| 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 2 | /* |
| 3 | * linux/fs/9p/vfs_inode.c |
| 4 | * |
| 5 | * This file contains vfs inode ops for the 9P2000 protocol. |
| 6 | * |
| 7 | * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> |
| 8 | * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> |
| 9 | */ |
| 10 | |
| 11 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 12 | |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/errno.h> |
| 15 | #include <linux/fs.h> |
| 16 | #include <linux/file.h> |
| 17 | #include <linux/pagemap.h> |
| 18 | #include <linux/stat.h> |
| 19 | #include <linux/string.h> |
| 20 | #include <linux/inet.h> |
| 21 | #include <linux/namei.h> |
| 22 | #include <linux/idr.h> |
| 23 | #include <linux/sched.h> |
| 24 | #include <linux/slab.h> |
| 25 | #include <linux/xattr.h> |
| 26 | #include <linux/posix_acl.h> |
| 27 | #include <net/9p/9p.h> |
| 28 | #include <net/9p/client.h> |
| 29 | |
| 30 | #include "v9fs.h" |
| 31 | #include "v9fs_vfs.h" |
| 32 | #include "fid.h" |
| 33 | #include "cache.h" |
| 34 | #include "xattr.h" |
| 35 | #include "acl.h" |
| 36 | |
| 37 | static const struct inode_operations v9fs_dir_inode_operations; |
| 38 | static const struct inode_operations v9fs_dir_inode_operations_dotu; |
| 39 | static const struct inode_operations v9fs_file_inode_operations; |
| 40 | static const struct inode_operations v9fs_symlink_inode_operations; |
| 41 | |
| 42 | /** |
| 43 | * unixmode2p9mode - convert unix mode bits to plan 9 |
| 44 | * @v9ses: v9fs session information |
| 45 | * @mode: mode to convert |
| 46 | * |
| 47 | */ |
| 48 | |
| 49 | static u32 unixmode2p9mode(struct v9fs_session_info *v9ses, umode_t mode) |
| 50 | { |
| 51 | int res; |
| 52 | res = mode & 0777; |
| 53 | if (S_ISDIR(mode)) |
| 54 | res |= P9_DMDIR; |
| 55 | if (v9fs_proto_dotu(v9ses)) { |
| 56 | if (v9ses->nodev == 0) { |
| 57 | if (S_ISSOCK(mode)) |
| 58 | res |= P9_DMSOCKET; |
| 59 | if (S_ISFIFO(mode)) |
| 60 | res |= P9_DMNAMEDPIPE; |
| 61 | if (S_ISBLK(mode)) |
| 62 | res |= P9_DMDEVICE; |
| 63 | if (S_ISCHR(mode)) |
| 64 | res |= P9_DMDEVICE; |
| 65 | } |
| 66 | |
| 67 | if ((mode & S_ISUID) == S_ISUID) |
| 68 | res |= P9_DMSETUID; |
| 69 | if ((mode & S_ISGID) == S_ISGID) |
| 70 | res |= P9_DMSETGID; |
| 71 | if ((mode & S_ISVTX) == S_ISVTX) |
| 72 | res |= P9_DMSETVTX; |
| 73 | } |
| 74 | return res; |
| 75 | } |
| 76 | |
| 77 | /** |
| 78 | * p9mode2perm- convert plan9 mode bits to unix permission bits |
| 79 | * @v9ses: v9fs session information |
| 80 | * @stat: p9_wstat from which mode need to be derived |
| 81 | * |
| 82 | */ |
| 83 | static int p9mode2perm(struct v9fs_session_info *v9ses, |
| 84 | struct p9_wstat *stat) |
| 85 | { |
| 86 | int res; |
| 87 | int mode = stat->mode; |
| 88 | |
| 89 | res = mode & S_IALLUGO; |
| 90 | if (v9fs_proto_dotu(v9ses)) { |
| 91 | if ((mode & P9_DMSETUID) == P9_DMSETUID) |
| 92 | res |= S_ISUID; |
| 93 | |
| 94 | if ((mode & P9_DMSETGID) == P9_DMSETGID) |
| 95 | res |= S_ISGID; |
| 96 | |
| 97 | if ((mode & P9_DMSETVTX) == P9_DMSETVTX) |
| 98 | res |= S_ISVTX; |
| 99 | } |
| 100 | return res; |
| 101 | } |
| 102 | |
| 103 | /** |
| 104 | * p9mode2unixmode- convert plan9 mode bits to unix mode bits |
| 105 | * @v9ses: v9fs session information |
| 106 | * @stat: p9_wstat from which mode need to be derived |
| 107 | * @rdev: major number, minor number in case of device files. |
| 108 | * |
| 109 | */ |
| 110 | static umode_t p9mode2unixmode(struct v9fs_session_info *v9ses, |
| 111 | struct p9_wstat *stat, dev_t *rdev) |
| 112 | { |
| 113 | int res; |
| 114 | u32 mode = stat->mode; |
| 115 | |
| 116 | *rdev = 0; |
| 117 | res = p9mode2perm(v9ses, stat); |
| 118 | |
| 119 | if ((mode & P9_DMDIR) == P9_DMDIR) |
| 120 | res |= S_IFDIR; |
| 121 | else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses))) |
| 122 | res |= S_IFLNK; |
| 123 | else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses)) |
| 124 | && (v9ses->nodev == 0)) |
| 125 | res |= S_IFSOCK; |
| 126 | else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses)) |
| 127 | && (v9ses->nodev == 0)) |
| 128 | res |= S_IFIFO; |
| 129 | else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses)) |
| 130 | && (v9ses->nodev == 0)) { |
| 131 | char type = 0, ext[32]; |
| 132 | int major = -1, minor = -1; |
| 133 | |
| 134 | strlcpy(ext, stat->extension, sizeof(ext)); |
| 135 | sscanf(ext, "%c %i %i", &type, &major, &minor); |
| 136 | switch (type) { |
| 137 | case 'c': |
| 138 | res |= S_IFCHR; |
| 139 | break; |
| 140 | case 'b': |
| 141 | res |= S_IFBLK; |
| 142 | break; |
| 143 | default: |
| 144 | p9_debug(P9_DEBUG_ERROR, "Unknown special type %c %s\n", |
| 145 | type, stat->extension); |
| 146 | } |
| 147 | *rdev = MKDEV(major, minor); |
| 148 | } else |
| 149 | res |= S_IFREG; |
| 150 | |
| 151 | return res; |
| 152 | } |
| 153 | |
| 154 | /** |
| 155 | * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits |
| 156 | * @uflags: flags to convert |
| 157 | * @extended: if .u extensions are active |
| 158 | */ |
| 159 | |
| 160 | int v9fs_uflags2omode(int uflags, int extended) |
| 161 | { |
| 162 | int ret; |
| 163 | |
| 164 | ret = 0; |
| 165 | switch (uflags&3) { |
| 166 | default: |
| 167 | case O_RDONLY: |
| 168 | ret = P9_OREAD; |
| 169 | break; |
| 170 | |
| 171 | case O_WRONLY: |
| 172 | ret = P9_OWRITE; |
| 173 | break; |
| 174 | |
| 175 | case O_RDWR: |
| 176 | ret = P9_ORDWR; |
| 177 | break; |
| 178 | } |
| 179 | |
| 180 | if (extended) { |
| 181 | if (uflags & O_EXCL) |
| 182 | ret |= P9_OEXCL; |
| 183 | |
| 184 | if (uflags & O_APPEND) |
| 185 | ret |= P9_OAPPEND; |
| 186 | } |
| 187 | |
| 188 | return ret; |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * v9fs_blank_wstat - helper function to setup a 9P stat structure |
| 193 | * @wstat: structure to initialize |
| 194 | * |
| 195 | */ |
| 196 | |
| 197 | void |
| 198 | v9fs_blank_wstat(struct p9_wstat *wstat) |
| 199 | { |
| 200 | wstat->type = ~0; |
| 201 | wstat->dev = ~0; |
| 202 | wstat->qid.type = ~0; |
| 203 | wstat->qid.version = ~0; |
| 204 | *((long long *)&wstat->qid.path) = ~0; |
| 205 | wstat->mode = ~0; |
| 206 | wstat->atime = ~0; |
| 207 | wstat->mtime = ~0; |
| 208 | wstat->length = ~0; |
| 209 | wstat->name = NULL; |
| 210 | wstat->uid = NULL; |
| 211 | wstat->gid = NULL; |
| 212 | wstat->muid = NULL; |
| 213 | wstat->n_uid = INVALID_UID; |
| 214 | wstat->n_gid = INVALID_GID; |
| 215 | wstat->n_muid = INVALID_UID; |
| 216 | wstat->extension = NULL; |
| 217 | } |
| 218 | |
| 219 | /** |
| 220 | * v9fs_alloc_inode - helper function to allocate an inode |
| 221 | * |
| 222 | */ |
| 223 | struct inode *v9fs_alloc_inode(struct super_block *sb) |
| 224 | { |
| 225 | struct v9fs_inode *v9inode; |
| 226 | v9inode = (struct v9fs_inode *)kmem_cache_alloc(v9fs_inode_cache, |
| 227 | GFP_KERNEL); |
| 228 | if (!v9inode) |
| 229 | return NULL; |
| 230 | #ifdef CONFIG_9P_FSCACHE |
| 231 | v9inode->fscache = NULL; |
| 232 | mutex_init(&v9inode->fscache_lock); |
| 233 | #endif |
| 234 | v9inode->writeback_fid = NULL; |
| 235 | v9inode->cache_validity = 0; |
| 236 | mutex_init(&v9inode->v_mutex); |
| 237 | return &v9inode->vfs_inode; |
| 238 | } |
| 239 | |
| 240 | /** |
| 241 | * v9fs_free_inode - destroy an inode |
| 242 | * |
| 243 | */ |
| 244 | |
| 245 | void v9fs_free_inode(struct inode *inode) |
| 246 | { |
| 247 | kmem_cache_free(v9fs_inode_cache, V9FS_I(inode)); |
| 248 | } |
| 249 | |
| 250 | int v9fs_init_inode(struct v9fs_session_info *v9ses, |
| 251 | struct inode *inode, umode_t mode, dev_t rdev) |
| 252 | { |
| 253 | int err = 0; |
| 254 | |
| 255 | inode_init_owner(inode, NULL, mode); |
| 256 | inode->i_blocks = 0; |
| 257 | inode->i_rdev = rdev; |
| 258 | inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); |
| 259 | inode->i_mapping->a_ops = &v9fs_addr_operations; |
| 260 | |
| 261 | switch (mode & S_IFMT) { |
| 262 | case S_IFIFO: |
| 263 | case S_IFBLK: |
| 264 | case S_IFCHR: |
| 265 | case S_IFSOCK: |
| 266 | if (v9fs_proto_dotl(v9ses)) { |
| 267 | inode->i_op = &v9fs_file_inode_operations_dotl; |
| 268 | } else if (v9fs_proto_dotu(v9ses)) { |
| 269 | inode->i_op = &v9fs_file_inode_operations; |
| 270 | } else { |
| 271 | p9_debug(P9_DEBUG_ERROR, |
| 272 | "special files without extended mode\n"); |
| 273 | err = -EINVAL; |
| 274 | goto error; |
| 275 | } |
| 276 | init_special_inode(inode, inode->i_mode, inode->i_rdev); |
| 277 | break; |
| 278 | case S_IFREG: |
| 279 | if (v9fs_proto_dotl(v9ses)) { |
| 280 | inode->i_op = &v9fs_file_inode_operations_dotl; |
| 281 | if (v9ses->cache == CACHE_LOOSE || |
| 282 | v9ses->cache == CACHE_FSCACHE) |
| 283 | inode->i_fop = |
| 284 | &v9fs_cached_file_operations_dotl; |
| 285 | else if (v9ses->cache == CACHE_MMAP) |
| 286 | inode->i_fop = &v9fs_mmap_file_operations_dotl; |
| 287 | else |
| 288 | inode->i_fop = &v9fs_file_operations_dotl; |
| 289 | } else { |
| 290 | inode->i_op = &v9fs_file_inode_operations; |
| 291 | if (v9ses->cache == CACHE_LOOSE || |
| 292 | v9ses->cache == CACHE_FSCACHE) |
| 293 | inode->i_fop = |
| 294 | &v9fs_cached_file_operations; |
| 295 | else if (v9ses->cache == CACHE_MMAP) |
| 296 | inode->i_fop = &v9fs_mmap_file_operations; |
| 297 | else |
| 298 | inode->i_fop = &v9fs_file_operations; |
| 299 | } |
| 300 | |
| 301 | break; |
| 302 | case S_IFLNK: |
| 303 | if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) { |
| 304 | p9_debug(P9_DEBUG_ERROR, |
| 305 | "extended modes used with legacy protocol\n"); |
| 306 | err = -EINVAL; |
| 307 | goto error; |
| 308 | } |
| 309 | |
| 310 | if (v9fs_proto_dotl(v9ses)) |
| 311 | inode->i_op = &v9fs_symlink_inode_operations_dotl; |
| 312 | else |
| 313 | inode->i_op = &v9fs_symlink_inode_operations; |
| 314 | |
| 315 | break; |
| 316 | case S_IFDIR: |
| 317 | inc_nlink(inode); |
| 318 | if (v9fs_proto_dotl(v9ses)) |
| 319 | inode->i_op = &v9fs_dir_inode_operations_dotl; |
| 320 | else if (v9fs_proto_dotu(v9ses)) |
| 321 | inode->i_op = &v9fs_dir_inode_operations_dotu; |
| 322 | else |
| 323 | inode->i_op = &v9fs_dir_inode_operations; |
| 324 | |
| 325 | if (v9fs_proto_dotl(v9ses)) |
| 326 | inode->i_fop = &v9fs_dir_operations_dotl; |
| 327 | else |
| 328 | inode->i_fop = &v9fs_dir_operations; |
| 329 | |
| 330 | break; |
| 331 | default: |
| 332 | p9_debug(P9_DEBUG_ERROR, "BAD mode 0x%hx S_IFMT 0x%x\n", |
| 333 | mode, mode & S_IFMT); |
| 334 | err = -EINVAL; |
| 335 | goto error; |
| 336 | } |
| 337 | error: |
| 338 | return err; |
| 339 | |
| 340 | } |
| 341 | |
| 342 | /** |
| 343 | * v9fs_get_inode - helper function to setup an inode |
| 344 | * @sb: superblock |
| 345 | * @mode: mode to setup inode with |
| 346 | * |
| 347 | */ |
| 348 | |
| 349 | struct inode *v9fs_get_inode(struct super_block *sb, umode_t mode, dev_t rdev) |
| 350 | { |
| 351 | int err; |
| 352 | struct inode *inode; |
| 353 | struct v9fs_session_info *v9ses = sb->s_fs_info; |
| 354 | |
| 355 | p9_debug(P9_DEBUG_VFS, "super block: %p mode: %ho\n", sb, mode); |
| 356 | |
| 357 | inode = new_inode(sb); |
| 358 | if (!inode) { |
| 359 | pr_warn("%s (%d): Problem allocating inode\n", |
| 360 | __func__, task_pid_nr(current)); |
| 361 | return ERR_PTR(-ENOMEM); |
| 362 | } |
| 363 | err = v9fs_init_inode(v9ses, inode, mode, rdev); |
| 364 | if (err) { |
| 365 | iput(inode); |
| 366 | return ERR_PTR(err); |
| 367 | } |
| 368 | return inode; |
| 369 | } |
| 370 | |
| 371 | /* |
| 372 | static struct v9fs_fid* |
| 373 | v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry) |
| 374 | { |
| 375 | int err; |
| 376 | int nfid; |
| 377 | struct v9fs_fid *ret; |
| 378 | struct v9fs_fcall *fcall; |
| 379 | |
| 380 | nfid = v9fs_get_idpool(&v9ses->fidpool); |
| 381 | if (nfid < 0) { |
| 382 | eprintk(KERN_WARNING, "no free fids available\n"); |
| 383 | return ERR_PTR(-ENOSPC); |
| 384 | } |
| 385 | |
| 386 | err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name, |
| 387 | &fcall); |
| 388 | |
| 389 | if (err < 0) { |
| 390 | if (fcall && fcall->id == RWALK) |
| 391 | goto clunk_fid; |
| 392 | |
| 393 | PRINT_FCALL_ERROR("walk error", fcall); |
| 394 | v9fs_put_idpool(nfid, &v9ses->fidpool); |
| 395 | goto error; |
| 396 | } |
| 397 | |
| 398 | kfree(fcall); |
| 399 | fcall = NULL; |
| 400 | ret = v9fs_fid_create(v9ses, nfid); |
| 401 | if (!ret) { |
| 402 | err = -ENOMEM; |
| 403 | goto clunk_fid; |
| 404 | } |
| 405 | |
| 406 | err = v9fs_fid_insert(ret, dentry); |
| 407 | if (err < 0) { |
| 408 | v9fs_fid_destroy(ret); |
| 409 | goto clunk_fid; |
| 410 | } |
| 411 | |
| 412 | return ret; |
| 413 | |
| 414 | clunk_fid: |
| 415 | v9fs_t_clunk(v9ses, nfid); |
| 416 | |
| 417 | error: |
| 418 | kfree(fcall); |
| 419 | return ERR_PTR(err); |
| 420 | } |
| 421 | */ |
| 422 | |
| 423 | |
| 424 | /** |
| 425 | * v9fs_clear_inode - release an inode |
| 426 | * @inode: inode to release |
| 427 | * |
| 428 | */ |
| 429 | void v9fs_evict_inode(struct inode *inode) |
| 430 | { |
| 431 | struct v9fs_inode *v9inode = V9FS_I(inode); |
| 432 | |
| 433 | truncate_inode_pages_final(&inode->i_data); |
| 434 | clear_inode(inode); |
| 435 | filemap_fdatawrite(&inode->i_data); |
| 436 | |
| 437 | v9fs_cache_inode_put_cookie(inode); |
| 438 | /* clunk the fid stashed in writeback_fid */ |
| 439 | if (v9inode->writeback_fid) { |
| 440 | p9_client_clunk(v9inode->writeback_fid); |
| 441 | v9inode->writeback_fid = NULL; |
| 442 | } |
| 443 | } |
| 444 | |
| 445 | static int v9fs_test_inode(struct inode *inode, void *data) |
| 446 | { |
| 447 | int umode; |
| 448 | dev_t rdev; |
| 449 | struct v9fs_inode *v9inode = V9FS_I(inode); |
| 450 | struct p9_wstat *st = (struct p9_wstat *)data; |
| 451 | struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode); |
| 452 | |
| 453 | umode = p9mode2unixmode(v9ses, st, &rdev); |
| 454 | /* don't match inode of different type */ |
| 455 | if ((inode->i_mode & S_IFMT) != (umode & S_IFMT)) |
| 456 | return 0; |
| 457 | |
| 458 | /* compare qid details */ |
| 459 | if (memcmp(&v9inode->qid.version, |
| 460 | &st->qid.version, sizeof(v9inode->qid.version))) |
| 461 | return 0; |
| 462 | |
| 463 | if (v9inode->qid.type != st->qid.type) |
| 464 | return 0; |
| 465 | |
| 466 | if (v9inode->qid.path != st->qid.path) |
| 467 | return 0; |
| 468 | return 1; |
| 469 | } |
| 470 | |
| 471 | static int v9fs_test_new_inode(struct inode *inode, void *data) |
| 472 | { |
| 473 | return 0; |
| 474 | } |
| 475 | |
| 476 | static int v9fs_set_inode(struct inode *inode, void *data) |
| 477 | { |
| 478 | struct v9fs_inode *v9inode = V9FS_I(inode); |
| 479 | struct p9_wstat *st = (struct p9_wstat *)data; |
| 480 | |
| 481 | memcpy(&v9inode->qid, &st->qid, sizeof(st->qid)); |
| 482 | return 0; |
| 483 | } |
| 484 | |
| 485 | static struct inode *v9fs_qid_iget(struct super_block *sb, |
| 486 | struct p9_qid *qid, |
| 487 | struct p9_wstat *st, |
| 488 | int new) |
| 489 | { |
| 490 | dev_t rdev; |
| 491 | int retval; |
| 492 | umode_t umode; |
| 493 | unsigned long i_ino; |
| 494 | struct inode *inode; |
| 495 | struct v9fs_session_info *v9ses = sb->s_fs_info; |
| 496 | int (*test)(struct inode *, void *); |
| 497 | |
| 498 | if (new) |
| 499 | test = v9fs_test_new_inode; |
| 500 | else |
| 501 | test = v9fs_test_inode; |
| 502 | |
| 503 | i_ino = v9fs_qid2ino(qid); |
| 504 | inode = iget5_locked(sb, i_ino, test, v9fs_set_inode, st); |
| 505 | if (!inode) |
| 506 | return ERR_PTR(-ENOMEM); |
| 507 | if (!(inode->i_state & I_NEW)) |
| 508 | return inode; |
| 509 | /* |
| 510 | * initialize the inode with the stat info |
| 511 | * FIXME!! we may need support for stale inodes |
| 512 | * later. |
| 513 | */ |
| 514 | inode->i_ino = i_ino; |
| 515 | umode = p9mode2unixmode(v9ses, st, &rdev); |
| 516 | retval = v9fs_init_inode(v9ses, inode, umode, rdev); |
| 517 | if (retval) |
| 518 | goto error; |
| 519 | |
| 520 | v9fs_stat2inode(st, inode, sb, 0); |
| 521 | v9fs_cache_inode_get_cookie(inode); |
| 522 | unlock_new_inode(inode); |
| 523 | return inode; |
| 524 | error: |
| 525 | iget_failed(inode); |
| 526 | return ERR_PTR(retval); |
| 527 | |
| 528 | } |
| 529 | |
| 530 | struct inode * |
| 531 | v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid, |
| 532 | struct super_block *sb, int new) |
| 533 | { |
| 534 | struct p9_wstat *st; |
| 535 | struct inode *inode = NULL; |
| 536 | |
| 537 | st = p9_client_stat(fid); |
| 538 | if (IS_ERR(st)) |
| 539 | return ERR_CAST(st); |
| 540 | |
| 541 | inode = v9fs_qid_iget(sb, &st->qid, st, new); |
| 542 | p9stat_free(st); |
| 543 | kfree(st); |
| 544 | return inode; |
| 545 | } |
| 546 | |
| 547 | /** |
| 548 | * v9fs_at_to_dotl_flags- convert Linux specific AT flags to |
| 549 | * plan 9 AT flag. |
| 550 | * @flags: flags to convert |
| 551 | */ |
| 552 | static int v9fs_at_to_dotl_flags(int flags) |
| 553 | { |
| 554 | int rflags = 0; |
| 555 | if (flags & AT_REMOVEDIR) |
| 556 | rflags |= P9_DOTL_AT_REMOVEDIR; |
| 557 | return rflags; |
| 558 | } |
| 559 | |
| 560 | /** |
| 561 | * v9fs_dec_count - helper functon to drop i_nlink. |
| 562 | * |
| 563 | * If a directory had nlink <= 2 (including . and ..), then we should not drop |
| 564 | * the link count, which indicates the underlying exported fs doesn't maintain |
| 565 | * nlink accurately. e.g. |
| 566 | * - overlayfs sets nlink to 1 for merged dir |
| 567 | * - ext4 (with dir_nlink feature enabled) sets nlink to 1 if a dir has more |
| 568 | * than EXT4_LINK_MAX (65000) links. |
| 569 | * |
| 570 | * @inode: inode whose nlink is being dropped |
| 571 | */ |
| 572 | static void v9fs_dec_count(struct inode *inode) |
| 573 | { |
| 574 | if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) |
| 575 | drop_nlink(inode); |
| 576 | } |
| 577 | |
| 578 | /** |
| 579 | * v9fs_remove - helper function to remove files and directories |
| 580 | * @dir: directory inode that is being deleted |
| 581 | * @dentry: dentry that is being deleted |
| 582 | * @flags: removing a directory |
| 583 | * |
| 584 | */ |
| 585 | |
| 586 | static int v9fs_remove(struct inode *dir, struct dentry *dentry, int flags) |
| 587 | { |
| 588 | struct inode *inode; |
| 589 | int retval = -EOPNOTSUPP; |
| 590 | struct p9_fid *v9fid, *dfid; |
| 591 | struct v9fs_session_info *v9ses; |
| 592 | |
| 593 | p9_debug(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %x\n", |
| 594 | dir, dentry, flags); |
| 595 | |
| 596 | v9ses = v9fs_inode2v9ses(dir); |
| 597 | inode = d_inode(dentry); |
| 598 | dfid = v9fs_parent_fid(dentry); |
| 599 | if (IS_ERR(dfid)) { |
| 600 | retval = PTR_ERR(dfid); |
| 601 | p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", retval); |
| 602 | return retval; |
| 603 | } |
| 604 | if (v9fs_proto_dotl(v9ses)) |
| 605 | retval = p9_client_unlinkat(dfid, dentry->d_name.name, |
| 606 | v9fs_at_to_dotl_flags(flags)); |
| 607 | if (retval == -EOPNOTSUPP) { |
| 608 | /* Try the one based on path */ |
| 609 | v9fid = v9fs_fid_clone(dentry); |
| 610 | if (IS_ERR(v9fid)) |
| 611 | return PTR_ERR(v9fid); |
| 612 | retval = p9_client_remove(v9fid); |
| 613 | } |
| 614 | if (!retval) { |
| 615 | /* |
| 616 | * directories on unlink should have zero |
| 617 | * link count |
| 618 | */ |
| 619 | if (flags & AT_REMOVEDIR) { |
| 620 | clear_nlink(inode); |
| 621 | v9fs_dec_count(dir); |
| 622 | } else |
| 623 | v9fs_dec_count(inode); |
| 624 | |
| 625 | v9fs_invalidate_inode_attr(inode); |
| 626 | v9fs_invalidate_inode_attr(dir); |
| 627 | } |
| 628 | return retval; |
| 629 | } |
| 630 | |
| 631 | /** |
| 632 | * v9fs_create - Create a file |
| 633 | * @v9ses: session information |
| 634 | * @dir: directory that dentry is being created in |
| 635 | * @dentry: dentry that is being created |
| 636 | * @extension: 9p2000.u extension string to support devices, etc. |
| 637 | * @perm: create permissions |
| 638 | * @mode: open mode |
| 639 | * |
| 640 | */ |
| 641 | static struct p9_fid * |
| 642 | v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir, |
| 643 | struct dentry *dentry, char *extension, u32 perm, u8 mode) |
| 644 | { |
| 645 | int err; |
| 646 | const unsigned char *name; |
| 647 | struct p9_fid *dfid, *ofid, *fid; |
| 648 | struct inode *inode; |
| 649 | |
| 650 | p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry); |
| 651 | |
| 652 | err = 0; |
| 653 | ofid = NULL; |
| 654 | fid = NULL; |
| 655 | name = dentry->d_name.name; |
| 656 | dfid = v9fs_parent_fid(dentry); |
| 657 | if (IS_ERR(dfid)) { |
| 658 | err = PTR_ERR(dfid); |
| 659 | p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err); |
| 660 | return ERR_PTR(err); |
| 661 | } |
| 662 | |
| 663 | /* clone a fid to use for creation */ |
| 664 | ofid = clone_fid(dfid); |
| 665 | if (IS_ERR(ofid)) { |
| 666 | err = PTR_ERR(ofid); |
| 667 | p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err); |
| 668 | return ERR_PTR(err); |
| 669 | } |
| 670 | |
| 671 | err = p9_client_fcreate(ofid, name, perm, mode, extension); |
| 672 | if (err < 0) { |
| 673 | p9_debug(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err); |
| 674 | goto error; |
| 675 | } |
| 676 | |
| 677 | if (!(perm & P9_DMLINK)) { |
| 678 | /* now walk from the parent so we can get unopened fid */ |
| 679 | fid = p9_client_walk(dfid, 1, &name, 1); |
| 680 | if (IS_ERR(fid)) { |
| 681 | err = PTR_ERR(fid); |
| 682 | p9_debug(P9_DEBUG_VFS, |
| 683 | "p9_client_walk failed %d\n", err); |
| 684 | fid = NULL; |
| 685 | goto error; |
| 686 | } |
| 687 | /* |
| 688 | * instantiate inode and assign the unopened fid to the dentry |
| 689 | */ |
| 690 | inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb); |
| 691 | if (IS_ERR(inode)) { |
| 692 | err = PTR_ERR(inode); |
| 693 | p9_debug(P9_DEBUG_VFS, |
| 694 | "inode creation failed %d\n", err); |
| 695 | goto error; |
| 696 | } |
| 697 | v9fs_fid_add(dentry, fid); |
| 698 | d_instantiate(dentry, inode); |
| 699 | } |
| 700 | return ofid; |
| 701 | error: |
| 702 | if (ofid) |
| 703 | p9_client_clunk(ofid); |
| 704 | |
| 705 | if (fid) |
| 706 | p9_client_clunk(fid); |
| 707 | |
| 708 | return ERR_PTR(err); |
| 709 | } |
| 710 | |
| 711 | /** |
| 712 | * v9fs_vfs_create - VFS hook to create a regular file |
| 713 | * |
| 714 | * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open(). This is only called |
| 715 | * for mknod(2). |
| 716 | * |
| 717 | * @dir: directory inode that is being created |
| 718 | * @dentry: dentry that is being deleted |
| 719 | * @mode: create permissions |
| 720 | * |
| 721 | */ |
| 722 | |
| 723 | static int |
| 724 | v9fs_vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, |
| 725 | bool excl) |
| 726 | { |
| 727 | struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir); |
| 728 | u32 perm = unixmode2p9mode(v9ses, mode); |
| 729 | struct p9_fid *fid; |
| 730 | |
| 731 | /* P9_OEXCL? */ |
| 732 | fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_ORDWR); |
| 733 | if (IS_ERR(fid)) |
| 734 | return PTR_ERR(fid); |
| 735 | |
| 736 | v9fs_invalidate_inode_attr(dir); |
| 737 | p9_client_clunk(fid); |
| 738 | |
| 739 | return 0; |
| 740 | } |
| 741 | |
| 742 | /** |
| 743 | * v9fs_vfs_mkdir - VFS mkdir hook to create a directory |
| 744 | * @dir: inode that is being unlinked |
| 745 | * @dentry: dentry that is being unlinked |
| 746 | * @mode: mode for new directory |
| 747 | * |
| 748 | */ |
| 749 | |
| 750 | static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) |
| 751 | { |
| 752 | int err; |
| 753 | u32 perm; |
| 754 | struct p9_fid *fid; |
| 755 | struct v9fs_session_info *v9ses; |
| 756 | |
| 757 | p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry); |
| 758 | err = 0; |
| 759 | v9ses = v9fs_inode2v9ses(dir); |
| 760 | perm = unixmode2p9mode(v9ses, mode | S_IFDIR); |
| 761 | fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD); |
| 762 | if (IS_ERR(fid)) { |
| 763 | err = PTR_ERR(fid); |
| 764 | fid = NULL; |
| 765 | } else { |
| 766 | inc_nlink(dir); |
| 767 | v9fs_invalidate_inode_attr(dir); |
| 768 | } |
| 769 | |
| 770 | if (fid) |
| 771 | p9_client_clunk(fid); |
| 772 | |
| 773 | return err; |
| 774 | } |
| 775 | |
| 776 | /** |
| 777 | * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode |
| 778 | * @dir: inode that is being walked from |
| 779 | * @dentry: dentry that is being walked to? |
| 780 | * @flags: lookup flags (unused) |
| 781 | * |
| 782 | */ |
| 783 | |
| 784 | struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, |
| 785 | unsigned int flags) |
| 786 | { |
| 787 | struct dentry *res; |
| 788 | struct v9fs_session_info *v9ses; |
| 789 | struct p9_fid *dfid, *fid; |
| 790 | struct inode *inode; |
| 791 | const unsigned char *name; |
| 792 | |
| 793 | p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%pd) %p flags: %x\n", |
| 794 | dir, dentry, dentry, flags); |
| 795 | |
| 796 | if (dentry->d_name.len > NAME_MAX) |
| 797 | return ERR_PTR(-ENAMETOOLONG); |
| 798 | |
| 799 | v9ses = v9fs_inode2v9ses(dir); |
| 800 | /* We can walk d_parent because we hold the dir->i_mutex */ |
| 801 | dfid = v9fs_parent_fid(dentry); |
| 802 | if (IS_ERR(dfid)) |
| 803 | return ERR_CAST(dfid); |
| 804 | |
| 805 | /* |
| 806 | * Make sure we don't use a wrong inode due to parallel |
| 807 | * unlink. For cached mode create calls request for new |
| 808 | * inode. But with cache disabled, lookup should do this. |
| 809 | */ |
| 810 | name = dentry->d_name.name; |
| 811 | fid = p9_client_walk(dfid, 1, &name, 1); |
| 812 | if (fid == ERR_PTR(-ENOENT)) |
| 813 | inode = NULL; |
| 814 | else if (IS_ERR(fid)) |
| 815 | inode = ERR_CAST(fid); |
| 816 | else if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) |
| 817 | inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb); |
| 818 | else |
| 819 | inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb); |
| 820 | /* |
| 821 | * If we had a rename on the server and a parallel lookup |
| 822 | * for the new name, then make sure we instantiate with |
| 823 | * the new name. ie look up for a/b, while on server somebody |
| 824 | * moved b under k and client parallely did a lookup for |
| 825 | * k/b. |
| 826 | */ |
| 827 | res = d_splice_alias(inode, dentry); |
| 828 | if (!IS_ERR(fid)) { |
| 829 | if (!res) |
| 830 | v9fs_fid_add(dentry, fid); |
| 831 | else if (!IS_ERR(res)) |
| 832 | v9fs_fid_add(res, fid); |
| 833 | else |
| 834 | p9_client_clunk(fid); |
| 835 | } |
| 836 | return res; |
| 837 | } |
| 838 | |
| 839 | static int |
| 840 | v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry, |
| 841 | struct file *file, unsigned flags, umode_t mode) |
| 842 | { |
| 843 | int err; |
| 844 | u32 perm; |
| 845 | struct v9fs_inode *v9inode; |
| 846 | struct v9fs_session_info *v9ses; |
| 847 | struct p9_fid *fid, *inode_fid; |
| 848 | struct dentry *res = NULL; |
| 849 | |
| 850 | if (d_in_lookup(dentry)) { |
| 851 | res = v9fs_vfs_lookup(dir, dentry, 0); |
| 852 | if (IS_ERR(res)) |
| 853 | return PTR_ERR(res); |
| 854 | |
| 855 | if (res) |
| 856 | dentry = res; |
| 857 | } |
| 858 | |
| 859 | /* Only creates */ |
| 860 | if (!(flags & O_CREAT) || d_really_is_positive(dentry)) |
| 861 | return finish_no_open(file, res); |
| 862 | |
| 863 | err = 0; |
| 864 | |
| 865 | v9ses = v9fs_inode2v9ses(dir); |
| 866 | perm = unixmode2p9mode(v9ses, mode); |
| 867 | fid = v9fs_create(v9ses, dir, dentry, NULL, perm, |
| 868 | v9fs_uflags2omode(flags, |
| 869 | v9fs_proto_dotu(v9ses))); |
| 870 | if (IS_ERR(fid)) { |
| 871 | err = PTR_ERR(fid); |
| 872 | fid = NULL; |
| 873 | goto error; |
| 874 | } |
| 875 | |
| 876 | v9fs_invalidate_inode_attr(dir); |
| 877 | v9inode = V9FS_I(d_inode(dentry)); |
| 878 | mutex_lock(&v9inode->v_mutex); |
| 879 | if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) && |
| 880 | !v9inode->writeback_fid && |
| 881 | ((flags & O_ACCMODE) != O_RDONLY)) { |
| 882 | /* |
| 883 | * clone a fid and add it to writeback_fid |
| 884 | * we do it during open time instead of |
| 885 | * page dirty time via write_begin/page_mkwrite |
| 886 | * because we want write after unlink usecase |
| 887 | * to work. |
| 888 | */ |
| 889 | inode_fid = v9fs_writeback_fid(dentry); |
| 890 | if (IS_ERR(inode_fid)) { |
| 891 | err = PTR_ERR(inode_fid); |
| 892 | mutex_unlock(&v9inode->v_mutex); |
| 893 | goto error; |
| 894 | } |
| 895 | v9inode->writeback_fid = (void *) inode_fid; |
| 896 | } |
| 897 | mutex_unlock(&v9inode->v_mutex); |
| 898 | err = finish_open(file, dentry, generic_file_open); |
| 899 | if (err) |
| 900 | goto error; |
| 901 | |
| 902 | file->private_data = fid; |
| 903 | if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) |
| 904 | v9fs_cache_inode_set_cookie(d_inode(dentry), file); |
| 905 | |
| 906 | file->f_mode |= FMODE_CREATED; |
| 907 | out: |
| 908 | dput(res); |
| 909 | return err; |
| 910 | |
| 911 | error: |
| 912 | if (fid) |
| 913 | p9_client_clunk(fid); |
| 914 | goto out; |
| 915 | } |
| 916 | |
| 917 | /** |
| 918 | * v9fs_vfs_unlink - VFS unlink hook to delete an inode |
| 919 | * @i: inode that is being unlinked |
| 920 | * @d: dentry that is being unlinked |
| 921 | * |
| 922 | */ |
| 923 | |
| 924 | int v9fs_vfs_unlink(struct inode *i, struct dentry *d) |
| 925 | { |
| 926 | return v9fs_remove(i, d, 0); |
| 927 | } |
| 928 | |
| 929 | /** |
| 930 | * v9fs_vfs_rmdir - VFS unlink hook to delete a directory |
| 931 | * @i: inode that is being unlinked |
| 932 | * @d: dentry that is being unlinked |
| 933 | * |
| 934 | */ |
| 935 | |
| 936 | int v9fs_vfs_rmdir(struct inode *i, struct dentry *d) |
| 937 | { |
| 938 | return v9fs_remove(i, d, AT_REMOVEDIR); |
| 939 | } |
| 940 | |
| 941 | /** |
| 942 | * v9fs_vfs_rename - VFS hook to rename an inode |
| 943 | * @old_dir: old dir inode |
| 944 | * @old_dentry: old dentry |
| 945 | * @new_dir: new dir inode |
| 946 | * @new_dentry: new dentry |
| 947 | * |
| 948 | */ |
| 949 | |
| 950 | int |
| 951 | v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry, |
| 952 | struct inode *new_dir, struct dentry *new_dentry, |
| 953 | unsigned int flags) |
| 954 | { |
| 955 | int retval; |
| 956 | struct inode *old_inode; |
| 957 | struct inode *new_inode; |
| 958 | struct v9fs_session_info *v9ses; |
| 959 | struct p9_fid *oldfid; |
| 960 | struct p9_fid *olddirfid; |
| 961 | struct p9_fid *newdirfid; |
| 962 | struct p9_wstat wstat; |
| 963 | |
| 964 | if (flags) |
| 965 | return -EINVAL; |
| 966 | |
| 967 | p9_debug(P9_DEBUG_VFS, "\n"); |
| 968 | retval = 0; |
| 969 | old_inode = d_inode(old_dentry); |
| 970 | new_inode = d_inode(new_dentry); |
| 971 | v9ses = v9fs_inode2v9ses(old_inode); |
| 972 | oldfid = v9fs_fid_lookup(old_dentry); |
| 973 | if (IS_ERR(oldfid)) |
| 974 | return PTR_ERR(oldfid); |
| 975 | |
| 976 | olddirfid = clone_fid(v9fs_parent_fid(old_dentry)); |
| 977 | if (IS_ERR(olddirfid)) { |
| 978 | retval = PTR_ERR(olddirfid); |
| 979 | goto done; |
| 980 | } |
| 981 | |
| 982 | newdirfid = clone_fid(v9fs_parent_fid(new_dentry)); |
| 983 | if (IS_ERR(newdirfid)) { |
| 984 | retval = PTR_ERR(newdirfid); |
| 985 | goto clunk_olddir; |
| 986 | } |
| 987 | |
| 988 | down_write(&v9ses->rename_sem); |
| 989 | if (v9fs_proto_dotl(v9ses)) { |
| 990 | retval = p9_client_renameat(olddirfid, old_dentry->d_name.name, |
| 991 | newdirfid, new_dentry->d_name.name); |
| 992 | if (retval == -EOPNOTSUPP) |
| 993 | retval = p9_client_rename(oldfid, newdirfid, |
| 994 | new_dentry->d_name.name); |
| 995 | if (retval != -EOPNOTSUPP) |
| 996 | goto clunk_newdir; |
| 997 | } |
| 998 | if (old_dentry->d_parent != new_dentry->d_parent) { |
| 999 | /* |
| 1000 | * 9P .u can only handle file rename in the same directory |
| 1001 | */ |
| 1002 | |
| 1003 | p9_debug(P9_DEBUG_ERROR, "old dir and new dir are different\n"); |
| 1004 | retval = -EXDEV; |
| 1005 | goto clunk_newdir; |
| 1006 | } |
| 1007 | v9fs_blank_wstat(&wstat); |
| 1008 | wstat.muid = v9ses->uname; |
| 1009 | wstat.name = new_dentry->d_name.name; |
| 1010 | retval = p9_client_wstat(oldfid, &wstat); |
| 1011 | |
| 1012 | clunk_newdir: |
| 1013 | if (!retval) { |
| 1014 | if (new_inode) { |
| 1015 | if (S_ISDIR(new_inode->i_mode)) |
| 1016 | clear_nlink(new_inode); |
| 1017 | else |
| 1018 | v9fs_dec_count(new_inode); |
| 1019 | } |
| 1020 | if (S_ISDIR(old_inode->i_mode)) { |
| 1021 | if (!new_inode) |
| 1022 | inc_nlink(new_dir); |
| 1023 | v9fs_dec_count(old_dir); |
| 1024 | } |
| 1025 | v9fs_invalidate_inode_attr(old_inode); |
| 1026 | v9fs_invalidate_inode_attr(old_dir); |
| 1027 | v9fs_invalidate_inode_attr(new_dir); |
| 1028 | |
| 1029 | /* successful rename */ |
| 1030 | d_move(old_dentry, new_dentry); |
| 1031 | } |
| 1032 | up_write(&v9ses->rename_sem); |
| 1033 | p9_client_clunk(newdirfid); |
| 1034 | |
| 1035 | clunk_olddir: |
| 1036 | p9_client_clunk(olddirfid); |
| 1037 | |
| 1038 | done: |
| 1039 | return retval; |
| 1040 | } |
| 1041 | |
| 1042 | /** |
| 1043 | * v9fs_vfs_getattr - retrieve file metadata |
| 1044 | * @path: Object to query |
| 1045 | * @stat: metadata structure to populate |
| 1046 | * @request_mask: Mask of STATX_xxx flags indicating the caller's interests |
| 1047 | * @flags: AT_STATX_xxx setting |
| 1048 | * |
| 1049 | */ |
| 1050 | |
| 1051 | static int |
| 1052 | v9fs_vfs_getattr(const struct path *path, struct kstat *stat, |
| 1053 | u32 request_mask, unsigned int flags) |
| 1054 | { |
| 1055 | struct dentry *dentry = path->dentry; |
| 1056 | struct v9fs_session_info *v9ses; |
| 1057 | struct p9_fid *fid; |
| 1058 | struct p9_wstat *st; |
| 1059 | |
| 1060 | p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry); |
| 1061 | v9ses = v9fs_dentry2v9ses(dentry); |
| 1062 | if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) { |
| 1063 | generic_fillattr(d_inode(dentry), stat); |
| 1064 | return 0; |
| 1065 | } |
| 1066 | fid = v9fs_fid_lookup(dentry); |
| 1067 | if (IS_ERR(fid)) |
| 1068 | return PTR_ERR(fid); |
| 1069 | |
| 1070 | st = p9_client_stat(fid); |
| 1071 | if (IS_ERR(st)) |
| 1072 | return PTR_ERR(st); |
| 1073 | |
| 1074 | v9fs_stat2inode(st, d_inode(dentry), dentry->d_sb, 0); |
| 1075 | generic_fillattr(d_inode(dentry), stat); |
| 1076 | |
| 1077 | p9stat_free(st); |
| 1078 | kfree(st); |
| 1079 | return 0; |
| 1080 | } |
| 1081 | |
| 1082 | /** |
| 1083 | * v9fs_vfs_setattr - set file metadata |
| 1084 | * @dentry: file whose metadata to set |
| 1085 | * @iattr: metadata assignment structure |
| 1086 | * |
| 1087 | */ |
| 1088 | |
| 1089 | static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr) |
| 1090 | { |
| 1091 | int retval; |
| 1092 | struct v9fs_session_info *v9ses; |
| 1093 | struct p9_fid *fid; |
| 1094 | struct p9_wstat wstat; |
| 1095 | |
| 1096 | p9_debug(P9_DEBUG_VFS, "\n"); |
| 1097 | retval = setattr_prepare(dentry, iattr); |
| 1098 | if (retval) |
| 1099 | return retval; |
| 1100 | |
| 1101 | retval = -EPERM; |
| 1102 | v9ses = v9fs_dentry2v9ses(dentry); |
| 1103 | fid = v9fs_fid_lookup(dentry); |
| 1104 | if(IS_ERR(fid)) |
| 1105 | return PTR_ERR(fid); |
| 1106 | |
| 1107 | v9fs_blank_wstat(&wstat); |
| 1108 | if (iattr->ia_valid & ATTR_MODE) |
| 1109 | wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode); |
| 1110 | |
| 1111 | if (iattr->ia_valid & ATTR_MTIME) |
| 1112 | wstat.mtime = iattr->ia_mtime.tv_sec; |
| 1113 | |
| 1114 | if (iattr->ia_valid & ATTR_ATIME) |
| 1115 | wstat.atime = iattr->ia_atime.tv_sec; |
| 1116 | |
| 1117 | if (iattr->ia_valid & ATTR_SIZE) |
| 1118 | wstat.length = iattr->ia_size; |
| 1119 | |
| 1120 | if (v9fs_proto_dotu(v9ses)) { |
| 1121 | if (iattr->ia_valid & ATTR_UID) |
| 1122 | wstat.n_uid = iattr->ia_uid; |
| 1123 | |
| 1124 | if (iattr->ia_valid & ATTR_GID) |
| 1125 | wstat.n_gid = iattr->ia_gid; |
| 1126 | } |
| 1127 | |
| 1128 | /* Write all dirty data */ |
| 1129 | if (d_is_reg(dentry)) |
| 1130 | filemap_write_and_wait(d_inode(dentry)->i_mapping); |
| 1131 | |
| 1132 | retval = p9_client_wstat(fid, &wstat); |
| 1133 | if (retval < 0) |
| 1134 | return retval; |
| 1135 | |
| 1136 | if ((iattr->ia_valid & ATTR_SIZE) && |
| 1137 | iattr->ia_size != i_size_read(d_inode(dentry))) |
| 1138 | truncate_setsize(d_inode(dentry), iattr->ia_size); |
| 1139 | |
| 1140 | v9fs_invalidate_inode_attr(d_inode(dentry)); |
| 1141 | |
| 1142 | setattr_copy(d_inode(dentry), iattr); |
| 1143 | mark_inode_dirty(d_inode(dentry)); |
| 1144 | return 0; |
| 1145 | } |
| 1146 | |
| 1147 | /** |
| 1148 | * v9fs_stat2inode - populate an inode structure with mistat info |
| 1149 | * @stat: Plan 9 metadata (mistat) structure |
| 1150 | * @inode: inode to populate |
| 1151 | * @sb: superblock of filesystem |
| 1152 | * @flags: control flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE) |
| 1153 | * |
| 1154 | */ |
| 1155 | |
| 1156 | void |
| 1157 | v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode, |
| 1158 | struct super_block *sb, unsigned int flags) |
| 1159 | { |
| 1160 | umode_t mode; |
| 1161 | char ext[32]; |
| 1162 | char tag_name[14]; |
| 1163 | unsigned int i_nlink; |
| 1164 | struct v9fs_session_info *v9ses = sb->s_fs_info; |
| 1165 | struct v9fs_inode *v9inode = V9FS_I(inode); |
| 1166 | |
| 1167 | set_nlink(inode, 1); |
| 1168 | |
| 1169 | inode->i_atime.tv_sec = stat->atime; |
| 1170 | inode->i_mtime.tv_sec = stat->mtime; |
| 1171 | inode->i_ctime.tv_sec = stat->mtime; |
| 1172 | |
| 1173 | inode->i_uid = v9ses->dfltuid; |
| 1174 | inode->i_gid = v9ses->dfltgid; |
| 1175 | |
| 1176 | if (v9fs_proto_dotu(v9ses)) { |
| 1177 | inode->i_uid = stat->n_uid; |
| 1178 | inode->i_gid = stat->n_gid; |
| 1179 | } |
| 1180 | if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) { |
| 1181 | if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) { |
| 1182 | /* |
| 1183 | * Hadlink support got added later to |
| 1184 | * to the .u extension. So there can be |
| 1185 | * server out there that doesn't support |
| 1186 | * this even with .u extension. So check |
| 1187 | * for non NULL stat->extension |
| 1188 | */ |
| 1189 | strlcpy(ext, stat->extension, sizeof(ext)); |
| 1190 | /* HARDLINKCOUNT %u */ |
| 1191 | sscanf(ext, "%13s %u", tag_name, &i_nlink); |
| 1192 | if (!strncmp(tag_name, "HARDLINKCOUNT", 13)) |
| 1193 | set_nlink(inode, i_nlink); |
| 1194 | } |
| 1195 | } |
| 1196 | mode = p9mode2perm(v9ses, stat); |
| 1197 | mode |= inode->i_mode & ~S_IALLUGO; |
| 1198 | inode->i_mode = mode; |
| 1199 | |
| 1200 | if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE)) |
| 1201 | v9fs_i_size_write(inode, stat->length); |
| 1202 | /* not real number of blocks, but 512 byte ones ... */ |
| 1203 | inode->i_blocks = (stat->length + 512 - 1) >> 9; |
| 1204 | v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR; |
| 1205 | } |
| 1206 | |
| 1207 | /** |
| 1208 | * v9fs_qid2ino - convert qid into inode number |
| 1209 | * @qid: qid to hash |
| 1210 | * |
| 1211 | * BUG: potential for inode number collisions? |
| 1212 | */ |
| 1213 | |
| 1214 | ino_t v9fs_qid2ino(struct p9_qid *qid) |
| 1215 | { |
| 1216 | u64 path = qid->path + 2; |
| 1217 | ino_t i = 0; |
| 1218 | |
| 1219 | if (sizeof(ino_t) == sizeof(path)) |
| 1220 | memcpy(&i, &path, sizeof(ino_t)); |
| 1221 | else |
| 1222 | i = (ino_t) (path ^ (path >> 32)); |
| 1223 | |
| 1224 | return i; |
| 1225 | } |
| 1226 | |
| 1227 | /** |
| 1228 | * v9fs_vfs_get_link - follow a symlink path |
| 1229 | * @dentry: dentry for symlink |
| 1230 | * @inode: inode for symlink |
| 1231 | * @done: delayed call for when we are done with the return value |
| 1232 | */ |
| 1233 | |
| 1234 | static const char *v9fs_vfs_get_link(struct dentry *dentry, |
| 1235 | struct inode *inode, |
| 1236 | struct delayed_call *done) |
| 1237 | { |
| 1238 | struct v9fs_session_info *v9ses; |
| 1239 | struct p9_fid *fid; |
| 1240 | struct p9_wstat *st; |
| 1241 | char *res; |
| 1242 | |
| 1243 | if (!dentry) |
| 1244 | return ERR_PTR(-ECHILD); |
| 1245 | |
| 1246 | v9ses = v9fs_dentry2v9ses(dentry); |
| 1247 | fid = v9fs_fid_lookup(dentry); |
| 1248 | p9_debug(P9_DEBUG_VFS, "%pd\n", dentry); |
| 1249 | |
| 1250 | if (IS_ERR(fid)) |
| 1251 | return ERR_CAST(fid); |
| 1252 | |
| 1253 | if (!v9fs_proto_dotu(v9ses)) |
| 1254 | return ERR_PTR(-EBADF); |
| 1255 | |
| 1256 | st = p9_client_stat(fid); |
| 1257 | if (IS_ERR(st)) |
| 1258 | return ERR_CAST(st); |
| 1259 | |
| 1260 | if (!(st->mode & P9_DMSYMLINK)) { |
| 1261 | p9stat_free(st); |
| 1262 | kfree(st); |
| 1263 | return ERR_PTR(-EINVAL); |
| 1264 | } |
| 1265 | res = st->extension; |
| 1266 | st->extension = NULL; |
| 1267 | if (strlen(res) >= PATH_MAX) |
| 1268 | res[PATH_MAX - 1] = '\0'; |
| 1269 | |
| 1270 | p9stat_free(st); |
| 1271 | kfree(st); |
| 1272 | set_delayed_call(done, kfree_link, res); |
| 1273 | return res; |
| 1274 | } |
| 1275 | |
| 1276 | /** |
| 1277 | * v9fs_vfs_mkspecial - create a special file |
| 1278 | * @dir: inode to create special file in |
| 1279 | * @dentry: dentry to create |
| 1280 | * @perm: mode to create special file |
| 1281 | * @extension: 9p2000.u format extension string representing special file |
| 1282 | * |
| 1283 | */ |
| 1284 | |
| 1285 | static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry, |
| 1286 | u32 perm, const char *extension) |
| 1287 | { |
| 1288 | struct p9_fid *fid; |
| 1289 | struct v9fs_session_info *v9ses; |
| 1290 | |
| 1291 | v9ses = v9fs_inode2v9ses(dir); |
| 1292 | if (!v9fs_proto_dotu(v9ses)) { |
| 1293 | p9_debug(P9_DEBUG_ERROR, "not extended\n"); |
| 1294 | return -EPERM; |
| 1295 | } |
| 1296 | |
| 1297 | fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm, |
| 1298 | P9_OREAD); |
| 1299 | if (IS_ERR(fid)) |
| 1300 | return PTR_ERR(fid); |
| 1301 | |
| 1302 | v9fs_invalidate_inode_attr(dir); |
| 1303 | p9_client_clunk(fid); |
| 1304 | return 0; |
| 1305 | } |
| 1306 | |
| 1307 | /** |
| 1308 | * v9fs_vfs_symlink - helper function to create symlinks |
| 1309 | * @dir: directory inode containing symlink |
| 1310 | * @dentry: dentry for symlink |
| 1311 | * @symname: symlink data |
| 1312 | * |
| 1313 | * See Also: 9P2000.u RFC for more information |
| 1314 | * |
| 1315 | */ |
| 1316 | |
| 1317 | static int |
| 1318 | v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) |
| 1319 | { |
| 1320 | p9_debug(P9_DEBUG_VFS, " %lu,%pd,%s\n", |
| 1321 | dir->i_ino, dentry, symname); |
| 1322 | |
| 1323 | return v9fs_vfs_mkspecial(dir, dentry, P9_DMSYMLINK, symname); |
| 1324 | } |
| 1325 | |
| 1326 | #define U32_MAX_DIGITS 10 |
| 1327 | |
| 1328 | /** |
| 1329 | * v9fs_vfs_link - create a hardlink |
| 1330 | * @old_dentry: dentry for file to link to |
| 1331 | * @dir: inode destination for new link |
| 1332 | * @dentry: dentry for link |
| 1333 | * |
| 1334 | */ |
| 1335 | |
| 1336 | static int |
| 1337 | v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir, |
| 1338 | struct dentry *dentry) |
| 1339 | { |
| 1340 | int retval; |
| 1341 | char name[1 + U32_MAX_DIGITS + 2]; /* sign + number + \n + \0 */ |
| 1342 | struct p9_fid *oldfid; |
| 1343 | |
| 1344 | p9_debug(P9_DEBUG_VFS, " %lu,%pd,%pd\n", |
| 1345 | dir->i_ino, dentry, old_dentry); |
| 1346 | |
| 1347 | oldfid = v9fs_fid_clone(old_dentry); |
| 1348 | if (IS_ERR(oldfid)) |
| 1349 | return PTR_ERR(oldfid); |
| 1350 | |
| 1351 | sprintf(name, "%d\n", oldfid->fid); |
| 1352 | retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name); |
| 1353 | if (!retval) { |
| 1354 | v9fs_refresh_inode(oldfid, d_inode(old_dentry)); |
| 1355 | v9fs_invalidate_inode_attr(dir); |
| 1356 | } |
| 1357 | p9_client_clunk(oldfid); |
| 1358 | return retval; |
| 1359 | } |
| 1360 | |
| 1361 | /** |
| 1362 | * v9fs_vfs_mknod - create a special file |
| 1363 | * @dir: inode destination for new link |
| 1364 | * @dentry: dentry for file |
| 1365 | * @mode: mode for creation |
| 1366 | * @rdev: device associated with special file |
| 1367 | * |
| 1368 | */ |
| 1369 | |
| 1370 | static int |
| 1371 | v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev) |
| 1372 | { |
| 1373 | struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir); |
| 1374 | int retval; |
| 1375 | char name[2 + U32_MAX_DIGITS + 1 + U32_MAX_DIGITS + 1]; |
| 1376 | u32 perm; |
| 1377 | |
| 1378 | p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %hx MAJOR: %u MINOR: %u\n", |
| 1379 | dir->i_ino, dentry, mode, |
| 1380 | MAJOR(rdev), MINOR(rdev)); |
| 1381 | |
| 1382 | /* build extension */ |
| 1383 | if (S_ISBLK(mode)) |
| 1384 | sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev)); |
| 1385 | else if (S_ISCHR(mode)) |
| 1386 | sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev)); |
| 1387 | else |
| 1388 | *name = 0; |
| 1389 | |
| 1390 | perm = unixmode2p9mode(v9ses, mode); |
| 1391 | retval = v9fs_vfs_mkspecial(dir, dentry, perm, name); |
| 1392 | |
| 1393 | return retval; |
| 1394 | } |
| 1395 | |
| 1396 | int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode) |
| 1397 | { |
| 1398 | int umode; |
| 1399 | dev_t rdev; |
| 1400 | struct p9_wstat *st; |
| 1401 | struct v9fs_session_info *v9ses; |
| 1402 | unsigned int flags; |
| 1403 | |
| 1404 | v9ses = v9fs_inode2v9ses(inode); |
| 1405 | st = p9_client_stat(fid); |
| 1406 | if (IS_ERR(st)) |
| 1407 | return PTR_ERR(st); |
| 1408 | /* |
| 1409 | * Don't update inode if the file type is different |
| 1410 | */ |
| 1411 | umode = p9mode2unixmode(v9ses, st, &rdev); |
| 1412 | if ((inode->i_mode & S_IFMT) != (umode & S_IFMT)) |
| 1413 | goto out; |
| 1414 | |
| 1415 | /* |
| 1416 | * We don't want to refresh inode->i_size, |
| 1417 | * because we may have cached data |
| 1418 | */ |
| 1419 | flags = (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) ? |
| 1420 | V9FS_STAT2INODE_KEEP_ISIZE : 0; |
| 1421 | v9fs_stat2inode(st, inode, inode->i_sb, flags); |
| 1422 | out: |
| 1423 | p9stat_free(st); |
| 1424 | kfree(st); |
| 1425 | return 0; |
| 1426 | } |
| 1427 | |
| 1428 | static const struct inode_operations v9fs_dir_inode_operations_dotu = { |
| 1429 | .create = v9fs_vfs_create, |
| 1430 | .lookup = v9fs_vfs_lookup, |
| 1431 | .atomic_open = v9fs_vfs_atomic_open, |
| 1432 | .symlink = v9fs_vfs_symlink, |
| 1433 | .link = v9fs_vfs_link, |
| 1434 | .unlink = v9fs_vfs_unlink, |
| 1435 | .mkdir = v9fs_vfs_mkdir, |
| 1436 | .rmdir = v9fs_vfs_rmdir, |
| 1437 | .mknod = v9fs_vfs_mknod, |
| 1438 | .rename = v9fs_vfs_rename, |
| 1439 | .getattr = v9fs_vfs_getattr, |
| 1440 | .setattr = v9fs_vfs_setattr, |
| 1441 | }; |
| 1442 | |
| 1443 | static const struct inode_operations v9fs_dir_inode_operations = { |
| 1444 | .create = v9fs_vfs_create, |
| 1445 | .lookup = v9fs_vfs_lookup, |
| 1446 | .atomic_open = v9fs_vfs_atomic_open, |
| 1447 | .unlink = v9fs_vfs_unlink, |
| 1448 | .mkdir = v9fs_vfs_mkdir, |
| 1449 | .rmdir = v9fs_vfs_rmdir, |
| 1450 | .mknod = v9fs_vfs_mknod, |
| 1451 | .rename = v9fs_vfs_rename, |
| 1452 | .getattr = v9fs_vfs_getattr, |
| 1453 | .setattr = v9fs_vfs_setattr, |
| 1454 | }; |
| 1455 | |
| 1456 | static const struct inode_operations v9fs_file_inode_operations = { |
| 1457 | .getattr = v9fs_vfs_getattr, |
| 1458 | .setattr = v9fs_vfs_setattr, |
| 1459 | }; |
| 1460 | |
| 1461 | static const struct inode_operations v9fs_symlink_inode_operations = { |
| 1462 | .get_link = v9fs_vfs_get_link, |
| 1463 | .getattr = v9fs_vfs_getattr, |
| 1464 | .setattr = v9fs_vfs_setattr, |
| 1465 | }; |
| 1466 | |