| 1 | /* $NetBSD: tmpfs_subr.c,v 1.35 2007/07/09 21:10:50 ad Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 2005 The NetBSD Foundation, Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to The NetBSD Foundation |
| 8 | * by Julio M. Merino Vidal, developed as part of Google's Summer of Code |
| 9 | * 2005 program. |
| 10 | * |
| 11 | * Redistribution and use in source and binary forms, with or without |
| 12 | * modification, are permitted provided that the following conditions |
| 13 | * are met: |
| 14 | * 1. Redistributions of source code must retain the above copyright |
| 15 | * notice, this list of conditions and the following disclaimer. |
| 16 | * 2. Redistributions in binary form must reproduce the above copyright |
| 17 | * notice, this list of conditions and the following disclaimer in the |
| 18 | * documentation and/or other materials provided with the distribution. |
| 19 | * |
| 20 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 21 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 22 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 23 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 24 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 25 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 26 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 27 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 28 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 29 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 30 | * POSSIBILITY OF SUCH DAMAGE. |
| 31 | */ |
| 32 | |
| 33 | /* |
| 34 | * Efficient memory file system supporting functions. |
| 35 | */ |
| 36 | |
| 37 | #include <sys/kernel.h> |
| 38 | #include <sys/param.h> |
| 39 | #include <sys/namei.h> |
| 40 | #include <sys/priv.h> |
| 41 | #include <sys/proc.h> |
| 42 | #include <sys/spinlock2.h> |
| 43 | #include <sys/stat.h> |
| 44 | #include <sys/systm.h> |
| 45 | #include <sys/vnode.h> |
| 46 | #include <sys/vmmeter.h> |
| 47 | |
| 48 | #include <vm/vm.h> |
| 49 | #include <vm/vm_object.h> |
| 50 | #include <vm/vm_page.h> |
| 51 | #include <vm/vm_pager.h> |
| 52 | #include <vm/vm_extern.h> |
| 53 | |
| 54 | #include <vfs/tmpfs/tmpfs.h> |
| 55 | #include <vfs/tmpfs/tmpfs_vnops.h> |
| 56 | |
| 57 | static ino_t tmpfs_fetch_ino(struct tmpfs_mount *); |
| 58 | static int tmpfs_dirtree_compare(struct tmpfs_dirent *a, |
| 59 | struct tmpfs_dirent *b); |
| 60 | |
| 61 | RB_GENERATE(tmpfs_dirtree, tmpfs_dirent, rb_node, tmpfs_dirtree_compare); |
| 62 | |
| 63 | |
| 64 | /* --------------------------------------------------------------------- */ |
| 65 | |
| 66 | /* |
| 67 | * Allocates a new node of type 'type' inside the 'tmp' mount point, with |
| 68 | * its owner set to 'uid', its group to 'gid' and its mode set to 'mode', |
| 69 | * using the credentials of the process 'p'. |
| 70 | * |
| 71 | * If the node type is set to 'VDIR', then the parent parameter must point |
| 72 | * to the parent directory of the node being created. It may only be NULL |
| 73 | * while allocating the root node. |
| 74 | * |
| 75 | * If the node type is set to 'VBLK' or 'VCHR', then the rdev parameter |
| 76 | * specifies the device the node represents. |
| 77 | * |
| 78 | * If the node type is set to 'VLNK', then the parameter target specifies |
| 79 | * the file name of the target file for the symbolic link that is being |
| 80 | * created. |
| 81 | * |
| 82 | * Note that new nodes are retrieved from the available list if it has |
| 83 | * items or, if it is empty, from the node pool as long as there is enough |
| 84 | * space to create them. |
| 85 | * |
| 86 | * Returns zero on success or an appropriate error code on failure. |
| 87 | */ |
| 88 | int |
| 89 | tmpfs_alloc_node(struct tmpfs_mount *tmp, enum vtype type, |
| 90 | uid_t uid, gid_t gid, mode_t mode, struct tmpfs_node *parent, |
| 91 | char *target, int rmajor, int rminor, struct tmpfs_node **node) |
| 92 | { |
| 93 | struct tmpfs_node *nnode; |
| 94 | struct timespec ts; |
| 95 | udev_t rdev; |
| 96 | |
| 97 | /* If the root directory of the 'tmp' file system is not yet |
| 98 | * allocated, this must be the request to do it. */ |
| 99 | KKASSERT(IMPLIES(tmp->tm_root == NULL, parent == NULL && type == VDIR)); |
| 100 | |
| 101 | KKASSERT(IFF(type == VLNK, target != NULL)); |
| 102 | KKASSERT(IFF(type == VBLK || type == VCHR, rmajor != VNOVAL)); |
| 103 | |
| 104 | if (tmp->tm_nodes_inuse >= tmp->tm_nodes_max) |
| 105 | return (ENOSPC); |
| 106 | |
| 107 | nnode = objcache_get(tmp->tm_node_pool, M_WAITOK | M_NULLOK); |
| 108 | if (nnode == NULL) |
| 109 | return (ENOSPC); |
| 110 | |
| 111 | /* Generic initialization. */ |
| 112 | nnode->tn_type = type; |
| 113 | vfs_timestamp(&ts); |
| 114 | nnode->tn_ctime = nnode->tn_mtime = nnode->tn_atime |
| 115 | = ts.tv_sec; |
| 116 | nnode->tn_ctimensec = nnode->tn_mtimensec = nnode->tn_atimensec |
| 117 | = ts.tv_nsec; |
| 118 | nnode->tn_uid = uid; |
| 119 | nnode->tn_gid = gid; |
| 120 | nnode->tn_mode = mode; |
| 121 | nnode->tn_id = tmpfs_fetch_ino(tmp); |
| 122 | nnode->tn_advlock.init_done = 0; |
| 123 | |
| 124 | /* Type-specific initialization. */ |
| 125 | switch (nnode->tn_type) { |
| 126 | case VBLK: |
| 127 | case VCHR: |
| 128 | rdev = makeudev(rmajor, rminor); |
| 129 | if (rdev == NOUDEV) { |
| 130 | objcache_put(tmp->tm_node_pool, nnode); |
| 131 | return(EINVAL); |
| 132 | } |
| 133 | nnode->tn_rdev = rdev; |
| 134 | break; |
| 135 | |
| 136 | case VDIR: |
| 137 | RB_INIT(&nnode->tn_dir.tn_dirtree); |
| 138 | KKASSERT(parent != nnode); |
| 139 | KKASSERT(IMPLIES(parent == NULL, tmp->tm_root == NULL)); |
| 140 | nnode->tn_dir.tn_parent = parent; |
| 141 | nnode->tn_dir.tn_readdir_lastn = 0; |
| 142 | nnode->tn_dir.tn_readdir_lastp = NULL; |
| 143 | nnode->tn_links++; |
| 144 | nnode->tn_size = 0; |
| 145 | if (parent) { |
| 146 | TMPFS_NODE_LOCK(parent); |
| 147 | parent->tn_links++; |
| 148 | TMPFS_NODE_UNLOCK(parent); |
| 149 | } |
| 150 | break; |
| 151 | |
| 152 | case VFIFO: |
| 153 | /* FALLTHROUGH */ |
| 154 | case VSOCK: |
| 155 | break; |
| 156 | |
| 157 | case VLNK: |
| 158 | nnode->tn_size = strlen(target); |
| 159 | nnode->tn_link = kmalloc(nnode->tn_size + 1, tmp->tm_name_zone, |
| 160 | M_WAITOK | M_NULLOK); |
| 161 | if (nnode->tn_link == NULL) { |
| 162 | objcache_put(tmp->tm_node_pool, nnode); |
| 163 | return (ENOSPC); |
| 164 | } |
| 165 | bcopy(target, nnode->tn_link, nnode->tn_size); |
| 166 | nnode->tn_link[nnode->tn_size] = '\0'; |
| 167 | break; |
| 168 | |
| 169 | case VREG: |
| 170 | nnode->tn_reg.tn_aobj = |
| 171 | swap_pager_alloc(NULL, 0, VM_PROT_DEFAULT, 0); |
| 172 | nnode->tn_reg.tn_aobj_pages = 0; |
| 173 | nnode->tn_size = 0; |
| 174 | break; |
| 175 | |
| 176 | default: |
| 177 | panic("tmpfs_alloc_node: type %p %d", nnode, (int)nnode->tn_type); |
| 178 | } |
| 179 | |
| 180 | TMPFS_NODE_LOCK(nnode); |
| 181 | TMPFS_LOCK(tmp); |
| 182 | LIST_INSERT_HEAD(&tmp->tm_nodes_used, nnode, tn_entries); |
| 183 | tmp->tm_nodes_inuse++; |
| 184 | TMPFS_UNLOCK(tmp); |
| 185 | TMPFS_NODE_UNLOCK(nnode); |
| 186 | |
| 187 | *node = nnode; |
| 188 | return 0; |
| 189 | } |
| 190 | |
| 191 | /* --------------------------------------------------------------------- */ |
| 192 | |
| 193 | /* |
| 194 | * Destroys the node pointed to by node from the file system 'tmp'. |
| 195 | * If the node does not belong to the given mount point, the results are |
| 196 | * unpredicted. |
| 197 | * |
| 198 | * If the node references a directory; no entries are allowed because |
| 199 | * their removal could need a recursive algorithm, something forbidden in |
| 200 | * kernel space. Furthermore, there is not need to provide such |
| 201 | * functionality (recursive removal) because the only primitives offered |
| 202 | * to the user are the removal of empty directories and the deletion of |
| 203 | * individual files. |
| 204 | * |
| 205 | * Note that nodes are not really deleted; in fact, when a node has been |
| 206 | * allocated, it cannot be deleted during the whole life of the file |
| 207 | * system. Instead, they are moved to the available list and remain there |
| 208 | * until reused. |
| 209 | */ |
| 210 | void |
| 211 | tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node) |
| 212 | { |
| 213 | vm_pindex_t pages = 0; |
| 214 | |
| 215 | #ifdef INVARIANTS |
| 216 | TMPFS_ASSERT_ELOCKED(node); |
| 217 | KKASSERT(node->tn_vnode == NULL); |
| 218 | KKASSERT((node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0); |
| 219 | #endif |
| 220 | |
| 221 | TMPFS_LOCK(tmp); |
| 222 | LIST_REMOVE(node, tn_entries); |
| 223 | tmp->tm_nodes_inuse--; |
| 224 | TMPFS_UNLOCK(tmp); |
| 225 | TMPFS_NODE_UNLOCK(node); |
| 226 | |
| 227 | switch (node->tn_type) { |
| 228 | case VNON: |
| 229 | /* Do not do anything. VNON is provided to let the |
| 230 | * allocation routine clean itself easily by avoiding |
| 231 | * duplicating code in it. */ |
| 232 | /* FALLTHROUGH */ |
| 233 | case VBLK: |
| 234 | /* FALLTHROUGH */ |
| 235 | case VCHR: |
| 236 | /* FALLTHROUGH */ |
| 237 | break; |
| 238 | case VDIR: |
| 239 | /* |
| 240 | * The parent link can be NULL if this is the root |
| 241 | * node. |
| 242 | */ |
| 243 | node->tn_links--; |
| 244 | node->tn_size = 0; |
| 245 | KKASSERT(node->tn_dir.tn_parent || node == tmp->tm_root); |
| 246 | if (node->tn_dir.tn_parent) { |
| 247 | TMPFS_NODE_LOCK(node->tn_dir.tn_parent); |
| 248 | node->tn_dir.tn_parent->tn_links--; |
| 249 | |
| 250 | /* |
| 251 | * If the parent directory has no more links and |
| 252 | * no vnode ref nothing is going to come along |
| 253 | * and clean it up unless we do it here. |
| 254 | */ |
| 255 | if (node->tn_dir.tn_parent->tn_links == 0 && |
| 256 | node->tn_dir.tn_parent->tn_vnode == NULL) { |
| 257 | tmpfs_free_node(tmp, node->tn_dir.tn_parent); |
| 258 | /* eats parent lock */ |
| 259 | } else { |
| 260 | TMPFS_NODE_UNLOCK(node->tn_dir.tn_parent); |
| 261 | } |
| 262 | node->tn_dir.tn_parent = NULL; |
| 263 | } |
| 264 | |
| 265 | /* |
| 266 | * If the root node is being destroyed don't leave a |
| 267 | * dangling pointer in tmpfs_mount. |
| 268 | */ |
| 269 | if (node == tmp->tm_root) |
| 270 | tmp->tm_root = NULL; |
| 271 | break; |
| 272 | case VFIFO: |
| 273 | /* FALLTHROUGH */ |
| 274 | case VSOCK: |
| 275 | break; |
| 276 | |
| 277 | case VLNK: |
| 278 | kfree(node->tn_link, tmp->tm_name_zone); |
| 279 | node->tn_link = NULL; |
| 280 | node->tn_size = 0; |
| 281 | break; |
| 282 | |
| 283 | case VREG: |
| 284 | if (node->tn_reg.tn_aobj != NULL) |
| 285 | vm_object_deallocate(node->tn_reg.tn_aobj); |
| 286 | node->tn_reg.tn_aobj = NULL; |
| 287 | pages = node->tn_reg.tn_aobj_pages; |
| 288 | break; |
| 289 | |
| 290 | default: |
| 291 | panic("tmpfs_free_node: type %p %d", node, (int)node->tn_type); |
| 292 | } |
| 293 | |
| 294 | /* |
| 295 | * Clean up fields for the next allocation. The objcache only ctors |
| 296 | * new allocations. |
| 297 | */ |
| 298 | tmpfs_node_ctor(node, NULL, 0); |
| 299 | objcache_put(tmp->tm_node_pool, node); |
| 300 | /* node is now invalid */ |
| 301 | |
| 302 | TMPFS_LOCK(tmp); |
| 303 | tmp->tm_pages_used -= pages; |
| 304 | TMPFS_UNLOCK(tmp); |
| 305 | } |
| 306 | |
| 307 | /* --------------------------------------------------------------------- */ |
| 308 | |
| 309 | /* |
| 310 | * Allocates a new directory entry for the node node with a name of name. |
| 311 | * The new directory entry is returned in *de. |
| 312 | * |
| 313 | * The link count of node is increased by one to reflect the new object |
| 314 | * referencing it. |
| 315 | * |
| 316 | * Returns zero on success or an appropriate error code on failure. |
| 317 | */ |
| 318 | int |
| 319 | tmpfs_alloc_dirent(struct tmpfs_mount *tmp, struct tmpfs_node *node, |
| 320 | const char *name, uint16_t len, struct tmpfs_dirent **de) |
| 321 | { |
| 322 | struct tmpfs_dirent *nde; |
| 323 | |
| 324 | nde = objcache_get(tmp->tm_dirent_pool, M_WAITOK); |
| 325 | nde->td_name = kmalloc(len + 1, tmp->tm_name_zone, M_WAITOK | M_NULLOK); |
| 326 | if (nde->td_name == NULL) { |
| 327 | objcache_put(tmp->tm_dirent_pool, nde); |
| 328 | *de = NULL; |
| 329 | return (ENOSPC); |
| 330 | } |
| 331 | nde->td_namelen = len; |
| 332 | bcopy(name, nde->td_name, len); |
| 333 | nde->td_name[len] = '\0'; |
| 334 | |
| 335 | nde->td_node = node; |
| 336 | |
| 337 | TMPFS_NODE_LOCK(node); |
| 338 | node->tn_links++; |
| 339 | TMPFS_NODE_UNLOCK(node); |
| 340 | |
| 341 | *de = nde; |
| 342 | |
| 343 | return 0; |
| 344 | } |
| 345 | |
| 346 | /* --------------------------------------------------------------------- */ |
| 347 | |
| 348 | /* |
| 349 | * Frees a directory entry. It is the caller's responsibility to destroy |
| 350 | * the node referenced by it if needed. |
| 351 | * |
| 352 | * The link count of node is decreased by one to reflect the removal of an |
| 353 | * object that referenced it. This only happens if 'node_exists' is true; |
| 354 | * otherwise the function will not access the node referred to by the |
| 355 | * directory entry, as it may already have been released from the outside. |
| 356 | */ |
| 357 | void |
| 358 | tmpfs_free_dirent(struct tmpfs_mount *tmp, struct tmpfs_dirent *de) |
| 359 | { |
| 360 | struct tmpfs_node *node; |
| 361 | |
| 362 | node = de->td_node; |
| 363 | |
| 364 | TMPFS_NODE_LOCK(node); |
| 365 | TMPFS_ASSERT_ELOCKED(node); |
| 366 | KKASSERT(node->tn_links > 0); |
| 367 | node->tn_links--; |
| 368 | TMPFS_NODE_UNLOCK(node); |
| 369 | |
| 370 | kfree(de->td_name, tmp->tm_name_zone); |
| 371 | de->td_namelen = 0; |
| 372 | de->td_name = NULL; |
| 373 | de->td_node = NULL; |
| 374 | objcache_put(tmp->tm_dirent_pool, de); |
| 375 | } |
| 376 | |
| 377 | /* --------------------------------------------------------------------- */ |
| 378 | |
| 379 | /* |
| 380 | * Allocates a new vnode for the node node or returns a new reference to |
| 381 | * an existing one if the node had already a vnode referencing it. The |
| 382 | * resulting locked vnode is returned in *vpp. |
| 383 | * |
| 384 | * Returns zero on success or an appropriate error code on failure. |
| 385 | */ |
| 386 | int |
| 387 | tmpfs_alloc_vp(struct mount *mp, struct tmpfs_node *node, int lkflag, |
| 388 | struct vnode **vpp) |
| 389 | { |
| 390 | int error = 0; |
| 391 | struct vnode *vp; |
| 392 | |
| 393 | loop: |
| 394 | /* |
| 395 | * Interlocked extraction from node. This can race many things. |
| 396 | * We have to get a soft reference on the vnode while we hold |
| 397 | * the node locked, then acquire it properly and check for races. |
| 398 | */ |
| 399 | TMPFS_NODE_LOCK(node); |
| 400 | if ((vp = node->tn_vnode) != NULL) { |
| 401 | KKASSERT((node->tn_vpstate & TMPFS_VNODE_DOOMED) == 0); |
| 402 | vhold_interlocked(vp); |
| 403 | TMPFS_NODE_UNLOCK(node); |
| 404 | |
| 405 | if (vget(vp, lkflag | LK_EXCLUSIVE) != 0) { |
| 406 | vdrop(vp); |
| 407 | goto loop; |
| 408 | } |
| 409 | if (node->tn_vnode != vp) { |
| 410 | vput(vp); |
| 411 | vdrop(vp); |
| 412 | goto loop; |
| 413 | } |
| 414 | vdrop(vp); |
| 415 | goto out; |
| 416 | } |
| 417 | /* vp is NULL */ |
| 418 | |
| 419 | /* |
| 420 | * This should never happen. |
| 421 | */ |
| 422 | if (node->tn_vpstate & TMPFS_VNODE_DOOMED) { |
| 423 | TMPFS_NODE_UNLOCK(node); |
| 424 | error = ENOENT; |
| 425 | goto out; |
| 426 | } |
| 427 | |
| 428 | /* |
| 429 | * Interlock against other calls to tmpfs_alloc_vp() trying to |
| 430 | * allocate and assign a vp to node. |
| 431 | */ |
| 432 | if (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) { |
| 433 | node->tn_vpstate |= TMPFS_VNODE_WANT; |
| 434 | error = tsleep(&node->tn_vpstate, PINTERLOCKED | PCATCH, |
| 435 | "tmpfs_alloc_vp", 0); |
| 436 | TMPFS_NODE_UNLOCK(node); |
| 437 | if (error) |
| 438 | return error; |
| 439 | goto loop; |
| 440 | } |
| 441 | node->tn_vpstate |= TMPFS_VNODE_ALLOCATING; |
| 442 | TMPFS_NODE_UNLOCK(node); |
| 443 | |
| 444 | /* |
| 445 | * Allocate a new vnode (may block). The ALLOCATING flag should |
| 446 | * prevent a race against someone else assigning node->tn_vnode. |
| 447 | */ |
| 448 | error = getnewvnode(VT_TMPFS, mp, &vp, VLKTIMEOUT, LK_CANRECURSE); |
| 449 | if (error != 0) |
| 450 | goto unlock; |
| 451 | |
| 452 | KKASSERT(node->tn_vnode == NULL); |
| 453 | KKASSERT(vp != NULL); |
| 454 | vp->v_data = node; |
| 455 | vp->v_type = node->tn_type; |
| 456 | |
| 457 | /* Type-specific initialization. */ |
| 458 | switch (node->tn_type) { |
| 459 | case VBLK: |
| 460 | /* FALLTHROUGH */ |
| 461 | case VCHR: |
| 462 | /* FALLTHROUGH */ |
| 463 | case VSOCK: |
| 464 | break; |
| 465 | case VREG: |
| 466 | vinitvmio(vp, node->tn_size, BMASK, -1); |
| 467 | break; |
| 468 | case VLNK: |
| 469 | break; |
| 470 | case VFIFO: |
| 471 | vp->v_ops = &mp->mnt_vn_fifo_ops; |
| 472 | break; |
| 473 | case VDIR: |
| 474 | break; |
| 475 | |
| 476 | default: |
| 477 | panic("tmpfs_alloc_vp: type %p %d", node, (int)node->tn_type); |
| 478 | } |
| 479 | |
| 480 | insmntque(vp, mp); |
| 481 | |
| 482 | unlock: |
| 483 | TMPFS_NODE_LOCK(node); |
| 484 | |
| 485 | KKASSERT(node->tn_vpstate & TMPFS_VNODE_ALLOCATING); |
| 486 | node->tn_vpstate &= ~TMPFS_VNODE_ALLOCATING; |
| 487 | node->tn_vnode = vp; |
| 488 | |
| 489 | if (node->tn_vpstate & TMPFS_VNODE_WANT) { |
| 490 | node->tn_vpstate &= ~TMPFS_VNODE_WANT; |
| 491 | TMPFS_NODE_UNLOCK(node); |
| 492 | wakeup(&node->tn_vpstate); |
| 493 | } else { |
| 494 | TMPFS_NODE_UNLOCK(node); |
| 495 | } |
| 496 | |
| 497 | out: |
| 498 | *vpp = vp; |
| 499 | |
| 500 | KKASSERT(IFF(error == 0, *vpp != NULL && vn_islocked(*vpp))); |
| 501 | #ifdef INVARIANTS |
| 502 | TMPFS_NODE_LOCK(node); |
| 503 | KKASSERT(*vpp == node->tn_vnode); |
| 504 | TMPFS_NODE_UNLOCK(node); |
| 505 | #endif |
| 506 | |
| 507 | return error; |
| 508 | } |
| 509 | |
| 510 | /* --------------------------------------------------------------------- */ |
| 511 | |
| 512 | /* |
| 513 | * Destroys the association between the vnode vp and the node it |
| 514 | * references. |
| 515 | */ |
| 516 | void |
| 517 | tmpfs_free_vp(struct vnode *vp) |
| 518 | { |
| 519 | struct tmpfs_node *node; |
| 520 | |
| 521 | node = VP_TO_TMPFS_NODE(vp); |
| 522 | |
| 523 | TMPFS_NODE_LOCK(node); |
| 524 | KKASSERT(lockcount(TMPFS_NODE_MTX(node)) > 0); |
| 525 | node->tn_vnode = NULL; |
| 526 | TMPFS_NODE_UNLOCK(node); |
| 527 | vp->v_data = NULL; |
| 528 | } |
| 529 | |
| 530 | /* --------------------------------------------------------------------- */ |
| 531 | |
| 532 | /* |
| 533 | * Allocates a new file of type 'type' and adds it to the parent directory |
| 534 | * 'dvp'; this addition is done using the component name given in 'cnp'. |
| 535 | * The ownership of the new file is automatically assigned based on the |
| 536 | * credentials of the caller (through 'cnp'), the group is set based on |
| 537 | * the parent directory and the mode is determined from the 'vap' argument. |
| 538 | * If successful, *vpp holds a vnode to the newly created file and zero |
| 539 | * is returned. Otherwise *vpp is NULL and the function returns an |
| 540 | * appropriate error code. |
| 541 | */ |
| 542 | int |
| 543 | tmpfs_alloc_file(struct vnode *dvp, struct vnode **vpp, struct vattr *vap, |
| 544 | struct namecache *ncp, struct ucred *cred, char *target) |
| 545 | { |
| 546 | int error; |
| 547 | struct tmpfs_dirent *de; |
| 548 | struct tmpfs_mount *tmp; |
| 549 | struct tmpfs_node *dnode; |
| 550 | struct tmpfs_node *node; |
| 551 | struct tmpfs_node *parent; |
| 552 | |
| 553 | tmp = VFS_TO_TMPFS(dvp->v_mount); |
| 554 | dnode = VP_TO_TMPFS_DIR(dvp); |
| 555 | *vpp = NULL; |
| 556 | |
| 557 | /* If the entry we are creating is a directory, we cannot overflow |
| 558 | * the number of links of its parent, because it will get a new |
| 559 | * link. */ |
| 560 | if (vap->va_type == VDIR) { |
| 561 | /* Ensure that we do not overflow the maximum number of links |
| 562 | * imposed by the system. */ |
| 563 | KKASSERT(dnode->tn_links <= LINK_MAX); |
| 564 | if (dnode->tn_links == LINK_MAX) { |
| 565 | return EMLINK; |
| 566 | } |
| 567 | |
| 568 | parent = dnode; |
| 569 | KKASSERT(parent != NULL); |
| 570 | } else |
| 571 | parent = NULL; |
| 572 | |
| 573 | /* Allocate a node that represents the new file. */ |
| 574 | error = tmpfs_alloc_node(tmp, vap->va_type, cred->cr_uid, |
| 575 | dnode->tn_gid, vap->va_mode, parent, target, vap->va_rmajor, vap->va_rminor, &node); |
| 576 | if (error != 0) |
| 577 | return error; |
| 578 | TMPFS_NODE_LOCK(node); |
| 579 | |
| 580 | /* Allocate a directory entry that points to the new file. */ |
| 581 | error = tmpfs_alloc_dirent(tmp, node, ncp->nc_name, ncp->nc_nlen, &de); |
| 582 | if (error != 0) { |
| 583 | tmpfs_free_node(tmp, node); |
| 584 | /* eats node lock */ |
| 585 | return error; |
| 586 | } |
| 587 | |
| 588 | /* Allocate a vnode for the new file. */ |
| 589 | error = tmpfs_alloc_vp(dvp->v_mount, node, LK_EXCLUSIVE, vpp); |
| 590 | if (error != 0) { |
| 591 | tmpfs_free_dirent(tmp, de); |
| 592 | tmpfs_free_node(tmp, node); |
| 593 | /* eats node lock */ |
| 594 | return error; |
| 595 | } |
| 596 | |
| 597 | /* Now that all required items are allocated, we can proceed to |
| 598 | * insert the new node into the directory, an operation that |
| 599 | * cannot fail. */ |
| 600 | tmpfs_dir_attach(dnode, de); |
| 601 | TMPFS_NODE_UNLOCK(node); |
| 602 | |
| 603 | return error; |
| 604 | } |
| 605 | |
| 606 | /* --------------------------------------------------------------------- */ |
| 607 | |
| 608 | /* |
| 609 | * Attaches the directory entry de to the directory represented by vp. |
| 610 | * Note that this does not change the link count of the node pointed by |
| 611 | * the directory entry, as this is done by tmpfs_alloc_dirent. |
| 612 | */ |
| 613 | void |
| 614 | tmpfs_dir_attach(struct tmpfs_node *dnode, struct tmpfs_dirent *de) |
| 615 | { |
| 616 | TMPFS_NODE_LOCK(dnode); |
| 617 | RB_INSERT(tmpfs_dirtree, &dnode->tn_dir.tn_dirtree, de); |
| 618 | |
| 619 | TMPFS_ASSERT_ELOCKED(dnode); |
| 620 | dnode->tn_size += sizeof(struct tmpfs_dirent); |
| 621 | dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED | |
| 622 | TMPFS_NODE_MODIFIED; |
| 623 | TMPFS_NODE_UNLOCK(dnode); |
| 624 | } |
| 625 | |
| 626 | /* --------------------------------------------------------------------- */ |
| 627 | |
| 628 | /* |
| 629 | * Detaches the directory entry de from the directory represented by vp. |
| 630 | * Note that this does not change the link count of the node pointed by |
| 631 | * the directory entry, as this is done by tmpfs_free_dirent. |
| 632 | */ |
| 633 | void |
| 634 | tmpfs_dir_detach(struct tmpfs_node *dnode, struct tmpfs_dirent *de) |
| 635 | { |
| 636 | TMPFS_NODE_LOCK(dnode); |
| 637 | if (dnode->tn_dir.tn_readdir_lastp == de) { |
| 638 | dnode->tn_dir.tn_readdir_lastn = 0; |
| 639 | dnode->tn_dir.tn_readdir_lastp = NULL; |
| 640 | } |
| 641 | RB_REMOVE(tmpfs_dirtree, &dnode->tn_dir.tn_dirtree, de); |
| 642 | |
| 643 | TMPFS_ASSERT_ELOCKED(dnode); |
| 644 | dnode->tn_size -= sizeof(struct tmpfs_dirent); |
| 645 | dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED | |
| 646 | TMPFS_NODE_MODIFIED; |
| 647 | TMPFS_NODE_UNLOCK(dnode); |
| 648 | } |
| 649 | |
| 650 | /* --------------------------------------------------------------------- */ |
| 651 | |
| 652 | /* |
| 653 | * Looks for a directory entry in the directory represented by node. |
| 654 | * 'ncp' describes the name of the entry to look for. Note that the . |
| 655 | * and .. components are not allowed as they do not physically exist |
| 656 | * within directories. |
| 657 | * |
| 658 | * Returns a pointer to the entry when found, otherwise NULL. |
| 659 | */ |
| 660 | struct tmpfs_dirent * |
| 661 | tmpfs_dir_lookup(struct tmpfs_node *node, struct tmpfs_node *f, |
| 662 | struct namecache *ncp) |
| 663 | { |
| 664 | struct tmpfs_dirent *de; |
| 665 | int len = ncp->nc_nlen; |
| 666 | struct tmpfs_dirent wanted; |
| 667 | |
| 668 | wanted.td_namelen = len; |
| 669 | wanted.td_name = ncp->nc_name; |
| 670 | |
| 671 | TMPFS_VALIDATE_DIR(node); |
| 672 | |
| 673 | de = RB_FIND(tmpfs_dirtree, &node->tn_dir.tn_dirtree, &wanted); |
| 674 | |
| 675 | KKASSERT(f == NULL || f == de->td_node); |
| 676 | |
| 677 | TMPFS_NODE_LOCK(node); |
| 678 | node->tn_status |= TMPFS_NODE_ACCESSED; |
| 679 | TMPFS_NODE_UNLOCK(node); |
| 680 | |
| 681 | return de; |
| 682 | } |
| 683 | |
| 684 | /* --------------------------------------------------------------------- */ |
| 685 | |
| 686 | /* |
| 687 | * Helper function for tmpfs_readdir. Creates a '.' entry for the given |
| 688 | * directory and returns it in the uio space. The function returns 0 |
| 689 | * on success, -1 if there was not enough space in the uio structure to |
| 690 | * hold the directory entry or an appropriate error code if another |
| 691 | * error happens. |
| 692 | */ |
| 693 | int |
| 694 | tmpfs_dir_getdotdent(struct tmpfs_node *node, struct uio *uio) |
| 695 | { |
| 696 | int error; |
| 697 | struct dirent dent; |
| 698 | int dirsize; |
| 699 | |
| 700 | TMPFS_VALIDATE_DIR(node); |
| 701 | KKASSERT(uio->uio_offset == TMPFS_DIRCOOKIE_DOT); |
| 702 | |
| 703 | dent.d_ino = node->tn_id; |
| 704 | dent.d_type = DT_DIR; |
| 705 | dent.d_namlen = 1; |
| 706 | dent.d_name[0] = '.'; |
| 707 | dent.d_name[1] = '\0'; |
| 708 | dirsize = _DIRENT_DIRSIZ(&dent); |
| 709 | |
| 710 | if (dirsize > uio->uio_resid) |
| 711 | error = -1; |
| 712 | else { |
| 713 | error = uiomove((caddr_t)&dent, dirsize, uio); |
| 714 | if (error == 0) |
| 715 | uio->uio_offset = TMPFS_DIRCOOKIE_DOTDOT; |
| 716 | } |
| 717 | |
| 718 | TMPFS_NODE_LOCK(node); |
| 719 | node->tn_status |= TMPFS_NODE_ACCESSED; |
| 720 | TMPFS_NODE_UNLOCK(node); |
| 721 | |
| 722 | return error; |
| 723 | } |
| 724 | |
| 725 | /* --------------------------------------------------------------------- */ |
| 726 | |
| 727 | /* |
| 728 | * Helper function for tmpfs_readdir. Creates a '..' entry for the given |
| 729 | * directory and returns it in the uio space. The function returns 0 |
| 730 | * on success, -1 if there was not enough space in the uio structure to |
| 731 | * hold the directory entry or an appropriate error code if another |
| 732 | * error happens. |
| 733 | */ |
| 734 | int |
| 735 | tmpfs_dir_getdotdotdent(struct tmpfs_mount *tmp, struct tmpfs_node *node, |
| 736 | struct uio *uio) |
| 737 | { |
| 738 | int error; |
| 739 | struct dirent dent; |
| 740 | int dirsize; |
| 741 | |
| 742 | TMPFS_VALIDATE_DIR(node); |
| 743 | KKASSERT(uio->uio_offset == TMPFS_DIRCOOKIE_DOTDOT); |
| 744 | |
| 745 | if (node->tn_dir.tn_parent) { |
| 746 | TMPFS_NODE_LOCK(node->tn_dir.tn_parent); |
| 747 | dent.d_ino = node->tn_dir.tn_parent->tn_id; |
| 748 | TMPFS_NODE_UNLOCK(node->tn_dir.tn_parent); |
| 749 | } else { |
| 750 | dent.d_ino = tmp->tm_root->tn_id; |
| 751 | } |
| 752 | |
| 753 | dent.d_type = DT_DIR; |
| 754 | dent.d_namlen = 2; |
| 755 | dent.d_name[0] = '.'; |
| 756 | dent.d_name[1] = '.'; |
| 757 | dent.d_name[2] = '\0'; |
| 758 | dirsize = _DIRENT_DIRSIZ(&dent); |
| 759 | |
| 760 | if (dirsize > uio->uio_resid) |
| 761 | error = -1; |
| 762 | else { |
| 763 | error = uiomove((caddr_t)&dent, dirsize, uio); |
| 764 | if (error == 0) { |
| 765 | struct tmpfs_dirent *de; |
| 766 | |
| 767 | de = RB_MIN(tmpfs_dirtree, &node->tn_dir.tn_dirtree); |
| 768 | if (de == NULL) |
| 769 | uio->uio_offset = TMPFS_DIRCOOKIE_EOF; |
| 770 | else |
| 771 | uio->uio_offset = tmpfs_dircookie(de); |
| 772 | } |
| 773 | } |
| 774 | |
| 775 | TMPFS_NODE_LOCK(node); |
| 776 | node->tn_status |= TMPFS_NODE_ACCESSED; |
| 777 | TMPFS_NODE_UNLOCK(node); |
| 778 | |
| 779 | return error; |
| 780 | } |
| 781 | |
| 782 | /* --------------------------------------------------------------------- */ |
| 783 | |
| 784 | /* |
| 785 | * Lookup a directory entry by its associated cookie. |
| 786 | */ |
| 787 | struct tmpfs_dirent * |
| 788 | tmpfs_dir_lookupbycookie(struct tmpfs_node *node, off_t cookie) |
| 789 | { |
| 790 | struct tmpfs_dirent *de; |
| 791 | |
| 792 | if (cookie == node->tn_dir.tn_readdir_lastn && |
| 793 | node->tn_dir.tn_readdir_lastp != NULL) { |
| 794 | return node->tn_dir.tn_readdir_lastp; |
| 795 | } |
| 796 | |
| 797 | RB_FOREACH(de, tmpfs_dirtree, &node->tn_dir.tn_dirtree) { |
| 798 | if (tmpfs_dircookie(de) == cookie) { |
| 799 | break; |
| 800 | } |
| 801 | } |
| 802 | |
| 803 | return de; |
| 804 | } |
| 805 | |
| 806 | /* --------------------------------------------------------------------- */ |
| 807 | |
| 808 | /* |
| 809 | * Helper function for tmpfs_readdir. Returns as much directory entries |
| 810 | * as can fit in the uio space. The read starts at uio->uio_offset. |
| 811 | * The function returns 0 on success, -1 if there was not enough space |
| 812 | * in the uio structure to hold the directory entry or an appropriate |
| 813 | * error code if another error happens. |
| 814 | */ |
| 815 | int |
| 816 | tmpfs_dir_getdents(struct tmpfs_node *node, struct uio *uio, off_t *cntp) |
| 817 | { |
| 818 | int error; |
| 819 | off_t startcookie; |
| 820 | struct tmpfs_dirent *de; |
| 821 | |
| 822 | TMPFS_VALIDATE_DIR(node); |
| 823 | |
| 824 | /* Locate the first directory entry we have to return. We have cached |
| 825 | * the last readdir in the node, so use those values if appropriate. |
| 826 | * Otherwise do a linear scan to find the requested entry. */ |
| 827 | startcookie = uio->uio_offset; |
| 828 | KKASSERT(startcookie != TMPFS_DIRCOOKIE_DOT); |
| 829 | KKASSERT(startcookie != TMPFS_DIRCOOKIE_DOTDOT); |
| 830 | if (startcookie == TMPFS_DIRCOOKIE_EOF) { |
| 831 | return 0; |
| 832 | } else { |
| 833 | de = tmpfs_dir_lookupbycookie(node, startcookie); |
| 834 | } |
| 835 | if (de == NULL) { |
| 836 | return EINVAL; |
| 837 | } |
| 838 | |
| 839 | /* Read as much entries as possible; i.e., until we reach the end of |
| 840 | * the directory or we exhaust uio space. */ |
| 841 | do { |
| 842 | struct dirent d; |
| 843 | int reclen; |
| 844 | |
| 845 | /* Create a dirent structure representing the current |
| 846 | * tmpfs_node and fill it. */ |
| 847 | d.d_ino = de->td_node->tn_id; |
| 848 | switch (de->td_node->tn_type) { |
| 849 | case VBLK: |
| 850 | d.d_type = DT_BLK; |
| 851 | break; |
| 852 | |
| 853 | case VCHR: |
| 854 | d.d_type = DT_CHR; |
| 855 | break; |
| 856 | |
| 857 | case VDIR: |
| 858 | d.d_type = DT_DIR; |
| 859 | break; |
| 860 | |
| 861 | case VFIFO: |
| 862 | d.d_type = DT_FIFO; |
| 863 | break; |
| 864 | |
| 865 | case VLNK: |
| 866 | d.d_type = DT_LNK; |
| 867 | break; |
| 868 | |
| 869 | case VREG: |
| 870 | d.d_type = DT_REG; |
| 871 | break; |
| 872 | |
| 873 | case VSOCK: |
| 874 | d.d_type = DT_SOCK; |
| 875 | break; |
| 876 | |
| 877 | default: |
| 878 | panic("tmpfs_dir_getdents: type %p %d", |
| 879 | de->td_node, (int)de->td_node->tn_type); |
| 880 | } |
| 881 | d.d_namlen = de->td_namelen; |
| 882 | KKASSERT(de->td_namelen < sizeof(d.d_name)); |
| 883 | bcopy(de->td_name, d.d_name, d.d_namlen); |
| 884 | d.d_name[d.d_namlen] = '\0'; |
| 885 | reclen = _DIRENT_RECLEN(d.d_namlen); |
| 886 | |
| 887 | /* Stop reading if the directory entry we are treating is |
| 888 | * bigger than the amount of data that can be returned. */ |
| 889 | if (reclen > uio->uio_resid) { |
| 890 | error = -1; |
| 891 | break; |
| 892 | } |
| 893 | |
| 894 | /* Copy the new dirent structure into the output buffer and |
| 895 | * advance pointers. */ |
| 896 | error = uiomove((caddr_t)&d, reclen, uio); |
| 897 | |
| 898 | (*cntp)++; |
| 899 | de = RB_NEXT(tmpfs_dirtree, node->tn_dir.tn_dirtree, de); |
| 900 | } while (error == 0 && uio->uio_resid > 0 && de != NULL); |
| 901 | |
| 902 | /* Update the offset and cache. */ |
| 903 | if (de == NULL) { |
| 904 | uio->uio_offset = TMPFS_DIRCOOKIE_EOF; |
| 905 | node->tn_dir.tn_readdir_lastn = 0; |
| 906 | node->tn_dir.tn_readdir_lastp = NULL; |
| 907 | } else { |
| 908 | node->tn_dir.tn_readdir_lastn = uio->uio_offset = tmpfs_dircookie(de); |
| 909 | node->tn_dir.tn_readdir_lastp = de; |
| 910 | } |
| 911 | node->tn_status |= TMPFS_NODE_ACCESSED; |
| 912 | |
| 913 | return error; |
| 914 | } |
| 915 | |
| 916 | /* --------------------------------------------------------------------- */ |
| 917 | |
| 918 | /* |
| 919 | * Resizes the aobj associated to the regular file pointed to by vp to |
| 920 | * the size newsize. 'vp' must point to a vnode that represents a regular |
| 921 | * file. 'newsize' must be positive. |
| 922 | * |
| 923 | * pass trivial as 1 when buf content will be overwritten, otherwise set 0 |
| 924 | * to be zero filled. |
| 925 | * |
| 926 | * Returns zero on success or an appropriate error code on failure. |
| 927 | */ |
| 928 | int |
| 929 | tmpfs_reg_resize(struct vnode *vp, off_t newsize, int trivial) |
| 930 | { |
| 931 | int error; |
| 932 | vm_pindex_t newpages, oldpages; |
| 933 | struct tmpfs_mount *tmp; |
| 934 | struct tmpfs_node *node; |
| 935 | off_t oldsize; |
| 936 | |
| 937 | #ifdef INVARIANTS |
| 938 | KKASSERT(vp->v_type == VREG); |
| 939 | KKASSERT(newsize >= 0); |
| 940 | #endif |
| 941 | |
| 942 | node = VP_TO_TMPFS_NODE(vp); |
| 943 | tmp = VFS_TO_TMPFS(vp->v_mount); |
| 944 | |
| 945 | /* Convert the old and new sizes to the number of pages needed to |
| 946 | * store them. It may happen that we do not need to do anything |
| 947 | * because the last allocated page can accommodate the change on |
| 948 | * its own. */ |
| 949 | oldsize = node->tn_size; |
| 950 | oldpages = round_page64(oldsize) / PAGE_SIZE; |
| 951 | KKASSERT(oldpages == node->tn_reg.tn_aobj_pages); |
| 952 | newpages = round_page64(newsize) / PAGE_SIZE; |
| 953 | |
| 954 | if (newpages > oldpages && |
| 955 | tmp->tm_pages_used + newpages - oldpages > tmp->tm_pages_max) { |
| 956 | error = ENOSPC; |
| 957 | goto out; |
| 958 | } |
| 959 | |
| 960 | TMPFS_LOCK(tmp); |
| 961 | tmp->tm_pages_used += (newpages - oldpages); |
| 962 | TMPFS_UNLOCK(tmp); |
| 963 | |
| 964 | TMPFS_NODE_LOCK(node); |
| 965 | node->tn_reg.tn_aobj_pages = newpages; |
| 966 | node->tn_size = newsize; |
| 967 | TMPFS_NODE_UNLOCK(node); |
| 968 | |
| 969 | /* |
| 970 | * When adjusting the vnode filesize and its VM object we must |
| 971 | * also adjust our backing VM object (aobj). The blocksize |
| 972 | * used must match the block sized we use for the buffer cache. |
| 973 | * |
| 974 | * The backing VM object contains no VM pages, only swap |
| 975 | * assignments. |
| 976 | */ |
| 977 | if (newsize < oldsize) { |
| 978 | vm_pindex_t osize; |
| 979 | vm_pindex_t nsize; |
| 980 | vm_object_t aobj; |
| 981 | |
| 982 | error = nvtruncbuf(vp, newsize, BSIZE, -1, 0); |
| 983 | aobj = node->tn_reg.tn_aobj; |
| 984 | if (aobj) { |
| 985 | osize = aobj->size; |
| 986 | nsize = vp->v_object->size; |
| 987 | if (nsize < osize) { |
| 988 | aobj->size = osize; |
| 989 | swap_pager_freespace(aobj, nsize, |
| 990 | osize - nsize); |
| 991 | } |
| 992 | } |
| 993 | } else { |
| 994 | vm_object_t aobj; |
| 995 | |
| 996 | error = nvextendbuf(vp, oldsize, newsize, BSIZE, BSIZE, |
| 997 | -1, -1, trivial); |
| 998 | aobj = node->tn_reg.tn_aobj; |
| 999 | if (aobj) |
| 1000 | aobj->size = vp->v_object->size; |
| 1001 | } |
| 1002 | |
| 1003 | out: |
| 1004 | return error; |
| 1005 | } |
| 1006 | |
| 1007 | /* --------------------------------------------------------------------- */ |
| 1008 | |
| 1009 | /* |
| 1010 | * Change flags of the given vnode. |
| 1011 | * Caller should execute tmpfs_update on vp after a successful execution. |
| 1012 | * The vnode must be locked on entry and remain locked on exit. |
| 1013 | */ |
| 1014 | int |
| 1015 | tmpfs_chflags(struct vnode *vp, int vaflags, struct ucred *cred) |
| 1016 | { |
| 1017 | int error; |
| 1018 | struct tmpfs_node *node; |
| 1019 | int flags; |
| 1020 | |
| 1021 | KKASSERT(vn_islocked(vp)); |
| 1022 | |
| 1023 | node = VP_TO_TMPFS_NODE(vp); |
| 1024 | flags = node->tn_flags; |
| 1025 | |
| 1026 | /* Disallow this operation if the file system is mounted read-only. */ |
| 1027 | if (vp->v_mount->mnt_flag & MNT_RDONLY) |
| 1028 | return EROFS; |
| 1029 | error = vop_helper_setattr_flags(&flags, vaflags, node->tn_uid, cred); |
| 1030 | |
| 1031 | /* |
| 1032 | * Unprivileged processes are not permitted to unset system |
| 1033 | * flags, or modify flags if any system flags are set. |
| 1034 | * |
| 1035 | * Silently enforce SF_NOCACHE on the root tmpfs vnode so |
| 1036 | * tmpfs data is not double-cached by swapcache. |
| 1037 | */ |
| 1038 | if (error == 0) { |
| 1039 | TMPFS_NODE_LOCK(node); |
| 1040 | if (!priv_check_cred(cred, PRIV_VFS_SYSFLAGS, 0)) { |
| 1041 | if (vp->v_flag & VROOT) |
| 1042 | flags |= SF_NOCACHE; |
| 1043 | node->tn_flags = flags; |
| 1044 | } else { |
| 1045 | if (node->tn_flags & (SF_NOUNLINK | SF_IMMUTABLE | |
| 1046 | SF_APPEND) || |
| 1047 | (flags & UF_SETTABLE) != flags) { |
| 1048 | error = EPERM; |
| 1049 | } else { |
| 1050 | node->tn_flags &= SF_SETTABLE; |
| 1051 | node->tn_flags |= (flags & UF_SETTABLE); |
| 1052 | } |
| 1053 | } |
| 1054 | node->tn_status |= TMPFS_NODE_CHANGED; |
| 1055 | TMPFS_NODE_UNLOCK(node); |
| 1056 | } |
| 1057 | |
| 1058 | KKASSERT(vn_islocked(vp)); |
| 1059 | |
| 1060 | return error; |
| 1061 | } |
| 1062 | |
| 1063 | /* --------------------------------------------------------------------- */ |
| 1064 | |
| 1065 | /* |
| 1066 | * Change access mode on the given vnode. |
| 1067 | * Caller should execute tmpfs_update on vp after a successful execution. |
| 1068 | * The vnode must be locked on entry and remain locked on exit. |
| 1069 | */ |
| 1070 | int |
| 1071 | tmpfs_chmod(struct vnode *vp, mode_t vamode, struct ucred *cred) |
| 1072 | { |
| 1073 | struct tmpfs_node *node; |
| 1074 | mode_t cur_mode; |
| 1075 | int error; |
| 1076 | |
| 1077 | KKASSERT(vn_islocked(vp)); |
| 1078 | |
| 1079 | node = VP_TO_TMPFS_NODE(vp); |
| 1080 | |
| 1081 | /* Disallow this operation if the file system is mounted read-only. */ |
| 1082 | if (vp->v_mount->mnt_flag & MNT_RDONLY) |
| 1083 | return EROFS; |
| 1084 | |
| 1085 | /* Immutable or append-only files cannot be modified, either. */ |
| 1086 | if (node->tn_flags & (IMMUTABLE | APPEND)) |
| 1087 | return EPERM; |
| 1088 | |
| 1089 | cur_mode = node->tn_mode; |
| 1090 | error = vop_helper_chmod(vp, vamode, cred, node->tn_uid, node->tn_gid, |
| 1091 | &cur_mode); |
| 1092 | |
| 1093 | if (error == 0 && |
| 1094 | (node->tn_mode & ALLPERMS) != (cur_mode & ALLPERMS)) { |
| 1095 | TMPFS_NODE_LOCK(node); |
| 1096 | node->tn_mode &= ~ALLPERMS; |
| 1097 | node->tn_mode |= cur_mode & ALLPERMS; |
| 1098 | |
| 1099 | node->tn_status |= TMPFS_NODE_CHANGED; |
| 1100 | TMPFS_NODE_UNLOCK(node); |
| 1101 | } |
| 1102 | |
| 1103 | KKASSERT(vn_islocked(vp)); |
| 1104 | |
| 1105 | return 0; |
| 1106 | } |
| 1107 | |
| 1108 | /* --------------------------------------------------------------------- */ |
| 1109 | |
| 1110 | /* |
| 1111 | * Change ownership of the given vnode. At least one of uid or gid must |
| 1112 | * be different than VNOVAL. If one is set to that value, the attribute |
| 1113 | * is unchanged. |
| 1114 | * Caller should execute tmpfs_update on vp after a successful execution. |
| 1115 | * The vnode must be locked on entry and remain locked on exit. |
| 1116 | */ |
| 1117 | int |
| 1118 | tmpfs_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred) |
| 1119 | { |
| 1120 | mode_t cur_mode; |
| 1121 | uid_t cur_uid; |
| 1122 | gid_t cur_gid; |
| 1123 | struct tmpfs_node *node; |
| 1124 | int error; |
| 1125 | |
| 1126 | KKASSERT(vn_islocked(vp)); |
| 1127 | node = VP_TO_TMPFS_NODE(vp); |
| 1128 | |
| 1129 | /* Disallow this operation if the file system is mounted read-only. */ |
| 1130 | if (vp->v_mount->mnt_flag & MNT_RDONLY) |
| 1131 | return EROFS; |
| 1132 | |
| 1133 | /* Immutable or append-only files cannot be modified, either. */ |
| 1134 | if (node->tn_flags & (IMMUTABLE | APPEND)) |
| 1135 | return EPERM; |
| 1136 | |
| 1137 | cur_uid = node->tn_uid; |
| 1138 | cur_gid = node->tn_gid; |
| 1139 | cur_mode = node->tn_mode; |
| 1140 | error = vop_helper_chown(vp, uid, gid, cred, |
| 1141 | &cur_uid, &cur_gid, &cur_mode); |
| 1142 | |
| 1143 | if (error == 0) { |
| 1144 | TMPFS_NODE_LOCK(node); |
| 1145 | if (cur_uid != node->tn_uid || |
| 1146 | cur_gid != node->tn_gid || |
| 1147 | cur_mode != node->tn_mode) { |
| 1148 | node->tn_uid = cur_uid; |
| 1149 | node->tn_gid = cur_gid; |
| 1150 | node->tn_mode = cur_mode; |
| 1151 | node->tn_status |= TMPFS_NODE_CHANGED; |
| 1152 | } |
| 1153 | TMPFS_NODE_UNLOCK(node); |
| 1154 | } |
| 1155 | |
| 1156 | return error; |
| 1157 | } |
| 1158 | |
| 1159 | /* --------------------------------------------------------------------- */ |
| 1160 | |
| 1161 | /* |
| 1162 | * Change size of the given vnode. |
| 1163 | * Caller should execute tmpfs_update on vp after a successful execution. |
| 1164 | * The vnode must be locked on entry and remain locked on exit. |
| 1165 | */ |
| 1166 | int |
| 1167 | tmpfs_chsize(struct vnode *vp, u_quad_t size, struct ucred *cred) |
| 1168 | { |
| 1169 | int error; |
| 1170 | struct tmpfs_node *node; |
| 1171 | |
| 1172 | KKASSERT(vn_islocked(vp)); |
| 1173 | |
| 1174 | node = VP_TO_TMPFS_NODE(vp); |
| 1175 | |
| 1176 | /* Decide whether this is a valid operation based on the file type. */ |
| 1177 | error = 0; |
| 1178 | switch (vp->v_type) { |
| 1179 | case VDIR: |
| 1180 | return EISDIR; |
| 1181 | |
| 1182 | case VREG: |
| 1183 | if (vp->v_mount->mnt_flag & MNT_RDONLY) |
| 1184 | return EROFS; |
| 1185 | break; |
| 1186 | |
| 1187 | case VBLK: |
| 1188 | /* FALLTHROUGH */ |
| 1189 | case VCHR: |
| 1190 | /* FALLTHROUGH */ |
| 1191 | case VFIFO: |
| 1192 | /* Allow modifications of special files even if in the file |
| 1193 | * system is mounted read-only (we are not modifying the |
| 1194 | * files themselves, but the objects they represent). */ |
| 1195 | return 0; |
| 1196 | |
| 1197 | default: |
| 1198 | /* Anything else is unsupported. */ |
| 1199 | return EOPNOTSUPP; |
| 1200 | } |
| 1201 | |
| 1202 | /* Immutable or append-only files cannot be modified, either. */ |
| 1203 | if (node->tn_flags & (IMMUTABLE | APPEND)) |
| 1204 | return EPERM; |
| 1205 | |
| 1206 | error = tmpfs_truncate(vp, size); |
| 1207 | /* tmpfs_truncate will raise the NOTE_EXTEND and NOTE_ATTRIB kevents |
| 1208 | * for us, as will update tn_status; no need to do that here. */ |
| 1209 | |
| 1210 | KKASSERT(vn_islocked(vp)); |
| 1211 | |
| 1212 | return error; |
| 1213 | } |
| 1214 | |
| 1215 | /* --------------------------------------------------------------------- */ |
| 1216 | |
| 1217 | /* |
| 1218 | * Change access and modification times of the given vnode. |
| 1219 | * Caller should execute tmpfs_update on vp after a successful execution. |
| 1220 | * The vnode must be locked on entry and remain locked on exit. |
| 1221 | */ |
| 1222 | int |
| 1223 | tmpfs_chtimes(struct vnode *vp, struct timespec *atime, struct timespec *mtime, |
| 1224 | int vaflags, struct ucred *cred) |
| 1225 | { |
| 1226 | struct tmpfs_node *node; |
| 1227 | |
| 1228 | KKASSERT(vn_islocked(vp)); |
| 1229 | |
| 1230 | node = VP_TO_TMPFS_NODE(vp); |
| 1231 | |
| 1232 | /* Disallow this operation if the file system is mounted read-only. */ |
| 1233 | if (vp->v_mount->mnt_flag & MNT_RDONLY) |
| 1234 | return EROFS; |
| 1235 | |
| 1236 | /* Immutable or append-only files cannot be modified, either. */ |
| 1237 | if (node->tn_flags & (IMMUTABLE | APPEND)) |
| 1238 | return EPERM; |
| 1239 | |
| 1240 | TMPFS_NODE_LOCK(node); |
| 1241 | if (atime->tv_sec != VNOVAL && atime->tv_nsec != VNOVAL) |
| 1242 | node->tn_status |= TMPFS_NODE_ACCESSED; |
| 1243 | |
| 1244 | if (mtime->tv_sec != VNOVAL && mtime->tv_nsec != VNOVAL) |
| 1245 | node->tn_status |= TMPFS_NODE_MODIFIED; |
| 1246 | |
| 1247 | TMPFS_NODE_UNLOCK(node); |
| 1248 | |
| 1249 | tmpfs_itimes(vp, atime, mtime); |
| 1250 | |
| 1251 | KKASSERT(vn_islocked(vp)); |
| 1252 | |
| 1253 | return 0; |
| 1254 | } |
| 1255 | |
| 1256 | /* --------------------------------------------------------------------- */ |
| 1257 | /* Sync timestamps */ |
| 1258 | void |
| 1259 | tmpfs_itimes(struct vnode *vp, const struct timespec *acc, |
| 1260 | const struct timespec *mod) |
| 1261 | { |
| 1262 | struct tmpfs_node *node; |
| 1263 | struct timespec now; |
| 1264 | |
| 1265 | node = VP_TO_TMPFS_NODE(vp); |
| 1266 | |
| 1267 | if ((node->tn_status & (TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED | |
| 1268 | TMPFS_NODE_CHANGED)) == 0) |
| 1269 | return; |
| 1270 | |
| 1271 | vfs_timestamp(&now); |
| 1272 | |
| 1273 | TMPFS_NODE_LOCK(node); |
| 1274 | if (node->tn_status & TMPFS_NODE_ACCESSED) { |
| 1275 | if (acc == NULL) |
| 1276 | acc = &now; |
| 1277 | node->tn_atime = acc->tv_sec; |
| 1278 | node->tn_atimensec = acc->tv_nsec; |
| 1279 | } |
| 1280 | if (node->tn_status & TMPFS_NODE_MODIFIED) { |
| 1281 | if (mod == NULL) |
| 1282 | mod = &now; |
| 1283 | node->tn_mtime = mod->tv_sec; |
| 1284 | node->tn_mtimensec = mod->tv_nsec; |
| 1285 | } |
| 1286 | if (node->tn_status & TMPFS_NODE_CHANGED) { |
| 1287 | node->tn_ctime = now.tv_sec; |
| 1288 | node->tn_ctimensec = now.tv_nsec; |
| 1289 | } |
| 1290 | node->tn_status &= |
| 1291 | ~(TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED | TMPFS_NODE_CHANGED); |
| 1292 | TMPFS_NODE_UNLOCK(node); |
| 1293 | } |
| 1294 | |
| 1295 | /* --------------------------------------------------------------------- */ |
| 1296 | |
| 1297 | void |
| 1298 | tmpfs_update(struct vnode *vp) |
| 1299 | { |
| 1300 | |
| 1301 | tmpfs_itimes(vp, NULL, NULL); |
| 1302 | } |
| 1303 | |
| 1304 | /* --------------------------------------------------------------------- */ |
| 1305 | |
| 1306 | int |
| 1307 | tmpfs_truncate(struct vnode *vp, off_t length) |
| 1308 | { |
| 1309 | int error; |
| 1310 | struct tmpfs_node *node; |
| 1311 | |
| 1312 | node = VP_TO_TMPFS_NODE(vp); |
| 1313 | |
| 1314 | if (length < 0) { |
| 1315 | error = EINVAL; |
| 1316 | goto out; |
| 1317 | } |
| 1318 | |
| 1319 | if (node->tn_size == length) { |
| 1320 | error = 0; |
| 1321 | goto out; |
| 1322 | } |
| 1323 | |
| 1324 | if (length > VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize) |
| 1325 | return (EFBIG); |
| 1326 | |
| 1327 | |
| 1328 | error = tmpfs_reg_resize(vp, length, 1); |
| 1329 | |
| 1330 | if (error == 0) { |
| 1331 | TMPFS_NODE_LOCK(node); |
| 1332 | node->tn_status |= TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED; |
| 1333 | TMPFS_NODE_UNLOCK(node); |
| 1334 | } |
| 1335 | |
| 1336 | out: |
| 1337 | tmpfs_update(vp); |
| 1338 | |
| 1339 | return error; |
| 1340 | } |
| 1341 | |
| 1342 | /* --------------------------------------------------------------------- */ |
| 1343 | |
| 1344 | static ino_t |
| 1345 | tmpfs_fetch_ino(struct tmpfs_mount *tmp) |
| 1346 | { |
| 1347 | ino_t ret; |
| 1348 | |
| 1349 | ret = tmp->tm_ino++; |
| 1350 | |
| 1351 | return (ret); |
| 1352 | } |
| 1353 | |
| 1354 | static int |
| 1355 | tmpfs_dirtree_compare(struct tmpfs_dirent *a, struct tmpfs_dirent *b) |
| 1356 | { |
| 1357 | if (a->td_namelen > b->td_namelen) |
| 1358 | return 1; |
| 1359 | else if (a->td_namelen < b->td_namelen) |
| 1360 | return -1; |
| 1361 | else |
| 1362 | return strncmp(a->td_name, b->td_name, a->td_namelen); |
| 1363 | } |