return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type, 301 le32_to_cpu(d->dqb_id)), 302 dquot->dq_id); 303 } 304 305 static int v2_read_dquot(struct dquot *dquot) 306 { 307 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 308 int ret; 309 310 down_read(&dqopt->dqio_sem); 311 ret = qtree_read_dquot( 312 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, 313 dquot); 314 up_read(&dqopt->dqio_sem); 315 return ret; 316 } 317 318 static int v2_write_dquot(struct dquot *dquot) 319 { 320 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 321 int ret; 322 bool alloc = false; 323 324 /* 325 * If space for dquot is already allocated, we don't need any 326 * protection as we'll only overwrite the place of dquot. We are 327 * still protected by concurrent writes of the same dquot by 328 * dquot->dq_lock. 329 */ 330 if (!dquot->dq_off) { 331 alloc = true; 332 down_write(&dqopt->dqio_sem); 333 } 334 ret = qtree_write_dquot( 335 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, 336 dquot); 337 if (alloc) 338 up_write(&dqopt->dqio_sem); 339 return ret; 340 } 341 342 static int v2_release_dquot(struct dquot *dquot) 343 { 344 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 345 int ret; 346 347 down_write(&dqopt->dqio_sem); 348 ret = qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot); 349 up_write(&dqopt->dqio_sem); 350 351 return ret; 352 } 353 354 static int v2_free_file_info(struct super_block *sb, int type) 355 { 356 kfree(sb_dqinfo(sb, type)->dqi_priv); 357 return 0; 358 } 359 360 static int v2_get_next_id(struct super_block *sb, struct kqid *qid) 361 { 362 struct quota_info *dqopt = sb_dqopt(sb); 363 int ret; 364 365 down_read(&dqopt->dqio_sem); 366 ret = qtree_get_next_id(sb_dqinfo(sb, qid->type)->dqi_priv, qid); 367 up_read(&dqopt->dqio_sem); 368 return ret; 369 } 370 371 static const struct quota_format_ops v2_format_ops = { 372 .check_quota_file = v2_check_quota_file, 373 .read_file_info = v2_read_file_info, 374 .write_file_info = v2_write_file_info, 375 .free_file_info = v2_free_file_info, 376 .read_dqblk = v2_read_dquot, 377 .commit_dqblk = v2_write_dquot, 378 .release_dqblk = v2_release_dquot, 379 .get_next_id = v2_get_next_id, 380 }; 381 382 static struct quota_format_type v2r0_quota_format = { 383 .qf_fmt_id = QFMT_VFS_V0, 384 .qf_ops = &v2_format_ops, 385 .qf_owner = THIS_MODULE 386 }; 387 388 static struct quota_format_type v2r1_quota_format = { 389 .qf_fmt_id = QFMT_VFS_V1, 390 .qf_ops = &v2_format_ops, 391 .qf_owner = THIS_MODULE 392 }; 393 394 static int __init init_v2_quota_format(void) 395 { 396 int ret; 397 398 ret = register_quota_format(&v2r0_quota_format); 399 if (ret) 400 return ret; 401 return register_quota_format(&v2r1_quota_format); 402 } 403 404 static void __exit exit_v2_quota_format(void) 405 { 406 unregister_quota_format(&v2r0_quota_format); 407 unregister_quota_format(&v2r1_quota_format); 408 } 409 410 module_init(init_v2_quota_format); 411 module_exit(exit_v2_quota_format); 412