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_free_blk <= QT_TREEOFF || 170 qinfo->dqi_free_blk >= qinfo->dqi_blocks)) { 171 quota_error(sb, "Free block number %u out of range (%u, %u).", 172 qinfo->dqi_free_blk, QT_TREEOFF, qinfo->dqi_blocks); 173 goto out_free; 174 } 175 if (qinfo->dqi_free_entry && (qinfo->dqi_free_entry <= QT_TREEOFF || 176 qinfo->dqi_free_entry >= qinfo->dqi_blocks)) { 177 quota_error(sb, "Block with free entry %u out of range (%u, %u).", 178 qinfo->dqi_free_entry, QT_TREEOFF, 179 qinfo->dqi_blocks); 180 goto out_free; 181 } 182 ret = 0; 183 out_free: 184 if (ret) { 185 kfree(info->dqi_priv); 186 info->dqi_priv = NULL; 187 } 188 out: 189 up_read(&dqopt->dqio_sem); 190 return ret; 191 } 192 193 /* Write information header to quota file */ 194 static int v2_write_file_info(struct super_block *sb, int type) 195 { 196 struct v2_disk_dqinfo dinfo; 197 struct quota_info *dqopt = sb_dqopt(sb); 198 struct mem_dqinfo *info = &dqopt->info[type]; 199 struct qtree_mem_dqinfo *qinfo = info->dqi_priv; 200 ssize_t size; 201 202 down_write(&dqopt->dqio_sem); 203 spin_lock(&dq_data_lock); 204 info->dqi_flags &= ~DQF_INFO_DIRTY; 205 dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace); 206 dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace); 207 /* No flags currently supported */ 208 dinfo.dqi_flags = cpu_to_le32(0); 209 spin_unlock(&dq_data_lock); 210 dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks); 211 dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk); 212 dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry); 213 size = sb->s_op->quota_write(sb, type, (char *)&dinfo, 214 sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF); 215 up_write(&dqopt->dqio_sem); 216 if (size != sizeof(struct v2_disk_dqinfo)) { 217 quota_error(sb, "Can't write info structure"); 218 return size < 0 ? size : -EIO; 219 } 220 return 0; 221 } 222 223 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp) 224 { 225 struct v2r0_disk_dqblk *d = dp, empty; 226 struct mem_dqblk *m = &dquot->dq_dqb; 227 228 m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit); 229 m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit); 230 m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes); 231 m->dqb_itime = le64_to_cpu(d->dqb_itime); 232 m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit)); 233 m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit)); 234 m->dqb_curspace = le64_to_cpu(d->dqb_curspace); 235 m->dqb_btime = le64_to_cpu(d->dqb_btime); 236 /* We need to escape back all-zero structure */ 237 memset(&empty, 0, sizeof(struct v2r0_disk_dqblk)); 238 empty.dqb_itime = cpu_to_le64(1); 239 if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk))) 240 m->dqb_itime = 0; 241 } 242 243 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot) 244 { 245 struct v2r0_disk_dqblk *d = dp; 246 struct mem_dqblk *m = &dquot->dq_dqb; 247 struct qtree_mem_dqinfo *info = 248 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 249 250 d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit); 251 d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit); 252 d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes); 253 d->dqb_itime = cpu_to_le64(m->dqb_itime); 254 d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit)); 255 d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit)); 256 d->dqb_curspace = cpu_to_le64(m->dqb_curspace); 257 d->dqb_btime = cpu_to_le64(m->dqb_btime); 258 d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id)); 259 if (qtree_entry_unused(info, dp)) 260 d->dqb_itime = cpu_to_le64(1); 261 } 262 263 static int v2r0_is_id(void *dp, struct dquot *dquot) 264 { 265 struct v2r0_disk_dqblk *d = dp; 266 struct qtree_mem_dqinfo *info = 267 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 268 269 if (qtree_entry_unused(info, dp)) 270 return 0; 271 return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type, 272 le32_to_cpu(d->dqb_id)), 273 dquot->dq_id); 274 } 275 276 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp) 277 { 278 struct v2r1_disk_dqblk *d = dp, empty; 279 struct mem_dqblk *m = &dquot->dq_dqb; 280 281 m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit); 282 m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit); 283 m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes); 284 m->dqb_itime = le64_to_cpu(d->dqb_itime); 285 m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit)); 286 m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit)); 287 m->dqb_curspace = le64_to_cpu(d->dqb_curspace); 288 m->dqb_btime = le64_to_cpu(d->dqb_btime); 289 /* We need to escape back all-zero structure */ 290 memset(&empty, 0, sizeof(struct v2r1_disk_dqblk)); 291 empty.dqb_itime = cpu_to_le64(1); 292 if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk))) 293 m->dqb_itime = 0; 294 } 295 296 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot) 297 { 298 struct v2r1_disk_dqblk *d = dp; 299 struct mem_dqblk *m = &dquot->dq_dqb; 300 struct qtree_mem_dqinfo *info = 301 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 302 303 d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit); 304 d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit); 305 d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes); 306 d->dqb_itime = cpu_to_le64(m->dqb_itime); 307 d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit)); 308 d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit)); 309 d->dqb_curspace = cpu_to_le64(m->dqb_curspace); 310 d->dqb_btime = cpu_to_le64(m->dqb_btime); 311 d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id)); 312 d->dqb_pad = 0; 313 if (qtree_entry_unused(info, dp)) 314 d->dqb_itime = cpu_to_le64(1); 315 } 316 317 static int v2r1_is_id(void *dp, struct dquot *dquot) 318 { 319 struct v2r1_disk_dqblk *d = dp; 320 struct qtree_mem_dqinfo *info = 321 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 322 323 if (qtree_entry_unused(info, dp)) 324 return 0; 325 return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type, 326 le32_to_cpu(d->dqb_id)), 327 dquot->dq_id); 328 } 329 330 static int v2_read_dquot(struct dquot *dquot) 331 { 332 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 333 int ret; 334 335 down_read(&dqopt->dqio_sem); 336 ret = qtree_read_dquot( 337 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, 338 dquot); 339 up_read(&dqopt->dqio_sem); 340 return ret; 341 } 342 343 static int v2_write_dquot(struct dquot *dquot) 344 { 345 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 346 int ret; 347 bool alloc = false; 348 349 /* 350 * If space for dquot is already allocated, we don't need any 351 * protection as we'll only overwrite the place of dquot. We are 352 * still protected by concurrent writes of the same dquot by 353 * dquot->dq_lock. 354 */ 355 if (!dquot->dq_off) { 356 alloc = true; 357 down_write(&dqopt->dqio_sem); 358 } else { 359 down_read(&dqopt->dqio_sem); 360 } 361 ret = qtree_write_dquot( 362 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, 363 dquot); 364 if (alloc) 365 up_write(&dqopt->dqio_sem); 366 else 367 up_read(&dqopt->dqio_sem); 368 return ret; 369 } 370 371 static int v2_release_dquot(struct dquot *dquot) 372 { 373 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 374 int ret; 375 376 down_write(&dqopt->dqio_sem); 377 ret = qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot); 378 up_write(&dqopt->dqio_sem); 379 380 return ret; 381 } 382 383 static int v2_free_file_info(struct super_block *sb, int type) 384 { 385 kfree(sb_dqinfo(sb, type)->dqi_priv); 386 return 0; 387 } 388 389 static int v2_get_next_id(struct super_block *sb, struct kqid *qid) 390 { 391 struct quota_info *dqopt = sb_dqopt(sb); 392 int ret; 393 394 down_read(&dqopt->dqio_sem); 395 ret = qtree_get_next_id(sb_dqinfo(sb, qid->type)->dqi_priv, qid); 396 up_read(&dqopt->dqio_sem); 397 return ret; 398 } 399 400 static const struct quota_format_ops v2_format_ops = { 401 .check_quota_file = v2_check_quota_file, 402 .read_file_info = v2_read_file_info, 403 .write_file_info = v2_write_file_info, 404 .free_file_info = v2_free_file_info, 405 .read_dqblk = v2_read_dquot, 406 .commit_dqblk = v2_write_dquot, 407 .release_dqblk = v2_release_dquot, 408 .get_next_id = v2_get_next_id, 409 }; 410 411 static struct quota_format_type v2r0_quota_format = { 412 .qf_fmt_id = QFMT_VFS_V0, 413 .qf_ops = &v2_format_ops, 414 .qf_owner = THIS_MODULE 415 }; 416 417 static struct quota_format_type v2r1_quota_format = { 418 .qf_fmt_id = QFMT_VFS_V1, 419 .qf_ops = &v2_format_ops, 420 .qf_owner = THIS_MODULE 421 }; 422 423 static int __init init_v2_quota_format(void) 424 { 425 int ret; 426 427 ret = register_quota_format(&v2r0_quota_format); 428 if (ret) 429 return ret; 430 return register_quota_format(&v2r1_quota_format); 431 } 432 433 static void __exit exit_v2_quota_format(void) 434 { 435 unregister_quota_format(&v2r0_quota_format); 436 unregister_quota_format(&v2r1_quota_format); 437 } 438 439 module_init(init_v2_quota_format); 440 module_exit(exit_v2_quota_format); 441