1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Rick Macklem at The University of Guelph.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95
35 */
36
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/bio.h>
43 #include <sys/buf.h>
44 #include <sys/kernel.h>
45 #include <sys/mount.h>
46 #include <sys/rwlock.h>
47 #include <sys/vmmeter.h>
48 #include <sys/vnode.h>
49
50 #include <vm/vm.h>
51 #include <vm/vm_param.h>
52 #include <vm/vm_extern.h>
53 #include <vm/vm_page.h>
54 #include <vm/vm_object.h>
55 #include <vm/vm_pager.h>
56 #include <vm/vnode_pager.h>
57
58 #include <fs/nfs/nfsport.h>
59 #include <fs/nfsclient/nfsmount.h>
60 #include <fs/nfsclient/nfs.h>
61 #include <fs/nfsclient/nfsnode.h>
62 #include <fs/nfsclient/nfs_kdtrace.h>
63
64 extern int newnfs_directio_allow_mmap;
65 extern struct nfsstatsv1 nfsstatsv1;
66 extern struct mtx ncl_iod_mutex;
67 extern int ncl_numasync;
68 extern enum nfsiod_state ncl_iodwant[NFS_MAXASYNCDAEMON];
69 extern struct nfsmount *ncl_iodmount[NFS_MAXASYNCDAEMON];
70 extern int newnfs_directio_enable;
71 extern int nfs_keep_dirty_on_error;
72
73 uma_zone_t ncl_pbuf_zone;
74
75 static struct buf *nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size,
76 struct thread *td);
77 static int nfs_directio_write(struct vnode *vp, struct uio *uiop,
78 struct ucred *cred, int ioflag);
79
80 /*
81 * Vnode op for VM getpages.
82 */
83 SYSCTL_DECL(_vfs_nfs);
84 static int use_buf_pager = 1;
85 SYSCTL_INT(_vfs_nfs, OID_AUTO, use_buf_pager, CTLFLAG_RWTUN,
86 &use_buf_pager, 0,
87 "Use buffer pager instead of direct readrpc call");
88
89 static daddr_t
90 ncl_gbp_getblkno(struct vnode *vp, vm_ooffset_t off)
91 {
92
93 return (off / vp->v_bufobj.bo_bsize);
94 }
95
96 static int
97 ncl_gbp_getblksz(struct vnode *vp, daddr_t lbn, long *sz)
98 {
99 struct nfsnode *np;
100 u_quad_t nsize;
101 int biosize, bcount;
102
103 np = VTONFS(vp);
104 NFSLOCKNODE(np);
105 nsize = np->n_size;
106 NFSUNLOCKNODE(np);
107
108 biosize = vp->v_bufobj.bo_bsize;
109 bcount = biosize;
110 if ((off_t)lbn * biosize >= nsize)
111 bcount = 0;
112 else if ((off_t)(lbn + 1) * biosize > nsize)
113 bcount = nsize - (off_t)lbn * biosize;
114 *sz = bcount;
115 return (0);
116 }
117
118 int
119 ncl_getpages(struct vop_getpages_args *ap)
120 {
121 int i, error, nextoff, size, toff, count, npages;
122 struct uio uio;
123 struct iovec iov;
124 vm_offset_t kva;
125 struct buf *bp;
126 struct vnode *vp;
127 struct thread *td;
128 struct ucred *cred;
129 struct nfsmount *nmp;
130 vm_object_t object;
131 vm_page_t *pages;
132 struct nfsnode *np;
133
134 vp = ap->a_vp;
135 np = VTONFS(vp);
136 td = curthread;
137 cred = curthread->td_ucred;
138 nmp = VFSTONFS(vp->v_mount);
139 pages = ap->a_m;
140 npages = ap->a_count;
141
142 if ((object = vp->v_object) == NULL) {
143 printf("ncl_getpages: called with non-merged cache vnode\n");
144 return (VM_PAGER_ERROR);
145 }
146
147 if (newnfs_directio_enable && !newnfs_directio_allow_mmap) {
148 NFSLOCKNODE(np);
149 if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) {
150 NFSUNLOCKNODE(np);
151 printf("ncl_getpages: called on non-cacheable vnode\n");
152 return (VM_PAGER_ERROR);
153 } else
154 NFSUNLOCKNODE(np);
155 }
156
157 mtx_lock(&nmp->nm_mtx);
158 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 &&
159 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) {
160 mtx_unlock(&nmp->nm_mtx);
161 /* We'll never get here for v4, because we always have fsinfo */
162 (void)ncl_fsinfo(nmp, vp, cred, td);
163 } else
164 mtx_unlock(&nmp->nm_mtx);
165
166 if (use_buf_pager)
167 return (vfs_bio_getpages(vp, pages, npages, ap->a_rbehind,
168 ap->a_rahead, ncl_gbp_getblkno, ncl_gbp_getblksz));
169
170 /*
171 * If the requested page is partially valid, just return it and
172 * allow the pager to zero-out the blanks. Partially valid pages
173 * can only occur at the file EOF.
174 *
175 * XXXGL: is that true for NFS, where short read can occur???
176 */
177 VM_OBJECT_WLOCK(object);
178 if (!vm_page_none_valid(pages[npages - 1]) && --npages == 0)
179 goto out;
180 VM_OBJECT_WUNLOCK(object);
181
182 /*
183 * We use only the kva address for the buffer, but this is extremely
184 * convenient and fast.
185 */
186 bp = uma_zalloc(ncl_pbuf_zone, M_WAITOK);
187
188 kva = (vm_offset_t) bp->b_data;
189 pmap_qenter(kva, pages, npages);
190 VM_CNT_INC(v_vnodein);
191 VM_CNT_ADD(v_vnodepgsin, npages);
192
193 count = npages << PAGE_SHIFT;
194 iov.iov_base = (caddr_t) kva;
195 iov.iov_len = count;
196 uio.uio_iov = &iov;
197 uio.uio_iovcnt = 1;
198 uio.uio_offset = IDX_TO_OFF(pages[0]->pindex);
199 uio.uio_resid = count;
200 uio.uio_segflg = UIO_SYSSPACE;
201 uio.uio_rw = UIO_READ;
202 uio.uio_td = td;
203
204 error = ncl_readrpc(vp, &uio, cred);
205 pmap_qremove(kva, npages);
206
207 uma_zfree(ncl_pbuf_zone, bp);
208
209 if (error && (uio.uio_resid == count)) {
210 printf("ncl_getpages: error %d\n", error);
211 return (VM_PAGER_ERROR);
212 }
213
214 /*
215 * Calculate the number of bytes read and validate only that number
216 * of bytes. Note that due to pending writes, size may be 0. This
217 * does not mean that the remaining data is invalid!
218 */
219
220 size = count - uio.uio_resid;
221 VM_OBJECT_WLOCK(object);
222 for (i = 0, toff = 0; i < npages; i++, toff = nextoff) {
223 vm_page_t m;
224 nextoff = toff + PAGE_SIZE;
225 m = pages[i];
226
227 if (nextoff <= size) {
228 /*
229 * Read operation filled an entire page
230 */
231 vm_page_valid(m);
232 KASSERT(m->dirty == 0,
233 ("nfs_getpages: page %p is dirty", m));
234 } else if (size > toff) {
235 /*
236 * Read operation filled a partial page.
237 */
238 vm_page_invalid(m);
239 vm_page_set_valid_range(m, 0, size - toff);
240 KASSERT(m->dirty == 0,
241 ("nfs_getpages: page %p is dirty", m));
242 } else {
243 /*
244 * Read operation was short. If no error
245 * occurred we may have hit a zero-fill
246 * section. We leave valid set to 0, and page
247 * is freed by vm_page_readahead_finish() if
248 * its index is not equal to requested, or
249 * page is zeroed and set valid by
250 * vm_pager_get_pages() for requested page.
251 */
252 ;
253 }
254 }
255 out:
256 VM_OBJECT_WUNLOCK(object);
257 if (ap->a_rbehind)
258 *ap->a_rbehind = 0;
259 if (ap->a_rahead)
260 *ap->a_rahead = 0;
261 return (VM_PAGER_OK);
262 }
263
264 /*
265 * Vnode op for VM putpages.
266 */
267 int
268 ncl_putpages(struct vop_putpages_args *ap)
269 {
270 struct uio uio;
271 struct iovec iov;
272 int i, error, npages, count;
273 off_t offset;
274 int *rtvals;
275 struct vnode *vp;
276 struct thread *td;
277 struct ucred *cred;
278 struct nfsmount *nmp;
279 struct nfsnode *np;
280 vm_page_t *pages;
281
282 vp = ap->a_vp;
283 np = VTONFS(vp);
284 td = curthread; /* XXX */
285 /* Set the cred to n_writecred for the write rpcs. */
286 if (np->n_writecred != NULL)
287 cred = crhold(np->n_writecred);
288 else
289 cred = crhold(curthread->td_ucred); /* XXX */
290 nmp = VFSTONFS(vp->v_mount);
291 pages = ap->a_m;
292 count = ap->a_count;
293 rtvals = ap->a_rtvals;
294 npages = btoc(count);
295 offset = IDX_TO_OFF(pages[0]->pindex);
296
297 mtx_lock(&nmp->nm_mtx);
298 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 &&
299 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) {
300 mtx_unlock(&nmp->nm_mtx);
301 (void)ncl_fsinfo(nmp, vp, cred, td);
302 } else
303 mtx_unlock(&nmp->nm_mtx);
304
305 NFSLOCKNODE(np);
306 if (newnfs_directio_enable && !newnfs_directio_allow_mmap &&
307 (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) {
308 NFSUNLOCKNODE(np);
309 printf("ncl_putpages: called on noncache-able vnode\n");
310 NFSLOCKNODE(np);
311 }
312 /*
313 * When putting pages, do not extend file past EOF.
314 */
315 if (offset + count > np->n_size) {
316 count = np->n_size - offset;
317 if (count < 0)
318 count = 0;
319 }
320 NFSUNLOCKNODE(np);
321
322 for (i = 0; i < npages; i++)
323 rtvals[i] = VM_PAGER_ERROR;
324
325 VM_CNT_INC(v_vnodeout);
326 VM_CNT_ADD(v_vnodepgsout, count);
327
328 iov.iov_base = unmapped_buf;
329 iov.iov_len = count;
330 uio.uio_iov = &iov;
331 uio.uio_iovcnt = 1;
332 uio.uio_offset = offset;
333 uio.uio_resid = count;
334 uio.uio_segflg = UIO_NOCOPY;
335 uio.uio_rw = UIO_WRITE;
336 uio.uio_td = td;
337
338 error = VOP_WRITE(vp, &uio, vnode_pager_putpages_ioflags(ap->a_sync),
339 cred);
340 crfree(cred);
341
342 if (error == 0 || !nfs_keep_dirty_on_error) {
343 vnode_pager_undirty_pages(pages, rtvals, count - uio.uio_resid,
344 np->n_size - offset, npages * PAGE_SIZE);
345 }
346 return (rtvals[0]);
347 }
348
349 /*
350 * For nfs, cache consistency can only be maintained approximately.
351 * Although RFC1094 does not specify the criteria, the following is
352 * believed to be compatible with the reference port.
353 * For nfs:
354 * If the file's modify time on the server has changed since the
355 * last read rpc or you have written to the file,
356 * you may have lost data cache consistency with the
357 * server, so flush all of the file's data out of the cache.
358 * Then force a getattr rpc to ensure that you have up to date
359 * attributes.
360 * NB: This implies that cache data can be read when up to
361 * NFS_ATTRTIMEO seconds out of date. If you find that you need current
362 * attributes this could be forced by setting n_attrstamp to 0 before
363 * the VOP_GETATTR() call.
364 */
365 static inline int
366 nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred)
367 {
368 int error = 0;
369 struct vattr vattr;
370 struct nfsnode *np = VTONFS(vp);
371 bool old_lock;
372
373 /*
374 * Ensure the exclusove access to the node before checking
375 * whether the cache is consistent.
376 */
377 old_lock = ncl_excl_start(vp);
378 NFSLOCKNODE(np);
379 if (np->n_flag & NMODIFIED) {
380 NFSUNLOCKNODE(np);
381 if (vp->v_type != VREG) {
382 if (vp->v_type != VDIR)
383 panic("nfs: bioread, not dir");
384 ncl_invaldir(vp);
385 error = ncl_vinvalbuf(vp, V_SAVE | V_ALLOWCLEAN, td, 1);
386 if (error != 0)
387 goto out;
388 }
389 np->n_attrstamp = 0;
390 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
391 error = VOP_GETATTR(vp, &vattr, cred);
392 if (error)
393 goto out;
394 NFSLOCKNODE(np);
395 np->n_mtime = vattr.va_mtime;
396 NFSUNLOCKNODE(np);
397 } else {
398 NFSUNLOCKNODE(np);
399 error = VOP_GETATTR(vp, &vattr, cred);
400 if (error)
401 goto out;
402 NFSLOCKNODE(np);
403 if ((np->n_flag & NSIZECHANGED)
404 || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) {
405 NFSUNLOCKNODE(np);
406 if (vp->v_type == VDIR)
407 ncl_invaldir(vp);
408 error = ncl_vinvalbuf(vp, V_SAVE | V_ALLOWCLEAN, td, 1);
409 if (error != 0)
410 goto out;
411 NFSLOCKNODE(np);
412 np->n_mtime = vattr.va_mtime;
413 np->n_flag &= ~NSIZECHANGED;
414 }
415 NFSUNLOCKNODE(np);
416 }
417 out:
418 ncl_excl_finish(vp, old_lock);
419 return (error);
420 }
421
422 /*
423 * Vnode op for read using bio
424 */
425 int
426 ncl_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred)
427 {
428 struct nfsnode *np = VTONFS(vp);
429 struct buf *bp, *rabp;
430 struct thread *td;
431 struct nfsmount *nmp = VFSTONFS(vp->v_mount);
432 daddr_t lbn, rabn;
433 int biosize, bcount, error, i, n, nra, on, save2, seqcount;
434 off_t tmp_off;
435
436 KASSERT(uio->uio_rw == UIO_READ, ("ncl_read mode"));
437 if (uio->uio_resid == 0)
438 return (0);
439 if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */
440 return (EINVAL);
441 td = uio->uio_td;
442
443 mtx_lock(&nmp->nm_mtx);
444 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 &&
445 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) {
446 mtx_unlock(&nmp->nm_mtx);
447 (void)ncl_fsinfo(nmp, vp, cred, td);
448 mtx_lock(&nmp->nm_mtx);
449 }
450 if (nmp->nm_rsize == 0 || nmp->nm_readdirsize == 0)
451 (void) newnfs_iosize(nmp);
452
453 tmp_off = uio->uio_offset + uio->uio_resid;
454 if (vp->v_type != VDIR &&
455 (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset)) {
456 mtx_unlock(&nmp->nm_mtx);
457 return (EFBIG);
458 }
459 mtx_unlock(&nmp->nm_mtx);
460
461 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG))
462 /* No caching/ no readaheads. Just read data into the user buffer */
463 return ncl_readrpc(vp, uio, cred);
464
465 n = 0;
466 on = 0;
467 biosize = vp->v_bufobj.bo_bsize;
468 seqcount = (int)((off_t)(ioflag >> IO_SEQSHIFT) * biosize / BKVASIZE);
469
470 error = nfs_bioread_check_cons(vp, td, cred);
471 if (error)
472 return error;
473
474 save2 = curthread_pflags2_set(TDP2_SBPAGES);
475 do {
476 u_quad_t nsize;
477
478 NFSLOCKNODE(np);
479 nsize = np->n_size;
480 NFSUNLOCKNODE(np);
481
482 switch (vp->v_type) {
483 case VREG:
484 NFSINCRGLOBAL(nfsstatsv1.biocache_reads);
485 lbn = uio->uio_offset / biosize;
486 on = uio->uio_offset - (lbn * biosize);
487
488 /*
489 * Start the read ahead(s), as required.
490 */
491 if (nmp->nm_readahead > 0) {
492 for (nra = 0; nra < nmp->nm_readahead && nra < seqcount &&
493 (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) {
494 rabn = lbn + 1 + nra;
495 if (incore(&vp->v_bufobj, rabn) == NULL) {
496 rabp = nfs_getcacheblk(vp, rabn, biosize, td);
497 if (!rabp) {
498 error = newnfs_sigintr(nmp, td);
499 if (error == 0)
500 error = EINTR;
501 goto out;
502 }
503 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) {
504 rabp->b_flags |= B_ASYNC;
505 rabp->b_iocmd = BIO_READ;
506 vfs_busy_pages(rabp, 0);
507 if (ncl_asyncio(nmp, rabp, cred, td)) {
508 rabp->b_flags |= B_INVAL;
509 rabp->b_ioflags |= BIO_ERROR;
510 vfs_unbusy_pages(rabp);
511 brelse(rabp);
512 break;
513 }
514 } else {
515 brelse(rabp);
516 }
517 }
518 }
519 }
520
521 /* Note that bcount is *not* DEV_BSIZE aligned. */
522 bcount = biosize;
523 if ((off_t)lbn * biosize >= nsize) {
524 bcount = 0;
525 } else if ((off_t)(lbn + 1) * biosize > nsize) {
526 bcount = nsize - (off_t)lbn * biosize;
527 }
528 bp = nfs_getcacheblk(vp, lbn, bcount, td);
529
530 if (!bp) {
531 error = newnfs_sigintr(nmp, td);
532 if (error == 0)
533 error = EINTR;
534 goto out;
535 }
536
537 /*
538 * If B_CACHE is not set, we must issue the read. If this
539 * fails, we return an error.
540 */
541
542 if ((bp->b_flags & B_CACHE) == 0) {
543 bp->b_iocmd = BIO_READ;
544 vfs_busy_pages(bp, 0);
545 error = ncl_doio(vp, bp, cred, td, 0);
546 if (error) {
547 brelse(bp);
548 goto out;
549 }
550 }
551
552 /*
553 * on is the offset into the current bp. Figure out how many
554 * bytes we can copy out of the bp. Note that bcount is
555 * NOT DEV_BSIZE aligned.
556 *
557 * Then figure out how many bytes we can copy into the uio.
558 */
559
560 n = 0;
561 if (on < bcount)
562 n = MIN((unsigned)(bcount - on), uio->uio_resid);
563 break;
564 case VLNK:
565 NFSINCRGLOBAL(nfsstatsv1.biocache_readlinks);
566 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, td);
567 if (!bp) {
568 error = newnfs_sigintr(nmp, td);
569 if (error == 0)
570 error = EINTR;
571 goto out;
572 }
573 if ((bp->b_flags & B_CACHE) == 0) {
574 bp->b_iocmd = BIO_READ;
575 vfs_busy_pages(bp, 0);
576 error = ncl_doio(vp, bp, cred, td, 0);
577 if (error) {
578 bp->b_ioflags |= BIO_ERROR;
579 brelse(bp);
580 goto out;
581 }
582 }
583 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid);
584 on = 0;
585 break;
586 case VDIR:
587 NFSINCRGLOBAL(nfsstatsv1.biocache_readdirs);
588 NFSLOCKNODE(np);
589 if (np->n_direofoffset
590 && uio->uio_offset >= np->n_direofoffset) {
591 NFSUNLOCKNODE(np);
592 error = 0;
593 goto out;
594 }
595 NFSUNLOCKNODE(np);
596 lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ;
597 on = uio->uio_offset & (NFS_DIRBLKSIZ - 1);
598 bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, td);
599 if (!bp) {
600 error = newnfs_sigintr(nmp, td);
601 if (error == 0)
602 error = EINTR;
603 goto out;
604 }
605 if ((bp->b_flags & B_CACHE) == 0) {
606 bp->b_iocmd = BIO_READ;
607 vfs_busy_pages(bp, 0);
608 error = ncl_doio(vp, bp, cred, td, 0);
609 if (error) {
610 brelse(bp);
611 }
612 while (error == NFSERR_BAD_COOKIE) {
613 ncl_invaldir(vp);
614 error = ncl_vinvalbuf(vp, 0, td, 1);
615
616 /*
617 * Yuck! The directory has been modified on the
618 * server. The only way to get the block is by
619 * reading from the beginning to get all the
620 * offset cookies.
621 *
622 * Leave the last bp intact unless there is an error.
623 * Loop back up to the while if the error is another
624 * NFSERR_BAD_COOKIE (double yuch!).
625 */
626 for (i = 0; i <= lbn && !error; i++) {
627 NFSLOCKNODE(np);
628 if (np->n_direofoffset
629 && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) {
630 NFSUNLOCKNODE(np);
631 error = 0;
632 goto out;
633 }
634 NFSUNLOCKNODE(np);
635 bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, td);
636 if (!bp) {
637 error = newnfs_sigintr(nmp, td);
638 if (error == 0)
639 error = EINTR;
640 goto out;
641 }
642 if ((bp->b_flags & B_CACHE) == 0) {
643 bp->b_iocmd = BIO_READ;
644 vfs_busy_pages(bp, 0);
645 error = ncl_doio(vp, bp, cred, td, 0);
646 /*
647 * no error + B_INVAL == directory EOF,
648 * use the block.
649 */
650 if (error == 0 && (bp->b_flags & B_INVAL))
651 break;
652 }
653 /*
654 * An error will throw away the block and the
655 * for loop will break out. If no error and this
656 * is not the block we want, we throw away the
657 * block and go for the next one via the for loop.
658 */
659 if (error || i < lbn)
660 brelse(bp);
661 }
662 }
663 /*
664 * The above while is repeated if we hit another cookie
665 * error. If we hit an error and it wasn't a cookie error,
666 * we give up.
667 */
668 if (error)
669 goto out;
670 }
671
672 /*
673 * If not eof and read aheads are enabled, start one.
674 * (You need the current block first, so that you have the
675 * directory offset cookie of the next block.)
676 */
677 NFSLOCKNODE(np);
678 if (nmp->nm_readahead > 0 &&
679 (bp->b_flags & B_INVAL) == 0 &&
680 (np->n_direofoffset == 0 ||
681 (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) &&
682 incore(&vp->v_bufobj, lbn + 1) == NULL) {
683 NFSUNLOCKNODE(np);
684 rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td);
685 if (rabp) {
686 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) {
687 rabp->b_flags |= B_ASYNC;
688 rabp->b_iocmd = BIO_READ;
689 vfs_busy_pages(rabp, 0);
690 if (ncl_asyncio(nmp, rabp, cred, td)) {
691 rabp->b_flags |= B_INVAL;
692 rabp->b_ioflags |= BIO_ERROR;
693 vfs_unbusy_pages(rabp);
694 brelse(rabp);
695 }
696 } else {
697 brelse(rabp);
698 }
699 }
700 NFSLOCKNODE(np);
701 }
702 /*
703 * Unlike VREG files, whos buffer size ( bp->b_bcount ) is
704 * chopped for the EOF condition, we cannot tell how large
705 * NFS directories are going to be until we hit EOF. So
706 * an NFS directory buffer is *not* chopped to its EOF. Now,
707 * it just so happens that b_resid will effectively chop it
708 * to EOF. *BUT* this information is lost if the buffer goes
709 * away and is reconstituted into a B_CACHE state ( due to
710 * being VMIO ) later. So we keep track of the directory eof
711 * in np->n_direofoffset and chop it off as an extra step
712 * right here.
713 */
714 n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on);
715 if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset)
716 n = np->n_direofoffset - uio->uio_offset;
717 NFSUNLOCKNODE(np);
718 break;
719 default:
720 printf(" ncl_bioread: type %x unexpected\n", vp->v_type);
721 bp = NULL;
722 break;
723 }
724
725 if (n > 0) {
726 error = vn_io_fault_uiomove(bp->b_data + on, (int)n, uio);
727 }
728 if (vp->v_type == VLNK)
729 n = 0;
730 if (bp != NULL)
731 brelse(bp);
732 } while (error == 0 && uio->uio_resid > 0 && n > 0);
733 out:
734 curthread_pflags2_restore(save2);
735 if ((curthread->td_pflags2 & TDP2_SBPAGES) == 0) {
736 NFSLOCKNODE(np);
737 ncl_pager_setsize(vp, NULL);
738 }
739 return (error);
740 }
741
742 /*
743 * The NFS write path cannot handle iovecs with len > 1. So we need to
744 * break up iovecs accordingly (restricting them to wsize).
745 * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf).
746 * For the ASYNC case, 2 copies are needed. The first a copy from the
747 * user buffer to a staging buffer and then a second copy from the staging
748 * buffer to mbufs. This can be optimized by copying from the user buffer
749 * directly into mbufs and passing the chain down, but that requires a
750 * fair amount of re-working of the relevant codepaths (and can be done
751 * later).
752 */
753 static int
754 nfs_directio_write(struct vnode *vp, struct uio *uiop, struct ucred *cred,
755 int ioflag)
756 {
757 int error;
758 struct nfsmount *nmp = VFSTONFS(vp->v_mount);
759 struct thread *td = uiop->uio_td;
760 int size;
761 int wsize;
762
763 mtx_lock(&nmp->nm_mtx);
764 wsize = nmp->nm_wsize;
765 mtx_unlock(&nmp->nm_mtx);
766 if (ioflag & IO_SYNC) {
767 int iomode, must_commit;
768 struct uio uio;
769 struct iovec iov;
770 do_sync:
771 while (uiop->uio_resid > 0) {
772 size = MIN(uiop->uio_resid, wsize);
773 size = MIN(uiop->uio_iov->iov_len, size);
774 iov.iov_base = uiop->uio_iov->iov_base;
775 iov.iov_len = size;
776 uio.uio_iov = &iov;
777 uio.uio_iovcnt = 1;
778 uio.uio_offset = uiop->uio_offset;
779 uio.uio_resid = size;
780 uio.uio_segflg = uiop->uio_segflg;
781 uio.uio_rw = UIO_WRITE;
782 uio.uio_td = td;
783 iomode = NFSWRITE_FILESYNC;
784 /*
785 * When doing direct I/O we do not care if the
786 * server's write verifier has changed, but we
787 * do not want to update the verifier if it has
788 * changed, since that hides the change from
789 * writes being done through the buffer cache.
790 * By passing must_commit in set to two, the code
791 * in nfsrpc_writerpc() will not update the
792 * verifier on the mount point.
793 */
794 must_commit = 2;
795 error = ncl_writerpc(vp, &uio, cred, &iomode,
796 &must_commit, 0, ioflag);
797 KASSERT((must_commit == 2),
798 ("ncl_directio_write: Updated write verifier"));
799 if (error)
800 return (error);
801 if (iomode != NFSWRITE_FILESYNC)
802 printf("nfs_directio_write: Broken server "
803 "did not reply FILE_SYNC\n");
804 uiop->uio_offset += size;
805 uiop->uio_resid -= size;
806 if (uiop->uio_iov->iov_len <= size) {
807 uiop->uio_iovcnt--;
808 uiop->uio_iov++;
809 } else {
810 uiop->uio_iov->iov_base =
811 (char *)uiop->uio_iov->iov_base + size;
812 uiop->uio_iov->iov_len -= size;
813 }
814 }
815 } else {
816 struct uio *t_uio;
817 struct iovec *t_iov;
818 struct buf *bp;
819
820 /*
821 * Break up the write into blocksize chunks and hand these
822 * over to nfsiod's for write back.
823 * Unfortunately, this incurs a copy of the data. Since
824 * the user could modify the buffer before the write is
825 * initiated.
826 *
827 * The obvious optimization here is that one of the 2 copies
828 * in the async write path can be eliminated by copying the
829 * data here directly into mbufs and passing the mbuf chain
830 * down. But that will require a fair amount of re-working
831 * of the code and can be done if there's enough interest
832 * in NFS directio access.
833 */
834 while (uiop->uio_resid > 0) {
835 size = MIN(uiop->uio_resid, wsize);
836 size = MIN(uiop->uio_iov->iov_len, size);
837 bp = uma_zalloc(ncl_pbuf_zone, M_WAITOK);
838 t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK);
839 t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK);
840 t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK);
841 t_iov->iov_len = size;
842 t_uio->uio_iov = t_iov;
843 t_uio->uio_iovcnt = 1;
844 t_uio->uio_offset = uiop->uio_offset;
845 t_uio->uio_resid = size;
846 t_uio->uio_segflg = UIO_SYSSPACE;
847 t_uio->uio_rw = UIO_WRITE;
848 t_uio->uio_td = td;
849 KASSERT(uiop->uio_segflg == UIO_USERSPACE ||
850 uiop->uio_segflg == UIO_SYSSPACE,
851 ("nfs_directio_write: Bad uio_segflg"));
852 if (uiop->uio_segflg == UIO_USERSPACE) {
853 error = copyin(uiop->uio_iov->iov_base,
854 t_iov->iov_base, size);
855 if (error != 0)
856 goto err_free;
857 } else
858 /*
859 * UIO_SYSSPACE may never happen, but handle
860 * it just in case it does.
861 */
862 bcopy(uiop->uio_iov->iov_base, t_iov->iov_base,
863 size);
864 bp->b_flags |= B_DIRECT;
865 bp->b_iocmd = BIO_WRITE;
866 if (cred != NOCRED) {
867 crhold(cred);
868 bp->b_wcred = cred;
869 } else
870 bp->b_wcred = NOCRED;
871 bp->b_caller1 = (void *)t_uio;
872 bp->b_vp = vp;
873 error = ncl_asyncio(nmp, bp, NOCRED, td);
874 err_free:
875 if (error) {
876 free(t_iov->iov_base, M_NFSDIRECTIO);
877 free(t_iov, M_NFSDIRECTIO);
878 free(t_uio, M_NFSDIRECTIO);
879 bp->b_vp = NULL;
880 uma_zfree(ncl_pbuf_zone, bp);
881 if (error == EINTR)
882 return (error);
883 goto do_sync;
884 }
885 uiop->uio_offset += size;
886 uiop->uio_resid -= size;
887 if (uiop->uio_iov->iov_len <= size) {
888 uiop->uio_iovcnt--;
889 uiop->uio_iov++;
890 } else {
891 uiop->uio_iov->iov_base =
892 (char *)uiop->uio_iov->iov_base + size;
893 uiop->uio_iov->iov_len -= size;
894 }
895 }
896 }
897 return (0);
898 }
899
900 /*
901 * Vnode op for write using bio
902 */
903 int
904 ncl_write(struct vop_write_args *ap)
905 {
906 int biosize;
907 struct uio *uio = ap->a_uio;
908 struct thread *td = uio->uio_td;
909 struct vnode *vp = ap->a_vp;
910 struct nfsnode *np = VTONFS(vp);
911 struct ucred *cred = ap->a_cred;
912 int ioflag = ap->a_ioflag;
913 struct buf *bp;
914 struct vattr vattr;
915 struct nfsmount *nmp = VFSTONFS(vp->v_mount);
916 daddr_t lbn;
917 int bcount, noncontig_write, obcount;
918 int bp_cached, n, on, error = 0, error1, save2, wouldcommit;
919 size_t orig_resid, local_resid;
920 off_t orig_size, tmp_off;
921 struct timespec ts;
922
923 KASSERT(uio->uio_rw == UIO_WRITE, ("ncl_write mode"));
924 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread,
925 ("ncl_write proc"));
926 if (vp->v_type != VREG)
927 return (EIO);
928 NFSLOCKNODE(np);
929 if (np->n_flag & NWRITEERR) {
930 np->n_flag &= ~NWRITEERR;
931 NFSUNLOCKNODE(np);
932 return (np->n_error);
933 } else
934 NFSUNLOCKNODE(np);
935 mtx_lock(&nmp->nm_mtx);
936 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 &&
937 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) {
938 mtx_unlock(&nmp->nm_mtx);
939 (void)ncl_fsinfo(nmp, vp, cred, td);
940 mtx_lock(&nmp->nm_mtx);
941 }
942 if (nmp->nm_wsize == 0)
943 (void) newnfs_iosize(nmp);
944 mtx_unlock(&nmp->nm_mtx);
945
946 /*
947 * Synchronously flush pending buffers if we are in synchronous
948 * mode or if we are appending.
949 */
950 if ((ioflag & IO_APPEND) || ((ioflag & IO_SYNC) && (np->n_flag &
951 NMODIFIED))) {
952 /*
953 * For the case where IO_APPEND is being done using a
954 * direct output (to the NFS server) RPC and
955 * newnfs_directio_enable is 0, all buffer cache buffers,
956 * including ones not modified, must be invalidated.
957 * This ensures that stale data is not read out of the
958 * buffer cache. The call also invalidates all mapped
959 * pages and, since the exclusive lock is held on the vnode,
960 * new pages cannot be faulted in.
961 *
962 * For the case where newnfs_directio_enable is set
963 * (which is not the default), it is not obvious that
964 * stale data should be left in the buffer cache, but
965 * the code has been this way for over a decade without
966 * complaints. Note that, unlike doing IO_APPEND via
967 * a direct write RPC when newnfs_directio_enable is not set,
968 * when newnfs_directio_enable is set, reading is done via
969 * direct to NFS server RPCs as well.
970 */
971 np->n_attrstamp = 0;
972 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
973 error = ncl_vinvalbuf(vp, V_SAVE | ((ioflag &
974 IO_VMIO) != 0 ? V_VMIO : 0), td, 1);
975 if (error != 0)
976 return (error);
977 }
978
979 orig_resid = uio->uio_resid;
980 NFSLOCKNODE(np);
981 orig_size = np->n_size;
982 NFSUNLOCKNODE(np);
983
984 /*
985 * If IO_APPEND then load uio_offset. We restart here if we cannot
986 * get the append lock.
987 */
988 if (ioflag & IO_APPEND) {
989 /*
990 * For NFSv4, the AppendWrite will Verify the size against
991 * the file's size on the server. If not the same, the
992 * write will then be retried, using the file size returned
993 * by the AppendWrite. However, for NFSv2 and NFSv3, the
994 * size must be acquired here via a Getattr RPC.
995 * The AppendWrite is not done for a pNFS mount.
996 */
997 if (!NFSHASNFSV4(nmp) || NFSHASPNFS(nmp)) {
998 np->n_attrstamp = 0;
999 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
1000 error = VOP_GETATTR(vp, &vattr, cred);
1001 if (error)
1002 return (error);
1003 }
1004 NFSLOCKNODE(np);
1005 uio->uio_offset = np->n_size;
1006 NFSUNLOCKNODE(np);
1007 }
1008
1009 if (uio->uio_offset < 0)
1010 return (EINVAL);
1011 tmp_off = uio->uio_offset + uio->uio_resid;
1012 if (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset)
1013 return (EFBIG);
1014 if (uio->uio_resid == 0)
1015 return (0);
1016
1017 /*
1018 * Do IO_APPEND writing via a synchronous direct write.
1019 * This can result in a significant performance improvement.
1020 */
1021 if ((newnfs_directio_enable && (ioflag & IO_DIRECT)) ||
1022 (ioflag & IO_APPEND)) {
1023 /*
1024 * Direct writes to the server must be done NFSWRITE_FILESYNC,
1025 * because the write data is not cached and, therefore, the
1026 * write cannot be redone after a server reboot.
1027 * Set IO_SYNC to make this happen.
1028 */
1029 ioflag |= IO_SYNC;
1030 return (nfs_directio_write(vp, uio, cred, ioflag));
1031 }
1032
1033 /*
1034 * Maybe this should be above the vnode op call, but so long as
1035 * file servers have no limits, i don't think it matters
1036 */
1037 error = vn_rlimit_fsize(vp, uio, td);
1038 if (error != 0)
1039 return (error);
1040
1041 save2 = curthread_pflags2_set(TDP2_SBPAGES);
1042 biosize = vp->v_bufobj.bo_bsize;
1043 /*
1044 * Find all of this file's B_NEEDCOMMIT buffers. If our writes
1045 * would exceed the local maximum per-file write commit size when
1046 * combined with those, we must decide whether to flush,
1047 * go synchronous, or return error. We don't bother checking
1048 * IO_UNIT -- we just make all writes atomic anyway, as there's
1049 * no point optimizing for something that really won't ever happen.
1050 */
1051 wouldcommit = 0;
1052 if (!(ioflag & IO_SYNC)) {
1053 int nflag;
1054
1055 NFSLOCKNODE(np);
1056 nflag = np->n_flag;
1057 NFSUNLOCKNODE(np);
1058 if (nflag & NMODIFIED) {
1059 BO_LOCK(&vp->v_bufobj);
1060 if (vp->v_bufobj.bo_dirty.bv_cnt != 0) {
1061 TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd,
1062 b_bobufs) {
1063 if (bp->b_flags & B_NEEDCOMMIT)
1064 wouldcommit += bp->b_bcount;
1065 }
1066 }
1067 BO_UNLOCK(&vp->v_bufobj);
1068 }
1069 }
1070
1071 do {
1072 if (!(ioflag & IO_SYNC)) {
1073 wouldcommit += biosize;
1074 if (wouldcommit > nmp->nm_wcommitsize) {
1075 np->n_attrstamp = 0;
1076 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
1077 error = ncl_vinvalbuf(vp, V_SAVE | ((ioflag &
1078 IO_VMIO) != 0 ? V_VMIO : 0), td, 1);
1079 if (error != 0)
1080 goto out;
1081 wouldcommit = biosize;
1082 }
1083 }
1084
1085 NFSINCRGLOBAL(nfsstatsv1.biocache_writes);
1086 lbn = uio->uio_offset / biosize;
1087 on = uio->uio_offset - (lbn * biosize);
1088 n = MIN((unsigned)(biosize - on), uio->uio_resid);
1089 again:
1090 /*
1091 * Handle direct append and file extension cases, calculate
1092 * unaligned buffer size.
1093 */
1094 NFSLOCKNODE(np);
1095 if ((np->n_flag & NHASBEENLOCKED) == 0 &&
1096 (nmp->nm_flag & NFSMNT_NONCONTIGWR) != 0)
1097 noncontig_write = 1;
1098 else
1099 noncontig_write = 0;
1100 if ((uio->uio_offset == np->n_size ||
1101 (noncontig_write != 0 &&
1102 lbn == (np->n_size / biosize) &&
1103 uio->uio_offset + n > np->n_size)) && n) {
1104 NFSUNLOCKNODE(np);
1105 /*
1106 * Get the buffer (in its pre-append state to maintain
1107 * B_CACHE if it was previously set). Resize the
1108 * nfsnode after we have locked the buffer to prevent
1109 * readers from reading garbage.
1110 */
1111 obcount = np->n_size - (lbn * biosize);
1112 bp = nfs_getcacheblk(vp, lbn, obcount, td);
1113
1114 if (bp != NULL) {
1115 long save;
1116
1117 NFSLOCKNODE(np);
1118 np->n_size = uio->uio_offset + n;
1119 np->n_flag |= NMODIFIED;
1120 np->n_flag &= ~NVNSETSZSKIP;
1121 vnode_pager_setsize(vp, np->n_size);
1122 NFSUNLOCKNODE(np);
1123
1124 save = bp->b_flags & B_CACHE;
1125 bcount = on + n;
1126 allocbuf(bp, bcount);
1127 bp->b_flags |= save;
1128 if (noncontig_write != 0 && on > obcount)
1129 vfs_bio_bzero_buf(bp, obcount, on -
1130 obcount);
1131 }
1132 } else {
1133 /*
1134 * Obtain the locked cache block first, and then
1135 * adjust the file's size as appropriate.
1136 */
1137 bcount = on + n;
1138 if ((off_t)lbn * biosize + bcount < np->n_size) {
1139 if ((off_t)(lbn + 1) * biosize < np->n_size)
1140 bcount = biosize;
1141 else
1142 bcount = np->n_size - (off_t)lbn * biosize;
1143 }
1144 NFSUNLOCKNODE(np);
1145 bp = nfs_getcacheblk(vp, lbn, bcount, td);
1146 NFSLOCKNODE(np);
1147 if (uio->uio_offset + n > np->n_size) {
1148 np->n_size = uio->uio_offset + n;
1149 np->n_flag |= NMODIFIED;
1150 np->n_flag &= ~NVNSETSZSKIP;
1151 vnode_pager_setsize(vp, np->n_size);
1152 }
1153 NFSUNLOCKNODE(np);
1154 }
1155
1156 if (!bp) {
1157 error = newnfs_sigintr(nmp, td);
1158 if (!error)
1159 error = EINTR;
1160 break;
1161 }
1162
1163 /*
1164 * Issue a READ if B_CACHE is not set. In special-append
1165 * mode, B_CACHE is based on the buffer prior to the write
1166 * op and is typically set, avoiding the read. If a read
1167 * is required in special append mode, the server will
1168 * probably send us a short-read since we extended the file
1169 * on our end, resulting in b_resid == 0 and, thusly,
1170 * B_CACHE getting set.
1171 *
1172 * We can also avoid issuing the read if the write covers
1173 * the entire buffer. We have to make sure the buffer state
1174 * is reasonable in this case since we will not be initiating
1175 * I/O. See the comments in kern/vfs_bio.c's getblk() for
1176 * more information.
1177 *
1178 * B_CACHE may also be set due to the buffer being cached
1179 * normally.
1180 */
1181
1182 bp_cached = 1;
1183 if (on == 0 && n == bcount) {
1184 if ((bp->b_flags & B_CACHE) == 0)
1185 bp_cached = 0;
1186 bp->b_flags |= B_CACHE;
1187 bp->b_flags &= ~B_INVAL;
1188 bp->b_ioflags &= ~BIO_ERROR;
1189 }
1190
1191 if ((bp->b_flags & B_CACHE) == 0) {
1192 bp->b_iocmd = BIO_READ;
1193 vfs_busy_pages(bp, 0);
1194 error = ncl_doio(vp, bp, cred, td, 0);
1195 if (error) {
1196 brelse(bp);
1197 break;
1198 }
1199 }
1200 if (bp->b_wcred == NOCRED)
1201 bp->b_wcred = crhold(cred);
1202 NFSLOCKNODE(np);
1203 np->n_flag |= NMODIFIED;
1204 NFSUNLOCKNODE(np);
1205
1206 /*
1207 * If dirtyend exceeds file size, chop it down. This should
1208 * not normally occur but there is an append race where it
1209 * might occur XXX, so we log it.
1210 *
1211 * If the chopping creates a reverse-indexed or degenerate
1212 * situation with dirtyoff/end, we 0 both of them.
1213 */
1214
1215 if (bp->b_dirtyend > bcount) {
1216 printf("NFS append race @%lx:%d\n",
1217 (long)bp->b_blkno * DEV_BSIZE,
1218 bp->b_dirtyend - bcount);
1219 bp->b_dirtyend = bcount;
1220 }
1221
1222 if (bp->b_dirtyoff >= bp->b_dirtyend)
1223 bp->b_dirtyoff = bp->b_dirtyend = 0;
1224
1225 /*
1226 * If the new write will leave a contiguous dirty
1227 * area, just update the b_dirtyoff and b_dirtyend,
1228 * otherwise force a write rpc of the old dirty area.
1229 *
1230 * If there has been a file lock applied to this file
1231 * or vfs.nfs.old_noncontig_writing is set, do the following:
1232 * While it is possible to merge discontiguous writes due to
1233 * our having a B_CACHE buffer ( and thus valid read data
1234 * for the hole), we don't because it could lead to
1235 * significant cache coherency problems with multiple clients,
1236 * especially if locking is implemented later on.
1237 *
1238 * If vfs.nfs.old_noncontig_writing is not set and there has
1239 * not been file locking done on this file:
1240 * Relax coherency a bit for the sake of performance and
1241 * expand the current dirty region to contain the new
1242 * write even if it means we mark some non-dirty data as
1243 * dirty.
1244 */
1245
1246 if (noncontig_write == 0 && bp->b_dirtyend > 0 &&
1247 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) {
1248 if (bwrite(bp) == EINTR) {
1249 error = EINTR;
1250 break;
1251 }
1252 goto again;
1253 }
1254
1255 local_resid = uio->uio_resid;
1256 error = vn_io_fault_uiomove((char *)bp->b_data + on, n, uio);
1257
1258 if (error != 0 && !bp_cached) {
1259 /*
1260 * This block has no other content then what
1261 * possibly was written by the faulty uiomove.
1262 * Release it, forgetting the data pages, to
1263 * prevent the leak of uninitialized data to
1264 * usermode.
1265 */
1266 bp->b_ioflags |= BIO_ERROR;
1267 brelse(bp);
1268 uio->uio_offset -= local_resid - uio->uio_resid;
1269 uio->uio_resid = local_resid;
1270 break;
1271 }
1272
1273 /*
1274 * Since this block is being modified, it must be written
1275 * again and not just committed. Since write clustering does
1276 * not work for the stage 1 data write, only the stage 2
1277 * commit rpc, we have to clear B_CLUSTEROK as well.
1278 */
1279 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
1280
1281 /*
1282 * Get the partial update on the progress made from
1283 * uiomove, if an error occurred.
1284 */
1285 if (error != 0)
1286 n = local_resid - uio->uio_resid;
1287
1288 /*
1289 * Only update dirtyoff/dirtyend if not a degenerate
1290 * condition.
1291 */
1292 if (n > 0) {
1293 if (bp->b_dirtyend > 0) {
1294 bp->b_dirtyoff = min(on, bp->b_dirtyoff);
1295 bp->b_dirtyend = max((on + n), bp->b_dirtyend);
1296 } else {
1297 bp->b_dirtyoff = on;
1298 bp->b_dirtyend = on + n;
1299 }
1300 vfs_bio_set_valid(bp, on, n);
1301 }
1302
1303 /*
1304 * If IO_SYNC do bwrite().
1305 *
1306 * IO_INVAL appears to be unused. The idea appears to be
1307 * to turn off caching in this case. Very odd. XXX
1308 */
1309 if ((ioflag & IO_SYNC)) {
1310 if (ioflag & IO_INVAL)
1311 bp->b_flags |= B_NOCACHE;
1312 error1 = bwrite(bp);
1313 if (error1 != 0) {
1314 if (error == 0)
1315 error = error1;
1316 break;
1317 }
1318 } else if ((n + on) == biosize || (ioflag & IO_ASYNC) != 0) {
1319 bp->b_flags |= B_ASYNC;
1320 (void) ncl_writebp(bp, 0, NULL);
1321 } else {
1322 bdwrite(bp);
1323 }
1324
1325 if (error != 0)
1326 break;
1327 } while (uio->uio_resid > 0 && n > 0);
1328
1329 if (error == 0) {
1330 nanouptime(&ts);
1331 NFSLOCKNODE(np);
1332 np->n_localmodtime = ts;
1333 NFSUNLOCKNODE(np);
1334 } else {
1335 if (ioflag & IO_UNIT) {
1336 VATTR_NULL(&vattr);
1337 vattr.va_size = orig_size;
1338 /* IO_SYNC is handled implicitely */
1339 (void)VOP_SETATTR(vp, &vattr, cred);
1340 uio->uio_offset -= orig_resid - uio->uio_resid;
1341 uio->uio_resid = orig_resid;
1342 }
1343 }
1344
1345 out:
1346 curthread_pflags2_restore(save2);
1347 return (error);
1348 }
1349
1350 /*
1351 * Get an nfs cache block.
1352 *
1353 * Allocate a new one if the block isn't currently in the cache
1354 * and return the block marked busy. If the calling process is
1355 * interrupted by a signal for an interruptible mount point, return
1356 * NULL.
1357 *
1358 * The caller must carefully deal with the possible B_INVAL state of
1359 * the buffer. ncl_doio() clears B_INVAL (and ncl_asyncio() clears it
1360 * indirectly), so synchronous reads can be issued without worrying about
1361 * the B_INVAL state. We have to be a little more careful when dealing
1362 * with writes (see comments in nfs_write()) when extending a file past
1363 * its EOF.
1364 */
1365 static struct buf *
1366 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td)
1367 {
1368 struct buf *bp;
1369 struct mount *mp;
1370 struct nfsmount *nmp;
1371
1372 mp = vp->v_mount;
1373 nmp = VFSTONFS(mp);
1374
1375 if (nmp->nm_flag & NFSMNT_INT) {
1376 sigset_t oldset;
1377
1378 newnfs_set_sigmask(td, &oldset);
1379 bp = getblk(vp, bn, size, PCATCH, 0, 0);
1380 newnfs_restore_sigmask(td, &oldset);
1381 while (bp == NULL) {
1382 if (newnfs_sigintr(nmp, td))
1383 return (NULL);
1384 bp = getblk(vp, bn, size, 0, 2 * hz, 0);
1385 }
1386 } else {
1387 bp = getblk(vp, bn, size, 0, 0, 0);
1388 }
1389
1390 if (vp->v_type == VREG)
1391 bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / DEV_BSIZE);
1392 return (bp);
1393 }
1394
1395 /*
1396 * Flush and invalidate all dirty buffers. If another process is already
1397 * doing the flush, just wait for completion.
1398 */
1399 int
1400 ncl_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg)
1401 {
1402 struct nfsnode *np = VTONFS(vp);
1403 struct nfsmount *nmp = VFSTONFS(vp->v_mount);
1404 int error = 0, slpflag, slptimeo;
1405 bool old_lock;
1406 struct timespec ts;
1407
1408 ASSERT_VOP_LOCKED(vp, "ncl_vinvalbuf");
1409
1410 if ((nmp->nm_flag & NFSMNT_INT) == 0)
1411 intrflg = 0;
1412 if (NFSCL_FORCEDISM(nmp->nm_mountp))
1413 intrflg = 1;
1414 if (intrflg) {
1415 slpflag = PCATCH;
1416 slptimeo = 2 * hz;
1417 } else {
1418 slpflag = 0;
1419 slptimeo = 0;
1420 }
1421
1422 old_lock = ncl_excl_start(vp);
1423 if (old_lock)
1424 flags |= V_ALLOWCLEAN;
1425
1426 /*
1427 * Now, flush as required.
1428 */
1429 if ((flags & (V_SAVE | V_VMIO)) == V_SAVE &&
1430 vp->v_bufobj.bo_object != NULL) {
1431 VM_OBJECT_WLOCK(vp->v_bufobj.bo_object);
1432 vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC);
1433 VM_OBJECT_WUNLOCK(vp->v_bufobj.bo_object);
1434 /*
1435 * If the page clean was interrupted, fail the invalidation.
1436 * Not doing so, we run the risk of losing dirty pages in the
1437 * vinvalbuf() call below.
1438 */
1439 if (intrflg && (error = newnfs_sigintr(nmp, td)))
1440 goto out;
1441 }
1442
1443 error = vinvalbuf(vp, flags, slpflag, 0);
1444 while (error) {
1445 if (intrflg && (error = newnfs_sigintr(nmp, td)))
1446 goto out;
1447 error = vinvalbuf(vp, flags, 0, slptimeo);
1448 }
1449 if (NFSHASPNFS(nmp)) {
1450 nfscl_layoutcommit(vp, td);
1451 nanouptime(&ts);
1452 /*
1453 * Invalidate the attribute cache, since writes to a DS
1454 * won't update the size attribute.
1455 */
1456 NFSLOCKNODE(np);
1457 np->n_attrstamp = 0;
1458 } else {
1459 nanouptime(&ts);
1460 NFSLOCKNODE(np);
1461 }
1462 if (np->n_directio_asyncwr == 0 && (np->n_flag & NMODIFIED) != 0) {
1463 np->n_localmodtime = ts;
1464 np->n_flag &= ~NMODIFIED;
1465 }
1466 NFSUNLOCKNODE(np);
1467 out:
1468 ncl_excl_finish(vp, old_lock);
1469 return error;
1470 }
1471
1472 /*
1473 * Initiate asynchronous I/O. Return an error if no nfsiods are available.
1474 * This is mainly to avoid queueing async I/O requests when the nfsiods
1475 * are all hung on a dead server.
1476 *
1477 * Note: ncl_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp
1478 * is eventually dequeued by the async daemon, ncl_doio() *will*.
1479 */
1480 int
1481 ncl_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td)
1482 {
1483 int iod;
1484 int gotiod;
1485 int slpflag = 0;
1486 int slptimeo = 0;
1487 int error, error2;
1488
1489 /*
1490 * Commits are usually short and sweet so lets save some cpu and
1491 * leave the async daemons for more important rpc's (such as reads
1492 * and writes).
1493 *
1494 * Readdirplus RPCs do vget()s to acquire the vnodes for entries
1495 * in the directory in order to update attributes. This can deadlock
1496 * with another thread that is waiting for async I/O to be done by
1497 * an nfsiod thread while holding a lock on one of these vnodes.
1498 * To avoid this deadlock, don't allow the async nfsiod threads to
1499 * perform Readdirplus RPCs.
1500 */
1501 NFSLOCKIOD();
1502 if ((bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) &&
1503 (nmp->nm_bufqiods > ncl_numasync / 2)) ||
1504 (bp->b_vp->v_type == VDIR && (nmp->nm_flag & NFSMNT_RDIRPLUS))) {
1505 NFSUNLOCKIOD();
1506 return(EIO);
1507 }
1508 again:
1509 if (nmp->nm_flag & NFSMNT_INT)
1510 slpflag = PCATCH;
1511 gotiod = FALSE;
1512
1513 /*
1514 * Find a free iod to process this request.
1515 */
1516 for (iod = 0; iod < ncl_numasync; iod++)
1517 if (ncl_iodwant[iod] == NFSIOD_AVAILABLE) {
1518 gotiod = TRUE;
1519 break;
1520 }
1521
1522 /*
1523 * Try to create one if none are free.
1524 */
1525 if (!gotiod)
1526 ncl_nfsiodnew();
1527 else {
1528 /*
1529 * Found one, so wake it up and tell it which
1530 * mount to process.
1531 */
1532 NFS_DPF(ASYNCIO, ("ncl_asyncio: waking iod %d for mount %p\n",
1533 iod, nmp));
1534 ncl_iodwant[iod] = NFSIOD_NOT_AVAILABLE;
1535 ncl_iodmount[iod] = nmp;
1536 nmp->nm_bufqiods++;
1537 wakeup(&ncl_iodwant[iod]);
1538 }
1539
1540 /*
1541 * If none are free, we may already have an iod working on this mount
1542 * point. If so, it will process our request.
1543 */
1544 if (!gotiod) {
1545 if (nmp->nm_bufqiods > 0) {
1546 NFS_DPF(ASYNCIO,
1547 ("ncl_asyncio: %d iods are already processing mount %p\n",
1548 nmp->nm_bufqiods, nmp));
1549 gotiod = TRUE;
1550 }
1551 }
1552
1553 /*
1554 * If we have an iod which can process the request, then queue
1555 * the buffer.
1556 */
1557 if (gotiod) {
1558 /*
1559 * Ensure that the queue never grows too large. We still want
1560 * to asynchronize so we block rather then return EIO.
1561 */
1562 while (nmp->nm_bufqlen >= 2*ncl_numasync) {
1563 NFS_DPF(ASYNCIO,
1564 ("ncl_asyncio: waiting for mount %p queue to drain\n", nmp));
1565 nmp->nm_bufqwant = TRUE;
1566 error = newnfs_msleep(td, &nmp->nm_bufq,
1567 &ncl_iod_mutex, slpflag | PRIBIO, "nfsaio",
1568 slptimeo);
1569 if (error) {
1570 error2 = newnfs_sigintr(nmp, td);
1571 if (error2) {
1572 NFSUNLOCKIOD();
1573 return (error2);
1574 }
1575 if (slpflag == PCATCH) {
1576 slpflag = 0;
1577 slptimeo = 2 * hz;
1578 }
1579 }
1580 /*
1581 * We might have lost our iod while sleeping,
1582 * so check and loop if necessary.
1583 */
1584 goto again;
1585 }
1586
1587 /* We might have lost our nfsiod */
1588 if (nmp->nm_bufqiods == 0) {
1589 NFS_DPF(ASYNCIO,
1590 ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp));
1591 goto again;
1592 }
1593
1594 if (bp->b_iocmd == BIO_READ) {
1595 if (bp->b_rcred == NOCRED && cred != NOCRED)
1596 bp->b_rcred = crhold(cred);
1597 } else {
1598 if (bp->b_wcred == NOCRED && cred != NOCRED)
1599 bp->b_wcred = crhold(cred);
1600 }
1601
1602 if (bp->b_flags & B_REMFREE)
1603 bremfreef(bp);
1604 BUF_KERNPROC(bp);
1605 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist);
1606 nmp->nm_bufqlen++;
1607 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) {
1608 NFSLOCKNODE(VTONFS(bp->b_vp));
1609 VTONFS(bp->b_vp)->n_flag |= NMODIFIED;
1610 VTONFS(bp->b_vp)->n_directio_asyncwr++;
1611 NFSUNLOCKNODE(VTONFS(bp->b_vp));
1612 }
1613 NFSUNLOCKIOD();
1614 return (0);
1615 }
1616
1617 NFSUNLOCKIOD();
1618
1619 /*
1620 * All the iods are busy on other mounts, so return EIO to
1621 * force the caller to process the i/o synchronously.
1622 */
1623 NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods available, i/o is synchronous\n"));
1624 return (EIO);
1625 }
1626
1627 void
1628 ncl_doio_directwrite(struct buf *bp)
1629 {
1630 int iomode, must_commit;
1631 struct uio *uiop = (struct uio *)bp->b_caller1;
1632 char *iov_base = uiop->uio_iov->iov_base;
1633
1634 iomode = NFSWRITE_FILESYNC;
1635 uiop->uio_td = NULL; /* NULL since we're in nfsiod */
1636 /*
1637 * When doing direct I/O we do not care if the
1638 * server's write verifier has changed, but we
1639 * do not want to update the verifier if it has
1640 * changed, since that hides the change from
1641 * writes being done through the buffer cache.
1642 * By passing must_commit in set to two, the code
1643 * in nfsrpc_writerpc() will not update the
1644 * verifier on the mount point.
1645 */
1646 must_commit = 2;
1647 ncl_writerpc(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit, 0, 0);
1648 KASSERT((must_commit == 2), ("ncl_doio_directwrite: Updated write"
1649 " verifier"));
1650 if (iomode != NFSWRITE_FILESYNC)
1651 printf("ncl_doio_directwrite: Broken server "
1652 "did not reply FILE_SYNC\n");
1653 free(iov_base, M_NFSDIRECTIO);
1654 free(uiop->uio_iov, M_NFSDIRECTIO);
1655 free(uiop, M_NFSDIRECTIO);
1656 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) {
1657 struct nfsnode *np = VTONFS(bp->b_vp);
1658 NFSLOCKNODE(np);
1659 if (NFSHASPNFS(VFSTONFS(bp->b_vp->v_mount))) {
1660 /*
1661 * Invalidate the attribute cache, since writes to a DS
1662 * won't update the size attribute.
1663 */
1664 np->n_attrstamp = 0;
1665 }
1666 np->n_directio_asyncwr--;
1667 if (np->n_directio_asyncwr == 0) {
1668 np->n_flag &= ~NMODIFIED;
1669 if ((np->n_flag & NFSYNCWAIT)) {
1670 np->n_flag &= ~NFSYNCWAIT;
1671 wakeup((caddr_t)&np->n_directio_asyncwr);
1672 }
1673 }
1674 NFSUNLOCKNODE(np);
1675 }
1676 bp->b_vp = NULL;
1677 uma_zfree(ncl_pbuf_zone, bp);
1678 }
1679
1680 /*
1681 * Do an I/O operation to/from a cache block. This may be called
1682 * synchronously or from an nfsiod.
1683 */
1684 int
1685 ncl_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td,
1686 int called_from_strategy)
1687 {
1688 struct uio *uiop;
1689 struct nfsnode *np;
1690 struct nfsmount *nmp;
1691 int error = 0, iomode, must_commit = 0;
1692 struct uio uio;
1693 struct iovec io;
1694 struct proc *p = td ? td->td_proc : NULL;
1695 uint8_t iocmd;
1696
1697 np = VTONFS(vp);
1698 nmp = VFSTONFS(vp->v_mount);
1699 uiop = &uio;
1700 uiop->uio_iov = &io;
1701 uiop->uio_iovcnt = 1;
1702 uiop->uio_segflg = UIO_SYSSPACE;
1703 uiop->uio_td = td;
1704
1705 /*
1706 * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We
1707 * do this here so we do not have to do it in all the code that
1708 * calls us.
1709 */
1710 bp->b_flags &= ~B_INVAL;
1711 bp->b_ioflags &= ~BIO_ERROR;
1712
1713 KASSERT(!(bp->b_flags & B_DONE), ("ncl_doio: bp %p already marked done", bp));
1714 iocmd = bp->b_iocmd;
1715 if (iocmd == BIO_READ) {
1716 io.iov_len = uiop->uio_resid = bp->b_bcount;
1717 io.iov_base = bp->b_data;
1718 uiop->uio_rw = UIO_READ;
1719
1720 switch (vp->v_type) {
1721 case VREG:
1722 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE;
1723 NFSINCRGLOBAL(nfsstatsv1.read_bios);
1724 error = ncl_readrpc(vp, uiop, cr);
1725
1726 if (!error) {
1727 if (uiop->uio_resid) {
1728 /*
1729 * If we had a short read with no error, we must have
1730 * hit a file hole. We should zero-fill the remainder.
1731 * This can also occur if the server hits the file EOF.
1732 *
1733 * Holes used to be able to occur due to pending
1734 * writes, but that is not possible any longer.
1735 */
1736 int nread = bp->b_bcount - uiop->uio_resid;
1737 ssize_t left = uiop->uio_resid;
1738
1739 if (left > 0)
1740 bzero((char *)bp->b_data + nread, left);
1741 uiop->uio_resid = 0;
1742 }
1743 }
1744 /* ASSERT_VOP_LOCKED(vp, "ncl_doio"); */
1745 if (p && vp->v_writecount <= -1) {
1746 NFSLOCKNODE(np);
1747 if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.na_mtime)) {
1748 NFSUNLOCKNODE(np);
1749 PROC_LOCK(p);
1750 killproc(p, "text file modification");
1751 PROC_UNLOCK(p);
1752 } else
1753 NFSUNLOCKNODE(np);
1754 }
1755 break;
1756 case VLNK:
1757 uiop->uio_offset = (off_t)0;
1758 NFSINCRGLOBAL(nfsstatsv1.readlink_bios);
1759 error = ncl_readlinkrpc(vp, uiop, cr);
1760 break;
1761 case VDIR:
1762 NFSINCRGLOBAL(nfsstatsv1.readdir_bios);
1763 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ;
1764 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) {
1765 error = ncl_readdirplusrpc(vp, uiop, cr, td);
1766 if (error == NFSERR_NOTSUPP)
1767 nmp->nm_flag &= ~NFSMNT_RDIRPLUS;
1768 }
1769 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0)
1770 error = ncl_readdirrpc(vp, uiop, cr, td);
1771 /*
1772 * end-of-directory sets B_INVAL but does not generate an
1773 * error.
1774 */
1775 if (error == 0 && uiop->uio_resid == bp->b_bcount)
1776 bp->b_flags |= B_INVAL;
1777 break;
1778 default:
1779 printf("ncl_doio: type %x unexpected\n", vp->v_type);
1780 break;
1781 }
1782 if (error) {
1783 bp->b_ioflags |= BIO_ERROR;
1784 bp->b_error = error;
1785 }
1786 } else {
1787 /*
1788 * If we only need to commit, try to commit
1789 */
1790 if (bp->b_flags & B_NEEDCOMMIT) {
1791 int retv;
1792 off_t off;
1793
1794 off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff;
1795 retv = ncl_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff,
1796 bp->b_wcred, td);
1797 if (NFSCL_FORCEDISM(vp->v_mount) || retv == 0) {
1798 bp->b_dirtyoff = bp->b_dirtyend = 0;
1799 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
1800 bp->b_resid = 0;
1801 bufdone(bp);
1802 return (0);
1803 }
1804 if (retv == NFSERR_STALEWRITEVERF) {
1805 ncl_clearcommit(vp->v_mount);
1806 }
1807 }
1808
1809 /*
1810 * Setup for actual write
1811 */
1812 NFSLOCKNODE(np);
1813 if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size)
1814 bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE;
1815 NFSUNLOCKNODE(np);
1816
1817 if (bp->b_dirtyend > bp->b_dirtyoff) {
1818 io.iov_len = uiop->uio_resid = bp->b_dirtyend
1819 - bp->b_dirtyoff;
1820 uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE
1821 + bp->b_dirtyoff;
1822 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff;
1823 uiop->uio_rw = UIO_WRITE;
1824 NFSINCRGLOBAL(nfsstatsv1.write_bios);
1825
1826 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC)
1827 iomode = NFSWRITE_UNSTABLE;
1828 else
1829 iomode = NFSWRITE_FILESYNC;
1830
1831 error = ncl_writerpc(vp, uiop, cr, &iomode, &must_commit,
1832 called_from_strategy, 0);
1833
1834 /*
1835 * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try
1836 * to cluster the buffers needing commit. This will allow
1837 * the system to submit a single commit rpc for the whole
1838 * cluster. We can do this even if the buffer is not 100%
1839 * dirty (relative to the NFS blocksize), so we optimize the
1840 * append-to-file-case.
1841 *
1842 * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be
1843 * cleared because write clustering only works for commit
1844 * rpc's, not for the data portion of the write).
1845 */
1846
1847 if (!error && iomode == NFSWRITE_UNSTABLE) {
1848 bp->b_flags |= B_NEEDCOMMIT;
1849 if (bp->b_dirtyoff == 0
1850 && bp->b_dirtyend == bp->b_bcount)
1851 bp->b_flags |= B_CLUSTEROK;
1852 } else {
1853 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
1854 }
1855
1856 /*
1857 * For an interrupted write, the buffer is still valid
1858 * and the write hasn't been pushed to the server yet,
1859 * so we can't set BIO_ERROR and report the interruption
1860 * by setting B_EINTR. For the B_ASYNC case, B_EINTR
1861 * is not relevant, so the rpc attempt is essentially
1862 * a noop. For the case of a V3 write rpc not being
1863 * committed to stable storage, the block is still
1864 * dirty and requires either a commit rpc or another
1865 * write rpc with iomode == NFSV3WRITE_FILESYNC before
1866 * the block is reused. This is indicated by setting
1867 * the B_DELWRI and B_NEEDCOMMIT flags.
1868 *
1869 * EIO is returned by ncl_writerpc() to indicate a recoverable
1870 * write error and is handled as above, except that
1871 * B_EINTR isn't set. One cause of this is a stale stateid
1872 * error for the RPC that indicates recovery is required,
1873 * when called with called_from_strategy != 0.
1874 *
1875 * If the buffer is marked B_PAGING, it does not reside on
1876 * the vp's paging queues so we cannot call bdirty(). The
1877 * bp in this case is not an NFS cache block so we should
1878 * be safe. XXX
1879 *
1880 * The logic below breaks up errors into recoverable and
1881 * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE
1882 * and keep the buffer around for potential write retries.
1883 * For the latter (eg ESTALE), we toss the buffer away (B_INVAL)
1884 * and save the error in the nfsnode. This is less than ideal
1885 * but necessary. Keeping such buffers around could potentially
1886 * cause buffer exhaustion eventually (they can never be written
1887 * out, so will get constantly be re-dirtied). It also causes
1888 * all sorts of vfs panics. For non-recoverable write errors,
1889 * also invalidate the attrcache, so we'll be forced to go over
1890 * the wire for this object, returning an error to user on next
1891 * call (most of the time).
1892 */
1893 if (error == EINTR || error == EIO || error == ETIMEDOUT
1894 || (!error && (bp->b_flags & B_NEEDCOMMIT))) {
1895 bp->b_flags &= ~(B_INVAL|B_NOCACHE);
1896 if ((bp->b_flags & B_PAGING) == 0) {
1897 bdirty(bp);
1898 bp->b_flags &= ~B_DONE;
1899 }
1900 if ((error == EINTR || error == ETIMEDOUT) &&
1901 (bp->b_flags & B_ASYNC) == 0)
1902 bp->b_flags |= B_EINTR;
1903 } else {
1904 if (error) {
1905 bp->b_ioflags |= BIO_ERROR;
1906 bp->b_flags |= B_INVAL;
1907 bp->b_error = np->n_error = error;
1908 NFSLOCKNODE(np);
1909 np->n_flag |= NWRITEERR;
1910 np->n_attrstamp = 0;
1911 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
1912 NFSUNLOCKNODE(np);
1913 }
1914 bp->b_dirtyoff = bp->b_dirtyend = 0;
1915 }
1916 } else {
1917 bp->b_resid = 0;
1918 bufdone(bp);
1919 return (0);
1920 }
1921 }
1922 bp->b_resid = uiop->uio_resid;
1923 if (must_commit == 1)
1924 ncl_clearcommit(vp->v_mount);
1925 bufdone(bp);
1926 return (error);
1927 }
1928
1929 /*
1930 * Used to aid in handling ftruncate() operations on the NFS client side.
1931 * Truncation creates a number of special problems for NFS. We have to
1932 * throw away VM pages and buffer cache buffers that are beyond EOF, and
1933 * we have to properly handle VM pages or (potentially dirty) buffers
1934 * that straddle the truncation point.
1935 */
1936
1937 int
1938 ncl_meta_setsize(struct vnode *vp, struct thread *td, u_quad_t nsize)
1939 {
1940 struct nfsnode *np = VTONFS(vp);
1941 u_quad_t tsize;
1942 int biosize = vp->v_bufobj.bo_bsize;
1943 int error = 0;
1944
1945 NFSLOCKNODE(np);
1946 tsize = np->n_size;
1947 np->n_size = nsize;
1948 NFSUNLOCKNODE(np);
1949
1950 if (nsize < tsize) {
1951 struct buf *bp;
1952 daddr_t lbn;
1953 int bufsize;
1954
1955 /*
1956 * vtruncbuf() doesn't get the buffer overlapping the
1957 * truncation point. We may have a B_DELWRI and/or B_CACHE
1958 * buffer that now needs to be truncated.
1959 */
1960 error = vtruncbuf(vp, nsize, biosize);
1961 lbn = nsize / biosize;
1962 bufsize = nsize - (lbn * biosize);
1963 bp = nfs_getcacheblk(vp, lbn, bufsize, td);
1964 if (!bp)
1965 return EINTR;
1966 if (bp->b_dirtyoff > bp->b_bcount)
1967 bp->b_dirtyoff = bp->b_bcount;
1968 if (bp->b_dirtyend > bp->b_bcount)
1969 bp->b_dirtyend = bp->b_bcount;
1970 bp->b_flags |= B_RELBUF; /* don't leave garbage around */
1971 brelse(bp);
1972 } else {
1973 vnode_pager_setsize(vp, nsize);
1974 }
1975 return(error);
1976 }
Cache object: 741264fc890f6ebb9caaa4b20c4cc42d
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