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