1/*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Rick Macklem at The University of Guelph. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95 33 */ 34 35#include <sys/cdefs.h> 36__FBSDID("$FreeBSD$"); 37 38#include "opt_kdtrace.h" 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/mbuf.h> 46#include <sys/mount.h> 47#include <sys/proc.h> 48#include <sys/vmmeter.h> 49#include <sys/vnode.h> 50 51#include <vm/vm.h> 52#include <vm/vm_param.h> 53#include <vm/vm_extern.h> 54#include <vm/vm_page.h> 55#include <vm/vm_object.h> 56#include <vm/vm_pager.h> 57#include <vm/vnode_pager.h> 58 59#include <nfs/nfsproto.h> 60#include <nfsclient/nfs.h> 61#include <nfsclient/nfsmount.h> 62#include <nfsclient/nfsnode.h> 63#include <nfs/nfs_kdtrace.h> 64 65static struct buf *nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, 66 struct thread *td); 67static int nfs_directio_write(struct vnode *vp, struct uio *uiop, 68 struct ucred *cred, int ioflag); 69 70extern int nfs_directio_enable; 71extern int nfs_directio_allow_mmap; 72 73/* 74 * Vnode op for VM getpages. 75 */ 76int 77nfs_getpages(struct vop_getpages_args *ap) 78{ 79 int i, error, nextoff, size, toff, count, npages; 80 struct uio uio; 81 struct iovec iov; 82 vm_offset_t kva; 83 struct buf *bp; 84 struct vnode *vp; 85 struct thread *td; 86 struct ucred *cred; 87 struct nfsmount *nmp; 88 vm_object_t object; 89 vm_page_t *pages; 90 struct nfsnode *np; 91 92 vp = ap->a_vp; 93 np = VTONFS(vp); 94 td = curthread; /* XXX */ 95 cred = curthread->td_ucred; /* XXX */ 96 nmp = VFSTONFS(vp->v_mount); 97 pages = ap->a_m; 98 count = ap->a_count; 99 100 if ((object = vp->v_object) == NULL) { 101 nfs_printf("nfs_getpages: called with non-merged cache vnode??\n"); 102 return (VM_PAGER_ERROR); 103 } 104 105 if (nfs_directio_enable && !nfs_directio_allow_mmap) { 106 mtx_lock(&np->n_mtx); 107 if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 108 mtx_unlock(&np->n_mtx); 109 nfs_printf("nfs_getpages: called on non-cacheable vnode??\n"); 110 return (VM_PAGER_ERROR); 111 } else 112 mtx_unlock(&np->n_mtx); 113 } 114 115 mtx_lock(&nmp->nm_mtx); 116 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 117 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 118 mtx_unlock(&nmp->nm_mtx); 119 /* We'll never get here for v4, because we always have fsinfo */ 120 (void)nfs_fsinfo(nmp, vp, cred, td); 121 } else 122 mtx_unlock(&nmp->nm_mtx); 123 124 npages = btoc(count); 125 126 /* 127 * If the requested page is partially valid, just return it and 128 * allow the pager to zero-out the blanks. Partially valid pages 129 * can only occur at the file EOF. 130 */ 131 VM_OBJECT_LOCK(object); 132 if (pages[ap->a_reqpage]->valid != 0) { 133 for (i = 0; i < npages; ++i) { 134 if (i != ap->a_reqpage) { 135 vm_page_lock(pages[i]); 136 vm_page_free(pages[i]); 137 vm_page_unlock(pages[i]); 138 } 139 } 140 VM_OBJECT_UNLOCK(object); 141 return (0); 142 } 143 VM_OBJECT_UNLOCK(object); 144 145 /* 146 * We use only the kva address for the buffer, but this is extremely 147 * convienient and fast. 148 */ 149 bp = getpbuf(&nfs_pbuf_freecnt); 150 151 kva = (vm_offset_t) bp->b_data; 152 pmap_qenter(kva, pages, npages); 153 PCPU_INC(cnt.v_vnodein); 154 PCPU_ADD(cnt.v_vnodepgsin, npages); 155 156 iov.iov_base = (caddr_t) kva; 157 iov.iov_len = count; 158 uio.uio_iov = &iov; 159 uio.uio_iovcnt = 1; 160 uio.uio_offset = IDX_TO_OFF(pages[0]->pindex); 161 uio.uio_resid = count; 162 uio.uio_segflg = UIO_SYSSPACE; 163 uio.uio_rw = UIO_READ; 164 uio.uio_td = td; 165 166 error = (nmp->nm_rpcops->nr_readrpc)(vp, &uio, cred); 167 pmap_qremove(kva, npages); 168 169 relpbuf(bp, &nfs_pbuf_freecnt); 170 171 if (error && (uio.uio_resid == count)) { 172 nfs_printf("nfs_getpages: error %d\n", error); 173 VM_OBJECT_LOCK(object); 174 for (i = 0; i < npages; ++i) { 175 if (i != ap->a_reqpage) { 176 vm_page_lock(pages[i]); 177 vm_page_free(pages[i]); 178 vm_page_unlock(pages[i]); 179 } 180 } 181 VM_OBJECT_UNLOCK(object); 182 return (VM_PAGER_ERROR); 183 } 184 185 /* 186 * Calculate the number of bytes read and validate only that number 187 * of bytes. Note that due to pending writes, size may be 0. This 188 * does not mean that the remaining data is invalid! 189 */ 190 191 size = count - uio.uio_resid; 192 VM_OBJECT_LOCK(object); 193 for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { 194 vm_page_t m; 195 nextoff = toff + PAGE_SIZE; 196 m = pages[i]; 197 198 if (nextoff <= size) { 199 /* 200 * Read operation filled an entire page 201 */ 202 m->valid = VM_PAGE_BITS_ALL; 203 KASSERT(m->dirty == 0, 204 ("nfs_getpages: page %p is dirty", m)); 205 } else if (size > toff) { 206 /* 207 * Read operation filled a partial page. 208 */ 209 m->valid = 0; 210 vm_page_set_valid(m, 0, size - toff); 211 KASSERT(m->dirty == 0, 212 ("nfs_getpages: page %p is dirty", m)); 213 } else { 214 /* 215 * Read operation was short. If no error 216 * occured we may have hit a zero-fill 217 * section. We leave valid set to 0, and page 218 * is freed by vm_page_readahead_finish() if 219 * its index is not equal to requested, or 220 * page is zeroed and set valid by 221 * vm_pager_get_pages() for requested page. 222 */ 223 ; 224 } 225 if (i != ap->a_reqpage) 226 vm_page_readahead_finish(m); 227 } 228 VM_OBJECT_UNLOCK(object); 229 return (0); 230} 231 232/* 233 * Vnode op for VM putpages. 234 */ 235int 236nfs_putpages(struct vop_putpages_args *ap) 237{ 238 struct uio uio; 239 struct iovec iov; 240 vm_offset_t kva; 241 struct buf *bp; 242 int iomode, must_commit, i, error, npages, count; 243 off_t offset; 244 int *rtvals; 245 struct vnode *vp; 246 struct thread *td; 247 struct ucred *cred; 248 struct nfsmount *nmp; 249 struct nfsnode *np; 250 vm_page_t *pages; 251 252 vp = ap->a_vp; 253 np = VTONFS(vp); 254 td = curthread; /* XXX */ 255 /* Set the cred to n_writecred for the write rpcs. */ 256 if (np->n_writecred != NULL) 257 cred = crhold(np->n_writecred); 258 else 259 cred = crhold(curthread->td_ucred); /* XXX */ 260 nmp = VFSTONFS(vp->v_mount); 261 pages = ap->a_m; 262 count = ap->a_count; 263 rtvals = ap->a_rtvals; 264 npages = btoc(count); 265 offset = IDX_TO_OFF(pages[0]->pindex); 266 267 mtx_lock(&nmp->nm_mtx); 268 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 269 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 270 mtx_unlock(&nmp->nm_mtx); 271 (void)nfs_fsinfo(nmp, vp, cred, td); 272 } else 273 mtx_unlock(&nmp->nm_mtx); 274 275 mtx_lock(&np->n_mtx); 276 if (nfs_directio_enable && !nfs_directio_allow_mmap && 277 (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 278 mtx_unlock(&np->n_mtx); 279 nfs_printf("nfs_putpages: called on noncache-able vnode??\n"); 280 mtx_lock(&np->n_mtx); 281 } 282 283 for (i = 0; i < npages; i++) 284 rtvals[i] = VM_PAGER_ERROR; 285 286 /* 287 * When putting pages, do not extend file past EOF. 288 */ 289 if (offset + count > np->n_size) { 290 count = np->n_size - offset; 291 if (count < 0) 292 count = 0; 293 } 294 mtx_unlock(&np->n_mtx); 295 296 /* 297 * We use only the kva address for the buffer, but this is extremely 298 * convienient and fast. 299 */ 300 bp = getpbuf(&nfs_pbuf_freecnt); 301 302 kva = (vm_offset_t) bp->b_data; 303 pmap_qenter(kva, pages, npages); 304 PCPU_INC(cnt.v_vnodeout); 305 PCPU_ADD(cnt.v_vnodepgsout, count); 306 307 iov.iov_base = (caddr_t) kva; 308 iov.iov_len = count; 309 uio.uio_iov = &iov; 310 uio.uio_iovcnt = 1; 311 uio.uio_offset = offset; 312 uio.uio_resid = count; 313 uio.uio_segflg = UIO_SYSSPACE; 314 uio.uio_rw = UIO_WRITE; 315 uio.uio_td = td; 316 317 if ((ap->a_sync & VM_PAGER_PUT_SYNC) == 0) 318 iomode = NFSV3WRITE_UNSTABLE; 319 else 320 iomode = NFSV3WRITE_FILESYNC; 321 322 error = (nmp->nm_rpcops->nr_writerpc)(vp, &uio, cred, &iomode, &must_commit); 323 crfree(cred); 324 325 pmap_qremove(kva, npages); 326 relpbuf(bp, &nfs_pbuf_freecnt); 327 328 if (!error) { 329 vnode_pager_undirty_pages(pages, rtvals, count - uio.uio_resid); 330 if (must_commit) { 331 nfs_clearcommit(vp->v_mount); 332 } 333 } 334 return rtvals[0]; 335} 336 337/* 338 * For nfs, cache consistency can only be maintained approximately. 339 * Although RFC1094 does not specify the criteria, the following is 340 * believed to be compatible with the reference port. 341 * For nfs: 342 * If the file's modify time on the server has changed since the 343 * last read rpc or you have written to the file, 344 * you may have lost data cache consistency with the 345 * server, so flush all of the file's data out of the cache. 346 * Then force a getattr rpc to ensure that you have up to date 347 * attributes. 348 * NB: This implies that cache data can be read when up to 349 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 350 * attributes this could be forced by setting n_attrstamp to 0 before 351 * the VOP_GETATTR() call. 352 */ 353static inline int 354nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred) 355{ 356 int error = 0; 357 struct vattr vattr; 358 struct nfsnode *np = VTONFS(vp); 359 int old_lock; 360 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 361 362 /* 363 * Grab the exclusive lock before checking whether the cache is 364 * consistent. 365 * XXX - We can make this cheaper later (by acquiring cheaper locks). 366 * But for now, this suffices. 367 */ 368 old_lock = nfs_upgrade_vnlock(vp); 369 if (vp->v_iflag & VI_DOOMED) { 370 nfs_downgrade_vnlock(vp, old_lock); 371 return (EBADF); 372 } 373 374 mtx_lock(&np->n_mtx); 375 if (np->n_flag & NMODIFIED) { 376 mtx_unlock(&np->n_mtx); 377 if (vp->v_type != VREG) { 378 if (vp->v_type != VDIR) 379 panic("nfs: bioread, not dir"); 380 (nmp->nm_rpcops->nr_invaldir)(vp); 381 error = nfs_vinvalbuf(vp, V_SAVE, td, 1); 382 if (error) 383 goto out; 384 } 385 np->n_attrstamp = 0; 386 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 387 error = VOP_GETATTR(vp, &vattr, cred); 388 if (error) 389 goto out; 390 mtx_lock(&np->n_mtx); 391 np->n_mtime = vattr.va_mtime; 392 mtx_unlock(&np->n_mtx); 393 } else { 394 mtx_unlock(&np->n_mtx); 395 error = VOP_GETATTR(vp, &vattr, cred); 396 if (error) 397 return (error); 398 mtx_lock(&np->n_mtx); 399 if ((np->n_flag & NSIZECHANGED) 400 || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) { 401 mtx_unlock(&np->n_mtx); 402 if (vp->v_type == VDIR) 403 (nmp->nm_rpcops->nr_invaldir)(vp); 404 error = nfs_vinvalbuf(vp, V_SAVE, td, 1); 405 if (error) 406 goto out; 407 mtx_lock(&np->n_mtx); 408 np->n_mtime = vattr.va_mtime; 409 np->n_flag &= ~NSIZECHANGED; 410 } 411 mtx_unlock(&np->n_mtx); 412 } 413out: 414 nfs_downgrade_vnlock(vp, old_lock); 415 return error; 416} 417 418/* 419 * Vnode op for read using bio 420 */ 421int 422nfs_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) 423{ 424 struct nfsnode *np = VTONFS(vp); 425 int biosize, i; 426 struct buf *bp, *rabp; 427 struct thread *td; 428 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 429 daddr_t lbn, rabn; 430 off_t end; 431 int bcount; 432 int seqcount; 433 int nra, error = 0, n = 0, on = 0; 434 435 KASSERT(uio->uio_rw == UIO_READ, ("nfs_read mode")); 436 if (uio->uio_resid == 0) 437 return (0); 438 if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ 439 return (EINVAL); 440 td = uio->uio_td; 441 442 mtx_lock(&nmp->nm_mtx); 443 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 444 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 445 mtx_unlock(&nmp->nm_mtx); 446 (void)nfs_fsinfo(nmp, vp, cred, td); 447 } else 448 mtx_unlock(&nmp->nm_mtx); 449 450 end = uio->uio_offset + uio->uio_resid; 451 if (vp->v_type != VDIR && 452 (end > nmp->nm_maxfilesize || end < uio->uio_offset)) 453 return (EFBIG); 454 455 if (nfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG)) 456 /* No caching/ no readaheads. Just read data into the user buffer */ 457 return nfs_readrpc(vp, uio, cred); 458 459 biosize = vp->v_bufobj.bo_bsize; 460 seqcount = (int)((off_t)(ioflag >> IO_SEQSHIFT) * biosize / BKVASIZE); 461 462 error = nfs_bioread_check_cons(vp, td, cred); 463 if (error) 464 return error; 465 466 do { 467 u_quad_t nsize; 468 469 mtx_lock(&np->n_mtx); 470 nsize = np->n_size; 471 mtx_unlock(&np->n_mtx); 472 473 switch (vp->v_type) { 474 case VREG: 475 nfsstats.biocache_reads++; 476 lbn = uio->uio_offset / biosize; 477 on = uio->uio_offset & (biosize - 1); 478 479 /* 480 * Start the read ahead(s), as required. 481 */ 482 if (nmp->nm_readahead > 0) { 483 for (nra = 0; nra < nmp->nm_readahead && nra < seqcount && 484 (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) { 485 rabn = lbn + 1 + nra; 486 if (incore(&vp->v_bufobj, rabn) == NULL) { 487 rabp = nfs_getcacheblk(vp, rabn, biosize, td); 488 if (!rabp) { 489 error = nfs_sigintr(nmp, td); 490 return (error ? error : EINTR); 491 } 492 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 493 rabp->b_flags |= B_ASYNC; 494 rabp->b_iocmd = BIO_READ; 495 vfs_busy_pages(rabp, 0); 496 if (nfs_asyncio(nmp, rabp, cred, td)) { 497 rabp->b_flags |= B_INVAL; 498 rabp->b_ioflags |= BIO_ERROR; 499 vfs_unbusy_pages(rabp); 500 brelse(rabp); 501 break; 502 } 503 } else { 504 brelse(rabp); 505 } 506 } 507 } 508 } 509 510 /* Note that bcount is *not* DEV_BSIZE aligned. */ 511 bcount = biosize; 512 if ((off_t)lbn * biosize >= nsize) { 513 bcount = 0; 514 } else if ((off_t)(lbn + 1) * biosize > nsize) { 515 bcount = nsize - (off_t)lbn * biosize; 516 } 517 bp = nfs_getcacheblk(vp, lbn, bcount, td); 518 519 if (!bp) { 520 error = nfs_sigintr(nmp, td); 521 return (error ? error : EINTR); 522 } 523 524 /* 525 * If B_CACHE is not set, we must issue the read. If this 526 * fails, we return an error. 527 */ 528 529 if ((bp->b_flags & B_CACHE) == 0) { 530 bp->b_iocmd = BIO_READ; 531 vfs_busy_pages(bp, 0); 532 error = nfs_doio(vp, bp, cred, td); 533 if (error) { 534 brelse(bp); 535 return (error); 536 } 537 } 538 539 /* 540 * on is the offset into the current bp. Figure out how many 541 * bytes we can copy out of the bp. Note that bcount is 542 * NOT DEV_BSIZE aligned. 543 * 544 * Then figure out how many bytes we can copy into the uio. 545 */ 546 547 n = 0; 548 if (on < bcount) 549 n = MIN((unsigned)(bcount - on), uio->uio_resid); 550 break; 551 case VLNK: 552 nfsstats.biocache_readlinks++; 553 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, td); 554 if (!bp) { 555 error = nfs_sigintr(nmp, td); 556 return (error ? error : EINTR); 557 } 558 if ((bp->b_flags & B_CACHE) == 0) { 559 bp->b_iocmd = BIO_READ; 560 vfs_busy_pages(bp, 0); 561 error = nfs_doio(vp, bp, cred, td); 562 if (error) { 563 bp->b_ioflags |= BIO_ERROR; 564 brelse(bp); 565 return (error); 566 } 567 } 568 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 569 on = 0; 570 break; 571 case VDIR: 572 nfsstats.biocache_readdirs++; 573 if (np->n_direofoffset 574 && uio->uio_offset >= np->n_direofoffset) { 575 return (0); 576 } 577 lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ; 578 on = uio->uio_offset & (NFS_DIRBLKSIZ - 1); 579 bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, td); 580 if (!bp) { 581 error = nfs_sigintr(nmp, td); 582 return (error ? error : EINTR); 583 } 584 if ((bp->b_flags & B_CACHE) == 0) { 585 bp->b_iocmd = BIO_READ; 586 vfs_busy_pages(bp, 0); 587 error = nfs_doio(vp, bp, cred, td); 588 if (error) { 589 brelse(bp); 590 } 591 while (error == NFSERR_BAD_COOKIE) { 592 (nmp->nm_rpcops->nr_invaldir)(vp); 593 error = nfs_vinvalbuf(vp, 0, td, 1); 594 /* 595 * Yuck! The directory has been modified on the 596 * server. The only way to get the block is by 597 * reading from the beginning to get all the 598 * offset cookies. 599 * 600 * Leave the last bp intact unless there is an error. 601 * Loop back up to the while if the error is another 602 * NFSERR_BAD_COOKIE (double yuch!). 603 */ 604 for (i = 0; i <= lbn && !error; i++) { 605 if (np->n_direofoffset 606 && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) 607 return (0); 608 bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, td); 609 if (!bp) { 610 error = nfs_sigintr(nmp, td); 611 return (error ? error : EINTR); 612 } 613 if ((bp->b_flags & B_CACHE) == 0) { 614 bp->b_iocmd = BIO_READ; 615 vfs_busy_pages(bp, 0); 616 error = nfs_doio(vp, bp, cred, td); 617 /* 618 * no error + B_INVAL == directory EOF, 619 * use the block. 620 */ 621 if (error == 0 && (bp->b_flags & B_INVAL)) 622 break; 623 } 624 /* 625 * An error will throw away the block and the 626 * for loop will break out. If no error and this 627 * is not the block we want, we throw away the 628 * block and go for the next one via the for loop. 629 */ 630 if (error || i < lbn) 631 brelse(bp); 632 } 633 } 634 /* 635 * The above while is repeated if we hit another cookie 636 * error. If we hit an error and it wasn't a cookie error, 637 * we give up. 638 */ 639 if (error) 640 return (error); 641 } 642 643 /* 644 * If not eof and read aheads are enabled, start one. 645 * (You need the current block first, so that you have the 646 * directory offset cookie of the next block.) 647 */ 648 if (nmp->nm_readahead > 0 && 649 (bp->b_flags & B_INVAL) == 0 && 650 (np->n_direofoffset == 0 || 651 (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && 652 incore(&vp->v_bufobj, lbn + 1) == NULL) { 653 rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td); 654 if (rabp) { 655 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 656 rabp->b_flags |= B_ASYNC; 657 rabp->b_iocmd = BIO_READ; 658 vfs_busy_pages(rabp, 0); 659 if (nfs_asyncio(nmp, rabp, cred, td)) { 660 rabp->b_flags |= B_INVAL; 661 rabp->b_ioflags |= BIO_ERROR; 662 vfs_unbusy_pages(rabp); 663 brelse(rabp); 664 } 665 } else { 666 brelse(rabp); 667 } 668 } 669 } 670 /* 671 * Unlike VREG files, whos buffer size ( bp->b_bcount ) is 672 * chopped for the EOF condition, we cannot tell how large 673 * NFS directories are going to be until we hit EOF. So 674 * an NFS directory buffer is *not* chopped to its EOF. Now, 675 * it just so happens that b_resid will effectively chop it 676 * to EOF. *BUT* this information is lost if the buffer goes 677 * away and is reconstituted into a B_CACHE state ( due to 678 * being VMIO ) later. So we keep track of the directory eof 679 * in np->n_direofoffset and chop it off as an extra step 680 * right here. 681 */ 682 n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); 683 if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset) 684 n = np->n_direofoffset - uio->uio_offset; 685 break; 686 default: 687 nfs_printf(" nfs_bioread: type %x unexpected\n", vp->v_type); 688 bp = NULL; 689 break; 690 }; 691 692 if (n > 0) { 693 error = uiomove(bp->b_data + on, (int)n, uio); 694 } 695 if (vp->v_type == VLNK) 696 n = 0; 697 if (bp != NULL) 698 brelse(bp); 699 } while (error == 0 && uio->uio_resid > 0 && n > 0); 700 return (error); 701} 702 703/* 704 * The NFS write path cannot handle iovecs with len > 1. So we need to 705 * break up iovecs accordingly (restricting them to wsize). 706 * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf). 707 * For the ASYNC case, 2 copies are needed. The first a copy from the 708 * user buffer to a staging buffer and then a second copy from the staging 709 * buffer to mbufs. This can be optimized by copying from the user buffer 710 * directly into mbufs and passing the chain down, but that requires a 711 * fair amount of re-working of the relevant codepaths (and can be done 712 * later). 713 */ 714static int 715nfs_directio_write(vp, uiop, cred, ioflag) 716 struct vnode *vp; 717 struct uio *uiop; 718 struct ucred *cred; 719 int ioflag; 720{ 721 int error; 722 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 723 struct thread *td = uiop->uio_td; 724 int size; 725 int wsize; 726 727 mtx_lock(&nmp->nm_mtx); 728 wsize = nmp->nm_wsize; 729 mtx_unlock(&nmp->nm_mtx); 730 if (ioflag & IO_SYNC) { 731 int iomode, must_commit; 732 struct uio uio; 733 struct iovec iov; 734do_sync: 735 while (uiop->uio_resid > 0) { 736 size = MIN(uiop->uio_resid, wsize); 737 size = MIN(uiop->uio_iov->iov_len, size); 738 iov.iov_base = uiop->uio_iov->iov_base; 739 iov.iov_len = size; 740 uio.uio_iov = &iov; 741 uio.uio_iovcnt = 1; 742 uio.uio_offset = uiop->uio_offset; 743 uio.uio_resid = size; 744 uio.uio_segflg = UIO_USERSPACE; 745 uio.uio_rw = UIO_WRITE; 746 uio.uio_td = td; 747 iomode = NFSV3WRITE_FILESYNC; 748 error = (nmp->nm_rpcops->nr_writerpc)(vp, &uio, cred, 749 &iomode, &must_commit); 750 KASSERT((must_commit == 0), 751 ("nfs_directio_write: Did not commit write")); 752 if (error) 753 return (error); 754 uiop->uio_offset += size; 755 uiop->uio_resid -= size; 756 if (uiop->uio_iov->iov_len <= size) { 757 uiop->uio_iovcnt--; 758 uiop->uio_iov++; 759 } else { 760 uiop->uio_iov->iov_base = 761 (char *)uiop->uio_iov->iov_base + size; 762 uiop->uio_iov->iov_len -= size; 763 } 764 } 765 } else { 766 struct uio *t_uio; 767 struct iovec *t_iov; 768 struct buf *bp; 769 770 /* 771 * Break up the write into blocksize chunks and hand these 772 * over to nfsiod's for write back. 773 * Unfortunately, this incurs a copy of the data. Since 774 * the user could modify the buffer before the write is 775 * initiated. 776 * 777 * The obvious optimization here is that one of the 2 copies 778 * in the async write path can be eliminated by copying the 779 * data here directly into mbufs and passing the mbuf chain 780 * down. But that will require a fair amount of re-working 781 * of the code and can be done if there's enough interest 782 * in NFS directio access. 783 */ 784 while (uiop->uio_resid > 0) { 785 size = MIN(uiop->uio_resid, wsize); 786 size = MIN(uiop->uio_iov->iov_len, size); 787 bp = getpbuf(&nfs_pbuf_freecnt); 788 t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); 789 t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); 790 t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); 791 t_iov->iov_len = size; 792 t_uio->uio_iov = t_iov; 793 t_uio->uio_iovcnt = 1; 794 t_uio->uio_offset = uiop->uio_offset; 795 t_uio->uio_resid = size; 796 t_uio->uio_segflg = UIO_SYSSPACE; 797 t_uio->uio_rw = UIO_WRITE; 798 t_uio->uio_td = td; 799 KASSERT(uiop->uio_segflg == UIO_USERSPACE || 800 uiop->uio_segflg == UIO_SYSSPACE, 801 ("nfs_directio_write: Bad uio_segflg")); 802 if (uiop->uio_segflg == UIO_USERSPACE) { 803 error = copyin(uiop->uio_iov->iov_base, 804 t_iov->iov_base, size); 805 if (error != 0) 806 goto err_free; 807 } else 808 /* 809 * UIO_SYSSPACE may never happen, but handle 810 * it just in case it does. 811 */ 812 bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, 813 size); 814 bp->b_flags |= B_DIRECT; 815 bp->b_iocmd = BIO_WRITE; 816 if (cred != NOCRED) { 817 crhold(cred); 818 bp->b_wcred = cred; 819 } else 820 bp->b_wcred = NOCRED; 821 bp->b_caller1 = (void *)t_uio; 822 bp->b_vp = vp; 823 error = nfs_asyncio(nmp, bp, NOCRED, td); 824err_free: 825 if (error) { 826 free(t_iov->iov_base, M_NFSDIRECTIO); 827 free(t_iov, M_NFSDIRECTIO); 828 free(t_uio, M_NFSDIRECTIO); 829 bp->b_vp = NULL; 830 relpbuf(bp, &nfs_pbuf_freecnt); 831 if (error == EINTR) 832 return (error); 833 goto do_sync; 834 } 835 uiop->uio_offset += size; 836 uiop->uio_resid -= size; 837 if (uiop->uio_iov->iov_len <= size) { 838 uiop->uio_iovcnt--; 839 uiop->uio_iov++; 840 } else { 841 uiop->uio_iov->iov_base = 842 (char *)uiop->uio_iov->iov_base + size; 843 uiop->uio_iov->iov_len -= size; 844 } 845 } 846 } 847 return (0); 848} 849 850/* 851 * Vnode op for write using bio 852 */ 853int 854nfs_write(struct vop_write_args *ap) 855{ 856 int biosize; 857 struct uio *uio = ap->a_uio; 858 struct thread *td = uio->uio_td; 859 struct vnode *vp = ap->a_vp; 860 struct nfsnode *np = VTONFS(vp); 861 struct ucred *cred = ap->a_cred; 862 int ioflag = ap->a_ioflag; 863 struct buf *bp; 864 struct vattr vattr; 865 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 866 daddr_t lbn; 867 off_t end; 868 int bcount; 869 int n, on, error = 0; 870 871 KASSERT(uio->uio_rw == UIO_WRITE, ("nfs_write mode")); 872 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 873 ("nfs_write proc")); 874 if (vp->v_type != VREG) 875 return (EIO); 876 mtx_lock(&np->n_mtx); 877 if (np->n_flag & NWRITEERR) { 878 np->n_flag &= ~NWRITEERR; 879 mtx_unlock(&np->n_mtx); 880 return (np->n_error); 881 } else 882 mtx_unlock(&np->n_mtx); 883 mtx_lock(&nmp->nm_mtx); 884 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 885 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 886 mtx_unlock(&nmp->nm_mtx); 887 (void)nfs_fsinfo(nmp, vp, cred, td); 888 } else 889 mtx_unlock(&nmp->nm_mtx); 890 891 /* 892 * Synchronously flush pending buffers if we are in synchronous 893 * mode or if we are appending. 894 */ 895 if (ioflag & (IO_APPEND | IO_SYNC)) { 896 mtx_lock(&np->n_mtx); 897 if (np->n_flag & NMODIFIED) { 898 mtx_unlock(&np->n_mtx); 899#ifdef notyet /* Needs matching nonblock semantics elsewhere, too. */ 900 /* 901 * Require non-blocking, synchronous writes to 902 * dirty files to inform the program it needs 903 * to fsync(2) explicitly. 904 */ 905 if (ioflag & IO_NDELAY) 906 return (EAGAIN); 907#endif 908flush_and_restart: 909 np->n_attrstamp = 0; 910 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 911 error = nfs_vinvalbuf(vp, V_SAVE, td, 1); 912 if (error) 913 return (error); 914 } else 915 mtx_unlock(&np->n_mtx); 916 } 917 918 /* 919 * If IO_APPEND then load uio_offset. We restart here if we cannot 920 * get the append lock. 921 */ 922 if (ioflag & IO_APPEND) { 923 np->n_attrstamp = 0; 924 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 925 error = VOP_GETATTR(vp, &vattr, cred); 926 if (error) 927 return (error); 928 mtx_lock(&np->n_mtx); 929 uio->uio_offset = np->n_size; 930 mtx_unlock(&np->n_mtx); 931 } 932 933 if (uio->uio_offset < 0) 934 return (EINVAL); 935 end = uio->uio_offset + uio->uio_resid; 936 if (end > nmp->nm_maxfilesize || end < uio->uio_offset) 937 return (EFBIG); 938 if (uio->uio_resid == 0) 939 return (0); 940 941 if (nfs_directio_enable && (ioflag & IO_DIRECT) && vp->v_type == VREG) 942 return nfs_directio_write(vp, uio, cred, ioflag); 943 944 /* 945 * Maybe this should be above the vnode op call, but so long as 946 * file servers have no limits, i don't think it matters 947 */ 948 if (vn_rlimit_fsize(vp, uio, td)) 949 return (EFBIG); 950 951 biosize = vp->v_bufobj.bo_bsize; 952 /* 953 * Find all of this file's B_NEEDCOMMIT buffers. If our writes 954 * would exceed the local maximum per-file write commit size when 955 * combined with those, we must decide whether to flush, 956 * go synchronous, or return error. We don't bother checking 957 * IO_UNIT -- we just make all writes atomic anyway, as there's 958 * no point optimizing for something that really won't ever happen. 959 */ 960 if (!(ioflag & IO_SYNC)) { 961 int nflag; 962 963 mtx_lock(&np->n_mtx); 964 nflag = np->n_flag; 965 mtx_unlock(&np->n_mtx); 966 int needrestart = 0; 967 if (nmp->nm_wcommitsize < uio->uio_resid) { 968 /* 969 * If this request could not possibly be completed 970 * without exceeding the maximum outstanding write 971 * commit size, see if we can convert it into a 972 * synchronous write operation. 973 */ 974 if (ioflag & IO_NDELAY) 975 return (EAGAIN); 976 ioflag |= IO_SYNC; 977 if (nflag & NMODIFIED) 978 needrestart = 1; 979 } else if (nflag & NMODIFIED) { 980 int wouldcommit = 0; 981 BO_LOCK(&vp->v_bufobj); 982 if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { 983 TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, 984 b_bobufs) { 985 if (bp->b_flags & B_NEEDCOMMIT) 986 wouldcommit += bp->b_bcount; 987 } 988 } 989 BO_UNLOCK(&vp->v_bufobj); 990 /* 991 * Since we're not operating synchronously and 992 * bypassing the buffer cache, we are in a commit 993 * and holding all of these buffers whether 994 * transmitted or not. If not limited, this 995 * will lead to the buffer cache deadlocking, 996 * as no one else can flush our uncommitted buffers. 997 */ 998 wouldcommit += uio->uio_resid; 999 /* 1000 * If we would initially exceed the maximum 1001 * outstanding write commit size, flush and restart. 1002 */ 1003 if (wouldcommit > nmp->nm_wcommitsize) 1004 needrestart = 1; 1005 } 1006 if (needrestart) 1007 goto flush_and_restart; 1008 } 1009 1010 do { 1011 nfsstats.biocache_writes++; 1012 lbn = uio->uio_offset / biosize; 1013 on = uio->uio_offset & (biosize-1); 1014 n = MIN((unsigned)(biosize - on), uio->uio_resid); 1015again: 1016 /* 1017 * Handle direct append and file extension cases, calculate 1018 * unaligned buffer size. 1019 */ 1020 mtx_lock(&np->n_mtx); 1021 if (uio->uio_offset == np->n_size && n) { 1022 mtx_unlock(&np->n_mtx); 1023 /* 1024 * Get the buffer (in its pre-append state to maintain 1025 * B_CACHE if it was previously set). Resize the 1026 * nfsnode after we have locked the buffer to prevent 1027 * readers from reading garbage. 1028 */ 1029 bcount = on; 1030 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1031 1032 if (bp != NULL) { 1033 long save; 1034 1035 mtx_lock(&np->n_mtx); 1036 np->n_size = uio->uio_offset + n; 1037 np->n_flag |= NMODIFIED; 1038 vnode_pager_setsize(vp, np->n_size); 1039 mtx_unlock(&np->n_mtx); 1040 1041 save = bp->b_flags & B_CACHE; 1042 bcount += n; 1043 allocbuf(bp, bcount); 1044 bp->b_flags |= save; 1045 } 1046 } else { 1047 /* 1048 * Obtain the locked cache block first, and then 1049 * adjust the file's size as appropriate. 1050 */ 1051 bcount = on + n; 1052 if ((off_t)lbn * biosize + bcount < np->n_size) { 1053 if ((off_t)(lbn + 1) * biosize < np->n_size) 1054 bcount = biosize; 1055 else 1056 bcount = np->n_size - (off_t)lbn * biosize; 1057 } 1058 mtx_unlock(&np->n_mtx); 1059 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1060 mtx_lock(&np->n_mtx); 1061 if (uio->uio_offset + n > np->n_size) { 1062 np->n_size = uio->uio_offset + n; 1063 np->n_flag |= NMODIFIED; 1064 vnode_pager_setsize(vp, np->n_size); 1065 } 1066 mtx_unlock(&np->n_mtx); 1067 } 1068 1069 if (!bp) { 1070 error = nfs_sigintr(nmp, td); 1071 if (!error) 1072 error = EINTR; 1073 break; 1074 } 1075 1076 /* 1077 * Issue a READ if B_CACHE is not set. In special-append 1078 * mode, B_CACHE is based on the buffer prior to the write 1079 * op and is typically set, avoiding the read. If a read 1080 * is required in special append mode, the server will 1081 * probably send us a short-read since we extended the file 1082 * on our end, resulting in b_resid == 0 and, thusly, 1083 * B_CACHE getting set. 1084 * 1085 * We can also avoid issuing the read if the write covers 1086 * the entire buffer. We have to make sure the buffer state 1087 * is reasonable in this case since we will not be initiating 1088 * I/O. See the comments in kern/vfs_bio.c's getblk() for 1089 * more information. 1090 * 1091 * B_CACHE may also be set due to the buffer being cached 1092 * normally. 1093 */ 1094 1095 if (on == 0 && n == bcount) { 1096 bp->b_flags |= B_CACHE; 1097 bp->b_flags &= ~B_INVAL; 1098 bp->b_ioflags &= ~BIO_ERROR; 1099 } 1100 1101 if ((bp->b_flags & B_CACHE) == 0) { 1102 bp->b_iocmd = BIO_READ; 1103 vfs_busy_pages(bp, 0); 1104 error = nfs_doio(vp, bp, cred, td); 1105 if (error) { 1106 brelse(bp); 1107 break; 1108 } 1109 } 1110 if (bp->b_wcred == NOCRED) 1111 bp->b_wcred = crhold(cred); 1112 mtx_lock(&np->n_mtx); 1113 np->n_flag |= NMODIFIED; 1114 mtx_unlock(&np->n_mtx); 1115 1116 /* 1117 * If dirtyend exceeds file size, chop it down. This should 1118 * not normally occur but there is an append race where it 1119 * might occur XXX, so we log it. 1120 * 1121 * If the chopping creates a reverse-indexed or degenerate 1122 * situation with dirtyoff/end, we 0 both of them. 1123 */ 1124 1125 if (bp->b_dirtyend > bcount) { 1126 nfs_printf("NFS append race @%lx:%d\n", 1127 (long)bp->b_blkno * DEV_BSIZE, 1128 bp->b_dirtyend - bcount); 1129 bp->b_dirtyend = bcount; 1130 } 1131 1132 if (bp->b_dirtyoff >= bp->b_dirtyend) 1133 bp->b_dirtyoff = bp->b_dirtyend = 0; 1134 1135 /* 1136 * If the new write will leave a contiguous dirty 1137 * area, just update the b_dirtyoff and b_dirtyend, 1138 * otherwise force a write rpc of the old dirty area. 1139 * 1140 * While it is possible to merge discontiguous writes due to 1141 * our having a B_CACHE buffer ( and thus valid read data 1142 * for the hole), we don't because it could lead to 1143 * significant cache coherency problems with multiple clients, 1144 * especially if locking is implemented later on. 1145 * 1146 * as an optimization we could theoretically maintain 1147 * a linked list of discontinuous areas, but we would still 1148 * have to commit them separately so there isn't much 1149 * advantage to it except perhaps a bit of asynchronization. 1150 */ 1151 1152 if (bp->b_dirtyend > 0 && 1153 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 1154 if (bwrite(bp) == EINTR) { 1155 error = EINTR; 1156 break; 1157 } 1158 goto again; 1159 } 1160 1161 error = uiomove((char *)bp->b_data + on, n, uio); 1162 1163 /* 1164 * Since this block is being modified, it must be written 1165 * again and not just committed. Since write clustering does 1166 * not work for the stage 1 data write, only the stage 2 1167 * commit rpc, we have to clear B_CLUSTEROK as well. 1168 */ 1169 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1170 1171 if (error) { 1172 bp->b_ioflags |= BIO_ERROR; 1173 brelse(bp); 1174 break; 1175 } 1176 1177 /* 1178 * Only update dirtyoff/dirtyend if not a degenerate 1179 * condition. 1180 */ 1181 if (n) { 1182 if (bp->b_dirtyend > 0) { 1183 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 1184 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 1185 } else { 1186 bp->b_dirtyoff = on; 1187 bp->b_dirtyend = on + n; 1188 } 1189 vfs_bio_set_valid(bp, on, n); 1190 } 1191 1192 /* 1193 * If IO_SYNC do bwrite(). 1194 * 1195 * IO_INVAL appears to be unused. The idea appears to be 1196 * to turn off caching in this case. Very odd. XXX 1197 */ 1198 if ((ioflag & IO_SYNC)) { 1199 if (ioflag & IO_INVAL) 1200 bp->b_flags |= B_NOCACHE; 1201 error = bwrite(bp); 1202 if (error) 1203 break; 1204 } else if ((n + on) == biosize) { 1205 bp->b_flags |= B_ASYNC; 1206 (void) (nmp->nm_rpcops->nr_writebp)(bp, 0, NULL); 1207 } else { 1208 bdwrite(bp); 1209 } 1210 } while (uio->uio_resid > 0 && n > 0); 1211 1212 return (error); 1213} 1214 1215/* 1216 * Get an nfs cache block. 1217 * 1218 * Allocate a new one if the block isn't currently in the cache 1219 * and return the block marked busy. If the calling process is 1220 * interrupted by a signal for an interruptible mount point, return 1221 * NULL. 1222 * 1223 * The caller must carefully deal with the possible B_INVAL state of 1224 * the buffer. nfs_doio() clears B_INVAL (and nfs_asyncio() clears it 1225 * indirectly), so synchronous reads can be issued without worrying about 1226 * the B_INVAL state. We have to be a little more careful when dealing 1227 * with writes (see comments in nfs_write()) when extending a file past 1228 * its EOF. 1229 */ 1230static struct buf * 1231nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td) 1232{ 1233 struct buf *bp; 1234 struct mount *mp; 1235 struct nfsmount *nmp; 1236 1237 mp = vp->v_mount; 1238 nmp = VFSTONFS(mp); 1239 1240 if (nmp->nm_flag & NFSMNT_INT) { 1241 sigset_t oldset; 1242 1243 nfs_set_sigmask(td, &oldset); 1244 bp = getblk(vp, bn, size, NFS_PCATCH, 0, 0); 1245 nfs_restore_sigmask(td, &oldset); 1246 while (bp == NULL) { 1247 if (nfs_sigintr(nmp, td)) 1248 return (NULL); 1249 bp = getblk(vp, bn, size, 0, 2 * hz, 0); 1250 } 1251 } else { 1252 bp = getblk(vp, bn, size, 0, 0, 0); 1253 } 1254 1255 if (vp->v_type == VREG) 1256 bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / DEV_BSIZE); 1257 return (bp); 1258} 1259 1260/* 1261 * Flush and invalidate all dirty buffers. If another process is already 1262 * doing the flush, just wait for completion. 1263 */ 1264int 1265nfs_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg) 1266{ 1267 struct nfsnode *np = VTONFS(vp); 1268 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1269 int error = 0, slpflag, slptimeo; 1270 int old_lock = 0; 1271 1272 ASSERT_VOP_LOCKED(vp, "nfs_vinvalbuf"); 1273 1274 if ((nmp->nm_flag & NFSMNT_INT) == 0) 1275 intrflg = 0; 1276 if (intrflg) { 1277 slpflag = NFS_PCATCH; 1278 slptimeo = 2 * hz; 1279 } else { 1280 slpflag = 0; 1281 slptimeo = 0; 1282 } 1283 1284 old_lock = nfs_upgrade_vnlock(vp); 1285 if (vp->v_iflag & VI_DOOMED) { 1286 /* 1287 * Since vgonel() uses the generic vinvalbuf() to flush 1288 * dirty buffers and it does not call this function, it 1289 * is safe to just return OK when VI_DOOMED is set. 1290 */ 1291 nfs_downgrade_vnlock(vp, old_lock); 1292 return (0); 1293 } 1294 1295 /* 1296 * Now, flush as required. 1297 */ 1298 if ((flags & V_SAVE) && (vp->v_bufobj.bo_object != NULL)) { 1299 VM_OBJECT_LOCK(vp->v_bufobj.bo_object); 1300 vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); 1301 VM_OBJECT_UNLOCK(vp->v_bufobj.bo_object); 1302 /* 1303 * If the page clean was interrupted, fail the invalidation. 1304 * Not doing so, we run the risk of losing dirty pages in the 1305 * vinvalbuf() call below. 1306 */ 1307 if (intrflg && (error = nfs_sigintr(nmp, td))) 1308 goto out; 1309 } 1310 1311 error = vinvalbuf(vp, flags, slpflag, 0); 1312 while (error) { 1313 if (intrflg && (error = nfs_sigintr(nmp, td))) 1314 goto out; 1315 error = vinvalbuf(vp, flags, 0, slptimeo); 1316 } 1317 mtx_lock(&np->n_mtx); 1318 if (np->n_directio_asyncwr == 0) 1319 np->n_flag &= ~NMODIFIED; 1320 mtx_unlock(&np->n_mtx); 1321out: 1322 nfs_downgrade_vnlock(vp, old_lock); 1323 return error; 1324} 1325 1326/* 1327 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 1328 * This is mainly to avoid queueing async I/O requests when the nfsiods 1329 * are all hung on a dead server. 1330 * 1331 * Note: nfs_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp 1332 * is eventually dequeued by the async daemon, nfs_doio() *will*. 1333 */ 1334int 1335nfs_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) 1336{ 1337 int iod; 1338 int gotiod; 1339 int slpflag = 0; 1340 int slptimeo = 0; 1341 int error, error2; 1342 1343 /* 1344 * Commits are usually short and sweet so lets save some cpu and 1345 * leave the async daemons for more important rpc's (such as reads 1346 * and writes). 1347 * 1348 * Readdirplus RPCs do vget()s to acquire the vnodes for entries 1349 * in the directory in order to update attributes. This can deadlock 1350 * with another thread that is waiting for async I/O to be done by 1351 * an nfsiod thread while holding a lock on one of these vnodes. 1352 * To avoid this deadlock, don't allow the async nfsiod threads to 1353 * perform Readdirplus RPCs. 1354 */ 1355 mtx_lock(&nfs_iod_mtx); 1356 if ((bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && 1357 (nmp->nm_bufqiods > nfs_numasync / 2)) || 1358 (bp->b_vp->v_type == VDIR && (nmp->nm_flag & NFSMNT_RDIRPLUS))) { 1359 mtx_unlock(&nfs_iod_mtx); 1360 return(EIO); 1361 } 1362again: 1363 if (nmp->nm_flag & NFSMNT_INT) 1364 slpflag = NFS_PCATCH; 1365 gotiod = FALSE; 1366 1367 /* 1368 * Find a free iod to process this request. 1369 */ 1370 for (iod = 0; iod < nfs_numasync; iod++) 1371 if (nfs_iodwant[iod] == NFSIOD_AVAILABLE) { 1372 gotiod = TRUE; 1373 break; 1374 } 1375 1376 /* 1377 * Try to create one if none are free. 1378 */ 1379 if (!gotiod) 1380 nfs_nfsiodnew(); 1381 else { 1382 /* 1383 * Found one, so wake it up and tell it which 1384 * mount to process. 1385 */ 1386 NFS_DPF(ASYNCIO, ("nfs_asyncio: waking iod %d for mount %p\n", 1387 iod, nmp)); 1388 nfs_iodwant[iod] = NFSIOD_NOT_AVAILABLE; 1389 nfs_iodmount[iod] = nmp; 1390 nmp->nm_bufqiods++; 1391 wakeup(&nfs_iodwant[iod]); 1392 } 1393 1394 /* 1395 * If none are free, we may already have an iod working on this mount 1396 * point. If so, it will process our request. 1397 */ 1398 if (!gotiod) { 1399 if (nmp->nm_bufqiods > 0) { 1400 NFS_DPF(ASYNCIO, 1401 ("nfs_asyncio: %d iods are already processing mount %p\n", 1402 nmp->nm_bufqiods, nmp)); 1403 gotiod = TRUE; 1404 } 1405 } 1406 1407 /* 1408 * If we have an iod which can process the request, then queue 1409 * the buffer. 1410 */ 1411 if (gotiod) { 1412 /* 1413 * Ensure that the queue never grows too large. We still want 1414 * to asynchronize so we block rather then return EIO. 1415 */ 1416 while (nmp->nm_bufqlen >= 2 * nfs_numasync) { 1417 NFS_DPF(ASYNCIO, 1418 ("nfs_asyncio: waiting for mount %p queue to drain\n", nmp)); 1419 nmp->nm_bufqwant = TRUE; 1420 error = nfs_msleep(td, &nmp->nm_bufq, &nfs_iod_mtx, 1421 slpflag | PRIBIO, 1422 "nfsaio", slptimeo); 1423 if (error) { 1424 error2 = nfs_sigintr(nmp, td); 1425 if (error2) { 1426 mtx_unlock(&nfs_iod_mtx); 1427 return (error2); 1428 } 1429 if (slpflag == NFS_PCATCH) { 1430 slpflag = 0; 1431 slptimeo = 2 * hz; 1432 } 1433 } 1434 /* 1435 * We might have lost our iod while sleeping, 1436 * so check and loop if nescessary. 1437 */ 1438 goto again; 1439 } 1440 1441 /* We might have lost our nfsiod */ 1442 if (nmp->nm_bufqiods == 0) { 1443 NFS_DPF(ASYNCIO, 1444("nfs_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1445 goto again; 1446 } 1447 1448 if (bp->b_iocmd == BIO_READ) { 1449 if (bp->b_rcred == NOCRED && cred != NOCRED) 1450 bp->b_rcred = crhold(cred); 1451 } else { 1452 if (bp->b_wcred == NOCRED && cred != NOCRED) 1453 bp->b_wcred = crhold(cred); 1454 } 1455 1456 if (bp->b_flags & B_REMFREE) 1457 bremfreef(bp); 1458 BUF_KERNPROC(bp); 1459 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 1460 nmp->nm_bufqlen++; 1461 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1462 mtx_lock(&(VTONFS(bp->b_vp))->n_mtx); 1463 VTONFS(bp->b_vp)->n_flag |= NMODIFIED; 1464 VTONFS(bp->b_vp)->n_directio_asyncwr++; 1465 mtx_unlock(&(VTONFS(bp->b_vp))->n_mtx); 1466 } 1467 mtx_unlock(&nfs_iod_mtx); 1468 return (0); 1469 } 1470 1471 mtx_unlock(&nfs_iod_mtx); 1472 1473 /* 1474 * All the iods are busy on other mounts, so return EIO to 1475 * force the caller to process the i/o synchronously. 1476 */ 1477 NFS_DPF(ASYNCIO, ("nfs_asyncio: no iods available, i/o is synchronous\n")); 1478 return (EIO); 1479} 1480 1481void 1482nfs_doio_directwrite(struct buf *bp) 1483{ 1484 int iomode, must_commit; 1485 struct uio *uiop = (struct uio *)bp->b_caller1; 1486 char *iov_base = uiop->uio_iov->iov_base; 1487 struct nfsmount *nmp = VFSTONFS(bp->b_vp->v_mount); 1488 1489 iomode = NFSV3WRITE_FILESYNC; 1490 uiop->uio_td = NULL; /* NULL since we're in nfsiod */ 1491 (nmp->nm_rpcops->nr_writerpc)(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit); 1492 KASSERT((must_commit == 0), ("nfs_doio_directwrite: Did not commit write")); 1493 free(iov_base, M_NFSDIRECTIO); 1494 free(uiop->uio_iov, M_NFSDIRECTIO); 1495 free(uiop, M_NFSDIRECTIO); 1496 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1497 struct nfsnode *np = VTONFS(bp->b_vp); 1498 mtx_lock(&np->n_mtx); 1499 np->n_directio_asyncwr--; 1500 if (np->n_directio_asyncwr == 0) { 1501 VTONFS(bp->b_vp)->n_flag &= ~NMODIFIED; 1502 if ((np->n_flag & NFSYNCWAIT)) { 1503 np->n_flag &= ~NFSYNCWAIT; 1504 wakeup((caddr_t)&np->n_directio_asyncwr); 1505 } 1506 } 1507 mtx_unlock(&np->n_mtx); 1508 } 1509 bp->b_vp = NULL; 1510 relpbuf(bp, &nfs_pbuf_freecnt); 1511} 1512 1513/* 1514 * Do an I/O operation to/from a cache block. This may be called 1515 * synchronously or from an nfsiod. 1516 */ 1517int 1518nfs_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td) 1519{ 1520 struct uio *uiop; 1521 struct nfsnode *np; 1522 struct nfsmount *nmp; 1523 int error = 0, iomode, must_commit = 0; 1524 struct uio uio; 1525 struct iovec io; 1526 struct proc *p = td ? td->td_proc : NULL; 1527 uint8_t iocmd; 1528 1529 np = VTONFS(vp); 1530 nmp = VFSTONFS(vp->v_mount); 1531 uiop = &uio; 1532 uiop->uio_iov = &io; 1533 uiop->uio_iovcnt = 1; 1534 uiop->uio_segflg = UIO_SYSSPACE; 1535 uiop->uio_td = td; 1536 1537 /* 1538 * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We 1539 * do this here so we do not have to do it in all the code that 1540 * calls us. 1541 */ 1542 bp->b_flags &= ~B_INVAL; 1543 bp->b_ioflags &= ~BIO_ERROR; 1544 1545 KASSERT(!(bp->b_flags & B_DONE), ("nfs_doio: bp %p already marked done", bp)); 1546 iocmd = bp->b_iocmd; 1547 if (iocmd == BIO_READ) { 1548 io.iov_len = uiop->uio_resid = bp->b_bcount; 1549 io.iov_base = bp->b_data; 1550 uiop->uio_rw = UIO_READ; 1551 1552 switch (vp->v_type) { 1553 case VREG: 1554 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1555 nfsstats.read_bios++; 1556 error = (nmp->nm_rpcops->nr_readrpc)(vp, uiop, cr); 1557 1558 if (!error) { 1559 if (uiop->uio_resid) { 1560 /* 1561 * If we had a short read with no error, we must have 1562 * hit a file hole. We should zero-fill the remainder. 1563 * This can also occur if the server hits the file EOF. 1564 * 1565 * Holes used to be able to occur due to pending 1566 * writes, but that is not possible any longer. 1567 */ 1568 int nread = bp->b_bcount - uiop->uio_resid; 1569 int left = uiop->uio_resid; 1570 1571 if (left > 0) 1572 bzero((char *)bp->b_data + nread, left); 1573 uiop->uio_resid = 0; 1574 } 1575 } 1576 /* ASSERT_VOP_LOCKED(vp, "nfs_doio"); */ 1577 if (p && (vp->v_vflag & VV_TEXT)) { 1578 mtx_lock(&np->n_mtx); 1579 if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.va_mtime)) { 1580 mtx_unlock(&np->n_mtx); 1581 PROC_LOCK(p); 1582 killproc(p, "text file modification"); 1583 PROC_UNLOCK(p); 1584 } else 1585 mtx_unlock(&np->n_mtx); 1586 } 1587 break; 1588 case VLNK: 1589 uiop->uio_offset = (off_t)0; 1590 nfsstats.readlink_bios++; 1591 error = (nmp->nm_rpcops->nr_readlinkrpc)(vp, uiop, cr); 1592 break; 1593 case VDIR: 1594 nfsstats.readdir_bios++; 1595 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; 1596 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) { 1597 error = nfs_readdirplusrpc(vp, uiop, cr); 1598 if (error == NFSERR_NOTSUPP) 1599 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1600 } 1601 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1602 error = nfs_readdirrpc(vp, uiop, cr); 1603 /* 1604 * end-of-directory sets B_INVAL but does not generate an 1605 * error. 1606 */ 1607 if (error == 0 && uiop->uio_resid == bp->b_bcount) 1608 bp->b_flags |= B_INVAL; 1609 break; 1610 default: 1611 nfs_printf("nfs_doio: type %x unexpected\n", vp->v_type); 1612 break; 1613 }; 1614 if (error) { 1615 bp->b_ioflags |= BIO_ERROR; 1616 bp->b_error = error; 1617 } 1618 } else { 1619 /* 1620 * If we only need to commit, try to commit 1621 */ 1622 if (bp->b_flags & B_NEEDCOMMIT) { 1623 int retv; 1624 off_t off; 1625 1626 off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff; 1627 retv = (nmp->nm_rpcops->nr_commit)( 1628 vp, off, bp->b_dirtyend-bp->b_dirtyoff, 1629 bp->b_wcred, td); 1630 if (retv == 0) { 1631 bp->b_dirtyoff = bp->b_dirtyend = 0; 1632 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1633 bp->b_resid = 0; 1634 bufdone(bp); 1635 return (0); 1636 } 1637 if (retv == NFSERR_STALEWRITEVERF) { 1638 nfs_clearcommit(vp->v_mount); 1639 } 1640 } 1641 1642 /* 1643 * Setup for actual write 1644 */ 1645 mtx_lock(&np->n_mtx); 1646 if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size) 1647 bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE; 1648 mtx_unlock(&np->n_mtx); 1649 1650 if (bp->b_dirtyend > bp->b_dirtyoff) { 1651 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1652 - bp->b_dirtyoff; 1653 uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE 1654 + bp->b_dirtyoff; 1655 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1656 uiop->uio_rw = UIO_WRITE; 1657 nfsstats.write_bios++; 1658 1659 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) 1660 iomode = NFSV3WRITE_UNSTABLE; 1661 else 1662 iomode = NFSV3WRITE_FILESYNC; 1663 1664 error = (nmp->nm_rpcops->nr_writerpc)(vp, uiop, cr, &iomode, &must_commit); 1665 1666 /* 1667 * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try 1668 * to cluster the buffers needing commit. This will allow 1669 * the system to submit a single commit rpc for the whole 1670 * cluster. We can do this even if the buffer is not 100% 1671 * dirty (relative to the NFS blocksize), so we optimize the 1672 * append-to-file-case. 1673 * 1674 * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be 1675 * cleared because write clustering only works for commit 1676 * rpc's, not for the data portion of the write). 1677 */ 1678 1679 if (!error && iomode == NFSV3WRITE_UNSTABLE) { 1680 bp->b_flags |= B_NEEDCOMMIT; 1681 if (bp->b_dirtyoff == 0 1682 && bp->b_dirtyend == bp->b_bcount) 1683 bp->b_flags |= B_CLUSTEROK; 1684 } else { 1685 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1686 } 1687 1688 /* 1689 * For an interrupted write, the buffer is still valid 1690 * and the write hasn't been pushed to the server yet, 1691 * so we can't set BIO_ERROR and report the interruption 1692 * by setting B_EINTR. For the B_ASYNC case, B_EINTR 1693 * is not relevant, so the rpc attempt is essentially 1694 * a noop. For the case of a V3 write rpc not being 1695 * committed to stable storage, the block is still 1696 * dirty and requires either a commit rpc or another 1697 * write rpc with iomode == NFSV3WRITE_FILESYNC before 1698 * the block is reused. This is indicated by setting 1699 * the B_DELWRI and B_NEEDCOMMIT flags. 1700 * 1701 * If the buffer is marked B_PAGING, it does not reside on 1702 * the vp's paging queues so we cannot call bdirty(). The 1703 * bp in this case is not an NFS cache block so we should 1704 * be safe. XXX 1705 * 1706 * The logic below breaks up errors into recoverable and 1707 * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE 1708 * and keep the buffer around for potential write retries. 1709 * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) 1710 * and save the error in the nfsnode. This is less than ideal 1711 * but necessary. Keeping such buffers around could potentially 1712 * cause buffer exhaustion eventually (they can never be written 1713 * out, so will get constantly be re-dirtied). It also causes 1714 * all sorts of vfs panics. For non-recoverable write errors, 1715 * also invalidate the attrcache, so we'll be forced to go over 1716 * the wire for this object, returning an error to user on next 1717 * call (most of the time). 1718 */ 1719 if (error == EINTR || error == EIO || error == ETIMEDOUT 1720 || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1721 int s; 1722 1723 s = splbio(); 1724 bp->b_flags &= ~(B_INVAL|B_NOCACHE); 1725 if ((bp->b_flags & B_PAGING) == 0) { 1726 bdirty(bp); 1727 bp->b_flags &= ~B_DONE; 1728 } 1729 if (error && (bp->b_flags & B_ASYNC) == 0) 1730 bp->b_flags |= B_EINTR; 1731 splx(s); 1732 } else { 1733 if (error) { 1734 bp->b_ioflags |= BIO_ERROR; 1735 bp->b_flags |= B_INVAL; 1736 bp->b_error = np->n_error = error; 1737 mtx_lock(&np->n_mtx); 1738 np->n_flag |= NWRITEERR; 1739 np->n_attrstamp = 0; 1740 KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); 1741 mtx_unlock(&np->n_mtx); 1742 } 1743 bp->b_dirtyoff = bp->b_dirtyend = 0; 1744 } 1745 } else { 1746 bp->b_resid = 0; 1747 bufdone(bp); 1748 return (0); 1749 } 1750 } 1751 bp->b_resid = uiop->uio_resid; 1752 if (must_commit) 1753 nfs_clearcommit(vp->v_mount); 1754 bufdone(bp); 1755 return (error); 1756} 1757 1758/* 1759 * Used to aid in handling ftruncate() operations on the NFS client side. 1760 * Truncation creates a number of special problems for NFS. We have to 1761 * throw away VM pages and buffer cache buffers that are beyond EOF, and 1762 * we have to properly handle VM pages or (potentially dirty) buffers 1763 * that straddle the truncation point. 1764 */ 1765 1766int 1767nfs_meta_setsize(struct vnode *vp, struct ucred *cred, struct thread *td, u_quad_t nsize) 1768{ 1769 struct nfsnode *np = VTONFS(vp); 1770 u_quad_t tsize; 1771 int biosize = vp->v_bufobj.bo_bsize; 1772 int error = 0; 1773 1774 mtx_lock(&np->n_mtx); 1775 tsize = np->n_size; 1776 np->n_size = nsize; 1777 mtx_unlock(&np->n_mtx); 1778 1779 if (nsize < tsize) { 1780 struct buf *bp; 1781 daddr_t lbn; 1782 int bufsize; 1783 1784 /* 1785 * vtruncbuf() doesn't get the buffer overlapping the 1786 * truncation point. We may have a B_DELWRI and/or B_CACHE 1787 * buffer that now needs to be truncated. 1788 */ 1789 error = vtruncbuf(vp, cred, td, nsize, biosize); 1790 lbn = nsize / biosize; 1791 bufsize = nsize & (biosize - 1); 1792 bp = nfs_getcacheblk(vp, lbn, bufsize, td); 1793 if (!bp) 1794 return EINTR; 1795 if (bp->b_dirtyoff > bp->b_bcount) 1796 bp->b_dirtyoff = bp->b_bcount; 1797 if (bp->b_dirtyend > bp->b_bcount) 1798 bp->b_dirtyend = bp->b_bcount; 1799 bp->b_flags |= B_RELBUF; /* don't leave garbage around */ 1800 brelse(bp); 1801 } else { 1802 vnode_pager_setsize(vp, nsize); 1803 } 1804 return(error); 1805} 1806 1807