tmpfs - Fix write-append/mmap-read race
[dragonfly.git] / sys / vfs / tmpfs / tmpfs_subr.c
CommitLineData
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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 */
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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>
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42#include <sys/stat.h>
43#include <sys/systm.h>
44#include <sys/vnode.h>
45#include <sys/vmmeter.h>
46
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47#include <vm/vm.h>
48#include <vm/vm_object.h>
49#include <vm/vm_page.h>
50#include <vm/vm_pager.h>
51#include <vm/vm_extern.h>
52
53#include <vfs/tmpfs/tmpfs.h>
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54#include <vfs/tmpfs/tmpfs_vnops.h>
55
f7db522f 56static ino_t tmpfs_fetch_ino(struct tmpfs_mount *);
f5f22af6 57
29ca4fd6
JH
58static int tmpfs_dirtree_compare(struct tmpfs_dirent *a,
59 struct tmpfs_dirent *b);
29ca4fd6
JH
60RB_GENERATE(tmpfs_dirtree, tmpfs_dirent, rb_node, tmpfs_dirtree_compare);
61
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MD
62static int tmpfs_dirtree_compare_cookie(struct tmpfs_dirent *a,
63 struct tmpfs_dirent *b);
64RB_GENERATE(tmpfs_dirtree_cookie, tmpfs_dirent,
65 rb_cookienode, tmpfs_dirtree_compare_cookie);
66
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MD
67
68/* --------------------------------------------------------------------- */
69
70/*
71 * Allocates a new node of type 'type' inside the 'tmp' mount point, with
72 * its owner set to 'uid', its group to 'gid' and its mode set to 'mode',
73 * using the credentials of the process 'p'.
74 *
75 * If the node type is set to 'VDIR', then the parent parameter must point
76 * to the parent directory of the node being created. It may only be NULL
77 * while allocating the root node.
78 *
79 * If the node type is set to 'VBLK' or 'VCHR', then the rdev parameter
80 * specifies the device the node represents.
81 *
82 * If the node type is set to 'VLNK', then the parameter target specifies
83 * the file name of the target file for the symbolic link that is being
84 * created.
85 *
86 * Note that new nodes are retrieved from the available list if it has
87 * items or, if it is empty, from the node pool as long as there is enough
88 * space to create them.
89 *
90 * Returns zero on success or an appropriate error code on failure.
91 */
92int
93tmpfs_alloc_node(struct tmpfs_mount *tmp, enum vtype type,
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94 uid_t uid, gid_t gid, mode_t mode,
95 char *target, int rmajor, int rminor,
96 struct tmpfs_node **node)
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97{
98 struct tmpfs_node *nnode;
99 struct timespec ts;
100 udev_t rdev;
101
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102 KKASSERT(IFF(type == VLNK, target != NULL));
103 KKASSERT(IFF(type == VBLK || type == VCHR, rmajor != VNOVAL));
104
52ce5c29 105 if (tmp->tm_nodes_inuse >= tmp->tm_nodes_max)
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106 return (ENOSPC);
107
881dac8b
VS
108 nnode = objcache_get(tmp->tm_node_pool, M_WAITOK | M_NULLOK);
109 if (nnode == NULL)
110 return (ENOSPC);
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111
112 /* Generic initialization. */
113 nnode->tn_type = type;
114 vfs_timestamp(&ts);
115 nnode->tn_ctime = nnode->tn_mtime = nnode->tn_atime
116 = ts.tv_sec;
117 nnode->tn_ctimensec = nnode->tn_mtimensec = nnode->tn_atimensec
118 = ts.tv_nsec;
119 nnode->tn_uid = uid;
120 nnode->tn_gid = gid;
121 nnode->tn_mode = mode;
f7db522f 122 nnode->tn_id = tmpfs_fetch_ino(tmp);
12a5de0e 123 nnode->tn_advlock.init_done = 0;
6e0c5aab 124 KKASSERT(nnode->tn_links == 0);
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125
126 /* Type-specific initialization. */
127 switch (nnode->tn_type) {
128 case VBLK:
129 case VCHR:
130 rdev = makeudev(rmajor, rminor);
131 if (rdev == NOUDEV) {
42f6f6b1 132 objcache_put(tmp->tm_node_pool, nnode);
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133 return(EINVAL);
134 }
135 nnode->tn_rdev = rdev;
136 break;
137
138 case VDIR:
29ca4fd6 139 RB_INIT(&nnode->tn_dir.tn_dirtree);
f5f22af6 140 RB_INIT(&nnode->tn_dir.tn_cookietree);
7a2de9a4 141 nnode->tn_size = 0;
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142 break;
143
144 case VFIFO:
145 /* FALLTHROUGH */
146 case VSOCK:
147 break;
148
149 case VLNK:
9fc94b5f 150 nnode->tn_size = strlen(target);
d00cd01c 151 nnode->tn_link = kmalloc(nnode->tn_size + 1, tmp->tm_name_zone,
42f6f6b1
VS
152 M_WAITOK | M_NULLOK);
153 if (nnode->tn_link == NULL) {
154 objcache_put(tmp->tm_node_pool, nnode);
155 return (ENOSPC);
156 }
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157 bcopy(target, nnode->tn_link, nnode->tn_size);
158 nnode->tn_link[nnode->tn_size] = '\0';
159 break;
160
161 case VREG:
162 nnode->tn_reg.tn_aobj =
5a648714 163 swap_pager_alloc(NULL, 0, VM_PROT_DEFAULT, 0);
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164 nnode->tn_reg.tn_aobj_pages = 0;
165 nnode->tn_size = 0;
166 break;
167
168 default:
169 panic("tmpfs_alloc_node: type %p %d", nnode, (int)nnode->tn_type);
170 }
171
172 TMPFS_NODE_LOCK(nnode);
7a2de9a4 173 TMPFS_LOCK(tmp);
0786baf1 174 LIST_INSERT_HEAD(&tmp->tm_nodes_used, nnode, tn_entries);
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175 tmp->tm_nodes_inuse++;
176 TMPFS_UNLOCK(tmp);
177 TMPFS_NODE_UNLOCK(nnode);
178
179 *node = nnode;
180 return 0;
181}
182
183/* --------------------------------------------------------------------- */
184
185/*
186 * Destroys the node pointed to by node from the file system 'tmp'.
187 * If the node does not belong to the given mount point, the results are
188 * unpredicted.
189 *
190 * If the node references a directory; no entries are allowed because
191 * their removal could need a recursive algorithm, something forbidden in
192 * kernel space. Furthermore, there is not need to provide such
193 * functionality (recursive removal) because the only primitives offered
194 * to the user are the removal of empty directories and the deletion of
195 * individual files.
196 *
197 * Note that nodes are not really deleted; in fact, when a node has been
198 * allocated, it cannot be deleted during the whole life of the file
199 * system. Instead, they are moved to the available list and remain there
200 * until reused.
c5552356
TK
201 *
202 * A caller must have TMPFS_NODE_LOCK(node) and this function unlocks it.
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203 */
204void
205tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node)
206{
29ffeb28 207 vm_pindex_t pages = 0;
7a2de9a4 208
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209#ifdef INVARIANTS
210 TMPFS_ASSERT_ELOCKED(node);
211 KKASSERT(node->tn_vnode == NULL);
212 KKASSERT((node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0);
213#endif
214
7a2de9a4 215 TMPFS_LOCK(tmp);
0786baf1 216 LIST_REMOVE(node, tn_entries);
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217 tmp->tm_nodes_inuse--;
218 TMPFS_UNLOCK(tmp);
c5552356 219 TMPFS_NODE_UNLOCK(node); /* Caller has this lock */
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220
221 switch (node->tn_type) {
222 case VNON:
223 /* Do not do anything. VNON is provided to let the
224 * allocation routine clean itself easily by avoiding
225 * duplicating code in it. */
226 /* FALLTHROUGH */
227 case VBLK:
228 /* FALLTHROUGH */
229 case VCHR:
230 /* FALLTHROUGH */
231 break;
232 case VDIR:
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233 /*
234 * The parent link can be NULL if this is the root
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235 * node or if it is a directory node that was rmdir'd.
236 *
237 * XXX what if node is a directory which still contains
238 * directory entries (e.g. due to a forced umount) ?
0786baf1 239 */
7a2de9a4 240 node->tn_size = 0;
6e0c5aab 241 KKASSERT(node->tn_dir.tn_parent == NULL);
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242
243 /*
244 * If the root node is being destroyed don't leave a
245 * dangling pointer in tmpfs_mount.
246 */
247 if (node == tmp->tm_root)
248 tmp->tm_root = NULL;
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249 break;
250 case VFIFO:
251 /* FALLTHROUGH */
252 case VSOCK:
253 break;
254
255 case VLNK:
d00cd01c 256 kfree(node->tn_link, tmp->tm_name_zone);
9fc94b5f 257 node->tn_link = NULL;
2706b587 258 node->tn_size = 0;
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259 break;
260
261 case VREG:
262 if (node->tn_reg.tn_aobj != NULL)
f96f2f39 263 vm_object_deallocate(node->tn_reg.tn_aobj);
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264 node->tn_reg.tn_aobj = NULL;
265 pages = node->tn_reg.tn_aobj_pages;
266 break;
267
268 default:
269 panic("tmpfs_free_node: type %p %d", node, (int)node->tn_type);
270 }
271
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MD
272 /*
273 * Clean up fields for the next allocation. The objcache only ctors
274 * new allocations.
275 */
276 tmpfs_node_ctor(node, NULL, 0);
7a2de9a4 277 objcache_put(tmp->tm_node_pool, node);
0786baf1 278 /* node is now invalid */
7a2de9a4 279
b37a7c00 280 atomic_add_long(&tmp->tm_pages_used, -(long)pages);
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MD
281}
282
283/* --------------------------------------------------------------------- */
284
285/*
286 * Allocates a new directory entry for the node node with a name of name.
287 * The new directory entry is returned in *de.
288 *
289 * The link count of node is increased by one to reflect the new object
290 * referencing it.
291 *
292 * Returns zero on success or an appropriate error code on failure.
293 */
294int
295tmpfs_alloc_dirent(struct tmpfs_mount *tmp, struct tmpfs_node *node,
aa1adbf0 296 const char *name, uint16_t len, struct tmpfs_dirent **de)
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297{
298 struct tmpfs_dirent *nde;
299
42f6f6b1 300 nde = objcache_get(tmp->tm_dirent_pool, M_WAITOK);
d00cd01c 301 nde->td_name = kmalloc(len + 1, tmp->tm_name_zone, M_WAITOK | M_NULLOK);
42f6f6b1
VS
302 if (nde->td_name == NULL) {
303 objcache_put(tmp->tm_dirent_pool, nde);
304 *de = NULL;
305 return (ENOSPC);
306 }
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307 nde->td_namelen = len;
308 bcopy(name, nde->td_name, len);
309 nde->td_name[len] = '\0';
310
311 nde->td_node = node;
312
313 TMPFS_NODE_LOCK(node);
ff837cd5 314 ++node->tn_links;
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315 TMPFS_NODE_UNLOCK(node);
316
317 *de = nde;
318
319 return 0;
320}
321
322/* --------------------------------------------------------------------- */
323
324/*
325 * Frees a directory entry. It is the caller's responsibility to destroy
326 * the node referenced by it if needed.
327 *
328 * The link count of node is decreased by one to reflect the removal of an
329 * object that referenced it. This only happens if 'node_exists' is true;
330 * otherwise the function will not access the node referred to by the
331 * directory entry, as it may already have been released from the outside.
332 */
333void
0786baf1 334tmpfs_free_dirent(struct tmpfs_mount *tmp, struct tmpfs_dirent *de)
7a2de9a4 335{
0786baf1 336 struct tmpfs_node *node;
7a2de9a4 337
0786baf1 338 node = de->td_node;
7a2de9a4 339
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MD
340 TMPFS_NODE_LOCK(node);
341 TMPFS_ASSERT_ELOCKED(node);
342 KKASSERT(node->tn_links > 0);
ff837cd5 343 node->tn_links--;
0786baf1 344 TMPFS_NODE_UNLOCK(node);
7a2de9a4 345
d00cd01c 346 kfree(de->td_name, tmp->tm_name_zone);
0786baf1 347 de->td_namelen = 0;
9fc94b5f 348 de->td_name = NULL;
0786baf1 349 de->td_node = NULL;
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350 objcache_put(tmp->tm_dirent_pool, de);
351}
352
353/* --------------------------------------------------------------------- */
354
355/*
356 * Allocates a new vnode for the node node or returns a new reference to
357 * an existing one if the node had already a vnode referencing it. The
358 * resulting locked vnode is returned in *vpp.
359 *
360 * Returns zero on success or an appropriate error code on failure.
361 */
362int
363tmpfs_alloc_vp(struct mount *mp, struct tmpfs_node *node, int lkflag,
2706b587 364 struct vnode **vpp)
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MD
365{
366 int error = 0;
367 struct vnode *vp;
368
369loop:
2706b587
MD
370 /*
371 * Interlocked extraction from node. This can race many things.
372 * We have to get a soft reference on the vnode while we hold
373 * the node locked, then acquire it properly and check for races.
374 */
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MD
375 TMPFS_NODE_LOCK(node);
376 if ((vp = node->tn_vnode) != NULL) {
377 KKASSERT((node->tn_vpstate & TMPFS_VNODE_DOOMED) == 0);
ee173d09 378 vhold(vp);
7a2de9a4 379 TMPFS_NODE_UNLOCK(node);
7a2de9a4 380
2706b587
MD
381 if (vget(vp, lkflag | LK_EXCLUSIVE) != 0) {
382 vdrop(vp);
383 goto loop;
384 }
385 if (node->tn_vnode != vp) {
7a2de9a4 386 vput(vp);
2706b587 387 vdrop(vp);
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MD
388 goto loop;
389 }
2706b587 390 vdrop(vp);
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391 goto out;
392 }
2706b587 393 /* vp is NULL */
7a2de9a4 394
0786baf1
MD
395 /*
396 * This should never happen.
397 */
398 if (node->tn_vpstate & TMPFS_VNODE_DOOMED) {
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MD
399 TMPFS_NODE_UNLOCK(node);
400 error = ENOENT;
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MD
401 goto out;
402 }
403
404 /*
2706b587
MD
405 * Interlock against other calls to tmpfs_alloc_vp() trying to
406 * allocate and assign a vp to node.
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MD
407 */
408 if (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) {
409 node->tn_vpstate |= TMPFS_VNODE_WANT;
2706b587
MD
410 error = tsleep(&node->tn_vpstate, PINTERLOCKED | PCATCH,
411 "tmpfs_alloc_vp", 0);
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MD
412 TMPFS_NODE_UNLOCK(node);
413 if (error)
414 return error;
7a2de9a4 415 goto loop;
2706b587
MD
416 }
417 node->tn_vpstate |= TMPFS_VNODE_ALLOCATING;
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MD
418 TMPFS_NODE_UNLOCK(node);
419
2706b587
MD
420 /*
421 * Allocate a new vnode (may block). The ALLOCATING flag should
422 * prevent a race against someone else assigning node->tn_vnode.
423 */
7a2de9a4
MD
424 error = getnewvnode(VT_TMPFS, mp, &vp, VLKTIMEOUT, LK_CANRECURSE);
425 if (error != 0)
426 goto unlock;
7a2de9a4 427
2706b587
MD
428 KKASSERT(node->tn_vnode == NULL);
429 KKASSERT(vp != NULL);
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MD
430 vp->v_data = node;
431 vp->v_type = node->tn_type;
432
433 /* Type-specific initialization. */
434 switch (node->tn_type) {
435 case VBLK:
436 /* FALLTHROUGH */
437 case VCHR:
438 /* FALLTHROUGH */
439 case VSOCK:
440 break;
441 case VREG:
3c54bb74 442 vinitvmio(vp, node->tn_size, TMPFS_BLKMASK, -1);
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MD
443 break;
444 case VLNK:
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MD
445 break;
446 case VFIFO:
447 vp->v_ops = &mp->mnt_vn_fifo_ops;
448 break;
449 case VDIR:
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450 break;
451
452 default:
453 panic("tmpfs_alloc_vp: type %p %d", node, (int)node->tn_type);
454 }
455
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456
457unlock:
458 TMPFS_NODE_LOCK(node);
459
460 KKASSERT(node->tn_vpstate & TMPFS_VNODE_ALLOCATING);
461 node->tn_vpstate &= ~TMPFS_VNODE_ALLOCATING;
462 node->tn_vnode = vp;
463
464 if (node->tn_vpstate & TMPFS_VNODE_WANT) {
465 node->tn_vpstate &= ~TMPFS_VNODE_WANT;
466 TMPFS_NODE_UNLOCK(node);
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MD
467 wakeup(&node->tn_vpstate);
468 } else {
7a2de9a4 469 TMPFS_NODE_UNLOCK(node);
2706b587 470 }
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471
472out:
473 *vpp = vp;
474
475 KKASSERT(IFF(error == 0, *vpp != NULL && vn_islocked(*vpp)));
476#ifdef INVARIANTS
477 TMPFS_NODE_LOCK(node);
478 KKASSERT(*vpp == node->tn_vnode);
479 TMPFS_NODE_UNLOCK(node);
480#endif
481
482 return error;
483}
484
485/* --------------------------------------------------------------------- */
486
487/*
488 * Destroys the association between the vnode vp and the node it
489 * references.
490 */
491void
492tmpfs_free_vp(struct vnode *vp)
493{
494 struct tmpfs_node *node;
495
496 node = VP_TO_TMPFS_NODE(vp);
497
498 TMPFS_NODE_LOCK(node);
499 KKASSERT(lockcount(TMPFS_NODE_MTX(node)) > 0);
500 node->tn_vnode = NULL;
7a2de9a4 501 vp->v_data = NULL;
d86d27a8 502 TMPFS_NODE_UNLOCK(node);
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MD
503}
504
505/* --------------------------------------------------------------------- */
506
507/*
508 * Allocates a new file of type 'type' and adds it to the parent directory
509 * 'dvp'; this addition is done using the component name given in 'cnp'.
510 * The ownership of the new file is automatically assigned based on the
511 * credentials of the caller (through 'cnp'), the group is set based on
512 * the parent directory and the mode is determined from the 'vap' argument.
513 * If successful, *vpp holds a vnode to the newly created file and zero
514 * is returned. Otherwise *vpp is NULL and the function returns an
515 * appropriate error code.
516 */
517int
518tmpfs_alloc_file(struct vnode *dvp, struct vnode **vpp, struct vattr *vap,
2706b587 519 struct namecache *ncp, struct ucred *cred, char *target)
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520{
521 int error;
522 struct tmpfs_dirent *de;
523 struct tmpfs_mount *tmp;
524 struct tmpfs_node *dnode;
525 struct tmpfs_node *node;
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MD
526
527 tmp = VFS_TO_TMPFS(dvp->v_mount);
528 dnode = VP_TO_TMPFS_DIR(dvp);
529 *vpp = NULL;
530
6e0c5aab
MD
531 /*
532 * If the directory was removed but a process was CD'd into it,
533 * we do not allow any more file/dir creation within it. Otherwise
534 * we will lose track of it.
535 */
536 KKASSERT(dnode->tn_type == VDIR);
537 if (dnode != tmp->tm_root && dnode->tn_dir.tn_parent == NULL)
538 return ENOENT;
7a2de9a4 539
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MD
540 /*
541 * Make sure the link count does not overflow.
542 */
543 if (vap->va_type == VDIR && dnode->tn_links >= LINK_MAX)
544 return EMLINK;
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MD
545
546 /* Allocate a node that represents the new file. */
547 error = tmpfs_alloc_node(tmp, vap->va_type, cred->cr_uid,
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548 dnode->tn_gid, vap->va_mode, target,
549 vap->va_rmajor, vap->va_rminor, &node);
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550 if (error != 0)
551 return error;
0786baf1 552 TMPFS_NODE_LOCK(node);
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553
554 /* Allocate a directory entry that points to the new file. */
0786baf1 555 error = tmpfs_alloc_dirent(tmp, node, ncp->nc_name, ncp->nc_nlen, &de);
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MD
556 if (error != 0) {
557 tmpfs_free_node(tmp, node);
0786baf1 558 /* eats node lock */
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559 return error;
560 }
561
562 /* Allocate a vnode for the new file. */
563 error = tmpfs_alloc_vp(dvp->v_mount, node, LK_EXCLUSIVE, vpp);
564 if (error != 0) {
0786baf1 565 tmpfs_free_dirent(tmp, de);
7a2de9a4 566 tmpfs_free_node(tmp, node);
0786baf1 567 /* eats node lock */
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568 return error;
569 }
570
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571 /*
572 * Now that all required items are allocated, we can proceed to
7a2de9a4 573 * insert the new node into the directory, an operation that
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574 * cannot fail.
575 */
22d3b394 576 tmpfs_dir_attach(dnode, de);
0786baf1 577 TMPFS_NODE_UNLOCK(node);
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578
579 return error;
580}
581
582/* --------------------------------------------------------------------- */
583
584/*
9855a822 585 * Attaches the directory entry de to the directory represented by dnode.
7a2de9a4
MD
586 * Note that this does not change the link count of the node pointed by
587 * the directory entry, as this is done by tmpfs_alloc_dirent.
588 */
589void
22d3b394 590tmpfs_dir_attach(struct tmpfs_node *dnode, struct tmpfs_dirent *de)
7a2de9a4 591{
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MD
592 struct tmpfs_node *node = de->td_node;
593
22d3b394 594 TMPFS_NODE_LOCK(dnode);
6e0c5aab
MD
595 if (node && node->tn_type == VDIR) {
596 TMPFS_NODE_LOCK(node);
ff837cd5 597 ++node->tn_links;
6e0c5aab
MD
598 node->tn_status |= TMPFS_NODE_CHANGED;
599 node->tn_dir.tn_parent = dnode;
ff837cd5 600 ++dnode->tn_links;
6e0c5aab
MD
601 TMPFS_NODE_UNLOCK(node);
602 }
29ca4fd6 603 RB_INSERT(tmpfs_dirtree, &dnode->tn_dir.tn_dirtree, de);
f5f22af6 604 RB_INSERT(tmpfs_dirtree_cookie, &dnode->tn_dir.tn_cookietree, de);
7a2de9a4 605 dnode->tn_size += sizeof(struct tmpfs_dirent);
22d3b394
MD
606 dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
607 TMPFS_NODE_MODIFIED;
7a2de9a4
MD
608 TMPFS_NODE_UNLOCK(dnode);
609}
610
611/* --------------------------------------------------------------------- */
612
613/*
9855a822 614 * Detaches the directory entry de from the directory represented by dnode.
7a2de9a4
MD
615 * Note that this does not change the link count of the node pointed by
616 * the directory entry, as this is done by tmpfs_free_dirent.
617 */
618void
22d3b394 619tmpfs_dir_detach(struct tmpfs_node *dnode, struct tmpfs_dirent *de)
7a2de9a4 620{
6e0c5aab
MD
621 struct tmpfs_node *node = de->td_node;
622
22d3b394 623 TMPFS_NODE_LOCK(dnode);
29ca4fd6 624 RB_REMOVE(tmpfs_dirtree, &dnode->tn_dir.tn_dirtree, de);
f5f22af6 625 RB_REMOVE(tmpfs_dirtree_cookie, &dnode->tn_dir.tn_cookietree, de);
7a2de9a4 626 dnode->tn_size -= sizeof(struct tmpfs_dirent);
22d3b394
MD
627 dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED |
628 TMPFS_NODE_MODIFIED;
7a2de9a4 629 TMPFS_NODE_UNLOCK(dnode);
6e0c5aab
MD
630
631 /*
632 * Clean out the tn_parent pointer immediately when removing a
633 * directory.
634 *
635 * Removal of the parent linkage also cleans out the extra tn_links
636 * count we had on both node and dnode.
637 *
638 * node can be NULL (typ during a forced umount), in which case
639 * the mount code is dealing with the linkages from a linked list
640 * scan.
641 */
642 if (node && node->tn_type == VDIR && node->tn_dir.tn_parent) {
643 TMPFS_NODE_LOCK(dnode);
644 TMPFS_NODE_LOCK(node);
645 KKASSERT(node->tn_dir.tn_parent == dnode);
ff837cd5
MD
646 dnode->tn_links--;
647 node->tn_links--;
6e0c5aab
MD
648 node->tn_dir.tn_parent = NULL;
649 TMPFS_NODE_UNLOCK(node);
650 TMPFS_NODE_UNLOCK(dnode);
651 }
7a2de9a4
MD
652}
653
654/* --------------------------------------------------------------------- */
655
656/*
657 * Looks for a directory entry in the directory represented by node.
658 * 'ncp' describes the name of the entry to look for. Note that the .
659 * and .. components are not allowed as they do not physically exist
660 * within directories.
661 *
662 * Returns a pointer to the entry when found, otherwise NULL.
ff837cd5
MD
663 *
664 * Caller must hold the node locked (shared ok)
7a2de9a4
MD
665 */
666struct tmpfs_dirent *
667tmpfs_dir_lookup(struct tmpfs_node *node, struct tmpfs_node *f,
6e0c5aab 668 struct namecache *ncp)
7a2de9a4 669{
7a2de9a4
MD
670 struct tmpfs_dirent *de;
671 int len = ncp->nc_nlen;
29ca4fd6
JH
672 struct tmpfs_dirent wanted;
673
674 wanted.td_namelen = len;
675 wanted.td_name = ncp->nc_name;
7a2de9a4
MD
676
677 TMPFS_VALIDATE_DIR(node);
678
29ca4fd6
JH
679 de = RB_FIND(tmpfs_dirtree, &node->tn_dir.tn_dirtree, &wanted);
680
681 KKASSERT(f == NULL || f == de->td_node);
7a2de9a4 682
9fc94b5f 683 return de;
7a2de9a4
MD
684}
685
686/* --------------------------------------------------------------------- */
687
688/*
689 * Helper function for tmpfs_readdir. Creates a '.' entry for the given
690 * directory and returns it in the uio space. The function returns 0
691 * on success, -1 if there was not enough space in the uio structure to
692 * hold the directory entry or an appropriate error code if another
693 * error happens.
694 */
695int
696tmpfs_dir_getdotdent(struct tmpfs_node *node, struct uio *uio)
697{
698 int error;
699 struct dirent dent;
700 int dirsize;
701
702 TMPFS_VALIDATE_DIR(node);
703 KKASSERT(uio->uio_offset == TMPFS_DIRCOOKIE_DOT);
704
705 dent.d_ino = node->tn_id;
706 dent.d_type = DT_DIR;
707 dent.d_namlen = 1;
708 dent.d_name[0] = '.';
709 dent.d_name[1] = '\0';
710 dirsize = _DIRENT_DIRSIZ(&dent);
711
712 if (dirsize > uio->uio_resid)
713 error = -1;
714 else {
715 error = uiomove((caddr_t)&dent, dirsize, uio);
716 if (error == 0)
717 uio->uio_offset = TMPFS_DIRCOOKIE_DOTDOT;
718 }
7a2de9a4
MD
719 return error;
720}
721
722/* --------------------------------------------------------------------- */
723
724/*
725 * Helper function for tmpfs_readdir. Creates a '..' entry for the given
726 * directory and returns it in the uio space. The function returns 0
727 * on success, -1 if there was not enough space in the uio structure to
728 * hold the directory entry or an appropriate error code if another
729 * error happens.
730 */
731int
22d3b394
MD
732tmpfs_dir_getdotdotdent(struct tmpfs_mount *tmp, struct tmpfs_node *node,
733 struct uio *uio)
7a2de9a4
MD
734{
735 int error;
736 struct dirent dent;
737 int dirsize;
738
739 TMPFS_VALIDATE_DIR(node);
740 KKASSERT(uio->uio_offset == TMPFS_DIRCOOKIE_DOTDOT);
741
22d3b394 742 if (node->tn_dir.tn_parent) {
b08327b7
MD
743 TMPFS_NODE_LOCK(node);
744 if (node->tn_dir.tn_parent)
745 dent.d_ino = node->tn_dir.tn_parent->tn_id;
746 else
747 dent.d_ino = tmp->tm_root->tn_id;
748 TMPFS_NODE_UNLOCK(node);
22d3b394
MD
749 } else {
750 dent.d_ino = tmp->tm_root->tn_id;
7a2de9a4
MD
751 }
752
7a2de9a4
MD
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
f5f22af6
MD
767 de = RB_MIN(tmpfs_dirtree_cookie,
768 &node->tn_dir.tn_cookietree);
7a2de9a4
MD
769 if (de == NULL)
770 uio->uio_offset = TMPFS_DIRCOOKIE_EOF;
771 else
772 uio->uio_offset = tmpfs_dircookie(de);
773 }
774 }
7a2de9a4
MD
775 return error;
776}
777
778/* --------------------------------------------------------------------- */
779
780/*
781 * Lookup a directory entry by its associated cookie.
f5f22af6
MD
782 *
783 * Must be called with the directory node locked (shared ok)
7a2de9a4 784 */
f5f22af6
MD
785struct lubycookie_info {
786 off_t cookie;
7a2de9a4 787 struct tmpfs_dirent *de;
f5f22af6 788};
7a2de9a4 789
f5f22af6
MD
790static int
791lubycookie_cmp(struct tmpfs_dirent *de, void *arg)
792{
793 struct lubycookie_info *info = arg;
794 off_t cookie = tmpfs_dircookie(de);
795
796 if (cookie < info->cookie)
797 return(-1);
798 if (cookie > info->cookie)
799 return(1);
800 return(0);
801}
7a2de9a4 802
f5f22af6
MD
803static int
804lubycookie_callback(struct tmpfs_dirent *de, void *arg)
805{
806 struct lubycookie_info *info = arg;
807
808 if (tmpfs_dircookie(de) == info->cookie) {
809 info->de = de;
810 return(-1);
7a2de9a4 811 }
f5f22af6
MD
812 return(0);
813}
7a2de9a4 814
f5f22af6
MD
815struct tmpfs_dirent *
816tmpfs_dir_lookupbycookie(struct tmpfs_node *node, off_t cookie)
817{
818 struct lubycookie_info info;
819
820 info.cookie = cookie;
821 info.de = NULL;
822 RB_SCAN(tmpfs_dirtree_cookie, &node->tn_dir.tn_cookietree,
823 lubycookie_cmp, lubycookie_callback, &info);
824 return (info.de);
7a2de9a4
MD
825}
826
827/* --------------------------------------------------------------------- */
828
829/*
830 * Helper function for tmpfs_readdir. Returns as much directory entries
831 * as can fit in the uio space. The read starts at uio->uio_offset.
832 * The function returns 0 on success, -1 if there was not enough space
833 * in the uio structure to hold the directory entry or an appropriate
834 * error code if another error happens.
833d1222
MD
835 *
836 * Caller must hold the node locked (shared ok)
7a2de9a4
MD
837 */
838int
839tmpfs_dir_getdents(struct tmpfs_node *node, struct uio *uio, off_t *cntp)
840{
841 int error;
842 off_t startcookie;
843 struct tmpfs_dirent *de;
844
845 TMPFS_VALIDATE_DIR(node);
846
833d1222
MD
847 /*
848 * Locate the first directory entry we have to return. We have cached
7a2de9a4 849 * the last readdir in the node, so use those values if appropriate.
833d1222
MD
850 * Otherwise do a linear scan to find the requested entry.
851 */
7a2de9a4
MD
852 startcookie = uio->uio_offset;
853 KKASSERT(startcookie != TMPFS_DIRCOOKIE_DOT);
854 KKASSERT(startcookie != TMPFS_DIRCOOKIE_DOTDOT);
833d1222
MD
855
856 if (startcookie == TMPFS_DIRCOOKIE_EOF)
7a2de9a4 857 return 0;
833d1222
MD
858
859 de = tmpfs_dir_lookupbycookie(node, startcookie);
860 if (de == NULL)
7a2de9a4 861 return EINVAL;
7a2de9a4 862
f5f22af6
MD
863 /*
864 * Read as much entries as possible; i.e., until we reach the end of
865 * the directory or we exhaust uio space.
866 */
7a2de9a4
MD
867 do {
868 struct dirent d;
869 int reclen;
870
871 /* Create a dirent structure representing the current
872 * tmpfs_node and fill it. */
873 d.d_ino = de->td_node->tn_id;
874 switch (de->td_node->tn_type) {
875 case VBLK:
876 d.d_type = DT_BLK;
877 break;
878
879 case VCHR:
880 d.d_type = DT_CHR;
881 break;
882
883 case VDIR:
884 d.d_type = DT_DIR;
885 break;
886
887 case VFIFO:
888 d.d_type = DT_FIFO;
889 break;
890
891 case VLNK:
892 d.d_type = DT_LNK;
893 break;
894
895 case VREG:
896 d.d_type = DT_REG;
897 break;
898
899 case VSOCK:
900 d.d_type = DT_SOCK;
901 break;
902
903 default:
904 panic("tmpfs_dir_getdents: type %p %d",
905 de->td_node, (int)de->td_node->tn_type);
906 }
907 d.d_namlen = de->td_namelen;
908 KKASSERT(de->td_namelen < sizeof(d.d_name));
909 bcopy(de->td_name, d.d_name, d.d_namlen);
910 d.d_name[d.d_namlen] = '\0';
911 reclen = _DIRENT_RECLEN(d.d_namlen);
912
913 /* Stop reading if the directory entry we are treating is
914 * bigger than the amount of data that can be returned. */
915 if (reclen > uio->uio_resid) {
916 error = -1;
917 break;
918 }
919
920 /* Copy the new dirent structure into the output buffer and
921 * advance pointers. */
922 error = uiomove((caddr_t)&d, reclen, uio);
923
924 (*cntp)++;
f5f22af6
MD
925 de = RB_NEXT(tmpfs_dirtree_cookie,
926 node->tn_dir.tn_cookietree, de);
7a2de9a4
MD
927 } while (error == 0 && uio->uio_resid > 0 && de != NULL);
928
929 /* Update the offset and cache. */
930 if (de == NULL) {
931 uio->uio_offset = TMPFS_DIRCOOKIE_EOF;
7a2de9a4 932 } else {
f5f22af6 933 uio->uio_offset = tmpfs_dircookie(de);
7a2de9a4 934 }
7a2de9a4
MD
935
936 return error;
937}
938
939/* --------------------------------------------------------------------- */
940
941/*
942 * Resizes the aobj associated to the regular file pointed to by vp to
943 * the size newsize. 'vp' must point to a vnode that represents a regular
944 * file. 'newsize' must be positive.
945 *
946 * pass trivial as 1 when buf content will be overwritten, otherwise set 0
947 * to be zero filled.
948 *
949 * Returns zero on success or an appropriate error code on failure.
b37a7c00
MD
950 *
951 * Caller must hold the node exclusively locked.
7a2de9a4
MD
952 */
953int
954tmpfs_reg_resize(struct vnode *vp, off_t newsize, int trivial)
955{
956 int error;
29ffeb28 957 vm_pindex_t newpages, oldpages;
7a2de9a4
MD
958 struct tmpfs_mount *tmp;
959 struct tmpfs_node *node;
960 off_t oldsize;
7a2de9a4
MD
961
962#ifdef INVARIANTS
963 KKASSERT(vp->v_type == VREG);
964 KKASSERT(newsize >= 0);
965#endif
966
967 node = VP_TO_TMPFS_NODE(vp);
968 tmp = VFS_TO_TMPFS(vp->v_mount);
969
ff837cd5
MD
970 /*
971 * Convert the old and new sizes to the number of pages needed to
7a2de9a4
MD
972 * store them. It may happen that we do not need to do anything
973 * because the last allocated page can accommodate the change on
ff837cd5
MD
974 * its own.
975 */
7a2de9a4 976 oldsize = node->tn_size;
29ffeb28 977 oldpages = round_page64(oldsize) / PAGE_SIZE;
7a2de9a4 978 KKASSERT(oldpages == node->tn_reg.tn_aobj_pages);
29ffeb28 979 newpages = round_page64(newsize) / PAGE_SIZE;
7a2de9a4
MD
980
981 if (newpages > oldpages &&
29ffeb28 982 tmp->tm_pages_used + newpages - oldpages > tmp->tm_pages_max) {
7a2de9a4
MD
983 error = ENOSPC;
984 goto out;
985 }
ff837cd5
MD
986 node->tn_reg.tn_aobj_pages = newpages;
987 node->tn_size = newsize;
7a2de9a4 988
b37a7c00 989 atomic_add_long(&tmp->tm_pages_used, (newpages - oldpages));
7a2de9a4 990
9fc94b5f
MD
991 /*
992 * When adjusting the vnode filesize and its VM object we must
993 * also adjust our backing VM object (aobj). The blocksize
994 * used must match the block sized we use for the buffer cache.
22d3b394
MD
995 *
996 * The backing VM object contains no VM pages, only swap
997 * assignments.
9fc94b5f
MD
998 */
999 if (newsize < oldsize) {
1000 vm_pindex_t osize;
22d3b394 1001 vm_pindex_t nsize;
9fc94b5f
MD
1002 vm_object_t aobj;
1003
3c54bb74 1004 error = nvtruncbuf(vp, newsize, TMPFS_BLKSIZE, -1, 0);
9fc94b5f
MD
1005 aobj = node->tn_reg.tn_aobj;
1006 if (aobj) {
1007 osize = aobj->size;
22d3b394
MD
1008 nsize = vp->v_object->size;
1009 if (nsize < osize) {
9fc94b5f 1010 aobj->size = osize;
22d3b394
MD
1011 swap_pager_freespace(aobj, nsize,
1012 osize - nsize);
9fc94b5f
MD
1013 }
1014 }
1015 } else {
1016 vm_object_t aobj;
1017
3c54bb74
MD
1018 error = nvextendbuf(vp, oldsize, newsize,
1019 TMPFS_BLKSIZE, TMPFS_BLKSIZE,
7a2de9a4 1020 -1, -1, trivial);
9fc94b5f
MD
1021 aobj = node->tn_reg.tn_aobj;
1022 if (aobj)
1023 aobj->size = vp->v_object->size;
1024 }
7a2de9a4
MD
1025
1026out:
1027 return error;
1028}
1029
1030/* --------------------------------------------------------------------- */
1031
1032/*
1033 * Change flags of the given vnode.
1034 * Caller should execute tmpfs_update on vp after a successful execution.
1035 * The vnode must be locked on entry and remain locked on exit.
1036 */
1037int
80ae59d7 1038tmpfs_chflags(struct vnode *vp, int vaflags, struct ucred *cred)
7a2de9a4
MD
1039{
1040 int error;
1041 struct tmpfs_node *node;
80ae59d7 1042 int flags;
7a2de9a4
MD
1043
1044 KKASSERT(vn_islocked(vp));
1045
1046 node = VP_TO_TMPFS_NODE(vp);
80ae59d7 1047 flags = node->tn_flags;
7a2de9a4
MD
1048
1049 /* Disallow this operation if the file system is mounted read-only. */
1050 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1051 return EROFS;
80ae59d7 1052 error = vop_helper_setattr_flags(&flags, vaflags, node->tn_uid, cred);
7a2de9a4 1053
5339dfe4 1054 /* Actually change the flags on the node itself */
80ae59d7
MD
1055 if (error == 0) {
1056 TMPFS_NODE_LOCK(node);
5339dfe4 1057 node->tn_flags = flags;
80ae59d7
MD
1058 node->tn_status |= TMPFS_NODE_CHANGED;
1059 TMPFS_NODE_UNLOCK(node);
7a2de9a4 1060 }
7a2de9a4
MD
1061
1062 KKASSERT(vn_islocked(vp));
1063
80ae59d7 1064 return error;
7a2de9a4
MD
1065}
1066
1067/* --------------------------------------------------------------------- */
1068
1069/*
1070 * Change access mode on the given vnode.
1071 * Caller should execute tmpfs_update on vp after a successful execution.
1072 * The vnode must be locked on entry and remain locked on exit.
1073 */
1074int
80ae59d7 1075tmpfs_chmod(struct vnode *vp, mode_t vamode, struct ucred *cred)
7a2de9a4 1076{
7a2de9a4 1077 struct tmpfs_node *node;
80ae59d7
MD
1078 mode_t cur_mode;
1079 int error;
7a2de9a4
MD
1080
1081 KKASSERT(vn_islocked(vp));
1082
1083 node = VP_TO_TMPFS_NODE(vp);
1084
1085 /* Disallow this operation if the file system is mounted read-only. */
1086 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1087 return EROFS;
1088
1089 /* Immutable or append-only files cannot be modified, either. */
1090 if (node->tn_flags & (IMMUTABLE | APPEND))
1091 return EPERM;
1092
80ae59d7
MD
1093 cur_mode = node->tn_mode;
1094 error = vop_helper_chmod(vp, vamode, cred, node->tn_uid, node->tn_gid,
1095 &cur_mode);
7a2de9a4 1096
80ae59d7
MD
1097 if (error == 0 &&
1098 (node->tn_mode & ALLPERMS) != (cur_mode & ALLPERMS)) {
1099 TMPFS_NODE_LOCK(node);
1100 node->tn_mode &= ~ALLPERMS;
1101 node->tn_mode |= cur_mode & ALLPERMS;
7a2de9a4 1102
80ae59d7
MD
1103 node->tn_status |= TMPFS_NODE_CHANGED;
1104 TMPFS_NODE_UNLOCK(node);
7a2de9a4
MD
1105 }
1106
7a2de9a4
MD
1107 KKASSERT(vn_islocked(vp));
1108
1109 return 0;
1110}
1111
1112/* --------------------------------------------------------------------- */
1113
1114/*
1115 * Change ownership of the given vnode. At least one of uid or gid must
1116 * be different than VNOVAL. If one is set to that value, the attribute
1117 * is unchanged.
1118 * Caller should execute tmpfs_update on vp after a successful execution.
1119 * The vnode must be locked on entry and remain locked on exit.
1120 */
1121int
1122tmpfs_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred)
1123{
bd48f29c
MD
1124 mode_t cur_mode;
1125 uid_t cur_uid;
1126 gid_t cur_gid;
7a2de9a4 1127 struct tmpfs_node *node;
bd48f29c 1128 int error;
7a2de9a4
MD
1129
1130 KKASSERT(vn_islocked(vp));
7a2de9a4
MD
1131 node = VP_TO_TMPFS_NODE(vp);
1132
7a2de9a4
MD
1133 /* Disallow this operation if the file system is mounted read-only. */
1134 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1135 return EROFS;
1136
1137 /* Immutable or append-only files cannot be modified, either. */
1138 if (node->tn_flags & (IMMUTABLE | APPEND))
1139 return EPERM;
1140
bd48f29c
MD
1141 cur_uid = node->tn_uid;
1142 cur_gid = node->tn_gid;
1143 cur_mode = node->tn_mode;
1144 error = vop_helper_chown(vp, uid, gid, cred,
1145 &cur_uid, &cur_gid, &cur_mode);
1146
1147 if (error == 0) {
1148 TMPFS_NODE_LOCK(node);
1149 if (cur_uid != node->tn_uid ||
1150 cur_gid != node->tn_gid ||
1151 cur_mode != node->tn_mode) {
3b9337bb
YT
1152 node->tn_uid = cur_uid;
1153 node->tn_gid = cur_gid;
bd48f29c
MD
1154 node->tn_mode = cur_mode;
1155 node->tn_status |= TMPFS_NODE_CHANGED;
7a2de9a4 1156 }
bd48f29c 1157 TMPFS_NODE_UNLOCK(node);
7a2de9a4 1158 }
7a2de9a4 1159
bd48f29c 1160 return error;
7a2de9a4
MD
1161}
1162
1163/* --------------------------------------------------------------------- */
1164
1165/*
1166 * Change size of the given vnode.
1167 * Caller should execute tmpfs_update on vp after a successful execution.
1168 * The vnode must be locked on entry and remain locked on exit.
1169 */
1170int
1171tmpfs_chsize(struct vnode *vp, u_quad_t size, struct ucred *cred)
1172{
1173 int error;
1174 struct tmpfs_node *node;
1175
1176 KKASSERT(vn_islocked(vp));
1177
1178 node = VP_TO_TMPFS_NODE(vp);
1179
1180 /* Decide whether this is a valid operation based on the file type. */
1181 error = 0;
1182 switch (vp->v_type) {
1183 case VDIR:
1184 return EISDIR;
1185
1186 case VREG:
1187 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1188 return EROFS;
1189 break;
1190
1191 case VBLK:
1192 /* FALLTHROUGH */
1193 case VCHR:
1194 /* FALLTHROUGH */
1195 case VFIFO:
1196 /* Allow modifications of special files even if in the file
1197 * system is mounted read-only (we are not modifying the
1198 * files themselves, but the objects they represent). */
1199 return 0;
1200
1201 default:
1202 /* Anything else is unsupported. */
1203 return EOPNOTSUPP;
1204 }
1205
1206 /* Immutable or append-only files cannot be modified, either. */
1207 if (node->tn_flags & (IMMUTABLE | APPEND))
1208 return EPERM;
1209
1210 error = tmpfs_truncate(vp, size);
1211 /* tmpfs_truncate will raise the NOTE_EXTEND and NOTE_ATTRIB kevents
1212 * for us, as will update tn_status; no need to do that here. */
1213
1214 KKASSERT(vn_islocked(vp));
1215
1216 return error;
1217}
1218
1219/* --------------------------------------------------------------------- */
1220
1221/*
1222 * Change access and modification times of the given vnode.
1223 * Caller should execute tmpfs_update on vp after a successful execution.
1224 * The vnode must be locked on entry and remain locked on exit.
1225 */
1226int
1227tmpfs_chtimes(struct vnode *vp, struct timespec *atime, struct timespec *mtime,
aa1adbf0 1228 int vaflags, struct ucred *cred)
7a2de9a4 1229{
7a2de9a4 1230 struct tmpfs_node *node;
7a2de9a4
MD
1231
1232 KKASSERT(vn_islocked(vp));
1233
1234 node = VP_TO_TMPFS_NODE(vp);
1235
1236 /* Disallow this operation if the file system is mounted read-only. */
1237 if (vp->v_mount->mnt_flag & MNT_RDONLY)
1238 return EROFS;
1239
1240 /* Immutable or append-only files cannot be modified, either. */
1241 if (node->tn_flags & (IMMUTABLE | APPEND))
1242 return EPERM;
1243
7a2de9a4
MD
1244 TMPFS_NODE_LOCK(node);
1245 if (atime->tv_sec != VNOVAL && atime->tv_nsec != VNOVAL)
1246 node->tn_status |= TMPFS_NODE_ACCESSED;
1247
1248 if (mtime->tv_sec != VNOVAL && mtime->tv_nsec != VNOVAL)
1249 node->tn_status |= TMPFS_NODE_MODIFIED;
1250
1251 TMPFS_NODE_UNLOCK(node);
1252
1253 tmpfs_itimes(vp, atime, mtime);
1254
1255 KKASSERT(vn_islocked(vp));
1256
1257 return 0;
1258}
1259
1260/* --------------------------------------------------------------------- */
1261/* Sync timestamps */
1262void
1263tmpfs_itimes(struct vnode *vp, const struct timespec *acc,
aa1adbf0 1264 const struct timespec *mod)
7a2de9a4
MD
1265{
1266 struct tmpfs_node *node;
1267 struct timespec now;
1268
1269 node = VP_TO_TMPFS_NODE(vp);
1270
1271 if ((node->tn_status & (TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED |
1272 TMPFS_NODE_CHANGED)) == 0)
1273 return;
1274
1275 vfs_timestamp(&now);
1276
1277 TMPFS_NODE_LOCK(node);
1278 if (node->tn_status & TMPFS_NODE_ACCESSED) {
1279 if (acc == NULL)
1280 acc = &now;
1281 node->tn_atime = acc->tv_sec;
1282 node->tn_atimensec = acc->tv_nsec;
1283 }
1284 if (node->tn_status & TMPFS_NODE_MODIFIED) {
1285 if (mod == NULL)
1286 mod = &now;
1287 node->tn_mtime = mod->tv_sec;
1288 node->tn_mtimensec = mod->tv_nsec;
1289 }
1290 if (node->tn_status & TMPFS_NODE_CHANGED) {
1291 node->tn_ctime = now.tv_sec;
1292 node->tn_ctimensec = now.tv_nsec;
1293 }
1294 node->tn_status &=
1295 ~(TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED | TMPFS_NODE_CHANGED);
1296 TMPFS_NODE_UNLOCK(node);
1297}
1298
1299/* --------------------------------------------------------------------- */
1300
1301void
1302tmpfs_update(struct vnode *vp)
1303{
7a2de9a4
MD
1304 tmpfs_itimes(vp, NULL, NULL);
1305}
1306
1307/* --------------------------------------------------------------------- */
1308
b37a7c00
MD
1309/*
1310 * Caller must hold an exclusive node lock.
1311 */
7a2de9a4
MD
1312int
1313tmpfs_truncate(struct vnode *vp, off_t length)
1314{
1315 int error;
1316 struct tmpfs_node *node;
1317
1318 node = VP_TO_TMPFS_NODE(vp);
1319
1320 if (length < 0) {
1321 error = EINVAL;
1322 goto out;
1323 }
1324
1325 if (node->tn_size == length) {
1326 error = 0;
1327 goto out;
1328 }
1329
1330 if (length > VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize)
1331 return (EFBIG);
1332
1333
1334 error = tmpfs_reg_resize(vp, length, 1);
1335
b37a7c00 1336 if (error == 0)
7a2de9a4 1337 node->tn_status |= TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED;
7a2de9a4
MD
1338
1339out:
1340 tmpfs_update(vp);
1341
1342 return error;
1343}
1344
1345/* --------------------------------------------------------------------- */
1346
1347static ino_t
f7db522f 1348tmpfs_fetch_ino(struct tmpfs_mount *tmp)
7a2de9a4 1349{
f7db522f 1350 ino_t ret;
7a2de9a4 1351
23db3379 1352 TMPFS_LOCK(tmp);
f7db522f 1353 ret = tmp->tm_ino++;
23db3379 1354 TMPFS_UNLOCK(tmp);
7a2de9a4 1355
f7db522f 1356 return (ret);
7a2de9a4 1357}
29ca4fd6
JH
1358
1359static int
1360tmpfs_dirtree_compare(struct tmpfs_dirent *a, struct tmpfs_dirent *b)
1361{
1362 if (a->td_namelen > b->td_namelen)
1363 return 1;
1364 else if (a->td_namelen < b->td_namelen)
1365 return -1;
1366 else
1367 return strncmp(a->td_name, b->td_name, a->td_namelen);
1368}
f5f22af6
MD
1369
1370static int
1371tmpfs_dirtree_compare_cookie(struct tmpfs_dirent *a, struct tmpfs_dirent *b)
1372{
1373 if (a < b)
1374 return(-1);
1375 if (a > b)
1376 return(1);
1377 return 0;
1378}