1 /* 2 * linux/fs/9p/vfs_inode.c 3 * 4 * This file contains vfs inode ops for the 9P2000 protocol. 5 * 6 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> 7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 11 * as published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to: 20 * Free Software Foundation 21 * 51 Franklin Street, Fifth Floor 22 * Boston, MA 02111-1301 USA 23 * 24 */ 25 26 #include <linux/module.h> 27 #include <linux/errno.h> 28 #include <linux/fs.h> 29 #include <linux/file.h> 30 #include <linux/pagemap.h> 31 #include <linux/stat.h> 32 #include <linux/string.h> 33 #include <linux/inet.h> 34 #include <linux/namei.h> 35 #include <linux/idr.h> 36 #include <linux/sched.h> 37 #include <net/9p/9p.h> 38 #include <net/9p/client.h> 39 40 #include "v9fs.h" 41 #include "v9fs_vfs.h" 42 #include "fid.h" 43 44 static const struct inode_operations v9fs_dir_inode_operations; 45 static const struct inode_operations v9fs_dir_inode_operations_ext; 46 static const struct inode_operations v9fs_file_inode_operations; 47 static const struct inode_operations v9fs_symlink_inode_operations; 48 49 /** 50 * unixmode2p9mode - convert unix mode bits to plan 9 51 * @v9ses: v9fs session information 52 * @mode: mode to convert 53 * 54 */ 55 56 static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode) 57 { 58 int res; 59 res = mode & 0777; 60 if (S_ISDIR(mode)) 61 res |= P9_DMDIR; 62 if (v9fs_extended(v9ses)) { 63 if (S_ISLNK(mode)) 64 res |= P9_DMSYMLINK; 65 if (v9ses->nodev == 0) { 66 if (S_ISSOCK(mode)) 67 res |= P9_DMSOCKET; 68 if (S_ISFIFO(mode)) 69 res |= P9_DMNAMEDPIPE; 70 if (S_ISBLK(mode)) 71 res |= P9_DMDEVICE; 72 if (S_ISCHR(mode)) 73 res |= P9_DMDEVICE; 74 } 75 76 if ((mode & S_ISUID) == S_ISUID) 77 res |= P9_DMSETUID; 78 if ((mode & S_ISGID) == S_ISGID) 79 res |= P9_DMSETGID; 80 if ((mode & S_ISVTX) == S_ISVTX) 81 res |= P9_DMSETVTX; 82 if ((mode & P9_DMLINK)) 83 res |= P9_DMLINK; 84 } 85 86 return res; 87 } 88 89 /** 90 * p9mode2unixmode- convert plan9 mode bits to unix mode bits 91 * @v9ses: v9fs session information 92 * @mode: mode to convert 93 * 94 */ 95 96 static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode) 97 { 98 int res; 99 100 res = mode & 0777; 101 102 if ((mode & P9_DMDIR) == P9_DMDIR) 103 res |= S_IFDIR; 104 else if ((mode & P9_DMSYMLINK) && (v9fs_extended(v9ses))) 105 res |= S_IFLNK; 106 else if ((mode & P9_DMSOCKET) && (v9fs_extended(v9ses)) 107 && (v9ses->nodev == 0)) 108 res |= S_IFSOCK; 109 else if ((mode & P9_DMNAMEDPIPE) && (v9fs_extended(v9ses)) 110 && (v9ses->nodev == 0)) 111 res |= S_IFIFO; 112 else if ((mode & P9_DMDEVICE) && (v9fs_extended(v9ses)) 113 && (v9ses->nodev == 0)) 114 res |= S_IFBLK; 115 else 116 res |= S_IFREG; 117 118 if (v9fs_extended(v9ses)) { 119 if ((mode & P9_DMSETUID) == P9_DMSETUID) 120 res |= S_ISUID; 121 122 if ((mode & P9_DMSETGID) == P9_DMSETGID) 123 res |= S_ISGID; 124 125 if ((mode & P9_DMSETVTX) == P9_DMSETVTX) 126 res |= S_ISVTX; 127 } 128 129 return res; 130 } 131 132 /** 133 * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits 134 * @uflags: flags to convert 135 * @extended: if .u extensions are active 136 */ 137 138 int v9fs_uflags2omode(int uflags, int extended) 139 { 140 int ret; 141 142 ret = 0; 143 switch (uflags&3) { 144 default: 145 case O_RDONLY: 146 ret = P9_OREAD; 147 break; 148 149 case O_WRONLY: 150 ret = P9_OWRITE; 151 break; 152 153 case O_RDWR: 154 ret = P9_ORDWR; 155 break; 156 } 157 158 if (uflags & O_TRUNC) 159 ret |= P9_OTRUNC; 160 161 if (extended) { 162 if (uflags & O_EXCL) 163 ret |= P9_OEXCL; 164 165 if (uflags & O_APPEND) 166 ret |= P9_OAPPEND; 167 } 168 169 return ret; 170 } 171 172 /** 173 * v9fs_blank_wstat - helper function to setup a 9P stat structure 174 * @wstat: structure to initialize 175 * 176 */ 177 178 static void 179 v9fs_blank_wstat(struct p9_wstat *wstat) 180 { 181 wstat->type = ~0; 182 wstat->dev = ~0; 183 wstat->qid.type = ~0; 184 wstat->qid.version = ~0; 185 *((long long *)&wstat->qid.path) = ~0; 186 wstat->mode = ~0; 187 wstat->atime = ~0; 188 wstat->mtime = ~0; 189 wstat->length = ~0; 190 wstat->name = NULL; 191 wstat->uid = NULL; 192 wstat->gid = NULL; 193 wstat->muid = NULL; 194 wstat->n_uid = ~0; 195 wstat->n_gid = ~0; 196 wstat->n_muid = ~0; 197 wstat->extension = NULL; 198 } 199 200 /** 201 * v9fs_get_inode - helper function to setup an inode 202 * @sb: superblock 203 * @mode: mode to setup inode with 204 * 205 */ 206 207 struct inode *v9fs_get_inode(struct super_block *sb, int mode) 208 { 209 int err; 210 struct inode *inode; 211 struct v9fs_session_info *v9ses = sb->s_fs_info; 212 213 P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode); 214 215 inode = new_inode(sb); 216 if (!inode) { 217 P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n"); 218 return ERR_PTR(-ENOMEM); 219 } 220 221 inode->i_mode = mode; 222 inode->i_uid = current_fsuid(); 223 inode->i_gid = current_fsgid(); 224 inode->i_blocks = 0; 225 inode->i_rdev = 0; 226 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; 227 inode->i_mapping->a_ops = &v9fs_addr_operations; 228 229 switch (mode & S_IFMT) { 230 case S_IFIFO: 231 case S_IFBLK: 232 case S_IFCHR: 233 case S_IFSOCK: 234 if (!v9fs_extended(v9ses)) { 235 P9_DPRINTK(P9_DEBUG_ERROR, 236 "special files without extended mode\n"); 237 err = -EINVAL; 238 goto error; 239 } 240 init_special_inode(inode, inode->i_mode, inode->i_rdev); 241 break; 242 case S_IFREG: 243 inode->i_op = &v9fs_file_inode_operations; 244 inode->i_fop = &v9fs_file_operations; 245 break; 246 case S_IFLNK: 247 if (!v9fs_extended(v9ses)) { 248 P9_DPRINTK(P9_DEBUG_ERROR, 249 "extended modes used w/o 9P2000.u\n"); 250 err = -EINVAL; 251 goto error; 252 } 253 inode->i_op = &v9fs_symlink_inode_operations; 254 break; 255 case S_IFDIR: 256 inc_nlink(inode); 257 if (v9fs_extended(v9ses)) 258 inode->i_op = &v9fs_dir_inode_operations_ext; 259 else 260 inode->i_op = &v9fs_dir_inode_operations; 261 inode->i_fop = &v9fs_dir_operations; 262 break; 263 default: 264 P9_DPRINTK(P9_DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n", 265 mode, mode & S_IFMT); 266 err = -EINVAL; 267 goto error; 268 } 269 270 return inode; 271 272 error: 273 iput(inode); 274 return ERR_PTR(err); 275 } 276 277 /* 278 static struct v9fs_fid* 279 v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry) 280 { 281 int err; 282 int nfid; 283 struct v9fs_fid *ret; 284 struct v9fs_fcall *fcall; 285 286 nfid = v9fs_get_idpool(&v9ses->fidpool); 287 if (nfid < 0) { 288 eprintk(KERN_WARNING, "no free fids available\n"); 289 return ERR_PTR(-ENOSPC); 290 } 291 292 err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name, 293 &fcall); 294 295 if (err < 0) { 296 if (fcall && fcall->id == RWALK) 297 goto clunk_fid; 298 299 PRINT_FCALL_ERROR("walk error", fcall); 300 v9fs_put_idpool(nfid, &v9ses->fidpool); 301 goto error; 302 } 303 304 kfree(fcall); 305 fcall = NULL; 306 ret = v9fs_fid_create(v9ses, nfid); 307 if (!ret) { 308 err = -ENOMEM; 309 goto clunk_fid; 310 } 311 312 err = v9fs_fid_insert(ret, dentry); 313 if (err < 0) { 314 v9fs_fid_destroy(ret); 315 goto clunk_fid; 316 } 317 318 return ret; 319 320 clunk_fid: 321 v9fs_t_clunk(v9ses, nfid); 322 323 error: 324 kfree(fcall); 325 return ERR_PTR(err); 326 } 327 */ 328 329 /** 330 * v9fs_inode_from_fid - populate an inode by issuing a attribute request 331 * @v9ses: session information 332 * @fid: fid to issue attribute request for 333 * @sb: superblock on which to create inode 334 * 335 */ 336 337 static struct inode * 338 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, 339 struct super_block *sb) 340 { 341 int err, umode; 342 struct inode *ret; 343 struct p9_wstat *st; 344 345 ret = NULL; 346 st = p9_client_stat(fid); 347 if (IS_ERR(st)) 348 return ERR_CAST(st); 349 350 umode = p9mode2unixmode(v9ses, st->mode); 351 ret = v9fs_get_inode(sb, umode); 352 if (IS_ERR(ret)) { 353 err = PTR_ERR(ret); 354 goto error; 355 } 356 357 v9fs_stat2inode(st, ret, sb); 358 ret->i_ino = v9fs_qid2ino(&st->qid); 359 p9stat_free(st); 360 kfree(st); 361 return ret; 362 363 error: 364 p9stat_free(st); 365 kfree(st); 366 return ERR_PTR(err); 367 } 368 369 /** 370 * v9fs_remove - helper function to remove files and directories 371 * @dir: directory inode that is being deleted 372 * @file: dentry that is being deleted 373 * @rmdir: removing a directory 374 * 375 */ 376 377 static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir) 378 { 379 struct inode *file_inode; 380 struct v9fs_session_info *v9ses; 381 struct p9_fid *v9fid; 382 383 P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file, 384 rmdir); 385 386 file_inode = file->d_inode; 387 v9ses = v9fs_inode2v9ses(file_inode); 388 v9fid = v9fs_fid_clone(file); 389 if (IS_ERR(v9fid)) 390 return PTR_ERR(v9fid); 391 392 return p9_client_remove(v9fid); 393 } 394 395 static int 396 v9fs_open_created(struct inode *inode, struct file *file) 397 { 398 return 0; 399 } 400 401 402 /** 403 * v9fs_create - Create a file 404 * @v9ses: session information 405 * @dir: directory that dentry is being created in 406 * @dentry: dentry that is being created 407 * @extension: 9p2000.u extension string to support devices, etc. 408 * @perm: create permissions 409 * @mode: open mode 410 * 411 */ 412 static struct p9_fid * 413 v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir, 414 struct dentry *dentry, char *extension, u32 perm, u8 mode) 415 { 416 int err; 417 char *name; 418 struct p9_fid *dfid, *ofid, *fid; 419 struct inode *inode; 420 421 P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name); 422 423 err = 0; 424 ofid = NULL; 425 fid = NULL; 426 name = (char *) dentry->d_name.name; 427 dfid = v9fs_fid_clone(dentry->d_parent); 428 if (IS_ERR(dfid)) { 429 err = PTR_ERR(dfid); 430 P9_DPRINTK(P9_DEBUG_VFS, "fid clone failed %d\n", err); 431 dfid = NULL; 432 goto error; 433 } 434 435 /* clone a fid to use for creation */ 436 ofid = p9_client_walk(dfid, 0, NULL, 1); 437 if (IS_ERR(ofid)) { 438 err = PTR_ERR(ofid); 439 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err); 440 ofid = NULL; 441 goto error; 442 } 443 444 err = p9_client_fcreate(ofid, name, perm, mode, extension); 445 if (err < 0) { 446 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err); 447 goto error; 448 } 449 450 /* now walk from the parent so we can get unopened fid */ 451 fid = p9_client_walk(dfid, 1, &name, 0); 452 if (IS_ERR(fid)) { 453 err = PTR_ERR(fid); 454 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err); 455 fid = NULL; 456 goto error; 457 } else 458 dfid = NULL; 459 460 /* instantiate inode and assign the unopened fid to the dentry */ 461 inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb); 462 if (IS_ERR(inode)) { 463 err = PTR_ERR(inode); 464 P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err); 465 goto error; 466 } 467 468 if (v9ses->cache) 469 dentry->d_op = &v9fs_cached_dentry_operations; 470 else 471 dentry->d_op = &v9fs_dentry_operations; 472 473 d_instantiate(dentry, inode); 474 err = v9fs_fid_add(dentry, fid); 475 if (err < 0) 476 goto error; 477 478 return ofid; 479 480 error: 481 if (dfid) 482 p9_client_clunk(dfid); 483 484 if (ofid) 485 p9_client_clunk(ofid); 486 487 if (fid) 488 p9_client_clunk(fid); 489 490 return ERR_PTR(err); 491 } 492 493 /** 494 * v9fs_vfs_create - VFS hook to create files 495 * @dir: directory inode that is being created 496 * @dentry: dentry that is being deleted 497 * @mode: create permissions 498 * @nd: path information 499 * 500 */ 501 502 static int 503 v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode, 504 struct nameidata *nd) 505 { 506 int err; 507 u32 perm; 508 int flags; 509 struct v9fs_session_info *v9ses; 510 struct p9_fid *fid; 511 struct file *filp; 512 513 err = 0; 514 fid = NULL; 515 v9ses = v9fs_inode2v9ses(dir); 516 perm = unixmode2p9mode(v9ses, mode); 517 if (nd && nd->flags & LOOKUP_OPEN) 518 flags = nd->intent.open.flags - 1; 519 else 520 flags = O_RDWR; 521 522 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, 523 v9fs_uflags2omode(flags, v9fs_extended(v9ses))); 524 if (IS_ERR(fid)) { 525 err = PTR_ERR(fid); 526 fid = NULL; 527 goto error; 528 } 529 530 /* if we are opening a file, assign the open fid to the file */ 531 if (nd && nd->flags & LOOKUP_OPEN) { 532 filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created); 533 if (IS_ERR(filp)) { 534 err = PTR_ERR(filp); 535 goto error; 536 } 537 538 filp->private_data = fid; 539 } else 540 p9_client_clunk(fid); 541 542 return 0; 543 544 error: 545 if (fid) 546 p9_client_clunk(fid); 547 548 return err; 549 } 550 551 /** 552 * v9fs_vfs_mkdir - VFS mkdir hook to create a directory 553 * @dir: inode that is being unlinked 554 * @dentry: dentry that is being unlinked 555 * @mode: mode for new directory 556 * 557 */ 558 559 static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) 560 { 561 int err; 562 u32 perm; 563 struct v9fs_session_info *v9ses; 564 struct p9_fid *fid; 565 566 P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name); 567 err = 0; 568 v9ses = v9fs_inode2v9ses(dir); 569 perm = unixmode2p9mode(v9ses, mode | S_IFDIR); 570 fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD); 571 if (IS_ERR(fid)) { 572 err = PTR_ERR(fid); 573 fid = NULL; 574 } 575 576 if (fid) 577 p9_client_clunk(fid); 578 579 return err; 580 } 581 582 /** 583 * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode 584 * @dir: inode that is being walked from 585 * @dentry: dentry that is being walked to? 586 * @nameidata: path data 587 * 588 */ 589 590 static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, 591 struct nameidata *nameidata) 592 { 593 struct super_block *sb; 594 struct v9fs_session_info *v9ses; 595 struct p9_fid *dfid, *fid; 596 struct inode *inode; 597 char *name; 598 int result = 0; 599 600 P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n", 601 dir, dentry->d_name.name, dentry, nameidata); 602 603 sb = dir->i_sb; 604 v9ses = v9fs_inode2v9ses(dir); 605 dfid = v9fs_fid_lookup(dentry->d_parent); 606 if (IS_ERR(dfid)) 607 return ERR_CAST(dfid); 608 609 name = (char *) dentry->d_name.name; 610 fid = p9_client_walk(dfid, 1, &name, 1); 611 if (IS_ERR(fid)) { 612 result = PTR_ERR(fid); 613 if (result == -ENOENT) { 614 d_add(dentry, NULL); 615 return NULL; 616 } 617 618 return ERR_PTR(result); 619 } 620 621 inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb); 622 if (IS_ERR(inode)) { 623 result = PTR_ERR(inode); 624 inode = NULL; 625 goto error; 626 } 627 628 result = v9fs_fid_add(dentry, fid); 629 if (result < 0) 630 goto error; 631 632 if ((fid->qid.version) && (v9ses->cache)) 633 dentry->d_op = &v9fs_cached_dentry_operations; 634 else 635 dentry->d_op = &v9fs_dentry_operations; 636 637 d_add(dentry, inode); 638 return NULL; 639 640 error: 641 p9_client_clunk(fid); 642 643 return ERR_PTR(result); 644 } 645 646 /** 647 * v9fs_vfs_unlink - VFS unlink hook to delete an inode 648 * @i: inode that is being unlinked 649 * @d: dentry that is being unlinked 650 * 651 */ 652 653 static int v9fs_vfs_unlink(struct inode *i, struct dentry *d) 654 { 655 return v9fs_remove(i, d, 0); 656 } 657 658 /** 659 * v9fs_vfs_rmdir - VFS unlink hook to delete a directory 660 * @i: inode that is being unlinked 661 * @d: dentry that is being unlinked 662 * 663 */ 664 665 static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d) 666 { 667 return v9fs_remove(i, d, 1); 668 } 669 670 /** 671 * v9fs_vfs_rename - VFS hook to rename an inode 672 * @old_dir: old dir inode 673 * @old_dentry: old dentry 674 * @new_dir: new dir inode 675 * @new_dentry: new dentry 676 * 677 */ 678 679 static int 680 v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry, 681 struct inode *new_dir, struct dentry *new_dentry) 682 { 683 struct inode *old_inode; 684 struct v9fs_session_info *v9ses; 685 struct p9_fid *oldfid; 686 struct p9_fid *olddirfid; 687 struct p9_fid *newdirfid; 688 struct p9_wstat wstat; 689 int retval; 690 691 P9_DPRINTK(P9_DEBUG_VFS, "\n"); 692 retval = 0; 693 old_inode = old_dentry->d_inode; 694 v9ses = v9fs_inode2v9ses(old_inode); 695 oldfid = v9fs_fid_lookup(old_dentry); 696 if (IS_ERR(oldfid)) 697 return PTR_ERR(oldfid); 698 699 olddirfid = v9fs_fid_clone(old_dentry->d_parent); 700 if (IS_ERR(olddirfid)) { 701 retval = PTR_ERR(olddirfid); 702 goto done; 703 } 704 705 newdirfid = v9fs_fid_clone(new_dentry->d_parent); 706 if (IS_ERR(newdirfid)) { 707 retval = PTR_ERR(newdirfid); 708 goto clunk_olddir; 709 } 710 711 /* 9P can only handle file rename in the same directory */ 712 if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) { 713 P9_DPRINTK(P9_DEBUG_ERROR, 714 "old dir and new dir are different\n"); 715 retval = -EXDEV; 716 goto clunk_newdir; 717 } 718 719 v9fs_blank_wstat(&wstat); 720 wstat.muid = v9ses->uname; 721 wstat.name = (char *) new_dentry->d_name.name; 722 retval = p9_client_wstat(oldfid, &wstat); 723 724 clunk_newdir: 725 p9_client_clunk(newdirfid); 726 727 clunk_olddir: 728 p9_client_clunk(olddirfid); 729 730 done: 731 return retval; 732 } 733 734 /** 735 * v9fs_vfs_getattr - retrieve file metadata 736 * @mnt: mount information 737 * @dentry: file to get attributes on 738 * @stat: metadata structure to populate 739 * 740 */ 741 742 static int 743 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry, 744 struct kstat *stat) 745 { 746 int err; 747 struct v9fs_session_info *v9ses; 748 struct p9_fid *fid; 749 struct p9_wstat *st; 750 751 P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry); 752 err = -EPERM; 753 v9ses = v9fs_inode2v9ses(dentry->d_inode); 754 if (v9ses->cache == CACHE_LOOSE) 755 return simple_getattr(mnt, dentry, stat); 756 757 fid = v9fs_fid_lookup(dentry); 758 if (IS_ERR(fid)) 759 return PTR_ERR(fid); 760 761 st = p9_client_stat(fid); 762 if (IS_ERR(st)) 763 return PTR_ERR(st); 764 765 v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb); 766 generic_fillattr(dentry->d_inode, stat); 767 768 kfree(st); 769 return 0; 770 } 771 772 /** 773 * v9fs_vfs_setattr - set file metadata 774 * @dentry: file whose metadata to set 775 * @iattr: metadata assignment structure 776 * 777 */ 778 779 static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr) 780 { 781 int retval; 782 struct v9fs_session_info *v9ses; 783 struct p9_fid *fid; 784 struct p9_wstat wstat; 785 786 P9_DPRINTK(P9_DEBUG_VFS, "\n"); 787 retval = -EPERM; 788 v9ses = v9fs_inode2v9ses(dentry->d_inode); 789 fid = v9fs_fid_lookup(dentry); 790 if(IS_ERR(fid)) 791 return PTR_ERR(fid); 792 793 v9fs_blank_wstat(&wstat); 794 if (iattr->ia_valid & ATTR_MODE) 795 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode); 796 797 if (iattr->ia_valid & ATTR_MTIME) 798 wstat.mtime = iattr->ia_mtime.tv_sec; 799 800 if (iattr->ia_valid & ATTR_ATIME) 801 wstat.atime = iattr->ia_atime.tv_sec; 802 803 if (iattr->ia_valid & ATTR_SIZE) 804 wstat.length = iattr->ia_size; 805 806 if (v9fs_extended(v9ses)) { 807 if (iattr->ia_valid & ATTR_UID) 808 wstat.n_uid = iattr->ia_uid; 809 810 if (iattr->ia_valid & ATTR_GID) 811 wstat.n_gid = iattr->ia_gid; 812 } 813 814 retval = p9_client_wstat(fid, &wstat); 815 if (retval >= 0) 816 retval = inode_setattr(dentry->d_inode, iattr); 817 818 return retval; 819 } 820 821 /** 822 * v9fs_stat2inode - populate an inode structure with mistat info 823 * @stat: Plan 9 metadata (mistat) structure 824 * @inode: inode to populate 825 * @sb: superblock of filesystem 826 * 827 */ 828 829 void 830 v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode, 831 struct super_block *sb) 832 { 833 char ext[32]; 834 struct v9fs_session_info *v9ses = sb->s_fs_info; 835 836 inode->i_nlink = 1; 837 838 inode->i_atime.tv_sec = stat->atime; 839 inode->i_mtime.tv_sec = stat->mtime; 840 inode->i_ctime.tv_sec = stat->mtime; 841 842 inode->i_uid = v9ses->dfltuid; 843 inode->i_gid = v9ses->dfltgid; 844 845 if (v9fs_extended(v9ses)) { 846 inode->i_uid = stat->n_uid; 847 inode->i_gid = stat->n_gid; 848 } 849 850 inode->i_mode = p9mode2unixmode(v9ses, stat->mode); 851 if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) { 852 char type = 0; 853 int major = -1; 854 int minor = -1; 855 856 strncpy(ext, stat->extension, sizeof(ext)); 857 sscanf(ext, "%c %u %u", &type, &major, &minor); 858 switch (type) { 859 case 'c': 860 inode->i_mode &= ~S_IFBLK; 861 inode->i_mode |= S_IFCHR; 862 break; 863 case 'b': 864 break; 865 default: 866 P9_DPRINTK(P9_DEBUG_ERROR, 867 "Unknown special type %c %s\n", type, 868 stat->extension); 869 }; 870 inode->i_rdev = MKDEV(major, minor); 871 init_special_inode(inode, inode->i_mode, inode->i_rdev); 872 } else 873 inode->i_rdev = 0; 874 875 inode->i_size = stat->length; 876 877 /* not real number of blocks, but 512 byte ones ... */ 878 inode->i_blocks = (inode->i_size + 512 - 1) >> 9; 879 } 880 881 /** 882 * v9fs_qid2ino - convert qid into inode number 883 * @qid: qid to hash 884 * 885 * BUG: potential for inode number collisions? 886 */ 887 888 ino_t v9fs_qid2ino(struct p9_qid *qid) 889 { 890 u64 path = qid->path + 2; 891 ino_t i = 0; 892 893 if (sizeof(ino_t) == sizeof(path)) 894 memcpy(&i, &path, sizeof(ino_t)); 895 else 896 i = (ino_t) (path ^ (path >> 32)); 897 898 return i; 899 } 900 901 /** 902 * v9fs_readlink - read a symlink's location (internal version) 903 * @dentry: dentry for symlink 904 * @buffer: buffer to load symlink location into 905 * @buflen: length of buffer 906 * 907 */ 908 909 static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen) 910 { 911 int retval; 912 913 struct v9fs_session_info *v9ses; 914 struct p9_fid *fid; 915 struct p9_wstat *st; 916 917 P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name); 918 retval = -EPERM; 919 v9ses = v9fs_inode2v9ses(dentry->d_inode); 920 fid = v9fs_fid_lookup(dentry); 921 if (IS_ERR(fid)) 922 return PTR_ERR(fid); 923 924 if (!v9fs_extended(v9ses)) 925 return -EBADF; 926 927 st = p9_client_stat(fid); 928 if (IS_ERR(st)) 929 return PTR_ERR(st); 930 931 if (!(st->mode & P9_DMSYMLINK)) { 932 retval = -EINVAL; 933 goto done; 934 } 935 936 /* copy extension buffer into buffer */ 937 strncpy(buffer, st->extension, buflen); 938 939 P9_DPRINTK(P9_DEBUG_VFS, 940 "%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer); 941 942 retval = buflen; 943 944 done: 945 kfree(st); 946 return retval; 947 } 948 949 /** 950 * v9fs_vfs_readlink - read a symlink's location 951 * @dentry: dentry for symlink 952 * @buffer: buffer to load symlink location into 953 * @buflen: length of buffer 954 * 955 */ 956 957 static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer, 958 int buflen) 959 { 960 int retval; 961 int ret; 962 char *link = __getname(); 963 964 if (unlikely(!link)) 965 return -ENOMEM; 966 967 if (buflen > PATH_MAX) 968 buflen = PATH_MAX; 969 970 P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name, 971 dentry); 972 973 retval = v9fs_readlink(dentry, link, buflen); 974 975 if (retval > 0) { 976 if ((ret = copy_to_user(buffer, link, retval)) != 0) { 977 P9_DPRINTK(P9_DEBUG_ERROR, 978 "problem copying to user: %d\n", ret); 979 retval = ret; 980 } 981 } 982 983 __putname(link); 984 return retval; 985 } 986 987 /** 988 * v9fs_vfs_follow_link - follow a symlink path 989 * @dentry: dentry for symlink 990 * @nd: nameidata 991 * 992 */ 993 994 static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd) 995 { 996 int len = 0; 997 char *link = __getname(); 998 999 P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name); 1000 1001 if (!link) 1002 link = ERR_PTR(-ENOMEM); 1003 else { 1004 len = v9fs_readlink(dentry, link, PATH_MAX); 1005 1006 if (len < 0) { 1007 __putname(link); 1008 link = ERR_PTR(len); 1009 } else 1010 link[len] = 0; 1011 } 1012 nd_set_link(nd, link); 1013 1014 return NULL; 1015 } 1016 1017 /** 1018 * v9fs_vfs_put_link - release a symlink path 1019 * @dentry: dentry for symlink 1020 * @nd: nameidata 1021 * @p: unused 1022 * 1023 */ 1024 1025 static void 1026 v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p) 1027 { 1028 char *s = nd_get_link(nd); 1029 1030 P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name, 1031 IS_ERR(s) ? "<error>" : s); 1032 if (!IS_ERR(s)) 1033 __putname(s); 1034 } 1035 1036 /** 1037 * v9fs_vfs_mkspecial - create a special file 1038 * @dir: inode to create special file in 1039 * @dentry: dentry to create 1040 * @mode: mode to create special file 1041 * @extension: 9p2000.u format extension string representing special file 1042 * 1043 */ 1044 1045 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry, 1046 int mode, const char *extension) 1047 { 1048 u32 perm; 1049 struct v9fs_session_info *v9ses; 1050 struct p9_fid *fid; 1051 1052 v9ses = v9fs_inode2v9ses(dir); 1053 if (!v9fs_extended(v9ses)) { 1054 P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n"); 1055 return -EPERM; 1056 } 1057 1058 perm = unixmode2p9mode(v9ses, mode); 1059 fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm, 1060 P9_OREAD); 1061 if (IS_ERR(fid)) 1062 return PTR_ERR(fid); 1063 1064 p9_client_clunk(fid); 1065 return 0; 1066 } 1067 1068 /** 1069 * v9fs_vfs_symlink - helper function to create symlinks 1070 * @dir: directory inode containing symlink 1071 * @dentry: dentry for symlink 1072 * @symname: symlink data 1073 * 1074 * See Also: 9P2000.u RFC for more information 1075 * 1076 */ 1077 1078 static int 1079 v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) 1080 { 1081 P9_DPRINTK(P9_DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, 1082 dentry->d_name.name, symname); 1083 1084 return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname); 1085 } 1086 1087 /** 1088 * v9fs_vfs_link - create a hardlink 1089 * @old_dentry: dentry for file to link to 1090 * @dir: inode destination for new link 1091 * @dentry: dentry for link 1092 * 1093 */ 1094 1095 static int 1096 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir, 1097 struct dentry *dentry) 1098 { 1099 int retval; 1100 struct p9_fid *oldfid; 1101 char *name; 1102 1103 P9_DPRINTK(P9_DEBUG_VFS, 1104 " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name, 1105 old_dentry->d_name.name); 1106 1107 oldfid = v9fs_fid_clone(old_dentry); 1108 if (IS_ERR(oldfid)) 1109 return PTR_ERR(oldfid); 1110 1111 name = __getname(); 1112 if (unlikely(!name)) { 1113 retval = -ENOMEM; 1114 goto clunk_fid; 1115 } 1116 1117 sprintf(name, "%d\n", oldfid->fid); 1118 retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name); 1119 __putname(name); 1120 1121 clunk_fid: 1122 p9_client_clunk(oldfid); 1123 return retval; 1124 } 1125 1126 /** 1127 * v9fs_vfs_mknod - create a special file 1128 * @dir: inode destination for new link 1129 * @dentry: dentry for file 1130 * @mode: mode for creation 1131 * @rdev: device associated with special file 1132 * 1133 */ 1134 1135 static int 1136 v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev) 1137 { 1138 int retval; 1139 char *name; 1140 1141 P9_DPRINTK(P9_DEBUG_VFS, 1142 " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino, 1143 dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev)); 1144 1145 if (!new_valid_dev(rdev)) 1146 return -EINVAL; 1147 1148 name = __getname(); 1149 if (!name) 1150 return -ENOMEM; 1151 /* build extension */ 1152 if (S_ISBLK(mode)) 1153 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev)); 1154 else if (S_ISCHR(mode)) 1155 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev)); 1156 else if (S_ISFIFO(mode)) 1157 *name = 0; 1158 else { 1159 __putname(name); 1160 return -EINVAL; 1161 } 1162 1163 retval = v9fs_vfs_mkspecial(dir, dentry, mode, name); 1164 __putname(name); 1165 1166 return retval; 1167 } 1168 1169 static const struct inode_operations v9fs_dir_inode_operations_ext = { 1170 .create = v9fs_vfs_create, 1171 .lookup = v9fs_vfs_lookup, 1172 .symlink = v9fs_vfs_symlink, 1173 .link = v9fs_vfs_link, 1174 .unlink = v9fs_vfs_unlink, 1175 .mkdir = v9fs_vfs_mkdir, 1176 .rmdir = v9fs_vfs_rmdir, 1177 .mknod = v9fs_vfs_mknod, 1178 .rename = v9fs_vfs_rename, 1179 .readlink = v9fs_vfs_readlink, 1180 .getattr = v9fs_vfs_getattr, 1181 .setattr = v9fs_vfs_setattr, 1182 }; 1183 1184 static const struct inode_operations v9fs_dir_inode_operations = { 1185 .create = v9fs_vfs_create, 1186 .lookup = v9fs_vfs_lookup, 1187 .unlink = v9fs_vfs_unlink, 1188 .mkdir = v9fs_vfs_mkdir, 1189 .rmdir = v9fs_vfs_rmdir, 1190 .mknod = v9fs_vfs_mknod, 1191 .rename = v9fs_vfs_rename, 1192 .getattr = v9fs_vfs_getattr, 1193 .setattr = v9fs_vfs_setattr, 1194 }; 1195 1196 static const struct inode_operations v9fs_file_inode_operations = { 1197 .getattr = v9fs_vfs_getattr, 1198 .setattr = v9fs_vfs_setattr, 1199 }; 1200 1201 static const struct inode_operations v9fs_symlink_inode_operations = { 1202 .readlink = v9fs_vfs_readlink, 1203 .follow_link = v9fs_vfs_follow_link, 1204 .put_link = v9fs_vfs_put_link, 1205 .getattr = v9fs_vfs_getattr, 1206 .setattr = v9fs_vfs_setattr, 1207 }; 1208