xref: /illumos-gate/usr/src/uts/common/syscall/sendfile.c (revision b3528fae2e7d55d6f5555957b7734028555131b8)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <sys/types.h>
28 #include <sys/t_lock.h>
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/buf.h>
32 #include <sys/conf.h>
33 #include <sys/cred.h>
34 #include <sys/kmem.h>
35 #include <sys/sysmacros.h>
36 #include <sys/vfs.h>
37 #include <sys/vnode.h>
38 #include <sys/debug.h>
39 #include <sys/errno.h>
40 #include <sys/time.h>
41 #include <sys/file.h>
42 #include <sys/open.h>
43 #include <sys/user.h>
44 #include <sys/termios.h>
45 #include <sys/stream.h>
46 #include <sys/strsubr.h>
47 #include <sys/sunddi.h>
48 #include <sys/esunddi.h>
49 #include <sys/flock.h>
50 #include <sys/modctl.h>
51 #include <sys/cmn_err.h>
52 #include <sys/vmsystm.h>
53 
54 #include <sys/socket.h>
55 #include <sys/socketvar.h>
56 #include <fs/sockfs/sockcommon.h>
57 #include <fs/sockfs/socktpi.h>
58 
59 #include <netinet/in.h>
60 #include <sys/sendfile.h>
61 #include <sys/un.h>
62 #include <sys/tihdr.h>
63 #include <sys/atomic.h>
64 
65 #include <inet/common.h>
66 #include <inet/ip.h>
67 #include <inet/ip6.h>
68 #include <inet/tcp.h>
69 
70 extern int sosendfile64(file_t *, file_t *, const struct ksendfilevec64 *,
71 		ssize32_t *);
72 extern int nl7c_sendfilev(struct sonode *, u_offset_t *, struct sendfilevec *,
73 		int, ssize_t *);
74 extern int snf_segmap(file_t *, vnode_t *, u_offset_t, u_offset_t, ssize_t *,
75 		boolean_t);
76 extern sotpi_info_t *sotpi_sototpi(struct sonode *);
77 
78 #define	SEND_MAX_CHUNK	16
79 
80 #if defined(_SYSCALL32_IMPL) || defined(_ILP32)
81 /*
82  * 64 bit offsets for 32 bit applications only running either on
83  * 64 bit kernel or 32 bit kernel. For 32 bit apps, we can't transfer
84  * more than 2GB of data.
85  */
86 int
87 sendvec_chunk64(file_t *fp, u_offset_t *fileoff, struct ksendfilevec64 *sfv,
88     int copy_cnt, ssize32_t *count)
89 {
90 	struct vnode *vp;
91 	ushort_t fflag;
92 	int ioflag;
93 	size32_t cnt;
94 	ssize32_t sfv_len;
95 	ssize32_t tmpcount;
96 	u_offset_t sfv_off;
97 	struct uio auio;
98 	struct iovec aiov;
99 	int i, error;
100 
101 	fflag = fp->f_flag;
102 	vp = fp->f_vnode;
103 	for (i = 0; i < copy_cnt; i++) {
104 
105 		if (ISSIG(curthread, JUSTLOOKING))
106 			return (EINTR);
107 
108 		/*
109 		 * Do similar checks as "write" as we are writing
110 		 * sfv_len bytes into "vp".
111 		 */
112 		sfv_len = (ssize32_t)sfv->sfv_len;
113 
114 		if (sfv_len == 0) {
115 			sfv++;
116 			continue;
117 		}
118 
119 		if (sfv_len < 0)
120 			return (EINVAL);
121 
122 		if (vp->v_type == VREG) {
123 			if (*fileoff >= curproc->p_fsz_ctl) {
124 				mutex_enter(&curproc->p_lock);
125 				(void) rctl_action(
126 				    rctlproc_legacy[RLIMIT_FSIZE],
127 				    curproc->p_rctls, curproc, RCA_SAFE);
128 				mutex_exit(&curproc->p_lock);
129 				return (EFBIG);
130 			}
131 
132 			if (*fileoff >= OFFSET_MAX(fp))
133 				return (EFBIG);
134 
135 			if (*fileoff + sfv_len > OFFSET_MAX(fp))
136 				return (EINVAL);
137 		}
138 
139 		tmpcount = *count + sfv_len;
140 		if (tmpcount < 0)
141 			return (EINVAL);
142 
143 		sfv_off = sfv->sfv_off;
144 
145 		auio.uio_extflg = UIO_COPY_DEFAULT;
146 		if (sfv->sfv_fd == SFV_FD_SELF) {
147 			aiov.iov_len = sfv_len;
148 			aiov.iov_base = (caddr_t)(uintptr_t)sfv_off;
149 			auio.uio_loffset = *fileoff;
150 			auio.uio_iovcnt = 1;
151 			auio.uio_resid = sfv_len;
152 			auio.uio_iov = &aiov;
153 			auio.uio_segflg = UIO_USERSPACE;
154 			auio.uio_llimit = curproc->p_fsz_ctl;
155 			auio.uio_fmode = fflag;
156 			ioflag = auio.uio_fmode & (FAPPEND|FSYNC|FDSYNC|FRSYNC);
157 			while (sfv_len > 0) {
158 				error = VOP_WRITE(vp, &auio, ioflag,
159 				    fp->f_cred, NULL);
160 				cnt = sfv_len - auio.uio_resid;
161 				sfv_len -= cnt;
162 				ttolwp(curthread)->lwp_ru.ioch += (ulong_t)cnt;
163 				if (vp->v_type == VREG)
164 					*fileoff += cnt;
165 				*count += cnt;
166 				if (error != 0)
167 					return (error);
168 			}
169 		} else {
170 			file_t	*ffp;
171 			vnode_t	*readvp;
172 			size_t	size;
173 			caddr_t	ptr;
174 
175 			if ((ffp = getf(sfv->sfv_fd)) == NULL)
176 				return (EBADF);
177 
178 			if ((ffp->f_flag & FREAD) == 0) {
179 				releasef(sfv->sfv_fd);
180 				return (EBADF);
181 			}
182 
183 			readvp = ffp->f_vnode;
184 			if (readvp->v_type != VREG) {
185 				releasef(sfv->sfv_fd);
186 				return (EINVAL);
187 			}
188 
189 			/*
190 			 * No point reading and writing to same vp,
191 			 * as long as both are regular files. readvp is not
192 			 * locked; but since we got it from an open file the
193 			 * contents will be valid during the time of access.
194 			 */
195 			if (vn_compare(vp, readvp)) {
196 				releasef(sfv->sfv_fd);
197 				return (EINVAL);
198 			}
199 
200 			/*
201 			 * Optimize the regular file over
202 			 * the socket case.
203 			 */
204 			if (vp->v_type == VSOCK) {
205 				error = sosendfile64(fp, ffp, sfv, count);
206 				if (error)
207 					return (error);
208 				sfv++;
209 				continue;
210 			}
211 
212 			/*
213 			 * Note: we assume readvp != vp. "vp" is already
214 			 * locked, and "readvp" must not be.
215 			 */
216 			if (readvp < vp) {
217 				VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
218 				(void) VOP_RWLOCK(readvp, V_WRITELOCK_FALSE,
219 				    NULL);
220 				(void) VOP_RWLOCK(vp, V_WRITELOCK_TRUE, NULL);
221 			} else {
222 				(void) VOP_RWLOCK(readvp, V_WRITELOCK_FALSE,
223 				    NULL);
224 			}
225 
226 			/*
227 			 * Same checks as in pread64.
228 			 */
229 			if (sfv_off > MAXOFFSET_T) {
230 				VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE, NULL);
231 				releasef(sfv->sfv_fd);
232 				return (EINVAL);
233 			}
234 
235 			if (sfv_off + sfv_len > MAXOFFSET_T)
236 				sfv_len = (ssize32_t)(MAXOFFSET_T - sfv_off);
237 
238 			/* Find the native blocksize to transfer data */
239 			size = MIN(vp->v_vfsp->vfs_bsize,
240 			    readvp->v_vfsp->vfs_bsize);
241 			size = sfv_len < size ? sfv_len : size;
242 			ptr = kmem_alloc(size, KM_NOSLEEP);
243 			if (ptr == NULL) {
244 				VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE, NULL);
245 				releasef(sfv->sfv_fd);
246 				return (ENOMEM);
247 			}
248 
249 			while (sfv_len > 0) {
250 				size_t	iov_len;
251 
252 				iov_len = MIN(size, sfv_len);
253 				aiov.iov_base = ptr;
254 				aiov.iov_len = iov_len;
255 				auio.uio_loffset = sfv_off;
256 				auio.uio_iov = &aiov;
257 				auio.uio_iovcnt = 1;
258 				auio.uio_resid = iov_len;
259 				auio.uio_segflg = UIO_SYSSPACE;
260 				auio.uio_llimit = MAXOFFSET_T;
261 				auio.uio_fmode = ffp->f_flag;
262 				ioflag = auio.uio_fmode &
263 				    (FAPPEND|FSYNC|FDSYNC|FRSYNC);
264 
265 				/*
266 				 * If read sync is not asked for,
267 				 * filter sync flags
268 				 */
269 				if ((ioflag & FRSYNC) == 0)
270 					ioflag &= ~(FSYNC|FDSYNC);
271 				error = VOP_READ(readvp, &auio, ioflag,
272 				    fp->f_cred, NULL);
273 				if (error) {
274 					kmem_free(ptr, size);
275 					VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE,
276 					    NULL);
277 					releasef(sfv->sfv_fd);
278 					return (error);
279 				}
280 
281 				/*
282 				 * Check how must data was really read.
283 				 * Decrement the 'len' and increment the
284 				 * 'off' appropriately.
285 				 */
286 				cnt = iov_len - auio.uio_resid;
287 				if (cnt == 0) {
288 					/*
289 					 * If we were reading a pipe (currently
290 					 * not implemented), we may now lose
291 					 * data.
292 					 */
293 					kmem_free(ptr, size);
294 					VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE,
295 					    NULL);
296 					releasef(sfv->sfv_fd);
297 					return (EINVAL);
298 				}
299 				sfv_len -= cnt;
300 				sfv_off += cnt;
301 
302 				aiov.iov_base = ptr;
303 				aiov.iov_len = cnt;
304 				auio.uio_loffset = *fileoff;
305 				auio.uio_iov = &aiov;
306 				auio.uio_iovcnt = 1;
307 				auio.uio_resid = cnt;
308 				auio.uio_segflg = UIO_SYSSPACE;
309 				auio.uio_llimit = curproc->p_fsz_ctl;
310 				auio.uio_fmode = fflag;
311 				ioflag = auio.uio_fmode &
312 				    (FAPPEND|FSYNC|FDSYNC|FRSYNC);
313 				error = VOP_WRITE(vp, &auio, ioflag,
314 				    fp->f_cred, NULL);
315 
316 				/*
317 				 * Check how much data was written. Increment
318 				 * the 'len' and decrement the 'off' if all
319 				 * the data was not written.
320 				 */
321 				cnt -= auio.uio_resid;
322 				sfv_len += auio.uio_resid;
323 				sfv_off -= auio.uio_resid;
324 				ttolwp(curthread)->lwp_ru.ioch += (ulong_t)cnt;
325 				if (vp->v_type == VREG)
326 					*fileoff += cnt;
327 				*count += cnt;
328 				if (error != 0) {
329 					kmem_free(ptr, size);
330 					VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE,
331 					    NULL);
332 					releasef(sfv->sfv_fd);
333 					return (error);
334 				}
335 			}
336 			VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE, NULL);
337 			releasef(sfv->sfv_fd);
338 			kmem_free(ptr, size);
339 		}
340 		sfv++;
341 	}
342 	return (0);
343 }
344 
345 ssize32_t
346 sendvec64(file_t *fp, const struct ksendfilevec64 *vec, int sfvcnt,
347 	size32_t *xferred, int fildes)
348 {
349 	u_offset_t		fileoff;
350 	int			copy_cnt;
351 	const struct ksendfilevec64 *copy_vec;
352 	struct ksendfilevec64 sfv[SEND_MAX_CHUNK];
353 	struct vnode *vp;
354 	int error;
355 	ssize32_t count = 0;
356 
357 	vp = fp->f_vnode;
358 	(void) VOP_RWLOCK(vp, V_WRITELOCK_TRUE, NULL);
359 
360 	copy_vec = vec;
361 	fileoff = fp->f_offset;
362 
363 	do {
364 		copy_cnt = MIN(sfvcnt, SEND_MAX_CHUNK);
365 		if (copyin(copy_vec, sfv, copy_cnt *
366 		    sizeof (struct ksendfilevec64))) {
367 			error = EFAULT;
368 			break;
369 		}
370 
371 		error = sendvec_chunk64(fp, &fileoff, sfv, copy_cnt, &count);
372 		if (error != 0)
373 			break;
374 
375 		copy_vec += copy_cnt;
376 		sfvcnt -= copy_cnt;
377 	} while (sfvcnt > 0);
378 
379 	if (vp->v_type == VREG)
380 		fp->f_offset += count;
381 
382 	VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
383 	if (copyout(&count, xferred, sizeof (count)))
384 		error = EFAULT;
385 	releasef(fildes);
386 	if (error != 0)
387 		return (set_errno(error));
388 	return (count);
389 }
390 #endif
391 
392 int
393 sendvec_small_chunk(file_t *fp, u_offset_t *fileoff, struct sendfilevec *sfv,
394     int copy_cnt, ssize_t total_size, int maxblk, ssize_t *count)
395 {
396 	struct vnode *vp;
397 	struct uio auio;
398 	struct iovec aiov;
399 	ushort_t fflag;
400 	int ioflag;
401 	int i, error;
402 	size_t cnt;
403 	ssize_t sfv_len;
404 	u_offset_t sfv_off;
405 #ifdef _SYSCALL32_IMPL
406 	model_t model = get_udatamodel();
407 	u_offset_t maxoff = (model == DATAMODEL_ILP32) ?
408 	    MAXOFF32_T : MAXOFFSET_T;
409 #else
410 	const u_offset_t maxoff = MAXOFF32_T;
411 #endif
412 	mblk_t *dmp = NULL;
413 	int wroff;
414 	int buf_left = 0;
415 	size_t	iov_len;
416 	mblk_t  *head, *tmp;
417 	size_t  size = total_size;
418 	size_t  extra;
419 	int tail_len;
420 	struct nmsghdr msg;
421 
422 	fflag = fp->f_flag;
423 	vp = fp->f_vnode;
424 
425 	ASSERT(vp->v_type == VSOCK);
426 	ASSERT(maxblk > 0);
427 
428 	/* If nothing to send, return */
429 	if (total_size == 0)
430 		return (0);
431 
432 	if (vp->v_stream != NULL) {
433 		wroff = (int)vp->v_stream->sd_wroff;
434 		tail_len = (int)vp->v_stream->sd_tail;
435 	} else {
436 		struct sonode *so;
437 
438 		so = VTOSO(vp);
439 		wroff = so->so_proto_props.sopp_wroff;
440 		tail_len = so->so_proto_props.sopp_tail;
441 	}
442 
443 	extra = wroff + tail_len;
444 
445 	buf_left = MIN(total_size, maxblk);
446 	head = dmp = allocb(buf_left + extra, BPRI_HI);
447 	if (head == NULL)
448 		return (ENOMEM);
449 	head->b_wptr = head->b_rptr = head->b_rptr + wroff;
450 	bzero(&msg, sizeof (msg));
451 
452 	auio.uio_extflg = UIO_COPY_DEFAULT;
453 	for (i = 0; i < copy_cnt; i++) {
454 		if (ISSIG(curthread, JUSTLOOKING)) {
455 			freemsg(head);
456 			return (EINTR);
457 		}
458 
459 		/*
460 		 * Do similar checks as "write" as we are writing
461 		 * sfv_len bytes into "vp".
462 		 */
463 		sfv_len = (ssize_t)sfv->sfv_len;
464 
465 		if (sfv_len == 0) {
466 			sfv++;
467 			continue;
468 		}
469 
470 		/* Check for overflow */
471 #ifdef _SYSCALL32_IMPL
472 		if (model == DATAMODEL_ILP32) {
473 			if (((ssize32_t)(*count + sfv_len)) < 0) {
474 				freemsg(head);
475 				return (EINVAL);
476 			}
477 		} else
478 #endif
479 		if ((*count + sfv_len) < 0) {
480 			freemsg(head);
481 			return (EINVAL);
482 		}
483 
484 		sfv_off = (u_offset_t)(ulong_t)sfv->sfv_off;
485 
486 		if (sfv->sfv_fd == SFV_FD_SELF) {
487 			while (sfv_len > 0) {
488 				if (buf_left == 0) {
489 					tmp = dmp;
490 					buf_left = MIN(total_size, maxblk);
491 					iov_len = MIN(buf_left, sfv_len);
492 					dmp = allocb(buf_left + extra, BPRI_HI);
493 					if (dmp == NULL) {
494 						freemsg(head);
495 						return (ENOMEM);
496 					}
497 					dmp->b_wptr = dmp->b_rptr =
498 					    dmp->b_rptr + wroff;
499 					tmp->b_cont = dmp;
500 				} else {
501 					iov_len = MIN(buf_left, sfv_len);
502 				}
503 
504 				aiov.iov_len = iov_len;
505 				aiov.iov_base = (caddr_t)(uintptr_t)sfv_off;
506 				auio.uio_loffset = *fileoff;
507 				auio.uio_iovcnt = 1;
508 				auio.uio_resid = iov_len;
509 				auio.uio_iov = &aiov;
510 				auio.uio_segflg = UIO_USERSPACE;
511 				auio.uio_llimit = curproc->p_fsz_ctl;
512 				auio.uio_fmode = fflag;
513 
514 				buf_left -= iov_len;
515 				total_size -= iov_len;
516 				sfv_len -= iov_len;
517 				sfv_off += iov_len;
518 
519 				error = uiomove((caddr_t)dmp->b_wptr,
520 				    iov_len, UIO_WRITE, &auio);
521 				if (error != 0) {
522 					freemsg(head);
523 					return (error);
524 				}
525 				dmp->b_wptr += iov_len;
526 			}
527 		} else {
528 			file_t	*ffp;
529 			vnode_t	*readvp;
530 
531 			if ((ffp = getf(sfv->sfv_fd)) == NULL) {
532 				freemsg(head);
533 				return (EBADF);
534 			}
535 
536 			if ((ffp->f_flag & FREAD) == 0) {
537 				releasef(sfv->sfv_fd);
538 				freemsg(head);
539 				return (EACCES);
540 			}
541 
542 			readvp = ffp->f_vnode;
543 			if (readvp->v_type != VREG) {
544 				releasef(sfv->sfv_fd);
545 				freemsg(head);
546 				return (EINVAL);
547 			}
548 
549 			/*
550 			 * No point reading and writing to same vp,
551 			 * as long as both are regular files. readvp is not
552 			 * locked; but since we got it from an open file the
553 			 * contents will be valid during the time of access.
554 			 */
555 
556 			if (vn_compare(vp, readvp)) {
557 				releasef(sfv->sfv_fd);
558 				freemsg(head);
559 				return (EINVAL);
560 			}
561 
562 			/*
563 			 * Note: we assume readvp != vp. "vp" is already
564 			 * locked, and "readvp" must not be.
565 			 */
566 
567 			if (readvp < vp) {
568 				VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
569 				(void) VOP_RWLOCK(readvp, V_WRITELOCK_FALSE,
570 				    NULL);
571 				(void) VOP_RWLOCK(vp, V_WRITELOCK_TRUE, NULL);
572 			} else {
573 				(void) VOP_RWLOCK(readvp, V_WRITELOCK_FALSE,
574 				    NULL);
575 			}
576 
577 			/* Same checks as in pread */
578 			if (sfv_off > maxoff) {
579 				VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE, NULL);
580 				releasef(sfv->sfv_fd);
581 				freemsg(head);
582 				return (EINVAL);
583 			}
584 			if (sfv_off + sfv_len > maxoff) {
585 				total_size -= (sfv_off + sfv_len - maxoff);
586 				sfv_len = (ssize_t)((offset_t)maxoff -
587 				    sfv_off);
588 			}
589 
590 			while (sfv_len > 0) {
591 				if (buf_left == 0) {
592 					tmp = dmp;
593 					buf_left = MIN(total_size, maxblk);
594 					iov_len = MIN(buf_left, sfv_len);
595 					dmp = allocb(buf_left + extra, BPRI_HI);
596 					if (dmp == NULL) {
597 						VOP_RWUNLOCK(readvp,
598 						    V_WRITELOCK_FALSE, NULL);
599 						releasef(sfv->sfv_fd);
600 						freemsg(head);
601 						return (ENOMEM);
602 					}
603 					dmp->b_wptr = dmp->b_rptr =
604 					    dmp->b_rptr + wroff;
605 					tmp->b_cont = dmp;
606 				} else {
607 					iov_len = MIN(buf_left, sfv_len);
608 				}
609 				aiov.iov_base = (caddr_t)dmp->b_wptr;
610 				aiov.iov_len = iov_len;
611 				auio.uio_loffset = sfv_off;
612 				auio.uio_iov = &aiov;
613 				auio.uio_iovcnt = 1;
614 				auio.uio_resid = iov_len;
615 				auio.uio_segflg = UIO_SYSSPACE;
616 				auio.uio_llimit = MAXOFFSET_T;
617 				auio.uio_fmode = ffp->f_flag;
618 				ioflag = auio.uio_fmode &
619 				    (FAPPEND|FSYNC|FDSYNC|FRSYNC);
620 
621 				/*
622 				 * If read sync is not asked for,
623 				 * filter sync flags
624 				 */
625 				if ((ioflag & FRSYNC) == 0)
626 					ioflag &= ~(FSYNC|FDSYNC);
627 				error = VOP_READ(readvp, &auio, ioflag,
628 				    fp->f_cred, NULL);
629 				if (error != 0) {
630 					/*
631 					 * If we were reading a pipe (currently
632 					 * not implemented), we may now loose
633 					 * data.
634 					 */
635 					VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE,
636 					    NULL);
637 					releasef(sfv->sfv_fd);
638 					freemsg(head);
639 					return (error);
640 				}
641 
642 				/*
643 				 * Check how much data was really read.
644 				 * Decrement the 'len' and increment the
645 				 * 'off' appropriately.
646 				 */
647 				cnt = iov_len - auio.uio_resid;
648 				if (cnt == 0) {
649 					VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE,
650 					    NULL);
651 					releasef(sfv->sfv_fd);
652 					freemsg(head);
653 					return (EINVAL);
654 				}
655 				sfv_len -= cnt;
656 				sfv_off += cnt;
657 				total_size -= cnt;
658 				buf_left -= cnt;
659 
660 				dmp->b_wptr += cnt;
661 			}
662 			VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE, NULL);
663 			releasef(sfv->sfv_fd);
664 		}
665 		sfv++;
666 	}
667 
668 	ASSERT(total_size == 0);
669 	error = socket_sendmblk(VTOSO(vp), &msg, fflag, CRED(), &head);
670 	if (error != 0) {
671 		if (head != NULL)
672 			freemsg(head);
673 		return (error);
674 	}
675 	ttolwp(curthread)->lwp_ru.ioch += (ulong_t)size;
676 	*count += size;
677 
678 	return (0);
679 }
680 
681 
682 int
683 sendvec_chunk(file_t *fp, u_offset_t *fileoff, struct sendfilevec *sfv,
684     int copy_cnt, ssize_t *count)
685 {
686 	struct vnode *vp;
687 	struct uio auio;
688 	struct iovec aiov;
689 	ushort_t fflag;
690 	int ioflag;
691 	int i, error;
692 	size_t cnt;
693 	ssize_t sfv_len;
694 	u_offset_t sfv_off;
695 #ifdef _SYSCALL32_IMPL
696 	model_t model = get_udatamodel();
697 	u_offset_t maxoff = (model == DATAMODEL_ILP32) ?
698 	    MAXOFF32_T : MAXOFFSET_T;
699 #else
700 	const u_offset_t maxoff = MAXOFF32_T;
701 #endif
702 	mblk_t	*dmp = NULL;
703 	char	*buf = NULL;
704 	size_t  extra;
705 	int maxblk, wroff, tail_len;
706 	struct sonode *so;
707 	stdata_t *stp;
708 	struct nmsghdr msg;
709 
710 	fflag = fp->f_flag;
711 	vp = fp->f_vnode;
712 
713 	if (vp->v_type == VSOCK) {
714 		so = VTOSO(vp);
715 		if (vp->v_stream != NULL) {
716 			stp = vp->v_stream;
717 			wroff = (int)stp->sd_wroff;
718 			tail_len = (int)stp->sd_tail;
719 			maxblk = (int)stp->sd_maxblk;
720 		} else {
721 			stp = NULL;
722 			wroff = so->so_proto_props.sopp_wroff;
723 			tail_len = so->so_proto_props.sopp_tail;
724 			maxblk = so->so_proto_props.sopp_maxblk;
725 		}
726 		extra = wroff + tail_len;
727 	}
728 
729 	bzero(&msg, sizeof (msg));
730 	auio.uio_extflg = UIO_COPY_DEFAULT;
731 	for (i = 0; i < copy_cnt; i++) {
732 		if (ISSIG(curthread, JUSTLOOKING))
733 			return (EINTR);
734 
735 		/*
736 		 * Do similar checks as "write" as we are writing
737 		 * sfv_len bytes into "vp".
738 		 */
739 		sfv_len = (ssize_t)sfv->sfv_len;
740 
741 		if (sfv_len == 0) {
742 			sfv++;
743 			continue;
744 		}
745 
746 		if (vp->v_type == VREG) {
747 			if (*fileoff >= curproc->p_fsz_ctl) {
748 				mutex_enter(&curproc->p_lock);
749 				(void) rctl_action(
750 				    rctlproc_legacy[RLIMIT_FSIZE],
751 				    curproc->p_rctls, curproc, RCA_SAFE);
752 				mutex_exit(&curproc->p_lock);
753 
754 				return (EFBIG);
755 			}
756 
757 			if (*fileoff >= maxoff)
758 				return (EFBIG);
759 
760 			if (*fileoff + sfv_len > maxoff)
761 				return (EINVAL);
762 		}
763 
764 		/* Check for overflow */
765 #ifdef _SYSCALL32_IMPL
766 		if (model == DATAMODEL_ILP32) {
767 			if (((ssize32_t)(*count + sfv_len)) < 0)
768 				return (EINVAL);
769 		} else
770 #endif
771 		if ((*count + sfv_len) < 0)
772 			return (EINVAL);
773 
774 		sfv_off = (u_offset_t)(ulong_t)sfv->sfv_off;
775 
776 		if (sfv->sfv_fd == SFV_FD_SELF) {
777 			if (vp->v_type == VSOCK) {
778 				while (sfv_len > 0) {
779 					size_t iov_len;
780 
781 					iov_len = sfv_len;
782 					if (!SOCK_IS_NONSTR(so) &&
783 					    SOTOTPI(so)->sti_kssl_ctx != NULL)
784 						iov_len = MIN(iov_len, maxblk);
785 
786 					aiov.iov_len = iov_len;
787 					aiov.iov_base =
788 					    (caddr_t)(uintptr_t)sfv_off;
789 
790 					auio.uio_iov = &aiov;
791 					auio.uio_iovcnt = 1;
792 					auio.uio_loffset = *fileoff;
793 					auio.uio_segflg = UIO_USERSPACE;
794 					auio.uio_fmode = fflag;
795 					auio.uio_llimit = curproc->p_fsz_ctl;
796 					auio.uio_resid = iov_len;
797 
798 					dmp = allocb(iov_len + extra, BPRI_HI);
799 					if (dmp == NULL)
800 						return (ENOMEM);
801 					dmp->b_wptr = dmp->b_rptr =
802 					    dmp->b_rptr + wroff;
803 					error = uiomove((caddr_t)dmp->b_wptr,
804 					    iov_len, UIO_WRITE, &auio);
805 					if (error != 0) {
806 						freeb(dmp);
807 						return (error);
808 					}
809 					dmp->b_wptr += iov_len;
810 					error = socket_sendmblk(VTOSO(vp),
811 					    &msg, fflag, CRED(), &dmp);
812 
813 					if (error != 0) {
814 						if (dmp != NULL)
815 							freeb(dmp);
816 						return (error);
817 					}
818 					ttolwp(curthread)->lwp_ru.ioch +=
819 					    (ulong_t)iov_len;
820 					*count += iov_len;
821 					sfv_len -= iov_len;
822 					sfv_off += iov_len;
823 				}
824 			} else {
825 				aiov.iov_len = sfv_len;
826 				aiov.iov_base = (caddr_t)(uintptr_t)sfv_off;
827 
828 				auio.uio_iov = &aiov;
829 				auio.uio_iovcnt = 1;
830 				auio.uio_loffset = *fileoff;
831 				auio.uio_segflg = UIO_USERSPACE;
832 				auio.uio_fmode = fflag;
833 				auio.uio_llimit = curproc->p_fsz_ctl;
834 				auio.uio_resid = sfv_len;
835 
836 				ioflag = auio.uio_fmode &
837 				    (FAPPEND|FSYNC|FDSYNC|FRSYNC);
838 				while (sfv_len > 0) {
839 					error = VOP_WRITE(vp, &auio, ioflag,
840 					    fp->f_cred, NULL);
841 					cnt = sfv_len - auio.uio_resid;
842 					sfv_len -= cnt;
843 					ttolwp(curthread)->lwp_ru.ioch +=
844 					    (ulong_t)cnt;
845 					*fileoff += cnt;
846 					*count += cnt;
847 					if (error != 0)
848 						return (error);
849 				}
850 			}
851 		} else {
852 			int segmapit = 0;
853 			file_t	*ffp;
854 			vnode_t	*readvp;
855 			struct vnode *realvp;
856 			size_t	size;
857 			caddr_t	ptr;
858 
859 			if ((ffp = getf(sfv->sfv_fd)) == NULL)
860 				return (EBADF);
861 
862 			if ((ffp->f_flag & FREAD) == 0) {
863 				releasef(sfv->sfv_fd);
864 				return (EBADF);
865 			}
866 
867 			readvp = ffp->f_vnode;
868 			if (VOP_REALVP(readvp, &realvp, NULL) == 0)
869 				readvp = realvp;
870 			if (readvp->v_type != VREG) {
871 				releasef(sfv->sfv_fd);
872 				return (EINVAL);
873 			}
874 
875 			/*
876 			 * No point reading and writing to same vp,
877 			 * as long as both are regular files. readvp is not
878 			 * locked; but since we got it from an open file the
879 			 * contents will be valid during the time of access.
880 			 */
881 			if (vn_compare(vp, readvp)) {
882 				releasef(sfv->sfv_fd);
883 				return (EINVAL);
884 			}
885 
886 			/*
887 			 * Note: we assume readvp != vp. "vp" is already
888 			 * locked, and "readvp" must not be.
889 			 */
890 			if (readvp < vp) {
891 				VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
892 				(void) VOP_RWLOCK(readvp, V_WRITELOCK_FALSE,
893 				    NULL);
894 				(void) VOP_RWLOCK(vp, V_WRITELOCK_TRUE, NULL);
895 			} else {
896 				(void) VOP_RWLOCK(readvp, V_WRITELOCK_FALSE,
897 				    NULL);
898 			}
899 
900 			/* Same checks as in pread */
901 			if (sfv_off > maxoff) {
902 				VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE, NULL);
903 				releasef(sfv->sfv_fd);
904 				return (EINVAL);
905 			}
906 			if (sfv_off + sfv_len > maxoff) {
907 				sfv_len = (ssize_t)((offset_t)maxoff -
908 				    sfv_off);
909 			}
910 			/* Find the native blocksize to transfer data */
911 			size = MIN(vp->v_vfsp->vfs_bsize,
912 			    readvp->v_vfsp->vfs_bsize);
913 			size = sfv_len < size ? sfv_len : size;
914 
915 			if (vp->v_type != VSOCK) {
916 				segmapit = 0;
917 				buf = kmem_alloc(size, KM_NOSLEEP);
918 				if (buf == NULL) {
919 					VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE,
920 					    NULL);
921 					releasef(sfv->sfv_fd);
922 					return (ENOMEM);
923 				}
924 			} else {
925 				uint_t	copyflag;
926 
927 				copyflag = stp != NULL ? stp->sd_copyflag :
928 				    so->so_proto_props.sopp_zcopyflag;
929 				/*
930 				 * For sockets acting as an SSL proxy, we
931 				 * need to adjust the size to the maximum
932 				 * SSL record size set in the stream head.
933 				 */
934 				if (!SOCK_IS_NONSTR(so) &&
935 				    _SOTOTPI(so)->sti_kssl_ctx != NULL)
936 					size = MIN(size, maxblk);
937 
938 				if (vn_has_flocks(readvp) ||
939 				    readvp->v_flag & VNOMAP ||
940 				    copyflag & STZCVMUNSAFE) {
941 					segmapit = 0;
942 				} else if (copyflag & STZCVMSAFE) {
943 					segmapit = 1;
944 				} else {
945 					int on = 1;
946 					if (socket_setsockopt(VTOSO(vp),
947 					    SOL_SOCKET, SO_SND_COPYAVOID,
948 					    &on, sizeof (on), CRED()) == 0)
949 					segmapit = 1;
950 				}
951 			}
952 
953 			if (segmapit) {
954 				boolean_t nowait;
955 
956 				nowait = (sfv->sfv_flag & SFV_NOWAIT) != 0;
957 				error = snf_segmap(fp, readvp, sfv_off,
958 				    (u_offset_t)sfv_len, (ssize_t *)&cnt,
959 				    nowait);
960 				releasef(sfv->sfv_fd);
961 				*count += cnt;
962 				if (error)
963 					return (error);
964 				sfv++;
965 				continue;
966 			}
967 
968 			while (sfv_len > 0) {
969 				size_t	iov_len;
970 
971 				iov_len = MIN(size, sfv_len);
972 
973 				if (vp->v_type == VSOCK) {
974 					dmp = allocb(iov_len + extra, BPRI_HI);
975 					if (dmp == NULL) {
976 						VOP_RWUNLOCK(readvp,
977 						    V_WRITELOCK_FALSE, NULL);
978 						releasef(sfv->sfv_fd);
979 						return (ENOMEM);
980 					}
981 					dmp->b_wptr = dmp->b_rptr =
982 					    dmp->b_rptr + wroff;
983 					ptr = (caddr_t)dmp->b_rptr;
984 				} else {
985 					ptr = buf;
986 				}
987 
988 				aiov.iov_base = ptr;
989 				aiov.iov_len = iov_len;
990 				auio.uio_loffset = sfv_off;
991 				auio.uio_iov = &aiov;
992 				auio.uio_iovcnt = 1;
993 				auio.uio_resid = iov_len;
994 				auio.uio_segflg = UIO_SYSSPACE;
995 				auio.uio_llimit = MAXOFFSET_T;
996 				auio.uio_fmode = ffp->f_flag;
997 				ioflag = auio.uio_fmode &
998 				    (FAPPEND|FSYNC|FDSYNC|FRSYNC);
999 
1000 				/*
1001 				 * If read sync is not asked for,
1002 				 * filter sync flags
1003 				 */
1004 				if ((ioflag & FRSYNC) == 0)
1005 					ioflag &= ~(FSYNC|FDSYNC);
1006 				error = VOP_READ(readvp, &auio, ioflag,
1007 				    fp->f_cred, NULL);
1008 				if (error != 0) {
1009 					/*
1010 					 * If we were reading a pipe (currently
1011 					 * not implemented), we may now lose
1012 					 * data.
1013 					 */
1014 					if (vp->v_type == VSOCK)
1015 						freeb(dmp);
1016 					else
1017 						kmem_free(buf, size);
1018 					VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE,
1019 					    NULL);
1020 					releasef(sfv->sfv_fd);
1021 					return (error);
1022 				}
1023 
1024 				/*
1025 				 * Check how much data was really read.
1026 				 * Decrement the 'len' and increment the
1027 				 * 'off' appropriately.
1028 				 */
1029 				cnt = iov_len - auio.uio_resid;
1030 				if (cnt == 0) {
1031 					if (vp->v_type == VSOCK)
1032 						freeb(dmp);
1033 					else
1034 						kmem_free(buf, size);
1035 					VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE,
1036 					    NULL);
1037 					releasef(sfv->sfv_fd);
1038 					return (EINVAL);
1039 				}
1040 				sfv_len -= cnt;
1041 				sfv_off += cnt;
1042 
1043 				if (vp->v_type == VSOCK) {
1044 					dmp->b_wptr = dmp->b_rptr + cnt;
1045 
1046 					error = socket_sendmblk(VTOSO(vp),
1047 					    &msg, fflag, CRED(), &dmp);
1048 
1049 					if (error != 0) {
1050 						if (dmp != NULL)
1051 							freeb(dmp);
1052 						VOP_RWUNLOCK(readvp,
1053 						    V_WRITELOCK_FALSE, NULL);
1054 						releasef(sfv->sfv_fd);
1055 						return (error);
1056 					}
1057 
1058 					ttolwp(curthread)->lwp_ru.ioch +=
1059 					    (ulong_t)cnt;
1060 					*count += cnt;
1061 				} else {
1062 
1063 					aiov.iov_base = ptr;
1064 					aiov.iov_len = cnt;
1065 					auio.uio_loffset = *fileoff;
1066 					auio.uio_resid = cnt;
1067 					auio.uio_iov = &aiov;
1068 					auio.uio_iovcnt = 1;
1069 					auio.uio_segflg = UIO_SYSSPACE;
1070 					auio.uio_llimit = curproc->p_fsz_ctl;
1071 					auio.uio_fmode = fflag;
1072 					ioflag = auio.uio_fmode &
1073 					    (FAPPEND|FSYNC|FDSYNC|FRSYNC);
1074 					error = VOP_WRITE(vp, &auio, ioflag,
1075 					    fp->f_cred, NULL);
1076 
1077 					/*
1078 					 * Check how much data was written.
1079 					 * Increment the 'len' and decrement the
1080 					 * 'off' if all the data was not
1081 					 * written.
1082 					 */
1083 					cnt -= auio.uio_resid;
1084 					sfv_len += auio.uio_resid;
1085 					sfv_off -= auio.uio_resid;
1086 					ttolwp(curthread)->lwp_ru.ioch +=
1087 					    (ulong_t)cnt;
1088 					*fileoff += cnt;
1089 					*count += cnt;
1090 					if (error != 0) {
1091 						kmem_free(buf, size);
1092 						VOP_RWUNLOCK(readvp,
1093 						    V_WRITELOCK_FALSE, NULL);
1094 						releasef(sfv->sfv_fd);
1095 						return (error);
1096 					}
1097 				}
1098 			}
1099 			if (buf) {
1100 				kmem_free(buf, size);
1101 				buf = NULL;
1102 			}
1103 			VOP_RWUNLOCK(readvp, V_WRITELOCK_FALSE, NULL);
1104 			releasef(sfv->sfv_fd);
1105 		}
1106 		sfv++;
1107 	}
1108 	return (0);
1109 }
1110 
1111 ssize_t
1112 sendfilev(int opcode, int fildes, const struct sendfilevec *vec, int sfvcnt,
1113     size_t *xferred)
1114 {
1115 	int error = 0;
1116 	int first_vector_error = 0;
1117 	file_t *fp;
1118 	struct vnode *vp;
1119 	struct sonode *so;
1120 	u_offset_t fileoff;
1121 	int copy_cnt;
1122 	const struct sendfilevec *copy_vec;
1123 	struct sendfilevec sfv[SEND_MAX_CHUNK];
1124 	ssize_t count = 0;
1125 #ifdef _SYSCALL32_IMPL
1126 	struct ksendfilevec32 sfv32[SEND_MAX_CHUNK];
1127 #endif
1128 	ssize_t total_size;
1129 	int i;
1130 	boolean_t is_sock = B_FALSE;
1131 	int maxblk = 0;
1132 
1133 	if (sfvcnt <= 0)
1134 		return (set_errno(EINVAL));
1135 
1136 	if ((fp = getf(fildes)) == NULL)
1137 		return (set_errno(EBADF));
1138 
1139 	if (((fp->f_flag) & FWRITE) == 0) {
1140 		error = EBADF;
1141 		goto err;
1142 	}
1143 
1144 	fileoff = fp->f_offset;
1145 	vp = fp->f_vnode;
1146 
1147 	switch (vp->v_type) {
1148 	case VSOCK:
1149 		so = VTOSO(vp);
1150 		is_sock = B_TRUE;
1151 		if (SOCK_IS_NONSTR(so)) {
1152 			maxblk = so->so_proto_props.sopp_maxblk;
1153 		} else {
1154 			maxblk = (int)vp->v_stream->sd_maxblk;
1155 		}
1156 		break;
1157 	case VREG:
1158 		break;
1159 	default:
1160 		error = EINVAL;
1161 		goto err;
1162 	}
1163 
1164 	switch (opcode) {
1165 	case SENDFILEV :
1166 		break;
1167 #if defined(_SYSCALL32_IMPL) || defined(_ILP32)
1168 	case SENDFILEV64 :
1169 		return (sendvec64(fp, (struct ksendfilevec64 *)vec, sfvcnt,
1170 		    (size32_t *)xferred, fildes));
1171 #endif
1172 	default :
1173 		error = ENOSYS;
1174 		break;
1175 	}
1176 
1177 	(void) VOP_RWLOCK(vp, V_WRITELOCK_TRUE, NULL);
1178 	copy_vec = vec;
1179 
1180 	do {
1181 		total_size = 0;
1182 		copy_cnt = MIN(sfvcnt, SEND_MAX_CHUNK);
1183 #ifdef _SYSCALL32_IMPL
1184 		/* 32-bit callers need to have their iovec expanded. */
1185 		if (get_udatamodel() == DATAMODEL_ILP32) {
1186 			if (copyin(copy_vec, sfv32,
1187 			    copy_cnt * sizeof (ksendfilevec32_t))) {
1188 				error = EFAULT;
1189 				break;
1190 			}
1191 
1192 			for (i = 0; i < copy_cnt; i++) {
1193 				sfv[i].sfv_fd = sfv32[i].sfv_fd;
1194 				sfv[i].sfv_off =
1195 				    (off_t)(uint32_t)sfv32[i].sfv_off;
1196 				sfv[i].sfv_len = (size_t)sfv32[i].sfv_len;
1197 				total_size += sfv[i].sfv_len;
1198 				sfv[i].sfv_flag = sfv32[i].sfv_flag;
1199 				/*
1200 				 * Individual elements of the vector must not
1201 				 * wrap or overflow, as later math is signed.
1202 				 * Equally total_size needs to be checked after
1203 				 * each vector is added in, to be sure that
1204 				 * rogue values haven't overflowed the counter.
1205 				 */
1206 				if (((ssize32_t)sfv[i].sfv_len < 0) ||
1207 				    ((ssize32_t)total_size < 0)) {
1208 					/*
1209 					 * Truncate the vector to send data
1210 					 * described by elements before the
1211 					 * error.
1212 					 */
1213 					copy_cnt = i;
1214 					first_vector_error = EINVAL;
1215 					/* total_size can't be trusted */
1216 					if ((ssize32_t)total_size < 0)
1217 						error = EINVAL;
1218 					break;
1219 				}
1220 			}
1221 			/* Nothing to do, process errors */
1222 			if (copy_cnt == 0)
1223 				break;
1224 
1225 		} else {
1226 #endif
1227 			if (copyin(copy_vec, sfv,
1228 			    copy_cnt * sizeof (sendfilevec_t))) {
1229 				error = EFAULT;
1230 				break;
1231 			}
1232 
1233 			for (i = 0; i < copy_cnt; i++) {
1234 				total_size += sfv[i].sfv_len;
1235 				/*
1236 				 * Individual elements of the vector must not
1237 				 * wrap or overflow, as later math is signed.
1238 				 * Equally total_size needs to be checked after
1239 				 * each vector is added in, to be sure that
1240 				 * rogue values haven't overflowed the counter.
1241 				 */
1242 				if (((ssize_t)sfv[i].sfv_len < 0) ||
1243 				    (total_size < 0)) {
1244 					/*
1245 					 * Truncate the vector to send data
1246 					 * described by elements before the
1247 					 * error.
1248 					 */
1249 					copy_cnt = i;
1250 					first_vector_error = EINVAL;
1251 					/* total_size can't be trusted */
1252 					if (total_size < 0)
1253 						error = EINVAL;
1254 					break;
1255 				}
1256 			}
1257 			/* Nothing to do, process errors */
1258 			if (copy_cnt == 0)
1259 				break;
1260 #ifdef _SYSCALL32_IMPL
1261 		}
1262 #endif
1263 
1264 		/*
1265 		 * The task between deciding to use sendvec_small_chunk
1266 		 * and sendvec_chunk is dependant on multiple things:
1267 		 *
1268 		 * i) latency is important for smaller files. So if the
1269 		 * data is smaller than 'tcp_slow_start_initial' times
1270 		 * maxblk, then use sendvec_small_chunk which creates
1271 		 * maxblk size mblks and chains them together and sends
1272 		 * them to TCP in one shot. It also leaves 'wroff' size
1273 		 * space for the headers in each mblk.
1274 		 *
1275 		 * ii) for total size bigger than 'tcp_slow_start_initial'
1276 		 * time maxblk, its probably real file data which is
1277 		 * dominating. So its better to use sendvec_chunk because
1278 		 * performance goes to dog if we don't do pagesize reads.
1279 		 * sendvec_chunk will do pagesize reads and write them
1280 		 * in pagesize mblks to TCP.
1281 		 *
1282 		 * Side Notes: A write to file has not been optimized.
1283 		 * Future zero copy code will plugin into sendvec_chunk
1284 		 * only because doing zero copy for files smaller then
1285 		 * pagesize is useless.
1286 		 *
1287 		 * Note, if socket has NL7C enabled then call NL7C's
1288 		 * senfilev() function to consume the sfv[].
1289 		 */
1290 		if (is_sock) {
1291 			if (!SOCK_IS_NONSTR(so) &&
1292 			    _SOTOTPI(so)->sti_nl7c_flags != 0) {
1293 				error = nl7c_sendfilev(so, &fileoff,
1294 				    sfv, copy_cnt, &count);
1295 			} else if ((total_size <= (4 * maxblk)) &&
1296 			    error == 0) {
1297 				error = sendvec_small_chunk(fp,
1298 				    &fileoff, sfv, copy_cnt,
1299 				    total_size, maxblk, &count);
1300 			} else {
1301 				error = sendvec_chunk(fp, &fileoff,
1302 				    sfv, copy_cnt, &count);
1303 			}
1304 		} else {
1305 			ASSERT(vp->v_type == VREG);
1306 			error = sendvec_chunk(fp, &fileoff, sfv, copy_cnt,
1307 			    &count);
1308 		}
1309 
1310 
1311 #ifdef _SYSCALL32_IMPL
1312 	if (get_udatamodel() == DATAMODEL_ILP32)
1313 		copy_vec = (const struct sendfilevec *)((char *)copy_vec +
1314 		    (copy_cnt * sizeof (ksendfilevec32_t)));
1315 	else
1316 #endif
1317 		copy_vec += copy_cnt;
1318 		sfvcnt -= copy_cnt;
1319 
1320 	/* Process all vector members up to first error */
1321 	} while ((sfvcnt > 0) && first_vector_error == 0 && error == 0);
1322 
1323 	if (vp->v_type == VREG)
1324 		fp->f_offset += count;
1325 
1326 	VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
1327 
1328 #ifdef _SYSCALL32_IMPL
1329 	if (get_udatamodel() == DATAMODEL_ILP32) {
1330 		ssize32_t count32 = (ssize32_t)count;
1331 		if (copyout(&count32, xferred, sizeof (count32)))
1332 			error = EFAULT;
1333 		releasef(fildes);
1334 		if (error != 0)
1335 			return (set_errno(error));
1336 		if (first_vector_error != 0)
1337 			return (set_errno(first_vector_error));
1338 		return (count32);
1339 	}
1340 #endif
1341 	if (copyout(&count, xferred, sizeof (count)))
1342 		error = EFAULT;
1343 	releasef(fildes);
1344 	if (error != 0)
1345 		return (set_errno(error));
1346 	if (first_vector_error != 0)
1347 		return (set_errno(first_vector_error));
1348 	return (count);
1349 err:
1350 	ASSERT(error != 0);
1351 	releasef(fildes);
1352 	return (set_errno(error));
1353 }
1354