]> git.saurik.com Git - apple/xnu.git/blob - bsd/nfs/nfs_bio.c
0e7c29ea9463da0761c2bc9595221d3fc5bf1117
[apple/xnu.git] / bsd / nfs / nfs_bio.c
1 /*
2 * Copyright (c) 2000-2019 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
29 /*
30 * Copyright (c) 1989, 1993
31 * The Regents of the University of California. All rights reserved.
32 *
33 * This code is derived from software contributed to Berkeley by
34 * Rick Macklem at The University of Guelph.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 3. All advertising materials mentioning features or use of this software
45 * must display the following acknowledgement:
46 * This product includes software developed by the University of
47 * California, Berkeley and its contributors.
48 * 4. Neither the name of the University nor the names of its contributors
49 * may be used to endorse or promote products derived from this software
50 * without specific prior written permission.
51 *
52 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62 * SUCH DAMAGE.
63 *
64 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95
65 * FreeBSD-Id: nfs_bio.c,v 1.44 1997/09/10 19:52:25 phk Exp $
66 */
67
68 #include <nfs/nfs_conf.h>
69 #if CONFIG_NFS_CLIENT
70
71 #include <sys/param.h>
72 #include <sys/systm.h>
73 #include <sys/resourcevar.h>
74 #include <sys/signalvar.h>
75 #include <sys/proc_internal.h>
76 #include <sys/kauth.h>
77 #include <sys/malloc.h>
78 #include <sys/vnode.h>
79 #include <sys/dirent.h>
80 #include <sys/mount_internal.h>
81 #include <sys/kernel.h>
82 #include <sys/ubc_internal.h>
83 #include <sys/uio_internal.h>
84 #include <sys/kpi_mbuf.h>
85
86 #include <sys/vm.h>
87 #include <sys/vmparam.h>
88
89 #include <sys/time.h>
90 #include <kern/clock.h>
91 #include <libkern/OSAtomic.h>
92 #include <kern/kalloc.h>
93 #include <kern/thread_call.h>
94
95 #include <nfs/rpcv2.h>
96 #include <nfs/nfsproto.h>
97 #include <nfs/nfs.h>
98 #include <nfs/nfs_gss.h>
99 #include <nfs/nfsmount.h>
100 #include <nfs/nfsnode.h>
101 #include <sys/buf_internal.h>
102 #include <libkern/OSAtomic.h>
103 #include <os/refcnt.h>
104
105 #define NFS_BIO_DBG(...) NFS_DBG(NFS_FAC_BIO, 7, ## __VA_ARGS__)
106
107 kern_return_t thread_terminate(thread_t); /* XXX */
108
109 #define NFSBUFHASH(np, lbn) \
110 (&nfsbufhashtbl[((long)(np) / sizeof(*(np)) + (int)(lbn)) & nfsbufhash])
111 LIST_HEAD(nfsbufhashhead, nfsbuf) * nfsbufhashtbl;
112 struct nfsbuffreehead nfsbuffree, nfsbuffreemeta, nfsbufdelwri;
113 u_long nfsbufhash;
114 int nfsbufcnt, nfsbufmin, nfsbufmax, nfsbufmetacnt, nfsbufmetamax;
115 int nfsbuffreecnt, nfsbuffreemetacnt, nfsbufdelwricnt, nfsneedbuffer;
116 int nfs_nbdwrite;
117 int nfs_buf_timer_on = 0;
118 thread_t nfsbufdelwrithd = NULL;
119
120 ZONE_DECLARE(nfsbuf_zone, "NFS bio", sizeof(struct nfsbuf), ZC_NONE);
121
122 lck_grp_t *nfs_buf_lck_grp;
123 lck_mtx_t *nfs_buf_mutex;
124
125 #define NFSBUF_FREE_PERIOD 30 /* seconds */
126 #define NFSBUF_LRU_STALE 120
127 #define NFSBUF_META_STALE 240
128
129 /* number of nfsbufs nfs_buf_freeup() should attempt to free from nfsbuffree list */
130 #define LRU_TO_FREEUP 6
131 /* number of nfsbufs nfs_buf_freeup() should attempt to free from nfsbuffreemeta list */
132 #define META_TO_FREEUP 3
133 /* total number of nfsbufs nfs_buf_freeup() should attempt to free */
134 #define TOTAL_TO_FREEUP (LRU_TO_FREEUP+META_TO_FREEUP)
135 /* fraction of nfsbufs nfs_buf_freeup() should attempt to free from nfsbuffree list when called from timer */
136 #define LRU_FREEUP_FRAC_ON_TIMER 8
137 /* fraction of nfsbufs nfs_buf_freeup() should attempt to free from nfsbuffreemeta list when called from timer */
138 #define META_FREEUP_FRAC_ON_TIMER 16
139 /* fraction of total nfsbufs that nfsbuffreecnt should exceed before bothering to call nfs_buf_freeup() */
140 #define LRU_FREEUP_MIN_FRAC 4
141 /* fraction of total nfsbufs that nfsbuffreemetacnt should exceed before bothering to call nfs_buf_freeup() */
142 #define META_FREEUP_MIN_FRAC 2
143
144 #define NFS_ROUND_BLOCK(p, blksize) ((((uint64_t)(p) + blksize - 1) & ~((uint64_t)blksize - 1)) / blksize)
145
146 #define NFS_BUF_FREEUP() \
147 do { \
148 /* only call nfs_buf_freeup() if it has work to do: */ \
149 if (((nfsbuffreecnt > nfsbufcnt/LRU_FREEUP_MIN_FRAC) || \
150 (nfsbuffreemetacnt > nfsbufcnt/META_FREEUP_MIN_FRAC)) && \
151 ((nfsbufcnt - TOTAL_TO_FREEUP) > nfsbufmin)) \
152 nfs_buf_freeup(0); \
153 } while (0)
154
155 void
156 nfs_buf_pgs_get_page_mask(nfsbufpgs *nfsbp, off_t page)
157 {
158 off_t page_pos = page / NBPGS_ELEMENT_PAGES;
159 off_t max_page = NBPGS_STRUCT_SIZE * 8;
160 NBPGS_ERASE(nfsbp);
161
162 if (page >= max_page) {
163 nfs_buf_pgs_bit_not(nfsbp);
164 return;
165 }
166
167 NBPGS_SET(nfsbp, page);
168 nfsbp->pages[page_pos]--;
169 for (off_t i = page_pos - 1; i >= 0; i--) {
170 nfsbp->pages[i] = ~0;
171 }
172 }
173
174 void
175 nfs_buf_pgs_bit_not(nfsbufpgs *nfsbp)
176 {
177 for (uint32_t i = 0; i < NBPGS_ELEMENTS; i++) {
178 nfsbp->pages[i] = ~nfsbp->pages[i];
179 }
180 }
181
182 void
183 nfs_buf_pgs_bit_and(nfsbufpgs *nfsbp_src1, nfsbufpgs *nfsbp_src2, nfsbufpgs *nfsbp_dst)
184 {
185 for (uint32_t i = 0; i < NBPGS_ELEMENTS; i++) {
186 nfsbp_dst->pages[i] = nfsbp_src1->pages[i] & nfsbp_src2->pages[i];
187 }
188 }
189
190 void
191 nfs_buf_pgs_set_pages_between(nfsbufpgs *nfsbp, off_t firstpg, off_t lastpg)
192 {
193 nfsbufpgs pagemaskfirst, pagemasklast;
194
195 nfs_buf_pgs_get_page_mask(&pagemasklast, lastpg);
196 nfs_buf_pgs_get_page_mask(&pagemaskfirst, firstpg);
197 nfs_buf_pgs_bit_not(&pagemaskfirst);
198 nfs_buf_pgs_bit_and(&pagemaskfirst, &pagemasklast, nfsbp);
199 }
200
201 int
202 nfs_buf_pgs_is_set(nfsbufpgs *nfsbp)
203 {
204 for (uint32_t i = 0; i < NBPGS_ELEMENTS; i++) {
205 if (nfsbp->pages[i] != 0) {
206 return 1;
207 }
208 }
209 return 0;
210 }
211
212 /*
213 * Initialize nfsbuf lists
214 */
215 void
216 nfs_nbinit(void)
217 {
218 nfs_buf_lck_grp = lck_grp_alloc_init("nfs_buf", LCK_GRP_ATTR_NULL);
219 nfs_buf_mutex = lck_mtx_alloc_init(nfs_buf_lck_grp, LCK_ATTR_NULL);
220
221 nfsbufcnt = nfsbufmetacnt =
222 nfsbuffreecnt = nfsbuffreemetacnt = nfsbufdelwricnt = 0;
223 nfsbufmin = 128;
224 /* size nfsbufmax to cover at most half sane_size (w/default buf size) */
225 nfsbufmax = (int)(sane_size >> PAGE_SHIFT) / (2 * (NFS_RWSIZE >> PAGE_SHIFT));
226 nfsbufmetamax = nfsbufmax / 4;
227 nfsneedbuffer = 0;
228 nfs_nbdwrite = 0;
229
230 nfsbufhashtbl = hashinit(nfsbufmax / 4, M_NFSBIO, &nfsbufhash);
231 TAILQ_INIT(&nfsbuffree);
232 TAILQ_INIT(&nfsbuffreemeta);
233 TAILQ_INIT(&nfsbufdelwri);
234 }
235
236 /*
237 * Check periodically for stale/unused nfs bufs
238 */
239 void
240 nfs_buf_timer(__unused void *param0, __unused void *param1)
241 {
242 nfs_buf_freeup(1);
243
244 lck_mtx_lock(nfs_buf_mutex);
245 if (nfsbufcnt <= nfsbufmin) {
246 nfs_buf_timer_on = 0;
247 lck_mtx_unlock(nfs_buf_mutex);
248 return;
249 }
250 lck_mtx_unlock(nfs_buf_mutex);
251
252 nfs_interval_timer_start(nfs_buf_timer_call,
253 NFSBUF_FREE_PERIOD * 1000);
254 }
255
256 /*
257 * try to free up some excess, unused nfsbufs
258 */
259 void
260 nfs_buf_freeup(int timer)
261 {
262 struct nfsbuf *fbp;
263 struct timeval now;
264 int count;
265 struct nfsbuffreehead nfsbuffreeup;
266
267 TAILQ_INIT(&nfsbuffreeup);
268
269 lck_mtx_lock(nfs_buf_mutex);
270
271 microuptime(&now);
272
273 FSDBG(320, nfsbufcnt, nfsbuffreecnt, nfsbuffreemetacnt, 0);
274
275 count = timer ? nfsbuffreecnt / LRU_FREEUP_FRAC_ON_TIMER : LRU_TO_FREEUP;
276 while ((nfsbufcnt > nfsbufmin) && (count-- > 0)) {
277 fbp = TAILQ_FIRST(&nfsbuffree);
278 if (!fbp) {
279 break;
280 }
281 if (os_ref_get_count(&fbp->nb_refs) > 1) {
282 break;
283 }
284 if (NBUFSTAMPVALID(fbp) &&
285 (fbp->nb_timestamp + (2 * NFSBUF_LRU_STALE)) > now.tv_sec) {
286 break;
287 }
288 nfs_buf_remfree(fbp);
289 /* disassociate buffer from any nfsnode */
290 if (fbp->nb_np) {
291 if (fbp->nb_vnbufs.le_next != NFSNOLIST) {
292 LIST_REMOVE(fbp, nb_vnbufs);
293 fbp->nb_vnbufs.le_next = NFSNOLIST;
294 }
295 fbp->nb_np = NULL;
296 }
297 LIST_REMOVE(fbp, nb_hash);
298 TAILQ_INSERT_TAIL(&nfsbuffreeup, fbp, nb_free);
299 nfsbufcnt--;
300 }
301
302 count = timer ? nfsbuffreemetacnt / META_FREEUP_FRAC_ON_TIMER : META_TO_FREEUP;
303 while ((nfsbufcnt > nfsbufmin) && (count-- > 0)) {
304 fbp = TAILQ_FIRST(&nfsbuffreemeta);
305 if (!fbp) {
306 break;
307 }
308 if (os_ref_get_count(&fbp->nb_refs) > 1) {
309 break;
310 }
311 if (NBUFSTAMPVALID(fbp) &&
312 (fbp->nb_timestamp + (2 * NFSBUF_META_STALE)) > now.tv_sec) {
313 break;
314 }
315 nfs_buf_remfree(fbp);
316 /* disassociate buffer from any nfsnode */
317 if (fbp->nb_np) {
318 if (fbp->nb_vnbufs.le_next != NFSNOLIST) {
319 LIST_REMOVE(fbp, nb_vnbufs);
320 fbp->nb_vnbufs.le_next = NFSNOLIST;
321 }
322 fbp->nb_np = NULL;
323 }
324 LIST_REMOVE(fbp, nb_hash);
325 TAILQ_INSERT_TAIL(&nfsbuffreeup, fbp, nb_free);
326 nfsbufcnt--;
327 nfsbufmetacnt--;
328 }
329
330 FSDBG(320, nfsbufcnt, nfsbuffreecnt, nfsbuffreemetacnt, 0);
331 NFSBUFCNTCHK();
332
333 lck_mtx_unlock(nfs_buf_mutex);
334
335 while ((fbp = TAILQ_FIRST(&nfsbuffreeup))) {
336 TAILQ_REMOVE(&nfsbuffreeup, fbp, nb_free);
337 /* nuke any creds */
338 if (IS_VALID_CRED(fbp->nb_rcred)) {
339 kauth_cred_unref(&fbp->nb_rcred);
340 }
341 if (IS_VALID_CRED(fbp->nb_wcred)) {
342 kauth_cred_unref(&fbp->nb_wcred);
343 }
344 /* if buf was NB_META, dump buffer */
345 if (ISSET(fbp->nb_flags, NB_META) && fbp->nb_data) {
346 kheap_free(KHEAP_DATA_BUFFERS, fbp->nb_data, fbp->nb_bufsize);
347 }
348 NFS_ZFREE(nfsbuf_zone, fbp);
349 }
350 }
351
352 /*
353 * remove a buffer from the freelist
354 * (must be called with nfs_buf_mutex held)
355 */
356 void
357 nfs_buf_remfree(struct nfsbuf *bp)
358 {
359 if (bp->nb_free.tqe_next == NFSNOLIST) {
360 panic("nfsbuf not on free list");
361 }
362 if (ISSET(bp->nb_flags, NB_DELWRI)) {
363 nfsbufdelwricnt--;
364 TAILQ_REMOVE(&nfsbufdelwri, bp, nb_free);
365 } else if (ISSET(bp->nb_flags, NB_META)) {
366 nfsbuffreemetacnt--;
367 TAILQ_REMOVE(&nfsbuffreemeta, bp, nb_free);
368 } else {
369 nfsbuffreecnt--;
370 TAILQ_REMOVE(&nfsbuffree, bp, nb_free);
371 }
372 bp->nb_free.tqe_next = NFSNOLIST;
373 NFSBUFCNTCHK();
374 }
375
376 /*
377 * check for existence of nfsbuf in cache
378 */
379 boolean_t
380 nfs_buf_is_incore(nfsnode_t np, daddr64_t blkno)
381 {
382 boolean_t rv;
383 lck_mtx_lock(nfs_buf_mutex);
384 if (nfs_buf_incore(np, blkno)) {
385 rv = TRUE;
386 } else {
387 rv = FALSE;
388 }
389 lck_mtx_unlock(nfs_buf_mutex);
390 return rv;
391 }
392
393 /*
394 * return incore buffer (must be called with nfs_buf_mutex held)
395 */
396 struct nfsbuf *
397 nfs_buf_incore(nfsnode_t np, daddr64_t blkno)
398 {
399 /* Search hash chain */
400 struct nfsbuf * bp = NFSBUFHASH(np, blkno)->lh_first;
401 for (; bp != NULL; bp = bp->nb_hash.le_next) {
402 if ((bp->nb_lblkno == blkno) && (bp->nb_np == np)) {
403 if (!ISSET(bp->nb_flags, NB_INVAL)) {
404 FSDBG(547, bp, blkno, bp->nb_flags, bp->nb_np);
405 return bp;
406 }
407 }
408 }
409 return NULL;
410 }
411
412 /*
413 * Check if it's OK to drop a page.
414 *
415 * Called by vnode_pager() on pageout request of non-dirty page.
416 * We need to make sure that it's not part of a delayed write.
417 * If it is, we can't let the VM drop it because we may need it
418 * later when/if we need to write the data (again).
419 */
420 int
421 nfs_buf_page_inval(vnode_t vp, off_t offset)
422 {
423 struct nfsmount *nmp = VTONMP(vp);
424 struct nfsbuf *bp;
425 int error = 0;
426
427 if (nfs_mount_gone(nmp)) {
428 return ENXIO;
429 }
430
431 lck_mtx_lock(nfs_buf_mutex);
432 bp = nfs_buf_incore(VTONFS(vp), (daddr64_t)(offset / nmp->nm_biosize));
433 if (!bp) {
434 goto out;
435 }
436 FSDBG(325, bp, bp->nb_flags, bp->nb_dirtyoff, bp->nb_dirtyend);
437 if (ISSET(bp->nb_lflags, NBL_BUSY)) {
438 error = EBUSY;
439 goto out;
440 }
441 /*
442 * If there's a dirty range in the buffer, check to
443 * see if this page intersects with the dirty range.
444 * If it does, we can't let the pager drop the page.
445 */
446 if (bp->nb_dirtyend > 0) {
447 off_t start = offset - NBOFF(bp);
448 if ((bp->nb_dirtyend > start) &&
449 (bp->nb_dirtyoff < (start + PAGE_SIZE))) {
450 /*
451 * Before returning the bad news, move the
452 * buffer to the start of the delwri list and
453 * give the list a push to try to flush the
454 * buffer out.
455 */
456 error = EBUSY;
457 nfs_buf_remfree(bp);
458 TAILQ_INSERT_HEAD(&nfsbufdelwri, bp, nb_free);
459 nfsbufdelwricnt++;
460 nfs_buf_delwri_push(1);
461 }
462 }
463 out:
464 lck_mtx_unlock(nfs_buf_mutex);
465 return error;
466 }
467
468 /*
469 * set up the UPL for a buffer
470 * (must NOT be called with nfs_buf_mutex held)
471 */
472 int
473 nfs_buf_upl_setup(struct nfsbuf *bp)
474 {
475 kern_return_t kret;
476 upl_t upl;
477 int upl_flags;
478
479 if (ISSET(bp->nb_flags, NB_PAGELIST)) {
480 return 0;
481 }
482
483 upl_flags = UPL_PRECIOUS;
484 if (!ISSET(bp->nb_flags, NB_READ)) {
485 /*
486 * We're doing a "write", so we intend to modify
487 * the pages we're gathering.
488 */
489 upl_flags |= UPL_WILL_MODIFY;
490 }
491 kret = ubc_create_upl_kernel(NFSTOV(bp->nb_np), NBOFF(bp), bp->nb_bufsize,
492 &upl, NULL, upl_flags, VM_KERN_MEMORY_FILE);
493 if (kret == KERN_INVALID_ARGUMENT) {
494 /* vm object probably doesn't exist any more */
495 bp->nb_pagelist = NULL;
496 return EINVAL;
497 }
498 if (kret != KERN_SUCCESS) {
499 printf("nfs_buf_upl_setup(): failed to get pagelist %d\n", kret);
500 bp->nb_pagelist = NULL;
501 return EIO;
502 }
503
504 FSDBG(538, bp, NBOFF(bp), bp->nb_bufsize, bp->nb_np);
505
506 bp->nb_pagelist = upl;
507 SET(bp->nb_flags, NB_PAGELIST);
508 return 0;
509 }
510
511 /*
512 * update buffer's valid/dirty info from UBC
513 * (must NOT be called with nfs_buf_mutex held)
514 */
515 void
516 nfs_buf_upl_check(struct nfsbuf *bp)
517 {
518 upl_page_info_t *pl;
519 off_t filesize, fileoffset;
520 int i, npages;
521
522 if (!ISSET(bp->nb_flags, NB_PAGELIST)) {
523 return;
524 }
525
526 npages = round_page_32(bp->nb_bufsize) / PAGE_SIZE;
527 filesize = ubc_getsize(NFSTOV(bp->nb_np));
528 fileoffset = NBOFF(bp);
529 if (fileoffset < filesize) {
530 SET(bp->nb_flags, NB_CACHE);
531 } else {
532 CLR(bp->nb_flags, NB_CACHE);
533 }
534
535 pl = ubc_upl_pageinfo(bp->nb_pagelist);
536 NBPGS_ERASE(&bp->nb_valid);
537 NBPGS_ERASE(&bp->nb_dirty);
538
539 for (i = 0; i < npages; i++, fileoffset += PAGE_SIZE_64) {
540 /* anything beyond the end of the file is not valid or dirty */
541 if (fileoffset >= filesize) {
542 break;
543 }
544 if (!upl_valid_page(pl, i)) {
545 CLR(bp->nb_flags, NB_CACHE);
546 continue;
547 }
548 NBPGVALID_SET(bp, i);
549 if (upl_dirty_page(pl, i)) {
550 NBPGDIRTY_SET(bp, i);
551 }
552 }
553 fileoffset = NBOFF(bp);
554 if (ISSET(bp->nb_flags, NB_CACHE)) {
555 bp->nb_validoff = 0;
556 bp->nb_validend = bp->nb_bufsize;
557 if (fileoffset + bp->nb_validend > filesize) {
558 bp->nb_validend = filesize - fileoffset;
559 }
560 } else {
561 bp->nb_validoff = bp->nb_validend = -1;
562 }
563 FSDBG(539, bp, fileoffset, bp->nb_valid, bp->nb_dirty);
564 FSDBG(539, bp->nb_validoff, bp->nb_validend, bp->nb_dirtyoff, bp->nb_dirtyend);
565 }
566
567 /*
568 * make sure that a buffer is mapped
569 * (must NOT be called with nfs_buf_mutex held)
570 */
571 int
572 nfs_buf_map(struct nfsbuf *bp)
573 {
574 kern_return_t kret;
575
576 if (bp->nb_data) {
577 return 0;
578 }
579 if (!ISSET(bp->nb_flags, NB_PAGELIST)) {
580 return EINVAL;
581 }
582
583 kret = ubc_upl_map(bp->nb_pagelist, (vm_offset_t *)&(bp->nb_data));
584 if (kret != KERN_SUCCESS) {
585 panic("nfs_buf_map: ubc_upl_map() failed with (%d)", kret);
586 }
587 if (bp->nb_data == 0) {
588 panic("ubc_upl_map mapped 0");
589 }
590 FSDBG(540, bp, bp->nb_flags, NBOFF(bp), bp->nb_data);
591 return 0;
592 }
593
594 /*
595 * normalize an nfsbuf's valid range
596 *
597 * the read/write code guarantees that we'll always have a valid
598 * region that is an integral number of pages. If either end
599 * of the valid range isn't page-aligned, it gets corrected
600 * here as we extend the valid range through all of the
601 * contiguous valid pages.
602 */
603 void
604 nfs_buf_normalize_valid_range(nfsnode_t np, struct nfsbuf *bp)
605 {
606 off_t pg, npg;
607 /* pull validoff back to start of contiguous valid page range */
608 pg = bp->nb_validoff / PAGE_SIZE;
609 while (pg >= 0 && NBPGVALID(bp, pg)) {
610 pg--;
611 }
612 bp->nb_validoff = (pg + 1) * PAGE_SIZE;
613 /* push validend forward to end of contiguous valid page range */
614 npg = bp->nb_bufsize / PAGE_SIZE;
615 pg = bp->nb_validend / PAGE_SIZE;
616 while (pg < npg && NBPGVALID(bp, pg)) {
617 pg++;
618 }
619 bp->nb_validend = pg * PAGE_SIZE;
620 /* clip to EOF */
621 if (NBOFF(bp) + bp->nb_validend > (off_t)np->n_size) {
622 bp->nb_validend = np->n_size % bp->nb_bufsize;
623 }
624 }
625
626 /*
627 * process some entries on the delayed write queue
628 * (must be called with nfs_buf_mutex held)
629 */
630 void
631 nfs_buf_delwri_service(void)
632 {
633 struct nfsbuf *bp;
634 nfsnode_t np;
635 int error, i = 0;
636
637 while (i < 8 && (bp = TAILQ_FIRST(&nfsbufdelwri)) != NULL) {
638 np = bp->nb_np;
639 nfs_buf_remfree(bp);
640 nfs_buf_refget(bp);
641 while ((error = nfs_buf_acquire(bp, 0, 0, 0)) == EAGAIN) {
642 ;
643 }
644 nfs_buf_refrele(bp);
645 if (error) {
646 break;
647 }
648 if (!bp->nb_np) {
649 /* buffer is no longer valid */
650 nfs_buf_drop(bp);
651 continue;
652 }
653 if (ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
654 nfs_buf_check_write_verifier(np, bp);
655 }
656 if (ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
657 /* put buffer at end of delwri list */
658 TAILQ_INSERT_TAIL(&nfsbufdelwri, bp, nb_free);
659 nfsbufdelwricnt++;
660 nfs_buf_drop(bp);
661 lck_mtx_unlock(nfs_buf_mutex);
662 nfs_flushcommits(np, 1);
663 } else {
664 SET(bp->nb_flags, NB_ASYNC);
665 lck_mtx_unlock(nfs_buf_mutex);
666 nfs_buf_write(bp);
667 }
668 i++;
669 lck_mtx_lock(nfs_buf_mutex);
670 }
671 }
672
673 /*
674 * thread to service the delayed write queue when asked
675 */
676 void
677 nfs_buf_delwri_thread(__unused void *arg, __unused wait_result_t wr)
678 {
679 struct timespec ts = { .tv_sec = 30, .tv_nsec = 0 };
680 int error = 0;
681
682 lck_mtx_lock(nfs_buf_mutex);
683 while (!error) {
684 nfs_buf_delwri_service();
685 error = msleep(&nfsbufdelwrithd, nfs_buf_mutex, 0, "nfsbufdelwri", &ts);
686 }
687 nfsbufdelwrithd = NULL;
688 lck_mtx_unlock(nfs_buf_mutex);
689 thread_terminate(nfsbufdelwrithd);
690 }
691
692 /*
693 * try to push out some delayed/uncommitted writes
694 * ("locked" indicates whether nfs_buf_mutex is already held)
695 */
696 void
697 nfs_buf_delwri_push(int locked)
698 {
699 if (TAILQ_EMPTY(&nfsbufdelwri)) {
700 return;
701 }
702 if (!locked) {
703 lck_mtx_lock(nfs_buf_mutex);
704 }
705 /* wake up the delayed write service thread */
706 if (nfsbufdelwrithd) {
707 wakeup(&nfsbufdelwrithd);
708 } else if (kernel_thread_start(nfs_buf_delwri_thread, NULL, &nfsbufdelwrithd) == KERN_SUCCESS) {
709 thread_deallocate(nfsbufdelwrithd);
710 }
711 /* otherwise, try to do some of the work ourselves */
712 if (!nfsbufdelwrithd) {
713 nfs_buf_delwri_service();
714 }
715 if (!locked) {
716 lck_mtx_unlock(nfs_buf_mutex);
717 }
718 }
719
720 /*
721 * Get an nfs buffer.
722 *
723 * Returns errno on error, 0 otherwise.
724 * Any buffer is returned in *bpp.
725 *
726 * If NBLK_ONLYVALID is set, only return buffer if found in cache.
727 * If NBLK_NOWAIT is set, don't wait for the buffer if it's marked BUSY.
728 *
729 * Check for existence of buffer in cache.
730 * Or attempt to reuse a buffer from one of the free lists.
731 * Or allocate a new buffer if we haven't already hit max allocation.
732 * Or wait for a free buffer.
733 *
734 * If available buffer found, prepare it, and return it.
735 *
736 * If the calling process is interrupted by a signal for
737 * an interruptible mount point, return EINTR.
738 */
739 int
740 nfs_buf_get(
741 nfsnode_t np,
742 daddr64_t blkno,
743 uint32_t size,
744 thread_t thd,
745 int flags,
746 struct nfsbuf **bpp)
747 {
748 vnode_t vp = NFSTOV(np);
749 struct nfsmount *nmp = VTONMP(vp);
750 struct nfsbuf *bp;
751 uint32_t bufsize;
752 int slpflag = PCATCH;
753 int operation = (flags & NBLK_OPMASK);
754 int error = 0;
755 struct timespec ts;
756
757 FSDBG_TOP(541, np, blkno, size, flags);
758 *bpp = NULL;
759
760 bufsize = size;
761 if (bufsize > NFS_MAXBSIZE) {
762 panic("nfs_buf_get: buffer larger than NFS_MAXBSIZE requested");
763 }
764
765 if (nfs_mount_gone(nmp)) {
766 FSDBG_BOT(541, np, blkno, 0, ENXIO);
767 return ENXIO;
768 }
769
770 if (!UBCINFOEXISTS(vp)) {
771 operation = NBLK_META;
772 } else if (bufsize < (uint32_t)nmp->nm_biosize) {
773 /* reg files should always have biosize blocks */
774 bufsize = nmp->nm_biosize;
775 }
776
777 /* if NBLK_WRITE, check for too many delayed/uncommitted writes */
778 if ((operation == NBLK_WRITE) && (nfs_nbdwrite > NFS_A_LOT_OF_DELAYED_WRITES)) {
779 FSDBG_TOP(542, np, blkno, nfs_nbdwrite, NFS_A_LOT_OF_DELAYED_WRITES);
780
781 /* poke the delwri list */
782 nfs_buf_delwri_push(0);
783
784 /* sleep to let other threads run... */
785 tsleep(&nfs_nbdwrite, PCATCH, "nfs_nbdwrite", 1);
786 FSDBG_BOT(542, np, blkno, nfs_nbdwrite, NFS_A_LOT_OF_DELAYED_WRITES);
787 }
788
789 loop:
790 lck_mtx_lock(nfs_buf_mutex);
791
792 /* wait for any buffer invalidation/flushing to complete */
793 while (np->n_bflag & NBINVALINPROG) {
794 np->n_bflag |= NBINVALWANT;
795 ts.tv_sec = 2;
796 ts.tv_nsec = 0;
797 msleep(&np->n_bflag, nfs_buf_mutex, slpflag, "nfs_buf_get_invalwait", &ts);
798 if ((error = nfs_sigintr(VTONMP(vp), NULL, thd, 0))) {
799 lck_mtx_unlock(nfs_buf_mutex);
800 FSDBG_BOT(541, np, blkno, 0, error);
801 return error;
802 }
803 if (np->n_bflag & NBINVALINPROG) {
804 slpflag = 0;
805 }
806 }
807
808 /* check for existence of nfsbuf in cache */
809 if ((bp = nfs_buf_incore(np, blkno))) {
810 /* if busy, set wanted and wait */
811 if (ISSET(bp->nb_lflags, NBL_BUSY)) {
812 if (flags & NBLK_NOWAIT) {
813 lck_mtx_unlock(nfs_buf_mutex);
814 FSDBG_BOT(541, np, blkno, bp, 0xbcbcbcbc);
815 return 0;
816 }
817 FSDBG_TOP(543, np, blkno, bp, bp->nb_flags);
818 SET(bp->nb_lflags, NBL_WANTED);
819
820 ts.tv_sec = 2;
821 ts.tv_nsec = 0;
822 msleep(bp, nfs_buf_mutex, slpflag | (PRIBIO + 1) | PDROP,
823 "nfsbufget", (slpflag == PCATCH) ? NULL : &ts);
824 slpflag = 0;
825 FSDBG_BOT(543, np, blkno, bp, bp->nb_flags);
826 if ((error = nfs_sigintr(VTONMP(vp), NULL, thd, 0))) {
827 FSDBG_BOT(541, np, blkno, 0, error);
828 return error;
829 }
830 goto loop;
831 }
832 if (bp->nb_bufsize != bufsize) {
833 panic("nfsbuf size mismatch");
834 }
835 SET(bp->nb_lflags, NBL_BUSY);
836 SET(bp->nb_flags, NB_CACHE);
837 nfs_buf_remfree(bp);
838 /* additional paranoia: */
839 if (ISSET(bp->nb_flags, NB_PAGELIST)) {
840 panic("pagelist buffer was not busy");
841 }
842 goto buffer_setup;
843 }
844
845 if (flags & NBLK_ONLYVALID) {
846 lck_mtx_unlock(nfs_buf_mutex);
847 FSDBG_BOT(541, np, blkno, 0, 0x0000cace);
848 return 0;
849 }
850
851 /*
852 * where to get a free buffer:
853 * - if meta and maxmeta reached, must reuse meta
854 * - alloc new if we haven't reached min bufs
855 * - if free lists are NOT empty
856 * - if free list is stale, use it
857 * - else if freemeta list is stale, use it
858 * - else if max bufs allocated, use least-time-to-stale
859 * - alloc new if we haven't reached max allowed
860 * - start clearing out delwri list and try again
861 */
862
863 if ((operation == NBLK_META) && (nfsbufmetacnt >= nfsbufmetamax)) {
864 /* if we've hit max meta buffers, must reuse a meta buffer */
865 bp = TAILQ_FIRST(&nfsbuffreemeta);
866 } else if ((nfsbufcnt > nfsbufmin) &&
867 (!TAILQ_EMPTY(&nfsbuffree) || !TAILQ_EMPTY(&nfsbuffreemeta))) {
868 /* try to pull an nfsbuf off a free list */
869 struct nfsbuf *lrubp, *metabp;
870 struct timeval now;
871 microuptime(&now);
872
873 /* if the next LRU or META buffer is invalid or stale, use it */
874 lrubp = TAILQ_FIRST(&nfsbuffree);
875 if (lrubp && (!NBUFSTAMPVALID(lrubp) ||
876 ((lrubp->nb_timestamp + NFSBUF_LRU_STALE) < now.tv_sec))) {
877 bp = lrubp;
878 }
879 metabp = TAILQ_FIRST(&nfsbuffreemeta);
880 if (!bp && metabp && (!NBUFSTAMPVALID(metabp) ||
881 ((metabp->nb_timestamp + NFSBUF_META_STALE) < now.tv_sec))) {
882 bp = metabp;
883 }
884
885 if (!bp && (nfsbufcnt >= nfsbufmax)) {
886 /* we've already allocated all bufs, so */
887 /* choose the buffer that'll go stale first */
888 if (!metabp) {
889 bp = lrubp;
890 } else if (!lrubp) {
891 bp = metabp;
892 } else {
893 time_t lru_stale_time, meta_stale_time;
894 lru_stale_time = lrubp->nb_timestamp + NFSBUF_LRU_STALE;
895 meta_stale_time = metabp->nb_timestamp + NFSBUF_META_STALE;
896 if (lru_stale_time <= meta_stale_time) {
897 bp = lrubp;
898 } else {
899 bp = metabp;
900 }
901 }
902 }
903 }
904
905 if (bp) {
906 /* we have a buffer to reuse */
907 FSDBG(544, np, blkno, bp, bp->nb_flags);
908 nfs_buf_remfree(bp);
909 if (ISSET(bp->nb_flags, NB_DELWRI)) {
910 panic("nfs_buf_get: delwri");
911 }
912 SET(bp->nb_lflags, NBL_BUSY);
913 /* disassociate buffer from previous nfsnode */
914 if (bp->nb_np) {
915 if (bp->nb_vnbufs.le_next != NFSNOLIST) {
916 LIST_REMOVE(bp, nb_vnbufs);
917 bp->nb_vnbufs.le_next = NFSNOLIST;
918 }
919 bp->nb_np = NULL;
920 }
921 LIST_REMOVE(bp, nb_hash);
922 /* nuke any creds we're holding */
923 if (IS_VALID_CRED(bp->nb_rcred)) {
924 kauth_cred_unref(&bp->nb_rcred);
925 }
926 if (IS_VALID_CRED(bp->nb_wcred)) {
927 kauth_cred_unref(&bp->nb_wcred);
928 }
929 /* if buf will no longer be NB_META, dump old buffer */
930 if (operation == NBLK_META) {
931 if (!ISSET(bp->nb_flags, NB_META)) {
932 nfsbufmetacnt++;
933 }
934 } else if (ISSET(bp->nb_flags, NB_META)) {
935 if (bp->nb_data) {
936 kheap_free(KHEAP_DATA_BUFFERS, bp->nb_data, bp->nb_bufsize);
937 bp->nb_data = NULL;
938 }
939 nfsbufmetacnt--;
940 }
941 /* re-init buf fields */
942 bp->nb_error = 0;
943 bp->nb_validoff = bp->nb_validend = -1;
944 bp->nb_dirtyoff = bp->nb_dirtyend = 0;
945 NBPGS_ERASE(&bp->nb_valid);
946 NBPGS_ERASE(&bp->nb_dirty);
947 bp->nb_verf = 0;
948 } else {
949 /* no buffer to reuse */
950 if ((nfsbufcnt < nfsbufmax) &&
951 ((operation != NBLK_META) || (nfsbufmetacnt < nfsbufmetamax))) {
952 /* just alloc a new one */
953 bp = zalloc(nfsbuf_zone);
954 nfsbufcnt++;
955
956 /*
957 * If any excess bufs, make sure the timer
958 * is running to free them up later.
959 */
960 if (nfsbufcnt > nfsbufmin && !nfs_buf_timer_on) {
961 nfs_buf_timer_on = 1;
962 nfs_interval_timer_start(nfs_buf_timer_call,
963 NFSBUF_FREE_PERIOD * 1000);
964 }
965
966 if (operation == NBLK_META) {
967 nfsbufmetacnt++;
968 }
969 NFSBUFCNTCHK();
970 /* init nfsbuf */
971 bzero(bp, sizeof(*bp));
972 os_ref_init(&bp->nb_refs, NULL);
973
974 bp->nb_free.tqe_next = NFSNOLIST;
975 bp->nb_validoff = bp->nb_validend = -1;
976 FSDBG(545, np, blkno, bp, 0);
977 } else {
978 /* too many bufs... wait for buffers to free up */
979 FSDBG_TOP(546, np, blkno, nfsbufcnt, nfsbufmax);
980
981 /* poke the delwri list */
982 nfs_buf_delwri_push(1);
983
984 nfsneedbuffer = 1;
985 msleep(&nfsneedbuffer, nfs_buf_mutex, PCATCH | PDROP, "nfsbufget", NULL);
986 FSDBG_BOT(546, np, blkno, nfsbufcnt, nfsbufmax);
987 if ((error = nfs_sigintr(VTONMP(vp), NULL, thd, 0))) {
988 FSDBG_BOT(541, np, blkno, 0, error);
989 return error;
990 }
991 goto loop;
992 }
993 }
994
995 /* set up nfsbuf */
996 SET(bp->nb_lflags, NBL_BUSY);
997 bp->nb_flags = 0;
998 bp->nb_lblkno = blkno;
999 /* insert buf in hash */
1000 LIST_INSERT_HEAD(NFSBUFHASH(np, blkno), bp, nb_hash);
1001 /* associate buffer with new nfsnode */
1002 bp->nb_np = np;
1003 LIST_INSERT_HEAD(&np->n_cleanblkhd, bp, nb_vnbufs);
1004
1005 buffer_setup:
1006
1007 /* unlock hash */
1008 lck_mtx_unlock(nfs_buf_mutex);
1009
1010 switch (operation) {
1011 case NBLK_META:
1012 SET(bp->nb_flags, NB_META);
1013 if ((bp->nb_bufsize != bufsize) && bp->nb_data) {
1014 kheap_free(KHEAP_DATA_BUFFERS, bp->nb_data, bp->nb_bufsize);
1015 bp->nb_data = NULL;
1016 bp->nb_validoff = bp->nb_validend = -1;
1017 bp->nb_dirtyoff = bp->nb_dirtyend = 0;
1018 NBPGS_ERASE(&bp->nb_valid);
1019 NBPGS_ERASE(&bp->nb_dirty);
1020 CLR(bp->nb_flags, NB_CACHE);
1021 }
1022 if (!bp->nb_data) {
1023 bp->nb_data = kheap_alloc(KHEAP_DATA_BUFFERS,
1024 bufsize, Z_WAITOK);
1025 }
1026 if (!bp->nb_data) {
1027 /* Ack! couldn't allocate the data buffer! */
1028 /* clean up buffer and return error */
1029 lck_mtx_lock(nfs_buf_mutex);
1030 LIST_REMOVE(bp, nb_vnbufs);
1031 bp->nb_vnbufs.le_next = NFSNOLIST;
1032 bp->nb_np = NULL;
1033 /* invalidate usage timestamp to allow immediate freeing */
1034 NBUFSTAMPINVALIDATE(bp);
1035 if (bp->nb_free.tqe_next != NFSNOLIST) {
1036 panic("nfsbuf on freelist");
1037 }
1038 TAILQ_INSERT_HEAD(&nfsbuffree, bp, nb_free);
1039 nfsbuffreecnt++;
1040 lck_mtx_unlock(nfs_buf_mutex);
1041 FSDBG_BOT(541, np, blkno, 0xb00, ENOMEM);
1042 return ENOMEM;
1043 }
1044 bp->nb_bufsize = bufsize;
1045 break;
1046
1047 case NBLK_READ:
1048 case NBLK_WRITE:
1049 /*
1050 * Set or clear NB_READ now to let the UPL subsystem know
1051 * if we intend to modify the pages or not.
1052 */
1053 if (operation == NBLK_READ) {
1054 SET(bp->nb_flags, NB_READ);
1055 } else {
1056 CLR(bp->nb_flags, NB_READ);
1057 }
1058 if (bufsize < PAGE_SIZE) {
1059 bufsize = PAGE_SIZE;
1060 }
1061 bp->nb_bufsize = bufsize;
1062 bp->nb_validoff = bp->nb_validend = -1;
1063
1064 if (UBCINFOEXISTS(vp)) {
1065 /* set up upl */
1066 if (nfs_buf_upl_setup(bp)) {
1067 /* unable to create upl */
1068 /* vm object must no longer exist */
1069 /* clean up buffer and return error */
1070 lck_mtx_lock(nfs_buf_mutex);
1071 LIST_REMOVE(bp, nb_vnbufs);
1072 bp->nb_vnbufs.le_next = NFSNOLIST;
1073 bp->nb_np = NULL;
1074 /* invalidate usage timestamp to allow immediate freeing */
1075 NBUFSTAMPINVALIDATE(bp);
1076 if (bp->nb_free.tqe_next != NFSNOLIST) {
1077 panic("nfsbuf on freelist");
1078 }
1079 TAILQ_INSERT_HEAD(&nfsbuffree, bp, nb_free);
1080 nfsbuffreecnt++;
1081 lck_mtx_unlock(nfs_buf_mutex);
1082 FSDBG_BOT(541, np, blkno, 0x2bc, EIO);
1083 return EIO;
1084 }
1085 nfs_buf_upl_check(bp);
1086 }
1087 break;
1088
1089 default:
1090 panic("nfs_buf_get: %d unknown operation", operation);
1091 }
1092
1093 *bpp = bp;
1094
1095 FSDBG_BOT(541, np, blkno, bp, bp->nb_flags);
1096
1097 return 0;
1098 }
1099
1100 void
1101 nfs_buf_release(struct nfsbuf *bp, int freeup)
1102 {
1103 nfsnode_t np = bp->nb_np;
1104 vnode_t vp;
1105 struct timeval now;
1106 int wakeup_needbuffer, wakeup_buffer, wakeup_nbdwrite;
1107
1108 FSDBG_TOP(548, bp, NBOFF(bp), bp->nb_flags, bp->nb_data);
1109 FSDBG(548, bp->nb_validoff, bp->nb_validend, bp->nb_dirtyoff, bp->nb_dirtyend);
1110 FSDBG(548, bp->nb_valid, 0, bp->nb_dirty, 0);
1111
1112 vp = np ? NFSTOV(np) : NULL;
1113 if (vp && UBCINFOEXISTS(vp) && bp->nb_bufsize) {
1114 int upl_flags, rv;
1115 upl_t upl;
1116 uint32_t i;
1117
1118 if (!ISSET(bp->nb_flags, NB_PAGELIST) && !ISSET(bp->nb_flags, NB_INVAL)) {
1119 rv = nfs_buf_upl_setup(bp);
1120 if (rv) {
1121 printf("nfs_buf_release: upl create failed %d\n", rv);
1122 } else {
1123 nfs_buf_upl_check(bp);
1124 }
1125 }
1126 upl = bp->nb_pagelist;
1127 if (!upl) {
1128 goto pagelist_cleanup_done;
1129 }
1130 if (bp->nb_data) {
1131 if (ubc_upl_unmap(upl) != KERN_SUCCESS) {
1132 panic("ubc_upl_unmap failed");
1133 }
1134 bp->nb_data = NULL;
1135 }
1136 /*
1137 * Abort the pages on error or: if this is an invalid or
1138 * non-needcommit nocache buffer AND no pages are dirty.
1139 */
1140 if (ISSET(bp->nb_flags, NB_ERROR) || (!nfs_buf_pgs_is_set(&bp->nb_dirty) && (ISSET(bp->nb_flags, NB_INVAL) ||
1141 (ISSET(bp->nb_flags, NB_NOCACHE) && !ISSET(bp->nb_flags, (NB_NEEDCOMMIT | NB_DELWRI)))))) {
1142 if (ISSET(bp->nb_flags, (NB_READ | NB_INVAL | NB_NOCACHE))) {
1143 upl_flags = UPL_ABORT_DUMP_PAGES;
1144 } else {
1145 upl_flags = 0;
1146 }
1147 ubc_upl_abort(upl, upl_flags);
1148 goto pagelist_cleanup_done;
1149 }
1150 for (i = 0; i <= (bp->nb_bufsize - 1) / PAGE_SIZE; i++) {
1151 if (!NBPGVALID(bp, i)) {
1152 ubc_upl_abort_range(upl,
1153 i * PAGE_SIZE, PAGE_SIZE,
1154 UPL_ABORT_DUMP_PAGES |
1155 UPL_ABORT_FREE_ON_EMPTY);
1156 } else {
1157 if (NBPGDIRTY(bp, i)) {
1158 upl_flags = UPL_COMMIT_SET_DIRTY;
1159 } else {
1160 upl_flags = UPL_COMMIT_CLEAR_DIRTY;
1161 }
1162
1163 if (!ISSET(bp->nb_flags, (NB_NEEDCOMMIT | NB_DELWRI))) {
1164 upl_flags |= UPL_COMMIT_CLEAR_PRECIOUS;
1165 }
1166
1167 ubc_upl_commit_range(upl,
1168 i * PAGE_SIZE, PAGE_SIZE,
1169 upl_flags |
1170 UPL_COMMIT_INACTIVATE |
1171 UPL_COMMIT_FREE_ON_EMPTY);
1172 }
1173 }
1174 pagelist_cleanup_done:
1175 /* invalidate any pages past EOF */
1176 if (NBOFF(bp) + bp->nb_bufsize > (off_t)(np->n_size)) {
1177 off_t start, end;
1178 start = trunc_page_64(np->n_size) + PAGE_SIZE_64;
1179 end = trunc_page_64(NBOFF(bp) + bp->nb_bufsize);
1180 if (start < NBOFF(bp)) {
1181 start = NBOFF(bp);
1182 }
1183 if (end > start) {
1184 if ((rv = ubc_msync(vp, start, end, NULL, UBC_INVALIDATE))) {
1185 printf("nfs_buf_release(): ubc_msync failed!, error %d\n", rv);
1186 }
1187 }
1188 }
1189 CLR(bp->nb_flags, NB_PAGELIST);
1190 bp->nb_pagelist = NULL;
1191 }
1192
1193 lck_mtx_lock(nfs_buf_mutex);
1194
1195 wakeup_needbuffer = wakeup_buffer = wakeup_nbdwrite = 0;
1196
1197 /* Wake up any processes waiting for any buffer to become free. */
1198 if (nfsneedbuffer) {
1199 nfsneedbuffer = 0;
1200 wakeup_needbuffer = 1;
1201 }
1202 /* Wake up any processes waiting for _this_ buffer to become free. */
1203 if (ISSET(bp->nb_lflags, NBL_WANTED)) {
1204 CLR(bp->nb_lflags, NBL_WANTED);
1205 wakeup_buffer = 1;
1206 }
1207
1208 /* If it's non-needcommit nocache, or an error, mark it invalid. */
1209 if (ISSET(bp->nb_flags, NB_ERROR) ||
1210 (ISSET(bp->nb_flags, NB_NOCACHE) && !ISSET(bp->nb_flags, (NB_NEEDCOMMIT | NB_DELWRI)))) {
1211 SET(bp->nb_flags, NB_INVAL);
1212 }
1213
1214 if ((bp->nb_bufsize <= 0) || ISSET(bp->nb_flags, NB_INVAL)) {
1215 /* If it's invalid or empty, dissociate it from its nfsnode */
1216 if (bp->nb_vnbufs.le_next != NFSNOLIST) {
1217 LIST_REMOVE(bp, nb_vnbufs);
1218 bp->nb_vnbufs.le_next = NFSNOLIST;
1219 }
1220 bp->nb_np = NULL;
1221 /* if this was a delayed write, wakeup anyone */
1222 /* waiting for delayed writes to complete */
1223 if (ISSET(bp->nb_flags, NB_DELWRI)) {
1224 CLR(bp->nb_flags, NB_DELWRI);
1225 nfs_nbdwrite--;
1226 NFSBUFCNTCHK();
1227 wakeup_nbdwrite = 1;
1228 }
1229 /* invalidate usage timestamp to allow immediate freeing */
1230 NBUFSTAMPINVALIDATE(bp);
1231 /* put buffer at head of free list */
1232 if (bp->nb_free.tqe_next != NFSNOLIST) {
1233 panic("nfsbuf on freelist");
1234 }
1235 SET(bp->nb_flags, NB_INVAL);
1236 if (ISSET(bp->nb_flags, NB_META)) {
1237 TAILQ_INSERT_HEAD(&nfsbuffreemeta, bp, nb_free);
1238 nfsbuffreemetacnt++;
1239 } else {
1240 TAILQ_INSERT_HEAD(&nfsbuffree, bp, nb_free);
1241 nfsbuffreecnt++;
1242 }
1243 } else if (ISSET(bp->nb_flags, NB_DELWRI)) {
1244 /* put buffer at end of delwri list */
1245 if (bp->nb_free.tqe_next != NFSNOLIST) {
1246 panic("nfsbuf on freelist");
1247 }
1248 TAILQ_INSERT_TAIL(&nfsbufdelwri, bp, nb_free);
1249 nfsbufdelwricnt++;
1250 freeup = 0;
1251 } else {
1252 /* update usage timestamp */
1253 microuptime(&now);
1254 bp->nb_timestamp = now.tv_sec;
1255 /* put buffer at end of free list */
1256 if (bp->nb_free.tqe_next != NFSNOLIST) {
1257 panic("nfsbuf on freelist");
1258 }
1259 if (ISSET(bp->nb_flags, NB_META)) {
1260 TAILQ_INSERT_TAIL(&nfsbuffreemeta, bp, nb_free);
1261 nfsbuffreemetacnt++;
1262 } else {
1263 TAILQ_INSERT_TAIL(&nfsbuffree, bp, nb_free);
1264 nfsbuffreecnt++;
1265 }
1266 }
1267
1268 NFSBUFCNTCHK();
1269
1270 /* Unlock the buffer. */
1271 CLR(bp->nb_flags, (NB_ASYNC | NB_STABLE));
1272 CLR(bp->nb_lflags, NBL_BUSY);
1273
1274 FSDBG_BOT(548, bp, NBOFF(bp), bp->nb_flags, bp->nb_data);
1275
1276 lck_mtx_unlock(nfs_buf_mutex);
1277
1278 if (wakeup_needbuffer) {
1279 wakeup(&nfsneedbuffer);
1280 }
1281 if (wakeup_buffer) {
1282 wakeup(bp);
1283 }
1284 if (wakeup_nbdwrite) {
1285 wakeup(&nfs_nbdwrite);
1286 }
1287 if (freeup) {
1288 NFS_BUF_FREEUP();
1289 }
1290 }
1291
1292 /*
1293 * Wait for operations on the buffer to complete.
1294 * When they do, extract and return the I/O's error value.
1295 */
1296 int
1297 nfs_buf_iowait(struct nfsbuf *bp)
1298 {
1299 FSDBG_TOP(549, bp, NBOFF(bp), bp->nb_flags, bp->nb_error);
1300
1301 lck_mtx_lock(nfs_buf_mutex);
1302
1303 while (!ISSET(bp->nb_flags, NB_DONE)) {
1304 msleep(bp, nfs_buf_mutex, PRIBIO + 1, "nfs_buf_iowait", NULL);
1305 }
1306
1307 lck_mtx_unlock(nfs_buf_mutex);
1308
1309 FSDBG_BOT(549, bp, NBOFF(bp), bp->nb_flags, bp->nb_error);
1310
1311 /* check for interruption of I/O, then errors. */
1312 if (ISSET(bp->nb_flags, NB_EINTR)) {
1313 CLR(bp->nb_flags, NB_EINTR);
1314 return EINTR;
1315 } else if (ISSET(bp->nb_flags, NB_ERROR)) {
1316 return bp->nb_error ? bp->nb_error : EIO;
1317 }
1318 return 0;
1319 }
1320
1321 /*
1322 * Mark I/O complete on a buffer.
1323 */
1324 void
1325 nfs_buf_iodone(struct nfsbuf *bp)
1326 {
1327 FSDBG_TOP(550, bp, NBOFF(bp), bp->nb_flags, bp->nb_error);
1328
1329 if (ISSET(bp->nb_flags, NB_DONE)) {
1330 panic("nfs_buf_iodone already");
1331 }
1332
1333 if (!ISSET(bp->nb_flags, NB_READ)) {
1334 CLR(bp->nb_flags, NB_WRITEINPROG);
1335 /*
1336 * vnode_writedone() takes care of waking up
1337 * any throttled write operations
1338 */
1339 vnode_writedone(NFSTOV(bp->nb_np));
1340 nfs_node_lock_force(bp->nb_np);
1341 bp->nb_np->n_numoutput--;
1342 nfs_node_unlock(bp->nb_np);
1343 }
1344 if (ISSET(bp->nb_flags, NB_ASYNC)) { /* if async, release it */
1345 SET(bp->nb_flags, NB_DONE); /* note that it's done */
1346 nfs_buf_release(bp, 1);
1347 } else { /* or just wakeup the buffer */
1348 lck_mtx_lock(nfs_buf_mutex);
1349 SET(bp->nb_flags, NB_DONE); /* note that it's done */
1350 CLR(bp->nb_lflags, NBL_WANTED);
1351 lck_mtx_unlock(nfs_buf_mutex);
1352 wakeup(bp);
1353 }
1354
1355 FSDBG_BOT(550, bp, NBOFF(bp), bp->nb_flags, bp->nb_error);
1356 }
1357
1358 void
1359 nfs_buf_write_delayed(struct nfsbuf *bp)
1360 {
1361 nfsnode_t np = bp->nb_np;
1362
1363 FSDBG_TOP(551, bp, NBOFF(bp), bp->nb_flags, 0);
1364 FSDBG(551, bp, bp->nb_dirtyoff, bp->nb_dirtyend, bp->nb_dirty);
1365
1366 /*
1367 * If the block hasn't been seen before:
1368 * (1) Mark it as having been seen,
1369 * (2) Make sure it's on its node's correct block list,
1370 */
1371 if (!ISSET(bp->nb_flags, NB_DELWRI)) {
1372 SET(bp->nb_flags, NB_DELWRI);
1373 /* move to dirty list */
1374 lck_mtx_lock(nfs_buf_mutex);
1375 nfs_nbdwrite++;
1376 NFSBUFCNTCHK();
1377 if (bp->nb_vnbufs.le_next != NFSNOLIST) {
1378 LIST_REMOVE(bp, nb_vnbufs);
1379 }
1380 LIST_INSERT_HEAD(&np->n_dirtyblkhd, bp, nb_vnbufs);
1381 lck_mtx_unlock(nfs_buf_mutex);
1382 }
1383
1384 /*
1385 * If the vnode has "too many" write operations in progress
1386 * wait for them to finish the IO
1387 */
1388 vnode_waitforwrites(NFSTOV(np), VNODE_ASYNC_THROTTLE, 0, 0, "nfs_buf_write_delayed");
1389
1390 /* the file is in a modified state, so make sure the flag's set */
1391 nfs_node_lock_force(np);
1392 np->n_flag |= NMODIFIED;
1393 nfs_node_unlock(np);
1394
1395 /*
1396 * If we have too many delayed write buffers,
1397 * just fall back to doing the async write.
1398 */
1399 if (nfs_nbdwrite < 0) {
1400 panic("nfs_buf_write_delayed: Negative nfs_nbdwrite");
1401 }
1402 if (nfs_nbdwrite > NFS_A_LOT_OF_DELAYED_WRITES) {
1403 /* issue async write */
1404 SET(bp->nb_flags, NB_ASYNC);
1405 nfs_buf_write(bp);
1406 FSDBG_BOT(551, bp, NBOFF(bp), bp->nb_flags, bp->nb_error);
1407 return;
1408 }
1409
1410 /* Otherwise, the "write" is done, so mark and release the buffer. */
1411 SET(bp->nb_flags, NB_DONE);
1412 nfs_buf_release(bp, 1);
1413 FSDBG_BOT(551, bp, NBOFF(bp), bp->nb_flags, 0);
1414 return;
1415 }
1416
1417 /*
1418 * Check that a "needcommit" buffer can still be committed.
1419 * If the write verifier has changed, we need to clear the
1420 * the needcommit flag.
1421 */
1422 void
1423 nfs_buf_check_write_verifier(nfsnode_t np, struct nfsbuf *bp)
1424 {
1425 struct nfsmount *nmp;
1426
1427 if (!ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
1428 return;
1429 }
1430
1431 nmp = NFSTONMP(np);
1432 if (nfs_mount_gone(nmp)) {
1433 return;
1434 }
1435 if (!ISSET(bp->nb_flags, NB_STALEWVERF) && (bp->nb_verf == nmp->nm_verf)) {
1436 return;
1437 }
1438
1439 /* write verifier changed, clear commit/wverf flags */
1440 CLR(bp->nb_flags, (NB_NEEDCOMMIT | NB_STALEWVERF));
1441 bp->nb_verf = 0;
1442 nfs_node_lock_force(np);
1443 np->n_needcommitcnt--;
1444 CHECK_NEEDCOMMITCNT(np);
1445 nfs_node_unlock(np);
1446 }
1447
1448 /*
1449 * add a reference to a buffer so it doesn't disappear while being used
1450 * (must be called with nfs_buf_mutex held)
1451 */
1452 void
1453 nfs_buf_refget(struct nfsbuf *bp)
1454 {
1455 os_ref_retain_locked(&bp->nb_refs);
1456 }
1457 /*
1458 * release a reference on a buffer
1459 * (must be called with nfs_buf_mutex held)
1460 */
1461 void
1462 nfs_buf_refrele(struct nfsbuf *bp)
1463 {
1464 (void) os_ref_release_locked(&bp->nb_refs);
1465 }
1466
1467 /*
1468 * mark a particular buffer as BUSY
1469 * (must be called with nfs_buf_mutex held)
1470 */
1471 errno_t
1472 nfs_buf_acquire(struct nfsbuf *bp, int flags, int slpflag, int slptimeo)
1473 {
1474 errno_t error;
1475 struct timespec ts;
1476
1477 if (ISSET(bp->nb_lflags, NBL_BUSY)) {
1478 /*
1479 * since the lck_mtx_lock may block, the buffer
1480 * may become BUSY, so we need to recheck for
1481 * a NOWAIT request
1482 */
1483 if (flags & NBAC_NOWAIT) {
1484 return EBUSY;
1485 }
1486 SET(bp->nb_lflags, NBL_WANTED);
1487
1488 ts.tv_sec = (slptimeo / 100);
1489 /* the hz value is 100; which leads to 10ms */
1490 ts.tv_nsec = (slptimeo % 100) * 10 * NSEC_PER_USEC * 1000;
1491
1492 error = msleep(bp, nfs_buf_mutex, slpflag | (PRIBIO + 1),
1493 "nfs_buf_acquire", &ts);
1494 if (error) {
1495 return error;
1496 }
1497 return EAGAIN;
1498 }
1499 if (flags & NBAC_REMOVE) {
1500 nfs_buf_remfree(bp);
1501 }
1502 SET(bp->nb_lflags, NBL_BUSY);
1503
1504 return 0;
1505 }
1506
1507 /*
1508 * simply drop the BUSY status of a buffer
1509 * (must be called with nfs_buf_mutex held)
1510 */
1511 void
1512 nfs_buf_drop(struct nfsbuf *bp)
1513 {
1514 int need_wakeup = 0;
1515
1516 if (!ISSET(bp->nb_lflags, NBL_BUSY)) {
1517 panic("nfs_buf_drop: buffer not busy!");
1518 }
1519 if (ISSET(bp->nb_lflags, NBL_WANTED)) {
1520 /* delay the actual wakeup until after we clear NBL_BUSY */
1521 need_wakeup = 1;
1522 }
1523 /* Unlock the buffer. */
1524 CLR(bp->nb_lflags, (NBL_BUSY | NBL_WANTED));
1525
1526 if (need_wakeup) {
1527 wakeup(bp);
1528 }
1529 }
1530
1531 /*
1532 * prepare for iterating over an nfsnode's buffer list
1533 * this lock protects the queue manipulation
1534 * (must be called with nfs_buf_mutex held)
1535 */
1536 int
1537 nfs_buf_iterprepare(nfsnode_t np, struct nfsbuflists *iterheadp, int flags)
1538 {
1539 struct nfsbuflists *listheadp;
1540
1541 if (flags & NBI_DIRTY) {
1542 listheadp = &np->n_dirtyblkhd;
1543 } else {
1544 listheadp = &np->n_cleanblkhd;
1545 }
1546
1547 if ((flags & NBI_NOWAIT) && (np->n_bufiterflags & NBI_ITER)) {
1548 LIST_INIT(iterheadp);
1549 return EWOULDBLOCK;
1550 }
1551
1552 while (np->n_bufiterflags & NBI_ITER) {
1553 np->n_bufiterflags |= NBI_ITERWANT;
1554 msleep(&np->n_bufiterflags, nfs_buf_mutex, 0, "nfs_buf_iterprepare", NULL);
1555 }
1556 if (LIST_EMPTY(listheadp)) {
1557 LIST_INIT(iterheadp);
1558 return EINVAL;
1559 }
1560 np->n_bufiterflags |= NBI_ITER;
1561
1562 iterheadp->lh_first = listheadp->lh_first;
1563 listheadp->lh_first->nb_vnbufs.le_prev = &iterheadp->lh_first;
1564 LIST_INIT(listheadp);
1565
1566 return 0;
1567 }
1568
1569 /*
1570 * clean up after iterating over an nfsnode's buffer list
1571 * this lock protects the queue manipulation
1572 * (must be called with nfs_buf_mutex held)
1573 */
1574 void
1575 nfs_buf_itercomplete(nfsnode_t np, struct nfsbuflists *iterheadp, int flags)
1576 {
1577 struct nfsbuflists * listheadp;
1578 struct nfsbuf *bp;
1579
1580 if (flags & NBI_DIRTY) {
1581 listheadp = &np->n_dirtyblkhd;
1582 } else {
1583 listheadp = &np->n_cleanblkhd;
1584 }
1585
1586 while (!LIST_EMPTY(iterheadp)) {
1587 bp = LIST_FIRST(iterheadp);
1588 LIST_REMOVE(bp, nb_vnbufs);
1589 LIST_INSERT_HEAD(listheadp, bp, nb_vnbufs);
1590 }
1591
1592 np->n_bufiterflags &= ~NBI_ITER;
1593 if (np->n_bufiterflags & NBI_ITERWANT) {
1594 np->n_bufiterflags &= ~NBI_ITERWANT;
1595 wakeup(&np->n_bufiterflags);
1596 }
1597 }
1598
1599
1600 /*
1601 * Read an NFS buffer for a file.
1602 */
1603 int
1604 nfs_buf_read(struct nfsbuf *bp)
1605 {
1606 int error = 0;
1607 nfsnode_t np;
1608 thread_t thd;
1609 kauth_cred_t cred;
1610
1611 np = bp->nb_np;
1612 cred = bp->nb_rcred;
1613 if (IS_VALID_CRED(cred)) {
1614 kauth_cred_ref(cred);
1615 }
1616 thd = ISSET(bp->nb_flags, NB_ASYNC) ? NULL : current_thread();
1617
1618 /* sanity checks */
1619 if (!ISSET(bp->nb_flags, NB_READ)) {
1620 panic("nfs_buf_read: !NB_READ");
1621 }
1622 if (ISSET(bp->nb_flags, NB_DONE)) {
1623 CLR(bp->nb_flags, NB_DONE);
1624 }
1625
1626 NFS_BUF_MAP(bp);
1627
1628 OSAddAtomic64(1, &nfsstats.read_bios);
1629
1630 error = nfs_buf_read_rpc(bp, thd, cred);
1631 /*
1632 * For async I/O, the callbacks will finish up the
1633 * read. Otherwise, the read has already been finished.
1634 */
1635
1636 if (IS_VALID_CRED(cred)) {
1637 kauth_cred_unref(&cred);
1638 }
1639 return error;
1640 }
1641
1642 /*
1643 * finish the reading of a buffer
1644 */
1645 void
1646 nfs_buf_read_finish(struct nfsbuf *bp)
1647 {
1648 nfsnode_t np = bp->nb_np;
1649 struct nfsmount *nmp;
1650
1651 if (!ISSET(bp->nb_flags, NB_ERROR)) {
1652 /* update valid range */
1653 bp->nb_validoff = 0;
1654 bp->nb_validend = bp->nb_endio;
1655 if (bp->nb_endio < bp->nb_bufsize) {
1656 /*
1657 * The read may be short because we have unflushed writes
1658 * that are extending the file size and the reads hit the
1659 * (old) EOF on the server. So, just make sure nb_validend
1660 * correctly tracks EOF.
1661 * Note that the missing data should have already been zeroed
1662 * in nfs_buf_read_rpc_finish().
1663 */
1664 off_t boff = NBOFF(bp);
1665 if ((off_t)np->n_size >= (boff + bp->nb_bufsize)) {
1666 bp->nb_validend = bp->nb_bufsize;
1667 } else if ((off_t)np->n_size >= boff) {
1668 bp->nb_validend = np->n_size - boff;
1669 } else {
1670 bp->nb_validend = 0;
1671 }
1672 }
1673 if ((nmp = NFSTONMP(np)) && (nmp->nm_vers == NFS_VER2) &&
1674 ((NBOFF(bp) + bp->nb_validend) > 0x100000000LL)) {
1675 bp->nb_validend = 0x100000000LL - NBOFF(bp);
1676 }
1677 nfs_buf_pgs_get_page_mask(&bp->nb_valid, round_page_64(bp->nb_validend) / PAGE_SIZE);
1678 if (bp->nb_validend & PAGE_MASK) {
1679 /* zero-fill remainder of last page */
1680 bzero(bp->nb_data + bp->nb_validend, PAGE_SIZE - (bp->nb_validend & PAGE_MASK));
1681 }
1682 }
1683 nfs_buf_iodone(bp);
1684 }
1685
1686 /*
1687 * initiate the NFS READ RPC(s) for a buffer
1688 */
1689 int
1690 nfs_buf_read_rpc(struct nfsbuf *bp, thread_t thd, kauth_cred_t cred)
1691 {
1692 struct nfsmount *nmp;
1693 nfsnode_t np = bp->nb_np;
1694 int error = 0, nfsvers, async;
1695 int offset;
1696 uint64_t length, nrpcs;
1697 uint32_t nmrsize;
1698 size_t len;
1699 off_t boff;
1700 struct nfsreq *req;
1701 struct nfsreq_cbinfo cb;
1702
1703 nmp = NFSTONMP(np);
1704 if (nfs_mount_gone(nmp)) {
1705 bp->nb_error = error = ENXIO;
1706 SET(bp->nb_flags, NB_ERROR);
1707 nfs_buf_iodone(bp);
1708 return error;
1709 }
1710 nfsvers = nmp->nm_vers;
1711 nmrsize = nmp->nm_rsize;
1712
1713 boff = NBOFF(bp);
1714 offset = 0;
1715 length = bp->nb_bufsize;
1716
1717 if (nfsvers == NFS_VER2) {
1718 if (boff > 0xffffffffLL) {
1719 bp->nb_error = error = EFBIG;
1720 SET(bp->nb_flags, NB_ERROR);
1721 nfs_buf_iodone(bp);
1722 return error;
1723 }
1724 if ((boff + length - 1) > 0xffffffffLL) {
1725 length = 0x100000000LL - boff;
1726 }
1727 }
1728
1729 /* Note: Can only do async I/O if nfsiods are configured. */
1730 async = (bp->nb_flags & NB_ASYNC);
1731 cb.rcb_func = async ? nfs_buf_read_rpc_finish : NULL;
1732 cb.rcb_bp = bp;
1733
1734 bp->nb_offio = bp->nb_endio = 0;
1735 bp->nb_rpcs = nrpcs = (length + nmrsize - 1) / nmrsize;
1736 if (async && (nrpcs > 1)) {
1737 SET(bp->nb_flags, NB_MULTASYNCRPC);
1738 } else {
1739 CLR(bp->nb_flags, NB_MULTASYNCRPC);
1740 }
1741
1742 while (length > 0) {
1743 if (ISSET(bp->nb_flags, NB_ERROR)) {
1744 error = bp->nb_error;
1745 break;
1746 }
1747 len = (length > nmrsize) ? nmrsize : (uint32_t)length;
1748 cb.rcb_args.offset = offset;
1749 cb.rcb_args.length = len;
1750 #if CONFIG_NFS4
1751 if (nmp->nm_vers >= NFS_VER4) {
1752 cb.rcb_args.stategenid = nmp->nm_stategenid;
1753 }
1754 #endif
1755 req = NULL;
1756 error = nmp->nm_funcs->nf_read_rpc_async(np, boff + offset, len, thd, cred, &cb, &req);
1757 if (error) {
1758 break;
1759 }
1760 offset += len;
1761 length -= len;
1762 if (async) {
1763 continue;
1764 }
1765 nfs_buf_read_rpc_finish(req);
1766 if (ISSET(bp->nb_flags, NB_ERROR)) {
1767 error = bp->nb_error;
1768 break;
1769 }
1770 }
1771
1772 if (length > 0) {
1773 /*
1774 * Something bad happened while trying to send the RPC(s).
1775 * Wait for any outstanding requests to complete.
1776 */
1777 bp->nb_error = error;
1778 SET(bp->nb_flags, NB_ERROR);
1779 if (ISSET(bp->nb_flags, NB_MULTASYNCRPC)) {
1780 nrpcs = (length + nmrsize - 1) / nmrsize;
1781 lck_mtx_lock(nfs_buf_mutex);
1782 bp->nb_rpcs -= nrpcs;
1783 if (bp->nb_rpcs == 0) {
1784 /* No RPCs left, so the buffer's done */
1785 lck_mtx_unlock(nfs_buf_mutex);
1786 nfs_buf_iodone(bp);
1787 } else {
1788 /* wait for the last RPC to mark it done */
1789 while (bp->nb_rpcs > 0) {
1790 msleep(&bp->nb_rpcs, nfs_buf_mutex, 0,
1791 "nfs_buf_read_rpc_cancel", NULL);
1792 }
1793 lck_mtx_unlock(nfs_buf_mutex);
1794 }
1795 } else {
1796 nfs_buf_iodone(bp);
1797 }
1798 }
1799
1800 return error;
1801 }
1802
1803 /*
1804 * finish up an NFS READ RPC on a buffer
1805 */
1806 void
1807 nfs_buf_read_rpc_finish(struct nfsreq *req)
1808 {
1809 struct nfsmount *nmp;
1810 size_t rlen, length;
1811 struct nfsreq_cbinfo cb;
1812 struct nfsbuf *bp;
1813 int error = 0, nfsvers, eof = 0, multasyncrpc, finished;
1814 off_t offset;
1815 void *wakeme = NULL;
1816 struct nfsreq *rreq = NULL;
1817 nfsnode_t np;
1818 thread_t thd;
1819 kauth_cred_t cred;
1820 uio_t auio;
1821 char uio_buf[UIO_SIZEOF(1)];
1822
1823 finish:
1824 np = req->r_np;
1825 thd = req->r_thread;
1826 cred = req->r_cred;
1827 if (IS_VALID_CRED(cred)) {
1828 kauth_cred_ref(cred);
1829 }
1830 cb = req->r_callback;
1831 bp = cb.rcb_bp;
1832 if (cb.rcb_func) { /* take an extra reference on the nfsreq in case we want to resend it later due to grace error */
1833 nfs_request_ref(req, 0);
1834 }
1835
1836 nmp = NFSTONMP(np);
1837 if (nfs_mount_gone(nmp)) {
1838 SET(bp->nb_flags, NB_ERROR);
1839 bp->nb_error = error = ENXIO;
1840 }
1841 if (error || ISSET(bp->nb_flags, NB_ERROR)) {
1842 /* just drop it */
1843 nfs_request_async_cancel(req);
1844 goto out;
1845 }
1846
1847 nfsvers = nmp->nm_vers;
1848 offset = cb.rcb_args.offset;
1849 rlen = length = cb.rcb_args.length;
1850
1851 auio = uio_createwithbuffer(1, NBOFF(bp) + offset, UIO_SYSSPACE,
1852 UIO_READ, &uio_buf, sizeof(uio_buf));
1853 uio_addiov(auio, CAST_USER_ADDR_T(bp->nb_data + offset), length);
1854
1855 /* finish the RPC */
1856 error = nmp->nm_funcs->nf_read_rpc_async_finish(np, req, auio, &rlen, &eof);
1857 if ((error == EINPROGRESS) && cb.rcb_func) {
1858 /* async request restarted */
1859 if (cb.rcb_func) {
1860 nfs_request_rele(req);
1861 }
1862 if (IS_VALID_CRED(cred)) {
1863 kauth_cred_unref(&cred);
1864 }
1865 return;
1866 }
1867 #if CONFIG_NFS4
1868 if ((nmp->nm_vers >= NFS_VER4) && nfs_mount_state_error_should_restart(error) && !ISSET(bp->nb_flags, NB_ERROR)) {
1869 lck_mtx_lock(&nmp->nm_lock);
1870 if ((error != NFSERR_OLD_STATEID) && (error != NFSERR_GRACE) && (cb.rcb_args.stategenid == nmp->nm_stategenid)) {
1871 NP(np, "nfs_buf_read_rpc_finish: error %d @ 0x%llx, 0x%x 0x%x, initiating recovery",
1872 error, NBOFF(bp) + offset, cb.rcb_args.stategenid, nmp->nm_stategenid);
1873 nfs_need_recover(nmp, error);
1874 }
1875 lck_mtx_unlock(&nmp->nm_lock);
1876 if (np->n_flag & NREVOKE) {
1877 error = EIO;
1878 } else {
1879 if (error == NFSERR_GRACE) {
1880 if (cb.rcb_func) {
1881 /*
1882 * For an async I/O request, handle a grace delay just like
1883 * jukebox errors. Set the resend time and queue it up.
1884 */
1885 struct timeval now;
1886 if (req->r_nmrep.nmc_mhead) {
1887 mbuf_freem(req->r_nmrep.nmc_mhead);
1888 req->r_nmrep.nmc_mhead = NULL;
1889 }
1890 req->r_error = 0;
1891 microuptime(&now);
1892 lck_mtx_lock(&req->r_mtx);
1893 req->r_resendtime = now.tv_sec + 2;
1894 req->r_xid = 0; // get a new XID
1895 req->r_flags |= R_RESTART;
1896 req->r_start = 0;
1897 nfs_asyncio_resend(req);
1898 lck_mtx_unlock(&req->r_mtx);
1899 if (IS_VALID_CRED(cred)) {
1900 kauth_cred_unref(&cred);
1901 }
1902 /* Note: nfsreq reference taken will be dropped later when finished */
1903 return;
1904 }
1905 /* otherwise, just pause a couple seconds and retry */
1906 tsleep(&nmp->nm_state, (PZERO - 1), "nfsgrace", 2 * hz);
1907 }
1908 if (!(error = nfs_mount_state_wait_for_recovery(nmp))) {
1909 rlen = 0;
1910 goto readagain;
1911 }
1912 }
1913 }
1914 #endif
1915 if (error) {
1916 SET(bp->nb_flags, NB_ERROR);
1917 bp->nb_error = error;
1918 goto out;
1919 }
1920
1921 if ((rlen > 0) && (bp->nb_endio < (offset + (int)rlen))) {
1922 bp->nb_endio = offset + rlen;
1923 }
1924
1925 if ((nfsvers == NFS_VER2) || eof || (rlen == 0)) {
1926 /* zero out the remaining data (up to EOF) */
1927 off_t rpcrem, eofrem, rem;
1928 rpcrem = (length - rlen);
1929 eofrem = np->n_size - (NBOFF(bp) + offset + rlen);
1930 rem = (rpcrem < eofrem) ? rpcrem : eofrem;
1931 if (rem > 0) {
1932 NFS_BZERO(bp->nb_data + offset + rlen, rem);
1933 }
1934 } else if ((rlen < length) && !ISSET(bp->nb_flags, NB_ERROR)) {
1935 /*
1936 * short read
1937 *
1938 * We haven't hit EOF and we didn't get all the data
1939 * requested, so we need to issue another read for the rest.
1940 * (Don't bother if the buffer already hit an error.)
1941 */
1942 #if CONFIG_NFS4
1943 readagain:
1944 #endif
1945 offset += rlen;
1946 length -= rlen;
1947 cb.rcb_args.offset = offset;
1948 cb.rcb_args.length = length;
1949 #if CONFIG_NFS4
1950 if (nmp->nm_vers >= NFS_VER4) {
1951 cb.rcb_args.stategenid = nmp->nm_stategenid;
1952 }
1953 #endif
1954 error = nmp->nm_funcs->nf_read_rpc_async(np, NBOFF(bp) + offset, length, thd, cred, &cb, &rreq);
1955 if (!error) {
1956 if (IS_VALID_CRED(cred)) {
1957 kauth_cred_unref(&cred);
1958 }
1959 if (!cb.rcb_func) {
1960 /* if !async we'll need to wait for this RPC to finish */
1961 req = rreq;
1962 rreq = NULL;
1963 goto finish;
1964 }
1965 nfs_request_rele(req);
1966 /*
1967 * We're done here.
1968 * Outstanding RPC count is unchanged.
1969 * Callback will be called when RPC is done.
1970 */
1971 return;
1972 }
1973 SET(bp->nb_flags, NB_ERROR);
1974 bp->nb_error = error;
1975 }
1976
1977 out:
1978 if (cb.rcb_func) {
1979 nfs_request_rele(req);
1980 }
1981 if (IS_VALID_CRED(cred)) {
1982 kauth_cred_unref(&cred);
1983 }
1984
1985 /*
1986 * Decrement outstanding RPC count on buffer
1987 * and call nfs_buf_read_finish on last RPC.
1988 *
1989 * (Note: when there are multiple async RPCs issued for a
1990 * buffer we need nfs_buffer_mutex to avoid problems when
1991 * aborting a partially-initiated set of RPCs)
1992 */
1993
1994 multasyncrpc = ISSET(bp->nb_flags, NB_MULTASYNCRPC);
1995 if (multasyncrpc) {
1996 lck_mtx_lock(nfs_buf_mutex);
1997 }
1998
1999 bp->nb_rpcs--;
2000 finished = (bp->nb_rpcs == 0);
2001
2002 if (multasyncrpc) {
2003 lck_mtx_unlock(nfs_buf_mutex);
2004 }
2005
2006 if (finished) {
2007 if (multasyncrpc) {
2008 wakeme = &bp->nb_rpcs;
2009 }
2010 nfs_buf_read_finish(bp);
2011 if (wakeme) {
2012 wakeup(wakeme);
2013 }
2014 }
2015 }
2016
2017 /*
2018 * Do buffer readahead.
2019 * Initiate async I/O to read buffers not in cache.
2020 */
2021 int
2022 nfs_buf_readahead(nfsnode_t np, int ioflag, daddr64_t *rabnp, daddr64_t lastrabn, thread_t thd, kauth_cred_t cred)
2023 {
2024 struct nfsmount *nmp = NFSTONMP(np);
2025 struct nfsbuf *bp;
2026 int error = 0;
2027 uint32_t nra;
2028
2029 if (nfs_mount_gone(nmp)) {
2030 return ENXIO;
2031 }
2032 if (nmp->nm_readahead <= 0) {
2033 return 0;
2034 }
2035 if (*rabnp > lastrabn) {
2036 return 0;
2037 }
2038
2039 for (nra = 0; (nra < nmp->nm_readahead) && (*rabnp <= lastrabn); nra++, *rabnp = *rabnp + 1) {
2040 /* check if block exists and is valid. */
2041 if ((*rabnp * nmp->nm_biosize) >= (off_t)np->n_size) {
2042 /* stop reading ahead if we're beyond EOF */
2043 *rabnp = lastrabn;
2044 break;
2045 }
2046 error = nfs_buf_get(np, *rabnp, nmp->nm_biosize, thd, NBLK_READ | NBLK_NOWAIT, &bp);
2047 if (error) {
2048 break;
2049 }
2050 nfs_node_lock_force(np);
2051 np->n_lastrahead = *rabnp;
2052 nfs_node_unlock(np);
2053 if (!bp) {
2054 continue;
2055 }
2056 if ((ioflag & IO_NOCACHE) && ISSET(bp->nb_flags, NB_CACHE) &&
2057 !nfs_buf_pgs_is_set(&bp->nb_dirty) && !ISSET(bp->nb_flags, (NB_DELWRI | NB_NCRDAHEAD))) {
2058 CLR(bp->nb_flags, NB_CACHE);
2059 NBPGS_ERASE(&bp->nb_valid);
2060 bp->nb_validoff = bp->nb_validend = -1;
2061 }
2062 if ((bp->nb_dirtyend <= 0) && !nfs_buf_pgs_is_set(&bp->nb_dirty) &&
2063 !ISSET(bp->nb_flags, (NB_CACHE | NB_DELWRI))) {
2064 SET(bp->nb_flags, (NB_READ | NB_ASYNC));
2065 if (ioflag & IO_NOCACHE) {
2066 SET(bp->nb_flags, NB_NCRDAHEAD);
2067 }
2068 if (!IS_VALID_CRED(bp->nb_rcred) && IS_VALID_CRED(cred)) {
2069 kauth_cred_ref(cred);
2070 bp->nb_rcred = cred;
2071 }
2072 if ((error = nfs_buf_read(bp))) {
2073 break;
2074 }
2075 continue;
2076 }
2077 nfs_buf_release(bp, 1);
2078 }
2079 return error;
2080 }
2081
2082 /*
2083 * NFS buffer I/O for reading files.
2084 */
2085 int
2086 nfs_bioread(nfsnode_t np, uio_t uio, int ioflag, vfs_context_t ctx)
2087 {
2088 vnode_t vp = NFSTOV(np);
2089 struct nfsbuf *bp = NULL;
2090 struct nfsmount *nmp = VTONMP(vp);
2091 daddr64_t lbn, rabn = 0, lastrabn, maxrabn = -1;
2092 off_t diff, on = 0, n = 0;
2093 int error = 0, n32;
2094 int nfsvers, biosize, modified, readaheads = 0;
2095 thread_t thd;
2096 kauth_cred_t cred;
2097 int64_t io_resid;
2098
2099 FSDBG_TOP(514, np, uio_offset(uio), uio_resid(uio), ioflag);
2100
2101 nfsvers = nmp->nm_vers;
2102 biosize = nmp->nm_biosize;
2103 thd = vfs_context_thread(ctx);
2104 cred = vfs_context_ucred(ctx);
2105
2106 if (vnode_vtype(vp) != VREG) {
2107 printf("nfs_bioread: type %x unexpected\n", vnode_vtype(vp));
2108 FSDBG_BOT(514, np, 0xd1e0016, 0, EINVAL);
2109 return EINVAL;
2110 }
2111
2112 /*
2113 * For NFS, cache consistency can only be maintained approximately.
2114 * Although RFC1094 does not specify the criteria, the following is
2115 * believed to be compatible with the reference port.
2116 *
2117 * If the file has changed since the last read RPC or you have
2118 * written to the file, you may have lost data cache consistency
2119 * with the server. So, check for a change, and flush all of the
2120 * file's data out of the cache.
2121 * NB: This implies that cache data can be read when up to
2122 * NFS_MAXATTRTIMO seconds out of date. If you find that you
2123 * need current attributes, nfs_getattr() can be forced to fetch
2124 * new attributes (via NATTRINVALIDATE() or NGA_UNCACHED).
2125 */
2126
2127 if (ISSET(np->n_flag, NUPDATESIZE)) {
2128 nfs_data_update_size(np, 0);
2129 }
2130
2131 if ((error = nfs_node_lock(np))) {
2132 FSDBG_BOT(514, np, 0xd1e0222, 0, error);
2133 return error;
2134 }
2135
2136 if (np->n_flag & NNEEDINVALIDATE) {
2137 np->n_flag &= ~NNEEDINVALIDATE;
2138 nfs_node_unlock(np);
2139 error = nfs_vinvalbuf(vp, V_SAVE | V_IGNORE_WRITEERR, ctx, 1);
2140 if (!error) {
2141 error = nfs_node_lock(np);
2142 }
2143 if (error) {
2144 FSDBG_BOT(514, np, 0xd1e0322, 0, error);
2145 return error;
2146 }
2147 }
2148
2149 modified = (np->n_flag & NMODIFIED);
2150 nfs_node_unlock(np);
2151 /* nfs_getattr() will check changed and purge caches */
2152 error = nfs_getattr(np, NULL, ctx, modified ? NGA_UNCACHED : NGA_CACHED);
2153 if (error) {
2154 FSDBG_BOT(514, np, 0xd1e0004, 0, error);
2155 return error;
2156 }
2157
2158 if (uio_resid(uio) == 0) {
2159 FSDBG_BOT(514, np, 0xd1e0001, 0, 0);
2160 return 0;
2161 }
2162 if (uio_offset(uio) < 0) {
2163 FSDBG_BOT(514, np, 0xd1e0002, 0, EINVAL);
2164 return EINVAL;
2165 }
2166
2167 /*
2168 * set up readahead - which may be limited by:
2169 * + current request length (for IO_NOCACHE)
2170 * + readahead setting
2171 * + file size
2172 */
2173 if (nmp->nm_readahead > 0) {
2174 off_t end = uio_offset(uio) + uio_resid(uio);
2175 if (end > (off_t)np->n_size) {
2176 end = np->n_size;
2177 }
2178 rabn = uio_offset(uio) / biosize;
2179 maxrabn = (end - 1) / biosize;
2180 nfs_node_lock_force(np);
2181 if (!(ioflag & IO_NOCACHE) &&
2182 (!rabn || (rabn == np->n_lastread) || (rabn == (np->n_lastread + 1)))) {
2183 maxrabn += nmp->nm_readahead;
2184 if ((maxrabn * biosize) >= (off_t)np->n_size) {
2185 maxrabn = ((off_t)np->n_size - 1) / biosize;
2186 }
2187 }
2188 if (maxrabn < np->n_lastrahead) {
2189 np->n_lastrahead = -1;
2190 }
2191 if (rabn < np->n_lastrahead) {
2192 rabn = np->n_lastrahead + 1;
2193 }
2194 nfs_node_unlock(np);
2195 } else {
2196 rabn = maxrabn = 0;
2197 }
2198
2199 do {
2200 nfs_data_lock(np, NFS_DATA_LOCK_SHARED);
2201 lbn = uio_offset(uio) / biosize;
2202
2203 /*
2204 * Copy directly from any cached pages without grabbing the bufs.
2205 * (If we are NOCACHE and we've issued readahead requests, we need
2206 * to grab the NB_NCRDAHEAD bufs to drop them.)
2207 */
2208 if ((!(ioflag & IO_NOCACHE) || !readaheads) &&
2209 ((uio->uio_segflg == UIO_USERSPACE32 ||
2210 uio->uio_segflg == UIO_USERSPACE64 ||
2211 uio->uio_segflg == UIO_USERSPACE))) {
2212 io_resid = uio_resid(uio);
2213 diff = np->n_size - uio_offset(uio);
2214 if (diff < io_resid) {
2215 io_resid = diff;
2216 }
2217 if (io_resid > 0) {
2218 int count = (io_resid > INT_MAX) ? INT_MAX : (int)io_resid;
2219 error = cluster_copy_ubc_data(vp, uio, &count, 0);
2220 if (error) {
2221 nfs_data_unlock(np);
2222 FSDBG_BOT(514, np, uio_offset(uio), 0xcacefeed, error);
2223 return error;
2224 }
2225 }
2226 /* count any biocache reads that we just copied directly */
2227 if (lbn != (uio_offset(uio) / biosize)) {
2228 OSAddAtomic64(NFS_ROUND_BLOCK(uio_offset(uio), biosize) - lbn, &nfsstats.biocache_reads);
2229 FSDBG(514, np, 0xcacefeed, uio_offset(uio), error);
2230 }
2231 }
2232
2233 lbn = uio_offset(uio) / biosize;
2234 on = uio_offset(uio) % biosize;
2235 nfs_node_lock_force(np);
2236 np->n_lastread = (uio_offset(uio) - 1) / biosize;
2237 nfs_node_unlock(np);
2238
2239 if ((uio_resid(uio) <= 0) || (uio_offset(uio) >= (off_t)np->n_size)) {
2240 nfs_data_unlock(np);
2241 FSDBG_BOT(514, np, uio_offset(uio), uio_resid(uio), 0xaaaaaaaa);
2242 return 0;
2243 }
2244
2245 /* adjust readahead block number, if necessary */
2246 if (rabn < lbn) {
2247 rabn = lbn;
2248 }
2249 lastrabn = MIN(maxrabn, lbn + nmp->nm_readahead);
2250 if (rabn <= lastrabn) { /* start readaheads */
2251 error = nfs_buf_readahead(np, ioflag, &rabn, lastrabn, thd, cred);
2252 if (error) {
2253 nfs_data_unlock(np);
2254 FSDBG_BOT(514, np, 0xd1e000b, 1, error);
2255 return error;
2256 }
2257 readaheads = 1;
2258 OSAddAtomic64(rabn - lbn, &nfsstats.biocache_reads);
2259 } else {
2260 OSAddAtomic64(1, &nfsstats.biocache_reads);
2261 }
2262
2263 /*
2264 * If the block is in the cache and has the required data
2265 * in a valid region, just copy it out.
2266 * Otherwise, get the block and write back/read in,
2267 * as required.
2268 */
2269 again:
2270 io_resid = uio_resid(uio);
2271 n = (io_resid > (biosize - on)) ? (biosize - on) : io_resid;
2272 diff = np->n_size - uio_offset(uio);
2273 if (diff < n) {
2274 n = diff;
2275 }
2276
2277 error = nfs_buf_get(np, lbn, biosize, thd, NBLK_READ, &bp);
2278 if (error) {
2279 nfs_data_unlock(np);
2280 FSDBG_BOT(514, np, 0xd1e000c, 0, error);
2281 return error;
2282 }
2283
2284 if ((ioflag & IO_NOCACHE) && ISSET(bp->nb_flags, NB_CACHE)) {
2285 /*
2286 * IO_NOCACHE found a cached buffer.
2287 * Flush the buffer if it's dirty.
2288 * Invalidate the data if it wasn't just read
2289 * in as part of a "nocache readahead".
2290 */
2291 if (nfs_buf_pgs_is_set(&bp->nb_dirty) || (bp->nb_dirtyend > 0)) {
2292 /* so write the buffer out and try again */
2293 SET(bp->nb_flags, NB_NOCACHE);
2294 goto flushbuffer;
2295 }
2296 if (ISSET(bp->nb_flags, NB_NCRDAHEAD)) {
2297 CLR(bp->nb_flags, NB_NCRDAHEAD);
2298 SET(bp->nb_flags, NB_NOCACHE);
2299 }
2300 }
2301
2302 /* if any pages are valid... */
2303 if (nfs_buf_pgs_is_set(&bp->nb_valid)) {
2304 /* ...check for any invalid pages in the read range */
2305 off_t pg, firstpg, lastpg, dirtypg;
2306 dirtypg = firstpg = lastpg = -1;
2307 pg = on / PAGE_SIZE;
2308 while (pg <= (on + n - 1) / PAGE_SIZE) {
2309 if (!NBPGVALID(bp, pg)) {
2310 if (firstpg < 0) {
2311 firstpg = pg;
2312 }
2313 lastpg = pg;
2314 } else if (firstpg >= 0 && dirtypg < 0 && NBPGDIRTY(bp, pg)) {
2315 dirtypg = pg;
2316 }
2317 pg++;
2318 }
2319
2320 /* if there are no invalid pages, we're all set */
2321 if (firstpg < 0) {
2322 if (bp->nb_validoff < 0) {
2323 /* valid range isn't set up, so */
2324 /* set it to what we know is valid */
2325 bp->nb_validoff = trunc_page_64(on);
2326 bp->nb_validend = round_page_64(on + n);
2327 nfs_buf_normalize_valid_range(np, bp);
2328 }
2329 goto buffer_ready;
2330 }
2331
2332 /* there are invalid pages in the read range */
2333 if (((dirtypg > firstpg) && (dirtypg < lastpg)) ||
2334 (((firstpg * PAGE_SIZE) < bp->nb_dirtyend) && (((lastpg + 1) * PAGE_SIZE) > bp->nb_dirtyoff))) {
2335 /* there are also dirty page(s) (or range) in the read range, */
2336 /* so write the buffer out and try again */
2337 flushbuffer:
2338 CLR(bp->nb_flags, (NB_DONE | NB_ERROR | NB_INVAL));
2339 SET(bp->nb_flags, NB_ASYNC);
2340 if (!IS_VALID_CRED(bp->nb_wcred)) {
2341 kauth_cred_ref(cred);
2342 bp->nb_wcred = cred;
2343 }
2344 error = nfs_buf_write(bp);
2345 if (error) {
2346 nfs_data_unlock(np);
2347 FSDBG_BOT(514, np, 0xd1e000d, 0, error);
2348 return error;
2349 }
2350 goto again;
2351 }
2352 if (!nfs_buf_pgs_is_set(&bp->nb_dirty) && bp->nb_dirtyend <= 0 &&
2353 (lastpg - firstpg + 1) > (biosize / PAGE_SIZE) / 2) {
2354 /* we need to read in more than half the buffer and the */
2355 /* buffer's not dirty, so just fetch the whole buffer */
2356 NBPGS_ERASE(&bp->nb_valid);
2357 } else {
2358 /* read the page range in */
2359 uio_t auio;
2360 char uio_buf[UIO_SIZEOF(1)];
2361
2362 NFS_BUF_MAP(bp);
2363 auio = uio_createwithbuffer(1, (NBOFF(bp) + firstpg * PAGE_SIZE_64),
2364 UIO_SYSSPACE, UIO_READ, &uio_buf[0], sizeof(uio_buf));
2365 if (!auio) {
2366 error = ENOMEM;
2367 } else {
2368 NFS_UIO_ADDIOV(auio, CAST_USER_ADDR_T(bp->nb_data + (firstpg * PAGE_SIZE)),
2369 ((lastpg - firstpg + 1) * PAGE_SIZE));
2370 error = nfs_read_rpc(np, auio, ctx);
2371 }
2372 if (error) {
2373 if (ioflag & IO_NOCACHE) {
2374 SET(bp->nb_flags, NB_NOCACHE);
2375 }
2376 nfs_buf_release(bp, 1);
2377 nfs_data_unlock(np);
2378 FSDBG_BOT(514, np, 0xd1e000e, 0, error);
2379 return error;
2380 }
2381 /* Make sure that the valid range is set to cover this read. */
2382 bp->nb_validoff = trunc_page_64(on);
2383 bp->nb_validend = round_page_64(on + n);
2384 nfs_buf_normalize_valid_range(np, bp);
2385 if (uio_resid(auio) > 0) {
2386 /* if short read, must have hit EOF, */
2387 /* so zero the rest of the range */
2388 bzero(CAST_DOWN(caddr_t, uio_curriovbase(auio)), uio_resid(auio));
2389 }
2390 /* mark the pages (successfully read) as valid */
2391 for (pg = firstpg; pg <= lastpg; pg++) {
2392 NBPGVALID_SET(bp, pg);
2393 }
2394 }
2395 }
2396 /* if no pages are valid, read the whole block */
2397 if (!nfs_buf_pgs_is_set(&bp->nb_valid)) {
2398 if (!IS_VALID_CRED(bp->nb_rcred) && IS_VALID_CRED(cred)) {
2399 kauth_cred_ref(cred);
2400 bp->nb_rcred = cred;
2401 }
2402 SET(bp->nb_flags, NB_READ);
2403 CLR(bp->nb_flags, (NB_DONE | NB_ERROR | NB_INVAL));
2404 error = nfs_buf_read(bp);
2405 if (ioflag & IO_NOCACHE) {
2406 SET(bp->nb_flags, NB_NOCACHE);
2407 }
2408 if (error) {
2409 nfs_data_unlock(np);
2410 nfs_buf_release(bp, 1);
2411 FSDBG_BOT(514, np, 0xd1e000f, 0, error);
2412 return error;
2413 }
2414 }
2415 buffer_ready:
2416 /* validate read range against valid range and clip */
2417 if (bp->nb_validend > 0) {
2418 diff = (on >= bp->nb_validend) ? 0 : (bp->nb_validend - on);
2419 if (diff < n) {
2420 n = diff;
2421 }
2422 }
2423 if (n > 0) {
2424 NFS_BUF_MAP(bp);
2425 n32 = n > INT_MAX ? INT_MAX : (int)n;
2426 error = uiomove(bp->nb_data + on, n32, uio);
2427 if (!error && n > n32) {
2428 error = uiomove(bp->nb_data + on + n32, (int)(n - n32), uio);
2429 }
2430 }
2431
2432
2433 nfs_buf_release(bp, 1);
2434 nfs_data_unlock(np);
2435 nfs_node_lock_force(np);
2436 np->n_lastread = (uio_offset(uio) - 1) / biosize;
2437 nfs_node_unlock(np);
2438 } while (error == 0 && uio_resid(uio) > 0 && n > 0);
2439 FSDBG_BOT(514, np, uio_offset(uio), uio_resid(uio), error);
2440 return error;
2441 }
2442
2443 /*
2444 * limit the number of outstanding async I/O writes
2445 */
2446 int
2447 nfs_async_write_start(struct nfsmount *nmp)
2448 {
2449 int error = 0, slpflag = NMFLAG(nmp, INTR) ? PCATCH : 0;
2450 struct timespec ts = { .tv_sec = 1, .tv_nsec = 0 };
2451
2452 if (nfs_max_async_writes <= 0) {
2453 return 0;
2454 }
2455 lck_mtx_lock(&nmp->nm_lock);
2456 while ((nfs_max_async_writes > 0) && (nmp->nm_asyncwrites >= nfs_max_async_writes)) {
2457 if ((error = nfs_sigintr(nmp, NULL, current_thread(), 1))) {
2458 break;
2459 }
2460 msleep(&nmp->nm_asyncwrites, &nmp->nm_lock, slpflag | (PZERO - 1), "nfsasyncwrites", &ts);
2461 slpflag = 0;
2462 }
2463 if (!error) {
2464 nmp->nm_asyncwrites++;
2465 }
2466 lck_mtx_unlock(&nmp->nm_lock);
2467 return error;
2468 }
2469 void
2470 nfs_async_write_done(struct nfsmount *nmp)
2471 {
2472 if (nmp->nm_asyncwrites <= 0) {
2473 return;
2474 }
2475 lck_mtx_lock(&nmp->nm_lock);
2476 if (nmp->nm_asyncwrites-- >= nfs_max_async_writes) {
2477 wakeup(&nmp->nm_asyncwrites);
2478 }
2479 lck_mtx_unlock(&nmp->nm_lock);
2480 }
2481
2482 /*
2483 * write (or commit) the given NFS buffer
2484 *
2485 * Commit the buffer if we can.
2486 * Write out any dirty range.
2487 * If any dirty pages remain, write them out.
2488 * Mark buffer done.
2489 *
2490 * For async requests, all the work beyond sending the initial
2491 * write RPC is handled in the RPC callback(s).
2492 */
2493 int
2494 nfs_buf_write(struct nfsbuf *bp)
2495 {
2496 int error = 0, oldflags, async;
2497 nfsnode_t np;
2498 thread_t thd;
2499 kauth_cred_t cred;
2500 proc_t p = current_proc();
2501 int iomode;
2502 off_t doff, dend, firstpg, lastpg;
2503
2504 FSDBG_TOP(553, bp, NBOFF(bp), bp->nb_flags, 0);
2505
2506 if (!ISSET(bp->nb_lflags, NBL_BUSY)) {
2507 panic("nfs_buf_write: buffer is not busy???");
2508 }
2509
2510 np = bp->nb_np;
2511 async = ISSET(bp->nb_flags, NB_ASYNC);
2512 oldflags = bp->nb_flags;
2513
2514 CLR(bp->nb_flags, (NB_READ | NB_DONE | NB_ERROR | NB_DELWRI));
2515 if (ISSET(oldflags, NB_DELWRI)) {
2516 lck_mtx_lock(nfs_buf_mutex);
2517 nfs_nbdwrite--;
2518 NFSBUFCNTCHK();
2519 lck_mtx_unlock(nfs_buf_mutex);
2520 wakeup(&nfs_nbdwrite);
2521 }
2522
2523 /* move to clean list */
2524 if (ISSET(oldflags, (NB_ASYNC | NB_DELWRI))) {
2525 lck_mtx_lock(nfs_buf_mutex);
2526 if (bp->nb_vnbufs.le_next != NFSNOLIST) {
2527 LIST_REMOVE(bp, nb_vnbufs);
2528 }
2529 LIST_INSERT_HEAD(&np->n_cleanblkhd, bp, nb_vnbufs);
2530 lck_mtx_unlock(nfs_buf_mutex);
2531 }
2532 nfs_node_lock_force(np);
2533 np->n_numoutput++;
2534 nfs_node_unlock(np);
2535 vnode_startwrite(NFSTOV(np));
2536
2537 if (p && p->p_stats) {
2538 OSIncrementAtomicLong(&p->p_stats->p_ru.ru_oublock);
2539 }
2540
2541 cred = bp->nb_wcred;
2542 if (!IS_VALID_CRED(cred) && ISSET(bp->nb_flags, NB_READ)) {
2543 cred = bp->nb_rcred; /* shouldn't really happen, but... */
2544 }
2545 if (IS_VALID_CRED(cred)) {
2546 kauth_cred_ref(cred);
2547 }
2548 thd = async ? NULL : current_thread();
2549
2550 /* We need to make sure the pages are locked before doing I/O. */
2551 if (!ISSET(bp->nb_flags, NB_META)) {
2552 if (UBCINFOEXISTS(NFSTOV(np))) {
2553 if (!ISSET(bp->nb_flags, NB_PAGELIST)) {
2554 error = nfs_buf_upl_setup(bp);
2555 if (error) {
2556 printf("nfs_buf_write: upl create failed %d\n", error);
2557 SET(bp->nb_flags, NB_ERROR);
2558 bp->nb_error = error = EIO;
2559 nfs_buf_iodone(bp);
2560 goto out;
2561 }
2562 nfs_buf_upl_check(bp);
2563 }
2564 } else {
2565 /* We should never be in nfs_buf_write() with no UBCINFO. */
2566 printf("nfs_buf_write: ubcinfo already gone\n");
2567 SET(bp->nb_flags, NB_ERROR);
2568 bp->nb_error = error = EIO;
2569 nfs_buf_iodone(bp);
2570 goto out;
2571 }
2572 }
2573
2574 /* If NB_NEEDCOMMIT is set, a commit RPC may do the trick. */
2575 if (ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
2576 nfs_buf_check_write_verifier(np, bp);
2577 }
2578 if (ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
2579 struct nfsmount *nmp = NFSTONMP(np);
2580 if (nfs_mount_gone(nmp)) {
2581 SET(bp->nb_flags, NB_ERROR);
2582 bp->nb_error = error = EIO;
2583 nfs_buf_iodone(bp);
2584 goto out;
2585 }
2586 SET(bp->nb_flags, NB_WRITEINPROG);
2587 error = nmp->nm_funcs->nf_commit_rpc(np, NBOFF(bp) + bp->nb_dirtyoff,
2588 bp->nb_dirtyend - bp->nb_dirtyoff, bp->nb_wcred, bp->nb_verf);
2589 CLR(bp->nb_flags, NB_WRITEINPROG);
2590 if (error) {
2591 if (error != NFSERR_STALEWRITEVERF) {
2592 SET(bp->nb_flags, NB_ERROR);
2593 bp->nb_error = error;
2594 }
2595 nfs_buf_iodone(bp);
2596 goto out;
2597 }
2598 bp->nb_dirtyoff = bp->nb_dirtyend = 0;
2599 CLR(bp->nb_flags, NB_NEEDCOMMIT);
2600 nfs_node_lock_force(np);
2601 np->n_needcommitcnt--;
2602 CHECK_NEEDCOMMITCNT(np);
2603 nfs_node_unlock(np);
2604 }
2605 if (!error && (bp->nb_dirtyend > 0)) {
2606 /* sanity check the dirty range */
2607 if (NBOFF(bp) + bp->nb_dirtyend > (off_t) np->n_size) {
2608 bp->nb_dirtyend = np->n_size - NBOFF(bp);
2609 if (bp->nb_dirtyoff >= bp->nb_dirtyend) {
2610 bp->nb_dirtyoff = bp->nb_dirtyend = 0;
2611 }
2612 }
2613 }
2614 if (!error && (bp->nb_dirtyend > 0)) {
2615 /* there's a dirty range that needs to be written out */
2616 nfsbufpgs pagemask, pagemaskand;
2617 NFS_BUF_MAP(bp);
2618
2619 doff = bp->nb_dirtyoff;
2620 dend = bp->nb_dirtyend;
2621
2622 /* if doff page is dirty, move doff to start of page */
2623 if (NBPGDIRTY(bp, doff / PAGE_SIZE)) {
2624 doff -= doff & PAGE_MASK;
2625 }
2626 /* try to expand write range to include preceding dirty pages */
2627 if (!(doff & PAGE_MASK)) {
2628 while ((doff > 0) && NBPGDIRTY(bp, (doff - 1) / PAGE_SIZE)) {
2629 doff -= PAGE_SIZE;
2630 }
2631 }
2632 /* if dend page is dirty, move dend to start of next page */
2633 if ((dend & PAGE_MASK) && NBPGDIRTY(bp, dend / PAGE_SIZE)) {
2634 dend = round_page_64(dend);
2635 }
2636 /* try to expand write range to include trailing dirty pages */
2637 if (!(dend & PAGE_MASK)) {
2638 while ((dend < (int)bp->nb_bufsize) && NBPGDIRTY(bp, dend / PAGE_SIZE)) {
2639 dend += PAGE_SIZE;
2640 }
2641 }
2642 /* make sure to keep dend clipped to EOF */
2643 if ((NBOFF(bp) + dend) > (off_t) np->n_size) {
2644 dend = np->n_size - NBOFF(bp);
2645 }
2646 /* calculate range of complete pages being written */
2647 if (dend > doff) {
2648 firstpg = doff / PAGE_SIZE;
2649 lastpg = (dend - 1) / PAGE_SIZE;
2650 /* calculate mask for that page range */
2651 nfs_buf_pgs_set_pages_between(&pagemask, firstpg, lastpg + 1);
2652 } else {
2653 NBPGS_ERASE(&pagemask);
2654 }
2655
2656 /*
2657 * compare page mask to nb_dirty; if there are other dirty pages
2658 * then write FILESYNC; otherwise, write UNSTABLE if async and
2659 * not needcommit/stable; otherwise write FILESYNC
2660 */
2661 nfs_buf_pgs_bit_not(&pagemask);
2662 nfs_buf_pgs_bit_and(&bp->nb_dirty, &pagemask, &pagemaskand);
2663 if (nfs_buf_pgs_is_set(&pagemaskand)) {
2664 iomode = NFS_WRITE_FILESYNC;
2665 } else if ((bp->nb_flags & (NB_ASYNC | NB_NEEDCOMMIT | NB_STABLE)) == NB_ASYNC) {
2666 iomode = NFS_WRITE_UNSTABLE;
2667 } else {
2668 iomode = NFS_WRITE_FILESYNC;
2669 }
2670
2671 /* write the whole contiguous dirty range */
2672 bp->nb_offio = doff;
2673 bp->nb_endio = dend;
2674
2675 OSAddAtomic64(1, &nfsstats.write_bios);
2676
2677 SET(bp->nb_flags, NB_WRITEINPROG);
2678 error = nfs_buf_write_rpc(bp, iomode, thd, cred);
2679 /*
2680 * For async I/O, the callbacks will finish up the
2681 * write and push out any dirty pages. Otherwise,
2682 * the write has already been finished and any dirty
2683 * pages pushed out.
2684 */
2685 } else {
2686 if (!error && nfs_buf_pgs_is_set(&bp->nb_dirty)) { /* write out any dirty pages */
2687 error = nfs_buf_write_dirty_pages(bp, thd, cred);
2688 }
2689 nfs_buf_iodone(bp);
2690 }
2691 /* note: bp is still valid only for !async case */
2692 out:
2693 if (!async) {
2694 error = nfs_buf_iowait(bp);
2695 /* move to clean list */
2696 if (oldflags & NB_DELWRI) {
2697 lck_mtx_lock(nfs_buf_mutex);
2698 if (bp->nb_vnbufs.le_next != NFSNOLIST) {
2699 LIST_REMOVE(bp, nb_vnbufs);
2700 }
2701 LIST_INSERT_HEAD(&np->n_cleanblkhd, bp, nb_vnbufs);
2702 lck_mtx_unlock(nfs_buf_mutex);
2703 }
2704 FSDBG_BOT(553, bp, NBOFF(bp), bp->nb_flags, error);
2705 nfs_buf_release(bp, 1);
2706 /* check if we need to invalidate (and we can) */
2707 if ((np->n_flag & NNEEDINVALIDATE) &&
2708 !(np->n_bflag & (NBINVALINPROG | NBFLUSHINPROG))) {
2709 int invalidate = 0;
2710 nfs_node_lock_force(np);
2711 if (np->n_flag & NNEEDINVALIDATE) {
2712 invalidate = 1;
2713 np->n_flag &= ~NNEEDINVALIDATE;
2714 }
2715 nfs_node_unlock(np);
2716 if (invalidate) {
2717 /*
2718 * There was a write error and we need to
2719 * invalidate attrs and flush buffers in
2720 * order to sync up with the server.
2721 * (if this write was extending the file,
2722 * we may no longer know the correct size)
2723 *
2724 * But we couldn't call vinvalbuf while holding
2725 * the buffer busy. So we call vinvalbuf() after
2726 * releasing the buffer.
2727 */
2728 nfs_vinvalbuf2(NFSTOV(np), V_SAVE | V_IGNORE_WRITEERR, thd, cred, 1);
2729 }
2730 }
2731 }
2732
2733 if (IS_VALID_CRED(cred)) {
2734 kauth_cred_unref(&cred);
2735 }
2736 return error;
2737 }
2738
2739 /*
2740 * finish the writing of a buffer
2741 */
2742 void
2743 nfs_buf_write_finish(struct nfsbuf *bp, thread_t thd, kauth_cred_t cred)
2744 {
2745 nfsnode_t np = bp->nb_np;
2746 int error = (bp->nb_flags & NB_ERROR) ? bp->nb_error : 0;
2747 off_t firstpg, lastpg;
2748
2749 if ((error == EINTR) || (error == ERESTART)) {
2750 CLR(bp->nb_flags, NB_ERROR);
2751 SET(bp->nb_flags, NB_EINTR);
2752 }
2753
2754 if (!error) {
2755 nfsbufpgs pagemask;
2756 /* calculate range of complete pages being written */
2757 if (bp->nb_endio > bp->nb_offio) {
2758 firstpg = bp->nb_offio / PAGE_SIZE;
2759 lastpg = (bp->nb_endio - 1) / PAGE_SIZE;
2760 /* calculate mask for that page range written */
2761 nfs_buf_pgs_set_pages_between(&pagemask, firstpg, lastpg + 1);
2762 } else {
2763 NBPGS_ERASE(&pagemask);
2764 }
2765 /* clear dirty bits for pages we've written */
2766 nfs_buf_pgs_bit_not(&pagemask);
2767 nfs_buf_pgs_bit_and(&bp->nb_dirty, &pagemask, &bp->nb_dirty);
2768 }
2769
2770 /* manage needcommit state */
2771 if (!error && (bp->nb_commitlevel == NFS_WRITE_UNSTABLE)) {
2772 if (!ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
2773 nfs_node_lock_force(np);
2774 np->n_needcommitcnt++;
2775 nfs_node_unlock(np);
2776 SET(bp->nb_flags, NB_NEEDCOMMIT);
2777 }
2778 /* make sure nb_dirtyoff/nb_dirtyend reflect actual range written */
2779 bp->nb_dirtyoff = bp->nb_offio;
2780 bp->nb_dirtyend = bp->nb_endio;
2781 } else if (ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
2782 nfs_node_lock_force(np);
2783 np->n_needcommitcnt--;
2784 CHECK_NEEDCOMMITCNT(np);
2785 nfs_node_unlock(np);
2786 CLR(bp->nb_flags, NB_NEEDCOMMIT);
2787 }
2788
2789 CLR(bp->nb_flags, NB_WRITEINPROG);
2790
2791 /*
2792 * For an unstable write, the buffer is still treated as dirty until
2793 * a commit (or stable (re)write) is performed. Buffers needing only
2794 * a commit are marked with the NB_DELWRI and NB_NEEDCOMMIT flags.
2795 *
2796 * If the write was interrupted we set NB_EINTR. Don't set NB_ERROR
2797 * because that would cause the buffer to be dropped. The buffer is
2798 * still valid and simply needs to be written again.
2799 */
2800 if ((error == EINTR) || (error == ERESTART) || (!error && (bp->nb_flags & NB_NEEDCOMMIT))) {
2801 CLR(bp->nb_flags, NB_INVAL);
2802 if (!ISSET(bp->nb_flags, NB_DELWRI)) {
2803 SET(bp->nb_flags, NB_DELWRI);
2804 lck_mtx_lock(nfs_buf_mutex);
2805 nfs_nbdwrite++;
2806 NFSBUFCNTCHK();
2807 lck_mtx_unlock(nfs_buf_mutex);
2808 }
2809 /*
2810 * Since for the NB_ASYNC case, we've reassigned the buffer to the
2811 * clean list, we have to reassign it back to the dirty one. Ugh.
2812 */
2813 if (ISSET(bp->nb_flags, NB_ASYNC)) {
2814 /* move to dirty list */
2815 lck_mtx_lock(nfs_buf_mutex);
2816 if (bp->nb_vnbufs.le_next != NFSNOLIST) {
2817 LIST_REMOVE(bp, nb_vnbufs);
2818 }
2819 LIST_INSERT_HEAD(&np->n_dirtyblkhd, bp, nb_vnbufs);
2820 lck_mtx_unlock(nfs_buf_mutex);
2821 }
2822 } else {
2823 /* either there's an error or we don't need to commit */
2824 if (error) {
2825 /*
2826 * There was a write error and we need to invalidate
2827 * attrs and flush buffers in order to sync up with the
2828 * server. (if this write was extending the file, we
2829 * may no longer know the correct size)
2830 *
2831 * But we can't call vinvalbuf while holding this
2832 * buffer busy. Set a flag to do it after releasing
2833 * the buffer.
2834 */
2835 nfs_node_lock_force(np);
2836 np->n_error = error;
2837 np->n_flag |= (NWRITEERR | NNEEDINVALIDATE);
2838 NATTRINVALIDATE(np);
2839 nfs_node_unlock(np);
2840 }
2841 /* clear the dirty range */
2842 bp->nb_dirtyoff = bp->nb_dirtyend = 0;
2843 }
2844
2845 if (!error && nfs_buf_pgs_is_set(&bp->nb_dirty)) {
2846 nfs_buf_write_dirty_pages(bp, thd, cred);
2847 }
2848 nfs_buf_iodone(bp);
2849 }
2850
2851 /*
2852 * write out any pages marked dirty in a buffer
2853 *
2854 * We do use unstable writes and follow up with a commit.
2855 * If we catch the write verifier changing we'll restart
2856 * do the writes filesync.
2857 */
2858 int
2859 nfs_buf_write_dirty_pages(struct nfsbuf *bp, thread_t thd, kauth_cred_t cred)
2860 {
2861 nfsnode_t np = bp->nb_np;
2862 struct nfsmount *nmp = NFSTONMP(np);
2863 int error = 0, commit, iomode, iomode2, len, pg, count, npages, off;
2864 nfsbufpgs dirty;
2865 uint64_t wverf;
2866 uio_t auio;
2867 char uio_buf[UIO_SIZEOF(1)];
2868
2869 if (!nfs_buf_pgs_is_set(&bp->nb_dirty)) {
2870 return 0;
2871 }
2872
2873 /* there are pages marked dirty that need to be written out */
2874 OSAddAtomic64(1, &nfsstats.write_bios);
2875 NFS_BUF_MAP(bp);
2876 SET(bp->nb_flags, NB_WRITEINPROG);
2877 npages = bp->nb_bufsize / PAGE_SIZE;
2878 iomode = NFS_WRITE_UNSTABLE;
2879
2880 auio = uio_createwithbuffer(1, 0, UIO_SYSSPACE, UIO_WRITE,
2881 &uio_buf, sizeof(uio_buf));
2882
2883 again:
2884 NBPGS_COPY(&dirty, &bp->nb_dirty);
2885 wverf = bp->nb_verf;
2886 commit = NFS_WRITE_FILESYNC;
2887 for (pg = 0; pg < npages; pg++) {
2888 if (!NBPGDIRTY(bp, pg)) {
2889 continue;
2890 }
2891 count = 1;
2892 while (((pg + count) < npages) && NBPGDIRTY(bp, pg + count)) {
2893 count++;
2894 }
2895 /* write count pages starting with page pg */
2896 off = pg * PAGE_SIZE;
2897 len = count * PAGE_SIZE;
2898 /* clip writes to EOF */
2899 if (NBOFF(bp) + off + len > (off_t) np->n_size) {
2900 len -= (NBOFF(bp) + off + len) - np->n_size;
2901 }
2902 if (len > 0) {
2903 iomode2 = iomode;
2904 uio_reset(auio, NBOFF(bp) + off, UIO_SYSSPACE, UIO_WRITE);
2905 uio_addiov(auio, CAST_USER_ADDR_T(bp->nb_data + off), len);
2906 error = nfs_write_rpc2(np, auio, thd, cred, &iomode2, &bp->nb_verf);
2907 if (error) {
2908 break;
2909 }
2910 if (iomode2 < commit) { /* Retain the lowest commitment level returned. */
2911 commit = iomode2;
2912 }
2913 if ((commit != NFS_WRITE_FILESYNC) && (wverf != bp->nb_verf)) {
2914 /* verifier changed, redo all the writes filesync */
2915 iomode = NFS_WRITE_FILESYNC;
2916 goto again;
2917 }
2918 }
2919 /* clear dirty bits */
2920 while (count--) {
2921 NBPGS_UNSET(&dirty, pg);
2922 if (count) { /* leave pg on last page */
2923 pg++;
2924 }
2925 }
2926 }
2927 CLR(bp->nb_flags, NB_WRITEINPROG);
2928
2929 if (!error && (commit != NFS_WRITE_FILESYNC)) {
2930 error = nmp->nm_funcs->nf_commit_rpc(np, NBOFF(bp), bp->nb_bufsize, cred, wverf);
2931 if (error == NFSERR_STALEWRITEVERF) {
2932 /* verifier changed, so we need to restart all the writes */
2933 iomode = NFS_WRITE_FILESYNC;
2934 goto again;
2935 }
2936 }
2937 if (!error) {
2938 NBPGS_COPY(&bp->nb_dirty, &dirty);
2939 } else {
2940 SET(bp->nb_flags, NB_ERROR);
2941 bp->nb_error = error;
2942 }
2943 return error;
2944 }
2945
2946 /*
2947 * initiate the NFS WRITE RPC(s) for a buffer
2948 */
2949 int
2950 nfs_buf_write_rpc(struct nfsbuf *bp, int iomode, thread_t thd, kauth_cred_t cred)
2951 {
2952 struct nfsmount *nmp;
2953 nfsnode_t np = bp->nb_np;
2954 int error = 0, nfsvers, async;
2955 int64_t nrpcs;
2956 size_t len;
2957 uint32_t nmwsize;
2958 struct nfsreq *req;
2959 struct nfsreq_cbinfo cb;
2960 uio_t auio;
2961 char uio_buf[UIO_SIZEOF(1)];
2962 off_t offset, length;
2963
2964 nmp = NFSTONMP(np);
2965 if (nfs_mount_gone(nmp)) {
2966 bp->nb_error = error = ENXIO;
2967 SET(bp->nb_flags, NB_ERROR);
2968 nfs_buf_iodone(bp);
2969 return error;
2970 }
2971 nfsvers = nmp->nm_vers;
2972 nmwsize = nmp->nm_wsize;
2973
2974 offset = bp->nb_offio;
2975 length = bp->nb_endio - bp->nb_offio;
2976
2977 /* Note: Can only do async I/O if nfsiods are configured. */
2978 async = (bp->nb_flags & NB_ASYNC) && (NFSIOD_MAX > 0);
2979 bp->nb_commitlevel = NFS_WRITE_FILESYNC;
2980 cb.rcb_func = async ? nfs_buf_write_rpc_finish : NULL;
2981 cb.rcb_bp = bp;
2982
2983 if ((nfsvers == NFS_VER2) && ((NBOFF(bp) + bp->nb_endio) > 0xffffffffLL)) {
2984 bp->nb_error = error = EFBIG;
2985 SET(bp->nb_flags, NB_ERROR);
2986 nfs_buf_iodone(bp);
2987 return error;
2988 }
2989
2990 auio = uio_createwithbuffer(1, NBOFF(bp) + offset, UIO_SYSSPACE,
2991 UIO_WRITE, &uio_buf, sizeof(uio_buf));
2992 NFS_UIO_ADDIOV(auio, CAST_USER_ADDR_T(bp->nb_data + offset), length);
2993
2994 bp->nb_rpcs = nrpcs = (length + nmwsize - 1) / nmwsize;
2995 if (async && (nrpcs > 1)) {
2996 SET(bp->nb_flags, NB_MULTASYNCRPC);
2997 } else {
2998 CLR(bp->nb_flags, NB_MULTASYNCRPC);
2999 }
3000
3001 while (length > 0) {
3002 if (ISSET(bp->nb_flags, NB_ERROR)) {
3003 error = bp->nb_error;
3004 break;
3005 }
3006 len = (length > nmwsize) ? nmwsize : (uint32_t)length;
3007 cb.rcb_args.offset = offset;
3008 cb.rcb_args.length = len;
3009 #if CONFIG_NFS4
3010 if (nmp->nm_vers >= NFS_VER4) {
3011 cb.rcb_args.stategenid = nmp->nm_stategenid;
3012 }
3013 #endif
3014 if (async && ((error = nfs_async_write_start(nmp)))) {
3015 break;
3016 }
3017 req = NULL;
3018 error = nmp->nm_funcs->nf_write_rpc_async(np, auio, len, thd, cred,
3019 iomode, &cb, &req);
3020 if (error) {
3021 if (async) {
3022 nfs_async_write_done(nmp);
3023 }
3024 break;
3025 }
3026 offset += len;
3027 length -= len;
3028 if (async) {
3029 continue;
3030 }
3031 nfs_buf_write_rpc_finish(req);
3032 }
3033
3034 if (length > 0) {
3035 /*
3036 * Something bad happened while trying to send the RPCs.
3037 * Wait for any outstanding requests to complete.
3038 */
3039 bp->nb_error = error;
3040 SET(bp->nb_flags, NB_ERROR);
3041 if (ISSET(bp->nb_flags, NB_MULTASYNCRPC)) {
3042 nrpcs = (length + nmwsize - 1) / nmwsize;
3043 lck_mtx_lock(nfs_buf_mutex);
3044 bp->nb_rpcs -= nrpcs;
3045 if (bp->nb_rpcs == 0) {
3046 /* No RPCs left, so the buffer's done */
3047 lck_mtx_unlock(nfs_buf_mutex);
3048 nfs_buf_write_finish(bp, thd, cred);
3049 } else {
3050 /* wait for the last RPC to mark it done */
3051 while (bp->nb_rpcs > 0) {
3052 msleep(&bp->nb_rpcs, nfs_buf_mutex, 0,
3053 "nfs_buf_write_rpc_cancel", NULL);
3054 }
3055 lck_mtx_unlock(nfs_buf_mutex);
3056 }
3057 } else {
3058 nfs_buf_write_finish(bp, thd, cred);
3059 }
3060 /* It may have just been an interrupt... that's OK */
3061 if (!ISSET(bp->nb_flags, NB_ERROR)) {
3062 error = 0;
3063 }
3064 }
3065
3066 return error;
3067 }
3068
3069 /*
3070 * finish up an NFS WRITE RPC on a buffer
3071 */
3072 void
3073 nfs_buf_write_rpc_finish(struct nfsreq *req)
3074 {
3075 int error = 0, nfsvers, multasyncrpc, finished;
3076 int committed = NFS_WRITE_FILESYNC;
3077 uint64_t wverf = 0;
3078 off_t offset;
3079 size_t rlen, length;
3080 void *wakeme = NULL;
3081 struct nfsreq_cbinfo cb;
3082 struct nfsreq *wreq = NULL;
3083 struct nfsbuf *bp;
3084 struct nfsmount *nmp;
3085 nfsnode_t np;
3086 thread_t thd;
3087 kauth_cred_t cred;
3088 uio_t auio;
3089 char uio_buf[UIO_SIZEOF(1)];
3090
3091 finish:
3092 np = req->r_np;
3093 thd = req->r_thread;
3094 cred = req->r_cred;
3095 if (IS_VALID_CRED(cred)) {
3096 kauth_cred_ref(cred);
3097 }
3098 cb = req->r_callback;
3099 bp = cb.rcb_bp;
3100 if (cb.rcb_func) { /* take an extra reference on the nfsreq in case we want to resend it later due to grace error */
3101 nfs_request_ref(req, 0);
3102 }
3103
3104 nmp = NFSTONMP(np);
3105 if (nfs_mount_gone(nmp)) {
3106 SET(bp->nb_flags, NB_ERROR);
3107 bp->nb_error = error = ENXIO;
3108 }
3109 if (error || ISSET(bp->nb_flags, NB_ERROR)) {
3110 /* just drop it */
3111 nfs_request_async_cancel(req);
3112 goto out;
3113 }
3114 nfsvers = nmp->nm_vers;
3115
3116 offset = cb.rcb_args.offset;
3117 rlen = length = cb.rcb_args.length;
3118
3119 /* finish the RPC */
3120 error = nmp->nm_funcs->nf_write_rpc_async_finish(np, req, &committed, &rlen, &wverf);
3121 if ((error == EINPROGRESS) && cb.rcb_func) {
3122 /* async request restarted */
3123 if (cb.rcb_func) {
3124 nfs_request_rele(req);
3125 }
3126 if (IS_VALID_CRED(cred)) {
3127 kauth_cred_unref(&cred);
3128 }
3129 return;
3130 }
3131 #if CONFIG_NFS4
3132 if ((nmp->nm_vers >= NFS_VER4) && nfs_mount_state_error_should_restart(error) && !ISSET(bp->nb_flags, NB_ERROR)) {
3133 lck_mtx_lock(&nmp->nm_lock);
3134 if ((error != NFSERR_OLD_STATEID) && (error != NFSERR_GRACE) && (cb.rcb_args.stategenid == nmp->nm_stategenid)) {
3135 NP(np, "nfs_buf_write_rpc_finish: error %d @ 0x%llx, 0x%x 0x%x, initiating recovery",
3136 error, NBOFF(bp) + offset, cb.rcb_args.stategenid, nmp->nm_stategenid);
3137 nfs_need_recover(nmp, error);
3138 }
3139 lck_mtx_unlock(&nmp->nm_lock);
3140 if (np->n_flag & NREVOKE) {
3141 error = EIO;
3142 } else {
3143 if (error == NFSERR_GRACE) {
3144 if (cb.rcb_func) {
3145 /*
3146 * For an async I/O request, handle a grace delay just like
3147 * jukebox errors. Set the resend time and queue it up.
3148 */
3149 struct timeval now;
3150 if (req->r_nmrep.nmc_mhead) {
3151 mbuf_freem(req->r_nmrep.nmc_mhead);
3152 req->r_nmrep.nmc_mhead = NULL;
3153 }
3154 req->r_error = 0;
3155 microuptime(&now);
3156 lck_mtx_lock(&req->r_mtx);
3157 req->r_resendtime = now.tv_sec + 2;
3158 req->r_xid = 0; // get a new XID
3159 req->r_flags |= R_RESTART;
3160 req->r_start = 0;
3161 nfs_asyncio_resend(req);
3162 lck_mtx_unlock(&req->r_mtx);
3163 if (IS_VALID_CRED(cred)) {
3164 kauth_cred_unref(&cred);
3165 }
3166 /* Note: nfsreq reference taken will be dropped later when finished */
3167 return;
3168 }
3169 /* otherwise, just pause a couple seconds and retry */
3170 tsleep(&nmp->nm_state, (PZERO - 1), "nfsgrace", 2 * hz);
3171 }
3172 if (!(error = nfs_mount_state_wait_for_recovery(nmp))) {
3173 rlen = 0;
3174 goto writeagain;
3175 }
3176 }
3177 }
3178 #endif
3179 if (error) {
3180 SET(bp->nb_flags, NB_ERROR);
3181 bp->nb_error = error;
3182 }
3183 if (error || (nfsvers == NFS_VER2)) {
3184 goto out;
3185 }
3186 if (rlen <= 0) {
3187 SET(bp->nb_flags, NB_ERROR);
3188 bp->nb_error = error = EIO;
3189 goto out;
3190 }
3191
3192 /* save lowest commit level returned */
3193 if (committed < bp->nb_commitlevel) {
3194 bp->nb_commitlevel = committed;
3195 }
3196
3197 /* check the write verifier */
3198 if (!bp->nb_verf) {
3199 bp->nb_verf = wverf;
3200 } else if (bp->nb_verf != wverf) {
3201 /* verifier changed, so buffer will need to be rewritten */
3202 bp->nb_flags |= NB_STALEWVERF;
3203 bp->nb_commitlevel = NFS_WRITE_UNSTABLE;
3204 bp->nb_verf = wverf;
3205 }
3206
3207 if ((rlen > 0) && (bp->nb_offio < (offset + (int)rlen))) {
3208 bp->nb_offio = offset + rlen;
3209 }
3210
3211 /*
3212 * check for a short write
3213 *
3214 * If the server didn't write all the data, then we
3215 * need to issue another write for the rest of it.
3216 * (Don't bother if the buffer hit an error or stale wverf.)
3217 */
3218 if ((rlen < length) && !(bp->nb_flags & (NB_STALEWVERF | NB_ERROR))) {
3219 #if CONFIG_NFS4
3220 writeagain:
3221 #endif
3222 offset += rlen;
3223 length -= rlen;
3224
3225 auio = uio_createwithbuffer(1, NBOFF(bp) + offset, UIO_SYSSPACE,
3226 UIO_WRITE, &uio_buf, sizeof(uio_buf));
3227 uio_addiov(auio, CAST_USER_ADDR_T(bp->nb_data + offset), length);
3228
3229 cb.rcb_args.offset = offset;
3230 cb.rcb_args.length = length;
3231 #if CONFIG_NFS4
3232 if (nmp->nm_vers >= NFS_VER4) {
3233 cb.rcb_args.stategenid = nmp->nm_stategenid;
3234 }
3235 #endif
3236 // XXX iomode should really match the original request
3237 error = nmp->nm_funcs->nf_write_rpc_async(np, auio, length, thd, cred,
3238 NFS_WRITE_FILESYNC, &cb, &wreq);
3239 if (!error) {
3240 if (IS_VALID_CRED(cred)) {
3241 kauth_cred_unref(&cred);
3242 }
3243 if (!cb.rcb_func) {
3244 /* if !async we'll need to wait for this RPC to finish */
3245 req = wreq;
3246 wreq = NULL;
3247 goto finish;
3248 }
3249 nfs_request_rele(req);
3250 /*
3251 * We're done here.
3252 * Outstanding RPC count is unchanged.
3253 * Callback will be called when RPC is done.
3254 */
3255 return;
3256 }
3257 SET(bp->nb_flags, NB_ERROR);
3258 bp->nb_error = error;
3259 }
3260
3261 out:
3262 if (cb.rcb_func) {
3263 nfs_async_write_done(nmp);
3264 nfs_request_rele(req);
3265 }
3266 /*
3267 * Decrement outstanding RPC count on buffer
3268 * and call nfs_buf_write_finish on last RPC.
3269 *
3270 * (Note: when there are multiple async RPCs issued for a
3271 * buffer we need nfs_buffer_mutex to avoid problems when
3272 * aborting a partially-initiated set of RPCs)
3273 */
3274 multasyncrpc = ISSET(bp->nb_flags, NB_MULTASYNCRPC);
3275 if (multasyncrpc) {
3276 lck_mtx_lock(nfs_buf_mutex);
3277 }
3278
3279 bp->nb_rpcs--;
3280 finished = (bp->nb_rpcs == 0);
3281
3282 if (multasyncrpc) {
3283 lck_mtx_unlock(nfs_buf_mutex);
3284 }
3285
3286 if (finished) {
3287 if (multasyncrpc) {
3288 wakeme = &bp->nb_rpcs;
3289 }
3290 nfs_buf_write_finish(bp, thd, cred);
3291 if (wakeme) {
3292 wakeup(wakeme);
3293 }
3294 }
3295
3296 if (IS_VALID_CRED(cred)) {
3297 kauth_cred_unref(&cred);
3298 }
3299
3300 if (cb.rcb_func && np->n_needcommitcnt >= NFS_A_LOT_OF_NEEDCOMMITS) {
3301 nfs_flushcommits(np, 1);
3302 }
3303 }
3304
3305 /*
3306 * Send commit(s) for the given node's "needcommit" buffers
3307 */
3308 int
3309 nfs_flushcommits(nfsnode_t np, int nowait)
3310 {
3311 struct nfsmount *nmp;
3312 struct nfsbuf *bp, *prevlbp, *lbp;
3313 struct nfsbuflists blist, commitlist;
3314 int error = 0, retv, wcred_set, flags;
3315 u_quad_t off, endoff, toff;
3316 uint64_t wverf, count;
3317 kauth_cred_t wcred = NULL;
3318 nfsbufpgs dirty;
3319
3320 FSDBG_TOP(557, np, 0, 0, 0);
3321
3322 /*
3323 * A nb_flags == (NB_DELWRI | NB_NEEDCOMMIT) block has been written to the
3324 * server, but nas not been committed to stable storage on the server
3325 * yet. The byte range is worked out for as many nfsbufs as we can handle
3326 * and the commit rpc is done.
3327 */
3328 if (!LIST_EMPTY(&np->n_dirtyblkhd)) {
3329 error = nfs_node_lock(np);
3330 if (error) {
3331 goto done;
3332 }
3333 np->n_flag |= NMODIFIED;
3334 nfs_node_unlock(np);
3335 }
3336
3337 off = (u_quad_t)-1;
3338 endoff = 0;
3339 wcred_set = 0;
3340 LIST_INIT(&commitlist);
3341
3342 nmp = NFSTONMP(np);
3343 if (nfs_mount_gone(nmp)) {
3344 error = ENXIO;
3345 goto done;
3346 }
3347 if (nmp->nm_vers == NFS_VER2) {
3348 error = EINVAL;
3349 goto done;
3350 }
3351
3352 flags = NBI_DIRTY;
3353 if (nowait) {
3354 flags |= NBI_NOWAIT;
3355 }
3356 lck_mtx_lock(nfs_buf_mutex);
3357 wverf = nmp->nm_verf;
3358 if (!nfs_buf_iterprepare(np, &blist, flags)) {
3359 while ((bp = LIST_FIRST(&blist))) {
3360 LIST_REMOVE(bp, nb_vnbufs);
3361 LIST_INSERT_HEAD(&np->n_dirtyblkhd, bp, nb_vnbufs);
3362 error = nfs_buf_acquire(bp, NBAC_NOWAIT, 0, 0);
3363 if (error) {
3364 continue;
3365 }
3366 if (ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
3367 nfs_buf_check_write_verifier(np, bp);
3368 }
3369 if (((bp->nb_flags & (NB_DELWRI | NB_NEEDCOMMIT)) != (NB_DELWRI | NB_NEEDCOMMIT)) ||
3370 (bp->nb_verf != wverf)) {
3371 nfs_buf_drop(bp);
3372 continue;
3373 }
3374 nfs_buf_remfree(bp);
3375
3376 /* buffer UPLs will be grabbed *in order* below */
3377
3378 FSDBG(557, bp, bp->nb_flags, bp->nb_valid, bp->nb_dirty);
3379 FSDBG(557, bp->nb_validoff, bp->nb_validend,
3380 bp->nb_dirtyoff, bp->nb_dirtyend);
3381
3382 /*
3383 * Work out if all buffers are using the same cred
3384 * so we can deal with them all with one commit.
3385 *
3386 * Note: creds in bp's must be obtained by kauth_cred_ref
3387 * on the same original cred in order for them to be equal.
3388 */
3389 if (wcred_set == 0) {
3390 wcred = bp->nb_wcred;
3391 if (!IS_VALID_CRED(wcred)) {
3392 panic("nfs: needcommit w/out wcred");
3393 }
3394 wcred_set = 1;
3395 } else if ((wcred_set == 1) && wcred != bp->nb_wcred) {
3396 wcred_set = -1;
3397 }
3398 SET(bp->nb_flags, NB_WRITEINPROG);
3399
3400 /*
3401 * Add this buffer to the list of buffers we are committing.
3402 * Buffers are inserted into the list in ascending order so that
3403 * we can take the UPLs in order after the list is complete.
3404 */
3405 prevlbp = NULL;
3406 LIST_FOREACH(lbp, &commitlist, nb_vnbufs) {
3407 if (bp->nb_lblkno < lbp->nb_lblkno) {
3408 break;
3409 }
3410 prevlbp = lbp;
3411 }
3412 LIST_REMOVE(bp, nb_vnbufs);
3413 if (prevlbp) {
3414 LIST_INSERT_AFTER(prevlbp, bp, nb_vnbufs);
3415 } else {
3416 LIST_INSERT_HEAD(&commitlist, bp, nb_vnbufs);
3417 }
3418
3419 /* update commit range start, end */
3420 toff = NBOFF(bp) + bp->nb_dirtyoff;
3421 if (toff < off) {
3422 off = toff;
3423 }
3424 toff += (u_quad_t)(bp->nb_dirtyend - bp->nb_dirtyoff);
3425 if (toff > endoff) {
3426 endoff = toff;
3427 }
3428 }
3429 nfs_buf_itercomplete(np, &blist, NBI_DIRTY);
3430 }
3431 lck_mtx_unlock(nfs_buf_mutex);
3432
3433 if (LIST_EMPTY(&commitlist)) {
3434 error = ENOBUFS;
3435 goto done;
3436 }
3437
3438 /*
3439 * We need a UPL to prevent others from accessing the buffers during
3440 * our commit RPC(s).
3441 *
3442 * We used to also check for dirty pages here; if there were any we'd
3443 * abort the commit and force the entire buffer to be written again.
3444 * Instead of doing that, we just go ahead and commit the dirty range,
3445 * and then leave the buffer around with dirty pages that will be
3446 * written out later.
3447 */
3448 LIST_FOREACH(bp, &commitlist, nb_vnbufs) {
3449 if (!ISSET(bp->nb_flags, NB_PAGELIST)) {
3450 retv = nfs_buf_upl_setup(bp);
3451 if (retv) {
3452 /* Unable to create the UPL, the VM object probably no longer exists. */
3453 printf("nfs_flushcommits: upl create failed %d\n", retv);
3454 NBPGS_ERASE(&bp->nb_valid);
3455 NBPGS_ERASE(&bp->nb_dirty);
3456 }
3457 }
3458 nfs_buf_upl_check(bp);
3459 }
3460
3461 /*
3462 * Commit data on the server, as required.
3463 * If all bufs are using the same wcred, then use that with
3464 * one call for all of them, otherwise commit each one
3465 * separately.
3466 */
3467 if (wcred_set == 1) {
3468 /*
3469 * Note, it's possible the commit range could be >2^32-1.
3470 * If it is, we'll send one commit that covers the whole file.
3471 */
3472 if ((endoff - off) > 0xffffffff) {
3473 count = 0;
3474 } else {
3475 count = (endoff - off);
3476 }
3477 retv = nmp->nm_funcs->nf_commit_rpc(np, off, count, wcred, wverf);
3478 } else {
3479 retv = 0;
3480 LIST_FOREACH(bp, &commitlist, nb_vnbufs) {
3481 toff = NBOFF(bp) + bp->nb_dirtyoff;
3482 count = bp->nb_dirtyend - bp->nb_dirtyoff;
3483 retv = nmp->nm_funcs->nf_commit_rpc(np, toff, count, bp->nb_wcred, wverf);
3484 if (retv) {
3485 break;
3486 }
3487 }
3488 }
3489
3490 /*
3491 * Now, either mark the blocks I/O done or mark the
3492 * blocks dirty, depending on whether the commit
3493 * succeeded.
3494 */
3495 while ((bp = LIST_FIRST(&commitlist))) {
3496 LIST_REMOVE(bp, nb_vnbufs);
3497 FSDBG(557, bp, retv, bp->nb_flags, bp->nb_dirty);
3498 nfs_node_lock_force(np);
3499 CLR(bp->nb_flags, (NB_NEEDCOMMIT | NB_WRITEINPROG));
3500 np->n_needcommitcnt--;
3501 CHECK_NEEDCOMMITCNT(np);
3502 nfs_node_unlock(np);
3503
3504 if (retv) {
3505 /* move back to dirty list */
3506 lck_mtx_lock(nfs_buf_mutex);
3507 LIST_INSERT_HEAD(&np->n_dirtyblkhd, bp, nb_vnbufs);
3508 lck_mtx_unlock(nfs_buf_mutex);
3509 nfs_buf_release(bp, 1);
3510 continue;
3511 }
3512
3513 nfs_node_lock_force(np);
3514 np->n_numoutput++;
3515 nfs_node_unlock(np);
3516 vnode_startwrite(NFSTOV(np));
3517 if (ISSET(bp->nb_flags, NB_DELWRI)) {
3518 lck_mtx_lock(nfs_buf_mutex);
3519 nfs_nbdwrite--;
3520 NFSBUFCNTCHK();
3521 lck_mtx_unlock(nfs_buf_mutex);
3522 wakeup(&nfs_nbdwrite);
3523 }
3524 CLR(bp->nb_flags, (NB_READ | NB_DONE | NB_ERROR | NB_DELWRI));
3525 /* if block still has dirty pages, we don't want it to */
3526 /* be released in nfs_buf_iodone(). So, don't set NB_ASYNC. */
3527 NBPGS_COPY(&dirty, &bp->nb_dirty);
3528 if (!nfs_buf_pgs_is_set(&dirty)) {
3529 SET(bp->nb_flags, NB_ASYNC);
3530 } else {
3531 CLR(bp->nb_flags, NB_ASYNC);
3532 }
3533
3534 /* move to clean list */
3535 lck_mtx_lock(nfs_buf_mutex);
3536 LIST_INSERT_HEAD(&np->n_cleanblkhd, bp, nb_vnbufs);
3537 lck_mtx_unlock(nfs_buf_mutex);
3538
3539 bp->nb_dirtyoff = bp->nb_dirtyend = 0;
3540
3541 nfs_buf_iodone(bp);
3542 if (nfs_buf_pgs_is_set(&dirty)) {
3543 /* throw it back in as a delayed write buffer */
3544 CLR(bp->nb_flags, NB_DONE);
3545 nfs_buf_write_delayed(bp);
3546 }
3547 }
3548
3549 done:
3550 FSDBG_BOT(557, np, 0, 0, error);
3551 return error;
3552 }
3553
3554 /*
3555 * Flush all the blocks associated with a vnode.
3556 * Walk through the buffer pool and push any dirty pages
3557 * associated with the vnode.
3558 */
3559 int
3560 nfs_flush(nfsnode_t np, int waitfor, thread_t thd, int ignore_writeerr)
3561 {
3562 struct nfsbuf *bp;
3563 struct nfsbuflists blist;
3564 struct nfsmount *nmp = NFSTONMP(np);
3565 int error = 0, error2, slptimeo = 0, slpflag = 0;
3566 int nfsvers, flags, passone = 1;
3567
3568 FSDBG_TOP(517, np, waitfor, ignore_writeerr, 0);
3569
3570 if (nfs_mount_gone(nmp)) {
3571 error = ENXIO;
3572 goto out;
3573 }
3574 nfsvers = nmp->nm_vers;
3575 if (NMFLAG(nmp, INTR)) {
3576 slpflag = PCATCH;
3577 }
3578
3579 if (!LIST_EMPTY(&np->n_dirtyblkhd)) {
3580 nfs_node_lock_force(np);
3581 np->n_flag |= NMODIFIED;
3582 nfs_node_unlock(np);
3583 }
3584
3585 lck_mtx_lock(nfs_buf_mutex);
3586 while (np->n_bflag & NBFLUSHINPROG) {
3587 np->n_bflag |= NBFLUSHWANT;
3588 error = msleep(&np->n_bflag, nfs_buf_mutex, slpflag, "nfs_flush", NULL);
3589 if ((error && (error != EWOULDBLOCK)) ||
3590 ((error = nfs_sigintr(NFSTONMP(np), NULL, thd, 0)))) {
3591 lck_mtx_unlock(nfs_buf_mutex);
3592 goto out;
3593 }
3594 }
3595 np->n_bflag |= NBFLUSHINPROG;
3596
3597 /*
3598 * On the first pass, start async/unstable writes on all
3599 * delayed write buffers. Then wait for all writes to complete
3600 * and call nfs_flushcommits() to commit any uncommitted buffers.
3601 * On all subsequent passes, start STABLE writes on any remaining
3602 * dirty buffers. Then wait for all writes to complete.
3603 */
3604 again:
3605 FSDBG(518, LIST_FIRST(&np->n_dirtyblkhd), np->n_flag, 0, 0);
3606 if (!NFSTONMP(np)) {
3607 lck_mtx_unlock(nfs_buf_mutex);
3608 error = ENXIO;
3609 goto done;
3610 }
3611
3612 /* Start/do any write(s) that are required. */
3613 if (!nfs_buf_iterprepare(np, &blist, NBI_DIRTY)) {
3614 while ((bp = LIST_FIRST(&blist))) {
3615 LIST_REMOVE(bp, nb_vnbufs);
3616 LIST_INSERT_HEAD(&np->n_dirtyblkhd, bp, nb_vnbufs);
3617 flags = (passone || !(waitfor == MNT_WAIT || waitfor == MNT_DWAIT)) ? NBAC_NOWAIT : 0;
3618 if (flags != NBAC_NOWAIT) {
3619 nfs_buf_refget(bp);
3620 }
3621 while ((error = nfs_buf_acquire(bp, flags, slpflag, slptimeo))) {
3622 FSDBG(524, bp, flags, bp->nb_lflags, bp->nb_flags);
3623 if (error == EBUSY) {
3624 break;
3625 }
3626 if (error) {
3627 error2 = nfs_sigintr(NFSTONMP(np), NULL, thd, 0);
3628 if (error2) {
3629 if (flags != NBAC_NOWAIT) {
3630 nfs_buf_refrele(bp);
3631 }
3632 nfs_buf_itercomplete(np, &blist, NBI_DIRTY);
3633 lck_mtx_unlock(nfs_buf_mutex);
3634 error = error2;
3635 goto done;
3636 }
3637 if (slpflag == PCATCH) {
3638 slpflag = 0;
3639 slptimeo = 2 * hz;
3640 }
3641 }
3642 }
3643 if (flags != NBAC_NOWAIT) {
3644 nfs_buf_refrele(bp);
3645 }
3646 if (error == EBUSY) {
3647 continue;
3648 }
3649 if (!bp->nb_np) {
3650 /* buffer is no longer valid */
3651 nfs_buf_drop(bp);
3652 continue;
3653 }
3654 if (ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
3655 nfs_buf_check_write_verifier(np, bp);
3656 }
3657 if (!ISSET(bp->nb_flags, NB_DELWRI)) {
3658 /* buffer is no longer dirty */
3659 nfs_buf_drop(bp);
3660 continue;
3661 }
3662 FSDBG(525, bp, passone, bp->nb_lflags, bp->nb_flags);
3663 if ((passone || !(waitfor == MNT_WAIT || waitfor == MNT_DWAIT)) &&
3664 ISSET(bp->nb_flags, NB_NEEDCOMMIT)) {
3665 nfs_buf_drop(bp);
3666 continue;
3667 }
3668 nfs_buf_remfree(bp);
3669 lck_mtx_unlock(nfs_buf_mutex);
3670 if (ISSET(bp->nb_flags, NB_ERROR)) {
3671 nfs_node_lock_force(np);
3672 np->n_error = bp->nb_error ? bp->nb_error : EIO;
3673 np->n_flag |= NWRITEERR;
3674 nfs_node_unlock(np);
3675 nfs_buf_release(bp, 1);
3676 lck_mtx_lock(nfs_buf_mutex);
3677 continue;
3678 }
3679 SET(bp->nb_flags, NB_ASYNC);
3680 if (!passone) {
3681 /* NB_STABLE forces this to be written FILESYNC */
3682 SET(bp->nb_flags, NB_STABLE);
3683 }
3684 nfs_buf_write(bp);
3685 lck_mtx_lock(nfs_buf_mutex);
3686 }
3687 nfs_buf_itercomplete(np, &blist, NBI_DIRTY);
3688 }
3689 lck_mtx_unlock(nfs_buf_mutex);
3690
3691 if (waitfor == MNT_WAIT || waitfor == MNT_DWAIT) {
3692 while ((error = vnode_waitforwrites(NFSTOV(np), 0, slpflag, slptimeo, "nfsflush"))) {
3693 error2 = nfs_sigintr(NFSTONMP(np), NULL, thd, 0);
3694 if (error2) {
3695 error = error2;
3696 goto done;
3697 }
3698 if (slpflag == PCATCH) {
3699 slpflag = 0;
3700 slptimeo = 2 * hz;
3701 }
3702 }
3703 }
3704
3705 if (nfsvers != NFS_VER2) {
3706 /* loop while it looks like there are still buffers to be */
3707 /* commited and nfs_flushcommits() seems to be handling them. */
3708 while (np->n_needcommitcnt) {
3709 if (nfs_flushcommits(np, 0)) {
3710 break;
3711 }
3712 }
3713 }
3714
3715 if (passone) {
3716 passone = 0;
3717 if (!LIST_EMPTY(&np->n_dirtyblkhd)) {
3718 nfs_node_lock_force(np);
3719 np->n_flag |= NMODIFIED;
3720 nfs_node_unlock(np);
3721 }
3722 lck_mtx_lock(nfs_buf_mutex);
3723 goto again;
3724 }
3725
3726 if (waitfor == MNT_WAIT || waitfor == MNT_DWAIT) {
3727 if (!LIST_EMPTY(&np->n_dirtyblkhd)) {
3728 nfs_node_lock_force(np);
3729 np->n_flag |= NMODIFIED;
3730 nfs_node_unlock(np);
3731 }
3732 lck_mtx_lock(nfs_buf_mutex);
3733 if (!LIST_EMPTY(&np->n_dirtyblkhd)) {
3734 goto again;
3735 }
3736 lck_mtx_unlock(nfs_buf_mutex);
3737 nfs_node_lock_force(np);
3738 /*
3739 * OK, it looks like there are no dirty blocks. If we have no
3740 * writes in flight and no one in the write code, we can clear
3741 * the modified flag. In order to make sure we see the latest
3742 * attributes and size, we also invalidate the attributes and
3743 * advance the attribute cache XID to guarantee that attributes
3744 * newer than our clearing of NMODIFIED will get loaded next.
3745 * (If we don't do this, it's possible for the flush's final
3746 * write/commit (xid1) to be executed in parallel with a subsequent
3747 * getattr request (xid2). The getattr could return attributes
3748 * from *before* the write/commit completed but the stale attributes
3749 * would be preferred because of the xid ordering.)
3750 */
3751 if (!np->n_wrbusy && !np->n_numoutput) {
3752 np->n_flag &= ~NMODIFIED;
3753 NATTRINVALIDATE(np);
3754 nfs_get_xid(&np->n_xid);
3755 }
3756 } else {
3757 nfs_node_lock_force(np);
3758 }
3759
3760 FSDBG(526, np->n_flag, np->n_error, 0, 0);
3761 if (!ignore_writeerr && (np->n_flag & NWRITEERR)) {
3762 error = np->n_error;
3763 np->n_flag &= ~NWRITEERR;
3764 }
3765 nfs_node_unlock(np);
3766 done:
3767 lck_mtx_lock(nfs_buf_mutex);
3768 flags = np->n_bflag;
3769 np->n_bflag &= ~(NBFLUSHINPROG | NBFLUSHWANT);
3770 lck_mtx_unlock(nfs_buf_mutex);
3771 if (flags & NBFLUSHWANT) {
3772 wakeup(&np->n_bflag);
3773 }
3774 out:
3775 FSDBG_BOT(517, np, error, ignore_writeerr, 0);
3776 return error;
3777 }
3778
3779 /*
3780 * Flush out and invalidate all buffers associated with a vnode.
3781 * Called with the underlying object locked.
3782 */
3783 int
3784 nfs_vinvalbuf_internal(
3785 nfsnode_t np,
3786 int flags,
3787 thread_t thd,
3788 kauth_cred_t cred,
3789 int slpflag,
3790 int slptimeo)
3791 {
3792 struct nfsbuf *bp;
3793 struct nfsbuflists blist;
3794 int list, error = 0;
3795
3796 if (flags & V_SAVE) {
3797 if ((error = nfs_flush(np, MNT_WAIT, thd, (flags & V_IGNORE_WRITEERR)))) {
3798 return error;
3799 }
3800 }
3801
3802 lck_mtx_lock(nfs_buf_mutex);
3803 for (;;) {
3804 list = NBI_CLEAN;
3805 if (nfs_buf_iterprepare(np, &blist, list)) {
3806 list = NBI_DIRTY;
3807 if (nfs_buf_iterprepare(np, &blist, list)) {
3808 break;
3809 }
3810 }
3811 while ((bp = LIST_FIRST(&blist))) {
3812 LIST_REMOVE(bp, nb_vnbufs);
3813 if (list == NBI_CLEAN) {
3814 LIST_INSERT_HEAD(&np->n_cleanblkhd, bp, nb_vnbufs);
3815 } else {
3816 LIST_INSERT_HEAD(&np->n_dirtyblkhd, bp, nb_vnbufs);
3817 }
3818 nfs_buf_refget(bp);
3819 while ((error = nfs_buf_acquire(bp, NBAC_REMOVE, slpflag, slptimeo))) {
3820 FSDBG(556, np, bp, NBOFF(bp), bp->nb_flags);
3821 if (error != EAGAIN) {
3822 FSDBG(554, np, bp, -1, error);
3823 nfs_buf_refrele(bp);
3824 nfs_buf_itercomplete(np, &blist, list);
3825 lck_mtx_unlock(nfs_buf_mutex);
3826 return error;
3827 }
3828 }
3829 nfs_buf_refrele(bp);
3830 FSDBG(554, np, bp, NBOFF(bp), bp->nb_flags);
3831 lck_mtx_unlock(nfs_buf_mutex);
3832 if ((flags & V_SAVE) && UBCINFOEXISTS(NFSTOV(np)) && bp->nb_np &&
3833 (NBOFF(bp) < (off_t)np->n_size)) {
3834 /* extra paranoia: make sure we're not */
3835 /* somehow leaving any dirty data around */
3836 nfsbufpgs pagemask;
3837 int mustwrite = 0;
3838 off_t end = (NBOFF(bp) + bp->nb_bufsize > (off_t)np->n_size) ?
3839 (np->n_size - NBOFF(bp)) : bp->nb_bufsize;
3840 if (!ISSET(bp->nb_flags, NB_PAGELIST)) {
3841 error = nfs_buf_upl_setup(bp);
3842 if (error == EINVAL) {
3843 /* vm object must no longer exist */
3844 /* hopefully we don't need to do */
3845 /* anything for this buffer */
3846 } else if (error) {
3847 printf("nfs_vinvalbuf: upl setup failed %d\n", error);
3848 }
3849 NBPGS_ERASE(&bp->nb_valid);
3850 NBPGS_ERASE(&bp->nb_dirty);
3851 }
3852 nfs_buf_upl_check(bp);
3853 /* check for any dirty data before the EOF */
3854 if ((bp->nb_dirtyend > 0) && (bp->nb_dirtyoff < end)) {
3855 /* clip dirty range to EOF */
3856 if (bp->nb_dirtyend > end) {
3857 bp->nb_dirtyend = end;
3858 if (bp->nb_dirtyoff >= bp->nb_dirtyend) {
3859 bp->nb_dirtyoff = bp->nb_dirtyend = 0;
3860 }
3861 }
3862 if ((bp->nb_dirtyend > 0) && (bp->nb_dirtyoff < end)) {
3863 mustwrite++;
3864 }
3865 }
3866 nfs_buf_pgs_get_page_mask(&pagemask, round_page_64(end) / PAGE_SIZE);
3867 nfs_buf_pgs_bit_and(&bp->nb_dirty, &pagemask, &bp->nb_dirty);
3868 if (nfs_buf_pgs_is_set(&bp->nb_dirty)) {
3869 mustwrite++;
3870 }
3871 /* also make sure we'll have a credential to do the write */
3872 if (mustwrite && !IS_VALID_CRED(bp->nb_wcred) && !IS_VALID_CRED(cred)) {
3873 printf("nfs_vinvalbuf: found dirty buffer with no write creds\n");
3874 mustwrite = 0;
3875 }
3876 if (mustwrite) {
3877 FSDBG(554, np, bp, 0xd00dee, bp->nb_flags);
3878 if (!ISSET(bp->nb_flags, NB_PAGELIST)) {
3879 panic("nfs_vinvalbuf: dirty buffer without upl");
3880 }
3881 /* gotta write out dirty data before invalidating */
3882 /* (NB_STABLE indicates that data writes should be FILESYNC) */
3883 /* (NB_NOCACHE indicates buffer should be discarded) */
3884 CLR(bp->nb_flags, (NB_DONE | NB_ERROR | NB_INVAL | NB_ASYNC));
3885 SET(bp->nb_flags, NB_STABLE | NB_NOCACHE);
3886 if (!IS_VALID_CRED(bp->nb_wcred)) {
3887 kauth_cred_ref(cred);
3888 bp->nb_wcred = cred;
3889 }
3890 error = nfs_buf_write(bp);
3891 // Note: bp has been released
3892 if (error) {
3893 FSDBG(554, bp, 0xd00dee, 0xbad, error);
3894 nfs_node_lock_force(np);
3895 if ((error != EINTR) && (error != ERESTART)) {
3896 np->n_error = error;
3897 np->n_flag |= NWRITEERR;
3898 }
3899 /*
3900 * There was a write error and we need to
3901 * invalidate attrs to sync with server.
3902 * (if this write was extending the file,
3903 * we may no longer know the correct size)
3904 */
3905 NATTRINVALIDATE(np);
3906 nfs_node_unlock(np);
3907 if ((error == EINTR) || (error == ERESTART)) {
3908 /*
3909 * Abort on EINTR. If we don't, we could
3910 * be stuck in this loop forever because
3911 * the buffer will continue to stay dirty.
3912 */
3913 lck_mtx_lock(nfs_buf_mutex);
3914 nfs_buf_itercomplete(np, &blist, list);
3915 lck_mtx_unlock(nfs_buf_mutex);
3916 return error;
3917 }
3918 error = 0;
3919 }
3920 lck_mtx_lock(nfs_buf_mutex);
3921 continue;
3922 }
3923 }
3924 SET(bp->nb_flags, NB_INVAL);
3925 // hold off on FREEUPs until we're done here
3926 nfs_buf_release(bp, 0);
3927 lck_mtx_lock(nfs_buf_mutex);
3928 }
3929 nfs_buf_itercomplete(np, &blist, list);
3930 }
3931 if (!LIST_EMPTY(&(np)->n_dirtyblkhd) || !LIST_EMPTY(&(np)->n_cleanblkhd)) {
3932 panic("nfs_vinvalbuf: flush/inval failed");
3933 }
3934 lck_mtx_unlock(nfs_buf_mutex);
3935 nfs_node_lock_force(np);
3936 if (!(flags & V_SAVE)) {
3937 np->n_flag &= ~NMODIFIED;
3938 }
3939 if (vnode_vtype(NFSTOV(np)) == VREG) {
3940 np->n_lastrahead = -1;
3941 }
3942 nfs_node_unlock(np);
3943 NFS_BUF_FREEUP();
3944 return 0;
3945 }
3946
3947
3948 /*
3949 * Flush and invalidate all dirty buffers. If another process is already
3950 * doing the flush, just wait for completion.
3951 */
3952 int
3953 nfs_vinvalbuf(vnode_t vp, int flags, vfs_context_t ctx, int intrflg)
3954 {
3955 return nfs_vinvalbuf2(vp, flags, vfs_context_thread(ctx), vfs_context_ucred(ctx), intrflg);
3956 }
3957
3958 int
3959 nfs_vinvalbuf2(vnode_t vp, int flags, thread_t thd, kauth_cred_t cred, int intrflg)
3960 {
3961 nfsnode_t np = VTONFS(vp);
3962 struct nfsmount *nmp = VTONMP(vp);
3963 int error, slpflag, slptimeo, nflags, retry = 0;
3964 int ubcflags = UBC_PUSHALL | UBC_SYNC | UBC_INVALIDATE;
3965 struct timespec ts = { .tv_sec = 2, .tv_nsec = 0 };
3966 off_t size;
3967
3968 FSDBG_TOP(554, np, flags, intrflg, 0);
3969
3970 /*
3971 * If the mount is gone no sense to try and write anything.
3972 * and hang trying to do IO.
3973 */
3974 if (nfs_mount_gone(nmp)) {
3975 flags &= ~V_SAVE;
3976 ubcflags &= ~UBC_PUSHALL;
3977 }
3978
3979 if (nmp && !NMFLAG(nmp, INTR)) {
3980 intrflg = 0;
3981 }
3982 if (intrflg) {
3983 slpflag = PCATCH;
3984 slptimeo = 2 * hz;
3985 } else {
3986 slpflag = 0;
3987 slptimeo = 0;
3988 }
3989
3990 /* First wait for any other process doing a flush to complete. */
3991 lck_mtx_lock(nfs_buf_mutex);
3992 while (np->n_bflag & NBINVALINPROG) {
3993 np->n_bflag |= NBINVALWANT;
3994 msleep(&np->n_bflag, nfs_buf_mutex, slpflag, "nfs_vinvalbuf", &ts);
3995 if ((error = nfs_sigintr(VTONMP(vp), NULL, thd, 0))) {
3996 lck_mtx_unlock(nfs_buf_mutex);
3997 return error;
3998 }
3999 if (np->n_bflag & NBINVALINPROG) {
4000 slpflag = 0;
4001 }
4002 }
4003 np->n_bflag |= NBINVALINPROG;
4004 lck_mtx_unlock(nfs_buf_mutex);
4005
4006 /* Now, flush as required. */
4007 again:
4008 error = nfs_vinvalbuf_internal(np, flags, thd, cred, slpflag, 0);
4009 while (error) {
4010 FSDBG(554, np, 0, 0, error);
4011 if ((error = nfs_sigintr(VTONMP(vp), NULL, thd, 0))) {
4012 goto done;
4013 }
4014 error = nfs_vinvalbuf_internal(np, flags, thd, cred, 0, slptimeo);
4015 }
4016
4017 /* get the pages out of vm also */
4018 if (UBCINFOEXISTS(vp) && (size = ubc_getsize(vp))) {
4019 if ((error = ubc_msync(vp, 0, size, NULL, ubcflags))) {
4020 if (error == EINVAL) {
4021 panic("nfs_vinvalbuf(): ubc_msync failed!, error %d", error);
4022 }
4023 if (retry++ < 10) { /* retry invalidating a few times */
4024 if (retry > 1 || error == ENXIO) {
4025 ubcflags &= ~UBC_PUSHALL;
4026 }
4027 goto again;
4028 }
4029 /* give up */
4030 printf("nfs_vinvalbuf(): ubc_msync failed!, error %d\n", error);
4031 }
4032 }
4033 done:
4034 lck_mtx_lock(nfs_buf_mutex);
4035 nflags = np->n_bflag;
4036 np->n_bflag &= ~(NBINVALINPROG | NBINVALWANT);
4037 lck_mtx_unlock(nfs_buf_mutex);
4038 if (nflags & NBINVALWANT) {
4039 wakeup(&np->n_bflag);
4040 }
4041
4042 FSDBG_BOT(554, np, flags, intrflg, error);
4043 return error;
4044 }
4045
4046 /*
4047 * Wait for any busy buffers to complete.
4048 */
4049 void
4050 nfs_wait_bufs(nfsnode_t np)
4051 {
4052 struct nfsbuf *bp;
4053 struct nfsbuflists blist;
4054 int error = 0;
4055
4056 lck_mtx_lock(nfs_buf_mutex);
4057 if (!nfs_buf_iterprepare(np, &blist, NBI_CLEAN)) {
4058 while ((bp = LIST_FIRST(&blist))) {
4059 LIST_REMOVE(bp, nb_vnbufs);
4060 LIST_INSERT_HEAD(&np->n_cleanblkhd, bp, nb_vnbufs);
4061 nfs_buf_refget(bp);
4062 while ((error = nfs_buf_acquire(bp, 0, 0, 0))) {
4063 if (error != EAGAIN) {
4064 nfs_buf_refrele(bp);
4065 nfs_buf_itercomplete(np, &blist, NBI_CLEAN);
4066 lck_mtx_unlock(nfs_buf_mutex);
4067 return;
4068 }
4069 }
4070 nfs_buf_refrele(bp);
4071 nfs_buf_drop(bp);
4072 }
4073 nfs_buf_itercomplete(np, &blist, NBI_CLEAN);
4074 }
4075 if (!nfs_buf_iterprepare(np, &blist, NBI_DIRTY)) {
4076 while ((bp = LIST_FIRST(&blist))) {
4077 LIST_REMOVE(bp, nb_vnbufs);
4078 LIST_INSERT_HEAD(&np->n_dirtyblkhd, bp, nb_vnbufs);
4079 nfs_buf_refget(bp);
4080 while ((error = nfs_buf_acquire(bp, 0, 0, 0))) {
4081 if (error != EAGAIN) {
4082 nfs_buf_refrele(bp);
4083 nfs_buf_itercomplete(np, &blist, NBI_DIRTY);
4084 lck_mtx_unlock(nfs_buf_mutex);
4085 return;
4086 }
4087 }
4088 nfs_buf_refrele(bp);
4089 nfs_buf_drop(bp);
4090 }
4091 nfs_buf_itercomplete(np, &blist, NBI_DIRTY);
4092 }
4093 lck_mtx_unlock(nfs_buf_mutex);
4094 }
4095
4096
4097 /*
4098 * Add an async I/O request to the mount's async I/O queue and make
4099 * sure that an nfsiod will service it.
4100 */
4101 void
4102 nfs_asyncio_finish(struct nfsreq *req)
4103 {
4104 struct nfsmount *nmp;
4105 struct nfsiod *niod;
4106 int started = 0;
4107
4108 FSDBG_TOP(552, nmp, 0, 0, 0);
4109 again:
4110 nmp = req->r_nmp;
4111
4112 if (nmp == NULL) {
4113 return;
4114 }
4115
4116 lck_mtx_lock(nfsiod_mutex);
4117 niod = nmp->nm_niod;
4118
4119 /* grab an nfsiod if we don't have one already */
4120 if (!niod) {
4121 niod = TAILQ_FIRST(&nfsiodfree);
4122 if (niod) {
4123 TAILQ_REMOVE(&nfsiodfree, niod, niod_link);
4124 TAILQ_INSERT_TAIL(&nfsiodwork, niod, niod_link);
4125 niod->niod_nmp = nmp;
4126 } else if (((nfsiod_thread_count < NFSIOD_MAX) || (nfsiod_thread_count <= 0)) && (started < 4)) {
4127 /*
4128 * Try starting a new thread.
4129 * We may try a couple times if other callers
4130 * get the new threads before we do.
4131 */
4132 lck_mtx_unlock(nfsiod_mutex);
4133 started++;
4134 if (!nfsiod_start()) {
4135 goto again;
4136 }
4137 lck_mtx_lock(nfsiod_mutex);
4138 }
4139 }
4140
4141 /*
4142 * If we got here while being on the resendq we need to get off. This
4143 * happens when the timer fires and errors out requests from nfs_sigintr
4144 * or we receive a reply (UDP case) while being on the resend queue so
4145 * we're just finishing up and are not going to be resent.
4146 */
4147 lck_mtx_lock(&req->r_mtx);
4148 if (req->r_flags & R_RESENDQ) {
4149 lck_mtx_lock(&nmp->nm_lock);
4150 if ((req->r_flags & R_RESENDQ) && req->r_rchain.tqe_next != NFSREQNOLIST) {
4151 NFS_BIO_DBG("Proccessing async request on resendq. Removing");
4152 TAILQ_REMOVE(&nmp->nm_resendq, req, r_rchain);
4153 req->r_flags &= ~R_RESENDQ;
4154 req->r_rchain.tqe_next = NFSREQNOLIST;
4155 assert(req->r_refs > 1);
4156 /* Remove resendq reference */
4157 req->r_refs--;
4158 }
4159 lck_mtx_unlock(&nmp->nm_lock);
4160 }
4161 lck_mtx_unlock(&req->r_mtx);
4162
4163 if (req->r_achain.tqe_next == NFSREQNOLIST) {
4164 TAILQ_INSERT_TAIL(&nmp->nm_iodq, req, r_achain);
4165 }
4166
4167 /* If this mount doesn't already have an nfsiod working on it... */
4168 if (!nmp->nm_niod) {
4169 if (niod) { /* give it the nfsiod we just grabbed */
4170 nmp->nm_niod = niod;
4171 lck_mtx_unlock(nfsiod_mutex);
4172 wakeup(niod);
4173 } else if (nfsiod_thread_count > 0) {
4174 /* just queue it up on nfsiod mounts queue if needed */
4175 if (nmp->nm_iodlink.tqe_next == NFSNOLIST) {
4176 TAILQ_INSERT_TAIL(&nfsiodmounts, nmp, nm_iodlink);
4177 }
4178 lck_mtx_unlock(nfsiod_mutex);
4179 } else {
4180 printf("nfs_asyncio(): no nfsiods? %d %d (%d)\n", nfsiod_thread_count, NFSIOD_MAX, started);
4181 lck_mtx_unlock(nfsiod_mutex);
4182 /* we have no other option but to be persistent */
4183 started = 0;
4184 goto again;
4185 }
4186 } else {
4187 lck_mtx_unlock(nfsiod_mutex);
4188 }
4189
4190 FSDBG_BOT(552, nmp, 0, 0, 0);
4191 }
4192
4193 /*
4194 * queue up async I/O request for resend
4195 * Must be called with req->r_mtx locked.
4196 */
4197 void
4198 nfs_asyncio_resend(struct nfsreq *req)
4199 {
4200 struct nfsmount *nmp = req->r_nmp;
4201
4202 if (nfs_mount_gone(nmp)) {
4203 return;
4204 }
4205
4206 #if CONFIG_NFS_GSS
4207 nfs_gss_clnt_rpcdone(req);
4208 #endif
4209 lck_mtx_lock(&nmp->nm_lock);
4210 if (!(req->r_flags & R_RESENDQ)) {
4211 TAILQ_INSERT_TAIL(&nmp->nm_resendq, req, r_rchain);
4212 req->r_flags |= R_RESENDQ;
4213 /*
4214 * We take a reference on this request so that it can't be
4215 * destroyed while a resend is queued or in progress.
4216 */
4217 nfs_request_ref(req, 1);
4218 }
4219 nfs_mount_sock_thread_wake(nmp);
4220 lck_mtx_unlock(&nmp->nm_lock);
4221 }
4222
4223 /*
4224 * Read directory data into a buffer.
4225 *
4226 * Buffer will be filled (unless EOF is hit).
4227 * Buffers after this one may also be completely/partially filled.
4228 */
4229 int
4230 nfs_buf_readdir(struct nfsbuf *bp, vfs_context_t ctx)
4231 {
4232 nfsnode_t np = bp->nb_np;
4233 struct nfsmount *nmp = NFSTONMP(np);
4234 int error = 0;
4235
4236 if (nfs_mount_gone(nmp)) {
4237 return ENXIO;
4238 }
4239
4240 if (nmp->nm_vers < NFS_VER4) {
4241 error = nfs3_readdir_rpc(np, bp, ctx);
4242 }
4243 #if CONFIG_NFS4
4244 else {
4245 error = nfs4_readdir_rpc(np, bp, ctx);
4246 }
4247 #endif
4248 if (error && (error != NFSERR_DIRBUFDROPPED)) {
4249 SET(bp->nb_flags, NB_ERROR);
4250 bp->nb_error = error;
4251 }
4252 return error;
4253 }
4254
4255 #endif /* CONFIG_NFS_CLIENT */