1 /*-
2 * Copyright (c) 2001 Dag-Erling Coïdan Smørgrav
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer
10 * in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD: releng/8.3/sys/fs/pseudofs/pseudofs_vnops.c 231089 2012-02-06 17:28:55Z jh $");
31
32 #include "opt_pseudofs.h"
33
34 #include <sys/param.h>
35 #include <sys/kernel.h>
36 #include <sys/systm.h>
37 #include <sys/ctype.h>
38 #include <sys/dirent.h>
39 #include <sys/fcntl.h>
40 #include <sys/limits.h>
41 #include <sys/lock.h>
42 #include <sys/malloc.h>
43 #include <sys/mount.h>
44 #include <sys/mutex.h>
45 #include <sys/namei.h>
46 #include <sys/proc.h>
47 #include <sys/sbuf.h>
48 #include <sys/sx.h>
49 #include <sys/sysctl.h>
50 #include <sys/vnode.h>
51
52 #include <fs/pseudofs/pseudofs.h>
53 #include <fs/pseudofs/pseudofs_internal.h>
54
55 #define KASSERT_PN_IS_DIR(pn) \
56 KASSERT((pn)->pn_type == pfstype_root || \
57 (pn)->pn_type == pfstype_dir || \
58 (pn)->pn_type == pfstype_procdir, \
59 ("%s(): VDIR vnode refers to non-directory pfs_node", __func__))
60
61 #define KASSERT_PN_IS_FILE(pn) \
62 KASSERT((pn)->pn_type == pfstype_file, \
63 ("%s(): VREG vnode refers to non-file pfs_node", __func__))
64
65 #define KASSERT_PN_IS_LINK(pn) \
66 KASSERT((pn)->pn_type == pfstype_symlink, \
67 ("%s(): VLNK vnode refers to non-link pfs_node", __func__))
68
69 /*
70 * Returns the fileno, adjusted for target pid
71 */
72 static uint32_t
73 pn_fileno(struct pfs_node *pn, pid_t pid)
74 {
75
76 KASSERT(pn->pn_fileno > 0,
77 ("%s(): no fileno allocated", __func__));
78 if (pid != NO_PID)
79 return (pn->pn_fileno * NO_PID + pid);
80 return (pn->pn_fileno);
81 }
82
83 /*
84 * Returns non-zero if given file is visible to given thread.
85 */
86 static int
87 pfs_visible_proc(struct thread *td, struct pfs_node *pn, struct proc *proc)
88 {
89 int visible;
90
91 if (proc == NULL)
92 return (0);
93
94 PROC_LOCK_ASSERT(proc, MA_OWNED);
95
96 visible = ((proc->p_flag & P_WEXIT) == 0);
97 if (visible)
98 visible = (p_cansee(td, proc) == 0);
99 if (visible && pn->pn_vis != NULL)
100 visible = pn_vis(td, proc, pn);
101 if (!visible)
102 return (0);
103 return (1);
104 }
105
106 static int
107 pfs_visible(struct thread *td, struct pfs_node *pn, pid_t pid, struct proc **p)
108 {
109 struct proc *proc;
110
111 PFS_TRACE(("%s (pid: %d, req: %d)",
112 pn->pn_name, pid, td->td_proc->p_pid));
113
114 if (p)
115 *p = NULL;
116 if (pid == NO_PID)
117 PFS_RETURN (1);
118 if ((proc = pfind(pid)) == NULL)
119 PFS_RETURN (0);
120 if (pfs_visible_proc(td, pn, proc)) {
121 if (p)
122 *p = proc;
123 else
124 PROC_UNLOCK(proc);
125 PFS_RETURN (1);
126 }
127 PROC_UNLOCK(proc);
128 PFS_RETURN (0);
129 }
130
131 /*
132 * Verify permissions
133 */
134 static int
135 pfs_access(struct vop_access_args *va)
136 {
137 struct vnode *vn = va->a_vp;
138 struct pfs_vdata *pvd = vn->v_data;
139 struct vattr vattr;
140 int error;
141
142 PFS_TRACE(("%s", pvd->pvd_pn->pn_name));
143 (void)pvd;
144
145 error = VOP_GETATTR(vn, &vattr, va->a_cred);
146 if (error)
147 PFS_RETURN (error);
148 error = vaccess(vn->v_type, vattr.va_mode, vattr.va_uid,
149 vattr.va_gid, va->a_accmode, va->a_cred, NULL);
150 PFS_RETURN (error);
151 }
152
153 /*
154 * Close a file or directory
155 */
156 static int
157 pfs_close(struct vop_close_args *va)
158 {
159 struct vnode *vn = va->a_vp;
160 struct pfs_vdata *pvd = vn->v_data;
161 struct pfs_node *pn = pvd->pvd_pn;
162 struct proc *proc;
163 int error;
164
165 PFS_TRACE(("%s", pn->pn_name));
166 pfs_assert_not_owned(pn);
167
168 /*
169 * Do nothing unless this is the last close and the node has a
170 * last-close handler.
171 */
172 if (vrefcnt(vn) > 1 || pn->pn_close == NULL)
173 PFS_RETURN (0);
174
175 if (pvd->pvd_pid != NO_PID) {
176 proc = pfind(pvd->pvd_pid);
177 } else {
178 proc = NULL;
179 }
180
181 error = pn_close(va->a_td, proc, pn);
182
183 if (proc != NULL)
184 PROC_UNLOCK(proc);
185
186 PFS_RETURN (error);
187 }
188
189 /*
190 * Get file attributes
191 */
192 static int
193 pfs_getattr(struct vop_getattr_args *va)
194 {
195 struct vnode *vn = va->a_vp;
196 struct pfs_vdata *pvd = vn->v_data;
197 struct pfs_node *pn = pvd->pvd_pn;
198 struct vattr *vap = va->a_vap;
199 struct proc *proc;
200 int error = 0;
201
202 PFS_TRACE(("%s", pn->pn_name));
203 pfs_assert_not_owned(pn);
204
205 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc))
206 PFS_RETURN (ENOENT);
207
208 vap->va_type = vn->v_type;
209 vap->va_fileid = pn_fileno(pn, pvd->pvd_pid);
210 vap->va_flags = 0;
211 vap->va_blocksize = PAGE_SIZE;
212 vap->va_bytes = vap->va_size = 0;
213 vap->va_filerev = 0;
214 vap->va_fsid = vn->v_mount->mnt_stat.f_fsid.val[0];
215 vap->va_nlink = 1;
216 nanotime(&vap->va_ctime);
217 vap->va_atime = vap->va_mtime = vap->va_ctime;
218
219 switch (pn->pn_type) {
220 case pfstype_procdir:
221 case pfstype_root:
222 case pfstype_dir:
223 #if 0
224 pfs_lock(pn);
225 /* compute link count */
226 pfs_unlock(pn);
227 #endif
228 vap->va_mode = 0555;
229 break;
230 case pfstype_file:
231 case pfstype_symlink:
232 vap->va_mode = 0444;
233 break;
234 default:
235 printf("shouldn't be here!\n");
236 vap->va_mode = 0;
237 break;
238 }
239
240 if (proc != NULL) {
241 vap->va_uid = proc->p_ucred->cr_ruid;
242 vap->va_gid = proc->p_ucred->cr_rgid;
243 } else {
244 vap->va_uid = 0;
245 vap->va_gid = 0;
246 }
247
248 if (pn->pn_attr != NULL)
249 error = pn_attr(curthread, proc, pn, vap);
250
251 if(proc != NULL)
252 PROC_UNLOCK(proc);
253
254 PFS_RETURN (error);
255 }
256
257 /*
258 * Perform an ioctl
259 */
260 static int
261 pfs_ioctl(struct vop_ioctl_args *va)
262 {
263 struct vnode *vn;
264 struct pfs_vdata *pvd;
265 struct pfs_node *pn;
266 struct proc *proc;
267 int error;
268
269 vn = va->a_vp;
270 vn_lock(vn, LK_SHARED | LK_RETRY);
271 if (vn->v_iflag & VI_DOOMED) {
272 VOP_UNLOCK(vn, 0);
273 return (EBADF);
274 }
275 pvd = vn->v_data;
276 pn = pvd->pvd_pn;
277
278 PFS_TRACE(("%s: %lx", pn->pn_name, va->a_command));
279 pfs_assert_not_owned(pn);
280
281 if (vn->v_type != VREG) {
282 VOP_UNLOCK(vn, 0);
283 PFS_RETURN (EINVAL);
284 }
285 KASSERT_PN_IS_FILE(pn);
286
287 if (pn->pn_ioctl == NULL) {
288 VOP_UNLOCK(vn, 0);
289 PFS_RETURN (ENOTTY);
290 }
291
292 /*
293 * This is necessary because process' privileges may
294 * have changed since the open() call.
295 */
296 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) {
297 VOP_UNLOCK(vn, 0);
298 PFS_RETURN (EIO);
299 }
300
301 error = pn_ioctl(curthread, proc, pn, va->a_command, va->a_data);
302
303 if (proc != NULL)
304 PROC_UNLOCK(proc);
305
306 VOP_UNLOCK(vn, 0);
307 PFS_RETURN (error);
308 }
309
310 /*
311 * Perform getextattr
312 */
313 static int
314 pfs_getextattr(struct vop_getextattr_args *va)
315 {
316 struct vnode *vn = va->a_vp;
317 struct pfs_vdata *pvd = vn->v_data;
318 struct pfs_node *pn = pvd->pvd_pn;
319 struct proc *proc;
320 int error;
321
322 PFS_TRACE(("%s", pn->pn_name));
323 pfs_assert_not_owned(pn);
324
325 /*
326 * This is necessary because either process' privileges may
327 * have changed since the open() call.
328 */
329 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc))
330 PFS_RETURN (EIO);
331
332 if (pn->pn_getextattr == NULL)
333 error = EOPNOTSUPP;
334 else
335 error = pn_getextattr(curthread, proc, pn,
336 va->a_attrnamespace, va->a_name, va->a_uio,
337 va->a_size, va->a_cred);
338
339 if (proc != NULL)
340 PROC_UNLOCK(proc);
341
342 PFS_RETURN (error);
343 }
344
345 /*
346 * Convert a vnode to its component name
347 */
348 static int
349 pfs_vptocnp(struct vop_vptocnp_args *ap)
350 {
351 struct vnode *vp = ap->a_vp;
352 struct vnode **dvp = ap->a_vpp;
353 struct pfs_vdata *pvd = vp->v_data;
354 struct pfs_node *pd = pvd->pvd_pn;
355 struct pfs_node *pn;
356 struct mount *mp;
357 char *buf = ap->a_buf;
358 int *buflen = ap->a_buflen;
359 char pidbuf[PFS_NAMELEN];
360 pid_t pid = pvd->pvd_pid;
361 int len, i, error, locked;
362
363 i = *buflen;
364 error = 0;
365
366 pfs_lock(pd);
367
368 if (vp->v_type == VDIR && pd->pn_type == pfstype_root) {
369 *dvp = vp;
370 vhold(*dvp);
371 pfs_unlock(pd);
372 PFS_RETURN (0);
373 } else if (vp->v_type == VDIR && pd->pn_type == pfstype_procdir) {
374 len = snprintf(pidbuf, sizeof(pidbuf), "%d", pid);
375 i -= len;
376 if (i < 0) {
377 error = ENOMEM;
378 goto failed;
379 }
380 bcopy(pidbuf, buf + i, len);
381 } else {
382 len = strlen(pd->pn_name);
383 i -= len;
384 if (i < 0) {
385 error = ENOMEM;
386 goto failed;
387 }
388 bcopy(pd->pn_name, buf + i, len);
389 }
390
391 pn = pd->pn_parent;
392 pfs_unlock(pd);
393
394 mp = vp->v_mount;
395 error = vfs_busy(mp, 0);
396 if (error)
397 return (error);
398
399 /*
400 * vp is held by caller.
401 */
402 locked = VOP_ISLOCKED(vp);
403 VOP_UNLOCK(vp, 0);
404
405 error = pfs_vncache_alloc(mp, dvp, pn, pid);
406 if (error) {
407 vn_lock(vp, locked | LK_RETRY);
408 vfs_unbusy(mp);
409 PFS_RETURN(error);
410 }
411
412 *buflen = i;
413 vhold(*dvp);
414 vput(*dvp);
415 vn_lock(vp, locked | LK_RETRY);
416 vfs_unbusy(mp);
417
418 PFS_RETURN (0);
419 failed:
420 pfs_unlock(pd);
421 PFS_RETURN(error);
422 }
423
424 /*
425 * Look up a file or directory
426 */
427 static int
428 pfs_lookup(struct vop_cachedlookup_args *va)
429 {
430 struct vnode *vn = va->a_dvp;
431 struct vnode **vpp = va->a_vpp;
432 struct componentname *cnp = va->a_cnp;
433 struct pfs_vdata *pvd = vn->v_data;
434 struct pfs_node *pd = pvd->pvd_pn;
435 struct pfs_node *pn, *pdn = NULL;
436 pid_t pid = pvd->pvd_pid;
437 char *pname;
438 int error, i, namelen, visible;
439
440 PFS_TRACE(("%.*s", (int)cnp->cn_namelen, cnp->cn_nameptr));
441 pfs_assert_not_owned(pd);
442
443 if (vn->v_type != VDIR)
444 PFS_RETURN (ENOTDIR);
445 KASSERT_PN_IS_DIR(pd);
446
447 error = VOP_ACCESS(vn, VEXEC, cnp->cn_cred, cnp->cn_thread);
448 if (error)
449 PFS_RETURN (error);
450
451 /*
452 * Don't support DELETE or RENAME. CREATE is supported so
453 * that O_CREAT will work, but the lookup will still fail if
454 * the file does not exist.
455 */
456 if ((cnp->cn_flags & ISLASTCN) &&
457 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))
458 PFS_RETURN (EOPNOTSUPP);
459
460 /* shortcut: check if the name is too long */
461 if (cnp->cn_namelen >= PFS_NAMELEN)
462 PFS_RETURN (ENOENT);
463
464 /* check that parent directory is visible... */
465 if (!pfs_visible(curthread, pd, pvd->pvd_pid, NULL))
466 PFS_RETURN (ENOENT);
467
468 /* self */
469 namelen = cnp->cn_namelen;
470 pname = cnp->cn_nameptr;
471 if (namelen == 1 && pname[0] == '.') {
472 pn = pd;
473 *vpp = vn;
474 VREF(vn);
475 PFS_RETURN (0);
476 }
477
478 /* parent */
479 if (cnp->cn_flags & ISDOTDOT) {
480 if (pd->pn_type == pfstype_root)
481 PFS_RETURN (EIO);
482 VOP_UNLOCK(vn, 0);
483 KASSERT(pd->pn_parent != NULL,
484 ("%s(): non-root directory has no parent", __func__));
485 /*
486 * This one is tricky. Descendents of procdir nodes
487 * inherit their parent's process affinity, but
488 * there's no easy reverse mapping. For simplicity,
489 * we assume that if this node is a procdir, its
490 * parent isn't (which is correct as long as
491 * descendents of procdir nodes are never procdir
492 * nodes themselves)
493 */
494 if (pd->pn_type == pfstype_procdir)
495 pid = NO_PID;
496 pfs_lock(pd);
497 pn = pd->pn_parent;
498 pfs_unlock(pd);
499 goto got_pnode;
500 }
501
502 pfs_lock(pd);
503
504 /* named node */
505 for (pn = pd->pn_nodes; pn != NULL; pn = pn->pn_next)
506 if (pn->pn_type == pfstype_procdir)
507 pdn = pn;
508 else if (pn->pn_name[namelen] == '\0' &&
509 bcmp(pname, pn->pn_name, namelen) == 0) {
510 pfs_unlock(pd);
511 goto got_pnode;
512 }
513
514 /* process dependent node */
515 if ((pn = pdn) != NULL) {
516 pid = 0;
517 for (pid = 0, i = 0; i < namelen && isdigit(pname[i]); ++i)
518 if ((pid = pid * 10 + pname[i] - '') > PID_MAX)
519 break;
520 if (i == cnp->cn_namelen) {
521 pfs_unlock(pd);
522 goto got_pnode;
523 }
524 }
525
526 pfs_unlock(pd);
527
528 PFS_RETURN (ENOENT);
529
530 got_pnode:
531 pfs_assert_not_owned(pd);
532 pfs_assert_not_owned(pn);
533 visible = pfs_visible(curthread, pn, pid, NULL);
534 if (!visible) {
535 error = ENOENT;
536 goto failed;
537 }
538
539 error = pfs_vncache_alloc(vn->v_mount, vpp, pn, pid);
540 if (error)
541 goto failed;
542
543 if (cnp->cn_flags & ISDOTDOT)
544 vn_lock(vn, LK_EXCLUSIVE|LK_RETRY);
545 if (cnp->cn_flags & MAKEENTRY && !(vn->v_iflag & VI_DOOMED))
546 cache_enter(vn, *vpp, cnp);
547 PFS_RETURN (0);
548 failed:
549 if (cnp->cn_flags & ISDOTDOT)
550 vn_lock(vn, LK_EXCLUSIVE|LK_RETRY);
551 PFS_RETURN(error);
552 }
553
554 /*
555 * Open a file or directory.
556 */
557 static int
558 pfs_open(struct vop_open_args *va)
559 {
560 struct vnode *vn = va->a_vp;
561 struct pfs_vdata *pvd = vn->v_data;
562 struct pfs_node *pn = pvd->pvd_pn;
563 int mode = va->a_mode;
564
565 PFS_TRACE(("%s (mode 0x%x)", pn->pn_name, mode));
566 pfs_assert_not_owned(pn);
567
568 /* check if the requested mode is permitted */
569 if (((mode & FREAD) && !(mode & PFS_RD)) ||
570 ((mode & FWRITE) && !(mode & PFS_WR)))
571 PFS_RETURN (EPERM);
572
573 /* we don't support locking */
574 if ((mode & O_SHLOCK) || (mode & O_EXLOCK))
575 PFS_RETURN (EOPNOTSUPP);
576
577 PFS_RETURN (0);
578 }
579
580 /*
581 * Read from a file
582 */
583 static int
584 pfs_read(struct vop_read_args *va)
585 {
586 struct vnode *vn = va->a_vp;
587 struct pfs_vdata *pvd = vn->v_data;
588 struct pfs_node *pn = pvd->pvd_pn;
589 struct uio *uio = va->a_uio;
590 struct proc *proc;
591 struct sbuf *sb = NULL;
592 int error, locked;
593 unsigned int buflen, offset, resid;
594
595 PFS_TRACE(("%s", pn->pn_name));
596 pfs_assert_not_owned(pn);
597
598 if (vn->v_type != VREG)
599 PFS_RETURN (EINVAL);
600 KASSERT_PN_IS_FILE(pn);
601
602 if (!(pn->pn_flags & PFS_RD))
603 PFS_RETURN (EBADF);
604
605 if (pn->pn_fill == NULL)
606 PFS_RETURN (EIO);
607
608 /*
609 * This is necessary because either process' privileges may
610 * have changed since the open() call.
611 */
612 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc))
613 PFS_RETURN (EIO);
614 if (proc != NULL) {
615 _PHOLD(proc);
616 PROC_UNLOCK(proc);
617 }
618
619 vhold(vn);
620 locked = VOP_ISLOCKED(vn);
621 VOP_UNLOCK(vn, 0);
622
623 if (pn->pn_flags & PFS_RAWRD) {
624 PFS_TRACE(("%zd resid", uio->uio_resid));
625 error = pn_fill(curthread, proc, pn, NULL, uio);
626 PFS_TRACE(("%zd resid", uio->uio_resid));
627 goto ret;
628 }
629
630 /* beaucoup sanity checks so we don't ask for bogus allocation */
631 if (uio->uio_offset < 0 || uio->uio_resid < 0 ||
632 (offset = uio->uio_offset) != uio->uio_offset ||
633 (resid = uio->uio_resid) != uio->uio_resid ||
634 (buflen = offset + resid + 1) < offset || buflen > INT_MAX) {
635 error = EINVAL;
636 goto ret;
637 }
638 if (buflen > MAXPHYS + 1)
639 buflen = MAXPHYS + 1;
640
641 sb = sbuf_new(sb, NULL, buflen, 0);
642 if (sb == NULL) {
643 error = EIO;
644 goto ret;
645 }
646
647 error = pn_fill(curthread, proc, pn, sb, uio);
648
649 if (error) {
650 sbuf_delete(sb);
651 goto ret;
652 }
653
654 sbuf_finish(sb);
655 error = uiomove_frombuf(sbuf_data(sb), sbuf_len(sb), uio);
656 sbuf_delete(sb);
657 ret:
658 vn_lock(vn, locked | LK_RETRY);
659 vdrop(vn);
660 if (proc != NULL)
661 PRELE(proc);
662 PFS_RETURN (error);
663 }
664
665 /*
666 * Iterate through directory entries
667 */
668 static int
669 pfs_iterate(struct thread *td, struct proc *proc, struct pfs_node *pd,
670 struct pfs_node **pn, struct proc **p)
671 {
672 int visible;
673
674 sx_assert(&allproc_lock, SX_SLOCKED);
675 pfs_assert_owned(pd);
676 again:
677 if (*pn == NULL) {
678 /* first node */
679 *pn = pd->pn_nodes;
680 } else if ((*pn)->pn_type != pfstype_procdir) {
681 /* next node */
682 *pn = (*pn)->pn_next;
683 }
684 if (*pn != NULL && (*pn)->pn_type == pfstype_procdir) {
685 /* next process */
686 if (*p == NULL)
687 *p = LIST_FIRST(&allproc);
688 else
689 *p = LIST_NEXT(*p, p_list);
690 /* out of processes: next node */
691 if (*p == NULL)
692 *pn = (*pn)->pn_next;
693 else
694 PROC_LOCK(*p);
695 }
696
697 if ((*pn) == NULL)
698 return (-1);
699
700 if (*p != NULL) {
701 visible = pfs_visible_proc(td, *pn, *p);
702 PROC_UNLOCK(*p);
703 } else if (proc != NULL) {
704 visible = pfs_visible_proc(td, *pn, proc);
705 } else {
706 visible = 1;
707 }
708 if (!visible)
709 goto again;
710
711 return (0);
712 }
713
714 /* Directory entry list */
715 struct pfsentry {
716 STAILQ_ENTRY(pfsentry) link;
717 struct dirent entry;
718 };
719 STAILQ_HEAD(pfsdirentlist, pfsentry);
720
721 /*
722 * Return directory entries.
723 */
724 static int
725 pfs_readdir(struct vop_readdir_args *va)
726 {
727 struct vnode *vn = va->a_vp;
728 struct pfs_vdata *pvd = vn->v_data;
729 struct pfs_node *pd = pvd->pvd_pn;
730 pid_t pid = pvd->pvd_pid;
731 struct proc *p, *proc;
732 struct pfs_node *pn;
733 struct uio *uio;
734 struct pfsentry *pfsent, *pfsent2;
735 struct pfsdirentlist lst;
736 off_t offset;
737 int error, i, resid;
738
739 STAILQ_INIT(&lst);
740 error = 0;
741 KASSERT(pd->pn_info == vn->v_mount->mnt_data,
742 ("%s(): pn_info does not match mountpoint", __func__));
743 PFS_TRACE(("%s pid %lu", pd->pn_name, (unsigned long)pid));
744 pfs_assert_not_owned(pd);
745
746 if (vn->v_type != VDIR)
747 PFS_RETURN (ENOTDIR);
748 KASSERT_PN_IS_DIR(pd);
749 uio = va->a_uio;
750
751 /* only allow reading entire entries */
752 offset = uio->uio_offset;
753 resid = uio->uio_resid;
754 if (offset < 0 || offset % PFS_DELEN != 0 ||
755 (resid && resid < PFS_DELEN))
756 PFS_RETURN (EINVAL);
757 if (resid == 0)
758 PFS_RETURN (0);
759
760 sx_slock(&allproc_lock);
761 pfs_lock(pd);
762
763 /* check if the directory is visible to the caller */
764 if (!pfs_visible(curthread, pd, pid, &proc)) {
765 sx_sunlock(&allproc_lock);
766 pfs_unlock(pd);
767 PFS_RETURN (ENOENT);
768 }
769 KASSERT(pid == NO_PID || proc != NULL,
770 ("%s(): no process for pid %lu", __func__, (unsigned long)pid));
771
772 /* skip unwanted entries */
773 for (pn = NULL, p = NULL; offset > 0; offset -= PFS_DELEN) {
774 if (pfs_iterate(curthread, proc, pd, &pn, &p) == -1) {
775 /* nothing left... */
776 if (proc != NULL)
777 PROC_UNLOCK(proc);
778 pfs_unlock(pd);
779 sx_sunlock(&allproc_lock);
780 PFS_RETURN (0);
781 }
782 }
783
784 /* fill in entries */
785 while (pfs_iterate(curthread, proc, pd, &pn, &p) != -1 &&
786 resid >= PFS_DELEN) {
787 if ((pfsent = malloc(sizeof(struct pfsentry), M_IOV,
788 M_NOWAIT | M_ZERO)) == NULL) {
789 error = ENOMEM;
790 break;
791 }
792 pfsent->entry.d_reclen = PFS_DELEN;
793 pfsent->entry.d_fileno = pn_fileno(pn, pid);
794 /* PFS_DELEN was picked to fit PFS_NAMLEN */
795 for (i = 0; i < PFS_NAMELEN - 1 && pn->pn_name[i] != '\0'; ++i)
796 pfsent->entry.d_name[i] = pn->pn_name[i];
797 pfsent->entry.d_name[i] = 0;
798 pfsent->entry.d_namlen = i;
799 switch (pn->pn_type) {
800 case pfstype_procdir:
801 KASSERT(p != NULL,
802 ("reached procdir node with p == NULL"));
803 pfsent->entry.d_namlen = snprintf(pfsent->entry.d_name,
804 PFS_NAMELEN, "%d", p->p_pid);
805 /* fall through */
806 case pfstype_root:
807 case pfstype_dir:
808 case pfstype_this:
809 case pfstype_parent:
810 pfsent->entry.d_type = DT_DIR;
811 break;
812 case pfstype_file:
813 pfsent->entry.d_type = DT_REG;
814 break;
815 case pfstype_symlink:
816 pfsent->entry.d_type = DT_LNK;
817 break;
818 default:
819 panic("%s has unexpected node type: %d", pn->pn_name, pn->pn_type);
820 }
821 PFS_TRACE(("%s", pfsent->entry.d_name));
822 STAILQ_INSERT_TAIL(&lst, pfsent, link);
823 offset += PFS_DELEN;
824 resid -= PFS_DELEN;
825 }
826 if (proc != NULL)
827 PROC_UNLOCK(proc);
828 pfs_unlock(pd);
829 sx_sunlock(&allproc_lock);
830 i = 0;
831 STAILQ_FOREACH_SAFE(pfsent, &lst, link, pfsent2) {
832 if (error == 0)
833 error = uiomove(&pfsent->entry, PFS_DELEN, uio);
834 free(pfsent, M_IOV);
835 i++;
836 }
837 PFS_TRACE(("%d bytes", i * PFS_DELEN));
838 PFS_RETURN (error);
839 }
840
841 /*
842 * Read a symbolic link
843 */
844 static int
845 pfs_readlink(struct vop_readlink_args *va)
846 {
847 struct vnode *vn = va->a_vp;
848 struct pfs_vdata *pvd = vn->v_data;
849 struct pfs_node *pn = pvd->pvd_pn;
850 struct uio *uio = va->a_uio;
851 struct proc *proc = NULL;
852 char buf[PATH_MAX];
853 struct sbuf sb;
854 int error, locked;
855
856 PFS_TRACE(("%s", pn->pn_name));
857 pfs_assert_not_owned(pn);
858
859 if (vn->v_type != VLNK)
860 PFS_RETURN (EINVAL);
861 KASSERT_PN_IS_LINK(pn);
862
863 if (pn->pn_fill == NULL)
864 PFS_RETURN (EIO);
865
866 if (pvd->pvd_pid != NO_PID) {
867 if ((proc = pfind(pvd->pvd_pid)) == NULL)
868 PFS_RETURN (EIO);
869 if (proc->p_flag & P_WEXIT) {
870 PROC_UNLOCK(proc);
871 PFS_RETURN (EIO);
872 }
873 _PHOLD(proc);
874 PROC_UNLOCK(proc);
875 }
876 vhold(vn);
877 locked = VOP_ISLOCKED(vn);
878 VOP_UNLOCK(vn, 0);
879
880 /* sbuf_new() can't fail with a static buffer */
881 sbuf_new(&sb, buf, sizeof buf, 0);
882
883 error = pn_fill(curthread, proc, pn, &sb, NULL);
884
885 if (proc != NULL)
886 PRELE(proc);
887 vn_lock(vn, locked | LK_RETRY);
888 vdrop(vn);
889
890 if (error) {
891 sbuf_delete(&sb);
892 PFS_RETURN (error);
893 }
894
895 if (sbuf_finish(&sb) != 0) {
896 sbuf_delete(&sb);
897 PFS_RETURN (ENAMETOOLONG);
898 }
899
900 error = uiomove_frombuf(sbuf_data(&sb), sbuf_len(&sb), uio);
901 sbuf_delete(&sb);
902 PFS_RETURN (error);
903 }
904
905 /*
906 * Reclaim a vnode
907 */
908 static int
909 pfs_reclaim(struct vop_reclaim_args *va)
910 {
911 struct vnode *vn = va->a_vp;
912 struct pfs_vdata *pvd = vn->v_data;
913 struct pfs_node *pn = pvd->pvd_pn;
914
915 PFS_TRACE(("%s", pn->pn_name));
916 pfs_assert_not_owned(pn);
917
918 return (pfs_vncache_free(va->a_vp));
919 }
920
921 /*
922 * Set attributes
923 */
924 static int
925 pfs_setattr(struct vop_setattr_args *va)
926 {
927 struct vnode *vn = va->a_vp;
928 struct pfs_vdata *pvd = vn->v_data;
929 struct pfs_node *pn = pvd->pvd_pn;
930
931 PFS_TRACE(("%s", pn->pn_name));
932 pfs_assert_not_owned(pn);
933
934 PFS_RETURN (EOPNOTSUPP);
935 }
936
937 /*
938 * Write to a file
939 */
940 static int
941 pfs_write(struct vop_write_args *va)
942 {
943 struct vnode *vn = va->a_vp;
944 struct pfs_vdata *pvd = vn->v_data;
945 struct pfs_node *pn = pvd->pvd_pn;
946 struct uio *uio = va->a_uio;
947 struct proc *proc;
948 struct sbuf sb;
949 int error;
950
951 PFS_TRACE(("%s", pn->pn_name));
952 pfs_assert_not_owned(pn);
953
954 if (vn->v_type != VREG)
955 PFS_RETURN (EINVAL);
956 KASSERT_PN_IS_FILE(pn);
957
958 if (!(pn->pn_flags & PFS_WR))
959 PFS_RETURN (EBADF);
960
961 if (pn->pn_fill == NULL)
962 PFS_RETURN (EIO);
963
964 /*
965 * This is necessary because either process' privileges may
966 * have changed since the open() call.
967 */
968 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc))
969 PFS_RETURN (EIO);
970 if (proc != NULL) {
971 _PHOLD(proc);
972 PROC_UNLOCK(proc);
973 }
974
975 if (pn->pn_flags & PFS_RAWWR) {
976 error = pn_fill(curthread, proc, pn, NULL, uio);
977 if (proc != NULL)
978 PRELE(proc);
979 PFS_RETURN (error);
980 }
981
982 sbuf_uionew(&sb, uio, &error);
983 if (error) {
984 if (proc != NULL)
985 PRELE(proc);
986 PFS_RETURN (error);
987 }
988
989 error = pn_fill(curthread, proc, pn, &sb, uio);
990
991 sbuf_delete(&sb);
992 if (proc != NULL)
993 PRELE(proc);
994 PFS_RETURN (error);
995 }
996
997 /*
998 * Vnode operations
999 */
1000 struct vop_vector pfs_vnodeops = {
1001 .vop_default = &default_vnodeops,
1002
1003 .vop_access = pfs_access,
1004 .vop_cachedlookup = pfs_lookup,
1005 .vop_close = pfs_close,
1006 .vop_create = VOP_EOPNOTSUPP,
1007 .vop_getattr = pfs_getattr,
1008 .vop_getextattr = pfs_getextattr,
1009 .vop_ioctl = pfs_ioctl,
1010 .vop_link = VOP_EOPNOTSUPP,
1011 .vop_lookup = vfs_cache_lookup,
1012 .vop_mkdir = VOP_EOPNOTSUPP,
1013 .vop_mknod = VOP_EOPNOTSUPP,
1014 .vop_open = pfs_open,
1015 .vop_read = pfs_read,
1016 .vop_readdir = pfs_readdir,
1017 .vop_readlink = pfs_readlink,
1018 .vop_reclaim = pfs_reclaim,
1019 .vop_remove = VOP_EOPNOTSUPP,
1020 .vop_rename = VOP_EOPNOTSUPP,
1021 .vop_rmdir = VOP_EOPNOTSUPP,
1022 .vop_setattr = pfs_setattr,
1023 .vop_symlink = VOP_EOPNOTSUPP,
1024 .vop_vptocnp = pfs_vptocnp,
1025 .vop_write = pfs_write,
1026 /* XXX I've probably forgotten a few that need VOP_EOPNOTSUPP */
1027 };
Cache object: 02c0b9ce609957a2f4e5b1780af614e4
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