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); 438