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 = 0; 161 out: 162 up_read(&dqopt->dqio_sem); 163 return ret; 164 } 165 166 /* Write information header to quota file */ 167 static int v2_write_file_info(struct super_block *sb, int type) 168 { 169 struct v2_disk_dqinfo dinfo; 170 struct quota_info *dqopt = sb_dqopt(sb); 171 struct mem_dqinfo *info = &dqopt->info[type]; 172 struct qtree_mem_dqinfo *qinfo = info->dqi_priv; 173 ssize_t size; 174 175 down_write(&dqopt->dqio_sem); 176 spin_lock(&dq_data_lock); 177 info->dqi_flags &= ~DQF_INFO_DIRTY; 178 dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace); 179 dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace); 180 /* No flags currently supported */ 181 dinfo.dqi_flags = cpu_to_le32(0); 182 spin_unlock(&dq_data_lock); 183 dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks); 184 dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk); 185 dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry); 186 size = sb->s_op->quota_write(sb, type, (char *)&dinfo, 187 sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF); 188 up_write(&dqopt->dqio_sem); 189 if (size != sizeof(struct v2_disk_dqinfo)) { 190 quota_error(sb, "Can't write info structure"); 191 return -1; 192 } 193 return 0; 194 } 195 196 static void v2r0_disk2memdqb(struct dquot *dquot, void *dp) 197 { 198 struct v2r0_disk_dqblk *d = dp, empty; 199 struct mem_dqblk *m = &dquot->dq_dqb; 200 201 m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit); 202 m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit); 203 m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes); 204 m->dqb_itime = le64_to_cpu(d->dqb_itime); 205 m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit)); 206 m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit)); 207 m->dqb_curspace = le64_to_cpu(d->dqb_curspace); 208 m->dqb_btime = le64_to_cpu(d->dqb_btime); 209 /* We need to escape back all-zero structure */ 210 memset(&empty, 0, sizeof(struct v2r0_disk_dqblk)); 211 empty.dqb_itime = cpu_to_le64(1); 212 if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk))) 213 m->dqb_itime = 0; 214 } 215 216 static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot) 217 { 218 struct v2r0_disk_dqblk *d = dp; 219 struct mem_dqblk *m = &dquot->dq_dqb; 220 struct qtree_mem_dqinfo *info = 221 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 222 223 d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit); 224 d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit); 225 d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes); 226 d->dqb_itime = cpu_to_le64(m->dqb_itime); 227 d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit)); 228 d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit)); 229 d->dqb_curspace = cpu_to_le64(m->dqb_curspace); 230 d->dqb_btime = cpu_to_le64(m->dqb_btime); 231 d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id)); 232 if (qtree_entry_unused(info, dp)) 233 d->dqb_itime = cpu_to_le64(1); 234 } 235 236 static int v2r0_is_id(void *dp, struct dquot *dquot) 237 { 238 struct v2r0_disk_dqblk *d = dp; 239 struct qtree_mem_dqinfo *info = 240 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 241 242 if (qtree_entry_unused(info, dp)) 243 return 0; 244 return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type, 245 le32_to_cpu(d->dqb_id)), 246 dquot->dq_id); 247 } 248 249 static void v2r1_disk2memdqb(struct dquot *dquot, void *dp) 250 { 251 struct v2r1_disk_dqblk *d = dp, empty; 252 struct mem_dqblk *m = &dquot->dq_dqb; 253 254 m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit); 255 m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit); 256 m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes); 257 m->dqb_itime = le64_to_cpu(d->dqb_itime); 258 m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit)); 259 m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit)); 260 m->dqb_curspace = le64_to_cpu(d->dqb_curspace); 261 m->dqb_btime = le64_to_cpu(d->dqb_btime); 262 /* We need to escape back all-zero structure */ 263 memset(&empty, 0, sizeof(struct v2r1_disk_dqblk)); 264 empty.dqb_itime = cpu_to_le64(1); 265 if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk))) 266 m->dqb_itime = 0; 267 } 268 269 static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot) 270 { 271 struct v2r1_disk_dqblk *d = dp; 272 struct mem_dqblk *m = &dquot->dq_dqb; 273 struct qtree_mem_dqinfo *info = 274 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 275 276 d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit); 277 d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit); 278 d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes); 279 d->dqb_itime = cpu_to_le64(m->dqb_itime); 280 d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit)); 281 d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit)); 282 d->dqb_curspace = cpu_to_le64(m->dqb_curspace); 283 d->dqb_btime = cpu_to_le64(m->dqb_btime); 284 d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id)); 285 d->dqb_pad = 0; 286 if (qtree_entry_unused(info, dp)) 287 d->dqb_itime = cpu_to_le64(1); 288 } 289 290 static int v2r1_is_id(void *dp, struct dquot *dquot) 291 { 292 struct v2r1_disk_dqblk *d = dp; 293 struct qtree_mem_dqinfo *info = 294 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv; 295 296 if (qtree_entry_unused(info, dp)) 297 return 0; 298 return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type, 299 le32_to_cpu(d->dqb_id)), 300 dquot->dq_id); 301 } 302 303 static int v2_read_dquot(struct dquot *dquot) 304 { 305 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 306 int ret; 307 308 down_read(&dqopt->dqio_sem); 309 ret = qtree_read_dquot( 310 sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, 311 dquot); 312 up_read(&dqopt->dqio_sem); 313 return ret; 314 } 315 316 static int v2_write_dquot(struct dquot *dquot) 317 { 318 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 319 int ret; 320 bool alloc = false; 321 322 /* 323 * If space for dquot is already allocated, we don't need any 324 * protection as we'll only overwrite the place of dquot. We are 325 * still protected by concurrent writes of the same dquot by 326 * dquot->dq_lock. 327 */ 328 if (!dquot->dq_off) { 329 alloc = true; 330 down_write(&dqopt->dqio_sem); 331 } else { 332 down_read(&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 else 340 up_read(&dqopt->dqio_sem); 341 return ret; 342 } 343 344 static int v2_release_dquot(struct dquot *dquot) 345 { 346 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb); 347 int ret; 348 349 down_write(&dqopt->dqio_sem); 350 ret = qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot); 351 up_write(&dqopt->dqio_sem); 352 353 return ret; 354 } 355 356 static int v2_free_file_info(struct super_block *sb, int type) 357 { 358 kfree(sb_dqinfo(sb, type)->dqi_priv); 359 return 0; 360 } 361 362 static int v2_get_next_id(struct super_block *sb, struct kqid *qid) 363 { 364 struct quota_info *dqopt = sb_dqopt(sb); 365 int ret; 366 367 down_read(&dqopt->dqio_sem); 368 ret = qtree_get_next_id(sb_dqinfo(sb, qid->type)->dqi_priv, qid); 369 up_read(&dqopt->dqio_sem); 370 return ret; 371 } 372 373 static const struct quota_format_ops v2_format_ops = { 374 .check_quota_file = v2_check_quota_file, 375 .read_file_info = v2_read_file_info, 376 .write_file_info = v2_write_file_info, 377 .free_file_info = v2_free_file_info, 378 .read_dqblk = v2_read_dquot, 379 .commit_dqblk = v2_write_dquot, 380 .release_dqblk = v2_release_dquot, 381 .get_next_id = v2_get_next_id, 382 }; 383 384 static struct quota_format_type v2r0_quota_format = { 385 .qf_fmt_id = QFMT_VFS_V0, 386 .qf_ops = &v2_format_ops, 387 .qf_owner = THIS_MODULE 388 }; 389 390 static struct quota_format_type v2r1_quota_format = { 391 .qf_fmt_id = QFMT_VFS_V1, 392 .qf_ops = &v2_format_ops, 393 .qf_owner = THIS_MODULE 394 }; 395 396 static int __init init_v2_quota_format(void) 397 { 398 int ret; 399 400 ret = register_quota_format(&v2r0_quota_format); 401 if (ret) 402 return ret; 403 return register_quota_format(&v2r1_quota_format); 404 } 405 406 static void __exit exit_v2_quota_format(void) 407 { 408 unregister_quota_format(&v2r0_quota_format); 409 unregister_quota_format(&v2r1_quota_format); 410 } 411 412 module_init(init_v2_quota_format); 413 module_exit(exit_v2_quota_format); 414