xref: /netbsd-src/sys/compat/netbsd32/netbsd32_fs.c (revision 267197ec1eebfcb9810ea27a89625b6ddf68e3e7)
1 /*	$NetBSD: netbsd32_fs.c,v 1.50 2008/01/05 19:14:08 dsl Exp $	*/
2 
3 /*
4  * Copyright (c) 1998, 2001 Matthew R. Green
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
23  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
25  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: netbsd32_fs.c,v 1.50 2008/01/05 19:14:08 dsl Exp $");
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/malloc.h>
37 #include <sys/mount.h>
38 #include <sys/socket.h>
39 #include <sys/socketvar.h>
40 #include <sys/stat.h>
41 #include <sys/time.h>
42 #include <sys/ktrace.h>
43 #include <sys/resourcevar.h>
44 #include <sys/vnode.h>
45 #include <sys/file.h>
46 #include <sys/filedesc.h>
47 #include <sys/namei.h>
48 #include <sys/statvfs.h>
49 #include <sys/syscallargs.h>
50 #include <sys/proc.h>
51 #include <sys/dirent.h>
52 #include <sys/kauth.h>
53 #include <sys/vfs_syscalls.h>
54 
55 #include <compat/netbsd32/netbsd32.h>
56 #include <compat/netbsd32/netbsd32_syscallargs.h>
57 #include <compat/netbsd32/netbsd32_conv.h>
58 #include <compat/sys/mount.h>
59 
60 
61 static int dofilereadv32(struct lwp *, int, struct file *, struct netbsd32_iovec *,
62 			      int, off_t *, int, register_t *);
63 static int dofilewritev32(struct lwp *, int, struct file *, struct netbsd32_iovec *,
64 			       int,  off_t *, int, register_t *);
65 
66 struct iovec *
67 netbsd32_get_iov(struct netbsd32_iovec *iov32, int iovlen, struct iovec *aiov,
68     int aiov_len)
69 {
70 #define N_IOV32 8
71 	struct netbsd32_iovec aiov32[N_IOV32];
72 	struct iovec *iov = aiov;
73 	struct iovec *iovp;
74 	int i, n, j;
75 	int error;
76 
77 	if (iovlen < 0 || iovlen > IOV_MAX)
78 		return NULL;
79 
80 	if (iovlen > aiov_len)
81 		iov = malloc(iovlen * sizeof (*iov), M_TEMP, M_WAITOK);
82 
83 	iovp = iov;
84 	for (i = 0; i < iovlen; iov32 += N_IOV32, i += N_IOV32) {
85 		n = iovlen - i;
86 		if (n > N_IOV32)
87 			n = N_IOV32;
88 		error = copyin(iov32, aiov32, n * sizeof (*iov32));
89 		if (error != 0) {
90 			if (iov != aiov)
91 				free(iov, M_TEMP);
92 			return NULL;
93 		}
94 		for (j = 0; j < n; iovp++, j++) {
95 			iovp->iov_base = NETBSD32PTR64(aiov32[j].iov_base);
96 			iovp->iov_len = aiov32[j].iov_len;
97 		}
98 	}
99 	return iov;
100 #undef N_IOV32
101 }
102 
103 int
104 netbsd32_readv(struct lwp *l, const struct netbsd32_readv_args *uap, register_t *retval)
105 {
106 	/* {
107 		syscallarg(int) fd;
108 		syscallarg(const netbsd32_iovecp_t) iovp;
109 		syscallarg(int) iovcnt;
110 	} */
111 	int fd = SCARG(uap, fd);
112 	struct proc *p = l->l_proc;
113 	struct file *fp;
114 	struct filedesc *fdp = p->p_fd;
115 
116 	if ((fp = fd_getfile(fdp, fd)) == NULL)
117 		return (EBADF);
118 
119 	if ((fp->f_flag & FREAD) == 0) {
120 		FILE_UNLOCK(fp);
121 		return (EBADF);
122 	}
123 
124 	FILE_USE(fp);
125 
126 	return (dofilereadv32(l, fd, fp,
127 	    (struct netbsd32_iovec *)SCARG_P32(uap, iovp),
128 	    SCARG(uap, iovcnt), &fp->f_offset, FOF_UPDATE_OFFSET, retval));
129 }
130 
131 /* Damn thing copies in the iovec! */
132 int
133 dofilereadv32(struct lwp *l, int fd, struct file *fp, struct netbsd32_iovec *iovp, int iovcnt, off_t *offset, int flags, register_t *retval)
134 {
135 	struct uio auio;
136 	struct iovec *iov;
137 	struct iovec *needfree;
138 	struct iovec aiov[UIO_SMALLIOV];
139 	long i, cnt, error = 0;
140 	u_int iovlen;
141 	struct iovec *ktriov = NULL;
142 
143 	/* note: can't use iovlen until iovcnt is validated */
144 	iovlen = iovcnt * sizeof(struct iovec);
145 	if ((u_int)iovcnt > UIO_SMALLIOV) {
146 		if ((u_int)iovcnt > IOV_MAX) {
147 			error = EINVAL;
148 			goto out;
149 		}
150 		iov = malloc(iovlen, M_IOV, M_WAITOK);
151 		needfree = iov;
152 	} else if ((u_int)iovcnt > 0) {
153 		iov = aiov;
154 		needfree = NULL;
155 	} else {
156 		error = EINVAL;
157 		goto out;
158 	}
159 
160 	auio.uio_iov = iov;
161 	auio.uio_iovcnt = iovcnt;
162 	auio.uio_rw = UIO_READ;
163 	auio.uio_vmspace = l->l_proc->p_vmspace;
164 	error = netbsd32_to_iovecin(iovp, iov, iovcnt);
165 	if (error)
166 		goto done;
167 	auio.uio_resid = 0;
168 	for (i = 0; i < iovcnt; i++) {
169 		auio.uio_resid += iov->iov_len;
170 		/*
171 		 * Reads return ssize_t because -1 is returned on error.
172 		 * Therefore we must restrict the length to SSIZE_MAX to
173 		 * avoid garbage return values.
174 		 */
175 		if (iov->iov_len > SSIZE_MAX || auio.uio_resid > SSIZE_MAX) {
176 			error = EINVAL;
177 			goto done;
178 		}
179 		iov++;
180 	}
181 
182 	/*
183 	 * if tracing, save a copy of iovec
184 	 */
185 	if (ktrpoint(KTR_GENIO)) {
186 		ktriov = malloc(iovlen, M_TEMP, M_WAITOK);
187 		memcpy((void *)ktriov, (void *)auio.uio_iov, iovlen);
188 	}
189 
190 	cnt = auio.uio_resid;
191 	error = (*fp->f_ops->fo_read)(fp, offset, &auio, fp->f_cred, flags);
192 	if (error)
193 		if (auio.uio_resid != cnt && (error == ERESTART ||
194 		    error == EINTR || error == EWOULDBLOCK))
195 			error = 0;
196 	cnt -= auio.uio_resid;
197 
198 	if (ktriov != NULL) {
199 		ktrgeniov(fd, UIO_READ, ktriov, cnt, error);
200 		free(ktriov, M_TEMP);
201 	}
202 
203 	*retval = cnt;
204 done:
205 	if (needfree)
206 		free(needfree, M_IOV);
207 out:
208 	FILE_UNUSE(fp, l);
209 	return (error);
210 }
211 
212 int
213 netbsd32_writev(struct lwp *l, const struct netbsd32_writev_args *uap, register_t *retval)
214 {
215 	/* {
216 		syscallarg(int) fd;
217 		syscallarg(const netbsd32_iovecp_t) iovp;
218 		syscallarg(int) iovcnt;
219 	} */
220 	int fd = SCARG(uap, fd);
221 	struct file *fp;
222 	struct proc *p = l->l_proc;
223 	struct filedesc *fdp = p->p_fd;
224 
225 	if ((fp = fd_getfile(fdp, fd)) == NULL)
226 		return (EBADF);
227 
228 	if ((fp->f_flag & FWRITE) == 0) {
229 		FILE_UNLOCK(fp);
230 		return (EBADF);
231 	}
232 
233 	FILE_USE(fp);
234 
235 	return (dofilewritev32(l, fd, fp,
236 	    (struct netbsd32_iovec *)SCARG_P32(uap, iovp),
237 	    SCARG(uap, iovcnt), &fp->f_offset, FOF_UPDATE_OFFSET, retval));
238 }
239 
240 int
241 dofilewritev32(struct lwp *l, int fd, struct file *fp, struct netbsd32_iovec *iovp, int iovcnt, off_t *offset, int flags, register_t *retval)
242 {
243 	struct uio auio;
244 	struct iovec *iov;
245 	struct iovec *needfree;
246 	struct iovec aiov[UIO_SMALLIOV];
247 	struct proc *p = l->l_proc;
248 	long i, cnt, error = 0;
249 	u_int iovlen;
250 	struct iovec *ktriov = NULL;
251 
252 	/* note: can't use iovlen until iovcnt is validated */
253 	iovlen = iovcnt * sizeof(struct iovec);
254 	if ((u_int)iovcnt > UIO_SMALLIOV) {
255 		if ((u_int)iovcnt > IOV_MAX) {
256 			error = EINVAL;
257 			goto out;
258 		}
259 		iov = malloc(iovlen, M_IOV, M_WAITOK);
260 		needfree = iov;
261 	} else if ((u_int)iovcnt > 0) {
262 		iov = aiov;
263 		needfree = NULL;
264 	} else {
265 		error = EINVAL;
266 		goto out;
267 	}
268 
269 	auio.uio_iov = iov;
270 	auio.uio_iovcnt = iovcnt;
271 	auio.uio_rw = UIO_WRITE;
272 	auio.uio_vmspace = l->l_proc->p_vmspace;
273 	error = netbsd32_to_iovecin(iovp, iov, iovcnt);
274 	if (error)
275 		goto done;
276 	auio.uio_resid = 0;
277 	for (i = 0; i < iovcnt; i++) {
278 		auio.uio_resid += iov->iov_len;
279 		/*
280 		 * Writes return ssize_t because -1 is returned on error.
281 		 * Therefore we must restrict the length to SSIZE_MAX to
282 		 * avoid garbage return values.
283 		 */
284 		if (iov->iov_len > SSIZE_MAX || auio.uio_resid > SSIZE_MAX) {
285 			error = EINVAL;
286 			goto done;
287 		}
288 		iov++;
289 	}
290 
291 	/*
292 	 * if tracing, save a copy of iovec
293 	 */
294 	if (ktrpoint(KTR_GENIO))  {
295 		ktriov = malloc(iovlen, M_TEMP, M_WAITOK);
296 		memcpy((void *)ktriov, (void *)auio.uio_iov, iovlen);
297 	}
298 
299 	cnt = auio.uio_resid;
300 	error = (*fp->f_ops->fo_write)(fp, offset, &auio, fp->f_cred, flags);
301 	if (error) {
302 		if (auio.uio_resid != cnt && (error == ERESTART ||
303 		    error == EINTR || error == EWOULDBLOCK))
304 			error = 0;
305 		if (error == EPIPE) {
306 			mutex_enter(&proclist_mutex);
307 			psignal(p, SIGPIPE);
308 			mutex_exit(&proclist_mutex);
309 		}
310 	}
311 	cnt -= auio.uio_resid;
312 	if (ktriov != NULL) {
313 		ktrgenio(fd, UIO_WRITE, ktriov, cnt, error);
314 		free(ktriov, M_TEMP);
315 	}
316 	*retval = cnt;
317 done:
318 	if (needfree)
319 		free(needfree, M_IOV);
320 out:
321 	FILE_UNUSE(fp, l);
322 	return (error);
323 }
324 
325 /*
326  * Common routine to set access and modification times given a vnode.
327  */
328 static int
329 get_utimes32(const netbsd32_timevalp_t *tptr, struct timeval *tv,
330     struct timeval **tvp)
331 {
332 	int error;
333 	struct netbsd32_timeval tv32[2];
334 
335 	if (tptr == NULL) {
336 		*tvp = NULL;
337 		return 0;
338 	}
339 
340 	error = copyin(tptr, tv32, sizeof(tv32));
341 	if (error)
342 		return error;
343 	netbsd32_to_timeval(&tv32[0], &tv[0]);
344 	netbsd32_to_timeval(&tv32[1], &tv[1]);
345 
346 	*tvp = tv;
347 	return 0;
348 }
349 
350 int
351 netbsd32_utimes(struct lwp *l, const struct netbsd32_utimes_args *uap, register_t *retval)
352 {
353 	/* {
354 		syscallarg(const netbsd32_charp) path;
355 		syscallarg(const netbsd32_timevalp_t) tptr;
356 	} */
357 	int error;
358 	struct timeval tv[2], *tvp;
359 
360 	error = get_utimes32(SCARG_P32(uap, tptr), tv, &tvp);
361 	if (error != 0)
362 		return error;
363 
364 	return do_sys_utimes(l, NULL, SCARG_P32(uap, path), FOLLOW,
365 			    tvp, UIO_SYSSPACE);
366 }
367 
368 static int
369 netbds32_copyout_statvfs(const void *kp, void *up, size_t len)
370 {
371 	struct netbsd32_statvfs *sbuf_32;
372 	int error;
373 
374 	sbuf_32 = malloc(sizeof *sbuf_32, M_TEMP, M_WAITOK);
375 	netbsd32_from_statvfs(kp, sbuf_32);
376 	error = copyout(sbuf_32, up, sizeof(*sbuf_32));
377 	free(sbuf_32, M_TEMP);
378 
379 	return error;
380 }
381 
382 int
383 netbsd32_statvfs1(struct lwp *l, const struct netbsd32_statvfs1_args *uap, register_t *retval)
384 {
385 	/* {
386 		syscallarg(const netbsd32_charp) path;
387 		syscallarg(netbsd32_statvfsp_t) buf;
388 		syscallarg(int) flags;
389 	} */
390 	struct statvfs *sb;
391 	int error;
392 
393 	sb = STATVFSBUF_GET();
394 	error = do_sys_pstatvfs(l, SCARG_P32(uap, path), SCARG(uap, flags), sb);
395 	if (error == 0)
396 		error = netbds32_copyout_statvfs(sb, SCARG_P32(uap, buf), 0);
397 	STATVFSBUF_PUT(sb);
398 	return error;
399 }
400 
401 int
402 netbsd32_fstatvfs1(struct lwp *l, const struct netbsd32_fstatvfs1_args *uap, register_t *retval)
403 {
404 	/* {
405 		syscallarg(int) fd;
406 		syscallarg(netbsd32_statvfsp_t) buf;
407 		syscallarg(int) flags;
408 	} */
409 	struct statvfs *sb;
410 	int error;
411 
412 	sb = STATVFSBUF_GET();
413 	error = do_sys_fstatvfs(l, SCARG(uap, fd), SCARG(uap, flags), sb);
414 	if (error == 0)
415 		error = netbds32_copyout_statvfs(sb, SCARG_P32(uap, buf), 0);
416 	STATVFSBUF_PUT(sb);
417 	return error;
418 }
419 
420 int
421 netbsd32_getvfsstat(struct lwp *l, const struct netbsd32_getvfsstat_args *uap, register_t *retval)
422 {
423 	/* {
424 		syscallarg(netbsd32_statvfsp_t) buf;
425 		syscallarg(netbsd32_size_t) bufsize;
426 		syscallarg(int) flags;
427 	} */
428 
429 	return do_sys_getvfsstat(l, SCARG_P32(uap, buf), SCARG(uap, bufsize),
430 	    SCARG(uap, flags), netbds32_copyout_statvfs,
431 	    sizeof (struct netbsd32_statvfs), retval);
432 }
433 
434 int
435 netbsd32___fhstatvfs140(struct lwp *l, const struct netbsd32___fhstatvfs140_args *uap, register_t *retval)
436 {
437 	/* {
438 		syscallarg(const netbsd32_pointer_t) fhp;
439 		syscallarg(netbsd32_size_t) fh_size;
440 		syscallarg(netbsd32_statvfsp_t) buf;
441 		syscallarg(int) flags;
442 	} */
443 	struct statvfs *sb;
444 	int error;
445 
446 	sb = STATVFSBUF_GET();
447 	error = do_fhstatvfs(l, SCARG_P32(uap, fhp), SCARG(uap, fh_size), sb,
448 	    SCARG(uap, flags));
449 
450 	if (error == 0)
451 		error = netbds32_copyout_statvfs(sb, SCARG_P32(uap, buf), 0);
452 	STATVFSBUF_PUT(sb);
453 
454 	return error;
455 }
456 
457 int
458 netbsd32_futimes(struct lwp *l, const struct netbsd32_futimes_args *uap, register_t *retval)
459 {
460 	/* {
461 		syscallarg(int) fd;
462 		syscallarg(const netbsd32_timevalp_t) tptr;
463 	} */
464 	int error;
465 	struct file *fp;
466 	struct timeval tv[2], *tvp;
467 
468 	error = get_utimes32(SCARG_P32(uap, tptr), tv, &tvp);
469 	if (error != 0)
470 		return error;
471 
472 	/* getvnode() will use the descriptor for us */
473 	if ((error = getvnode(l->l_proc->p_fd, SCARG(uap, fd), &fp)) != 0)
474 		return (error);
475 
476 	error = do_sys_utimes(l, fp->f_data, NULL, 0, tvp, UIO_SYSSPACE);
477 
478 	FILE_UNUSE(fp, l);
479 	return (error);
480 }
481 
482 int
483 netbsd32_sys___getdents30(struct lwp *l, const struct netbsd32_sys___getdents30_args *uap, register_t *retval)
484 {
485 	/* {
486 		syscallarg(int) fd;
487 		syscallarg(netbsd32_charp) buf;
488 		syscallarg(netbsd32_size_t) count;
489 	} */
490 	struct file *fp;
491 	int error, done;
492 	struct proc *p = l->l_proc;
493 
494 	/* getvnode() will use the descriptor for us */
495 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
496 		return (error);
497 	if ((fp->f_flag & FREAD) == 0) {
498 		error = EBADF;
499 		goto out;
500 	}
501 	error = vn_readdir(fp, SCARG_P32(uap, buf),
502 	    UIO_USERSPACE, SCARG(uap, count), &done, l, 0, 0);
503 	*retval = done;
504  out:
505 	FILE_UNUSE(fp, l);
506 	return (error);
507 }
508 
509 int
510 netbsd32_lutimes(struct lwp *l, const struct netbsd32_lutimes_args *uap, register_t *retval)
511 {
512 	/* {
513 		syscallarg(const netbsd32_charp) path;
514 		syscallarg(const netbsd32_timevalp_t) tptr;
515 	} */
516 	int error;
517 	struct timeval tv[2], *tvp;
518 
519 	error = get_utimes32(SCARG_P32(uap, tptr), tv, &tvp);
520 	if (error != 0)
521 		return error;
522 
523 	return do_sys_utimes(l, NULL, SCARG_P32(uap, path), NOFOLLOW,
524 			    tvp, UIO_SYSSPACE);
525 }
526 
527 int
528 netbsd32_sys___stat30(struct lwp *l, const struct netbsd32_sys___stat30_args *uap, register_t *retval)
529 {
530 	/* {
531 		syscallarg(const netbsd32_charp) path;
532 		syscallarg(netbsd32_statp_t) ub;
533 	} */
534 	struct netbsd32_stat sb32;
535 	struct stat sb;
536 	int error;
537 	const char *path;
538 
539 	path = SCARG_P32(uap, path);
540 
541 	error = do_sys_stat(l, path, FOLLOW, &sb);
542 	if (error)
543 		return (error);
544 	netbsd32_from___stat30(&sb, &sb32);
545 	error = copyout(&sb32, SCARG_P32(uap, ub), sizeof(sb32));
546 	return (error);
547 }
548 
549 int
550 netbsd32_sys___fstat30(struct lwp *l, const struct netbsd32_sys___fstat30_args *uap, register_t *retval)
551 {
552 	/* {
553 		syscallarg(int) fd;
554 		syscallarg(netbsd32_statp_t) sb;
555 	} */
556 	int fd = SCARG(uap, fd);
557 	struct proc *p = l->l_proc;
558 	struct filedesc *fdp = p->p_fd;
559 	struct file *fp;
560 	struct netbsd32_stat sb32;
561 	struct stat ub;
562 	int error = 0;
563 
564 	if ((fp = fd_getfile(fdp, fd)) == NULL)
565 		return (EBADF);
566 
567 	FILE_USE(fp);
568 	error = (*fp->f_ops->fo_stat)(fp, &ub, l);
569 	FILE_UNUSE(fp, l);
570 
571 	if (error == 0) {
572 		netbsd32_from___stat30(&ub, &sb32);
573 		error = copyout(&sb32, SCARG_P32(uap, sb), sizeof(sb32));
574 	}
575 	return (error);
576 }
577 
578 int
579 netbsd32_sys___lstat30(struct lwp *l, const struct netbsd32_sys___lstat30_args *uap, register_t *retval)
580 {
581 	/* {
582 		syscallarg(const netbsd32_charp) path;
583 		syscallarg(netbsd32_statp_t) ub;
584 	} */
585 	struct netbsd32_stat sb32;
586 	struct stat sb;
587 	int error;
588 	const char *path;
589 
590 	path = SCARG_P32(uap, path);
591 
592 	error = do_sys_stat(l, path, NOFOLLOW, &sb);
593 	if (error)
594 		return (error);
595 	netbsd32_from___stat30(&sb, &sb32);
596 	error = copyout(&sb32, SCARG_P32(uap, ub), sizeof(sb32));
597 	return (error);
598 }
599 
600 int
601 netbsd32___fhstat40(struct lwp *l, const struct netbsd32___fhstat40_args *uap, register_t *retval)
602 {
603 	/* {
604 		syscallarg(const netbsd32_pointer_t) fhp;
605 		syscallarg(netbsd32_size_t) fh_size;
606 		syscallarg(netbsd32_statp_t) sb;
607 	} */
608 	struct stat sb;
609 	struct netbsd32_stat sb32;
610 	int error;
611 
612 	error = do_fhstat(l, SCARG_P32(uap, fhp), SCARG(uap, fh_size), &sb);
613 	if (error != 0) {
614 		netbsd32_from___stat30(&sb, &sb32);
615 		error = copyout(&sb32, SCARG_P32(uap, sb), sizeof(sb));
616 	}
617 	return error;
618 }
619 
620 int
621 netbsd32_preadv(struct lwp *l, const struct netbsd32_preadv_args *uap, register_t *retval)
622 {
623 	/* {
624 		syscallarg(int) fd;
625 		syscallarg(const netbsd32_iovecp_t) iovp;
626 		syscallarg(int) iovcnt;
627 		syscallarg(int) pad;
628 		syscallarg(off_t) offset;
629 	} */
630 	struct proc *p = l->l_proc;
631 	struct filedesc *fdp = p->p_fd;
632 	struct file *fp;
633 	struct vnode *vp;
634 	off_t offset;
635 	int error, fd = SCARG(uap, fd);
636 
637 	if ((fp = fd_getfile(fdp, fd)) == NULL)
638 		return (EBADF);
639 
640 	if ((fp->f_flag & FREAD) == 0) {
641 		FILE_UNLOCK(fp);
642 		return (EBADF);
643 	}
644 
645 	FILE_USE(fp);
646 
647 	vp = (struct vnode *)fp->f_data;
648 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO) {
649 		error = ESPIPE;
650 		goto out;
651 	}
652 
653 	offset = SCARG(uap, offset);
654 
655 	/*
656 	 * XXX This works because no file systems actually
657 	 * XXX take any action on the seek operation.
658 	 */
659 	if ((error = VOP_SEEK(vp, fp->f_offset, offset, fp->f_cred)) != 0)
660 		goto out;
661 
662 	return (dofilereadv32(l, fd, fp, SCARG_P32(uap, iovp),
663 	    SCARG(uap, iovcnt), &offset, 0, retval));
664 
665 out:
666 	FILE_UNUSE(fp, l);
667 	return (error);
668 }
669 
670 int
671 netbsd32_pwritev(struct lwp *l, const struct netbsd32_pwritev_args *uap, register_t *retval)
672 {
673 	/* {
674 		syscallarg(int) fd;
675 		syscallarg(const netbsd32_iovecp_t) iovp;
676 		syscallarg(int) iovcnt;
677 		syscallarg(int) pad;
678 		syscallarg(off_t) offset;
679 	} */
680 	struct proc *p = l->l_proc;
681 	struct filedesc *fdp = p->p_fd;
682 	struct file *fp;
683 	struct vnode *vp;
684 	off_t offset;
685 	int error, fd = SCARG(uap, fd);
686 
687 	if ((fp = fd_getfile(fdp, fd)) == NULL)
688 		return (EBADF);
689 
690 	if ((fp->f_flag & FWRITE) == 0) {
691 		FILE_UNLOCK(fp);
692 		return (EBADF);
693 	}
694 
695 	FILE_USE(fp);
696 
697 	vp = (struct vnode *)fp->f_data;
698 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO) {
699 		error = ESPIPE;
700 		goto out;
701 	}
702 
703 	offset = SCARG(uap, offset);
704 
705 	/*
706 	 * XXX This works because no file systems actually
707 	 * XXX take any action on the seek operation.
708 	 */
709 	if ((error = VOP_SEEK(vp, fp->f_offset, offset, fp->f_cred)) != 0)
710 		goto out;
711 
712 	return (dofilewritev32(l, fd, fp, SCARG_P32(uap, iovp),
713 	    SCARG(uap, iovcnt), &offset, 0, retval));
714 
715 out:
716 	FILE_UNUSE(fp, l);
717 	return (error);
718 }
719 
720 /*
721  * Find pathname of process's current directory.
722  *
723  * Use vfs vnode-to-name reverse cache; if that fails, fall back
724  * to reading directory contents.
725  */
726 /* XXX NH Why does this exist */
727 int
728 getcwd_common(struct vnode *, struct vnode *,
729 		   char **, char *, int, int, struct lwp *);
730 
731 int
732 netbsd32___getcwd(struct lwp *l, const struct netbsd32___getcwd_args *uap, register_t *retval)
733 {
734 	/* {
735 		syscallarg(char *) bufp;
736 		syscallarg(size_t) length;
737 	} */
738 	struct proc *p = l->l_proc;
739 	int     error;
740 	char   *path;
741 	char   *bp, *bend;
742 	int     len = (int)SCARG(uap, length);
743 	int	lenused;
744 
745 	if (len > MAXPATHLEN*4)
746 		len = MAXPATHLEN*4;
747 	else if (len < 2)
748 		return ERANGE;
749 
750 	path = (char *)malloc(len, M_TEMP, M_WAITOK);
751 	if (!path)
752 		return ENOMEM;
753 
754 	bp = &path[len];
755 	bend = bp;
756 	*(--bp) = '\0';
757 
758 	/*
759 	 * 5th argument here is "max number of vnodes to traverse".
760 	 * Since each entry takes up at least 2 bytes in the output buffer,
761 	 * limit it to N/2 vnodes for an N byte buffer.
762 	 */
763 #define GETCWD_CHECK_ACCESS 0x0001
764 	error = getcwd_common (p->p_cwdi->cwdi_cdir, NULL, &bp, path, len/2,
765 			       GETCWD_CHECK_ACCESS, l);
766 
767 	if (error)
768 		goto out;
769 	lenused = bend - bp;
770 	*retval = lenused;
771 	/* put the result into user buffer */
772 	error = copyout(bp, SCARG_P32(uap, bufp), lenused);
773 
774 out:
775 	free(path, M_TEMP);
776 	return error;
777 }
778