1 /* $NetBSD: tmpfs_vnops.c,v 1.39 2007/07/23 15:41:01 jmmv Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-2-Clause-NetBSD
5 *
6 * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc.
7 * All rights reserved.
8 *
9 * This code is derived from software contributed to The NetBSD Foundation
10 * by Julio M. Merino Vidal, developed as part of Google's Summer of Code
11 * 2005 program.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
26 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32 * POSSIBILITY OF SUCH DAMAGE.
33 */
34
35 /*
36 * tmpfs vnode interface.
37 */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/dirent.h>
44 #include <sys/fcntl.h>
45 #include <sys/file.h>
46 #include <sys/limits.h>
47 #include <sys/lockf.h>
48 #include <sys/lock.h>
49 #include <sys/mount.h>
50 #include <sys/namei.h>
51 #include <sys/priv.h>
52 #include <sys/proc.h>
53 #include <sys/rwlock.h>
54 #include <sys/sched.h>
55 #include <sys/stat.h>
56 #include <sys/sysctl.h>
57 #include <sys/unistd.h>
58 #include <sys/vnode.h>
59 #include <sys/smr.h>
60 #include <security/audit/audit.h>
61 #include <security/mac/mac_framework.h>
62
63 #include <vm/vm.h>
64 #include <vm/vm_param.h>
65 #include <vm/vm_object.h>
66
67 #include <fs/tmpfs/tmpfs_vnops.h>
68 #include <fs/tmpfs/tmpfs.h>
69
70 SYSCTL_DECL(_vfs_tmpfs);
71 VFS_SMR_DECLARE;
72
73 static volatile int tmpfs_rename_restarts;
74 SYSCTL_INT(_vfs_tmpfs, OID_AUTO, rename_restarts, CTLFLAG_RD,
75 __DEVOLATILE(int *, &tmpfs_rename_restarts), 0,
76 "Times rename had to restart due to lock contention");
77
78 static int
79 tmpfs_vn_get_ino_alloc(struct mount *mp, void *arg, int lkflags,
80 struct vnode **rvp)
81 {
82
83 return (tmpfs_alloc_vp(mp, arg, lkflags, rvp));
84 }
85
86 static int
87 tmpfs_lookup1(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
88 {
89 struct tmpfs_dirent *de;
90 struct tmpfs_node *dnode, *pnode;
91 struct tmpfs_mount *tm;
92 int error;
93
94 /* Caller assumes responsibility for ensuring access (VEXEC). */
95 dnode = VP_TO_TMPFS_DIR(dvp);
96 *vpp = NULLVP;
97
98 /* We cannot be requesting the parent directory of the root node. */
99 MPASS(IMPLIES(dnode->tn_type == VDIR &&
100 dnode->tn_dir.tn_parent == dnode,
101 !(cnp->cn_flags & ISDOTDOT)));
102
103 TMPFS_ASSERT_LOCKED(dnode);
104 if (dnode->tn_dir.tn_parent == NULL) {
105 error = ENOENT;
106 goto out;
107 }
108 if (cnp->cn_flags & ISDOTDOT) {
109 tm = VFS_TO_TMPFS(dvp->v_mount);
110 pnode = dnode->tn_dir.tn_parent;
111 tmpfs_ref_node(pnode);
112 error = vn_vget_ino_gen(dvp, tmpfs_vn_get_ino_alloc,
113 pnode, cnp->cn_lkflags, vpp);
114 tmpfs_free_node(tm, pnode);
115 if (error != 0)
116 goto out;
117 } else if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') {
118 VREF(dvp);
119 *vpp = dvp;
120 error = 0;
121 } else {
122 de = tmpfs_dir_lookup(dnode, NULL, cnp);
123 if (de != NULL && de->td_node == NULL)
124 cnp->cn_flags |= ISWHITEOUT;
125 if (de == NULL || de->td_node == NULL) {
126 /*
127 * The entry was not found in the directory.
128 * This is OK if we are creating or renaming an
129 * entry and are working on the last component of
130 * the path name.
131 */
132 if ((cnp->cn_flags & ISLASTCN) &&
133 (cnp->cn_nameiop == CREATE || \
134 cnp->cn_nameiop == RENAME ||
135 (cnp->cn_nameiop == DELETE &&
136 cnp->cn_flags & DOWHITEOUT &&
137 cnp->cn_flags & ISWHITEOUT))) {
138 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred,
139 cnp->cn_thread);
140 if (error != 0)
141 goto out;
142
143 /*
144 * Keep the component name in the buffer for
145 * future uses.
146 */
147 cnp->cn_flags |= SAVENAME;
148
149 error = EJUSTRETURN;
150 } else
151 error = ENOENT;
152 } else {
153 struct tmpfs_node *tnode;
154
155 /*
156 * The entry was found, so get its associated
157 * tmpfs_node.
158 */
159 tnode = de->td_node;
160
161 /*
162 * If we are not at the last path component and
163 * found a non-directory or non-link entry (which
164 * may itself be pointing to a directory), raise
165 * an error.
166 */
167 if ((tnode->tn_type != VDIR &&
168 tnode->tn_type != VLNK) &&
169 !(cnp->cn_flags & ISLASTCN)) {
170 error = ENOTDIR;
171 goto out;
172 }
173
174 /*
175 * If we are deleting or renaming the entry, keep
176 * track of its tmpfs_dirent so that it can be
177 * easily deleted later.
178 */
179 if ((cnp->cn_flags & ISLASTCN) &&
180 (cnp->cn_nameiop == DELETE ||
181 cnp->cn_nameiop == RENAME)) {
182 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred,
183 cnp->cn_thread);
184 if (error != 0)
185 goto out;
186
187 /* Allocate a new vnode on the matching entry. */
188 error = tmpfs_alloc_vp(dvp->v_mount, tnode,
189 cnp->cn_lkflags, vpp);
190 if (error != 0)
191 goto out;
192
193 if ((dnode->tn_mode & S_ISTXT) &&
194 VOP_ACCESS(dvp, VADMIN, cnp->cn_cred,
195 cnp->cn_thread) && VOP_ACCESS(*vpp, VADMIN,
196 cnp->cn_cred, cnp->cn_thread)) {
197 error = EPERM;
198 vput(*vpp);
199 *vpp = NULL;
200 goto out;
201 }
202 cnp->cn_flags |= SAVENAME;
203 } else {
204 error = tmpfs_alloc_vp(dvp->v_mount, tnode,
205 cnp->cn_lkflags, vpp);
206 if (error != 0)
207 goto out;
208 }
209 }
210 }
211
212 /*
213 * Store the result of this lookup in the cache. Avoid this if the
214 * request was for creation, as it does not improve timings on
215 * emprical tests.
216 */
217 if ((cnp->cn_flags & MAKEENTRY) != 0 && tmpfs_use_nc(dvp))
218 cache_enter(dvp, *vpp, cnp);
219
220 out:
221 /*
222 * If there were no errors, *vpp cannot be null and it must be
223 * locked.
224 */
225 MPASS(IFF(error == 0, *vpp != NULLVP && VOP_ISLOCKED(*vpp)));
226
227 return (error);
228 }
229
230 static int
231 tmpfs_cached_lookup(struct vop_cachedlookup_args *v)
232 {
233
234 return (tmpfs_lookup1(v->a_dvp, v->a_vpp, v->a_cnp));
235 }
236
237 static int
238 tmpfs_lookup(struct vop_lookup_args *v)
239 {
240 struct vnode *dvp = v->a_dvp;
241 struct vnode **vpp = v->a_vpp;
242 struct componentname *cnp = v->a_cnp;
243 int error;
244
245 /* Check accessibility of requested node as a first step. */
246 error = vn_dir_check_exec(dvp, cnp);
247 if (error != 0)
248 return (error);
249
250 return (tmpfs_lookup1(dvp, vpp, cnp));
251 }
252
253 static int
254 tmpfs_create(struct vop_create_args *v)
255 {
256 struct vnode *dvp = v->a_dvp;
257 struct vnode **vpp = v->a_vpp;
258 struct componentname *cnp = v->a_cnp;
259 struct vattr *vap = v->a_vap;
260 int error;
261
262 MPASS(vap->va_type == VREG || vap->va_type == VSOCK);
263
264 error = tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
265 if (error == 0 && (cnp->cn_flags & MAKEENTRY) != 0 && tmpfs_use_nc(dvp))
266 cache_enter(dvp, *vpp, cnp);
267 return (error);
268 }
269
270 static int
271 tmpfs_mknod(struct vop_mknod_args *v)
272 {
273 struct vnode *dvp = v->a_dvp;
274 struct vnode **vpp = v->a_vpp;
275 struct componentname *cnp = v->a_cnp;
276 struct vattr *vap = v->a_vap;
277
278 if (vap->va_type != VBLK && vap->va_type != VCHR &&
279 vap->va_type != VFIFO)
280 return EINVAL;
281
282 return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
283 }
284
285 struct fileops tmpfs_fnops;
286
287 static int
288 tmpfs_open(struct vop_open_args *v)
289 {
290 struct vnode *vp;
291 struct tmpfs_node *node;
292 struct file *fp;
293 int error, mode;
294
295 vp = v->a_vp;
296 mode = v->a_mode;
297 node = VP_TO_TMPFS_NODE(vp);
298
299 /*
300 * The file is still active but all its names have been removed
301 * (e.g. by a "rmdir $(pwd)"). It cannot be opened any more as
302 * it is about to die.
303 */
304 if (node->tn_links < 1)
305 return (ENOENT);
306
307 /* If the file is marked append-only, deny write requests. */
308 if (node->tn_flags & APPEND && (mode & (FWRITE | O_APPEND)) == FWRITE)
309 error = EPERM;
310 else {
311 error = 0;
312 /* For regular files, the call below is nop. */
313 KASSERT(vp->v_type != VREG || (node->tn_reg.tn_aobj->flags &
314 OBJ_DEAD) == 0, ("dead object"));
315 vnode_create_vobject(vp, node->tn_size, v->a_td);
316 }
317
318 fp = v->a_fp;
319 MPASS(fp == NULL || fp->f_data == NULL);
320 if (error == 0 && fp != NULL && vp->v_type == VREG) {
321 tmpfs_ref_node(node);
322 finit_vnode(fp, mode, node, &tmpfs_fnops);
323 }
324
325 return (error);
326 }
327
328 static int
329 tmpfs_close(struct vop_close_args *v)
330 {
331 struct vnode *vp = v->a_vp;
332
333 /* Update node times. */
334 tmpfs_update(vp);
335
336 return (0);
337 }
338
339 int
340 tmpfs_fo_close(struct file *fp, struct thread *td)
341 {
342 struct tmpfs_node *node;
343
344 node = fp->f_data;
345 if (node != NULL) {
346 MPASS(node->tn_type == VREG);
347 tmpfs_free_node(node->tn_reg.tn_tmp, node);
348 }
349 return (vnops.fo_close(fp, td));
350 }
351
352 /*
353 * VOP_FPLOOKUP_VEXEC routines are subject to special circumstances, see
354 * the comment above cache_fplookup for details.
355 */
356 int
357 tmpfs_fplookup_vexec(struct vop_fplookup_vexec_args *v)
358 {
359 struct vnode *vp;
360 struct tmpfs_node *node;
361 struct ucred *cred;
362 mode_t all_x, mode;
363
364 vp = v->a_vp;
365 node = VP_TO_TMPFS_NODE_SMR(vp);
366 if (__predict_false(node == NULL))
367 return (EAGAIN);
368
369 all_x = S_IXUSR | S_IXGRP | S_IXOTH;
370 mode = atomic_load_short(&node->tn_mode);
371 if (__predict_true((mode & all_x) == all_x))
372 return (0);
373
374 cred = v->a_cred;
375 return (vaccess_vexec_smr(mode, node->tn_uid, node->tn_gid, cred));
376 }
377
378 int
379 tmpfs_access(struct vop_access_args *v)
380 {
381 struct vnode *vp = v->a_vp;
382 accmode_t accmode = v->a_accmode;
383 struct ucred *cred = v->a_cred;
384 mode_t all_x = S_IXUSR | S_IXGRP | S_IXOTH;
385 int error;
386 struct tmpfs_node *node;
387
388 MPASS(VOP_ISLOCKED(vp));
389
390 node = VP_TO_TMPFS_NODE(vp);
391
392 /*
393 * Common case path lookup.
394 */
395 if (__predict_true(accmode == VEXEC && (node->tn_mode & all_x) == all_x))
396 return (0);
397
398 switch (vp->v_type) {
399 case VDIR:
400 /* FALLTHROUGH */
401 case VLNK:
402 /* FALLTHROUGH */
403 case VREG:
404 if (accmode & VWRITE && vp->v_mount->mnt_flag & MNT_RDONLY) {
405 error = EROFS;
406 goto out;
407 }
408 break;
409
410 case VBLK:
411 /* FALLTHROUGH */
412 case VCHR:
413 /* FALLTHROUGH */
414 case VSOCK:
415 /* FALLTHROUGH */
416 case VFIFO:
417 break;
418
419 default:
420 error = EINVAL;
421 goto out;
422 }
423
424 if (accmode & VWRITE && node->tn_flags & IMMUTABLE) {
425 error = EPERM;
426 goto out;
427 }
428
429 error = vaccess(vp->v_type, node->tn_mode, node->tn_uid, node->tn_gid,
430 accmode, cred);
431
432 out:
433 MPASS(VOP_ISLOCKED(vp));
434
435 return (error);
436 }
437
438 int
439 tmpfs_stat(struct vop_stat_args *v)
440 {
441 struct vnode *vp = v->a_vp;
442 struct stat *sb = v->a_sb;
443 vm_object_t obj;
444 struct tmpfs_node *node;
445 int error;
446
447 node = VP_TO_TMPFS_NODE(vp);
448
449 tmpfs_update_getattr(vp);
450
451 error = vop_stat_helper_pre(v);
452 if (__predict_false(error))
453 return (error);
454
455 sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0];
456 sb->st_ino = node->tn_id;
457 sb->st_mode = node->tn_mode | VTTOIF(vp->v_type);
458 sb->st_nlink = node->tn_links;
459 sb->st_uid = node->tn_uid;
460 sb->st_gid = node->tn_gid;
461 sb->st_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ?
462 node->tn_rdev : NODEV;
463 sb->st_size = node->tn_size;
464 sb->st_atim.tv_sec = node->tn_atime.tv_sec;
465 sb->st_atim.tv_nsec = node->tn_atime.tv_nsec;
466 sb->st_mtim.tv_sec = node->tn_mtime.tv_sec;
467 sb->st_mtim.tv_nsec = node->tn_mtime.tv_nsec;
468 sb->st_ctim.tv_sec = node->tn_ctime.tv_sec;
469 sb->st_ctim.tv_nsec = node->tn_ctime.tv_nsec;
470 sb->st_birthtim.tv_sec = node->tn_birthtime.tv_sec;
471 sb->st_birthtim.tv_nsec = node->tn_birthtime.tv_nsec;
472 sb->st_blksize = PAGE_SIZE;
473 sb->st_flags = node->tn_flags;
474 sb->st_gen = node->tn_gen;
475 if (vp->v_type == VREG) {
476 obj = node->tn_reg.tn_aobj;
477 sb->st_blocks = (u_quad_t)obj->resident_page_count * PAGE_SIZE;
478 } else
479 sb->st_blocks = node->tn_size;
480 sb->st_blocks /= S_BLKSIZE;
481 return (vop_stat_helper_post(v, error));
482 }
483
484 int
485 tmpfs_getattr(struct vop_getattr_args *v)
486 {
487 struct vnode *vp = v->a_vp;
488 struct vattr *vap = v->a_vap;
489 vm_object_t obj;
490 struct tmpfs_node *node;
491
492 node = VP_TO_TMPFS_NODE(vp);
493
494 tmpfs_update_getattr(vp);
495
496 vap->va_type = vp->v_type;
497 vap->va_mode = node->tn_mode;
498 vap->va_nlink = node->tn_links;
499 vap->va_uid = node->tn_uid;
500 vap->va_gid = node->tn_gid;
501 vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
502 vap->va_fileid = node->tn_id;
503 vap->va_size = node->tn_size;
504 vap->va_blocksize = PAGE_SIZE;
505 vap->va_atime = node->tn_atime;
506 vap->va_mtime = node->tn_mtime;
507 vap->va_ctime = node->tn_ctime;
508 vap->va_birthtime = node->tn_birthtime;
509 vap->va_gen = node->tn_gen;
510 vap->va_flags = node->tn_flags;
511 vap->va_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ?
512 node->tn_rdev : NODEV;
513 if (vp->v_type == VREG) {
514 obj = node->tn_reg.tn_aobj;
515 vap->va_bytes = (u_quad_t)obj->resident_page_count * PAGE_SIZE;
516 } else
517 vap->va_bytes = node->tn_size;
518 vap->va_filerev = 0;
519
520 return 0;
521 }
522
523 int
524 tmpfs_setattr(struct vop_setattr_args *v)
525 {
526 struct vnode *vp = v->a_vp;
527 struct vattr *vap = v->a_vap;
528 struct ucred *cred = v->a_cred;
529 struct thread *td = curthread;
530
531 int error;
532
533 MPASS(VOP_ISLOCKED(vp));
534 ASSERT_VOP_IN_SEQC(vp);
535
536 error = 0;
537
538 /* Abort if any unsettable attribute is given. */
539 if (vap->va_type != VNON ||
540 vap->va_nlink != VNOVAL ||
541 vap->va_fsid != VNOVAL ||
542 vap->va_fileid != VNOVAL ||
543 vap->va_blocksize != VNOVAL ||
544 vap->va_gen != VNOVAL ||
545 vap->va_rdev != VNOVAL ||
546 vap->va_bytes != VNOVAL)
547 error = EINVAL;
548
549 if (error == 0 && (vap->va_flags != VNOVAL))
550 error = tmpfs_chflags(vp, vap->va_flags, cred, td);
551
552 if (error == 0 && (vap->va_size != VNOVAL))
553 error = tmpfs_chsize(vp, vap->va_size, cred, td);
554
555 if (error == 0 && (vap->va_uid != VNOVAL || vap->va_gid != VNOVAL))
556 error = tmpfs_chown(vp, vap->va_uid, vap->va_gid, cred, td);
557
558 if (error == 0 && (vap->va_mode != (mode_t)VNOVAL))
559 error = tmpfs_chmod(vp, vap->va_mode, cred, td);
560
561 if (error == 0 && ((vap->va_atime.tv_sec != VNOVAL &&
562 vap->va_atime.tv_nsec != VNOVAL) ||
563 (vap->va_mtime.tv_sec != VNOVAL &&
564 vap->va_mtime.tv_nsec != VNOVAL) ||
565 (vap->va_birthtime.tv_sec != VNOVAL &&
566 vap->va_birthtime.tv_nsec != VNOVAL)))
567 error = tmpfs_chtimes(vp, vap, cred, td);
568
569 /*
570 * Update the node times. We give preference to the error codes
571 * generated by this function rather than the ones that may arise
572 * from tmpfs_update.
573 */
574 tmpfs_update(vp);
575
576 MPASS(VOP_ISLOCKED(vp));
577
578 return error;
579 }
580
581 static int
582 tmpfs_read(struct vop_read_args *v)
583 {
584 struct vnode *vp;
585 struct uio *uio;
586 struct tmpfs_node *node;
587
588 vp = v->a_vp;
589 if (vp->v_type != VREG)
590 return (EISDIR);
591 uio = v->a_uio;
592 if (uio->uio_offset < 0)
593 return (EINVAL);
594 node = VP_TO_TMPFS_NODE(vp);
595 tmpfs_set_accessed(VFS_TO_TMPFS(vp->v_mount), node);
596 return (uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio));
597 }
598
599 static int
600 tmpfs_read_pgcache(struct vop_read_pgcache_args *v)
601 {
602 struct vnode *vp;
603 struct tmpfs_node *node;
604 vm_object_t object;
605 off_t size;
606 int error;
607
608 vp = v->a_vp;
609 VNPASS((vn_irflag_read(vp) & VIRF_PGREAD) != 0, vp);
610
611 if (v->a_uio->uio_offset < 0)
612 return (EINVAL);
613
614 error = EJUSTRETURN;
615 vfs_smr_enter();
616
617 node = VP_TO_TMPFS_NODE_SMR(vp);
618 if (node == NULL)
619 goto out_smr;
620 MPASS(node->tn_type == VREG);
621 MPASS(node->tn_refcount >= 1);
622 object = node->tn_reg.tn_aobj;
623 if (object == NULL)
624 goto out_smr;
625
626 MPASS((object->flags & (OBJ_ANON | OBJ_DEAD | OBJ_TMPFS_NODE)) ==
627 OBJ_TMPFS_NODE);
628 if (!VN_IS_DOOMED(vp)) {
629 /* size cannot become shorter due to rangelock. */
630 size = node->tn_size;
631 tmpfs_set_accessed(node->tn_reg.tn_tmp, node);
632 vfs_smr_exit();
633 error = uiomove_object(object, size, v->a_uio);
634 return (error);
635 }
636 out_smr:
637 vfs_smr_exit();
638 return (error);
639 }
640
641 static int
642 tmpfs_write(struct vop_write_args *v)
643 {
644 struct vnode *vp;
645 struct uio *uio;
646 struct tmpfs_node *node;
647 off_t oldsize;
648 int error, ioflag;
649 mode_t newmode;
650
651 vp = v->a_vp;
652 uio = v->a_uio;
653 ioflag = v->a_ioflag;
654 error = 0;
655 node = VP_TO_TMPFS_NODE(vp);
656 oldsize = node->tn_size;
657
658 if (uio->uio_offset < 0 || vp->v_type != VREG)
659 return (EINVAL);
660 if (uio->uio_resid == 0)
661 return (0);
662 if (ioflag & IO_APPEND)
663 uio->uio_offset = node->tn_size;
664 if (uio->uio_offset + uio->uio_resid >
665 VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize)
666 return (EFBIG);
667 if (vn_rlimit_fsize(vp, uio, uio->uio_td))
668 return (EFBIG);
669 if (uio->uio_offset + uio->uio_resid > node->tn_size) {
670 error = tmpfs_reg_resize(vp, uio->uio_offset + uio->uio_resid,
671 FALSE);
672 if (error != 0)
673 goto out;
674 }
675
676 error = uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio);
677 node->tn_status |= TMPFS_NODE_MODIFIED | TMPFS_NODE_CHANGED;
678 node->tn_accessed = true;
679 if (node->tn_mode & (S_ISUID | S_ISGID)) {
680 if (priv_check_cred(v->a_cred, PRIV_VFS_RETAINSUGID)) {
681 newmode = node->tn_mode & ~(S_ISUID | S_ISGID);
682 vn_seqc_write_begin(vp);
683 atomic_store_short(&node->tn_mode, newmode);
684 vn_seqc_write_end(vp);
685 }
686 }
687 if (error != 0)
688 (void)tmpfs_reg_resize(vp, oldsize, TRUE);
689
690 out:
691 MPASS(IMPLIES(error == 0, uio->uio_resid == 0));
692 MPASS(IMPLIES(error != 0, oldsize == node->tn_size));
693
694 return (error);
695 }
696
697 static int
698 tmpfs_fsync(struct vop_fsync_args *v)
699 {
700 struct vnode *vp = v->a_vp;
701
702 MPASS(VOP_ISLOCKED(vp));
703
704 tmpfs_check_mtime(vp);
705 tmpfs_update(vp);
706
707 return 0;
708 }
709
710 static int
711 tmpfs_remove(struct vop_remove_args *v)
712 {
713 struct vnode *dvp = v->a_dvp;
714 struct vnode *vp = v->a_vp;
715
716 int error;
717 struct tmpfs_dirent *de;
718 struct tmpfs_mount *tmp;
719 struct tmpfs_node *dnode;
720 struct tmpfs_node *node;
721
722 MPASS(VOP_ISLOCKED(dvp));
723 MPASS(VOP_ISLOCKED(vp));
724
725 if (vp->v_type == VDIR) {
726 error = EISDIR;
727 goto out;
728 }
729
730 dnode = VP_TO_TMPFS_DIR(dvp);
731 node = VP_TO_TMPFS_NODE(vp);
732 tmp = VFS_TO_TMPFS(vp->v_mount);
733 de = tmpfs_dir_lookup(dnode, node, v->a_cnp);
734 MPASS(de != NULL);
735
736 /* Files marked as immutable or append-only cannot be deleted. */
737 if ((node->tn_flags & (IMMUTABLE | APPEND | NOUNLINK)) ||
738 (dnode->tn_flags & APPEND)) {
739 error = EPERM;
740 goto out;
741 }
742
743 /* Remove the entry from the directory; as it is a file, we do not
744 * have to change the number of hard links of the directory. */
745 tmpfs_dir_detach(dvp, de);
746 if (v->a_cnp->cn_flags & DOWHITEOUT)
747 tmpfs_dir_whiteout_add(dvp, v->a_cnp);
748
749 /* Free the directory entry we just deleted. Note that the node
750 * referred by it will not be removed until the vnode is really
751 * reclaimed. */
752 tmpfs_free_dirent(tmp, de);
753
754 node->tn_status |= TMPFS_NODE_CHANGED;
755 node->tn_accessed = true;
756 error = 0;
757
758 out:
759 return (error);
760 }
761
762 static int
763 tmpfs_link(struct vop_link_args *v)
764 {
765 struct vnode *dvp = v->a_tdvp;
766 struct vnode *vp = v->a_vp;
767 struct componentname *cnp = v->a_cnp;
768
769 int error;
770 struct tmpfs_dirent *de;
771 struct tmpfs_node *node;
772
773 MPASS(VOP_ISLOCKED(dvp));
774 MPASS(cnp->cn_flags & HASBUF);
775 MPASS(dvp != vp); /* XXX When can this be false? */
776 node = VP_TO_TMPFS_NODE(vp);
777
778 /* Ensure that we do not overflow the maximum number of links imposed
779 * by the system. */
780 MPASS(node->tn_links <= TMPFS_LINK_MAX);
781 if (node->tn_links == TMPFS_LINK_MAX) {
782 error = EMLINK;
783 goto out;
784 }
785
786 /* We cannot create links of files marked immutable or append-only. */
787 if (node->tn_flags & (IMMUTABLE | APPEND)) {
788 error = EPERM;
789 goto out;
790 }
791
792 /* Allocate a new directory entry to represent the node. */
793 error = tmpfs_alloc_dirent(VFS_TO_TMPFS(vp->v_mount), node,
794 cnp->cn_nameptr, cnp->cn_namelen, &de);
795 if (error != 0)
796 goto out;
797
798 /* Insert the new directory entry into the appropriate directory. */
799 if (cnp->cn_flags & ISWHITEOUT)
800 tmpfs_dir_whiteout_remove(dvp, cnp);
801 tmpfs_dir_attach(dvp, de);
802
803 /* vp link count has changed, so update node times. */
804 node->tn_status |= TMPFS_NODE_CHANGED;
805 tmpfs_update(vp);
806
807 error = 0;
808
809 out:
810 return error;
811 }
812
813 /*
814 * We acquire all but fdvp locks using non-blocking acquisitions. If we
815 * fail to acquire any lock in the path we will drop all held locks,
816 * acquire the new lock in a blocking fashion, and then release it and
817 * restart the rename. This acquire/release step ensures that we do not
818 * spin on a lock waiting for release. On error release all vnode locks
819 * and decrement references the way tmpfs_rename() would do.
820 */
821 static int
822 tmpfs_rename_relock(struct vnode *fdvp, struct vnode **fvpp,
823 struct vnode *tdvp, struct vnode **tvpp,
824 struct componentname *fcnp, struct componentname *tcnp)
825 {
826 struct vnode *nvp;
827 struct mount *mp;
828 struct tmpfs_dirent *de;
829 int error, restarts = 0;
830
831 VOP_UNLOCK(tdvp);
832 if (*tvpp != NULL && *tvpp != tdvp)
833 VOP_UNLOCK(*tvpp);
834 mp = fdvp->v_mount;
835
836 relock:
837 restarts += 1;
838 error = vn_lock(fdvp, LK_EXCLUSIVE);
839 if (error)
840 goto releout;
841 if (vn_lock(tdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
842 VOP_UNLOCK(fdvp);
843 error = vn_lock(tdvp, LK_EXCLUSIVE);
844 if (error)
845 goto releout;
846 VOP_UNLOCK(tdvp);
847 goto relock;
848 }
849 /*
850 * Re-resolve fvp to be certain it still exists and fetch the
851 * correct vnode.
852 */
853 de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(fdvp), NULL, fcnp);
854 if (de == NULL) {
855 VOP_UNLOCK(fdvp);
856 VOP_UNLOCK(tdvp);
857 if ((fcnp->cn_flags & ISDOTDOT) != 0 ||
858 (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.'))
859 error = EINVAL;
860 else
861 error = ENOENT;
862 goto releout;
863 }
864 error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE | LK_NOWAIT, &nvp);
865 if (error != 0) {
866 VOP_UNLOCK(fdvp);
867 VOP_UNLOCK(tdvp);
868 if (error != EBUSY)
869 goto releout;
870 error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, &nvp);
871 if (error != 0)
872 goto releout;
873 VOP_UNLOCK(nvp);
874 /*
875 * Concurrent rename race.
876 */
877 if (nvp == tdvp) {
878 vrele(nvp);
879 error = EINVAL;
880 goto releout;
881 }
882 vrele(*fvpp);
883 *fvpp = nvp;
884 goto relock;
885 }
886 vrele(*fvpp);
887 *fvpp = nvp;
888 VOP_UNLOCK(*fvpp);
889 /*
890 * Re-resolve tvp and acquire the vnode lock if present.
891 */
892 de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(tdvp), NULL, tcnp);
893 /*
894 * If tvp disappeared we just carry on.
895 */
896 if (de == NULL && *tvpp != NULL) {
897 vrele(*tvpp);
898 *tvpp = NULL;
899 }
900 /*
901 * Get the tvp ino if the lookup succeeded. We may have to restart
902 * if the non-blocking acquire fails.
903 */
904 if (de != NULL) {
905 nvp = NULL;
906 error = tmpfs_alloc_vp(mp, de->td_node,
907 LK_EXCLUSIVE | LK_NOWAIT, &nvp);
908 if (*tvpp != NULL)
909 vrele(*tvpp);
910 *tvpp = nvp;
911 if (error != 0) {
912 VOP_UNLOCK(fdvp);
913 VOP_UNLOCK(tdvp);
914 if (error != EBUSY)
915 goto releout;
916 error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE,
917 &nvp);
918 if (error != 0)
919 goto releout;
920 VOP_UNLOCK(nvp);
921 /*
922 * fdvp contains fvp, thus tvp (=fdvp) is not empty.
923 */
924 if (nvp == fdvp) {
925 error = ENOTEMPTY;
926 goto releout;
927 }
928 goto relock;
929 }
930 }
931 tmpfs_rename_restarts += restarts;
932
933 return (0);
934
935 releout:
936 vrele(fdvp);
937 vrele(*fvpp);
938 vrele(tdvp);
939 if (*tvpp != NULL)
940 vrele(*tvpp);
941 tmpfs_rename_restarts += restarts;
942
943 return (error);
944 }
945
946 static int
947 tmpfs_rename(struct vop_rename_args *v)
948 {
949 struct vnode *fdvp = v->a_fdvp;
950 struct vnode *fvp = v->a_fvp;
951 struct componentname *fcnp = v->a_fcnp;
952 struct vnode *tdvp = v->a_tdvp;
953 struct vnode *tvp = v->a_tvp;
954 struct componentname *tcnp = v->a_tcnp;
955 char *newname;
956 struct tmpfs_dirent *de;
957 struct tmpfs_mount *tmp;
958 struct tmpfs_node *fdnode;
959 struct tmpfs_node *fnode;
960 struct tmpfs_node *tnode;
961 struct tmpfs_node *tdnode;
962 int error;
963 bool want_seqc_end;
964
965 MPASS(VOP_ISLOCKED(tdvp));
966 MPASS(IMPLIES(tvp != NULL, VOP_ISLOCKED(tvp)));
967 MPASS(fcnp->cn_flags & HASBUF);
968 MPASS(tcnp->cn_flags & HASBUF);
969
970 want_seqc_end = false;
971
972 /*
973 * Disallow cross-device renames.
974 * XXX Why isn't this done by the caller?
975 */
976 if (fvp->v_mount != tdvp->v_mount ||
977 (tvp != NULL && fvp->v_mount != tvp->v_mount)) {
978 error = EXDEV;
979 goto out;
980 }
981
982 /* If source and target are the same file, there is nothing to do. */
983 if (fvp == tvp) {
984 error = 0;
985 goto out;
986 }
987
988 /*
989 * If we need to move the directory between entries, lock the
990 * source so that we can safely operate on it.
991 */
992 if (fdvp != tdvp && fdvp != tvp) {
993 if (vn_lock(fdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) {
994 error = tmpfs_rename_relock(fdvp, &fvp, tdvp, &tvp,
995 fcnp, tcnp);
996 if (error != 0)
997 return (error);
998 ASSERT_VOP_ELOCKED(fdvp,
999 "tmpfs_rename: fdvp not locked");
1000 ASSERT_VOP_ELOCKED(tdvp,
1001 "tmpfs_rename: tdvp not locked");
1002 if (tvp != NULL)
1003 ASSERT_VOP_ELOCKED(tvp,
1004 "tmpfs_rename: tvp not locked");
1005 if (fvp == tvp) {
1006 error = 0;
1007 goto out_locked;
1008 }
1009 }
1010 }
1011
1012 if (tvp != NULL)
1013 vn_seqc_write_begin(tvp);
1014 vn_seqc_write_begin(tdvp);
1015 vn_seqc_write_begin(fvp);
1016 vn_seqc_write_begin(fdvp);
1017 want_seqc_end = true;
1018
1019 tmp = VFS_TO_TMPFS(tdvp->v_mount);
1020 tdnode = VP_TO_TMPFS_DIR(tdvp);
1021 tnode = (tvp == NULL) ? NULL : VP_TO_TMPFS_NODE(tvp);
1022 fdnode = VP_TO_TMPFS_DIR(fdvp);
1023 fnode = VP_TO_TMPFS_NODE(fvp);
1024 de = tmpfs_dir_lookup(fdnode, fnode, fcnp);
1025
1026 /*
1027 * Entry can disappear before we lock fdvp,
1028 * also avoid manipulating '.' and '..' entries.
1029 */
1030 if (de == NULL) {
1031 if ((fcnp->cn_flags & ISDOTDOT) != 0 ||
1032 (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.'))
1033 error = EINVAL;
1034 else
1035 error = ENOENT;
1036 goto out_locked;
1037 }
1038 MPASS(de->td_node == fnode);
1039
1040 /*
1041 * If re-naming a directory to another preexisting directory
1042 * ensure that the target directory is empty so that its
1043 * removal causes no side effects.
1044 * Kern_rename guarantees the destination to be a directory
1045 * if the source is one.
1046 */
1047 if (tvp != NULL) {
1048 MPASS(tnode != NULL);
1049
1050 if ((tnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) ||
1051 (tdnode->tn_flags & (APPEND | IMMUTABLE))) {
1052 error = EPERM;
1053 goto out_locked;
1054 }
1055
1056 if (fnode->tn_type == VDIR && tnode->tn_type == VDIR) {
1057 if (tnode->tn_size > 0) {
1058 error = ENOTEMPTY;
1059 goto out_locked;
1060 }
1061 } else if (fnode->tn_type == VDIR && tnode->tn_type != VDIR) {
1062 error = ENOTDIR;
1063 goto out_locked;
1064 } else if (fnode->tn_type != VDIR && tnode->tn_type == VDIR) {
1065 error = EISDIR;
1066 goto out_locked;
1067 } else {
1068 MPASS(fnode->tn_type != VDIR &&
1069 tnode->tn_type != VDIR);
1070 }
1071 }
1072
1073 if ((fnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))
1074 || (fdnode->tn_flags & (APPEND | IMMUTABLE))) {
1075 error = EPERM;
1076 goto out_locked;
1077 }
1078
1079 /*
1080 * Ensure that we have enough memory to hold the new name, if it
1081 * has to be changed.
1082 */
1083 if (fcnp->cn_namelen != tcnp->cn_namelen ||
1084 bcmp(fcnp->cn_nameptr, tcnp->cn_nameptr, fcnp->cn_namelen) != 0) {
1085 newname = malloc(tcnp->cn_namelen, M_TMPFSNAME, M_WAITOK);
1086 } else
1087 newname = NULL;
1088
1089 /*
1090 * If the node is being moved to another directory, we have to do
1091 * the move.
1092 */
1093 if (fdnode != tdnode) {
1094 /*
1095 * In case we are moving a directory, we have to adjust its
1096 * parent to point to the new parent.
1097 */
1098 if (de->td_node->tn_type == VDIR) {
1099 struct tmpfs_node *n;
1100
1101 /*
1102 * Ensure the target directory is not a child of the
1103 * directory being moved. Otherwise, we'd end up
1104 * with stale nodes.
1105 */
1106 n = tdnode;
1107 /*
1108 * TMPFS_LOCK guaranties that no nodes are freed while
1109 * traversing the list. Nodes can only be marked as
1110 * removed: tn_parent == NULL.
1111 */
1112 TMPFS_LOCK(tmp);
1113 TMPFS_NODE_LOCK(n);
1114 while (n != n->tn_dir.tn_parent) {
1115 struct tmpfs_node *parent;
1116
1117 if (n == fnode) {
1118 TMPFS_NODE_UNLOCK(n);
1119 TMPFS_UNLOCK(tmp);
1120 error = EINVAL;
1121 if (newname != NULL)
1122 free(newname, M_TMPFSNAME);
1123 goto out_locked;
1124 }
1125 parent = n->tn_dir.tn_parent;
1126 TMPFS_NODE_UNLOCK(n);
1127 if (parent == NULL) {
1128 n = NULL;
1129 break;
1130 }
1131 TMPFS_NODE_LOCK(parent);
1132 if (parent->tn_dir.tn_parent == NULL) {
1133 TMPFS_NODE_UNLOCK(parent);
1134 n = NULL;
1135 break;
1136 }
1137 n = parent;
1138 }
1139 TMPFS_UNLOCK(tmp);
1140 if (n == NULL) {
1141 error = EINVAL;
1142 if (newname != NULL)
1143 free(newname, M_TMPFSNAME);
1144 goto out_locked;
1145 }
1146 TMPFS_NODE_UNLOCK(n);
1147
1148 /* Adjust the parent pointer. */
1149 TMPFS_VALIDATE_DIR(fnode);
1150 TMPFS_NODE_LOCK(de->td_node);
1151 de->td_node->tn_dir.tn_parent = tdnode;
1152 TMPFS_NODE_UNLOCK(de->td_node);
1153
1154 /*
1155 * As a result of changing the target of the '..'
1156 * entry, the link count of the source and target
1157 * directories has to be adjusted.
1158 */
1159 TMPFS_NODE_LOCK(tdnode);
1160 TMPFS_ASSERT_LOCKED(tdnode);
1161 tdnode->tn_links++;
1162 TMPFS_NODE_UNLOCK(tdnode);
1163
1164 TMPFS_NODE_LOCK(fdnode);
1165 TMPFS_ASSERT_LOCKED(fdnode);
1166 fdnode->tn_links--;
1167 TMPFS_NODE_UNLOCK(fdnode);
1168 }
1169 }
1170
1171 /*
1172 * Do the move: just remove the entry from the source directory
1173 * and insert it into the target one.
1174 */
1175 tmpfs_dir_detach(fdvp, de);
1176
1177 if (fcnp->cn_flags & DOWHITEOUT)
1178 tmpfs_dir_whiteout_add(fdvp, fcnp);
1179 if (tcnp->cn_flags & ISWHITEOUT)
1180 tmpfs_dir_whiteout_remove(tdvp, tcnp);
1181
1182 /*
1183 * If the name has changed, we need to make it effective by changing
1184 * it in the directory entry.
1185 */
1186 if (newname != NULL) {
1187 MPASS(tcnp->cn_namelen <= MAXNAMLEN);
1188
1189 free(de->ud.td_name, M_TMPFSNAME);
1190 de->ud.td_name = newname;
1191 tmpfs_dirent_init(de, tcnp->cn_nameptr, tcnp->cn_namelen);
1192
1193 fnode->tn_status |= TMPFS_NODE_CHANGED;
1194 tdnode->tn_status |= TMPFS_NODE_MODIFIED;
1195 }
1196
1197 /*
1198 * If we are overwriting an entry, we have to remove the old one
1199 * from the target directory.
1200 */
1201 if (tvp != NULL) {
1202 struct tmpfs_dirent *tde;
1203
1204 /* Remove the old entry from the target directory. */
1205 tde = tmpfs_dir_lookup(tdnode, tnode, tcnp);
1206 tmpfs_dir_detach(tdvp, tde);
1207
1208 /*
1209 * Free the directory entry we just deleted. Note that the
1210 * node referred by it will not be removed until the vnode is
1211 * really reclaimed.
1212 */
1213 tmpfs_free_dirent(VFS_TO_TMPFS(tvp->v_mount), tde);
1214 }
1215
1216 tmpfs_dir_attach(tdvp, de);
1217
1218 if (tmpfs_use_nc(fvp)) {
1219 cache_vop_rename(fdvp, fvp, tdvp, tvp, fcnp, tcnp);
1220 }
1221
1222 error = 0;
1223
1224 out_locked:
1225 if (fdvp != tdvp && fdvp != tvp)
1226 VOP_UNLOCK(fdvp);
1227
1228 out:
1229 if (want_seqc_end) {
1230 if (tvp != NULL)
1231 vn_seqc_write_end(tvp);
1232 vn_seqc_write_end(tdvp);
1233 vn_seqc_write_end(fvp);
1234 vn_seqc_write_end(fdvp);
1235 }
1236
1237 /*
1238 * Release target nodes.
1239 * XXX: I don't understand when tdvp can be the same as tvp, but
1240 * other code takes care of this...
1241 */
1242 if (tdvp == tvp)
1243 vrele(tdvp);
1244 else
1245 vput(tdvp);
1246 if (tvp != NULL)
1247 vput(tvp);
1248
1249 /* Release source nodes. */
1250 vrele(fdvp);
1251 vrele(fvp);
1252
1253 return (error);
1254 }
1255
1256 static int
1257 tmpfs_mkdir(struct vop_mkdir_args *v)
1258 {
1259 struct vnode *dvp = v->a_dvp;
1260 struct vnode **vpp = v->a_vpp;
1261 struct componentname *cnp = v->a_cnp;
1262 struct vattr *vap = v->a_vap;
1263
1264 MPASS(vap->va_type == VDIR);
1265
1266 return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL);
1267 }
1268
1269 static int
1270 tmpfs_rmdir(struct vop_rmdir_args *v)
1271 {
1272 struct vnode *dvp = v->a_dvp;
1273 struct vnode *vp = v->a_vp;
1274
1275 int error;
1276 struct tmpfs_dirent *de;
1277 struct tmpfs_mount *tmp;
1278 struct tmpfs_node *dnode;
1279 struct tmpfs_node *node;
1280
1281 MPASS(VOP_ISLOCKED(dvp));
1282 MPASS(VOP_ISLOCKED(vp));
1283
1284 tmp = VFS_TO_TMPFS(dvp->v_mount);
1285 dnode = VP_TO_TMPFS_DIR(dvp);
1286 node = VP_TO_TMPFS_DIR(vp);
1287
1288 /* Directories with more than two entries ('.' and '..') cannot be
1289 * removed. */
1290 if (node->tn_size > 0) {
1291 error = ENOTEMPTY;
1292 goto out;
1293 }
1294
1295 if ((dnode->tn_flags & APPEND)
1296 || (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))) {
1297 error = EPERM;
1298 goto out;
1299 }
1300
1301 /* This invariant holds only if we are not trying to remove "..".
1302 * We checked for that above so this is safe now. */
1303 MPASS(node->tn_dir.tn_parent == dnode);
1304
1305 /* Get the directory entry associated with node (vp). This was
1306 * filled by tmpfs_lookup while looking up the entry. */
1307 de = tmpfs_dir_lookup(dnode, node, v->a_cnp);
1308 MPASS(TMPFS_DIRENT_MATCHES(de,
1309 v->a_cnp->cn_nameptr,
1310 v->a_cnp->cn_namelen));
1311
1312 /* Check flags to see if we are allowed to remove the directory. */
1313 if ((dnode->tn_flags & APPEND) != 0 ||
1314 (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) != 0) {
1315 error = EPERM;
1316 goto out;
1317 }
1318
1319 /* Detach the directory entry from the directory (dnode). */
1320 tmpfs_dir_detach(dvp, de);
1321 if (v->a_cnp->cn_flags & DOWHITEOUT)
1322 tmpfs_dir_whiteout_add(dvp, v->a_cnp);
1323
1324 /* No vnode should be allocated for this entry from this point */
1325 TMPFS_NODE_LOCK(node);
1326 node->tn_links--;
1327 node->tn_dir.tn_parent = NULL;
1328 node->tn_status |= TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED;
1329 node->tn_accessed = true;
1330
1331 TMPFS_NODE_UNLOCK(node);
1332
1333 TMPFS_NODE_LOCK(dnode);
1334 dnode->tn_links--;
1335 dnode->tn_status |= TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED;
1336 dnode->tn_accessed = true;
1337 TMPFS_NODE_UNLOCK(dnode);
1338
1339 if (tmpfs_use_nc(dvp)) {
1340 cache_vop_rmdir(dvp, vp);
1341 }
1342
1343 /* Free the directory entry we just deleted. Note that the node
1344 * referred by it will not be removed until the vnode is really
1345 * reclaimed. */
1346 tmpfs_free_dirent(tmp, de);
1347
1348 /* Release the deleted vnode (will destroy the node, notify
1349 * interested parties and clean it from the cache). */
1350
1351 dnode->tn_status |= TMPFS_NODE_CHANGED;
1352 tmpfs_update(dvp);
1353
1354 error = 0;
1355
1356 out:
1357 return error;
1358 }
1359
1360 static int
1361 tmpfs_symlink(struct vop_symlink_args *v)
1362 {
1363 struct vnode *dvp = v->a_dvp;
1364 struct vnode **vpp = v->a_vpp;
1365 struct componentname *cnp = v->a_cnp;
1366 struct vattr *vap = v->a_vap;
1367 const char *target = v->a_target;
1368
1369 #ifdef notyet /* XXX FreeBSD BUG: kern_symlink is not setting VLNK */
1370 MPASS(vap->va_type == VLNK);
1371 #else
1372 vap->va_type = VLNK;
1373 #endif
1374
1375 return tmpfs_alloc_file(dvp, vpp, vap, cnp, target);
1376 }
1377
1378 static int
1379 tmpfs_readdir(struct vop_readdir_args *va)
1380 {
1381 struct vnode *vp;
1382 struct uio *uio;
1383 struct tmpfs_mount *tm;
1384 struct tmpfs_node *node;
1385 u_long **cookies;
1386 int *eofflag, *ncookies;
1387 ssize_t startresid;
1388 int error, maxcookies;
1389
1390 vp = va->a_vp;
1391 uio = va->a_uio;
1392 eofflag = va->a_eofflag;
1393 cookies = va->a_cookies;
1394 ncookies = va->a_ncookies;
1395
1396 /* This operation only makes sense on directory nodes. */
1397 if (vp->v_type != VDIR)
1398 return ENOTDIR;
1399
1400 maxcookies = 0;
1401 node = VP_TO_TMPFS_DIR(vp);
1402 tm = VFS_TO_TMPFS(vp->v_mount);
1403
1404 startresid = uio->uio_resid;
1405
1406 /* Allocate cookies for NFS and compat modules. */
1407 if (cookies != NULL && ncookies != NULL) {
1408 maxcookies = howmany(node->tn_size,
1409 sizeof(struct tmpfs_dirent)) + 2;
1410 *cookies = malloc(maxcookies * sizeof(**cookies), M_TEMP,
1411 M_WAITOK);
1412 *ncookies = 0;
1413 }
1414
1415 if (cookies == NULL)
1416 error = tmpfs_dir_getdents(tm, node, uio, 0, NULL, NULL);
1417 else
1418 error = tmpfs_dir_getdents(tm, node, uio, maxcookies, *cookies,
1419 ncookies);
1420
1421 /* Buffer was filled without hitting EOF. */
1422 if (error == EJUSTRETURN)
1423 error = (uio->uio_resid != startresid) ? 0 : EINVAL;
1424
1425 if (error != 0 && cookies != NULL && ncookies != NULL) {
1426 free(*cookies, M_TEMP);
1427 *cookies = NULL;
1428 *ncookies = 0;
1429 }
1430
1431 if (eofflag != NULL)
1432 *eofflag =
1433 (error == 0 && uio->uio_offset == TMPFS_DIRCOOKIE_EOF);
1434
1435 return error;
1436 }
1437
1438 static int
1439 tmpfs_readlink(struct vop_readlink_args *v)
1440 {
1441 struct vnode *vp = v->a_vp;
1442 struct uio *uio = v->a_uio;
1443
1444 int error;
1445 struct tmpfs_node *node;
1446
1447 MPASS(uio->uio_offset == 0);
1448 MPASS(vp->v_type == VLNK);
1449
1450 node = VP_TO_TMPFS_NODE(vp);
1451
1452 error = uiomove(node->tn_link_target, MIN(node->tn_size, uio->uio_resid),
1453 uio);
1454 tmpfs_set_accessed(VFS_TO_TMPFS(vp->v_mount), node);
1455
1456 return (error);
1457 }
1458
1459 /*
1460 * VOP_FPLOOKUP_SYMLINK routines are subject to special circumstances, see
1461 * the comment above cache_fplookup for details.
1462 *
1463 * Check tmpfs_alloc_node for tmpfs-specific synchronisation notes.
1464 */
1465 static int
1466 tmpfs_fplookup_symlink(struct vop_fplookup_symlink_args *v)
1467 {
1468 struct vnode *vp;
1469 struct tmpfs_node *node;
1470 char *symlink;
1471
1472 vp = v->a_vp;
1473 node = VP_TO_TMPFS_NODE_SMR(vp);
1474 if (__predict_false(node == NULL))
1475 return (EAGAIN);
1476 if (!atomic_load_char(&node->tn_link_smr))
1477 return (EAGAIN);
1478 symlink = atomic_load_ptr(&node->tn_link_target);
1479 if (symlink == NULL)
1480 return (EAGAIN);
1481
1482 return (cache_symlink_resolve(v->a_fpl, symlink, node->tn_size));
1483 }
1484
1485 static int
1486 tmpfs_inactive(struct vop_inactive_args *v)
1487 {
1488 struct vnode *vp;
1489 struct tmpfs_node *node;
1490
1491 vp = v->a_vp;
1492 node = VP_TO_TMPFS_NODE(vp);
1493 if (node->tn_links == 0)
1494 vrecycle(vp);
1495 else
1496 tmpfs_check_mtime(vp);
1497 return (0);
1498 }
1499
1500 static int
1501 tmpfs_need_inactive(struct vop_need_inactive_args *ap)
1502 {
1503 struct vnode *vp;
1504 struct tmpfs_node *node;
1505 struct vm_object *obj;
1506
1507 vp = ap->a_vp;
1508 node = VP_TO_TMPFS_NODE(vp);
1509 if (node->tn_links == 0)
1510 goto need;
1511 if (vp->v_type == VREG) {
1512 obj = vp->v_object;
1513 if (obj->generation != obj->cleangeneration)
1514 goto need;
1515 }
1516 return (0);
1517 need:
1518 return (1);
1519 }
1520
1521 int
1522 tmpfs_reclaim(struct vop_reclaim_args *v)
1523 {
1524 struct vnode *vp;
1525 struct tmpfs_mount *tmp;
1526 struct tmpfs_node *node;
1527 bool unlock, tm_locked;
1528
1529 vp = v->a_vp;
1530 node = VP_TO_TMPFS_NODE(vp);
1531 tmp = VFS_TO_TMPFS(vp->v_mount);
1532 tm_locked = false;
1533
1534 if (vp->v_type == VREG)
1535 tmpfs_destroy_vobject(vp, node->tn_reg.tn_aobj);
1536 vp->v_object = NULL;
1537
1538 relock:
1539 TMPFS_NODE_LOCK(node);
1540 if (!tm_locked && node->tn_links == 0 &&
1541 (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) {
1542 TMPFS_NODE_UNLOCK(node);
1543 TMPFS_LOCK(tmp);
1544 tm_locked = true;
1545 goto relock;
1546 }
1547 tmpfs_free_vp(vp);
1548
1549 /*
1550 * If the node referenced by this vnode was deleted by the user,
1551 * we must free its associated data structures (now that the vnode
1552 * is being reclaimed).
1553 */
1554 if (node->tn_links == 0 &&
1555 (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) {
1556 MPASS(tm_locked);
1557 node->tn_vpstate = TMPFS_VNODE_DOOMED;
1558 unlock = !tmpfs_free_node_locked(tmp, node, true);
1559 } else {
1560 unlock = true;
1561 }
1562
1563 if (unlock) {
1564 TMPFS_NODE_UNLOCK(node);
1565 if (tm_locked)
1566 TMPFS_UNLOCK(tmp);
1567 }
1568
1569 MPASS(vp->v_data == NULL);
1570 return (0);
1571 }
1572
1573 int
1574 tmpfs_print(struct vop_print_args *v)
1575 {
1576 struct vnode *vp = v->a_vp;
1577
1578 struct tmpfs_node *node;
1579
1580 node = VP_TO_TMPFS_NODE(vp);
1581
1582 printf("tag VT_TMPFS, tmpfs_node %p, flags 0x%lx, links %jd\n",
1583 node, node->tn_flags, (uintmax_t)node->tn_links);
1584 printf("\tmode 0%o, owner %d, group %d, size %jd, status 0x%x\n",
1585 node->tn_mode, node->tn_uid, node->tn_gid,
1586 (intmax_t)node->tn_size, node->tn_status);
1587
1588 if (vp->v_type == VFIFO)
1589 fifo_printinfo(vp);
1590
1591 printf("\n");
1592
1593 return 0;
1594 }
1595
1596 int
1597 tmpfs_pathconf(struct vop_pathconf_args *v)
1598 {
1599 struct vnode *vp = v->a_vp;
1600 int name = v->a_name;
1601 long *retval = v->a_retval;
1602
1603 int error;
1604
1605 error = 0;
1606
1607 switch (name) {
1608 case _PC_LINK_MAX:
1609 *retval = TMPFS_LINK_MAX;
1610 break;
1611
1612 case _PC_NAME_MAX:
1613 *retval = NAME_MAX;
1614 break;
1615
1616 case _PC_PIPE_BUF:
1617 if (vp->v_type == VDIR || vp->v_type == VFIFO)
1618 *retval = PIPE_BUF;
1619 else
1620 error = EINVAL;
1621 break;
1622
1623 case _PC_CHOWN_RESTRICTED:
1624 *retval = 1;
1625 break;
1626
1627 case _PC_NO_TRUNC:
1628 *retval = 1;
1629 break;
1630
1631 case _PC_SYNC_IO:
1632 *retval = 1;
1633 break;
1634
1635 case _PC_FILESIZEBITS:
1636 *retval = 64;
1637 break;
1638
1639 default:
1640 error = vop_stdpathconf(v);
1641 }
1642
1643 return error;
1644 }
1645
1646 static int
1647 tmpfs_vptofh(struct vop_vptofh_args *ap)
1648 /*
1649 vop_vptofh {
1650 IN struct vnode *a_vp;
1651 IN struct fid *a_fhp;
1652 };
1653 */
1654 {
1655 struct tmpfs_fid_data tfd;
1656 struct tmpfs_node *node;
1657 struct fid *fhp;
1658
1659 node = VP_TO_TMPFS_NODE(ap->a_vp);
1660 fhp = ap->a_fhp;
1661 fhp->fid_len = sizeof(tfd);
1662
1663 /*
1664 * Copy into fid_data from the stack to avoid unaligned pointer use.
1665 * See the comment in sys/mount.h on struct fid for details.
1666 */
1667 tfd.tfd_id = node->tn_id;
1668 tfd.tfd_gen = node->tn_gen;
1669 memcpy(fhp->fid_data, &tfd, fhp->fid_len);
1670
1671 return (0);
1672 }
1673
1674 static int
1675 tmpfs_whiteout(struct vop_whiteout_args *ap)
1676 {
1677 struct vnode *dvp = ap->a_dvp;
1678 struct componentname *cnp = ap->a_cnp;
1679 struct tmpfs_dirent *de;
1680
1681 switch (ap->a_flags) {
1682 case LOOKUP:
1683 return (0);
1684 case CREATE:
1685 de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(dvp), NULL, cnp);
1686 if (de != NULL)
1687 return (de->td_node == NULL ? 0 : EEXIST);
1688 return (tmpfs_dir_whiteout_add(dvp, cnp));
1689 case DELETE:
1690 tmpfs_dir_whiteout_remove(dvp, cnp);
1691 return (0);
1692 default:
1693 panic("tmpfs_whiteout: unknown op");
1694 }
1695 }
1696
1697 static int
1698 tmpfs_vptocnp_dir(struct tmpfs_node *tn, struct tmpfs_node *tnp,
1699 struct tmpfs_dirent **pde)
1700 {
1701 struct tmpfs_dir_cursor dc;
1702 struct tmpfs_dirent *de;
1703
1704 for (de = tmpfs_dir_first(tnp, &dc); de != NULL;
1705 de = tmpfs_dir_next(tnp, &dc)) {
1706 if (de->td_node == tn) {
1707 *pde = de;
1708 return (0);
1709 }
1710 }
1711 return (ENOENT);
1712 }
1713
1714 static int
1715 tmpfs_vptocnp_fill(struct vnode *vp, struct tmpfs_node *tn,
1716 struct tmpfs_node *tnp, char *buf, size_t *buflen, struct vnode **dvp)
1717 {
1718 struct tmpfs_dirent *de;
1719 int error, i;
1720
1721 error = vn_vget_ino_gen(vp, tmpfs_vn_get_ino_alloc, tnp, LK_SHARED,
1722 dvp);
1723 if (error != 0)
1724 return (error);
1725 error = tmpfs_vptocnp_dir(tn, tnp, &de);
1726 if (error == 0) {
1727 i = *buflen;
1728 i -= de->td_namelen;
1729 if (i < 0) {
1730 error = ENOMEM;
1731 } else {
1732 bcopy(de->ud.td_name, buf + i, de->td_namelen);
1733 *buflen = i;
1734 }
1735 }
1736 if (error == 0) {
1737 if (vp != *dvp)
1738 VOP_UNLOCK(*dvp);
1739 } else {
1740 if (vp != *dvp)
1741 vput(*dvp);
1742 else
1743 vrele(vp);
1744 }
1745 return (error);
1746 }
1747
1748 static int
1749 tmpfs_vptocnp(struct vop_vptocnp_args *ap)
1750 {
1751 struct vnode *vp, **dvp;
1752 struct tmpfs_node *tn, *tnp, *tnp1;
1753 struct tmpfs_dirent *de;
1754 struct tmpfs_mount *tm;
1755 char *buf;
1756 size_t *buflen;
1757 int error;
1758
1759 vp = ap->a_vp;
1760 dvp = ap->a_vpp;
1761 buf = ap->a_buf;
1762 buflen = ap->a_buflen;
1763
1764 tm = VFS_TO_TMPFS(vp->v_mount);
1765 tn = VP_TO_TMPFS_NODE(vp);
1766 if (tn->tn_type == VDIR) {
1767 tnp = tn->tn_dir.tn_parent;
1768 if (tnp == NULL)
1769 return (ENOENT);
1770 tmpfs_ref_node(tnp);
1771 error = tmpfs_vptocnp_fill(vp, tn, tn->tn_dir.tn_parent, buf,
1772 buflen, dvp);
1773 tmpfs_free_node(tm, tnp);
1774 return (error);
1775 }
1776 restart:
1777 TMPFS_LOCK(tm);
1778 restart_locked:
1779 LIST_FOREACH_SAFE(tnp, &tm->tm_nodes_used, tn_entries, tnp1) {
1780 if (tnp->tn_type != VDIR)
1781 continue;
1782 TMPFS_NODE_LOCK(tnp);
1783 tmpfs_ref_node(tnp);
1784
1785 /*
1786 * tn_vnode cannot be instantiated while we hold the
1787 * node lock, so the directory cannot be changed while
1788 * we iterate over it. Do this to avoid instantiating
1789 * vnode for directories which cannot point to our
1790 * node.
1791 */
1792 error = tnp->tn_vnode == NULL ? tmpfs_vptocnp_dir(tn, tnp,
1793 &de) : 0;
1794
1795 if (error == 0) {
1796 TMPFS_NODE_UNLOCK(tnp);
1797 TMPFS_UNLOCK(tm);
1798 error = tmpfs_vptocnp_fill(vp, tn, tnp, buf, buflen,
1799 dvp);
1800 if (error == 0) {
1801 tmpfs_free_node(tm, tnp);
1802 return (0);
1803 }
1804 if (VN_IS_DOOMED(vp)) {
1805 tmpfs_free_node(tm, tnp);
1806 return (ENOENT);
1807 }
1808 TMPFS_LOCK(tm);
1809 TMPFS_NODE_LOCK(tnp);
1810 }
1811 if (tmpfs_free_node_locked(tm, tnp, false)) {
1812 goto restart;
1813 } else {
1814 KASSERT(tnp->tn_refcount > 0,
1815 ("node %p refcount zero", tnp));
1816 if (tnp->tn_attached) {
1817 tnp1 = LIST_NEXT(tnp, tn_entries);
1818 TMPFS_NODE_UNLOCK(tnp);
1819 } else {
1820 TMPFS_NODE_UNLOCK(tnp);
1821 goto restart_locked;
1822 }
1823 }
1824 }
1825 TMPFS_UNLOCK(tm);
1826 return (ENOENT);
1827 }
1828
1829 /*
1830 * Vnode operations vector used for files stored in a tmpfs file system.
1831 */
1832 struct vop_vector tmpfs_vnodeop_entries = {
1833 .vop_default = &default_vnodeops,
1834 .vop_lookup = vfs_cache_lookup,
1835 .vop_cachedlookup = tmpfs_cached_lookup,
1836 .vop_create = tmpfs_create,
1837 .vop_mknod = tmpfs_mknod,
1838 .vop_open = tmpfs_open,
1839 .vop_close = tmpfs_close,
1840 .vop_fplookup_vexec = tmpfs_fplookup_vexec,
1841 .vop_fplookup_symlink = tmpfs_fplookup_symlink,
1842 .vop_access = tmpfs_access,
1843 .vop_stat = tmpfs_stat,
1844 .vop_getattr = tmpfs_getattr,
1845 .vop_setattr = tmpfs_setattr,
1846 .vop_read = tmpfs_read,
1847 .vop_read_pgcache = tmpfs_read_pgcache,
1848 .vop_write = tmpfs_write,
1849 .vop_fsync = tmpfs_fsync,
1850 .vop_remove = tmpfs_remove,
1851 .vop_link = tmpfs_link,
1852 .vop_rename = tmpfs_rename,
1853 .vop_mkdir = tmpfs_mkdir,
1854 .vop_rmdir = tmpfs_rmdir,
1855 .vop_symlink = tmpfs_symlink,
1856 .vop_readdir = tmpfs_readdir,
1857 .vop_readlink = tmpfs_readlink,
1858 .vop_inactive = tmpfs_inactive,
1859 .vop_need_inactive = tmpfs_need_inactive,
1860 .vop_reclaim = tmpfs_reclaim,
1861 .vop_print = tmpfs_print,
1862 .vop_pathconf = tmpfs_pathconf,
1863 .vop_vptofh = tmpfs_vptofh,
1864 .vop_whiteout = tmpfs_whiteout,
1865 .vop_bmap = VOP_EOPNOTSUPP,
1866 .vop_vptocnp = tmpfs_vptocnp,
1867 .vop_lock1 = vop_lock,
1868 .vop_unlock = vop_unlock,
1869 .vop_islocked = vop_islocked,
1870 };
1871 VFS_VOP_VECTOR_REGISTER(tmpfs_vnodeop_entries);
1872
1873 /*
1874 * Same vector for mounts which do not use namecache.
1875 */
1876 struct vop_vector tmpfs_vnodeop_nonc_entries = {
1877 .vop_default = &tmpfs_vnodeop_entries,
1878 .vop_lookup = tmpfs_lookup,
1879 };
1880 VFS_VOP_VECTOR_REGISTER(tmpfs_vnodeop_nonc_entries);
Cache object: ebe4a462c7d882379beccd93856dacf0
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