nfs_bio.c revision 1.83 1 /* $NetBSD: nfs_bio.c,v 1.83 2002/10/21 12:52:32 yamt Exp $ */
2
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. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95
39 */
40
41 #include <sys/cdefs.h>
42 __KERNEL_RCSID(0, "$NetBSD: nfs_bio.c,v 1.83 2002/10/21 12:52:32 yamt Exp $");
43
44 #include "opt_nfs.h"
45 #include "opt_ddb.h"
46
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/resourcevar.h>
50 #include <sys/signalvar.h>
51 #include <sys/proc.h>
52 #include <sys/buf.h>
53 #include <sys/vnode.h>
54 #include <sys/mount.h>
55 #include <sys/kernel.h>
56 #include <sys/namei.h>
57 #include <sys/dirent.h>
58 #include <sys/malloc.h>
59
60 #include <uvm/uvm_extern.h>
61 #include <uvm/uvm.h>
62
63 #include <nfs/rpcv2.h>
64 #include <nfs/nfsproto.h>
65 #include <nfs/nfs.h>
66 #include <nfs/nfsmount.h>
67 #include <nfs/nqnfs.h>
68 #include <nfs/nfsnode.h>
69 #include <nfs/nfs_var.h>
70
71 extern int nfs_numasync;
72 extern int nfs_commitsize;
73 extern struct nfsstats nfsstats;
74
75 /*
76 * Vnode op for read using bio
77 * Any similarity to readip() is purely coincidental
78 */
79 int
80 nfs_bioread(vp, uio, ioflag, cred, cflag)
81 struct vnode *vp;
82 struct uio *uio;
83 int ioflag, cflag;
84 struct ucred *cred;
85 {
86 struct nfsnode *np = VTONFS(vp);
87 struct buf *bp = NULL, *rabp;
88 struct vattr vattr;
89 struct proc *p;
90 struct nfsmount *nmp = VFSTONFS(vp->v_mount);
91 struct nfsdircache *ndp = NULL, *nndp = NULL;
92 caddr_t baddr, ep, edp;
93 int got_buf = 0, error = 0, n = 0, on = 0, en, enn;
94 int enough = 0;
95 struct dirent *dp, *pdp;
96 off_t curoff = 0;
97
98 #ifdef DIAGNOSTIC
99 if (uio->uio_rw != UIO_READ)
100 panic("nfs_read mode");
101 #endif
102 if (uio->uio_resid == 0)
103 return (0);
104 if (vp->v_type != VDIR && uio->uio_offset < 0)
105 return (EINVAL);
106 p = uio->uio_procp;
107 #ifndef NFS_V2_ONLY
108 if ((nmp->nm_flag & NFSMNT_NFSV3) &&
109 !(nmp->nm_iflag & NFSMNT_GOTFSINFO))
110 (void)nfs_fsinfo(nmp, vp, cred, p);
111 #endif
112 if (vp->v_type != VDIR &&
113 (uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize)
114 return (EFBIG);
115
116 /*
117 * For nfs, cache consistency can only be maintained approximately.
118 * Although RFC1094 does not specify the criteria, the following is
119 * believed to be compatible with the reference port.
120 * For nqnfs, full cache consistency is maintained within the loop.
121 * For nfs:
122 * If the file's modify time on the server has changed since the
123 * last read rpc or you have written to the file,
124 * you may have lost data cache consistency with the
125 * server, so flush all of the file's data out of the cache.
126 * Then force a getattr rpc to ensure that you have up to date
127 * attributes.
128 * NB: This implies that cache data can be read when up to
129 * NFS_ATTRTIMEO seconds out of date. If you find that you need current
130 * attributes this could be forced by setting n_attrstamp to 0 before
131 * the VOP_GETATTR() call.
132 */
133
134 if ((nmp->nm_flag & NFSMNT_NQNFS) == 0 && vp->v_type != VLNK) {
135 if (np->n_flag & NMODIFIED) {
136 if (vp->v_type != VREG) {
137 if (vp->v_type != VDIR)
138 panic("nfs: bioread, not dir");
139 nfs_invaldircache(vp, 0);
140 np->n_direofoffset = 0;
141 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
142 if (error)
143 return (error);
144 }
145 np->n_attrstamp = 0;
146 error = VOP_GETATTR(vp, &vattr, cred, p);
147 if (error)
148 return (error);
149 np->n_mtime = vattr.va_mtime.tv_sec;
150 } else {
151 error = VOP_GETATTR(vp, &vattr, cred, p);
152 if (error)
153 return (error);
154 if (np->n_mtime != vattr.va_mtime.tv_sec) {
155 if (vp->v_type == VDIR) {
156 nfs_invaldircache(vp, 0);
157 np->n_direofoffset = 0;
158 }
159 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
160 if (error)
161 return (error);
162 np->n_mtime = vattr.va_mtime.tv_sec;
163 }
164 }
165 }
166
167 /*
168 * update the cached read creds for this node.
169 */
170
171 if (np->n_rcred) {
172 crfree(np->n_rcred);
173 }
174 np->n_rcred = cred;
175 crhold(cred);
176
177 do {
178 #ifndef NFS_V2_ONLY
179 /*
180 * Get a valid lease. If cached data is stale, flush it.
181 */
182 if (nmp->nm_flag & NFSMNT_NQNFS) {
183 if (NQNFS_CKINVALID(vp, np, ND_READ)) {
184 do {
185 error = nqnfs_getlease(vp, ND_READ, cred, p);
186 } while (error == NQNFS_EXPIRED);
187 if (error)
188 return (error);
189 if (np->n_lrev != np->n_brev ||
190 (np->n_flag & NQNFSNONCACHE) ||
191 ((np->n_flag & NMODIFIED) && vp->v_type == VDIR)) {
192 if (vp->v_type == VDIR) {
193 nfs_invaldircache(vp, 0);
194 np->n_direofoffset = 0;
195 }
196 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
197 if (error)
198 return (error);
199 np->n_brev = np->n_lrev;
200 }
201 } else if (vp->v_type == VDIR && (np->n_flag & NMODIFIED)) {
202 nfs_invaldircache(vp, 0);
203 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
204 np->n_direofoffset = 0;
205 if (error)
206 return (error);
207 }
208 }
209 #endif
210 /*
211 * Don't cache symlinks.
212 */
213 if (np->n_flag & NQNFSNONCACHE
214 || ((vp->v_flag & VROOT) && vp->v_type == VLNK)) {
215 switch (vp->v_type) {
216 case VREG:
217 return (nfs_readrpc(vp, uio));
218 case VLNK:
219 return (nfs_readlinkrpc(vp, uio, cred));
220 case VDIR:
221 break;
222 default:
223 printf(" NQNFSNONCACHE: type %x unexpected\n",
224 vp->v_type);
225 };
226 }
227 baddr = (caddr_t)0;
228 switch (vp->v_type) {
229 case VREG:
230 nfsstats.biocache_reads++;
231
232 error = 0;
233 if (uio->uio_offset >= np->n_size) {
234 break;
235 }
236 while (uio->uio_resid > 0) {
237 void *win;
238 vsize_t bytelen = MIN(np->n_size - uio->uio_offset,
239 uio->uio_resid);
240
241 if (bytelen == 0)
242 break;
243 win = ubc_alloc(&vp->v_uobj, uio->uio_offset,
244 &bytelen, UBC_READ);
245 error = uiomove(win, bytelen, uio);
246 ubc_release(win, 0);
247 if (error) {
248 break;
249 }
250 }
251 n = 0;
252 break;
253
254 case VLNK:
255 nfsstats.biocache_readlinks++;
256 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, p);
257 if (!bp)
258 return (EINTR);
259 if ((bp->b_flags & B_DONE) == 0) {
260 bp->b_flags |= B_READ;
261 error = nfs_doio(bp, p);
262 if (error) {
263 brelse(bp);
264 return (error);
265 }
266 }
267 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid);
268 got_buf = 1;
269 on = 0;
270 break;
271 case VDIR:
272 diragain:
273 nfsstats.biocache_readdirs++;
274 ndp = nfs_searchdircache(vp, uio->uio_offset,
275 (nmp->nm_flag & NFSMNT_XLATECOOKIE), 0);
276 if (!ndp) {
277 /*
278 * We've been handed a cookie that is not
279 * in the cache. If we're not translating
280 * 32 <-> 64, it may be a value that was
281 * flushed out of the cache because it grew
282 * too big. Let the server judge if it's
283 * valid or not. In the translation case,
284 * we have no way of validating this value,
285 * so punt.
286 */
287 if (nmp->nm_flag & NFSMNT_XLATECOOKIE)
288 return (EINVAL);
289 ndp = nfs_enterdircache(vp, uio->uio_offset,
290 uio->uio_offset, 0, 0);
291 }
292
293 if (uio->uio_offset != 0 &&
294 ndp->dc_cookie == np->n_direofoffset) {
295 nfsstats.direofcache_hits++;
296 return (0);
297 }
298
299 bp = nfs_getcacheblk(vp, ndp->dc_blkno, NFS_DIRBLKSIZ, p);
300 if (!bp)
301 return (EINTR);
302 if ((bp->b_flags & B_DONE) == 0) {
303 bp->b_flags |= B_READ;
304 bp->b_dcookie = ndp->dc_blkcookie;
305 error = nfs_doio(bp, p);
306 if (error) {
307 /*
308 * Yuck! The directory has been modified on the
309 * server. Punt and let the userland code
310 * deal with it.
311 */
312 brelse(bp);
313 if (error == NFSERR_BAD_COOKIE) {
314 nfs_invaldircache(vp, 0);
315 nfs_vinvalbuf(vp, 0, cred, p, 1);
316 error = EINVAL;
317 }
318 return (error);
319 }
320 }
321
322 /*
323 * Just return if we hit EOF right away with this
324 * block. Always check here, because direofoffset
325 * may have been set by an nfsiod since the last
326 * check.
327 */
328 if (np->n_direofoffset != 0 &&
329 ndp->dc_blkcookie == np->n_direofoffset) {
330 brelse(bp);
331 return (0);
332 }
333
334 /*
335 * Find the entry we were looking for in the block.
336 */
337
338 en = ndp->dc_entry;
339
340 pdp = dp = (struct dirent *)bp->b_data;
341 edp = bp->b_data + bp->b_bcount - bp->b_resid;
342 enn = 0;
343 while (enn < en && (caddr_t)dp < edp) {
344 pdp = dp;
345 dp = (struct dirent *)((caddr_t)dp + dp->d_reclen);
346 enn++;
347 }
348
349 /*
350 * If the entry number was bigger than the number of
351 * entries in the block, or the cookie of the previous
352 * entry doesn't match, the directory cache is
353 * stale. Flush it and try again (i.e. go to
354 * the server).
355 */
356 if ((caddr_t)dp >= edp || (caddr_t)dp + dp->d_reclen > edp ||
357 (en > 0 && NFS_GETCOOKIE(pdp) != ndp->dc_cookie)) {
358 #ifdef DEBUG
359 printf("invalid cache: %p %p %p off %lx %lx\n",
360 pdp, dp, edp,
361 (unsigned long)uio->uio_offset,
362 (unsigned long)NFS_GETCOOKIE(pdp));
363 #endif
364 brelse(bp);
365 nfs_invaldircache(vp, 0);
366 nfs_vinvalbuf(vp, 0, cred, p, 0);
367 goto diragain;
368 }
369
370 on = (caddr_t)dp - bp->b_data;
371
372 /*
373 * Cache all entries that may be exported to the
374 * user, as they may be thrown back at us. The
375 * NFSBIO_CACHECOOKIES flag indicates that all
376 * entries are being 'exported', so cache them all.
377 */
378
379 if (en == 0 && pdp == dp) {
380 dp = (struct dirent *)
381 ((caddr_t)dp + dp->d_reclen);
382 enn++;
383 }
384
385 if (uio->uio_resid < (bp->b_bcount - bp->b_resid - on)) {
386 n = uio->uio_resid;
387 enough = 1;
388 } else
389 n = bp->b_bcount - bp->b_resid - on;
390
391 ep = bp->b_data + on + n;
392
393 /*
394 * Find last complete entry to copy, caching entries
395 * (if requested) as we go.
396 */
397
398 while ((caddr_t)dp < ep && (caddr_t)dp + dp->d_reclen <= ep) {
399 if (cflag & NFSBIO_CACHECOOKIES) {
400 nndp = nfs_enterdircache(vp, NFS_GETCOOKIE(pdp),
401 ndp->dc_blkcookie, enn, bp->b_lblkno);
402 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) {
403 NFS_STASHCOOKIE32(pdp,
404 nndp->dc_cookie32);
405 }
406 }
407 pdp = dp;
408 dp = (struct dirent *)((caddr_t)dp + dp->d_reclen);
409 enn++;
410 }
411
412 /*
413 * If the last requested entry was not the last in the
414 * buffer (happens if NFS_DIRFRAGSIZ < NFS_DIRBLKSIZ),
415 * cache the cookie of the last requested one, and
416 * set of the offset to it.
417 */
418
419 if ((on + n) < bp->b_bcount - bp->b_resid) {
420 curoff = NFS_GETCOOKIE(pdp);
421 nndp = nfs_enterdircache(vp, curoff, ndp->dc_blkcookie,
422 enn, bp->b_lblkno);
423 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) {
424 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32);
425 curoff = nndp->dc_cookie32;
426 }
427 } else
428 curoff = bp->b_dcookie;
429
430 /*
431 * Always cache the entry for the next block,
432 * so that readaheads can use it.
433 */
434 nndp = nfs_enterdircache(vp, bp->b_dcookie, bp->b_dcookie, 0,0);
435 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) {
436 if (curoff == bp->b_dcookie) {
437 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32);
438 curoff = nndp->dc_cookie32;
439 }
440 }
441
442 n = ((caddr_t)pdp + pdp->d_reclen) - (bp->b_data + on);
443
444 /*
445 * If not eof and read aheads are enabled, start one.
446 * (You need the current block first, so that you have the
447 * directory offset cookie of the next block.)
448 */
449 if (nfs_numasync > 0 && nmp->nm_readahead > 0 &&
450 np->n_direofoffset == 0 && !(np->n_flag & NQNFSNONCACHE)) {
451 rabp = nfs_getcacheblk(vp, nndp->dc_blkno,
452 NFS_DIRBLKSIZ, p);
453 if (rabp) {
454 if ((rabp->b_flags & (B_DONE | B_DELWRI)) == 0) {
455 rabp->b_dcookie = nndp->dc_cookie;
456 rabp->b_flags |= (B_READ | B_ASYNC);
457 if (nfs_asyncio(rabp)) {
458 rabp->b_flags |= B_INVAL;
459 brelse(rabp);
460 }
461 } else
462 brelse(rabp);
463 }
464 }
465 got_buf = 1;
466 break;
467 default:
468 printf(" nfsbioread: type %x unexpected\n",vp->v_type);
469 break;
470 }
471
472 if (n > 0) {
473 if (!baddr)
474 baddr = bp->b_data;
475 error = uiomove(baddr + on, (int)n, uio);
476 }
477 switch (vp->v_type) {
478 case VREG:
479 break;
480 case VLNK:
481 n = 0;
482 break;
483 case VDIR:
484 if (np->n_flag & NQNFSNONCACHE)
485 bp->b_flags |= B_INVAL;
486 uio->uio_offset = curoff;
487 if (enough)
488 n = 0;
489 break;
490 default:
491 printf(" nfsbioread: type %x unexpected\n",vp->v_type);
492 }
493 if (got_buf)
494 brelse(bp);
495 } while (error == 0 && uio->uio_resid > 0 && n > 0);
496 return (error);
497 }
498
499 /*
500 * Vnode op for write using bio
501 */
502 int
503 nfs_write(v)
504 void *v;
505 {
506 struct vop_write_args /* {
507 struct vnode *a_vp;
508 struct uio *a_uio;
509 int a_ioflag;
510 struct ucred *a_cred;
511 } */ *ap = v;
512 struct uio *uio = ap->a_uio;
513 struct proc *p = uio->uio_procp;
514 struct vnode *vp = ap->a_vp;
515 struct nfsnode *np = VTONFS(vp);
516 struct ucred *cred = ap->a_cred;
517 int ioflag = ap->a_ioflag;
518 struct vattr vattr;
519 struct nfsmount *nmp = VFSTONFS(vp->v_mount);
520 void *win;
521 voff_t oldoff, origoff;
522 vsize_t bytelen;
523 int error = 0, iomode, must_commit;
524
525 #ifdef DIAGNOSTIC
526 if (uio->uio_rw != UIO_WRITE)
527 panic("nfs_write mode");
528 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
529 panic("nfs_write proc");
530 #endif
531 if (vp->v_type != VREG)
532 return (EIO);
533 if (np->n_flag & NWRITEERR) {
534 np->n_flag &= ~NWRITEERR;
535 return (np->n_error);
536 }
537 #ifndef NFS_V2_ONLY
538 if ((nmp->nm_flag & NFSMNT_NFSV3) &&
539 !(nmp->nm_iflag & NFSMNT_GOTFSINFO))
540 (void)nfs_fsinfo(nmp, vp, cred, p);
541 #endif
542 if (ioflag & (IO_APPEND | IO_SYNC)) {
543 if (np->n_flag & NMODIFIED) {
544 np->n_attrstamp = 0;
545 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
546 if (error)
547 return (error);
548 }
549 if (ioflag & IO_APPEND) {
550 np->n_attrstamp = 0;
551 error = VOP_GETATTR(vp, &vattr, cred, p);
552 if (error)
553 return (error);
554 uio->uio_offset = np->n_size;
555 }
556 }
557 if (uio->uio_offset < 0)
558 return (EINVAL);
559 if ((uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize)
560 return (EFBIG);
561 if (uio->uio_resid == 0)
562 return (0);
563 /*
564 * Maybe this should be above the vnode op call, but so long as
565 * file servers have no limits, i don't think it matters
566 */
567 if (p && uio->uio_offset + uio->uio_resid >
568 p->p_rlimit[RLIMIT_FSIZE].rlim_cur) {
569 psignal(p, SIGXFSZ);
570 return (EFBIG);
571 }
572
573 /*
574 * update the cached write creds for this node.
575 */
576
577 if (np->n_wcred) {
578 crfree(np->n_wcred);
579 }
580 np->n_wcred = cred;
581 crhold(cred);
582
583 if ((np->n_flag & NQNFSNONCACHE) && uio->uio_iovcnt == 1) {
584 iomode = NFSV3WRITE_FILESYNC;
585 error = nfs_writerpc(vp, uio, &iomode, &must_commit);
586 if (must_commit)
587 nfs_clearcommit(vp->v_mount);
588 return (error);
589 }
590
591 origoff = uio->uio_offset;
592 do {
593 oldoff = uio->uio_offset;
594 bytelen = uio->uio_resid;
595
596 #ifndef NFS_V2_ONLY
597 /*
598 * Check for a valid write lease.
599 */
600 if ((nmp->nm_flag & NFSMNT_NQNFS) &&
601 NQNFS_CKINVALID(vp, np, ND_WRITE)) {
602 do {
603 error = nqnfs_getlease(vp, ND_WRITE, cred, p);
604 } while (error == NQNFS_EXPIRED);
605 if (error)
606 return (error);
607 if (np->n_lrev != np->n_brev ||
608 (np->n_flag & NQNFSNONCACHE)) {
609 error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
610 if (error)
611 return (error);
612 np->n_brev = np->n_lrev;
613 }
614 }
615 #endif
616 nfsstats.biocache_writes++;
617
618 np->n_flag |= NMODIFIED;
619 if (np->n_size < uio->uio_offset + bytelen) {
620 np->n_size = uio->uio_offset + bytelen;
621 }
622 if ((uio->uio_offset & PAGE_MASK) == 0 &&
623 (bytelen & PAGE_MASK) == 0 &&
624 uio->uio_offset >= vp->v_size) {
625 win = ubc_alloc(&vp->v_uobj, uio->uio_offset, &bytelen,
626 UBC_WRITE | UBC_FAULTBUSY);
627 } else {
628 win = ubc_alloc(&vp->v_uobj, uio->uio_offset, &bytelen,
629 UBC_WRITE);
630 }
631 error = uiomove(win, bytelen, uio);
632 ubc_release(win, 0);
633 if (error) {
634 break;
635 }
636
637 /*
638 * update UVM's notion of the size now that we've
639 * copied the data into the vnode's pages.
640 */
641
642 if (vp->v_size < uio->uio_offset) {
643 uvm_vnp_setsize(vp, uio->uio_offset);
644 }
645
646 if ((oldoff & ~(nmp->nm_wsize - 1)) !=
647 (uio->uio_offset & ~(nmp->nm_wsize - 1))) {
648 simple_lock(&vp->v_interlock);
649 error = VOP_PUTPAGES(vp,
650 trunc_page(oldoff & ~(nmp->nm_wsize - 1)),
651 round_page((uio->uio_offset + nmp->nm_wsize - 1) &
652 ~(nmp->nm_wsize - 1)), PGO_CLEANIT);
653 }
654 } while (uio->uio_resid > 0);
655 if ((np->n_flag & NQNFSNONCACHE) || (ioflag & IO_SYNC)) {
656 simple_lock(&vp->v_interlock);
657 error = VOP_PUTPAGES(vp,
658 trunc_page(origoff & ~(nmp->nm_wsize - 1)),
659 round_page((uio->uio_offset + nmp->nm_wsize - 1) &
660 ~(nmp->nm_wsize - 1)),
661 PGO_CLEANIT | PGO_SYNCIO);
662 }
663 return error;
664 }
665
666 /*
667 * Get an nfs cache block.
668 * Allocate a new one if the block isn't currently in the cache
669 * and return the block marked busy. If the calling process is
670 * interrupted by a signal for an interruptible mount point, return
671 * NULL.
672 */
673 struct buf *
674 nfs_getcacheblk(vp, bn, size, p)
675 struct vnode *vp;
676 daddr_t bn;
677 int size;
678 struct proc *p;
679 {
680 struct buf *bp;
681 struct nfsmount *nmp = VFSTONFS(vp->v_mount);
682
683 if (nmp->nm_flag & NFSMNT_INT) {
684 bp = getblk(vp, bn, size, PCATCH, 0);
685 while (bp == NULL) {
686 if (nfs_sigintr(nmp, NULL, p))
687 return (NULL);
688 bp = getblk(vp, bn, size, 0, 2 * hz);
689 }
690 } else
691 bp = getblk(vp, bn, size, 0, 0);
692 return (bp);
693 }
694
695 /*
696 * Flush and invalidate all dirty buffers. If another process is already
697 * doing the flush, just wait for completion.
698 */
699 int
700 nfs_vinvalbuf(vp, flags, cred, p, intrflg)
701 struct vnode *vp;
702 int flags;
703 struct ucred *cred;
704 struct proc *p;
705 int intrflg;
706 {
707 struct nfsnode *np = VTONFS(vp);
708 struct nfsmount *nmp = VFSTONFS(vp->v_mount);
709 int error = 0, slpflag, slptimeo;
710
711 if ((nmp->nm_flag & NFSMNT_INT) == 0)
712 intrflg = 0;
713 if (intrflg) {
714 slpflag = PCATCH;
715 slptimeo = 2 * hz;
716 } else {
717 slpflag = 0;
718 slptimeo = 0;
719 }
720 /*
721 * First wait for any other process doing a flush to complete.
722 */
723 while (np->n_flag & NFLUSHINPROG) {
724 np->n_flag |= NFLUSHWANT;
725 error = tsleep((caddr_t)&np->n_flag, PRIBIO + 2, "nfsvinval",
726 slptimeo);
727 if (error && intrflg && nfs_sigintr(nmp, NULL, p))
728 return (EINTR);
729 }
730
731 /*
732 * Now, flush as required.
733 */
734 np->n_flag |= NFLUSHINPROG;
735 error = vinvalbuf(vp, flags, cred, p, slpflag, 0);
736 while (error) {
737 if (intrflg && nfs_sigintr(nmp, NULL, p)) {
738 np->n_flag &= ~NFLUSHINPROG;
739 if (np->n_flag & NFLUSHWANT) {
740 np->n_flag &= ~NFLUSHWANT;
741 wakeup((caddr_t)&np->n_flag);
742 }
743 return (EINTR);
744 }
745 error = vinvalbuf(vp, flags, cred, p, 0, slptimeo);
746 }
747 np->n_flag &= ~(NMODIFIED | NFLUSHINPROG);
748 if (np->n_flag & NFLUSHWANT) {
749 np->n_flag &= ~NFLUSHWANT;
750 wakeup((caddr_t)&np->n_flag);
751 }
752 return (0);
753 }
754
755 /*
756 * Initiate asynchronous I/O. Return an error if no nfsiods are available.
757 * This is mainly to avoid queueing async I/O requests when the nfsiods
758 * are all hung on a dead server.
759 */
760
761 int
762 nfs_asyncio(bp)
763 struct buf *bp;
764 {
765 int i;
766 struct nfsmount *nmp;
767 int gotiod, slpflag = 0, slptimeo = 0, error;
768
769 if (nfs_numasync == 0)
770 return (EIO);
771
772 nmp = VFSTONFS(bp->b_vp->v_mount);
773 again:
774 if (nmp->nm_flag & NFSMNT_INT)
775 slpflag = PCATCH;
776 gotiod = FALSE;
777
778 /*
779 * Find a free iod to process this request.
780 */
781
782 for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
783 if (nfs_iodwant[i]) {
784 /*
785 * Found one, so wake it up and tell it which
786 * mount to process.
787 */
788 nfs_iodwant[i] = NULL;
789 nfs_iodmount[i] = nmp;
790 nmp->nm_bufqiods++;
791 wakeup((caddr_t)&nfs_iodwant[i]);
792 gotiod = TRUE;
793 break;
794 }
795
796 /*
797 * If none are free, we may already have an iod working on this mount
798 * point. If so, it will process our request.
799 */
800
801 if (!gotiod && nmp->nm_bufqiods > 0)
802 gotiod = TRUE;
803
804 /*
805 * If we have an iod which can process the request, then queue
806 * the buffer.
807 */
808
809 if (gotiod) {
810
811 /*
812 * Ensure that the queue never grows too large.
813 */
814
815 while (nmp->nm_bufqlen >= 2*nfs_numasync) {
816 nmp->nm_bufqwant = TRUE;
817 error = tsleep(&nmp->nm_bufq, slpflag | PRIBIO,
818 "nfsaio", slptimeo);
819 if (error) {
820 if (nfs_sigintr(nmp, NULL, curproc))
821 return (EINTR);
822 if (slpflag == PCATCH) {
823 slpflag = 0;
824 slptimeo = 2 * hz;
825 }
826 }
827
828 /*
829 * We might have lost our iod while sleeping,
830 * so check and loop if nescessary.
831 */
832
833 if (nmp->nm_bufqiods == 0)
834 goto again;
835 }
836 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist);
837 nmp->nm_bufqlen++;
838 return (0);
839 }
840
841 /*
842 * All the iods are busy on other mounts, so return EIO to
843 * force the caller to process the i/o synchronously.
844 */
845
846 return (EIO);
847 }
848
849 /*
850 * Do an I/O operation to/from a cache block. This may be called
851 * synchronously or from an nfsiod.
852 */
853 int
854 nfs_doio(bp, p)
855 struct buf *bp;
856 struct proc *p;
857 {
858 struct uio *uiop;
859 struct vnode *vp;
860 struct nfsnode *np;
861 struct nfsmount *nmp;
862 int error = 0, diff, len, iomode, must_commit = 0;
863 int pushedrange;
864 struct uio uio;
865 struct iovec io;
866 off_t off, cnt;
867 struct uvm_object *uobj;
868 UVMHIST_FUNC("nfs_doio"); UVMHIST_CALLED(ubchist);
869
870 vp = bp->b_vp;
871 uobj = &vp->v_uobj;
872 np = VTONFS(vp);
873 nmp = VFSTONFS(vp->v_mount);
874 uiop = &uio;
875 uiop->uio_iov = &io;
876 uiop->uio_iovcnt = 1;
877 uiop->uio_segflg = UIO_SYSSPACE;
878 uiop->uio_procp = p;
879
880 /*
881 * Historically, paging was done with physio, but no more...
882 */
883 if (bp->b_flags & B_PHYS) {
884 /*
885 * ...though reading /dev/drum still gets us here.
886 */
887 io.iov_len = uiop->uio_resid = bp->b_bcount;
888 /* mapping was done by vmapbuf() */
889 io.iov_base = bp->b_data;
890 uiop->uio_offset = ((off_t)bp->b_blkno) << DEV_BSHIFT;
891 if (bp->b_flags & B_READ) {
892 uiop->uio_rw = UIO_READ;
893 nfsstats.read_physios++;
894 error = nfs_readrpc(vp, uiop);
895 } else {
896 iomode = NFSV3WRITE_DATASYNC;
897 uiop->uio_rw = UIO_WRITE;
898 nfsstats.write_physios++;
899 error = nfs_writerpc(vp, uiop, &iomode, &must_commit);
900 }
901 if (error) {
902 bp->b_flags |= B_ERROR;
903 bp->b_error = error;
904 }
905 } else if (bp->b_flags & B_READ) {
906 io.iov_len = uiop->uio_resid = bp->b_bcount;
907 io.iov_base = bp->b_data;
908 uiop->uio_rw = UIO_READ;
909 switch (vp->v_type) {
910 case VREG:
911 uiop->uio_offset = ((off_t)bp->b_blkno) << DEV_BSHIFT;
912 nfsstats.read_bios++;
913 error = nfs_readrpc(vp, uiop);
914 if (!error && uiop->uio_resid) {
915
916 /*
917 * If len > 0, there is a hole in the file and
918 * no writes after the hole have been pushed to
919 * the server yet.
920 * Just zero fill the rest of the valid area.
921 */
922
923 diff = bp->b_bcount - uiop->uio_resid;
924 len = np->n_size - ((((off_t)bp->b_blkno) << DEV_BSHIFT)
925 + diff);
926 if (len > 0) {
927 len = MIN(len, uiop->uio_resid);
928 memset((char *)bp->b_data + diff, 0, len);
929 }
930 }
931 if (p && (vp->v_flag & VTEXT) &&
932 (((nmp->nm_flag & NFSMNT_NQNFS) &&
933 NQNFS_CKINVALID(vp, np, ND_READ) &&
934 np->n_lrev != np->n_brev) ||
935 (!(nmp->nm_flag & NFSMNT_NQNFS) &&
936 np->n_mtime != np->n_vattr->va_mtime.tv_sec))) {
937 uprintf("Process killed due to "
938 "text file modification\n");
939 psignal(p, SIGKILL);
940 p->p_holdcnt++;
941 }
942 break;
943 case VLNK:
944 uiop->uio_offset = (off_t)0;
945 nfsstats.readlink_bios++;
946 error = nfs_readlinkrpc(vp, uiop, curproc->p_ucred);
947 break;
948 case VDIR:
949 nfsstats.readdir_bios++;
950 uiop->uio_offset = bp->b_dcookie;
951 if (nmp->nm_flag & NFSMNT_RDIRPLUS) {
952 error = nfs_readdirplusrpc(vp, uiop, curproc->p_ucred);
953 if (error == NFSERR_NOTSUPP)
954 nmp->nm_flag &= ~NFSMNT_RDIRPLUS;
955 }
956 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0)
957 error = nfs_readdirrpc(vp, uiop, curproc->p_ucred);
958 if (!error) {
959 bp->b_dcookie = uiop->uio_offset;
960 }
961 break;
962 default:
963 printf("nfs_doio: type %x unexpected\n",vp->v_type);
964 break;
965 }
966 if (error) {
967 bp->b_flags |= B_ERROR;
968 bp->b_error = error;
969 }
970 } else {
971 int i, npages = bp->b_bufsize >> PAGE_SHIFT;
972 struct vm_page *pgs[npages];
973 boolean_t needcommit = TRUE;
974
975 if ((bp->b_flags & B_ASYNC) != 0 && NFS_ISV3(vp)) {
976 iomode = NFSV3WRITE_UNSTABLE;
977 } else {
978 iomode = NFSV3WRITE_FILESYNC;
979 }
980
981 for (i = 0; i < npages; i++) {
982 pgs[i] = uvm_pageratop((vaddr_t)bp->b_data +
983 (i << PAGE_SHIFT));
984 if ((pgs[i]->flags & PG_NEEDCOMMIT) == 0) {
985 needcommit = FALSE;
986 }
987 }
988 if (!needcommit && iomode == NFSV3WRITE_UNSTABLE) {
989 for (i = 0; i < npages; i++) {
990 pgs[i]->flags |= PG_NEEDCOMMIT | PG_RDONLY;
991 pmap_page_protect(pgs[i], VM_PROT_READ);
992 }
993 }
994
995 uiop->uio_offset = (((off_t)bp->b_blkno) << DEV_BSHIFT);
996 off = uiop->uio_offset;
997 cnt = bp->b_bcount;
998
999 /*
1000 * Send the data to the server if necessary,
1001 * otherwise just send a commit rpc.
1002 */
1003
1004 if (needcommit) {
1005
1006 /*
1007 * If the buffer is in the range that we already committed,
1008 * there's nothing to do.
1009 *
1010 * If it's in the range that we need to commit, push the
1011 * whole range at once, otherwise only push the buffer.
1012 * In both these cases, acquire the commit lock to avoid
1013 * other processes modifying the range.
1014 */
1015
1016 lockmgr(&np->n_commitlock, LK_EXCLUSIVE, NULL);
1017 if (!nfs_in_committed_range(vp, off, bp->b_bcount)) {
1018 if (nfs_in_tobecommitted_range(vp, off, bp->b_bcount)) {
1019 pushedrange = 1;
1020 off = np->n_pushlo;
1021 cnt = np->n_pushhi - np->n_pushlo;
1022 } else {
1023 pushedrange = 0;
1024 }
1025 error = nfs_commit(vp, off, cnt, curproc);
1026 if (error == 0) {
1027 if (pushedrange) {
1028 nfs_merge_commit_ranges(vp);
1029 } else {
1030 nfs_add_committed_range(vp, off, cnt);
1031 }
1032 }
1033 }
1034 lockmgr(&np->n_commitlock, LK_RELEASE, NULL);
1035 if (!error) {
1036 bp->b_resid = 0;
1037 simple_lock(&uobj->vmobjlock);
1038 for (i = 0; i < npages; i++) {
1039 pgs[i]->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY);
1040 }
1041 simple_unlock(&uobj->vmobjlock);
1042 biodone(bp);
1043 return (0);
1044 } else if (error == NFSERR_STALEWRITEVERF) {
1045 nfs_clearcommit(bp->b_vp->v_mount);
1046 }
1047 }
1048 io.iov_base = bp->b_data;
1049 io.iov_len = uiop->uio_resid = bp->b_bcount;
1050 uiop->uio_rw = UIO_WRITE;
1051 nfsstats.write_bios++;
1052 error = nfs_writerpc(vp, uiop, &iomode, &must_commit);
1053 if (!error && iomode == NFSV3WRITE_UNSTABLE) {
1054 lockmgr(&np->n_commitlock, LK_EXCLUSIVE, NULL);
1055 nfs_add_tobecommitted_range(vp, off, cnt);
1056 simple_lock(&uobj->vmobjlock);
1057 for (i = 0; i < npages; i++) {
1058 pgs[i]->flags &= ~PG_CLEAN;
1059 }
1060 simple_unlock(&uobj->vmobjlock);
1061 if (np->n_pushhi - np->n_pushlo > nfs_commitsize) {
1062 off = np->n_pushlo;
1063 cnt = nfs_commitsize >> 1;
1064 error = nfs_commit(vp, off, cnt, curproc);
1065 if (!error) {
1066 nfs_add_committed_range(vp, off, cnt);
1067 nfs_del_tobecommitted_range(vp, off, cnt);
1068 }
1069 }
1070 lockmgr(&np->n_commitlock, LK_RELEASE, NULL);
1071 } else if (!error && needcommit) {
1072 lockmgr(&np->n_commitlock, LK_EXCLUSIVE, NULL);
1073 nfs_del_committed_range(vp, off, cnt);
1074 lockmgr(&np->n_commitlock, LK_RELEASE, NULL);
1075 simple_lock(&uobj->vmobjlock);
1076 for (i = 0; i < npages; i++) {
1077 pgs[i]->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY);
1078 }
1079 simple_unlock(&uobj->vmobjlock);
1080 } else {
1081 if (error) {
1082 bp->b_flags |= B_ERROR;
1083 bp->b_error = np->n_error = error;
1084 np->n_flag |= NWRITEERR;
1085 }
1086 }
1087 }
1088 bp->b_resid = uiop->uio_resid;
1089 if (must_commit || (error == NFSERR_STALEWRITEVERF)) {
1090 nfs_clearcommit(vp->v_mount);
1091 }
1092 biodone(bp);
1093 return (error);
1094 }
1095
1096 /*
1097 * Vnode op for VM getpages.
1098 */
1099
1100 int
1101 nfs_getpages(v)
1102 void *v;
1103 {
1104 struct vop_getpages_args /* {
1105 struct vnode *a_vp;
1106 voff_t a_offset;
1107 struct vm_page **a_m;
1108 int *a_count;
1109 int a_centeridx;
1110 vm_prot_t a_access_type;
1111 int a_advice;
1112 int a_flags;
1113 } */ *ap = v;
1114
1115 struct vnode *vp = ap->a_vp;
1116 struct uvm_object *uobj = &vp->v_uobj;
1117 struct nfsnode *np = VTONFS(vp);
1118 const int npages = *ap->a_count;
1119 struct vm_page *pg, **pgs, *opgs[npages];
1120 off_t origoffset, len;
1121 int i, error;
1122 boolean_t v3 = NFS_ISV3(vp);
1123 boolean_t write = (ap->a_access_type & VM_PROT_WRITE) != 0;
1124 boolean_t locked = (ap->a_flags & PGO_LOCKED) != 0;
1125
1126 /*
1127 * update the cached read creds for this node.
1128 */
1129
1130 if (np->n_rcred) {
1131 crfree(np->n_rcred);
1132 }
1133 np->n_rcred = curproc->p_ucred;
1134 crhold(np->n_rcred);
1135
1136 /*
1137 * if we have delayed truncation and it's safe, do it now.
1138 */
1139
1140 if (ap->a_flags & PGO_SYNCIO) {
1141 nfs_delayedtruncate(vp);
1142 }
1143
1144 /*
1145 * call the genfs code to get the pages. `pgs' may be NULL
1146 * when doing read-ahead.
1147 */
1148
1149 pgs = ap->a_m;
1150 if (write && locked && v3) {
1151 KASSERT(pgs != NULL);
1152 #ifdef DEBUG
1153
1154 /*
1155 * If PGO_LOCKED is set, real pages shouldn't exists
1156 * in the array.
1157 */
1158
1159 for (i = 0; i < npages; i++)
1160 KDASSERT(pgs[i] == NULL || pgs[i] == PGO_DONTCARE);
1161 #endif
1162 memcpy(opgs, pgs, npages * sizeof(struct vm_pages *));
1163 }
1164 error = genfs_getpages(v);
1165 if (error) {
1166 return (error);
1167 }
1168
1169 /*
1170 * for read faults where the nfs node is not yet marked NMODIFIED,
1171 * set PG_RDONLY on the pages so that we come back here if someone
1172 * tries to modify later via the mapping that will be entered for
1173 * this fault.
1174 */
1175
1176 if (!write && (np->n_flag & NMODIFIED) == 0 && pgs != NULL) {
1177 if (!locked) {
1178 simple_lock(&uobj->vmobjlock);
1179 }
1180 for (i = 0; i < npages; i++) {
1181 pg = pgs[i];
1182 if (pg == NULL || pg == PGO_DONTCARE) {
1183 continue;
1184 }
1185 pg->flags |= PG_RDONLY;
1186 }
1187 if (!locked) {
1188 simple_unlock(&uobj->vmobjlock);
1189 }
1190 }
1191 if (!write) {
1192 return (0);
1193 }
1194
1195 /*
1196 * this is a write fault, update the commit info.
1197 */
1198
1199 origoffset = ap->a_offset;
1200 len = npages << PAGE_SHIFT;
1201
1202 if (v3) {
1203 error = lockmgr(&np->n_commitlock,
1204 LK_EXCLUSIVE | (locked ? LK_NOWAIT : 0), NULL);
1205 if (error) {
1206 KASSERT(locked != 0);
1207
1208 /*
1209 * Since PGO_LOCKED is set, we need to unbusy
1210 * all pages fetched by genfs_getpages() above,
1211 * tell the caller that there are no pages
1212 * available and put back original pgs array.
1213 */
1214
1215 uvm_lock_pageq();
1216 uvm_page_unbusy(pgs, npages);
1217 uvm_unlock_pageq();
1218 *ap->a_count = 0;
1219 memcpy(pgs, opgs,
1220 npages * sizeof(struct vm_pages *));
1221 return (error);
1222 }
1223 nfs_del_committed_range(vp, origoffset, len);
1224 nfs_del_tobecommitted_range(vp, origoffset, len);
1225 }
1226 np->n_flag |= NMODIFIED;
1227 if (!locked) {
1228 simple_lock(&uobj->vmobjlock);
1229 }
1230 for (i = 0; i < npages; i++) {
1231 pg = pgs[i];
1232 if (pg == NULL || pg == PGO_DONTCARE) {
1233 continue;
1234 }
1235 pg->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY);
1236 }
1237 if (!locked) {
1238 simple_unlock(&uobj->vmobjlock);
1239 }
1240 if (v3) {
1241 lockmgr(&np->n_commitlock, LK_RELEASE, NULL);
1242 }
1243 return (0);
1244 }
1245