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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/8.3/sys/fs/nfsclient/nfs_clbio.c 231332 2012-02-10 04:01:17Z 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/vmmeter.h> 45 #include <sys/vnode.h> 46 47 #include <vm/vm.h> 48 #include <vm/vm_extern.h> 49 #include <vm/vm_page.h> 50 #include <vm/vm_object.h> 51 #include <vm/vm_pager.h> 52 #include <vm/vnode_pager.h> 53 54 #include <fs/nfs/nfsport.h> 55 #include <fs/nfsclient/nfsmount.h> 56 #include <fs/nfsclient/nfs.h> 57 #include <fs/nfsclient/nfsnode.h> 58 59 extern int newnfs_directio_allow_mmap; 60 extern struct nfsstats newnfsstats; 61 extern struct mtx ncl_iod_mutex; 62 extern int ncl_numasync; 63 extern enum nfsiod_state ncl_iodwant[NFS_MAXASYNCDAEMON]; 64 extern struct nfsmount *ncl_iodmount[NFS_MAXASYNCDAEMON]; 65 extern int newnfs_directio_enable; 66 67 int ncl_pbuf_freecnt = -1; /* start out unlimited */ 68 69 static struct buf *nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, 70 struct thread *td); 71 static int nfs_directio_write(struct vnode *vp, struct uio *uiop, 72 struct ucred *cred, int ioflag); 73 74 /* 75 * Vnode op for VM getpages. 76 */ 77 int 78 ncl_getpages(struct vop_getpages_args *ap) 79 { 80 int i, error, nextoff, size, toff, count, npages; 81 struct uio uio; 82 struct iovec iov; 83 vm_offset_t kva; 84 struct buf *bp; 85 struct vnode *vp; 86 struct thread *td; 87 struct ucred *cred; 88 struct nfsmount *nmp; 89 vm_object_t object; 90 vm_page_t *pages; 91 struct nfsnode *np; 92 93 vp = ap->a_vp; 94 np = VTONFS(vp); 95 td = curthread; /* XXX */ 96 cred = curthread->td_ucred; /* XXX */ 97 nmp = VFSTONFS(vp->v_mount); 98 pages = ap->a_m; 99 count = ap->a_count; 100 101 if ((object = vp->v_object) == NULL) { 102 ncl_printf("nfs_getpages: called with non-merged cache vnode??\n"); 103 return (VM_PAGER_ERROR); 104 } 105 106 if (newnfs_directio_enable && !newnfs_directio_allow_mmap) { 107 mtx_lock(&np->n_mtx); 108 if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 109 mtx_unlock(&np->n_mtx); 110 ncl_printf("nfs_getpages: called on non-cacheable vnode??\n"); 111 return (VM_PAGER_ERROR); 112 } else 113 mtx_unlock(&np->n_mtx); 114 } 115 116 mtx_lock(&nmp->nm_mtx); 117 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 118 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 119 mtx_unlock(&nmp->nm_mtx); 120 /* We'll never get here for v4, because we always have fsinfo */ 121 (void)ncl_fsinfo(nmp, vp, cred, td); 122 } else 123 mtx_unlock(&nmp->nm_mtx); 124 125 npages = btoc(count); 126 127 /* 128 * If the requested page is partially valid, just return it and 129 * allow the pager to zero-out the blanks. Partially valid pages 130 * can only occur at the file EOF. 131 */ 132 VM_OBJECT_LOCK(object); 133 if (pages[ap->a_reqpage]->valid != 0) { 134 vm_page_lock_queues(); 135 for (i = 0; i < npages; ++i) { 136 if (i != ap->a_reqpage) 137 vm_page_free(pages[i]); 138 } 139 vm_page_unlock_queues(); 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(&ncl_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 = ncl_readrpc(vp, &uio, cred); 167 pmap_qremove(kva, npages); 168 169 relpbuf(bp, &ncl_pbuf_freecnt); 170 171 if (error && (uio.uio_resid == count)) { 172 ncl_printf("nfs_getpages: error %d\n", error); 173 VM_OBJECT_LOCK(object); 174 vm_page_lock_queues(); 175 for (i = 0; i < npages; ++i) { 176 if (i != ap->a_reqpage) 177 vm_page_free(pages[i]); 178 } 179 vm_page_unlock_queues(); 180 VM_OBJECT_UNLOCK(object); 181 return (VM_PAGER_ERROR); 182 } 183 184 /* 185 * Calculate the number of bytes read and validate only that number 186 * of bytes. Note that due to pending writes, size may be 0. This 187 * does not mean that the remaining data is invalid! 188 */ 189 190 size = count - uio.uio_resid; 191 VM_OBJECT_LOCK(object); 192 vm_page_lock_queues(); 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 occured 216 * we may have hit a zero-fill section. We simply 217 * leave valid set to 0. 218 */ 219 ; 220 } 221 if (i != ap->a_reqpage) { 222 /* 223 * Whether or not to leave the page activated is up in 224 * the air, but we should put the page on a page queue 225 * somewhere (it already is in the object). Result: 226 * It appears that emperical results show that 227 * deactivating pages is best. 228 */ 229 230 /* 231 * Just in case someone was asking for this page we 232 * now tell them that it is ok to use. 233 */ 234 if (!error) { 235 if (m->oflags & VPO_WANTED) 236 vm_page_activate(m); 237 else 238 vm_page_deactivate(m); 239 vm_page_wakeup(m); 240 } else { 241 vm_page_free(m); 242 } 243 } 244 } 245 vm_page_unlock_queues(); 246 VM_OBJECT_UNLOCK(object); 247 return (0); 248 } 249 250 /* 251 * Vnode op for VM putpages. 252 */ 253 int 254 ncl_putpages(struct vop_putpages_args *ap) 255 { 256 struct uio uio; 257 struct iovec iov; 258 vm_offset_t kva; 259 struct buf *bp; 260 int iomode, must_commit, i, error, npages, count; 261 off_t offset; 262 int *rtvals; 263 struct vnode *vp; 264 struct thread *td; 265 struct ucred *cred; 266 struct nfsmount *nmp; 267 struct nfsnode *np; 268 vm_page_t *pages; 269 270 vp = ap->a_vp; 271 np = VTONFS(vp); 272 td = curthread; /* XXX */ 273 cred = curthread->td_ucred; /* XXX */ 274 nmp = VFSTONFS(vp->v_mount); 275 pages = ap->a_m; 276 count = ap->a_count; 277 rtvals = ap->a_rtvals; 278 npages = btoc(count); 279 offset = IDX_TO_OFF(pages[0]->pindex); 280 281 mtx_lock(&nmp->nm_mtx); 282 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 283 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 284 mtx_unlock(&nmp->nm_mtx); 285 (void)ncl_fsinfo(nmp, vp, cred, td); 286 } else 287 mtx_unlock(&nmp->nm_mtx); 288 289 mtx_lock(&np->n_mtx); 290 if (newnfs_directio_enable && !newnfs_directio_allow_mmap && 291 (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { 292 mtx_unlock(&np->n_mtx); 293 ncl_printf("ncl_putpages: called on noncache-able vnode??\n"); 294 mtx_lock(&np->n_mtx); 295 } 296 297 for (i = 0; i < npages; i++) 298 rtvals[i] = VM_PAGER_ERROR; 299 300 /* 301 * When putting pages, do not extend file past EOF. 302 */ 303 if (offset + count > np->n_size) { 304 count = np->n_size - offset; 305 if (count < 0) 306 count = 0; 307 } 308 mtx_unlock(&np->n_mtx); 309 310 /* 311 * We use only the kva address for the buffer, but this is extremely 312 * convienient and fast. 313 */ 314 bp = getpbuf(&ncl_pbuf_freecnt); 315 316 kva = (vm_offset_t) bp->b_data; 317 pmap_qenter(kva, pages, npages); 318 PCPU_INC(cnt.v_vnodeout); 319 PCPU_ADD(cnt.v_vnodepgsout, count); 320 321 iov.iov_base = (caddr_t) kva; 322 iov.iov_len = count; 323 uio.uio_iov = &iov; 324 uio.uio_iovcnt = 1; 325 uio.uio_offset = offset; 326 uio.uio_resid = count; 327 uio.uio_segflg = UIO_SYSSPACE; 328 uio.uio_rw = UIO_WRITE; 329 uio.uio_td = td; 330 331 if ((ap->a_sync & VM_PAGER_PUT_SYNC) == 0) 332 iomode = NFSWRITE_UNSTABLE; 333 else 334 iomode = NFSWRITE_FILESYNC; 335 336 error = ncl_writerpc(vp, &uio, cred, &iomode, &must_commit, 0); 337 338 pmap_qremove(kva, npages); 339 relpbuf(bp, &ncl_pbuf_freecnt); 340 341 vnode_pager_undirty_pages(pages, rtvals, count - uio.uio_resid); 342 if (must_commit) 343 ncl_clearcommit(vp->v_mount); 344 return rtvals[0]; 345 } 346 347 /* 348 * For nfs, cache consistency can only be maintained approximately. 349 * Although RFC1094 does not specify the criteria, the following is 350 * believed to be compatible with the reference port. 351 * For nfs: 352 * If the file's modify time on the server has changed since the 353 * last read rpc or you have written to the file, 354 * you may have lost data cache consistency with the 355 * server, so flush all of the file's data out of the cache. 356 * Then force a getattr rpc to ensure that you have up to date 357 * attributes. 358 * NB: This implies that cache data can be read when up to 359 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 360 * attributes this could be forced by setting n_attrstamp to 0 before 361 * the VOP_GETATTR() call. 362 */ 363 static inline int 364 nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred) 365 { 366 int error = 0; 367 struct vattr vattr; 368 struct nfsnode *np = VTONFS(vp); 369 int old_lock; 370 371 /* 372 * Grab the exclusive lock before checking whether the cache is 373 * consistent. 374 * XXX - We can make this cheaper later (by acquiring cheaper locks). 375 * But for now, this suffices. 376 */ 377 old_lock = ncl_upgrade_vnlock(vp); 378 if (vp->v_iflag & VI_DOOMED) { 379 ncl_downgrade_vnlock(vp, old_lock); 380 return (EBADF); 381 } 382 383 mtx_lock(&np->n_mtx); 384 if (np->n_flag & NMODIFIED) { 385 mtx_unlock(&np->n_mtx); 386 if (vp->v_type != VREG) { 387 if (vp->v_type != VDIR) 388 panic("nfs: bioread, not dir"); 389 ncl_invaldir(vp); 390 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 391 if (error) 392 goto out; 393 } 394 np->n_attrstamp = 0; 395 error = VOP_GETATTR(vp, &vattr, cred); 396 if (error) 397 goto out; 398 mtx_lock(&np->n_mtx); 399 np->n_mtime = vattr.va_mtime; 400 mtx_unlock(&np->n_mtx); 401 } else { 402 mtx_unlock(&np->n_mtx); 403 error = VOP_GETATTR(vp, &vattr, cred); 404 if (error) 405 return (error); 406 mtx_lock(&np->n_mtx); 407 if ((np->n_flag & NSIZECHANGED) 408 || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) { 409 mtx_unlock(&np->n_mtx); 410 if (vp->v_type == VDIR) 411 ncl_invaldir(vp); 412 error = ncl_vinvalbuf(vp, V_SAVE, td, 1); 413 if (error) 414 goto out; 415 mtx_lock(&np->n_mtx); 416 np->n_mtime = vattr.va_mtime; 417 np->n_flag &= ~NSIZECHANGED; 418 } 419 mtx_unlock(&np->n_mtx); 420 } 421 out: 422 ncl_downgrade_vnlock(vp, old_lock); 423 return error; 424 } 425 426 /* 427 * Vnode op for read using bio 428 */ 429 int 430 ncl_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) 431 { 432 struct nfsnode *np = VTONFS(vp); 433 int biosize, i; 434 struct buf *bp, *rabp; 435 struct thread *td; 436 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 437 daddr_t lbn, rabn; 438 int bcount; 439 int seqcount; 440 int nra, error = 0, n = 0, on = 0; 441 off_t tmp_off; 442 443 KASSERT(uio->uio_rw == UIO_READ, ("ncl_read mode")); 444 if (uio->uio_resid == 0) 445 return (0); 446 if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ 447 return (EINVAL); 448 td = uio->uio_td; 449 450 mtx_lock(&nmp->nm_mtx); 451 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 452 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 453 mtx_unlock(&nmp->nm_mtx); 454 (void)ncl_fsinfo(nmp, vp, cred, td); 455 mtx_lock(&nmp->nm_mtx); 456 } 457 if (nmp->nm_rsize == 0 || nmp->nm_readdirsize == 0) 458 (void) newnfs_iosize(nmp); 459 460 tmp_off = uio->uio_offset + uio->uio_resid; 461 if (vp->v_type != VDIR && 462 (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset)) { 463 mtx_unlock(&nmp->nm_mtx); 464 return (EFBIG); 465 } 466 mtx_unlock(&nmp->nm_mtx); 467 468 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG)) 469 /* No caching/ no readaheads. Just read data into the user buffer */ 470 return ncl_readrpc(vp, uio, cred); 471 472 biosize = vp->v_bufobj.bo_bsize; 473 seqcount = (int)((off_t)(ioflag >> IO_SEQSHIFT) * biosize / BKVASIZE); 474 475 error = nfs_bioread_check_cons(vp, td, cred); 476 if (error) 477 return error; 478 479 do { 480 u_quad_t nsize; 481 482 mtx_lock(&np->n_mtx); 483 nsize = np->n_size; 484 mtx_unlock(&np->n_mtx); 485 486 switch (vp->v_type) { 487 case VREG: 488 NFSINCRGLOBAL(newnfsstats.biocache_reads); 489 lbn = uio->uio_offset / biosize; 490 on = uio->uio_offset & (biosize - 1); 491 492 /* 493 * Start the read ahead(s), as required. 494 */ 495 if (nmp->nm_readahead > 0) { 496 for (nra = 0; nra < nmp->nm_readahead && nra < seqcount && 497 (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) { 498 rabn = lbn + 1 + nra; 499 if (incore(&vp->v_bufobj, rabn) == NULL) { 500 rabp = nfs_getcacheblk(vp, rabn, biosize, td); 501 if (!rabp) { 502 error = newnfs_sigintr(nmp, td); 503 return (error ? error : EINTR); 504 } 505 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 506 rabp->b_flags |= B_ASYNC; 507 rabp->b_iocmd = BIO_READ; 508 vfs_busy_pages(rabp, 0); 509 if (ncl_asyncio(nmp, rabp, cred, td)) { 510 rabp->b_flags |= B_INVAL; 511 rabp->b_ioflags |= BIO_ERROR; 512 vfs_unbusy_pages(rabp); 513 brelse(rabp); 514 break; 515 } 516 } else { 517 brelse(rabp); 518 } 519 } 520 } 521 } 522 523 /* Note that bcount is *not* DEV_BSIZE aligned. */ 524 bcount = biosize; 525 if ((off_t)lbn * biosize >= nsize) { 526 bcount = 0; 527 } else if ((off_t)(lbn + 1) * biosize > nsize) { 528 bcount = nsize - (off_t)lbn * biosize; 529 } 530 bp = nfs_getcacheblk(vp, lbn, bcount, td); 531 532 if (!bp) { 533 error = newnfs_sigintr(nmp, td); 534 return (error ? error : EINTR); 535 } 536 537 /* 538 * If B_CACHE is not set, we must issue the read. If this 539 * fails, we return an error. 540 */ 541 542 if ((bp->b_flags & B_CACHE) == 0) { 543 bp->b_iocmd = BIO_READ; 544 vfs_busy_pages(bp, 0); 545 error = ncl_doio(vp, bp, cred, td, 0); 546 if (error) { 547 brelse(bp); 548 return (error); 549 } 550 } 551 552 /* 553 * on is the offset into the current bp. Figure out how many 554 * bytes we can copy out of the bp. Note that bcount is 555 * NOT DEV_BSIZE aligned. 556 * 557 * Then figure out how many bytes we can copy into the uio. 558 */ 559 560 n = 0; 561 if (on < bcount) 562 n = min((unsigned)(bcount - on), uio->uio_resid); 563 break; 564 case VLNK: 565 NFSINCRGLOBAL(newnfsstats.biocache_readlinks); 566 bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, td); 567 if (!bp) { 568 error = newnfs_sigintr(nmp, td); 569 return (error ? error : EINTR); 570 } 571 if ((bp->b_flags & B_CACHE) == 0) { 572 bp->b_iocmd = BIO_READ; 573 vfs_busy_pages(bp, 0); 574 error = ncl_doio(vp, bp, cred, td, 0); 575 if (error) { 576 bp->b_ioflags |= BIO_ERROR; 577 brelse(bp); 578 return (error); 579 } 580 } 581 n = min(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 582 on = 0; 583 break; 584 case VDIR: 585 NFSINCRGLOBAL(newnfsstats.biocache_readdirs); 586 if (np->n_direofoffset 587 && uio->uio_offset >= np->n_direofoffset) { 588 return (0); 589 } 590 lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ; 591 on = uio->uio_offset & (NFS_DIRBLKSIZ - 1); 592 bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, td); 593 if (!bp) { 594 error = newnfs_sigintr(nmp, td); 595 return (error ? error : EINTR); 596 } 597 if ((bp->b_flags & B_CACHE) == 0) { 598 bp->b_iocmd = BIO_READ; 599 vfs_busy_pages(bp, 0); 600 error = ncl_doio(vp, bp, cred, td, 0); 601 if (error) { 602 brelse(bp); 603 } 604 while (error == NFSERR_BAD_COOKIE) { 605 ncl_invaldir(vp); 606 error = ncl_vinvalbuf(vp, 0, td, 1); 607 /* 608 * Yuck! The directory has been modified on the 609 * server. The only way to get the block is by 610 * reading from the beginning to get all the 611 * offset cookies. 612 * 613 * Leave the last bp intact unless there is an error. 614 * Loop back up to the while if the error is another 615 * NFSERR_BAD_COOKIE (double yuch!). 616 */ 617 for (i = 0; i <= lbn && !error; i++) { 618 if (np->n_direofoffset 619 && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset) 620 return (0); 621 bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, td); 622 if (!bp) { 623 error = newnfs_sigintr(nmp, td); 624 return (error ? error : EINTR); 625 } 626 if ((bp->b_flags & B_CACHE) == 0) { 627 bp->b_iocmd = BIO_READ; 628 vfs_busy_pages(bp, 0); 629 error = ncl_doio(vp, bp, cred, td, 0); 630 /* 631 * no error + B_INVAL == directory EOF, 632 * use the block. 633 */ 634 if (error == 0 && (bp->b_flags & B_INVAL)) 635 break; 636 } 637 /* 638 * An error will throw away the block and the 639 * for loop will break out. If no error and this 640 * is not the block we want, we throw away the 641 * block and go for the next one via the for loop. 642 */ 643 if (error || i < lbn) 644 brelse(bp); 645 } 646 } 647 /* 648 * The above while is repeated if we hit another cookie 649 * error. If we hit an error and it wasn't a cookie error, 650 * we give up. 651 */ 652 if (error) 653 return (error); 654 } 655 656 /* 657 * If not eof and read aheads are enabled, start one. 658 * (You need the current block first, so that you have the 659 * directory offset cookie of the next block.) 660 */ 661 if (nmp->nm_readahead > 0 && 662 (bp->b_flags & B_INVAL) == 0 && 663 (np->n_direofoffset == 0 || 664 (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && 665 incore(&vp->v_bufobj, lbn + 1) == NULL) { 666 rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td); 667 if (rabp) { 668 if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { 669 rabp->b_flags |= B_ASYNC; 670 rabp->b_iocmd = BIO_READ; 671 vfs_busy_pages(rabp, 0); 672 if (ncl_asyncio(nmp, rabp, cred, td)) { 673 rabp->b_flags |= B_INVAL; 674 rabp->b_ioflags |= BIO_ERROR; 675 vfs_unbusy_pages(rabp); 676 brelse(rabp); 677 } 678 } else { 679 brelse(rabp); 680 } 681 } 682 } 683 /* 684 * Unlike VREG files, whos buffer size ( bp->b_bcount ) is 685 * chopped for the EOF condition, we cannot tell how large 686 * NFS directories are going to be until we hit EOF. So 687 * an NFS directory buffer is *not* chopped to its EOF. Now, 688 * it just so happens that b_resid will effectively chop it 689 * to EOF. *BUT* this information is lost if the buffer goes 690 * away and is reconstituted into a B_CACHE state ( due to 691 * being VMIO ) later. So we keep track of the directory eof 692 * in np->n_direofoffset and chop it off as an extra step 693 * right here. 694 */ 695 n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); 696 if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset) 697 n = np->n_direofoffset - uio->uio_offset; 698 break; 699 default: 700 ncl_printf(" ncl_bioread: type %x unexpected\n", vp->v_type); 701 bp = NULL; 702 break; 703 }; 704 705 if (n > 0) { 706 error = uiomove(bp->b_data + on, (int)n, uio); 707 } 708 if (vp->v_type == VLNK) 709 n = 0; 710 if (bp != NULL) 711 brelse(bp); 712 } while (error == 0 && uio->uio_resid > 0 && n > 0); 713 return (error); 714 } 715 716 /* 717 * The NFS write path cannot handle iovecs with len > 1. So we need to 718 * break up iovecs accordingly (restricting them to wsize). 719 * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf). 720 * For the ASYNC case, 2 copies are needed. The first a copy from the 721 * user buffer to a staging buffer and then a second copy from the staging 722 * buffer to mbufs. This can be optimized by copying from the user buffer 723 * directly into mbufs and passing the chain down, but that requires a 724 * fair amount of re-working of the relevant codepaths (and can be done 725 * later). 726 */ 727 static int 728 nfs_directio_write(vp, uiop, cred, ioflag) 729 struct vnode *vp; 730 struct uio *uiop; 731 struct ucred *cred; 732 int ioflag; 733 { 734 int error; 735 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 736 struct thread *td = uiop->uio_td; 737 int size; 738 int wsize; 739 740 mtx_lock(&nmp->nm_mtx); 741 wsize = nmp->nm_wsize; 742 mtx_unlock(&nmp->nm_mtx); 743 if (ioflag & IO_SYNC) { 744 int iomode, must_commit; 745 struct uio uio; 746 struct iovec iov; 747 do_sync: 748 while (uiop->uio_resid > 0) { 749 size = min(uiop->uio_resid, wsize); 750 size = min(uiop->uio_iov->iov_len, size); 751 iov.iov_base = uiop->uio_iov->iov_base; 752 iov.iov_len = size; 753 uio.uio_iov = &iov; 754 uio.uio_iovcnt = 1; 755 uio.uio_offset = uiop->uio_offset; 756 uio.uio_resid = size; 757 uio.uio_segflg = UIO_USERSPACE; 758 uio.uio_rw = UIO_WRITE; 759 uio.uio_td = td; 760 iomode = NFSWRITE_FILESYNC; 761 error = ncl_writerpc(vp, &uio, cred, &iomode, 762 &must_commit, 0); 763 KASSERT((must_commit == 0), 764 ("ncl_directio_write: Did not commit write")); 765 if (error) 766 return (error); 767 uiop->uio_offset += size; 768 uiop->uio_resid -= size; 769 if (uiop->uio_iov->iov_len <= size) { 770 uiop->uio_iovcnt--; 771 uiop->uio_iov++; 772 } else { 773 uiop->uio_iov->iov_base = 774 (char *)uiop->uio_iov->iov_base + size; 775 uiop->uio_iov->iov_len -= size; 776 } 777 } 778 } else { 779 struct uio *t_uio; 780 struct iovec *t_iov; 781 struct buf *bp; 782 783 /* 784 * Break up the write into blocksize chunks and hand these 785 * over to nfsiod's for write back. 786 * Unfortunately, this incurs a copy of the data. Since 787 * the user could modify the buffer before the write is 788 * initiated. 789 * 790 * The obvious optimization here is that one of the 2 copies 791 * in the async write path can be eliminated by copying the 792 * data here directly into mbufs and passing the mbuf chain 793 * down. But that will require a fair amount of re-working 794 * of the code and can be done if there's enough interest 795 * in NFS directio access. 796 */ 797 while (uiop->uio_resid > 0) { 798 size = min(uiop->uio_resid, wsize); 799 size = min(uiop->uio_iov->iov_len, size); 800 bp = getpbuf(&ncl_pbuf_freecnt); 801 t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); 802 t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); 803 t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); 804 t_iov->iov_len = size; 805 t_uio->uio_iov = t_iov; 806 t_uio->uio_iovcnt = 1; 807 t_uio->uio_offset = uiop->uio_offset; 808 t_uio->uio_resid = size; 809 t_uio->uio_segflg = UIO_SYSSPACE; 810 t_uio->uio_rw = UIO_WRITE; 811 t_uio->uio_td = td; 812 bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, size); 813 bp->b_flags |= B_DIRECT; 814 bp->b_iocmd = BIO_WRITE; 815 if (cred != NOCRED) { 816 crhold(cred); 817 bp->b_wcred = cred; 818 } else 819 bp->b_wcred = NOCRED; 820 bp->b_caller1 = (void *)t_uio; 821 bp->b_vp = vp; 822 error = ncl_asyncio(nmp, bp, NOCRED, td); 823 if (error) { 824 free(t_iov->iov_base, M_NFSDIRECTIO); 825 free(t_iov, M_NFSDIRECTIO); 826 free(t_uio, M_NFSDIRECTIO); 827 bp->b_vp = NULL; 828 relpbuf(bp, &ncl_pbuf_freecnt); 829 if (error == EINTR) 830 return (error); 831 goto do_sync; 832 } 833 uiop->uio_offset += size; 834 uiop->uio_resid -= size; 835 if (uiop->uio_iov->iov_len <= size) { 836 uiop->uio_iovcnt--; 837 uiop->uio_iov++; 838 } else { 839 uiop->uio_iov->iov_base = 840 (char *)uiop->uio_iov->iov_base + size; 841 uiop->uio_iov->iov_len -= size; 842 } 843 } 844 } 845 return (0); 846 } 847 848 /* 849 * Vnode op for write using bio 850 */ 851 int 852 ncl_write(struct vop_write_args *ap) 853 { 854 int biosize; 855 struct uio *uio = ap->a_uio; 856 struct thread *td = uio->uio_td; 857 struct vnode *vp = ap->a_vp; 858 struct nfsnode *np = VTONFS(vp); 859 struct ucred *cred = ap->a_cred; 860 int ioflag = ap->a_ioflag; 861 struct buf *bp; 862 struct vattr vattr; 863 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 864 daddr_t lbn; 865 int bcount; 866 int n, on, error = 0; 867 off_t tmp_off; 868 869 KASSERT(uio->uio_rw == UIO_WRITE, ("ncl_write mode")); 870 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 871 ("ncl_write proc")); 872 if (vp->v_type != VREG) 873 return (EIO); 874 mtx_lock(&np->n_mtx); 875 if (np->n_flag & NWRITEERR) { 876 np->n_flag &= ~NWRITEERR; 877 mtx_unlock(&np->n_mtx); 878 return (np->n_error); 879 } else 880 mtx_unlock(&np->n_mtx); 881 mtx_lock(&nmp->nm_mtx); 882 if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && 883 (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { 884 mtx_unlock(&nmp->nm_mtx); 885 (void)ncl_fsinfo(nmp, vp, cred, td); 886 mtx_lock(&nmp->nm_mtx); 887 } 888 if (nmp->nm_wsize == 0) 889 (void) newnfs_iosize(nmp); 890 mtx_unlock(&nmp->nm_mtx); 891 892 /* 893 * Synchronously flush pending buffers if we are in synchronous 894 * mode or if we are appending. 895 */ 896 if (ioflag & (IO_APPEND | IO_SYNC)) { 897 mtx_lock(&np->n_mtx); 898 if (np->n_flag & NMODIFIED) { 899 mtx_unlock(&np->n_mtx); 900 #ifdef notyet /* Needs matching nonblock semantics elsewhere, too. */ 901 /* 902 * Require non-blocking, synchronous writes to 903 * dirty files to inform the program it needs 904 * to fsync(2) explicitly. 905 */ 906 if (ioflag & IO_NDELAY) 907 return (EAGAIN); 908 #endif 909 flush_and_restart: 910 np->n_attrstamp = 0; 911 error = ncl_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 error = VOP_GETATTR(vp, &vattr, cred); 925 if (error) 926 return (error); 927 mtx_lock(&np->n_mtx); 928 uio->uio_offset = np->n_size; 929 mtx_unlock(&np->n_mtx); 930 } 931 932 if (uio->uio_offset < 0) 933 return (EINVAL); 934 tmp_off = uio->uio_offset + uio->uio_resid; 935 if (tmp_off > nmp->nm_maxfilesize || tmp_off < uio->uio_offset) 936 return (EFBIG); 937 if (uio->uio_resid == 0) 938 return (0); 939 940 if (newnfs_directio_enable && (ioflag & IO_DIRECT) && vp->v_type == VREG) 941 return nfs_directio_write(vp, uio, cred, ioflag); 942 943 /* 944 * Maybe this should be above the vnode op call, but so long as 945 * file servers have no limits, i don't think it matters 946 */ 947 if (vn_rlimit_fsize(vp, uio, td)) 948 return (EFBIG); 949 950 biosize = vp->v_bufobj.bo_bsize; 951 /* 952 * Find all of this file's B_NEEDCOMMIT buffers. If our writes 953 * would exceed the local maximum per-file write commit size when 954 * combined with those, we must decide whether to flush, 955 * go synchronous, or return error. We don't bother checking 956 * IO_UNIT -- we just make all writes atomic anyway, as there's 957 * no point optimizing for something that really won't ever happen. 958 */ 959 if (!(ioflag & IO_SYNC)) { 960 int nflag; 961 962 mtx_lock(&np->n_mtx); 963 nflag = np->n_flag; 964 mtx_unlock(&np->n_mtx); 965 int needrestart = 0; 966 if (nmp->nm_wcommitsize < uio->uio_resid) { 967 /* 968 * If this request could not possibly be completed 969 * without exceeding the maximum outstanding write 970 * commit size, see if we can convert it into a 971 * synchronous write operation. 972 */ 973 if (ioflag & IO_NDELAY) 974 return (EAGAIN); 975 ioflag |= IO_SYNC; 976 if (nflag & NMODIFIED) 977 needrestart = 1; 978 } else if (nflag & NMODIFIED) { 979 int wouldcommit = 0; 980 BO_LOCK(&vp->v_bufobj); 981 if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { 982 TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, 983 b_bobufs) { 984 if (bp->b_flags & B_NEEDCOMMIT) 985 wouldcommit += bp->b_bcount; 986 } 987 } 988 BO_UNLOCK(&vp->v_bufobj); 989 /* 990 * Since we're not operating synchronously and 991 * bypassing the buffer cache, we are in a commit 992 * and holding all of these buffers whether 993 * transmitted or not. If not limited, this 994 * will lead to the buffer cache deadlocking, 995 * as no one else can flush our uncommitted buffers. 996 */ 997 wouldcommit += uio->uio_resid; 998 /* 999 * If we would initially exceed the maximum 1000 * outstanding write commit size, flush and restart. 1001 */ 1002 if (wouldcommit > nmp->nm_wcommitsize) 1003 needrestart = 1; 1004 } 1005 if (needrestart) 1006 goto flush_and_restart; 1007 } 1008 1009 do { 1010 NFSINCRGLOBAL(newnfsstats.biocache_writes); 1011 lbn = uio->uio_offset / biosize; 1012 on = uio->uio_offset & (biosize-1); 1013 n = min((unsigned)(biosize - on), uio->uio_resid); 1014 again: 1015 /* 1016 * Handle direct append and file extension cases, calculate 1017 * unaligned buffer size. 1018 */ 1019 mtx_lock(&np->n_mtx); 1020 if (uio->uio_offset == np->n_size && n) { 1021 mtx_unlock(&np->n_mtx); 1022 /* 1023 * Get the buffer (in its pre-append state to maintain 1024 * B_CACHE if it was previously set). Resize the 1025 * nfsnode after we have locked the buffer to prevent 1026 * readers from reading garbage. 1027 */ 1028 bcount = on; 1029 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1030 1031 if (bp != NULL) { 1032 long save; 1033 1034 mtx_lock(&np->n_mtx); 1035 np->n_size = uio->uio_offset + n; 1036 np->n_flag |= NMODIFIED; 1037 vnode_pager_setsize(vp, np->n_size); 1038 mtx_unlock(&np->n_mtx); 1039 1040 save = bp->b_flags & B_CACHE; 1041 bcount += n; 1042 allocbuf(bp, bcount); 1043 bp->b_flags |= save; 1044 } 1045 } else { 1046 /* 1047 * Obtain the locked cache block first, and then 1048 * adjust the file's size as appropriate. 1049 */ 1050 bcount = on + n; 1051 if ((off_t)lbn * biosize + bcount < np->n_size) { 1052 if ((off_t)(lbn + 1) * biosize < np->n_size) 1053 bcount = biosize; 1054 else 1055 bcount = np->n_size - (off_t)lbn * biosize; 1056 } 1057 mtx_unlock(&np->n_mtx); 1058 bp = nfs_getcacheblk(vp, lbn, bcount, td); 1059 mtx_lock(&np->n_mtx); 1060 if (uio->uio_offset + n > np->n_size) { 1061 np->n_size = uio->uio_offset + n; 1062 np->n_flag |= NMODIFIED; 1063 vnode_pager_setsize(vp, np->n_size); 1064 } 1065 mtx_unlock(&np->n_mtx); 1066 } 1067 1068 if (!bp) { 1069 error = newnfs_sigintr(nmp, td); 1070 if (!error) 1071 error = EINTR; 1072 break; 1073 } 1074 1075 /* 1076 * Issue a READ if B_CACHE is not set. In special-append 1077 * mode, B_CACHE is based on the buffer prior to the write 1078 * op and is typically set, avoiding the read. If a read 1079 * is required in special append mode, the server will 1080 * probably send us a short-read since we extended the file 1081 * on our end, resulting in b_resid == 0 and, thusly, 1082 * B_CACHE getting set. 1083 * 1084 * We can also avoid issuing the read if the write covers 1085 * the entire buffer. We have to make sure the buffer state 1086 * is reasonable in this case since we will not be initiating 1087 * I/O. See the comments in kern/vfs_bio.c's getblk() for 1088 * more information. 1089 * 1090 * B_CACHE may also be set due to the buffer being cached 1091 * normally. 1092 */ 1093 1094 if (on == 0 && n == bcount) { 1095 bp->b_flags |= B_CACHE; 1096 bp->b_flags &= ~B_INVAL; 1097 bp->b_ioflags &= ~BIO_ERROR; 1098 } 1099 1100 if ((bp->b_flags & B_CACHE) == 0) { 1101 bp->b_iocmd = BIO_READ; 1102 vfs_busy_pages(bp, 0); 1103 error = ncl_doio(vp, bp, cred, td, 0); 1104 if (error) { 1105 brelse(bp); 1106 break; 1107 } 1108 } 1109 if (bp->b_wcred == NOCRED) 1110 bp->b_wcred = crhold(cred); 1111 mtx_lock(&np->n_mtx); 1112 np->n_flag |= NMODIFIED; 1113 mtx_unlock(&np->n_mtx); 1114 1115 /* 1116 * If dirtyend exceeds file size, chop it down. This should 1117 * not normally occur but there is an append race where it 1118 * might occur XXX, so we log it. 1119 * 1120 * If the chopping creates a reverse-indexed or degenerate 1121 * situation with dirtyoff/end, we 0 both of them. 1122 */ 1123 1124 if (bp->b_dirtyend > bcount) { 1125 ncl_printf("NFS append race @%lx:%d\n", 1126 (long)bp->b_blkno * DEV_BSIZE, 1127 bp->b_dirtyend - bcount); 1128 bp->b_dirtyend = bcount; 1129 } 1130 1131 if (bp->b_dirtyoff >= bp->b_dirtyend) 1132 bp->b_dirtyoff = bp->b_dirtyend = 0; 1133 1134 /* 1135 * If the new write will leave a contiguous dirty 1136 * area, just update the b_dirtyoff and b_dirtyend, 1137 * otherwise force a write rpc of the old dirty area. 1138 * 1139 * While it is possible to merge discontiguous writes due to 1140 * our having a B_CACHE buffer ( and thus valid read data 1141 * for the hole), we don't because it could lead to 1142 * significant cache coherency problems with multiple clients, 1143 * especially if locking is implemented later on. 1144 * 1145 * as an optimization we could theoretically maintain 1146 * a linked list of discontinuous areas, but we would still 1147 * have to commit them separately so there isn't much 1148 * advantage to it except perhaps a bit of asynchronization. 1149 */ 1150 1151 if (bp->b_dirtyend > 0 && 1152 (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { 1153 if (bwrite(bp) == EINTR) { 1154 error = EINTR; 1155 break; 1156 } 1157 goto again; 1158 } 1159 1160 error = uiomove((char *)bp->b_data + on, n, uio); 1161 1162 /* 1163 * Since this block is being modified, it must be written 1164 * again and not just committed. Since write clustering does 1165 * not work for the stage 1 data write, only the stage 2 1166 * commit rpc, we have to clear B_CLUSTEROK as well. 1167 */ 1168 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1169 1170 if (error) { 1171 bp->b_ioflags |= BIO_ERROR; 1172 brelse(bp); 1173 break; 1174 } 1175 1176 /* 1177 * Only update dirtyoff/dirtyend if not a degenerate 1178 * condition. 1179 */ 1180 if (n) { 1181 if (bp->b_dirtyend > 0) { 1182 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 1183 bp->b_dirtyend = max((on + n), bp->b_dirtyend); 1184 } else { 1185 bp->b_dirtyoff = on; 1186 bp->b_dirtyend = on + n; 1187 } 1188 vfs_bio_set_valid(bp, on, n); 1189 } 1190 1191 /* 1192 * If IO_SYNC do bwrite(). 1193 * 1194 * IO_INVAL appears to be unused. The idea appears to be 1195 * to turn off caching in this case. Very odd. XXX 1196 */ 1197 if ((ioflag & IO_SYNC)) { 1198 if (ioflag & IO_INVAL) 1199 bp->b_flags |= B_NOCACHE; 1200 error = bwrite(bp); 1201 if (error) 1202 break; 1203 } else if ((n + on) == biosize) { 1204 bp->b_flags |= B_ASYNC; 1205 (void) ncl_writebp(bp, 0, NULL); 1206 } else { 1207 bdwrite(bp); 1208 } 1209 } while (uio->uio_resid > 0 && n > 0); 1210 1211 return (error); 1212 } 1213 1214 /* 1215 * Get an nfs cache block. 1216 * 1217 * Allocate a new one if the block isn't currently in the cache 1218 * and return the block marked busy. If the calling process is 1219 * interrupted by a signal for an interruptible mount point, return 1220 * NULL. 1221 * 1222 * The caller must carefully deal with the possible B_INVAL state of 1223 * the buffer. ncl_doio() clears B_INVAL (and ncl_asyncio() clears it 1224 * indirectly), so synchronous reads can be issued without worrying about 1225 * the B_INVAL state. We have to be a little more careful when dealing 1226 * with writes (see comments in nfs_write()) when extending a file past 1227 * its EOF. 1228 */ 1229 static struct buf * 1230 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td) 1231 { 1232 struct buf *bp; 1233 struct mount *mp; 1234 struct nfsmount *nmp; 1235 1236 mp = vp->v_mount; 1237 nmp = VFSTONFS(mp); 1238 1239 if (nmp->nm_flag & NFSMNT_INT) { 1240 sigset_t oldset; 1241 1242 newnfs_set_sigmask(td, &oldset); 1243 bp = getblk(vp, bn, size, NFS_PCATCH, 0, 0); 1244 newnfs_restore_sigmask(td, &oldset); 1245 while (bp == NULL) { 1246 if (newnfs_sigintr(nmp, td)) 1247 return (NULL); 1248 bp = getblk(vp, bn, size, 0, 2 * hz, 0); 1249 } 1250 } else { 1251 bp = getblk(vp, bn, size, 0, 0, 0); 1252 } 1253 1254 if (vp->v_type == VREG) 1255 bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / DEV_BSIZE); 1256 return (bp); 1257 } 1258 1259 /* 1260 * Flush and invalidate all dirty buffers. If another process is already 1261 * doing the flush, just wait for completion. 1262 */ 1263 int 1264 ncl_vinvalbuf(struct vnode *vp, int flags, struct thread *td, int intrflg) 1265 { 1266 struct nfsnode *np = VTONFS(vp); 1267 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1268 int error = 0, slpflag, slptimeo; 1269 int old_lock = 0; 1270 1271 ASSERT_VOP_LOCKED(vp, "ncl_vinvalbuf"); 1272 1273 if ((nmp->nm_flag & NFSMNT_INT) == 0) 1274 intrflg = 0; 1275 if ((nmp->nm_mountp->mnt_kern_flag & MNTK_UNMOUNTF)) 1276 intrflg = 1; 1277 if (intrflg) { 1278 slpflag = NFS_PCATCH; 1279 slptimeo = 2 * hz; 1280 } else { 1281 slpflag = 0; 1282 slptimeo = 0; 1283 } 1284 1285 old_lock = ncl_upgrade_vnlock(vp); 1286 if (vp->v_iflag & VI_DOOMED) { 1287 /* 1288 * Since vgonel() uses the generic vinvalbuf() to flush 1289 * dirty buffers and it does not call this function, it 1290 * is safe to just return OK when VI_DOOMED is set. 1291 */ 1292 ncl_downgrade_vnlock(vp, old_lock); 1293 return (0); 1294 } 1295 1296 /* 1297 * Now, flush as required. 1298 */ 1299 if ((flags & V_SAVE) && (vp->v_bufobj.bo_object != NULL)) { 1300 VM_OBJECT_LOCK(vp->v_bufobj.bo_object); 1301 vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); 1302 VM_OBJECT_UNLOCK(vp->v_bufobj.bo_object); 1303 /* 1304 * If the page clean was interrupted, fail the invalidation. 1305 * Not doing so, we run the risk of losing dirty pages in the 1306 * vinvalbuf() call below. 1307 */ 1308 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1309 goto out; 1310 } 1311 1312 error = vinvalbuf(vp, flags, slpflag, 0); 1313 while (error) { 1314 if (intrflg && (error = newnfs_sigintr(nmp, td))) 1315 goto out; 1316 error = vinvalbuf(vp, flags, 0, slptimeo); 1317 } 1318 mtx_lock(&np->n_mtx); 1319 if (np->n_directio_asyncwr == 0) 1320 np->n_flag &= ~NMODIFIED; 1321 mtx_unlock(&np->n_mtx); 1322 out: 1323 ncl_downgrade_vnlock(vp, old_lock); 1324 return error; 1325 } 1326 1327 /* 1328 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 1329 * This is mainly to avoid queueing async I/O requests when the nfsiods 1330 * are all hung on a dead server. 1331 * 1332 * Note: ncl_asyncio() does not clear (BIO_ERROR|B_INVAL) but when the bp 1333 * is eventually dequeued by the async daemon, ncl_doio() *will*. 1334 */ 1335 int 1336 ncl_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) 1337 { 1338 int iod; 1339 int gotiod; 1340 int slpflag = 0; 1341 int slptimeo = 0; 1342 int error, error2; 1343 1344 /* 1345 * Commits are usually short and sweet so lets save some cpu and 1346 * leave the async daemons for more important rpc's (such as reads 1347 * and writes). 1348 */ 1349 mtx_lock(&ncl_iod_mutex); 1350 if (bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && 1351 (nmp->nm_bufqiods > ncl_numasync / 2)) { 1352 mtx_unlock(&ncl_iod_mutex); 1353 return(EIO); 1354 } 1355 again: 1356 if (nmp->nm_flag & NFSMNT_INT) 1357 slpflag = NFS_PCATCH; 1358 gotiod = FALSE; 1359 1360 /* 1361 * Find a free iod to process this request. 1362 */ 1363 for (iod = 0; iod < ncl_numasync; iod++) 1364 if (ncl_iodwant[iod] == NFSIOD_AVAILABLE) { 1365 gotiod = TRUE; 1366 break; 1367 } 1368 1369 /* 1370 * Try to create one if none are free. 1371 */ 1372 if (!gotiod) 1373 ncl_nfsiodnew(); 1374 else { 1375 /* 1376 * Found one, so wake it up and tell it which 1377 * mount to process. 1378 */ 1379 NFS_DPF(ASYNCIO, ("ncl_asyncio: waking iod %d for mount %p\n", 1380 iod, nmp)); 1381 ncl_iodwant[iod] = NFSIOD_NOT_AVAILABLE; 1382 ncl_iodmount[iod] = nmp; 1383 nmp->nm_bufqiods++; 1384 wakeup(&ncl_iodwant[iod]); 1385 } 1386 1387 /* 1388 * If none are free, we may already have an iod working on this mount 1389 * point. If so, it will process our request. 1390 */ 1391 if (!gotiod) { 1392 if (nmp->nm_bufqiods > 0) { 1393 NFS_DPF(ASYNCIO, 1394 ("ncl_asyncio: %d iods are already processing mount %p\n", 1395 nmp->nm_bufqiods, nmp)); 1396 gotiod = TRUE; 1397 } 1398 } 1399 1400 /* 1401 * If we have an iod which can process the request, then queue 1402 * the buffer. 1403 */ 1404 if (gotiod) { 1405 /* 1406 * Ensure that the queue never grows too large. We still want 1407 * to asynchronize so we block rather then return EIO. 1408 */ 1409 while (nmp->nm_bufqlen >= 2*ncl_numasync) { 1410 NFS_DPF(ASYNCIO, 1411 ("ncl_asyncio: waiting for mount %p queue to drain\n", nmp)); 1412 nmp->nm_bufqwant = TRUE; 1413 error = newnfs_msleep(td, &nmp->nm_bufq, 1414 &ncl_iod_mutex, slpflag | PRIBIO, "nfsaio", 1415 slptimeo); 1416 if (error) { 1417 error2 = newnfs_sigintr(nmp, td); 1418 if (error2) { 1419 mtx_unlock(&ncl_iod_mutex); 1420 return (error2); 1421 } 1422 if (slpflag == NFS_PCATCH) { 1423 slpflag = 0; 1424 slptimeo = 2 * hz; 1425 } 1426 } 1427 /* 1428 * We might have lost our iod while sleeping, 1429 * so check and loop if nescessary. 1430 */ 1431 goto again; 1432 } 1433 1434 /* We might have lost our nfsiod */ 1435 if (nmp->nm_bufqiods == 0) { 1436 NFS_DPF(ASYNCIO, 1437 ("ncl_asyncio: no iods after mount %p queue was drained, looping\n", nmp)); 1438 goto again; 1439 } 1440 1441 if (bp->b_iocmd == BIO_READ) { 1442 if (bp->b_rcred == NOCRED && cred != NOCRED) 1443 bp->b_rcred = crhold(cred); 1444 } else { 1445 if (bp->b_wcred == NOCRED && cred != NOCRED) 1446 bp->b_wcred = crhold(cred); 1447 } 1448 1449 if (bp->b_flags & B_REMFREE) 1450 bremfreef(bp); 1451 BUF_KERNPROC(bp); 1452 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 1453 nmp->nm_bufqlen++; 1454 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1455 mtx_lock(&(VTONFS(bp->b_vp))->n_mtx); 1456 VTONFS(bp->b_vp)->n_flag |= NMODIFIED; 1457 VTONFS(bp->b_vp)->n_directio_asyncwr++; 1458 mtx_unlock(&(VTONFS(bp->b_vp))->n_mtx); 1459 } 1460 mtx_unlock(&ncl_iod_mutex); 1461 return (0); 1462 } 1463 1464 mtx_unlock(&ncl_iod_mutex); 1465 1466 /* 1467 * All the iods are busy on other mounts, so return EIO to 1468 * force the caller to process the i/o synchronously. 1469 */ 1470 NFS_DPF(ASYNCIO, ("ncl_asyncio: no iods available, i/o is synchronous\n")); 1471 return (EIO); 1472 } 1473 1474 void 1475 ncl_doio_directwrite(struct buf *bp) 1476 { 1477 int iomode, must_commit; 1478 struct uio *uiop = (struct uio *)bp->b_caller1; 1479 char *iov_base = uiop->uio_iov->iov_base; 1480 1481 iomode = NFSWRITE_FILESYNC; 1482 uiop->uio_td = NULL; /* NULL since we're in nfsiod */ 1483 ncl_writerpc(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit, 0); 1484 KASSERT((must_commit == 0), ("ncl_doio_directwrite: Did not commit write")); 1485 free(iov_base, M_NFSDIRECTIO); 1486 free(uiop->uio_iov, M_NFSDIRECTIO); 1487 free(uiop, M_NFSDIRECTIO); 1488 if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { 1489 struct nfsnode *np = VTONFS(bp->b_vp); 1490 mtx_lock(&np->n_mtx); 1491 np->n_directio_asyncwr--; 1492 if (np->n_directio_asyncwr == 0) { 1493 np->n_flag &= ~NMODIFIED; 1494 if ((np->n_flag & NFSYNCWAIT)) { 1495 np->n_flag &= ~NFSYNCWAIT; 1496 wakeup((caddr_t)&np->n_directio_asyncwr); 1497 } 1498 } 1499 mtx_unlock(&np->n_mtx); 1500 } 1501 bp->b_vp = NULL; 1502 relpbuf(bp, &ncl_pbuf_freecnt); 1503 } 1504 1505 /* 1506 * Do an I/O operation to/from a cache block. This may be called 1507 * synchronously or from an nfsiod. 1508 */ 1509 int 1510 ncl_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td, 1511 int called_from_strategy) 1512 { 1513 struct uio *uiop; 1514 struct nfsnode *np; 1515 struct nfsmount *nmp; 1516 int error = 0, iomode, must_commit = 0; 1517 struct uio uio; 1518 struct iovec io; 1519 struct proc *p = td ? td->td_proc : NULL; 1520 uint8_t iocmd; 1521 1522 np = VTONFS(vp); 1523 nmp = VFSTONFS(vp->v_mount); 1524 uiop = &uio; 1525 uiop->uio_iov = &io; 1526 uiop->uio_iovcnt = 1; 1527 uiop->uio_segflg = UIO_SYSSPACE; 1528 uiop->uio_td = td; 1529 1530 /* 1531 * clear BIO_ERROR and B_INVAL state prior to initiating the I/O. We 1532 * do this here so we do not have to do it in all the code that 1533 * calls us. 1534 */ 1535 bp->b_flags &= ~B_INVAL; 1536 bp->b_ioflags &= ~BIO_ERROR; 1537 1538 KASSERT(!(bp->b_flags & B_DONE), ("ncl_doio: bp %p already marked done", bp)); 1539 iocmd = bp->b_iocmd; 1540 if (iocmd == BIO_READ) { 1541 io.iov_len = uiop->uio_resid = bp->b_bcount; 1542 io.iov_base = bp->b_data; 1543 uiop->uio_rw = UIO_READ; 1544 1545 switch (vp->v_type) { 1546 case VREG: 1547 uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE; 1548 NFSINCRGLOBAL(newnfsstats.read_bios); 1549 error = ncl_readrpc(vp, uiop, cr); 1550 1551 if (!error) { 1552 if (uiop->uio_resid) { 1553 /* 1554 * If we had a short read with no error, we must have 1555 * hit a file hole. We should zero-fill the remainder. 1556 * This can also occur if the server hits the file EOF. 1557 * 1558 * Holes used to be able to occur due to pending 1559 * writes, but that is not possible any longer. 1560 */ 1561 int nread = bp->b_bcount - uiop->uio_resid; 1562 int left = uiop->uio_resid; 1563 1564 if (left > 0) 1565 bzero((char *)bp->b_data + nread, left); 1566 uiop->uio_resid = 0; 1567 } 1568 } 1569 /* ASSERT_VOP_LOCKED(vp, "ncl_doio"); */ 1570 if (p && (vp->v_vflag & VV_TEXT)) { 1571 mtx_lock(&np->n_mtx); 1572 if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.na_mtime)) { 1573 mtx_unlock(&np->n_mtx); 1574 PROC_LOCK(p); 1575 killproc(p, "text file modification"); 1576 PROC_UNLOCK(p); 1577 } else 1578 mtx_unlock(&np->n_mtx); 1579 } 1580 break; 1581 case VLNK: 1582 uiop->uio_offset = (off_t)0; 1583 NFSINCRGLOBAL(newnfsstats.readlink_bios); 1584 error = ncl_readlinkrpc(vp, uiop, cr); 1585 break; 1586 case VDIR: 1587 NFSINCRGLOBAL(newnfsstats.readdir_bios); 1588 uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ; 1589 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) != 0) { 1590 error = ncl_readdirplusrpc(vp, uiop, cr, td); 1591 if (error == NFSERR_NOTSUPP) 1592 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 1593 } 1594 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 1595 error = ncl_readdirrpc(vp, uiop, cr, td); 1596 /* 1597 * end-of-directory sets B_INVAL but does not generate an 1598 * error. 1599 */ 1600 if (error == 0 && uiop->uio_resid == bp->b_bcount) 1601 bp->b_flags |= B_INVAL; 1602 break; 1603 default: 1604 ncl_printf("ncl_doio: type %x unexpected\n", vp->v_type); 1605 break; 1606 }; 1607 if (error) { 1608 bp->b_ioflags |= BIO_ERROR; 1609 bp->b_error = error; 1610 } 1611 } else { 1612 /* 1613 * If we only need to commit, try to commit 1614 */ 1615 if (bp->b_flags & B_NEEDCOMMIT) { 1616 int retv; 1617 off_t off; 1618 1619 off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff; 1620 retv = ncl_commit(vp, off, bp->b_dirtyend-bp->b_dirtyoff, 1621 bp->b_wcred, td); 1622 if (retv == 0) { 1623 bp->b_dirtyoff = bp->b_dirtyend = 0; 1624 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1625 bp->b_resid = 0; 1626 bufdone(bp); 1627 return (0); 1628 } 1629 if (retv == NFSERR_STALEWRITEVERF) { 1630 ncl_clearcommit(vp->v_mount); 1631 } 1632 } 1633 1634 /* 1635 * Setup for actual write 1636 */ 1637 mtx_lock(&np->n_mtx); 1638 if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size) 1639 bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE; 1640 mtx_unlock(&np->n_mtx); 1641 1642 if (bp->b_dirtyend > bp->b_dirtyoff) { 1643 io.iov_len = uiop->uio_resid = bp->b_dirtyend 1644 - bp->b_dirtyoff; 1645 uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE 1646 + bp->b_dirtyoff; 1647 io.iov_base = (char *)bp->b_data + bp->b_dirtyoff; 1648 uiop->uio_rw = UIO_WRITE; 1649 NFSINCRGLOBAL(newnfsstats.write_bios); 1650 1651 if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC) 1652 iomode = NFSWRITE_UNSTABLE; 1653 else 1654 iomode = NFSWRITE_FILESYNC; 1655 1656 error = ncl_writerpc(vp, uiop, cr, &iomode, &must_commit, 1657 called_from_strategy); 1658 1659 /* 1660 * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try 1661 * to cluster the buffers needing commit. This will allow 1662 * the system to submit a single commit rpc for the whole 1663 * cluster. We can do this even if the buffer is not 100% 1664 * dirty (relative to the NFS blocksize), so we optimize the 1665 * append-to-file-case. 1666 * 1667 * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be 1668 * cleared because write clustering only works for commit 1669 * rpc's, not for the data portion of the write). 1670 */ 1671 1672 if (!error && iomode == NFSWRITE_UNSTABLE) { 1673 bp->b_flags |= B_NEEDCOMMIT; 1674 if (bp->b_dirtyoff == 0 1675 && bp->b_dirtyend == bp->b_bcount) 1676 bp->b_flags |= B_CLUSTEROK; 1677 } else { 1678 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); 1679 } 1680 1681 /* 1682 * For an interrupted write, the buffer is still valid 1683 * and the write hasn't been pushed to the server yet, 1684 * so we can't set BIO_ERROR and report the interruption 1685 * by setting B_EINTR. For the B_ASYNC case, B_EINTR 1686 * is not relevant, so the rpc attempt is essentially 1687 * a noop. For the case of a V3 write rpc not being 1688 * committed to stable storage, the block is still 1689 * dirty and requires either a commit rpc or another 1690 * write rpc with iomode == NFSV3WRITE_FILESYNC before 1691 * the block is reused. This is indicated by setting 1692 * the B_DELWRI and B_NEEDCOMMIT flags. 1693 * 1694 * EIO is returned by ncl_writerpc() to indicate a recoverable 1695 * write error and is handled as above, except that 1696 * B_EINTR isn't set. One cause of this is a stale stateid 1697 * error for the RPC that indicates recovery is required, 1698 * when called with called_from_strategy != 0. 1699 * 1700 * If the buffer is marked B_PAGING, it does not reside on 1701 * the vp's paging queues so we cannot call bdirty(). The 1702 * bp in this case is not an NFS cache block so we should 1703 * be safe. XXX 1704 * 1705 * The logic below breaks up errors into recoverable and 1706 * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE 1707 * and keep the buffer around for potential write retries. 1708 * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) 1709 * and save the error in the nfsnode. This is less than ideal 1710 * but necessary. Keeping such buffers around could potentially 1711 * cause buffer exhaustion eventually (they can never be written 1712 * out, so will get constantly be re-dirtied). It also causes 1713 * all sorts of vfs panics. For non-recoverable write errors, 1714 * also invalidate the attrcache, so we'll be forced to go over 1715 * the wire for this object, returning an error to user on next 1716 * call (most of the time). 1717 */ 1718 if (error == EINTR || error == EIO || error == ETIMEDOUT 1719 || (!error && (bp->b_flags & B_NEEDCOMMIT))) { 1720 int s; 1721 1722 s = splbio(); 1723 bp->b_flags &= ~(B_INVAL|B_NOCACHE); 1724 if ((bp->b_flags & B_PAGING) == 0) { 1725 bdirty(bp); 1726 bp->b_flags &= ~B_DONE; 1727 } 1728 if ((error == EINTR || error == ETIMEDOUT) && 1729 (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 mtx_unlock(&np->n_mtx); 1741 } 1742 bp->b_dirtyoff = bp->b_dirtyend = 0; 1743 } 1744 } else { 1745 bp->b_resid = 0; 1746 bufdone(bp); 1747 return (0); 1748 } 1749 } 1750 bp->b_resid = uiop->uio_resid; 1751 if (must_commit) 1752 ncl_clearcommit(vp->v_mount); 1753 bufdone(bp); 1754 return (error); 1755 } 1756 1757 /* 1758 * Used to aid in handling ftruncate() operations on the NFS client side. 1759 * Truncation creates a number of special problems for NFS. We have to 1760 * throw away VM pages and buffer cache buffers that are beyond EOF, and 1761 * we have to properly handle VM pages or (potentially dirty) buffers 1762 * that straddle the truncation point. 1763 */ 1764 1765 int 1766 ncl_meta_setsize(struct vnode *vp, struct ucred *cred, struct thread *td, u_quad_t nsize) 1767 { 1768 struct nfsnode *np = VTONFS(vp); 1769 u_quad_t tsize; 1770 int biosize = vp->v_bufobj.bo_bsize; 1771 int error = 0; 1772 1773 mtx_lock(&np->n_mtx); 1774 tsize = np->n_size; 1775 np->n_size = nsize; 1776 mtx_unlock(&np->n_mtx); 1777 1778 if (nsize < tsize) { 1779 struct buf *bp; 1780 daddr_t lbn; 1781 int bufsize; 1782 1783 /* 1784 * vtruncbuf() doesn't get the buffer overlapping the 1785 * truncation point. We may have a B_DELWRI and/or B_CACHE 1786 * buffer that now needs to be truncated. 1787 */ 1788 error = vtruncbuf(vp, cred, td, nsize, biosize); 1789 lbn = nsize / biosize; 1790 bufsize = nsize & (biosize - 1); 1791 bp = nfs_getcacheblk(vp, lbn, bufsize, td); 1792 if (!bp) 1793 return EINTR; 1794 if (bp->b_dirtyoff > bp->b_bcount) 1795 bp->b_dirtyoff = bp->b_bcount; 1796 if (bp->b_dirtyend > bp->b_bcount) 1797 bp->b_dirtyend = bp->b_bcount; 1798 bp->b_flags |= B_RELBUF; /* don't leave garbage around */ 1799 brelse(bp); 1800 } else { 1801 vnode_pager_setsize(vp, nsize); 1802 } 1803 return(error); 1804 } 1805
Cache object: d6dd42c908cf1125e22f0f5c5ffef239
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