1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/ceph/ceph_debug.h> 3 4 #include <linux/exportfs.h> 5 #include <linux/slab.h> 6 #include <asm/unaligned.h> 7 8 #include "super.h" 9 #include "mds_client.h" 10 #include "crypto.h" 11 12 /* 13 * Basic fh 14 */ 15 struct ceph_nfs_fh { 16 u64 ino; 17 } __attribute__ ((packed)); 18 19 /* 20 * Larger fh that includes parent ino. 21 */ 22 struct ceph_nfs_confh { 23 u64 ino, parent_ino; 24 } __attribute__ ((packed)); 25 26 /* 27 * fh for snapped inode 28 */ 29 struct ceph_nfs_snapfh { 30 u64 ino; 31 u64 snapid; 32 u64 parent_ino; 33 u32 hash; 34 } __attribute__ ((packed)); 35 36 static int ceph_encode_snapfh(struct inode *inode, u32 *rawfh, int *max_len, 37 struct inode *parent_inode) 38 { 39 struct ceph_client *cl = ceph_inode_to_client(inode); 40 static const int snap_handle_length = 41 sizeof(struct ceph_nfs_snapfh) >> 2; 42 struct ceph_nfs_snapfh *sfh = (void *)rawfh; 43 u64 snapid = ceph_snap(inode); 44 int ret; 45 bool no_parent = true; 46 47 if (*max_len < snap_handle_length) { 48 *max_len = snap_handle_length; 49 ret = FILEID_INVALID; 50 goto out; 51 } 52 53 ret = -EINVAL; 54 if (snapid != CEPH_SNAPDIR) { 55 struct inode *dir; 56 struct dentry *dentry = d_find_alias(inode); 57 if (!dentry) 58 goto out; 59 60 rcu_read_lock(); 61 dir = d_inode_rcu(dentry->d_parent); 62 if (ceph_snap(dir) != CEPH_SNAPDIR) { 63 sfh->parent_ino = ceph_ino(dir); 64 sfh->hash = ceph_dentry_hash(dir, dentry); 65 no_parent = false; 66 } 67 rcu_read_unlock(); 68 dput(dentry); 69 } 70 71 if (no_parent) { 72 if (!S_ISDIR(inode->i_mode)) 73 goto out; 74 sfh->parent_ino = sfh->ino; 75 sfh->hash = 0; 76 } 77 sfh->ino = ceph_ino(inode); 78 sfh->snapid = snapid; 79 80 *max_len = snap_handle_length; 81 ret = FILEID_BTRFS_WITH_PARENT; 82 out: 83 doutc(cl, "%p %llx.%llx ret=%d\n", inode, ceph_vinop(inode), ret); 84 return ret; 85 } 86 87 static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len, 88 struct inode *parent_inode) 89 { 90 struct ceph_client *cl = ceph_inode_to_client(inode); 91 static const int handle_length = 92 sizeof(struct ceph_nfs_fh) >> 2; 93 static const int connected_handle_length = 94 sizeof(struct ceph_nfs_confh) >> 2; 95 int type; 96 97 if (ceph_snap(inode) != CEPH_NOSNAP) 98 return ceph_encode_snapfh(inode, rawfh, max_len, parent_inode); 99 100 if (parent_inode && (*max_len < connected_handle_length)) { 101 *max_len = connected_handle_length; 102 return FILEID_INVALID; 103 } else if (*max_len < handle_length) { 104 *max_len = handle_length; 105 return FILEID_INVALID; 106 } 107 108 if (parent_inode) { 109 struct ceph_nfs_confh *cfh = (void *)rawfh; 110 doutc(cl, "%p %llx.%llx with parent %p %llx.%llx\n", inode, 111 ceph_vinop(inode), parent_inode, ceph_vinop(parent_inode)); 112 cfh->ino = ceph_ino(inode); 113 cfh->parent_ino = ceph_ino(parent_inode); 114 *max_len = connected_handle_length; 115 type = FILEID_INO32_GEN_PARENT; 116 } else { 117 struct ceph_nfs_fh *fh = (void *)rawfh; 118 doutc(cl, "%p %llx.%llx\n", inode, ceph_vinop(inode)); 119 fh->ino = ceph_ino(inode); 120 *max_len = handle_length; 121 type = FILEID_INO32_GEN; 122 } 123 return type; 124 } 125 126 static struct inode *__lookup_inode(struct super_block *sb, u64 ino) 127 { 128 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb)->mdsc; 129 struct inode *inode; 130 struct ceph_vino vino; 131 int err; 132 133 vino.ino = ino; 134 vino.snap = CEPH_NOSNAP; 135 136 if (ceph_vino_is_reserved(vino)) 137 return ERR_PTR(-ESTALE); 138 139 inode = ceph_find_inode(sb, vino); 140 if (!inode) { 141 struct ceph_mds_request *req; 142 int mask; 143 144 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO, 145 USE_ANY_MDS); 146 if (IS_ERR(req)) 147 return ERR_CAST(req); 148 149 mask = CEPH_STAT_CAP_INODE; 150 if (ceph_security_xattr_wanted(d_inode(sb->s_root))) 151 mask |= CEPH_CAP_XATTR_SHARED; 152 req->r_args.lookupino.mask = cpu_to_le32(mask); 153 154 req->r_ino1 = vino; 155 req->r_num_caps = 1; 156 err = ceph_mdsc_do_request(mdsc, NULL, req); 157 inode = req->r_target_inode; 158 if (inode) 159 ihold(inode); 160 ceph_mdsc_put_request(req); 161 if (!inode) 162 return err < 0 ? ERR_PTR(err) : ERR_PTR(-ESTALE); 163 } else { 164 if (ceph_inode_is_shutdown(inode)) { 165 iput(inode); 166 return ERR_PTR(-ESTALE); 167 } 168 } 169 return inode; 170 } 171 172 struct inode *ceph_lookup_inode(struct super_block *sb, u64 ino) 173 { 174 struct inode *inode = __lookup_inode(sb, ino); 175 if (IS_ERR(inode)) 176 return inode; 177 if (inode->i_nlink == 0) { 178 iput(inode); 179 return ERR_PTR(-ESTALE); 180 } 181 return inode; 182 } 183 184 static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino) 185 { 186 struct inode *inode = __lookup_inode(sb, ino); 187 struct ceph_inode_info *ci = ceph_inode(inode); 188 int err; 189 190 if (IS_ERR(inode)) 191 return ERR_CAST(inode); 192 /* We need LINK caps to reliably check i_nlink */ 193 err = ceph_do_getattr(inode, CEPH_CAP_LINK_SHARED, false); 194 if (err) { 195 iput(inode); 196 return ERR_PTR(err); 197 } 198 /* -ESTALE if inode as been unlinked and no file is open */ 199 if ((inode->i_nlink == 0) && !__ceph_is_file_opened(ci)) { 200 iput(inode); 201 return ERR_PTR(-ESTALE); 202 } 203 return d_obtain_alias(inode); 204 } 205 206 static struct dentry *__snapfh_to_dentry(struct super_block *sb, 207 struct ceph_nfs_snapfh *sfh, 208 bool want_parent) 209 { 210 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb)->mdsc; 211 struct ceph_client *cl = mdsc->fsc->client; 212 struct ceph_mds_request *req; 213 struct inode *inode; 214 struct ceph_vino vino; 215 int mask; 216 int err; 217 bool unlinked = false; 218 219 if (want_parent) { 220 vino.ino = sfh->parent_ino; 221 if (sfh->snapid == CEPH_SNAPDIR) 222 vino.snap = CEPH_NOSNAP; 223 else if (sfh->ino == sfh->parent_ino) 224 vino.snap = CEPH_SNAPDIR; 225 else 226 vino.snap = sfh->snapid; 227 } else { 228 vino.ino = sfh->ino; 229 vino.snap = sfh->snapid; 230 } 231 232 if (ceph_vino_is_reserved(vino)) 233 return ERR_PTR(-ESTALE); 234 235 inode = ceph_find_inode(sb, vino); 236 if (inode) { 237 if (ceph_inode_is_shutdown(inode)) { 238 iput(inode); 239 return ERR_PTR(-ESTALE); 240 } 241 return d_obtain_alias(inode); 242 } 243 244 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO, 245 USE_ANY_MDS); 246 if (IS_ERR(req)) 247 return ERR_CAST(req); 248 249 mask = CEPH_STAT_CAP_INODE; 250 if (ceph_security_xattr_wanted(d_inode(sb->s_root))) 251 mask |= CEPH_CAP_XATTR_SHARED; 252 req->r_args.lookupino.mask = cpu_to_le32(mask); 253 if (vino.snap < CEPH_NOSNAP) { 254 req->r_args.lookupino.snapid = cpu_to_le64(vino.snap); 255 if (!want_parent && sfh->ino != sfh->parent_ino) { 256 req->r_args.lookupino.parent = 257 cpu_to_le64(sfh->parent_ino); 258 req->r_args.lookupino.hash = 259 cpu_to_le32(sfh->hash); 260 } 261 } 262 263 req->r_ino1 = vino; 264 req->r_num_caps = 1; 265 err = ceph_mdsc_do_request(mdsc, NULL, req); 266 inode = req->r_target_inode; 267 if (inode) { 268 if (vino.snap == CEPH_SNAPDIR) { 269 if (inode->i_nlink == 0) 270 unlinked = true; 271 inode = ceph_get_snapdir(inode); 272 } else if (ceph_snap(inode) == vino.snap) { 273 ihold(inode); 274 } else { 275 /* mds does not support lookup snapped inode */ 276 inode = ERR_PTR(-EOPNOTSUPP); 277 } 278 } else { 279 inode = ERR_PTR(-ESTALE); 280 } 281 ceph_mdsc_put_request(req); 282 283 if (want_parent) { 284 doutc(cl, "%llx.%llx\n err=%d\n", vino.ino, vino.snap, err); 285 } else { 286 doutc(cl, "%llx.%llx parent %llx hash %x err=%d", vino.ino, 287 vino.snap, sfh->parent_ino, sfh->hash, err); 288 } 289 if (IS_ERR(inode)) 290 return ERR_CAST(inode); 291 /* see comments in ceph_get_parent() */ 292 return unlinked ? d_obtain_root(inode) : d_obtain_alias(inode); 293 } 294 295 /* 296 * convert regular fh to dentry 297 */ 298 static struct dentry *ceph_fh_to_dentry(struct super_block *sb, 299 struct fid *fid, 300 int fh_len, int fh_type) 301 { 302 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb); 303 struct ceph_nfs_fh *fh = (void *)fid->raw; 304 305 if (fh_type == FILEID_BTRFS_WITH_PARENT) { 306 struct ceph_nfs_snapfh *sfh = (void *)fid->raw; 307 return __snapfh_to_dentry(sb, sfh, false); 308 } 309 310 if (fh_type != FILEID_INO32_GEN && 311 fh_type != FILEID_INO32_GEN_PARENT) 312 return NULL; 313 if (fh_len < sizeof(*fh) / 4) 314 return NULL; 315 316 doutc(fsc->client, "%llx\n", fh->ino); 317 return __fh_to_dentry(sb, fh->ino); 318 } 319 320 static struct dentry *__get_parent(struct super_block *sb, 321 struct dentry *child, u64 ino) 322 { 323 struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(sb)->mdsc; 324 struct ceph_mds_request *req; 325 struct inode *inode; 326 int mask; 327 int err; 328 329 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT, 330 USE_ANY_MDS); 331 if (IS_ERR(req)) 332 return ERR_CAST(req); 333 334 if (child) { 335 req->r_inode = d_inode(child); 336 ihold(d_inode(child)); 337 } else { 338 req->r_ino1 = (struct ceph_vino) { 339 .ino = ino, 340 .snap = CEPH_NOSNAP, 341 }; 342 } 343 344 mask = CEPH_STAT_CAP_INODE; 345 if (ceph_security_xattr_wanted(d_inode(sb->s_root))) 346 mask |= CEPH_CAP_XATTR_SHARED; 347 req->r_args.getattr.mask = cpu_to_le32(mask); 348 349 req->r_num_caps = 1; 350 err = ceph_mdsc_do_request(mdsc, NULL, req); 351 if (err) { 352 ceph_mdsc_put_request(req); 353 return ERR_PTR(err); 354 } 355 356 inode = req->r_target_inode; 357 if (inode) 358 ihold(inode); 359 ceph_mdsc_put_request(req); 360 if (!inode) 361 return ERR_PTR(-ENOENT); 362 363 return d_obtain_alias(inode); 364 } 365 366 static struct dentry *ceph_get_parent(struct dentry *child) 367 { 368 struct inode *inode = d_inode(child); 369 struct ceph_client *cl = ceph_inode_to_client(inode); 370 struct dentry *dn; 371 372 if (ceph_snap(inode) != CEPH_NOSNAP) { 373 struct inode* dir; 374 bool unlinked = false; 375 /* do not support non-directory */ 376 if (!d_is_dir(child)) { 377 dn = ERR_PTR(-EINVAL); 378 goto out; 379 } 380 dir = __lookup_inode(inode->i_sb, ceph_ino(inode)); 381 if (IS_ERR(dir)) { 382 dn = ERR_CAST(dir); 383 goto out; 384 } 385 /* There can be multiple paths to access snapped inode. 386 * For simplicity, treat snapdir of head inode as parent */ 387 if (ceph_snap(inode) != CEPH_SNAPDIR) { 388 struct inode *snapdir = ceph_get_snapdir(dir); 389 if (dir->i_nlink == 0) 390 unlinked = true; 391 iput(dir); 392 if (IS_ERR(snapdir)) { 393 dn = ERR_CAST(snapdir); 394 goto out; 395 } 396 dir = snapdir; 397 } 398 /* If directory has already been deleted, futher get_parent 399 * will fail. Do not mark snapdir dentry as disconnected, 400 * this prevent exportfs from doing futher get_parent. */ 401 if (unlinked) 402 dn = d_obtain_root(dir); 403 else 404 dn = d_obtain_alias(dir); 405 } else { 406 dn = __get_parent(child->d_sb, child, 0); 407 } 408 out: 409 doutc(cl, "child %p %p %llx.%llx err=%ld\n", child, inode, 410 ceph_vinop(inode), (long)PTR_ERR_OR_ZERO(dn)); 411 return dn; 412 } 413 414 /* 415 * convert regular fh to parent 416 */ 417 static struct dentry *ceph_fh_to_parent(struct super_block *sb, 418 struct fid *fid, 419 int fh_len, int fh_type) 420 { 421 struct ceph_fs_client *fsc = ceph_sb_to_fs_client(sb); 422 struct ceph_nfs_confh *cfh = (void *)fid->raw; 423 struct dentry *dentry; 424 425 if (fh_type == FILEID_BTRFS_WITH_PARENT) { 426 struct ceph_nfs_snapfh *sfh = (void *)fid->raw; 427 return __snapfh_to_dentry(sb, sfh, true); 428 } 429 430 if (fh_type != FILEID_INO32_GEN_PARENT) 431 return NULL; 432 if (fh_len < sizeof(*cfh) / 4) 433 return NULL; 434 435 doutc(fsc->client, "%llx\n", cfh->parent_ino); 436 dentry = __get_parent(sb, NULL, cfh->ino); 437 if (unlikely(dentry == ERR_PTR(-ENOENT))) 438 dentry = __fh_to_dentry(sb, cfh->parent_ino); 439 return dentry; 440 } 441 442 static int __get_snap_name(struct dentry *parent, char *name, 443 struct dentry *child) 444 { 445 struct inode *inode = d_inode(child); 446 struct inode *dir = d_inode(parent); 447 struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode); 448 struct ceph_mds_request *req = NULL; 449 char *last_name = NULL; 450 unsigned next_offset = 2; 451 int err = -EINVAL; 452 453 if (ceph_ino(inode) != ceph_ino(dir)) 454 goto out; 455 if (ceph_snap(inode) == CEPH_SNAPDIR) { 456 if (ceph_snap(dir) == CEPH_NOSNAP) { 457 strcpy(name, fsc->mount_options->snapdir_name); 458 err = 0; 459 } 460 goto out; 461 } 462 if (ceph_snap(dir) != CEPH_SNAPDIR) 463 goto out; 464 465 while (1) { 466 struct ceph_mds_reply_info_parsed *rinfo; 467 struct ceph_mds_reply_dir_entry *rde; 468 int i; 469 470 req = ceph_mdsc_create_request(fsc->mdsc, CEPH_MDS_OP_LSSNAP, 471 USE_AUTH_MDS); 472 if (IS_ERR(req)) { 473 err = PTR_ERR(req); 474 req = NULL; 475 goto out; 476 } 477 err = ceph_alloc_readdir_reply_buffer(req, inode); 478 if (err) 479 goto out; 480 481 req->r_direct_mode = USE_AUTH_MDS; 482 req->r_readdir_offset = next_offset; 483 req->r_args.readdir.flags = 484 cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS); 485 if (last_name) { 486 req->r_path2 = last_name; 487 last_name = NULL; 488 } 489 490 req->r_inode = dir; 491 ihold(dir); 492 req->r_dentry = dget(parent); 493 494 inode_lock(dir); 495 err = ceph_mdsc_do_request(fsc->mdsc, NULL, req); 496 inode_unlock(dir); 497 498 if (err < 0) 499 goto out; 500 501 rinfo = &req->r_reply_info; 502 for (i = 0; i < rinfo->dir_nr; i++) { 503 rde = rinfo->dir_entries + i; 504 BUG_ON(!rde->inode.in); 505 if (ceph_snap(inode) == 506 le64_to_cpu(rde->inode.in->snapid)) { 507 memcpy(name, rde->name, rde->name_len); 508 name[rde->name_len] = '\0'; 509 err = 0; 510 goto out; 511 } 512 } 513 514 if (rinfo->dir_end) 515 break; 516 517 BUG_ON(rinfo->dir_nr <= 0); 518 rde = rinfo->dir_entries + (rinfo->dir_nr - 1); 519 next_offset += rinfo->dir_nr; 520 last_name = kstrndup(rde->name, rde->name_len, GFP_KERNEL); 521 if (!last_name) { 522 err = -ENOMEM; 523 goto out; 524 } 525 526 ceph_mdsc_put_request(req); 527 req = NULL; 528 } 529 err = -ENOENT; 530 out: 531 if (req) 532 ceph_mdsc_put_request(req); 533 kfree(last_name); 534 doutc(fsc->client, "child dentry %p %p %llx.%llx err=%d\n", child, 535 inode, ceph_vinop(inode), err); 536 return err; 537 } 538 539 static int ceph_get_name(struct dentry *parent, char *name, 540 struct dentry *child) 541 { 542 struct ceph_mds_client *mdsc; 543 struct ceph_mds_request *req; 544 struct inode *dir = d_inode(parent); 545 struct inode *inode = d_inode(child); 546 struct ceph_mds_reply_info_parsed *rinfo; 547 int err; 548 549 if (ceph_snap(inode) != CEPH_NOSNAP) 550 return __get_snap_name(parent, name, child); 551 552 mdsc = ceph_inode_to_fs_client(inode)->mdsc; 553 req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME, 554 USE_ANY_MDS); 555 if (IS_ERR(req)) 556 return PTR_ERR(req); 557 558 inode_lock(dir); 559 req->r_inode = inode; 560 ihold(inode); 561 req->r_ino2 = ceph_vino(d_inode(parent)); 562 req->r_parent = dir; 563 ihold(dir); 564 set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); 565 req->r_num_caps = 2; 566 err = ceph_mdsc_do_request(mdsc, NULL, req); 567 inode_unlock(dir); 568 569 if (err) 570 goto out; 571 572 rinfo = &req->r_reply_info; 573 if (!IS_ENCRYPTED(dir)) { 574 memcpy(name, rinfo->dname, rinfo->dname_len); 575 name[rinfo->dname_len] = 0; 576 } else { 577 struct fscrypt_str oname = FSTR_INIT(NULL, 0); 578 struct ceph_fname fname = { .dir = dir, 579 .name = rinfo->dname, 580 .ctext = rinfo->altname, 581 .name_len = rinfo->dname_len, 582 .ctext_len = rinfo->altname_len }; 583 584 err = ceph_fname_alloc_buffer(dir, &oname); 585 if (err < 0) 586 goto out; 587 588 err = ceph_fname_to_usr(&fname, NULL, &oname, NULL); 589 if (!err) { 590 memcpy(name, oname.name, oname.len); 591 name[oname.len] = 0; 592 } 593 ceph_fname_free_buffer(dir, &oname); 594 } 595 out: 596 doutc(mdsc->fsc->client, "child dentry %p %p %llx.%llx err %d %s%s\n", 597 child, inode, ceph_vinop(inode), err, err ? "" : "name ", 598 err ? "" : name); 599 ceph_mdsc_put_request(req); 600 return err; 601 } 602 603 const struct export_operations ceph_export_ops = { 604 .encode_fh = ceph_encode_fh, 605 .fh_to_dentry = ceph_fh_to_dentry, 606 .fh_to_parent = ceph_fh_to_parent, 607 .get_parent = ceph_get_parent, 608 .get_name = ceph_get_name, 609 }; 610