xref: /netbsd-src/sys/compat/netbsd32/netbsd32_fs.c (revision 6dffe8d42bd46273f674d7ab834e7be9b1af990e)
1 /*	$NetBSD: netbsd32_fs.c,v 1.57 2009/01/26 13:00:05 njoly 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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: netbsd32_fs.c,v 1.57 2009/01/26 13:00:05 njoly Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/malloc.h>
35 #include <sys/mount.h>
36 #include <sys/socket.h>
37 #include <sys/socketvar.h>
38 #include <sys/stat.h>
39 #include <sys/time.h>
40 #include <sys/ktrace.h>
41 #include <sys/resourcevar.h>
42 #include <sys/vnode.h>
43 #include <sys/file.h>
44 #include <sys/filedesc.h>
45 #include <sys/namei.h>
46 #include <sys/statvfs.h>
47 #include <sys/syscallargs.h>
48 #include <sys/proc.h>
49 #include <sys/dirent.h>
50 #include <sys/kauth.h>
51 #include <sys/vfs_syscalls.h>
52 
53 #include <compat/netbsd32/netbsd32.h>
54 #include <compat/netbsd32/netbsd32_syscallargs.h>
55 #include <compat/netbsd32/netbsd32_conv.h>
56 #include <compat/sys/mount.h>
57 
58 
59 static int dofilereadv32(int, struct file *, struct netbsd32_iovec *,
60 			      int, off_t *, int, register_t *);
61 static int dofilewritev32(int, struct file *, struct netbsd32_iovec *,
62 			       int,  off_t *, int, register_t *);
63 
64 struct iovec *
65 netbsd32_get_iov(struct netbsd32_iovec *iov32, int iovlen, struct iovec *aiov,
66     int aiov_len)
67 {
68 #define N_IOV32 8
69 	struct netbsd32_iovec aiov32[N_IOV32];
70 	struct iovec *iov = aiov;
71 	struct iovec *iovp;
72 	int i, n, j;
73 	int error;
74 
75 	if (iovlen < 0 || iovlen > IOV_MAX)
76 		return NULL;
77 
78 	if (iovlen > aiov_len)
79 		iov = malloc(iovlen * sizeof (*iov), M_TEMP, M_WAITOK);
80 
81 	iovp = iov;
82 	for (i = 0; i < iovlen; iov32 += N_IOV32, i += N_IOV32) {
83 		n = iovlen - i;
84 		if (n > N_IOV32)
85 			n = N_IOV32;
86 		error = copyin(iov32, aiov32, n * sizeof (*iov32));
87 		if (error != 0) {
88 			if (iov != aiov)
89 				free(iov, M_TEMP);
90 			return NULL;
91 		}
92 		for (j = 0; j < n; iovp++, j++) {
93 			iovp->iov_base = NETBSD32PTR64(aiov32[j].iov_base);
94 			iovp->iov_len = aiov32[j].iov_len;
95 		}
96 	}
97 	return iov;
98 #undef N_IOV32
99 }
100 
101 int
102 netbsd32_readv(struct lwp *l, const struct netbsd32_readv_args *uap, register_t *retval)
103 {
104 	/* {
105 		syscallarg(int) fd;
106 		syscallarg(const netbsd32_iovecp_t) iovp;
107 		syscallarg(int) iovcnt;
108 	} */
109 	int fd = SCARG(uap, fd);
110 	file_t *fp;
111 
112 	if ((fp = fd_getfile(fd)) == NULL)
113 		return (EBADF);
114 
115 	if ((fp->f_flag & FREAD) == 0) {
116 		fd_putfile(fd);
117 		return (EBADF);
118 	}
119 
120 	return (dofilereadv32(fd, fp,
121 	    (struct netbsd32_iovec *)SCARG_P32(uap, iovp),
122 	    SCARG(uap, iovcnt), &fp->f_offset, FOF_UPDATE_OFFSET, retval));
123 }
124 
125 /* Damn thing copies in the iovec! */
126 int
127 dofilereadv32(int fd, struct file *fp, struct netbsd32_iovec *iovp, int iovcnt, off_t *offset, int flags, register_t *retval)
128 {
129 	struct uio auio;
130 	struct iovec *iov;
131 	struct iovec *needfree;
132 	struct iovec aiov[UIO_SMALLIOV];
133 	long i, cnt, error = 0;
134 	u_int iovlen;
135 	struct iovec *ktriov = NULL;
136 
137 	/* note: can't use iovlen until iovcnt is validated */
138 	iovlen = iovcnt * sizeof(struct iovec);
139 	if ((u_int)iovcnt > UIO_SMALLIOV) {
140 		if ((u_int)iovcnt > IOV_MAX) {
141 			error = EINVAL;
142 			goto out;
143 		}
144 		iov = malloc(iovlen, M_IOV, M_WAITOK);
145 		needfree = iov;
146 	} else if ((u_int)iovcnt > 0) {
147 		iov = aiov;
148 		needfree = NULL;
149 	} else {
150 		error = EINVAL;
151 		goto out;
152 	}
153 
154 	auio.uio_iov = iov;
155 	auio.uio_iovcnt = iovcnt;
156 	auio.uio_rw = UIO_READ;
157 	auio.uio_vmspace = curproc->p_vmspace;
158 	error = netbsd32_to_iovecin(iovp, iov, iovcnt);
159 	if (error)
160 		goto done;
161 	auio.uio_resid = 0;
162 	for (i = 0; i < iovcnt; i++) {
163 		auio.uio_resid += iov->iov_len;
164 		/*
165 		 * Reads return ssize_t because -1 is returned on error.
166 		 * Therefore we must restrict the length to SSIZE_MAX to
167 		 * avoid garbage return values.
168 		 */
169 		if (iov->iov_len > SSIZE_MAX || auio.uio_resid > SSIZE_MAX) {
170 			error = EINVAL;
171 			goto done;
172 		}
173 		iov++;
174 	}
175 
176 	/*
177 	 * if tracing, save a copy of iovec
178 	 */
179 	if (ktrpoint(KTR_GENIO)) {
180 		ktriov = malloc(iovlen, M_TEMP, M_WAITOK);
181 		memcpy((void *)ktriov, (void *)auio.uio_iov, iovlen);
182 	}
183 
184 	cnt = auio.uio_resid;
185 	error = (*fp->f_ops->fo_read)(fp, offset, &auio, fp->f_cred, flags);
186 	if (error)
187 		if (auio.uio_resid != cnt && (error == ERESTART ||
188 		    error == EINTR || error == EWOULDBLOCK))
189 			error = 0;
190 	cnt -= auio.uio_resid;
191 
192 	if (ktriov != NULL) {
193 		ktrgeniov(fd, UIO_READ, ktriov, cnt, error);
194 		free(ktriov, M_TEMP);
195 	}
196 
197 	*retval = cnt;
198 done:
199 	if (needfree)
200 		free(needfree, M_IOV);
201 out:
202 	fd_putfile(fd);
203 	return (error);
204 }
205 
206 int
207 netbsd32_writev(struct lwp *l, const struct netbsd32_writev_args *uap, register_t *retval)
208 {
209 	/* {
210 		syscallarg(int) fd;
211 		syscallarg(const netbsd32_iovecp_t) iovp;
212 		syscallarg(int) iovcnt;
213 	} */
214 	int fd = SCARG(uap, fd);
215 	file_t *fp;
216 
217 	if ((fp = fd_getfile(fd)) == NULL)
218 		return (EBADF);
219 
220 	if ((fp->f_flag & FWRITE) == 0) {
221 		fd_putfile(fd);
222 		return (EBADF);
223 	}
224 
225 	return (dofilewritev32(fd, fp,
226 	    (struct netbsd32_iovec *)SCARG_P32(uap, iovp),
227 	    SCARG(uap, iovcnt), &fp->f_offset, FOF_UPDATE_OFFSET, retval));
228 }
229 
230 int
231 dofilewritev32(int fd, struct file *fp, struct netbsd32_iovec *iovp, int iovcnt, off_t *offset, int flags, register_t *retval)
232 {
233 	struct uio auio;
234 	struct iovec *iov;
235 	struct iovec *needfree;
236 	struct iovec aiov[UIO_SMALLIOV];
237 	long i, cnt, error = 0;
238 	u_int iovlen;
239 	struct iovec *ktriov = NULL;
240 
241 	/* note: can't use iovlen until iovcnt is validated */
242 	iovlen = iovcnt * sizeof(struct iovec);
243 	if ((u_int)iovcnt > UIO_SMALLIOV) {
244 		if ((u_int)iovcnt > IOV_MAX) {
245 			error = EINVAL;
246 			goto out;
247 		}
248 		iov = malloc(iovlen, M_IOV, M_WAITOK);
249 		needfree = iov;
250 	} else if ((u_int)iovcnt > 0) {
251 		iov = aiov;
252 		needfree = NULL;
253 	} else {
254 		error = EINVAL;
255 		goto out;
256 	}
257 
258 	auio.uio_iov = iov;
259 	auio.uio_iovcnt = iovcnt;
260 	auio.uio_rw = UIO_WRITE;
261 	auio.uio_vmspace = curproc->p_vmspace;
262 	error = netbsd32_to_iovecin(iovp, iov, iovcnt);
263 	if (error)
264 		goto done;
265 	auio.uio_resid = 0;
266 	for (i = 0; i < iovcnt; i++) {
267 		auio.uio_resid += iov->iov_len;
268 		/*
269 		 * Writes return ssize_t because -1 is returned on error.
270 		 * Therefore we must restrict the length to SSIZE_MAX to
271 		 * avoid garbage return values.
272 		 */
273 		if (iov->iov_len > SSIZE_MAX || auio.uio_resid > SSIZE_MAX) {
274 			error = EINVAL;
275 			goto done;
276 		}
277 		iov++;
278 	}
279 
280 	/*
281 	 * if tracing, save a copy of iovec
282 	 */
283 	if (ktrpoint(KTR_GENIO))  {
284 		ktriov = malloc(iovlen, M_TEMP, M_WAITOK);
285 		memcpy((void *)ktriov, (void *)auio.uio_iov, iovlen);
286 	}
287 
288 	cnt = auio.uio_resid;
289 	error = (*fp->f_ops->fo_write)(fp, offset, &auio, fp->f_cred, flags);
290 	if (error) {
291 		if (auio.uio_resid != cnt && (error == ERESTART ||
292 		    error == EINTR || error == EWOULDBLOCK))
293 			error = 0;
294 		if (error == EPIPE) {
295 			mutex_enter(proc_lock);
296 			psignal(curproc, SIGPIPE);
297 			mutex_exit(proc_lock);
298 		}
299 	}
300 	cnt -= auio.uio_resid;
301 	if (ktriov != NULL) {
302 		ktrgenio(fd, UIO_WRITE, ktriov, cnt, error);
303 		free(ktriov, M_TEMP);
304 	}
305 	*retval = cnt;
306 done:
307 	if (needfree)
308 		free(needfree, M_IOV);
309 out:
310 	fd_putfile(fd);
311 	return (error);
312 }
313 
314 /*
315  * Common routine to set access and modification times given a vnode.
316  */
317 static int
318 get_utimes32(const netbsd32_timevalp_t *tptr, struct timeval *tv,
319     struct timeval **tvp)
320 {
321 	int error;
322 	struct netbsd32_timeval tv32[2];
323 
324 	if (tptr == NULL) {
325 		*tvp = NULL;
326 		return 0;
327 	}
328 
329 	error = copyin(tptr, tv32, sizeof(tv32));
330 	if (error)
331 		return error;
332 	netbsd32_to_timeval(&tv32[0], &tv[0]);
333 	netbsd32_to_timeval(&tv32[1], &tv[1]);
334 
335 	*tvp = tv;
336 	return 0;
337 }
338 
339 int
340 netbsd32___utimes50(struct lwp *l, const struct netbsd32___utimes50_args *uap, register_t *retval)
341 {
342 	/* {
343 		syscallarg(const netbsd32_charp) path;
344 		syscallarg(const netbsd32_timevalp_t) tptr;
345 	} */
346 	int error;
347 	struct timeval tv[2], *tvp;
348 
349 	error = get_utimes32(SCARG_P32(uap, tptr), tv, &tvp);
350 	if (error != 0)
351 		return error;
352 
353 	return do_sys_utimes(l, NULL, SCARG_P32(uap, path), FOLLOW,
354 			    tvp, UIO_SYSSPACE);
355 }
356 
357 static int
358 netbds32_copyout_statvfs(const void *kp, void *up, size_t len)
359 {
360 	struct netbsd32_statvfs *sbuf_32;
361 	int error;
362 
363 	sbuf_32 = malloc(sizeof *sbuf_32, M_TEMP, M_WAITOK);
364 	netbsd32_from_statvfs(kp, sbuf_32);
365 	error = copyout(sbuf_32, up, sizeof(*sbuf_32));
366 	free(sbuf_32, M_TEMP);
367 
368 	return error;
369 }
370 
371 int
372 netbsd32_statvfs1(struct lwp *l, const struct netbsd32_statvfs1_args *uap, register_t *retval)
373 {
374 	/* {
375 		syscallarg(const netbsd32_charp) path;
376 		syscallarg(netbsd32_statvfsp_t) buf;
377 		syscallarg(int) flags;
378 	} */
379 	struct statvfs *sb;
380 	int error;
381 
382 	sb = STATVFSBUF_GET();
383 	error = do_sys_pstatvfs(l, SCARG_P32(uap, path), SCARG(uap, flags), sb);
384 	if (error == 0)
385 		error = netbds32_copyout_statvfs(sb, SCARG_P32(uap, buf), 0);
386 	STATVFSBUF_PUT(sb);
387 	return error;
388 }
389 
390 int
391 netbsd32_fstatvfs1(struct lwp *l, const struct netbsd32_fstatvfs1_args *uap, register_t *retval)
392 {
393 	/* {
394 		syscallarg(int) fd;
395 		syscallarg(netbsd32_statvfsp_t) buf;
396 		syscallarg(int) flags;
397 	} */
398 	struct statvfs *sb;
399 	int error;
400 
401 	sb = STATVFSBUF_GET();
402 	error = do_sys_fstatvfs(l, SCARG(uap, fd), SCARG(uap, flags), sb);
403 	if (error == 0)
404 		error = netbds32_copyout_statvfs(sb, SCARG_P32(uap, buf), 0);
405 	STATVFSBUF_PUT(sb);
406 	return error;
407 }
408 
409 int
410 netbsd32_getvfsstat(struct lwp *l, const struct netbsd32_getvfsstat_args *uap, register_t *retval)
411 {
412 	/* {
413 		syscallarg(netbsd32_statvfsp_t) buf;
414 		syscallarg(netbsd32_size_t) bufsize;
415 		syscallarg(int) flags;
416 	} */
417 
418 	return do_sys_getvfsstat(l, SCARG_P32(uap, buf), SCARG(uap, bufsize),
419 	    SCARG(uap, flags), netbds32_copyout_statvfs,
420 	    sizeof (struct netbsd32_statvfs), retval);
421 }
422 
423 int
424 netbsd32___fhstatvfs140(struct lwp *l, const struct netbsd32___fhstatvfs140_args *uap, register_t *retval)
425 {
426 	/* {
427 		syscallarg(const netbsd32_pointer_t) fhp;
428 		syscallarg(netbsd32_size_t) fh_size;
429 		syscallarg(netbsd32_statvfsp_t) buf;
430 		syscallarg(int) flags;
431 	} */
432 	struct statvfs *sb;
433 	int error;
434 
435 	sb = STATVFSBUF_GET();
436 	error = do_fhstatvfs(l, SCARG_P32(uap, fhp), SCARG(uap, fh_size), sb,
437 	    SCARG(uap, flags));
438 
439 	if (error == 0)
440 		error = netbds32_copyout_statvfs(sb, SCARG_P32(uap, buf), 0);
441 	STATVFSBUF_PUT(sb);
442 
443 	return error;
444 }
445 
446 int
447 netbsd32___futimes50(struct lwp *l, const struct netbsd32___futimes50_args *uap, register_t *retval)
448 {
449 	/* {
450 		syscallarg(int) fd;
451 		syscallarg(const netbsd32_timevalp_t) tptr;
452 	} */
453 	int error;
454 	file_t *fp;
455 	struct timeval tv[2], *tvp;
456 
457 	error = get_utimes32(SCARG_P32(uap, tptr), tv, &tvp);
458 	if (error != 0)
459 		return error;
460 
461 	/* fd_getvnode() will use the descriptor for us */
462 	if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0)
463 		return (error);
464 
465 	error = do_sys_utimes(l, fp->f_data, NULL, 0, tvp, UIO_SYSSPACE);
466 
467 	fd_putfile(SCARG(uap, fd));
468 	return (error);
469 }
470 
471 int
472 netbsd32___getdents30(struct lwp *l,
473     const struct netbsd32___getdents30_args *uap, register_t *retval)
474 {
475 	/* {
476 		syscallarg(int) fd;
477 		syscallarg(netbsd32_charp) buf;
478 		syscallarg(netbsd32_size_t) count;
479 	} */
480 	file_t *fp;
481 	int error, done;
482 
483 	/* fd_getvnode() will use the descriptor for us */
484 	if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0)
485 		return (error);
486 	if ((fp->f_flag & FREAD) == 0) {
487 		error = EBADF;
488 		goto out;
489 	}
490 	error = vn_readdir(fp, SCARG_P32(uap, buf),
491 	    UIO_USERSPACE, SCARG(uap, count), &done, l, 0, 0);
492 	*retval = done;
493  out:
494 	fd_putfile(SCARG(uap, fd));
495 	return (error);
496 }
497 
498 int
499 netbsd32___lutimes50(struct lwp *l,
500     const struct netbsd32___lutimes50_args *uap, register_t *retval)
501 {
502 	/* {
503 		syscallarg(const netbsd32_charp) path;
504 		syscallarg(const netbsd32_timevalp_t) tptr;
505 	} */
506 	int error;
507 	struct timeval tv[2], *tvp;
508 
509 	error = get_utimes32(SCARG_P32(uap, tptr), tv, &tvp);
510 	if (error != 0)
511 		return error;
512 
513 	return do_sys_utimes(l, NULL, SCARG_P32(uap, path), NOFOLLOW,
514 			    tvp, UIO_SYSSPACE);
515 }
516 
517 int
518 netbsd32___stat50(struct lwp *l, const struct netbsd32___stat50_args *uap, register_t *retval)
519 {
520 	/* {
521 		syscallarg(const netbsd32_charp) path;
522 		syscallarg(netbsd32_statp_t) ub;
523 	} */
524 	struct netbsd32_stat sb32;
525 	struct stat sb;
526 	int error;
527 	const char *path;
528 
529 	path = SCARG_P32(uap, path);
530 
531 	error = do_sys_stat(path, FOLLOW, &sb);
532 	if (error)
533 		return (error);
534 	netbsd32_from_stat(&sb, &sb32);
535 	error = copyout(&sb32, SCARG_P32(uap, ub), sizeof(sb32));
536 	return (error);
537 }
538 
539 int
540 netbsd32___fstat50(struct lwp *l, const struct netbsd32___fstat50_args *uap, register_t *retval)
541 {
542 	/* {
543 		syscallarg(int) fd;
544 		syscallarg(netbsd32_statp_t) sb;
545 	} */
546 	struct netbsd32_stat sb32;
547 	struct stat ub;
548 	int error;
549 
550 	error = do_sys_fstat(SCARG(uap, fd), &ub);
551 	if (error == 0) {
552 		netbsd32_from_stat(&ub, &sb32);
553 		error = copyout(&sb32, SCARG_P32(uap, sb), sizeof(sb32));
554 	}
555 	return (error);
556 }
557 
558 int
559 netbsd32___lstat50(struct lwp *l, const struct netbsd32___lstat50_args *uap, register_t *retval)
560 {
561 	/* {
562 		syscallarg(const netbsd32_charp) path;
563 		syscallarg(netbsd32_statp_t) ub;
564 	} */
565 	struct netbsd32_stat sb32;
566 	struct stat sb;
567 	int error;
568 	const char *path;
569 
570 	path = SCARG_P32(uap, path);
571 
572 	error = do_sys_stat(path, NOFOLLOW, &sb);
573 	if (error)
574 		return (error);
575 	netbsd32_from_stat(&sb, &sb32);
576 	error = copyout(&sb32, SCARG_P32(uap, ub), sizeof(sb32));
577 	return (error);
578 }
579 
580 int
581 netbsd32___fhstat50(struct lwp *l, const struct netbsd32___fhstat50_args *uap, register_t *retval)
582 {
583 	/* {
584 		syscallarg(const netbsd32_pointer_t) fhp;
585 		syscallarg(netbsd32_size_t) fh_size;
586 		syscallarg(netbsd32_statp_t) sb;
587 	} */
588 	struct stat sb;
589 	struct netbsd32_stat sb32;
590 	int error;
591 
592 	error = do_fhstat(l, SCARG_P32(uap, fhp), SCARG(uap, fh_size), &sb);
593 	if (error != 0) {
594 		netbsd32_from_stat(&sb, &sb32);
595 		error = copyout(&sb32, SCARG_P32(uap, sb), sizeof(sb));
596 	}
597 	return error;
598 }
599 
600 int
601 netbsd32_preadv(struct lwp *l, const struct netbsd32_preadv_args *uap, register_t *retval)
602 {
603 	/* {
604 		syscallarg(int) fd;
605 		syscallarg(const netbsd32_iovecp_t) iovp;
606 		syscallarg(int) iovcnt;
607 		syscallarg(int) pad;
608 		syscallarg(off_t) offset;
609 	} */
610 	file_t *fp;
611 	struct vnode *vp;
612 	off_t offset;
613 	int error, fd = SCARG(uap, fd);
614 
615 	if ((fp = fd_getfile(fd)) == NULL)
616 		return (EBADF);
617 
618 	if ((fp->f_flag & FREAD) == 0) {
619 		fd_putfile(fd);
620 		return (EBADF);
621 	}
622 
623 	vp = fp->f_data;
624 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO) {
625 		error = ESPIPE;
626 		goto out;
627 	}
628 
629 	offset = SCARG(uap, offset);
630 
631 	/*
632 	 * XXX This works because no file systems actually
633 	 * XXX take any action on the seek operation.
634 	 */
635 	if ((error = VOP_SEEK(vp, fp->f_offset, offset, fp->f_cred)) != 0)
636 		goto out;
637 
638 	return (dofilereadv32(fd, fp, SCARG_P32(uap, iovp),
639 	    SCARG(uap, iovcnt), &offset, 0, retval));
640 
641 out:
642 	fd_putfile(fd);
643 	return (error);
644 }
645 
646 int
647 netbsd32_pwritev(struct lwp *l, const struct netbsd32_pwritev_args *uap, register_t *retval)
648 {
649 	/* {
650 		syscallarg(int) fd;
651 		syscallarg(const netbsd32_iovecp_t) iovp;
652 		syscallarg(int) iovcnt;
653 		syscallarg(int) pad;
654 		syscallarg(off_t) offset;
655 	} */
656 	file_t *fp;
657 	struct vnode *vp;
658 	off_t offset;
659 	int error, fd = SCARG(uap, fd);
660 
661 	if ((fp = fd_getfile(fd)) == NULL)
662 		return (EBADF);
663 
664 	if ((fp->f_flag & FWRITE) == 0) {
665 		fd_putfile(fd);
666 		return (EBADF);
667 	}
668 
669 	vp = fp->f_data;
670 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO) {
671 		error = ESPIPE;
672 		goto out;
673 	}
674 
675 	offset = SCARG(uap, offset);
676 
677 	/*
678 	 * XXX This works because no file systems actually
679 	 * XXX take any action on the seek operation.
680 	 */
681 	if ((error = VOP_SEEK(vp, fp->f_offset, offset, fp->f_cred)) != 0)
682 		goto out;
683 
684 	return (dofilewritev32(fd, fp, SCARG_P32(uap, iovp),
685 	    SCARG(uap, iovcnt), &offset, 0, retval));
686 
687 out:
688 	fd_putfile(fd);
689 	return (error);
690 }
691 
692 /*
693  * Find pathname of process's current directory.
694  *
695  * Use vfs vnode-to-name reverse cache; if that fails, fall back
696  * to reading directory contents.
697  */
698 /* XXX NH Why does this exist */
699 int
700 getcwd_common(struct vnode *, struct vnode *,
701 		   char **, char *, int, int, struct lwp *);
702 
703 int
704 netbsd32___getcwd(struct lwp *l, const struct netbsd32___getcwd_args *uap, register_t *retval)
705 {
706 	/* {
707 		syscallarg(char *) bufp;
708 		syscallarg(size_t) length;
709 	} */
710 	struct proc *p = l->l_proc;
711 	int     error;
712 	char   *path;
713 	char   *bp, *bend;
714 	int     len = (int)SCARG(uap, length);
715 	int	lenused;
716 	struct	cwdinfo *cwdi;
717 
718 	if (len > MAXPATHLEN*4)
719 		len = MAXPATHLEN*4;
720 	else if (len < 2)
721 		return ERANGE;
722 
723 	path = (char *)malloc(len, M_TEMP, M_WAITOK);
724 	if (!path)
725 		return ENOMEM;
726 
727 	bp = &path[len];
728 	bend = bp;
729 	*(--bp) = '\0';
730 
731 	/*
732 	 * 5th argument here is "max number of vnodes to traverse".
733 	 * Since each entry takes up at least 2 bytes in the output buffer,
734 	 * limit it to N/2 vnodes for an N byte buffer.
735 	 */
736 #define GETCWD_CHECK_ACCESS 0x0001
737 	cwdi = p->p_cwdi;
738 	rw_enter(&cwdi->cwdi_lock, RW_READER);
739 	error = getcwd_common (cwdi->cwdi_cdir, NULL, &bp, path, len/2,
740 			       GETCWD_CHECK_ACCESS, l);
741 	rw_exit(&cwdi->cwdi_lock);
742 
743 	if (error)
744 		goto out;
745 	lenused = bend - bp;
746 	*retval = lenused;
747 	/* put the result into user buffer */
748 	error = copyout(bp, SCARG_P32(uap, bufp), lenused);
749 
750 out:
751 	free(path, M_TEMP);
752 	return error;
753 }
754