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sys/fs/nfsclient/nfs_clbio.c
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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: releng/8.2/sys/fs/nfsclient/nfs_clbio.c 212836 2010-09-19 02:07:30Z rmacklem $"); 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/bio.h> 41 #include <sys/buf.h> 42 #include <sys/kernel.h> 43 #include <sys/mount.h> 44 #include <sys/proc.h> 45 #include <sys/resourcevar.h> 46 #include <sys/signalvar.h> 47 #include <sys/vmmeter.h> 48 #include <sys/vnode.h> 49 50 #include <vm/vm.h> 51 #include <vm/vm_extern.h> 52 #include <vm/vm_page.h> 53 #include <vm/vm_object.h> 54 #include <vm/vm_pager.h> 55 #include <vm/vnode_pager.h> 56 57 #include <fs/nfs/nfsport.h> 58 #include <fs/nfsclient/nfsmount.h> 59 #include <fs/nfsclient/nfs.h> 60 #include <fs/nfsclient/nfsnode.h> 61 62 extern int newnfs_directio_allow_mmap; 63 extern struct nfsstats newnfsstats; 64 extern struct mtx ncl_iod_mutex; 65 extern int ncl_numasync; 66 extern enum nfsiod_state ncl_iodwant[NFS_MAXRAHEAD]; 67 extern struct nfsmount *ncl_iodmount[NFS_MAXRAHEAD]; 68 extern int newnfs_directio_enable; 69 70 int ncl_pbuf_freecnt = -1; /* start out unlimited */ 71 72 static struct buf *nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, 73 struct thread *td); 74 static int nfs_directio_write(struct vnode *vp, struct uio *uiop, 75 struct ucred *cred, int ioflag); 76 77 /* 78 * Vnode op for VM getpages. 79 */ 80 int 81 ncl_getpages(struct vop_getpages_args *ap) 82 { 83 int i, error, nextoff, size, toff, count, npages; 84 struct uio uio; 85 struct iovec iov; 86 vm_offset_t kva; 87 struct buf *bp; 88 struct vnode *vp; 89 struct thread *td; 90 struct ucred *cred; 91 struct nfsmount *nmp; 92 vm_object_t object; 93 vm_page_t *pages; 94 struct nfsnode *np; 95 96 vp = ap->a_vp; 97 np = VTONFS(vp); 98 td = curthread; /* XXX */ 99 cred = curthread->td_ucred; /* XXX */ 100 nmp = VFSTONFS(vp->v_mount); 101 pages = ap->a_m; 102 count = ap->a_count; 103 104 if ((object = vp->v_object) == NULL) { 105 ncl_printf("nfs_getpages: called with non-merged cache vnode??\n"); 106 return (VM_PAGER_ERROR); 107 } 108 109 if (newnfs_directio_enable && !newnfs_directio_allow_mmap) { 110 mtx_lock(&np->n_mtx); 111 if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 112 mtx_unlock(&np->n_mtx); 113 ncl_printf("nfs_getpages: called on non-cacheable vnode??\n"); 114 return (VM_PAGER_ERROR); 115 } else 116 mtx_unlock(&np->n_mtx); 117 } 118 119 mtx_lock(&nmp->nm_mtx); 120 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 121 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 122 mtx_unlock(&nmp->nm_mtx); 123 /* We'll never get here for v4, because we always have fsinfo */ 124 (void)ncl_fsinfo(nmp, vp, cred, td); 125 } else 126 mtx_unlock(&nmp->nm_mtx); 127 128 npages = btoc(count); 129 130 /* 131 * If the requested page is partially valid, just return it and 132 * allow the pager to zero-out the blanks. Partially valid pages 133 * can only occur at the file EOF. 134 */ 135 VM_OBJECT_LOCK(object); 136 if (pages[ap->a_reqpage]->valid != 0) { 137 vm_page_lock_queues(); 138 for (i = 0; i < npages; ++i) { 139 if (i != ap->a_reqpage) 140 vm_page_free(pages[i]); 141 } 142 vm_page_unlock_queues(); 143 VM_OBJECT_UNLOCK(object); 144 return (0); 145 } 146 VM_OBJECT_UNLOCK(object); 147 148 /* 149 * We use only the kva address for the buffer, but this is extremely 150 * convienient and fast. 151 */ 152 bp = getpbuf(&ncl_pbuf_freecnt); 153 154 kva = (vm_offset_t) bp->b_data; 155 pmap_qenter(kva, pages, npages); 156 PCPU_INC(cnt.v_vnodein); 157 PCPU_ADD(cnt.v_vnodepgsin, npages); 158 159 iov.iov_base = (caddr_t) kva; 160 iov.iov_len = count; 161 uio.uio_iov = &iov; 162 uio.uio_iovcnt = 1; 163 uio.uio_offset = IDX_TO_OFF(pages[0]->pindex); 164 uio.uio_resid = count; 165 uio.uio_segflg = UIO_SYSSPACE; 166 uio.uio_rw = UIO_READ; 167 uio.uio_td = td; 168 169 error = ncl_readrpc(vp, &uio, cred); 170 pmap_qremove(kva, npages); 171 172 relpbuf(bp, &ncl_pbuf_freecnt); 173 174 if (error && (uio.uio_resid == count)) { 175 ncl_printf("nfs_getpages: error %d\n", error); 176 VM_OBJECT_LOCK(object); 177 vm_page_lock_queues(); 178 for (i = 0; i < npages; ++i) { 179 if (i != ap->a_reqpage) 180 vm_page_free(pages[i]); 181 } 182 vm_page_unlock_queues(); 183 VM_OBJECT_UNLOCK(object); 184 return (VM_PAGER_ERROR); 185 } 186 187 /* 188 * Calculate the number of bytes read and validate only that number 189 * of bytes. Note that due to pending writes, size may be 0. This 190 * does not mean that the remaining data is invalid! 191 */ 192 193 size = count - uio.uio_resid; 194 VM_OBJECT_LOCK(object); 195 vm_page_lock_queues(); 196 for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { 197 vm_page_t m; 198 nextoff = toff + PAGE_SIZE; 199 m = pages[i]; 200 201 if (nextoff <= size) { 202 /* 203 * Read operation filled an entire page 204 */ 205 m->valid = VM_PAGE_BITS_ALL; 206 KASSERT(m->dirty == 0, 207 ("nfs_getpages: page %p is dirty", m)); 208 } else if (size > toff) { 209 /* 210 * Read operation filled a partial page. 211 */ 212 m->valid = 0; 213 vm_page_set_valid(m, 0, size - toff); 214 KASSERT(m->dirty == 0, 215 ("nfs_getpages: page %p is dirty", m)); 216 } else { 217 /* 218 * Read operation was short. If no error occured 219 * we may have hit a zero-fill section. We simply 220 * leave valid set to 0. 221 */ 222 ; 223 } 224 if (i != ap->a_reqpage) { 225 /* 226 * Whether or not to leave the page activated is up in 227 * the air, but we should put the page on a page queue 228 * somewhere (it already is in the object). Result: 229 * It appears that emperical results show that 230 * deactivating pages is best. 231 */ 232 233 /* 234 * Just in case someone was asking for this page we 235 * now tell them that it is ok to use. 236 */ 237 if (!error) { 238 if (m->oflags & VPO_WANTED) 239 vm_page_activate(m); 240 else 241 vm_page_deactivate(m); 242 vm_page_wakeup(m); 243 } else { 244 vm_page_free(m); 245 } 246 } 247 } 248 vm_page_unlock_queues(); 249 VM_OBJECT_UNLOCK(object); 250 return (0); 251 } 252 253 /* 254 * Vnode op for VM putpages. 255 */ 256 int 257 ncl_putpages(struct vop_putpages_args *ap) 258 { 259 struct uio uio; 260 struct iovec iov; 261 vm_offset_t kva; 262 struct buf *bp; 263 int iomode, must_commit, i, error, npages, count; 264 off_t offset; 265 int *rtvals; 266 struct vnode *vp; 267 struct thread *td; 268 struct ucred *cred; 269 struct nfsmount *nmp; 270 struct nfsnode *np; 271 vm_page_t *pages; 272 273 vp = ap->a_vp; 274 np = VTONFS(vp); 275 td = curthread; /* XXX */ 276 cred = curthread->td_ucred; /* XXX */ 277 nmp = VFSTONFS(vp->v_mount); 278 pages = ap->a_m; 279 count = ap->a_count; 280 rtvals = ap->a_rtvals; 281 npages = btoc(count); 282 offset = IDX_TO_OFF(pages[0]->pindex); 283 284 mtx_lock(&nmp->nm_mtx); 285 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 286 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 287 mtx_unlock(&nmp->nm_mtx); 288 (void)ncl_fsinfo(nmp, vp, cred, td); 289 } else 290 mtx_unlock(&nmp->nm_mtx); 291 292 mtx_lock(&np->n_mtx); 293 if (newnfs_directio_enable && !newnfs_directio_allow_mmap && 294 (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 295 mtx_unlock(&np->n_mtx); 296 ncl_printf("ncl_putpages: called on noncache-able vnode??\n"); 297 mtx_lock(&np->n_mtx); 298 } 299 300 for (i = 0; i < npages; i++) 301 rtvals[i] = VM_PAGER_AGAIN; 302 303 /* 304 * When putting pages, do not extend file past EOF. 305 */ 306 if (offset + count > np->n_size) { 307 count = np->n_size - offset; 308 if (count < 0) 309 count = 0; 310 } 311 mtx_unlock(&np->n_mtx); 312 313 /* 314 * We use only the kva address for the buffer, but this is extremely 315 * convienient and fast. 316 */ 317 bp = getpbuf(&ncl_pbuf_freecnt); 318 319 kva = (vm_offset_t) bp->b_data; 320 pmap_qenter(kva, pages, npages); 321 PCPU_INC(cnt.v_vnodeout); 322 PCPU_ADD(cnt.v_vnodepgsout, count); 323 324 iov.iov_base = (caddr_t) kva; 325 iov.iov_len = count; 326 uio.uio_iov = &iov; 327 uio.uio_iovcnt = 1; 328 uio.uio_offset = offset; 329 uio.uio_resid = count; 330 uio.uio_segflg = UIO_SYSSPACE; 331 uio.uio_rw = UIO_WRITE; 332 uio.uio_td = td; 333 334 if ((ap->a_sync & VM_PAGER_PUT_SYNC) == 0) 335 iomode = NFSWRITE_UNSTABLE; 336 else 337 iomode = NFSWRITE_FILESYNC; 338 339 error = ncl_writerpc(vp, &uio, cred, &iomode, &must_commit, 0); 340 341 pmap_qremove(kva, npages); 342 relpbuf(bp, &ncl_pbuf_freecnt); 343 344 if (!error) { 345 int nwritten = round_page(count - uio.uio_resid) / PAGE_SIZE; 346 for (i = 0; i < nwritten; i++) { 347 rtvals[i] = VM_PAGER_OK; 348 vm_page_undirty(pages[i]); 349 } 350 if (must_commit) { 351 ncl_clearcommit(vp->v_mount); 352 } 353 } 354 return rtvals[0]; 355 } 356 357 /* 358 * For nfs, cache consistency can only be maintained approximately. 359 * Although RFC1094 does not specify the criteria, the following is 360 * believed to be compatible with the reference port. 361 * For nfs: 362 * If the file's modify time on the server has changed since the 363 * last read rpc or you have written to the file, 364 * you may have lost data cache consistency with the 365 * server, so flush all of the file's data out of the cache. 366 * Then force a getattr rpc to ensure that you have up to date 367 * attributes. 368 * NB: This implies that cache data can be read when up to 369 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 370 * attributes this could be forced by setting n_attrstamp to 0 before 371 * the VOP_GETATTR() call. 372 */ 373 static inline int 374 nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred) 375 { 376 int error = 0; 377 struct vattr vattr; 378 struct nfsnode *np = VTONFS(vp); 379 int old_lock; 380 381 /* 382 * Grab the exclusive lock before checking whether the cache is 383 * consistent. 384 * XXX - We can make this cheaper later (by acquiring cheaper locks). 385 * But for now, this suffices. 386 */ 387 old_lock = ncl_upgrade_vnlock(vp); 388 if (vp->v_iflag & VI_DOOMED) { 389 ncl_downgrade_vnlock(vp, old_lock); 390 return (EBADF); 391 } 392 393 mtx_lock(&np->n_mtx); 394 if (np->n_flag & NMODIFIED) { 395 mtx_unlock(&np->n_mtx); 396 if (vp->v_type != VREG) { 397 if (vp->v_type != VDIR) 398 panic("nfs: bioread, not dir"); 399 ncl_invaldir(vp); 400 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 401 if (error) 402 goto out; 403 } 404 np->n_attrstamp = 0; 405 error = VOP_GETATTR(vp, &vattr, cred); 406 if (error) 407 goto out; 408 mtx_lock(&np->n_mtx); 409 np->n_mtime = vattr.va_mtime; 410 mtx_unlock(&np->n_mtx); 411 } else { 412 mtx_unlock(&np->n_mtx); 413 error = VOP_GETATTR(vp, &vattr, cred); 414 if (error) 415 return (error); 416 mtx_lock(&np->n_mtx); 417 if ((np->n_flag & NSIZECHANGED) 418 || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) { 419 mtx_unlock(&np->n_mtx); 420 if (vp->v_type == VDIR) 421 ncl_invaldir(vp); 422 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 423 if (error) 424 goto out; 425 mtx_lock(&np->n_mtx); 426 np->n_mtime = vattr.va_mtime; 427 np->n_flag &= ~NSIZECHANGED; 428 } 429 mtx_unlock(&np->n_mtx); 430 } 431 out: 432 ncl_downgrade_vnlock(vp, old_lock); 433 return error; 434 } 435 436 /* 437 * Vnode op for read using bio 438 */ 439 int 440 ncl_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) 441 { 442 struct nfsnode *np = VTONFS(vp); 443 int biosize, i; 444 struct buf *bp, *rabp; 445 struct thread *td; 446 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 447 daddr_t lbn, rabn; 448 int bcount; 449 int seqcount; 450 int nra, error = 0, n = 0, on = 0; 451 452 KASSERT(uio->uio_rw == UIO_READ, ("ncl_read mode")); 453 if (uio->uio_resid == 0) 454 return (0); 455 if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ 456 return (EINVAL); 457 td = uio->uio_td; 458 459 mtx_lock(&nmp->nm_mtx); 460 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 461 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 462 mtx_unlock(&nmp->nm_mtx); 463 (void)ncl_fsinfo(nmp, vp, cred, td); 464 mtx_lock(&nmp->nm_mtx); 465 } 466 if (nmp->nm_rsize == 0 || nmp->nm_readdirsize == 0) 467 (void) newnfs_iosize(nmp); 468 mtx_unlock(&nmp->nm_mtx); 469 470 if (vp->v_type != VDIR && 471 (uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 472 return (EFBIG); 473 474 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG)) 475 /* No caching/ no readaheads. Just read data into the user buffer */ 476 return ncl_readrpc(vp, uio, cred); 477 478 biosize = vp->v_mount->mnt_stat.f_iosize; 479 seqcount = (int)((off_t)(ioflag >> IO_SEQSHIFT) * biosize / BKVASIZE); 480 481 error = nfs_bioread_check_cons(vp, td, cred); 482 if (error) 483 return error; 484 485 do { 486 u_quad_t nsize; 487 488 mtx_lock(&np->n_mtx); 489 nsize = np->n_size; 490 mtx_unlock(&np->n_mtx); 491 492 switch (vp->v_type) { 493 case VREG: 494 NFSINCRGLOBAL(newnfsstats.biocache_reads); 495 lbn = uio->uio_offset / biosize; 496 on = uio->uio_offset & (biosize - 1); 497 498 /* 499 * Start the read ahead(s), as required. 500 */ 501 if (nmp->nm_readahead > 0) { 502 for (nra = 0; nra < nmp->nm_readahead && nra < seqcount && 503 (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) { 504 rabn = lbn + 1 + nra; 505 if (incore(&vp->v_bufobj, rabn) == NULL) { 506 rabp = nfs_getcacheblk(vp, rabn, biosize, td); 507 if (!rabp) { 508 error = newnfs_sigintr(nmp, td); 509 return (error ? error : EINTR); 510 } 511 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 512 rabp->b_flags |= B_ASYNC; 513 rabp->b_iocmd = BIO_READ; 514 vfs_busy_pages(rabp, 0); 515 if (ncl_asyncio(nmp, rabp, cred, td)) { 516 rabp->b_flags |= B_INVAL; 517 rabp->b_ioflags |= BIO_ERROR; 518 vfs_unbusy_pages(rabp); 519 brelse(rabp); 520 break; 521 } 522 } else { 523 brelse(rabp); 524 } 525 } 526 } 527 } 528 529 /* Note that bcount is *not* DEV_BSIZE aligned. */ 530 bcount = biosize; 531 if ((off_t)lbn * biosize >= nsize) { 532 bcount = 0; 533 } else if ((off_t)(lbn + 1) * biosize > nsize) { 534 bcount = nsize - (off_t)lbn * biosize; 535 } 536 bp = nfs_getcacheblk(vp, lbn, bcount, td); 537 538 if (!bp) { 539 error = newnfs_sigintr(nmp, td); 540 return (error ? error : EINTR); 541 } 542 543 /* 544 * If B_CACHE is not set, we must issue the read. If this 545 * fails, we return an error. 546 */ 547 548 if ((bp->b_flags & B_CACHE) == 0) { 549 bp->b_iocmd = BIO_READ; 550 vfs_busy_pages(bp, 0); 551 error = ncl_doio(vp, bp, cred, td, 0); 552 if (error) { 553 brelse(bp); 554 return (error); 555 } 556 } 557 558 /* 559 * on is the offset into the current bp. Figure out how many 560 * bytes we can copy out of the bp. Note that bcount is 561 * NOT DEV_BSIZE aligned. 562 * 563 * Then figure out how many bytes we can copy into the uio. 564 */ 565 566 n = 0; 567 if (on < bcount) 568 n = min((unsigned)(bcount - on), uio->uio_resid); 569 break; 570 case VLNK: 571 NFSINCRGLOBAL(newnfsstats.biocache_readlinks); 572 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, td); 573 if (!bp) { 574 error = newnfs_sigintr(nmp, td); 575 return (error ? error : EINTR); 576 } 577 if ((bp->b_flags & B_CACHE) == 0) { 578 bp->b_iocmd = BIO_READ; 579 vfs_busy_pages(bp, 0); 580 error = ncl_doio(vp, bp, cred, td, 0); 581 if (error) { 582 bp->b_ioflags |= BIO_ERROR; 583 brelse(bp); 584 return (error); 585 } 586 } 587 n = min(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 588 on = 0; 589 break; 590 case VDIR: 591 NFSINCRGLOBAL(newnfsstats.biocache_readdirs); 592 if (np->n_direofoffset 593 && uio->uio_offset >= np->n_direofoffset) { 594 return (0); 595 } 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 return (error ? error : EINTR); 602 } 603 if ((bp->b_flags & B_CACHE) == 0) { 604 bp->b_iocmd = BIO_READ; 605 vfs_busy_pages(bp, 0); 606 error = ncl_doio(vp, bp, cred, td, 0); 607 if (error) { 608 brelse(bp); 609 } 610 while (error == NFSERR_BAD_COOKIE) { 611 ncl_invaldir(vp); 612 error = ncl_vinvalbuf(vp, 0, td, 1); 613 /* 614 * Yuck! The directory has been modified on the 615 * server. The only way to get the block is by 616 * reading from the beginning to get all the 617 * offset cookies. 618 * 619 * Leave the last bp intact unless there is an error. 620 * Loop back up to the while if the error is another 621 * NFSERR_BAD_COOKIE (double yuch!). 622 */ 623 for (i = 0; i <= lbn && !error; i++) { 624 if (np->n_direofoffset 625 && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) 626 return (0); 627 bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, td); 628 if (!bp) { 629 error = newnfs_sigintr(nmp, td); 630 return (error ? error : EINTR); 631 } 632 if ((bp->b_flags & B_CACHE) == 0) { 633 bp->b_iocmd = BIO_READ; 634 vfs_busy_pages(bp, 0); 635 error = ncl_doio(vp, bp, cred, td, 0); 636 /* 637 * no error + B_INVAL == directory EOF, 638 * use the block. 639 */ 640 if (error == 0 && (bp->b_flags & B_INVAL)) 641 break; 642 } 643 /* 644 * An error will throw away the block and the 645 * for loop will break out. If no error and this 646 * is not the block we want, we throw away the 647 * block and go for the next one via the for loop. 648 */ 649 if (error || i < lbn) 650 brelse(bp); 651 } 652 } 653 /* 654 * The above while is repeated if we hit another cookie 655 * error. If we hit an error and it wasn't a cookie error, 656 * we give up. 657 */ 658 if (error) 659 return (error); 660 } 661 662 /* 663 * If not eof and read aheads are enabled, start one. 664 * (You need the current block first, so that you have the 665 * directory offset cookie of the next block.) 666 */ 667 if (nmp->nm_readahead > 0 && 668 (bp->b_flags & B_INVAL) == 0 && 669 (np->n_direofoffset == 0 || 670 (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && 671 incore(&vp->v_bufobj, lbn + 1) == NULL) { 672 rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td); 673 if (rabp) { 674 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 675 rabp->b_flags |= B_ASYNC; 676 rabp->b_iocmd = BIO_READ; 677 vfs_busy_pages(rabp, 0); 678 if (ncl_asyncio(nmp, rabp, cred, td)) { 679 rabp->b_flags |= B_INVAL; 680 rabp->b_ioflags |= BIO_ERROR; 681 vfs_unbusy_pages(rabp); 682 brelse(rabp); 683 } 684 } else { 685 brelse(rabp); 686 } 687 } 688 } 689 /* 690 * Unlike VREG files, whos buffer size ( bp->b_bcount ) is 691 * chopped for the EOF condition, we cannot tell how large 692 * NFS directories are going to be until we hit EOF. So 693 * an NFS directory buffer is *not* chopped to its EOF. Now, 694 * it just so happens that b_resid will effectively chop it 695 * to EOF. *BUT* this information is lost if the buffer goes 696 * away and is reconstituted into a B_CACHE state ( due to 697 * being VMIO ) later. So we keep track of the directory eof 698 * in np->n_direofoffset and chop it off as an extra step 699 * right here. 700 */ 701 n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); 702 if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset) 703 n = np->n_direofoffset - uio->uio_offset; 704 break; 705 default: 706 ncl_printf(" ncl_bioread: type %x unexpected\n", vp->v_type); 707 bp = NULL; 708 break; 709 }; 710 711 if (n > 0) { 712 error = uiomove(bp->b_data + on, (int)n, uio); 713 } 714 if (vp->v_type == VLNK) 715 n = 0; 716 if (bp != NULL) 717 brelse(bp); 718 } while (error == 0 && uio->uio_resid > 0 && n > 0); 719 return (error); 720 } 721 722 /* 723 * The NFS write path cannot handle iovecs with len > 1. So we need to 724 * break up iovecs accordingly (restricting them to wsize). 725 * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf). 726 * For the ASYNC case, 2 copies are needed. The first a copy from the 727 * user buffer to a staging buffer and then a second copy from the staging 728 * buffer to mbufs. This can be optimized by copying from the user buffer 729 * directly into mbufs and passing the chain down, but that requires a 730 * fair amount of re-working of the relevant codepaths (and can be done 731 * later). 732 */ 733 static int 734 nfs_directio_write(vp, uiop, cred, ioflag) 735 struct vnode *vp; 736 struct uio *uiop; 737 struct ucred *cred; 738 int ioflag; 739 { 740 int error; 741 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 742 struct thread *td = uiop->uio_td; 743 int size; 744 int wsize; 745 746 mtx_lock(&nmp->nm_mtx); 747 wsize = nmp->nm_wsize; 748 mtx_unlock(&nmp->nm_mtx); 749 if (ioflag & IO_SYNC) { 750 int iomode, must_commit; 751 struct uio uio; 752 struct iovec iov; 753 do_sync: 754 while (uiop->uio_resid > 0) { 755 size = min(uiop->uio_resid, wsize); 756 size = min(uiop->uio_iov->iov_len, size); 757 iov.iov_base = uiop->uio_iov->iov_base; 758 iov.iov_len = size; 759 uio.uio_iov = &iov; 760 uio.uio_iovcnt = 1; 761 uio.uio_offset = uiop->uio_offset; 762 uio.uio_resid = size; 763 uio.uio_segflg = UIO_USERSPACE; 764 uio.uio_rw = UIO_WRITE; 765 uio.uio_td = td; 766 iomode = NFSWRITE_FILESYNC; 767 error = ncl_writerpc(vp, &uio, cred, &iomode, 768 &must_commit, 0); 769 KASSERT((must_commit == 0), 770 ("ncl_directio_write: Did not commit write")); 771 if (error) 772 return (error); 773 uiop->uio_offset += size; 774 uiop->uio_resid -= size; 775 if (uiop->uio_iov->iov_len <= size) { 776 uiop->uio_iovcnt--; 777 uiop->uio_iov++; 778 } else { 779 uiop->uio_iov->iov_base = 780 (char *)uiop->uio_iov->iov_base + size; 781 uiop->uio_iov->iov_len -= size; 782 } 783 } 784 } else { 785 struct uio *t_uio; 786 struct iovec *t_iov; 787 struct buf *bp; 788 789 /* 790 * Break up the write into blocksize chunks and hand these 791 * over to nfsiod's for write back. 792 * Unfortunately, this incurs a copy of the data. Since 793 * the user could modify the buffer before the write is 794 * initiated. 795 * 796 * The obvious optimization here is that one of the 2 copies 797 * in the async write path can be eliminated by copying the 798 * data here directly into mbufs and passing the mbuf chain 799 * down. But that will require a fair amount of re-working 800 * of the code and can be done if there's enough interest 801 * in NFS directio access. 802 */ 803 while (uiop->uio_resid > 0) { 804 size = min(uiop->uio_resid, wsize); 805 size = min(uiop->uio_iov->iov_len, size); 806 bp = getpbuf(&ncl_pbuf_freecnt); 807 t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); 808 t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); 809 t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); 810 t_iov->iov_len = size; 811 t_uio->uio_iov = t_iov; 812 t_uio->uio_iovcnt = 1; 813 t_uio->uio_offset = uiop->uio_offset; 814 t_uio->uio_resid = size; 815 t_uio->uio_segflg = UIO_SYSSPACE; 816 t_uio->uio_rw = UIO_WRITE; 817 t_uio->uio_td = td; 818 bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, size); 819 bp->b_flags |= B_DIRECT; 820 bp->b_iocmd = BIO_WRITE; 821 if (cred != NOCRED) { 822 crhold(cred); 823 bp->b_wcred = cred; 824 } else 825 bp->b_wcred = NOCRED; 826 bp->b_caller1 = (void *)t_uio; 827 bp->b_vp = vp; 828 error = ncl_asyncio(nmp, bp, NOCRED, td); 829 if (error) { 830 free(t_iov->iov_base, M_NFSDIRECTIO); 831 free(t_iov, M_NFSDIRECTIO); 832 free(t_uio, M_NFSDIRECTIO); 833 bp->b_vp = NULL; 834 relpbuf(bp, &ncl_pbuf_freecnt); 835 if (error == EINTR) 836 return (error); 837 goto do_sync; 838 } 839 uiop->uio_offset += size; 840 uiop->uio_resid -= size; 841 if (uiop->uio_iov->iov_len <= size) { 842 uiop->uio_iovcnt--; 843 uiop->uio_iov++; 844 } else { 845 uiop->uio_iov->iov_base = 846 (char *)uiop->uio_iov->iov_base + size; 847 uiop->uio_iov->iov_len -= size; 848 } 849 } 850 } 851 return (0); 852 } 853 854 /* 855 * Vnode op for write using bio 856 */ 857 int 858 ncl_write(struct vop_write_args *ap) 859 { 860 int biosize; 861 struct uio *uio = ap->a_uio; 862 struct thread *td = uio->uio_td; 863 struct vnode *vp = ap->a_vp; 864 struct nfsnode *np = VTONFS(vp); 865 struct ucred *cred = ap->a_cred; 866 int ioflag = ap->a_ioflag; 867 struct buf *bp; 868 struct vattr vattr; 869 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 870 daddr_t lbn; 871 int bcount; 872 int n, on, error = 0; 873 struct proc *p = td?td->td_proc:NULL; 874 875 KASSERT(uio->uio_rw == UIO_WRITE, ("ncl_write mode")); 876 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 877 ("ncl_write proc")); 878 if (vp->v_type != VREG) 879 return (EIO); 880 mtx_lock(&np->n_mtx); 881 if (np->n_flag & NWRITEERR) { 882 np->n_flag &= ~NWRITEERR; 883 mtx_unlock(&np->n_mtx); 884 return (np->n_error); 885 } else 886 mtx_unlock(&np->n_mtx); 887 mtx_lock(&nmp->nm_mtx); 888 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 889 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 890 mtx_unlock(&nmp->nm_mtx); 891 (void)ncl_fsinfo(nmp, vp, cred, td); 892 mtx_lock(&nmp->nm_mtx); 893 } 894 if (nmp->nm_wsize == 0) 895 (void) newnfs_iosize(nmp); 896 mtx_unlock(&nmp->nm_mtx); 897 898 /* 899 * Synchronously flush pending buffers if we are in synchronous 900 * mode or if we are appending. 901 */ 902 if (ioflag & (IO_APPEND | IO_SYNC)) { 903 mtx_lock(&np->n_mtx); 904 if (np->n_flag & NMODIFIED) { 905 mtx_unlock(&np->n_mtx); 906 #ifdef notyet /* Needs matching nonblock semantics elsewhere, too. */ 907 /* 908 * Require non-blocking, synchronous writes to 909 * dirty files to inform the program it needs 910 * to fsync(2) explicitly. 911 */ 912 if (ioflag & IO_NDELAY) 913 return (EAGAIN); 914 #endif 915 flush_and_restart: 916 np->n_attrstamp = 0; 917 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 918 if (error) 919 return (error); 920 } else 921 mtx_unlock(&np->n_mtx); 922 } 923 924 /* 925 * If IO_APPEND then load uio_offset. We restart here if we cannot 926 * get the append lock. 927 */ 928 if (ioflag & IO_APPEND) { 929 np->n_attrstamp = 0; 930 error = VOP_GETATTR(vp, &vattr, cred); 931 if (error) 932 return (error); 933 mtx_lock(&np->n_mtx); 934 uio->uio_offset = np->n_size; 935 mtx_unlock(&np->n_mtx); 936 } 937 938 if (uio->uio_offset < 0) 939 return (EINVAL); 940 if ((uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 941 return (EFBIG); 942 if (uio->uio_resid == 0) 943 return (0); 944 945 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && vp->v_type == VREG) 946 return nfs_directio_write(vp, uio, cred, ioflag); 947 948 /* 949 * Maybe this should be above the vnode op call, but so long as 950 * file servers have no limits, i don't think it matters 951 */ 952 if (p != NULL) { 953 PROC_LOCK(p); 954 if (uio->uio_offset + uio->uio_resid > 955 lim_cur(p, RLIMIT_FSIZE)) { 956 psignal(p, SIGXFSZ); 957 PROC_UNLOCK(p); 958 return (EFBIG); 959 } 960 PROC_UNLOCK(p); 961 } 962 963 biosize = vp->v_mount->mnt_stat.f_iosize; 964 /* 965 * Find all of this file's B_NEEDCOMMIT buffers. If our writes 966 * would exceed the local maximum per-file write commit size when 967 * combined with those, we must decide whether to flush, 968 * go synchronous, or return error. We don't bother checking 969 * IO_UNIT -- we just make all writes atomic anyway, as there's 970 * no point optimizing for something that really won't ever happen. 971 */ 972 if (!(ioflag & IO_SYNC)) { 973 int nflag; 974 975 mtx_lock(&np->n_mtx); 976 nflag = np->n_flag; 977 mtx_unlock(&np->n_mtx); 978 int needrestart = 0; 979 if (nmp->nm_wcommitsize < uio->uio_resid) { 980 /* 981 * If this request could not possibly be completed 982 * without exceeding the maximum outstanding write 983 * commit size, see if we can convert it into a 984 * synchronous write operation. 985 */ 986 if (ioflag & IO_NDELAY) 987 return (EAGAIN); 988 ioflag |= IO_SYNC; 989 if (nflag & NMODIFIED) 990 needrestart = 1; 991 } else if (nflag & NMODIFIED) { 992 int wouldcommit = 0; 993 BO_LOCK(&vp->v_bufobj); 994 if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { 995 TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, 996 b_bobufs) { 997 if (bp->b_flags & B_NEEDCOMMIT) 998 wouldcommit += bp->b_bcount; 999 } 1000 } 1001 BO_UNLOCK(&vp->v_bufobj); 1002 /* 1003 * Since we're not operating synchronously and 1004 * bypassing the buffer cache, we are in a commit 1005 * and holding all of these buffers whether 1006 * transmitted or not. If not limited, this 1007 * will lead to the buffer cache deadlocking, 1008 * as no one else can flush our uncommitted buffers. 1009 */ 1010 wouldcommit += uio->uio_resid; 1011 /* 1012 * If we would initially exceed the maximum 1013 * outstanding write commit size, flush and restart. 1014 */ 1015 if (wouldcommit > nmp->nm_wcommitsize) 1016 needrestart = 1; 1017 } 1018 if (needrestart) 1019 goto flush_and_restart; 1020 } 1021 1022 do { 1023 NFSINCRGLOBAL(newnfsstats.biocache_writes); 1024 lbn = uio->uio_offset / biosize; 1025 on = uio->uio_offset & (biosize-1); 1026 n = min((unsigned)(biosize - on), uio->uio_resid); 1027 again: 1028 /* 1029 * Handle direct append and file extension cases, calculate 1030 * unaligned buffer size. 1031 */ 1032 mtx_lock(&np->n_mtx); 1033 if (uio->uio_offset == np->n_size && n) { 1034 mtx_unlock(&np->n_mtx); 1035 /* 1036 * Get the buffer (in its pre-append state to maintain 1037 * B_CACHE if it was previously set). Resize the 1038 * nfsnode after we have locked the buffer to prevent 1039 * readers from reading garbage. 1040 */ 1041 bcount = on; 1042 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1043 1044 if (bp != NULL) { 1045 long save; 1046 1047 mtx_lock(&np->n_mtx); 1048 np->n_size = uio->uio_offset + n; 1049 np->n_flag |= NMODIFIED; 1050 vnode_pager_setsize(vp, np->n_size); 1051 mtx_unlock(&np->n_mtx); 1052 1053 save = bp->b_flags & B_CACHE; 1054 bcount += n; 1055 allocbuf(bp, bcount); 1056 bp->b_flags |= save; 1057 } 1058 } else { 1059 /* 1060 * Obtain the locked cache block first, and then 1061 * adjust the file's size as appropriate. 1062 */ 1063 bcount = on + n; 1064 if ((off_t)lbn * biosize + bcount < np->n_size) { 1065 if ((off_t)(lbn + 1) * biosize < np->n_size) 1066 bcount = biosize; 1067 else 1068 bcount = np->n_size - (off_t)lbn * biosize; 1069 } 1070 mtx_unlock(&np->n_mtx); 1071 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1072 mtx_lock(&np->n_mtx); 1073 if (uio->uio_offset + n > np->n_size) { 1074 np->n_size = uio->uio_offset + n; 1075 np->n_flag |= NMODIFIED; 1076 vnode_pager_setsize(vp, np->n_size); 1077 } 1078 mtx_unlock(&np->n_mtx); 1079 } 1080 1081 if (!bp) { 1082 error = newnfs_sigintr(nmp, td); 1083 if (!error) 1084 error = EINTR; 1085 break; 1086 } 1087 1088 /* 1089 * Issue a READ if B_CACHE is not set. In special-append 1090 * mode, B_CACHE is based on the buffer prior to the write 1091 * op and is typically set, avoiding the read. If a read 1092 * is required in special append mode, the server will 1093 * probably send us a short-read since we extended the file 1094 * on our end, resulting in b_resid == 0 and, thusly, 1095 * B_CACHE getting set. 1096 * 1097 * We can also avoid issuing the read if the write covers 1098 * the entire buffer. We have to make sure the buffer state 1099 * is reasonable in this case since we will not be initiating 1100 * I/O. See the comments in kern/vfs_bio.c's getblk() for 1101 * more information. 1102 * 1103 * B_CACHE may also be set due to the buffer being cached 1104 * normally. 1105 */ 1106 1107 if (on == 0 && n == bcount) { 1108 bp->b_flags |= B_CACHE; 1109 bp->b_flags &= ~B_INVAL; 1110 bp->b_ioflags &= ~BIO_ERROR; 1111 } 1112 1113 if ((bp->b_flags & B_CACHE) == 0) { 1114 bp->b_iocmd = BIO_READ; 1115 vfs_busy_pages(bp, 0); 1116 error = ncl_doio(vp, bp, cred, td, 0); 1117 if (error) { 1118 brelse(bp); 1119 break; 1120 } 1121 } 1122 if (bp->b_wcred == NOCRED) 1123 bp->b_wcred = crhold(cred); 1124 mtx_lock(&np->n_mtx); 1125 np->n_flag |= NMODIFIED; 1126 mtx_unlock(&np->n_mtx); 1127 1128 /* 1129 * If dirtyend exceeds file size, chop it down. This should 1130 * not normally occur but there is an append race where it 1131 * might occur XXX, so we log it. 1132 * 1133 * If the chopping creates a reverse-indexed or degenerate 1134 * situation with dirtyoff/end, we 0 both of them. 1135 */ 1136 1137 if (bp->b_dirtyend > bcount) { 1138 ncl_printf("NFS append race @%lx:%d\n", 1139 (long)bp->b_blkno * DEV_BSIZE, 1140 bp->b_dirtyend - bcount); 1141 bp->b_dirtyend = bcount; 1142 } 1143 1144 if (bp->b_dirtyoff >= bp->b_dirtyend) 1145 bp->b_dirtyoff = bp->b_dirtyend = 0; 1146 1147 /* 1148 * If the new write will leave a contiguous dirty 1149 * area, just update the b_dirtyoff and b_dirtyend, 1150 * otherwise force a write rpc of the old dirty area. 1151 * 1152 * While it is possible to merge discontiguous writes due to 1153 * our having a B_CACHE buffer ( and thus valid read data 1154 * for the hole), we don't because it could lead to 1155 * significant cache coherency problems with multiple clients, 1156 * especially if locking is implemented later on. 1157 * 1158 * as an optimization we could theoretically maintain 1159 * a linked list of discontinuous areas, but we would still 1160 * have to commit them separately so there isn't much 1161 * advantage to it except perhaps a bit of asynchronization. 1162 */ 1163 1164 if (bp->b_dirtyend > 0 && 1165 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 1166 if (bwrite(bp) == EINTR) { 1167 error = EINTR; 1168 break; 1169 } 1170 goto again; 1171 } 1172 1173 error = uiomove((char *)bp->b_data + on, n, uio); 1174 1175 /* 1176 * Since this block is being modified, it must be written 1177 * again and not just committed. Since write clustering does 1178 * not work for the stage 1 data write, only the stage 2 1179 * commit rpc, we have to clear B_CLUSTEROK as well. 1180 */ 1181 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1182 1183 if (error) { 1184 bp->b_ioflags |= BIO_ERROR; 1185 brelse(bp); 1186 break; 1187 } 1188 1189 /* 1190 * Only update dirtyoff/dirtyend if not a degenerate 1191 * condition. 1192 */ 1193 if (n) { 1194 if (bp->b_dirtyend > 0) { 1195 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 1196 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 1197 } else { 1198 bp->b_dirtyoff = on; 1199 bp->b_dirtyend = on + n; 1200 } 1201 vfs_bio_set_valid(bp, on, n); 1202 } 1203 1204 /* 1205 * If IO_SYNC do bwrite(). 1206 * 1207 * IO_INVAL appears to be unused. The idea appears to be 1208 * to turn off caching in this case. Very odd. XXX 1209 */ 1210 if ((ioflag & IO_SYNC)) { 1211 if (ioflag & IO_INVAL) 1212 bp->b_flags |= B_NOCACHE; 1213 error = bwrite(bp); 1214 if (error) 1215 break; 1216 } else if ((n + on) == biosize) { 1217 bp->b_flags |= B_ASYNC; 1218 (void) ncl_writebp(bp, 0, NULL); 1219 } else { 1220 bdwrite(bp); 1221 } 1222 } while (uio->uio_resid > 0 && n > 0); 1223 1224 return (error); 1225 } 1226 1227 /* 1228 * Get an nfs cache block. 1229 * 1230 * Allocate a new one if the block isn't currently in the cache 1231 * and return the block marked busy. If the calling process is 1232 * interrupted by a signal for an interruptible mount point, return 1233 * NULL. 1234 * 1235 * The caller must carefully deal with the possible B_INVAL state of 1236 * the buffer. ncl_doio() clears B_INVAL (and ncl_asyncio() clears it 1237 * indirectly), so synchronous reads can be issued without worrying about 1238 * the B_INVAL state. We have to be a little more careful when dealing 1239 * with writes (see comments in nfs_write()) when extending a file past 1240 * its EOF. 1241 */ 1242 static struct buf * 1243 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td) 1244 { 1245 struct buf *bp; 1246 struct mount *mp; 1247 struct nfsmount *nmp; 1248 1249 mp = vp->v_mount; 1250 nmp = VFSTONFS(mp); 1251 1252 if (nmp->nm_flag & NFSMNT_INT) { 1253 sigset_t oldset; 1254 1255 newnfs_set_sigmask(td, &oldset); 1256 bp = getblk(vp, bn, size, NFS_PCATCH, 0, 0); 1257 newnfs_restore_sigmask(td, &oldset); 1258 while (bp == NULL) { 1259 if (newnfs_sigintr(nmp, td)) 1260 return (NULL); 1261 bp = getblk(vp, bn, size, 0, 2 * hz, 0); 1262 } 1263 } else { 1264 bp = getblk(vp, bn, size, 0, 0, 0); 1265 } 1266 1267 if (vp->v_type == VREG) { 1268 int biosize; 1269 1270 biosize = mp->mnt_stat.f_iosize; 1271 bp->b_blkno = bn * (biosize / DEV_BSIZE); 1272 } 1273 return (bp); 1274 } 1275 1276 /* 1277 * Flush and invalidate all dirty buffers. If another process is already 1278 * doing the flush, just wait for completion. 1279 */ 1280 int 1281 ncl_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg) 1282 { 1283 struct nfsnode *np = VTONFS(vp); 1284 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1285 int error = 0, slpflag, slptimeo; 1286 int old_lock = 0; 1287 1288 ASSERT_VOP_LOCKED(vp, "ncl_vinvalbuf"); 1289 1290 if ((nmp->nm_flag & NFSMNT_INT) == 0) 1291 intrflg = 0; 1292 if ((nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF)) 1293 intrflg = 1; 1294 if (intrflg) { 1295 slpflag = NFS_PCATCH; 1296 slptimeo = 2 * hz; 1297 } else { 1298 slpflag = 0; 1299 slptimeo = 0; 1300 } 1301 1302 old_lock = ncl_upgrade_vnlock(vp); 1303 if (vp->v_iflag & VI_DOOMED) { 1304 /* 1305 * Since vgonel() uses the generic vinvalbuf() to flush 1306 * dirty buffers and it does not call this function, it 1307 * is safe to just return OK when VI_DOOMED is set. 1308 */ 1309 ncl_downgrade_vnlock(vp, old_lock); 1310 return (0); 1311 } 1312 1313 /* 1314 * Now, flush as required. 1315 */ 1316 if ((flags & V_SAVE) && (vp->v_bufobj.bo_object != NULL)) { 1317 VM_OBJECT_LOCK(vp->v_bufobj.bo_object); 1318 vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); 1319 VM_OBJECT_UNLOCK(vp->v_bufobj.bo_object); 1320 /* 1321 * If the page clean was interrupted, fail the invalidation. 1322 * Not doing so, we run the risk of losing dirty pages in the 1323 * vinvalbuf() call below. 1324 */ 1325 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1326 goto out; 1327 } 1328 1329 error = vinvalbuf(vp, flags, slpflag, 0); 1330 while (error) { 1331 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1332 goto out; 1333 error = vinvalbuf(vp, flags, 0, slptimeo); 1334 } 1335 mtx_lock(&np->n_mtx); 1336 if (np->n_directio_asyncwr == 0) 1337 np->n_flag &= ~NMODIFIED; 1338 mtx_unlock(&np->n_mtx); 1339 out: 1340 ncl_downgrade_vnlock(vp, old_lock); 1341 return error; 1342 } 1343 1344 /* 1345 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 1346 * This is mainly to avoid queueing async I/O requests when the nfsiods 1347 * are all hung on a dead server. 1348 * 1349 * Note: ncl_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp 1350 * is eventually dequeued by the async daemon, ncl_doio() *will*. 1351 */ 1352 int 1353 ncl_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) 1354 { 1355 int iod; 1356 int gotiod; 1357 int slpflag = 0; 1358 int slptimeo = 0; 1359 int error, error2; 1360 1361 /* 1362 * Unless iothreadcnt is set > 0, don't bother with async I/O 1363 * threads. For LAN environments, they don't buy any significant 1364 * performance improvement that you can't get with large block 1365 * sizes. 1366 */ 1367 if (nmp->nm_readahead == 0) 1368 return (EPERM); 1369 1370 /* 1371 * Commits are usually short and sweet so lets save some cpu and 1372 * leave the async daemons for more important rpc's (such as reads 1373 * and writes). 1374 */ 1375 mtx_lock(&ncl_iod_mutex); 1376 if (bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && 1377 (nmp->nm_bufqiods > ncl_numasync / 2)) { 1378 mtx_unlock(&ncl_iod_mutex); 1379 return(EIO); 1380 } 1381 again: 1382 if (nmp->nm_flag & NFSMNT_INT) 1383 slpflag = NFS_PCATCH; 1384 gotiod = FALSE; 1385 1386 /* 1387 * Find a free iod to process this request. 1388 */ 1389 for (iod = 0; iod < ncl_numasync; iod++) 1390 if (ncl_iodwant[iod] == NFSIOD_AVAILABLE) { 1391 gotiod = TRUE; 1392 break; 1393 } 1394 1395 /* 1396 * Try to create one if none are free. 1397 */ 1398 if (!gotiod) { 1399 iod = ncl_nfsiodnew(1); 1400 if (iod != -1) 1401 gotiod = TRUE; 1402 } 1403 1404 if (gotiod) { 1405 /* 1406 * Found one, so wake it up and tell it which 1407 * mount to process. 1408 */ 1409 NFS_DPF(ASYNCIO, ("ncl_asyncio: waking iod %d for mount %p\n", 1410 iod, nmp)); 1411 ncl_iodwant[iod] = NFSIOD_NOT_AVAILABLE; 1412 ncl_iodmount[iod] = nmp; 1413 nmp->nm_bufqiods++; 1414 wakeup(&ncl_iodwant[iod]); 1415 } 1416 1417 /* 1418 * If none are free, we may already have an iod working on this mount 1419 * point. If so, it will process our request. 1420 */ 1421 if (!gotiod) { 1422 if (nmp->nm_bufqiods > 0) { 1423 NFS_DPF(ASYNCIO, 1424 ("ncl_asyncio: %d iods are already processing mount %p\n", 1425 nmp->nm_bufqiods, nmp)); 1426 gotiod = TRUE; 1427 } 1428 } 1429 1430 /* 1431 * If we have an iod which can process the request, then queue 1432 * the buffer. 1433 */ 1434 if (gotiod) { 1435 /* 1436 * Ensure that the queue never grows too large. We still want 1437 * to asynchronize so we block rather then return EIO. 1438 */ 1439 while (nmp->nm_bufqlen >= 2*ncl_numasync) { 1440 NFS_DPF(ASYNCIO, 1441 ("ncl_asyncio: waiting for mount %p queue to drain\n", nmp)); 1442 nmp->nm_bufqwant = TRUE; 1443 error = newnfs_msleep(td, &nmp->nm_bufq, 1444 &ncl_iod_mutex, slpflag | PRIBIO, "nfsaio", 1445 slptimeo); 1446 if (error) { 1447 error2 = newnfs_sigintr(nmp, td); 1448 if (error2) { 1449 mtx_unlock(&ncl_iod_mutex); 1450 return (error2); 1451 } 1452 if (slpflag == NFS_PCATCH) { 1453 slpflag = 0; 1454 slptimeo = 2 * hz; 1455 } 1456 } 1457 /* 1458 * We might have lost our iod while sleeping, 1459 * so check and loop if nescessary. 1460 */ 1461 if (nmp->nm_bufqiods == 0) { 1462 NFS_DPF(ASYNCIO, 1463 ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1464 goto again; 1465 } 1466 } 1467 1468 /* We might have lost our nfsiod */ 1469 if (nmp->nm_bufqiods == 0) { 1470 NFS_DPF(ASYNCIO, 1471 ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1472 goto again; 1473 } 1474 1475 if (bp->b_iocmd == BIO_READ) { 1476 if (bp->b_rcred == NOCRED && cred != NOCRED) 1477 bp->b_rcred = crhold(cred); 1478 } else { 1479 if (bp->b_wcred == NOCRED && cred != NOCRED) 1480 bp->b_wcred = crhold(cred); 1481 } 1482 1483 if (bp->b_flags & B_REMFREE) 1484 bremfreef(bp); 1485 BUF_KERNPROC(bp); 1486 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 1487 nmp->nm_bufqlen++; 1488 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1489 mtx_lock(&(VTONFS(bp->b_vp))->n_mtx); 1490 VTONFS(bp->b_vp)->n_flag |= NMODIFIED; 1491 VTONFS(bp->b_vp)->n_directio_asyncwr++; 1492 mtx_unlock(&(VTONFS(bp->b_vp))->n_mtx); 1493 } 1494 mtx_unlock(&ncl_iod_mutex); 1495 return (0); 1496 } 1497 1498 mtx_unlock(&ncl_iod_mutex); 1499 1500 /* 1501 * All the iods are busy on other mounts, so return EIO to 1502 * force the caller to process the i/o synchronously. 1503 */ 1504 NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods available, i/o is synchronous\n")); 1505 return (EIO); 1506 } 1507 1508 void 1509 ncl_doio_directwrite(struct buf *bp) 1510 { 1511 int iomode, must_commit; 1512 struct uio *uiop = (struct uio *)bp->b_caller1; 1513 char *iov_base = uiop->uio_iov->iov_base; 1514 1515 iomode = NFSWRITE_FILESYNC; 1516 uiop->uio_td = NULL; /* NULL since we're in nfsiod */ 1517 ncl_writerpc(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit, 0); 1518 KASSERT((must_commit == 0), ("ncl_doio_directwrite: Did not commit write")); 1519 free(iov_base, M_NFSDIRECTIO); 1520 free(uiop->uio_iov, M_NFSDIRECTIO); 1521 free(uiop, M_NFSDIRECTIO); 1522 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1523 struct nfsnode *np = VTONFS(bp->b_vp); 1524 mtx_lock(&np->n_mtx); 1525 np->n_directio_asyncwr--; 1526 if (np->n_directio_asyncwr == 0) { 1527 np->n_flag &= ~NMODIFIED; 1528 if ((np->n_flag & NFSYNCWAIT)) { 1529 np->n_flag &= ~NFSYNCWAIT; 1530 wakeup((caddr_t)&np->n_directio_asyncwr); 1531 } 1532 } 1533 mtx_unlock(&np->n_mtx); 1534 } 1535 bp->b_vp = NULL; 1536 relpbuf(bp, &ncl_pbuf_freecnt); 1537 } 1538 1539 /* 1540 * Do an I/O operation to/from a cache block. This may be called 1541 * synchronously or from an nfsiod. 1542 */ 1543 int 1544 ncl_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td, 1545 int called_from_strategy) 1546 { 1547 struct uio *uiop; 1548 struct nfsnode *np; 1549 struct nfsmount *nmp; 1550 int error = 0, iomode, must_commit = 0; 1551 struct uio uio; 1552 struct iovec io; 1553 struct proc *p = td ? td->td_proc : NULL; 1554 uint8_t iocmd; 1555 1556 np = VTONFS(vp); 1557 nmp = VFSTONFS(vp->v_mount); 1558 uiop = &uio; 1559 uiop->uio_iov = &io; 1560 uiop->uio_iovcnt = 1; 1561 uiop->uio_segflg = UIO_SYSSPACE; 1562 uiop->uio_td = td; 1563 1564 /* 1565 * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We 1566 * do this here so we do not have to do it in all the code that 1567 * calls us. 1568 */ 1569 bp->b_flags &= ~B_INVAL; 1570 bp->b_ioflags &= ~BIO_ERROR; 1571 1572 KASSERT(!(bp->b_flags & B_DONE), ("ncl_doio: bp %p already marked done", bp)); 1573 iocmd = bp->b_iocmd; 1574 if (iocmd == BIO_READ) { 1575 io.iov_len = uiop->uio_resid = bp->b_bcount; 1576 io.iov_base = bp->b_data; 1577 uiop->uio_rw = UIO_READ; 1578 1579 switch (vp->v_type) { 1580 case VREG: 1581 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1582 NFSINCRGLOBAL(newnfsstats.read_bios); 1583 error = ncl_readrpc(vp, uiop, cr); 1584 1585 if (!error) { 1586 if (uiop->uio_resid) { 1587 /* 1588 * If we had a short read with no error, we must have 1589 * hit a file hole. We should zero-fill the remainder. 1590 * This can also occur if the server hits the file EOF. 1591 * 1592 * Holes used to be able to occur due to pending 1593 * writes, but that is not possible any longer. 1594 */ 1595 int nread = bp->b_bcount - uiop->uio_resid; 1596 int left = uiop->uio_resid; 1597 1598 if (left > 0) 1599 bzero((char *)bp->b_data + nread, left); 1600 uiop->uio_resid = 0; 1601 } 1602 } 1603 /* ASSERT_VOP_LOCKED(vp, "ncl_doio"); */ 1604 if (p && (vp->v_vflag & VV_TEXT)) { 1605 mtx_lock(&np->n_mtx); 1606 if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.na_mtime)) { 1607 mtx_unlock(&np->n_mtx); 1608 PROC_LOCK(p); 1609 killproc(p, "text file modification"); 1610 PROC_UNLOCK(p); 1611 } else 1612 mtx_unlock(&np->n_mtx); 1613 } 1614 break; 1615 case VLNK: 1616 uiop->uio_offset = (off_t)0; 1617 NFSINCRGLOBAL(newnfsstats.readlink_bios); 1618 error = ncl_readlinkrpc(vp, uiop, cr); 1619 break; 1620 case VDIR: 1621 NFSINCRGLOBAL(newnfsstats.readdir_bios); 1622 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; 1623 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) { 1624 error = ncl_readdirplusrpc(vp, uiop, cr, td); 1625 if (error == NFSERR_NOTSUPP) 1626 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1627 } 1628 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1629 error = ncl_readdirrpc(vp, uiop, cr, td); 1630 /* 1631 * end-of-directory sets B_INVAL but does not generate an 1632 * error. 1633 */ 1634 if (error == 0 && uiop->uio_resid == bp->b_bcount) 1635 bp->b_flags |= B_INVAL; 1636 break; 1637 default: 1638 ncl_printf("ncl_doio: type %x unexpected\n", vp->v_type); 1639 break; 1640 }; 1641 if (error) { 1642 bp->b_ioflags |= BIO_ERROR; 1643 bp->b_error = error; 1644 } 1645 } else { 1646 /* 1647 * If we only need to commit, try to commit 1648 */ 1649 if (bp->b_flags & B_NEEDCOMMIT) { 1650 int retv; 1651 off_t off; 1652 1653 off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff; 1654 retv = ncl_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff, 1655 bp->b_wcred, td); 1656 if (retv == 0) { 1657 bp->b_dirtyoff = bp->b_dirtyend = 0; 1658 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1659 bp->b_resid = 0; 1660 bufdone(bp); 1661 return (0); 1662 } 1663 if (retv == NFSERR_STALEWRITEVERF) { 1664 ncl_clearcommit(vp->v_mount); 1665 } 1666 } 1667 1668 /* 1669 * Setup for actual write 1670 */ 1671 mtx_lock(&np->n_mtx); 1672 if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size) 1673 bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE; 1674 mtx_unlock(&np->n_mtx); 1675 1676 if (bp->b_dirtyend > bp->b_dirtyoff) { 1677 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1678 - bp->b_dirtyoff; 1679 uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE 1680 + bp->b_dirtyoff; 1681 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1682 uiop->uio_rw = UIO_WRITE; 1683 NFSINCRGLOBAL(newnfsstats.write_bios); 1684 1685 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) 1686 iomode = NFSWRITE_UNSTABLE; 1687 else 1688 iomode = NFSWRITE_FILESYNC; 1689 1690 error = ncl_writerpc(vp, uiop, cr, &iomode, &must_commit, 1691 called_from_strategy); 1692 1693 /* 1694 * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try 1695 * to cluster the buffers needing commit. This will allow 1696 * the system to submit a single commit rpc for the whole 1697 * cluster. We can do this even if the buffer is not 100% 1698 * dirty (relative to the NFS blocksize), so we optimize the 1699 * append-to-file-case. 1700 * 1701 * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be 1702 * cleared because write clustering only works for commit 1703 * rpc's, not for the data portion of the write). 1704 */ 1705 1706 if (!error && iomode == NFSWRITE_UNSTABLE) { 1707 bp->b_flags |= B_NEEDCOMMIT; 1708 if (bp->b_dirtyoff == 0 1709 && bp->b_dirtyend == bp->b_bcount) 1710 bp->b_flags |= B_CLUSTEROK; 1711 } else { 1712 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1713 } 1714 1715 /* 1716 * For an interrupted write, the buffer is still valid 1717 * and the write hasn't been pushed to the server yet, 1718 * so we can't set BIO_ERROR and report the interruption 1719 * by setting B_EINTR. For the B_ASYNC case, B_EINTR 1720 * is not relevant, so the rpc attempt is essentially 1721 * a noop. For the case of a V3 write rpc not being 1722 * committed to stable storage, the block is still 1723 * dirty and requires either a commit rpc or another 1724 * write rpc with iomode == NFSV3WRITE_FILESYNC before 1725 * the block is reused. This is indicated by setting 1726 * the B_DELWRI and B_NEEDCOMMIT flags. 1727 * 1728 * EIO is returned by ncl_writerpc() to indicate a recoverable 1729 * write error and is handled as above, except that 1730 * B_EINTR isn't set. One cause of this is a stale stateid 1731 * error for the RPC that indicates recovery is required, 1732 * when called with called_from_strategy != 0. 1733 * 1734 * If the buffer is marked B_PAGING, it does not reside on 1735 * the vp's paging queues so we cannot call bdirty(). The 1736 * bp in this case is not an NFS cache block so we should 1737 * be safe. XXX 1738 * 1739 * The logic below breaks up errors into recoverable and 1740 * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE 1741 * and keep the buffer around for potential write retries. 1742 * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) 1743 * and save the error in the nfsnode. This is less than ideal 1744 * but necessary. Keeping such buffers around could potentially 1745 * cause buffer exhaustion eventually (they can never be written 1746 * out, so will get constantly be re-dirtied). It also causes 1747 * all sorts of vfs panics. For non-recoverable write errors, 1748 * also invalidate the attrcache, so we'll be forced to go over 1749 * the wire for this object, returning an error to user on next 1750 * call (most of the time). 1751 */ 1752 if (error == EINTR || error == EIO || error == ETIMEDOUT 1753 || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1754 int s; 1755 1756 s = splbio(); 1757 bp->b_flags &= ~(B_INVAL|B_NOCACHE); 1758 if ((bp->b_flags & B_PAGING) == 0) { 1759 bdirty(bp); 1760 bp->b_flags &= ~B_DONE; 1761 } 1762 if ((error == EINTR || error == ETIMEDOUT) && 1763 (bp->b_flags & B_ASYNC) == 0) 1764 bp->b_flags |= B_EINTR; 1765 splx(s); 1766 } else { 1767 if (error) { 1768 bp->b_ioflags |= BIO_ERROR; 1769 bp->b_flags |= B_INVAL; 1770 bp->b_error = np->n_error = error; 1771 mtx_lock(&np->n_mtx); 1772 np->n_flag |= NWRITEERR; 1773 np->n_attrstamp = 0; 1774 mtx_unlock(&np->n_mtx); 1775 } 1776 bp->b_dirtyoff = bp->b_dirtyend = 0; 1777 } 1778 } else { 1779 bp->b_resid = 0; 1780 bufdone(bp); 1781 return (0); 1782 } 1783 } 1784 bp->b_resid = uiop->uio_resid; 1785 if (must_commit) 1786 ncl_clearcommit(vp->v_mount); 1787 bufdone(bp); 1788 return (error); 1789 } 1790 1791 /* 1792 * Used to aid in handling ftruncate() operations on the NFS client side. 1793 * Truncation creates a number of special problems for NFS. We have to 1794 * throw away VM pages and buffer cache buffers that are beyond EOF, and 1795 * we have to properly handle VM pages or (potentially dirty) buffers 1796 * that straddle the truncation point. 1797 */ 1798 1799 int 1800 ncl_meta_setsize(struct vnode *vp, struct ucred *cred, struct thread *td, u_quad_t nsize) 1801 { 1802 struct nfsnode *np = VTONFS(vp); 1803 u_quad_t tsize; 1804 int biosize = vp->v_mount->mnt_stat.f_iosize; 1805 int error = 0; 1806 1807 mtx_lock(&np->n_mtx); 1808 tsize = np->n_size; 1809 np->n_size = nsize; 1810 mtx_unlock(&np->n_mtx); 1811 1812 if (nsize < tsize) { 1813 struct buf *bp; 1814 daddr_t lbn; 1815 int bufsize; 1816 1817 /* 1818 * vtruncbuf() doesn't get the buffer overlapping the 1819 * truncation point. We may have a B_DELWRI and/or B_CACHE 1820 * buffer that now needs to be truncated. 1821 */ 1822 error = vtruncbuf(vp, cred, td, nsize, biosize); 1823 lbn = nsize / biosize; 1824 bufsize = nsize & (biosize - 1); 1825 bp = nfs_getcacheblk(vp, lbn, bufsize, td); 1826 if (!bp) 1827 return EINTR; 1828 if (bp->b_dirtyoff > bp->b_bcount) 1829 bp->b_dirtyoff = bp->b_bcount; 1830 if (bp->b_dirtyend > bp->b_bcount) 1831 bp->b_dirtyend = bp->b_bcount; 1832 bp->b_flags |= B_RELBUF; /* don't leave garbage around */ 1833 brelse(bp); 1834 } else { 1835 vnode_pager_setsize(vp, nsize); 1836 } 1837 return(error); 1838 } 1839
Cache object: 2cad1e862c38beb4789a14937b2ae206
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