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sys/nfs/nfs_bio.c
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1 /* $NetBSD: nfs_bio.c,v 1.201 2022/06/24 16:50:00 hannken Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Rick Macklem at The University of Guelph. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)nfs_bio.c 8.9 (Berkeley) 3/30/95 35 */ 36 37 #include <sys/cdefs.h> 38 __KERNEL_RCSID(0, "$NetBSD: nfs_bio.c,v 1.201 2022/06/24 16:50:00 hannken Exp $"); 39 40 #ifdef _KERNEL_OPT 41 #include "opt_nfs.h" 42 #include "opt_ddb.h" 43 #endif 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/resourcevar.h> 48 #include <sys/signalvar.h> 49 #include <sys/proc.h> 50 #include <sys/buf.h> 51 #include <sys/vnode.h> 52 #include <sys/mount.h> 53 #include <sys/kernel.h> 54 #include <sys/namei.h> 55 #include <sys/dirent.h> 56 #include <sys/kauth.h> 57 58 #include <uvm/uvm.h> 59 #include <uvm/uvm_extern.h> 60 61 #include <nfs/rpcv2.h> 62 #include <nfs/nfsproto.h> 63 #include <nfs/nfs.h> 64 #include <nfs/nfsmount.h> 65 #include <nfs/nfsnode.h> 66 #include <nfs/nfs_var.h> 67 68 extern int nfs_numasync; 69 extern int nfs_commitsize; 70 extern struct nfsstats nfsstats; 71 72 static int nfs_doio_read(struct buf *, struct uio *); 73 static int nfs_doio_write(struct buf *, struct uio *); 74 static int nfs_doio_phys(struct buf *, struct uio *); 75 76 /* 77 * Vnode op for read using bio 78 * Any similarity to readip() is purely coincidental 79 */ 80 int 81 nfs_bioread(struct vnode *vp, struct uio *uio, int ioflag, 82 kauth_cred_t cred, int cflag) 83 { 84 struct nfsnode *np = VTONFS(vp); 85 struct buf *bp = NULL, *rabp; 86 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 87 struct nfsdircache *ndp = NULL, *nndp = NULL; 88 void *baddr; 89 int got_buf = 0, error = 0, n = 0, on = 0, en, enn; 90 int enough = 0; 91 struct dirent *dp, *pdp, *edp, *ep; 92 off_t curoff = 0; 93 int advice; 94 struct lwp *l = curlwp; 95 96 #ifdef DIAGNOSTIC 97 if (uio->uio_rw != UIO_READ) 98 panic("nfs_read mode"); 99 #endif 100 if (uio->uio_resid == 0) 101 return (0); 102 if (vp->v_type != VDIR && uio->uio_offset < 0) 103 return (EINVAL); 104 #ifndef NFS_V2_ONLY 105 if ((nmp->nm_flag & NFSMNT_NFSV3) && 106 !(nmp->nm_iflag & NFSMNT_GOTFSINFO)) 107 (void)nfs_fsinfo(nmp, vp, cred, l); 108 #endif 109 if (vp->v_type != VDIR && 110 (uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 111 return (EFBIG); 112 113 /* 114 * For nfs, cache consistency can only be maintained approximately. 115 * Although RFC1094 does not specify the criteria, the following is 116 * believed to be compatible with the reference port. 117 * 118 * If the file's modify time on the server has changed since the 119 * last read rpc or you have written to the file, 120 * you may have lost data cache consistency with the 121 * server, so flush all of the file's data out of the cache. 122 * Then force a getattr rpc to ensure that you have up to date 123 * attributes. 124 * NB: This implies that cache data can be read when up to 125 * nfs_attrtimeo seconds out of date. If you find that you need current 126 * attributes this could be forced by setting n_attrstamp to 0 before 127 * the VOP_GETATTR() call. 128 */ 129 130 if (vp->v_type != VLNK) { 131 error = nfs_flushstalebuf(vp, cred, l, 132 NFS_FLUSHSTALEBUF_MYWRITE); 133 if (error) 134 return error; 135 } 136 137 do { 138 /* 139 * Don't cache symlinks. 140 */ 141 if ((vp->v_vflag & VV_ROOT) && vp->v_type == VLNK) { 142 return (nfs_readlinkrpc(vp, uio, cred)); 143 } 144 baddr = (void *)0; 145 switch (vp->v_type) { 146 case VREG: 147 nfsstats.biocache_reads++; 148 149 advice = IO_ADV_DECODE(ioflag); 150 error = 0; 151 while (uio->uio_resid > 0) { 152 vsize_t bytelen; 153 154 nfs_delayedtruncate(vp); 155 if (np->n_size <= uio->uio_offset) { 156 break; 157 } 158 bytelen = 159 MIN(np->n_size - uio->uio_offset, uio->uio_resid); 160 error = ubc_uiomove(&vp->v_uobj, uio, bytelen, advice, 161 UBC_READ | UBC_PARTIALOK | UBC_VNODE_FLAGS(vp)); 162 if (error) { 163 /* 164 * XXXkludge 165 * the file has been truncated on the server. 166 * there isn't much we can do. 167 */ 168 if (uio->uio_offset >= np->n_size) { 169 /* end of file */ 170 error = 0; 171 } else { 172 break; 173 } 174 } 175 } 176 break; 177 178 case VLNK: 179 nfsstats.biocache_readlinks++; 180 bp = nfs_getcacheblk(vp, (daddr_t)0, MAXPATHLEN, l); 181 if (!bp) 182 return (EINTR); 183 if ((bp->b_oflags & BO_DONE) == 0) { 184 bp->b_flags |= B_READ; 185 error = nfs_doio(bp); 186 if (error) { 187 brelse(bp, 0); 188 return (error); 189 } 190 } 191 n = MIN(uio->uio_resid, MAXPATHLEN - bp->b_resid); 192 got_buf = 1; 193 on = 0; 194 break; 195 case VDIR: 196 diragain: 197 nfsstats.biocache_readdirs++; 198 ndp = nfs_searchdircache(vp, uio->uio_offset, 199 (nmp->nm_flag & NFSMNT_XLATECOOKIE), 0); 200 if (!ndp) { 201 /* 202 * We've been handed a cookie that is not 203 * in the cache. If we're not translating 204 * 32 <-> 64, it may be a value that was 205 * flushed out of the cache because it grew 206 * too big. Let the server judge if it's 207 * valid or not. In the translation case, 208 * we have no way of validating this value, 209 * so punt. 210 */ 211 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) 212 return (EINVAL); 213 ndp = nfs_enterdircache(vp, uio->uio_offset, 214 uio->uio_offset, 0, 0); 215 } 216 217 if (NFS_EOFVALID(np) && 218 ndp->dc_cookie == np->n_direofoffset) { 219 nfs_putdircache(np, ndp); 220 nfsstats.direofcache_hits++; 221 return (0); 222 } 223 224 bp = nfs_getcacheblk(vp, NFSDC_BLKNO(ndp), NFS_DIRBLKSIZ, l); 225 if (!bp) 226 return (EINTR); 227 if ((bp->b_oflags & BO_DONE) == 0) { 228 bp->b_flags |= B_READ; 229 bp->b_dcookie = ndp->dc_blkcookie; 230 error = nfs_doio(bp); 231 if (error) { 232 /* 233 * Yuck! The directory has been modified on the 234 * server. Punt and let the userland code 235 * deal with it. 236 */ 237 nfs_putdircache(np, ndp); 238 brelse(bp, 0); 239 /* 240 * nfs_request maps NFSERR_BAD_COOKIE to EINVAL. 241 */ 242 if (error == EINVAL) { /* NFSERR_BAD_COOKIE */ 243 nfs_invaldircache(vp, 0); 244 nfs_vinvalbuf(vp, 0, cred, l, 1); 245 } 246 return (error); 247 } 248 } 249 250 /* 251 * Just return if we hit EOF right away with this 252 * block. Always check here, because direofoffset 253 * may have been set by an nfsiod since the last 254 * check. 255 * 256 * also, empty block implies EOF. 257 */ 258 259 if (bp->b_bcount == bp->b_resid || 260 (NFS_EOFVALID(np) && 261 ndp->dc_blkcookie == np->n_direofoffset)) { 262 KASSERT(bp->b_bcount != bp->b_resid || 263 ndp->dc_blkcookie == bp->b_dcookie); 264 nfs_putdircache(np, ndp); 265 brelse(bp, BC_NOCACHE); 266 return 0; 267 } 268 269 /* 270 * Find the entry we were looking for in the block. 271 */ 272 273 en = ndp->dc_entry; 274 275 pdp = dp = (struct dirent *)bp->b_data; 276 edp = (struct dirent *)(void *)((char *)bp->b_data + bp->b_bcount - 277 bp->b_resid); 278 enn = 0; 279 while (enn < en && dp < edp) { 280 pdp = dp; 281 dp = _DIRENT_NEXT(dp); 282 enn++; 283 } 284 285 /* 286 * If the entry number was bigger than the number of 287 * entries in the block, or the cookie of the previous 288 * entry doesn't match, the directory cache is 289 * stale. Flush it and try again (i.e. go to 290 * the server). 291 */ 292 if (dp >= edp || (struct dirent *)_DIRENT_NEXT(dp) > edp || 293 (en > 0 && NFS_GETCOOKIE(pdp) != ndp->dc_cookie)) { 294 #ifdef DEBUG 295 printf("invalid cache: %p %p %p off %jx %jx\n", 296 pdp, dp, edp, 297 (uintmax_t)uio->uio_offset, 298 (uintmax_t)NFS_GETCOOKIE(pdp)); 299 #endif 300 nfs_putdircache(np, ndp); 301 brelse(bp, 0); 302 nfs_invaldircache(vp, 0); 303 nfs_vinvalbuf(vp, 0, cred, l, 0); 304 goto diragain; 305 } 306 307 on = (char *)dp - (char *)bp->b_data; 308 309 /* 310 * Cache all entries that may be exported to the 311 * user, as they may be thrown back at us. The 312 * NFSBIO_CACHECOOKIES flag indicates that all 313 * entries are being 'exported', so cache them all. 314 */ 315 316 if (en == 0 && pdp == dp) { 317 dp = _DIRENT_NEXT(dp); 318 enn++; 319 } 320 321 if (uio->uio_resid < (bp->b_bcount - bp->b_resid - on)) { 322 n = uio->uio_resid; 323 enough = 1; 324 } else 325 n = bp->b_bcount - bp->b_resid - on; 326 327 ep = (struct dirent *)(void *)((char *)bp->b_data + on + n); 328 329 /* 330 * Find last complete entry to copy, caching entries 331 * (if requested) as we go. 332 */ 333 334 while (dp < ep && (struct dirent *)_DIRENT_NEXT(dp) <= ep) { 335 if (cflag & NFSBIO_CACHECOOKIES) { 336 nndp = nfs_enterdircache(vp, NFS_GETCOOKIE(pdp), 337 ndp->dc_blkcookie, enn, bp->b_lblkno); 338 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 339 NFS_STASHCOOKIE32(pdp, 340 nndp->dc_cookie32); 341 } 342 nfs_putdircache(np, nndp); 343 } 344 pdp = dp; 345 dp = _DIRENT_NEXT(dp); 346 enn++; 347 } 348 nfs_putdircache(np, ndp); 349 350 /* 351 * If the last requested entry was not the last in the 352 * buffer (happens if NFS_DIRFRAGSIZ < NFS_DIRBLKSIZ), 353 * cache the cookie of the last requested one, and 354 * set of the offset to it. 355 */ 356 357 if ((on + n) < bp->b_bcount - bp->b_resid) { 358 curoff = NFS_GETCOOKIE(pdp); 359 nndp = nfs_enterdircache(vp, curoff, ndp->dc_blkcookie, 360 enn, bp->b_lblkno); 361 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 362 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32); 363 curoff = nndp->dc_cookie32; 364 } 365 nfs_putdircache(np, nndp); 366 } else 367 curoff = bp->b_dcookie; 368 369 /* 370 * Always cache the entry for the next block, 371 * so that readaheads can use it. 372 */ 373 nndp = nfs_enterdircache(vp, bp->b_dcookie, bp->b_dcookie, 0,0); 374 if (nmp->nm_flag & NFSMNT_XLATECOOKIE) { 375 if (curoff == bp->b_dcookie) { 376 NFS_STASHCOOKIE32(pdp, nndp->dc_cookie32); 377 curoff = nndp->dc_cookie32; 378 } 379 } 380 381 n = (char *)_DIRENT_NEXT(pdp) - ((char *)bp->b_data + on); 382 383 /* 384 * If not eof and read aheads are enabled, start one. 385 * (You need the current block first, so that you have the 386 * directory offset cookie of the next block.) 387 */ 388 if (nfs_numasync > 0 && nmp->nm_readahead > 0 && 389 !NFS_EOFVALID(np)) { 390 rabp = nfs_getcacheblk(vp, NFSDC_BLKNO(nndp), 391 NFS_DIRBLKSIZ, l); 392 if (rabp) { 393 if ((rabp->b_oflags & (BO_DONE | BO_DELWRI)) == 0) { 394 rabp->b_dcookie = nndp->dc_cookie; 395 rabp->b_flags |= (B_READ | B_ASYNC); 396 if (nfs_asyncio(rabp)) { 397 brelse(rabp, BC_INVAL); 398 } 399 } else 400 brelse(rabp, 0); 401 } 402 } 403 nfs_putdircache(np, nndp); 404 got_buf = 1; 405 break; 406 default: 407 printf(" nfsbioread: type %x unexpected\n",vp->v_type); 408 break; 409 } 410 411 if (n > 0) { 412 if (!baddr) 413 baddr = bp->b_data; 414 error = uiomove((char *)baddr + on, (int)n, uio); 415 } 416 switch (vp->v_type) { 417 case VREG: 418 break; 419 case VLNK: 420 n = 0; 421 break; 422 case VDIR: 423 uio->uio_offset = curoff; 424 if (enough) 425 n = 0; 426 break; 427 default: 428 printf(" nfsbioread: type %x unexpected\n",vp->v_type); 429 } 430 if (got_buf) 431 brelse(bp, 0); 432 } while (error == 0 && uio->uio_resid > 0 && n > 0); 433 return (error); 434 } 435 436 /* 437 * Vnode op for write using bio 438 */ 439 int 440 nfs_write(void *v) 441 { 442 struct vop_write_args /* { 443 struct vnode *a_vp; 444 struct uio *a_uio; 445 int a_ioflag; 446 kauth_cred_t a_cred; 447 } */ *ap = v; 448 struct uio *uio = ap->a_uio; 449 struct lwp *l = curlwp; 450 struct vnode *vp = ap->a_vp; 451 struct nfsnode *np = VTONFS(vp); 452 kauth_cred_t cred = ap->a_cred; 453 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 454 voff_t oldoff, origoff; 455 vsize_t bytelen; 456 int error = 0; 457 int ioflag = ap->a_ioflag; 458 459 #ifdef DIAGNOSTIC 460 if (uio->uio_rw != UIO_WRITE) 461 panic("nfs_write mode"); 462 #endif 463 if (vp->v_type != VREG) 464 return (EIO); 465 if (np->n_flag & NWRITEERR) { 466 np->n_flag &= ~NWRITEERR; 467 return (np->n_error); 468 } 469 #ifndef NFS_V2_ONLY 470 if ((nmp->nm_flag & NFSMNT_NFSV3) && 471 !(nmp->nm_iflag & NFSMNT_GOTFSINFO)) 472 (void)nfs_fsinfo(nmp, vp, cred, l); 473 #endif 474 if (ioflag & IO_APPEND) { 475 NFS_INVALIDATE_ATTRCACHE(np); 476 error = nfs_flushstalebuf(vp, cred, l, 477 NFS_FLUSHSTALEBUF_MYWRITE); 478 if (error) 479 return (error); 480 uio->uio_offset = np->n_size; 481 482 /* 483 * This is already checked above VOP_WRITE, but recheck 484 * the append case here to make sure our idea of the 485 * file size is as fresh as possible. 486 */ 487 if (uio->uio_offset + uio->uio_resid > 488 l->l_proc->p_rlimit[RLIMIT_FSIZE].rlim_cur) { 489 mutex_enter(&proc_lock); 490 psignal(l->l_proc, SIGXFSZ); 491 mutex_exit(&proc_lock); 492 return (EFBIG); 493 } 494 } 495 if (uio->uio_offset < 0) 496 return (EINVAL); 497 if ((uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize) 498 return (EFBIG); 499 if (uio->uio_resid == 0) 500 return (0); 501 502 origoff = uio->uio_offset; 503 do { 504 bool overwrite; /* if we are overwriting whole pages */ 505 u_quad_t oldsize; 506 oldoff = uio->uio_offset; 507 bytelen = uio->uio_resid; 508 509 nfsstats.biocache_writes++; 510 511 oldsize = np->n_size; 512 np->n_flag |= NMODIFIED; 513 if (np->n_size < uio->uio_offset + bytelen) { 514 np->n_size = uio->uio_offset + bytelen; 515 } 516 overwrite = false; 517 if ((uio->uio_offset & PAGE_MASK) == 0) { 518 if ((vp->v_vflag & VV_MAPPED) == 0 && 519 bytelen > PAGE_SIZE) { 520 bytelen = trunc_page(bytelen); 521 overwrite = true; 522 } else if ((bytelen & PAGE_MASK) == 0 && 523 uio->uio_offset >= vp->v_size) { 524 overwrite = true; 525 } 526 } 527 if (vp->v_size < uio->uio_offset + bytelen) { 528 uvm_vnp_setwritesize(vp, uio->uio_offset + bytelen); 529 } 530 error = ubc_uiomove(&vp->v_uobj, uio, bytelen, 531 UVM_ADV_RANDOM, UBC_WRITE | UBC_PARTIALOK | 532 (overwrite ? UBC_FAULTBUSY : 0) | 533 UBC_VNODE_FLAGS(vp)); 534 if (error) { 535 uvm_vnp_setwritesize(vp, vp->v_size); 536 if (overwrite && np->n_size != oldsize) { 537 /* 538 * backout size and free pages past eof. 539 */ 540 np->n_size = oldsize; 541 rw_enter(vp->v_uobj.vmobjlock, RW_WRITER); 542 (void)VOP_PUTPAGES(vp, round_page(vp->v_size), 543 0, PGO_SYNCIO | PGO_FREE); 544 } 545 break; 546 } 547 548 /* 549 * update UVM's notion of the size now that we've 550 * copied the data into the vnode's pages. 551 */ 552 553 if (vp->v_size < uio->uio_offset) { 554 uvm_vnp_setsize(vp, uio->uio_offset); 555 } 556 557 if ((oldoff & ~(nmp->nm_wsize - 1)) != 558 (uio->uio_offset & ~(nmp->nm_wsize - 1))) { 559 rw_enter(vp->v_uobj.vmobjlock, RW_WRITER); 560 error = VOP_PUTPAGES(vp, 561 trunc_page(oldoff & ~(nmp->nm_wsize - 1)), 562 round_page((uio->uio_offset + nmp->nm_wsize - 1) & 563 ~(nmp->nm_wsize - 1)), PGO_CLEANIT); 564 } 565 } while (uio->uio_resid > 0); 566 if (error == 0 && (ioflag & IO_SYNC) != 0) { 567 rw_enter(vp->v_uobj.vmobjlock, RW_WRITER); 568 error = VOP_PUTPAGES(vp, 569 trunc_page(origoff & ~(nmp->nm_wsize - 1)), 570 round_page((uio->uio_offset + nmp->nm_wsize - 1) & 571 ~(nmp->nm_wsize - 1)), 572 PGO_CLEANIT | PGO_SYNCIO); 573 } 574 return error; 575 } 576 577 /* 578 * Get an nfs cache block. 579 * Allocate a new one if the block isn't currently in the cache 580 * and return the block marked busy. If the calling process is 581 * interrupted by a signal for an interruptible mount point, return 582 * NULL. 583 */ 584 struct buf * 585 nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct lwp *l) 586 { 587 struct buf *bp; 588 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 589 590 if (nmp->nm_flag & NFSMNT_INT) { 591 bp = getblk(vp, bn, size, PCATCH, 0); 592 while (bp == NULL) { 593 if (nfs_sigintr(nmp, NULL, l)) 594 return (NULL); 595 bp = getblk(vp, bn, size, 0, 2 * hz); 596 } 597 } else 598 bp = getblk(vp, bn, size, 0, 0); 599 return (bp); 600 } 601 602 /* 603 * Flush and invalidate all dirty buffers. If another process is already 604 * doing the flush, just wait for completion. 605 */ 606 int 607 nfs_vinvalbuf(struct vnode *vp, int flags, kauth_cred_t cred, 608 struct lwp *l, int intrflg) 609 { 610 struct nfsnode *np = VTONFS(vp); 611 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 612 int error = 0, allerror = 0, slptimeo; 613 bool catch_p; 614 615 if ((nmp->nm_flag & NFSMNT_INT) == 0) 616 intrflg = 0; 617 if (intrflg) { 618 catch_p = true; 619 slptimeo = 2 * hz; 620 } else { 621 catch_p = false; 622 if (nmp->nm_flag & NFSMNT_SOFT) 623 slptimeo = nmp->nm_retry * nmp->nm_timeo; 624 else 625 slptimeo = 0; 626 } 627 /* 628 * First wait for any other process doing a flush to complete. 629 */ 630 mutex_enter(vp->v_interlock); 631 while (np->n_flag & NFLUSHINPROG) { 632 np->n_flag |= NFLUSHWANT; 633 error = mtsleep(&np->n_flag, PRIBIO + 2, "nfsvinval", 634 slptimeo, vp->v_interlock); 635 if (error && intrflg && nfs_sigintr(nmp, NULL, l)) { 636 mutex_exit(vp->v_interlock); 637 return EINTR; 638 } 639 } 640 641 /* 642 * Now, flush as required. 643 */ 644 np->n_flag |= NFLUSHINPROG; 645 mutex_exit(vp->v_interlock); 646 error = vinvalbuf(vp, flags, cred, l, catch_p, 0); 647 while (error) { 648 if (allerror == 0) 649 allerror = error; 650 if (intrflg && nfs_sigintr(nmp, NULL, l)) { 651 error = EINTR; 652 break; 653 } 654 error = vinvalbuf(vp, flags, cred, l, 0, slptimeo); 655 } 656 mutex_enter(vp->v_interlock); 657 if (allerror != 0) { 658 /* 659 * Keep error from vinvalbuf so fsync/close will know. 660 */ 661 np->n_error = allerror; 662 np->n_flag |= NWRITEERR; 663 } 664 if (error == 0) 665 np->n_flag &= ~NMODIFIED; 666 np->n_flag &= ~NFLUSHINPROG; 667 if (np->n_flag & NFLUSHWANT) { 668 np->n_flag &= ~NFLUSHWANT; 669 wakeup(&np->n_flag); 670 } 671 mutex_exit(vp->v_interlock); 672 return error; 673 } 674 675 /* 676 * nfs_flushstalebuf: flush cache if it's stale. 677 * 678 * => caller shouldn't own any pages or buffers which belong to the vnode. 679 */ 680 681 int 682 nfs_flushstalebuf(struct vnode *vp, kauth_cred_t cred, struct lwp *l, 683 int flags) 684 { 685 struct nfsnode *np = VTONFS(vp); 686 struct vattr vattr; 687 int error; 688 689 if (np->n_flag & NMODIFIED) { 690 if ((flags & NFS_FLUSHSTALEBUF_MYWRITE) == 0 691 || vp->v_type != VREG) { 692 error = nfs_vinvalbuf(vp, V_SAVE, cred, l, 1); 693 if (error) 694 return error; 695 if (vp->v_type == VDIR) { 696 nfs_invaldircache(vp, 0); 697 } 698 } else { 699 /* 700 * XXX assuming writes are ours. 701 */ 702 } 703 NFS_INVALIDATE_ATTRCACHE(np); 704 error = VOP_GETATTR(vp, &vattr, cred); 705 if (error) 706 return error; 707 np->n_mtime = vattr.va_mtime; 708 } else { 709 error = VOP_GETATTR(vp, &vattr, cred); 710 if (error) 711 return error; 712 if (timespeccmp(&np->n_mtime, &vattr.va_mtime, !=)) { 713 if (vp->v_type == VDIR) { 714 nfs_invaldircache(vp, 0); 715 } 716 error = nfs_vinvalbuf(vp, V_SAVE, cred, l, 1); 717 if (error) 718 return error; 719 np->n_mtime = vattr.va_mtime; 720 } 721 } 722 723 return error; 724 } 725 726 /* 727 * Initiate asynchronous I/O. Return an error if no nfsiods are available. 728 * This is mainly to avoid queueing async I/O requests when the nfsiods 729 * are all hung on a dead server. 730 */ 731 732 int 733 nfs_asyncio(struct buf *bp) 734 { 735 struct nfs_iod *iod; 736 struct nfsmount *nmp; 737 int slptimeo = 0, error; 738 bool catch_p = false; 739 740 if (nfs_numasync == 0) 741 return (EIO); 742 743 nmp = VFSTONFS(bp->b_vp->v_mount); 744 745 if (nmp->nm_flag & NFSMNT_SOFT) 746 slptimeo = nmp->nm_retry * nmp->nm_timeo; 747 748 if (nmp->nm_iflag & NFSMNT_DISMNTFORCE) 749 slptimeo = hz; 750 751 again: 752 if (nmp->nm_flag & NFSMNT_INT) 753 catch_p = true; 754 755 /* 756 * Find a free iod to process this request. 757 */ 758 759 mutex_enter(&nfs_iodlist_lock); 760 iod = LIST_FIRST(&nfs_iodlist_idle); 761 if (iod) { 762 /* 763 * Found one, so wake it up and tell it which 764 * mount to process. 765 */ 766 LIST_REMOVE(iod, nid_idle); 767 mutex_enter(&iod->nid_lock); 768 mutex_exit(&nfs_iodlist_lock); 769 KASSERT(iod->nid_mount == NULL); 770 iod->nid_mount = nmp; 771 cv_signal(&iod->nid_cv); 772 mutex_enter(&nmp->nm_lock); 773 mutex_exit(&iod->nid_lock); 774 nmp->nm_bufqiods++; 775 if (nmp->nm_bufqlen < 2 * nmp->nm_bufqiods) { 776 cv_broadcast(&nmp->nm_aiocv); 777 } 778 } else { 779 mutex_exit(&nfs_iodlist_lock); 780 mutex_enter(&nmp->nm_lock); 781 } 782 783 KASSERT(mutex_owned(&nmp->nm_lock)); 784 785 /* 786 * If we have an iod which can process the request, then queue 787 * the buffer. However, even if we have an iod, do not initiate 788 * queue cleaning if curproc is the pageout daemon. if the NFS mount 789 * is via local loopback, we may put curproc (pagedaemon) to sleep 790 * waiting for the writes to complete. But the server (ourself) 791 * may block the write, waiting for its (ie., our) pagedaemon 792 * to produce clean pages to handle the write: deadlock. 793 * XXX: start non-loopback mounts straight away? If "lots free", 794 * let pagedaemon start loopback writes anyway? 795 */ 796 if (nmp->nm_bufqiods > 0) { 797 798 /* 799 * Ensure that the queue never grows too large. 800 */ 801 if (curlwp == uvm.pagedaemon_lwp) { 802 /* Enque for later, to avoid free-page deadlock */ 803 } else while (nmp->nm_bufqlen >= 2 * nmp->nm_bufqiods) { 804 if (catch_p) { 805 error = cv_timedwait_sig(&nmp->nm_aiocv, 806 &nmp->nm_lock, slptimeo); 807 } else { 808 error = cv_timedwait(&nmp->nm_aiocv, 809 &nmp->nm_lock, slptimeo); 810 } 811 if (error) { 812 if (error == EWOULDBLOCK && 813 nmp->nm_flag & NFSMNT_SOFT) { 814 mutex_exit(&nmp->nm_lock); 815 bp->b_error = EIO; 816 return (EIO); 817 } 818 819 if (nfs_sigintr(nmp, NULL, curlwp)) { 820 mutex_exit(&nmp->nm_lock); 821 return (EINTR); 822 } 823 if (catch_p) { 824 catch_p = false; 825 slptimeo = 2 * hz; 826 } 827 } 828 829 /* 830 * We might have lost our iod while sleeping, 831 * so check and loop if necessary. 832 */ 833 834 if (nmp->nm_bufqiods == 0) { 835 mutex_exit(&nmp->nm_lock); 836 goto again; 837 } 838 } 839 TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); 840 nmp->nm_bufqlen++; 841 mutex_exit(&nmp->nm_lock); 842 return (0); 843 } 844 mutex_exit(&nmp->nm_lock); 845 846 /* 847 * All the iods are busy on other mounts, so return EIO to 848 * force the caller to process the i/o synchronously. 849 */ 850 851 return (EIO); 852 } 853 854 /* 855 * nfs_doio for read. 856 */ 857 static int 858 nfs_doio_read(struct buf *bp, struct uio *uiop) 859 { 860 struct vnode *vp = bp->b_vp; 861 struct nfsnode *np = VTONFS(vp); 862 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 863 int error = 0; 864 865 uiop->uio_rw = UIO_READ; 866 switch (vp->v_type) { 867 case VREG: 868 nfsstats.read_bios++; 869 error = nfs_readrpc(vp, uiop); 870 if (!error && uiop->uio_resid) { 871 int diff, len; 872 873 /* 874 * If uio_resid > 0, there is a hole in the file and 875 * no writes after the hole have been pushed to 876 * the server yet or the file has been truncated 877 * on the server. 878 * Just zero fill the rest of the valid area. 879 */ 880 881 diff = bp->b_bcount - uiop->uio_resid; 882 len = uiop->uio_resid; 883 memset((char *)bp->b_data + diff, 0, len); 884 uiop->uio_resid = 0; 885 } 886 #if 0 887 if (uiop->uio_lwp && (vp->v_iflag & VI_TEXT) && 888 timespeccmp(&np->n_mtime, &np->n_vattr->va_mtime, !=)) { 889 mutex_enter(&proc_lock); 890 killproc(uiop->uio_lwp->l_proc, "process text file was modified"); 891 mutex_exit(&proc_lock); 892 #if 0 /* XXX NJWLWP */ 893 uiop->uio_lwp->l_proc->p_holdcnt++; 894 #endif 895 } 896 #endif 897 break; 898 case VLNK: 899 KASSERT(uiop->uio_offset == (off_t)0); 900 nfsstats.readlink_bios++; 901 error = nfs_readlinkrpc(vp, uiop, np->n_rcred); 902 break; 903 case VDIR: 904 nfsstats.readdir_bios++; 905 uiop->uio_offset = bp->b_dcookie; 906 #ifndef NFS_V2_ONLY 907 if (nmp->nm_flag & NFSMNT_RDIRPLUS) { 908 error = nfs_readdirplusrpc(vp, uiop, 909 curlwp->l_cred); 910 /* 911 * nfs_request maps NFSERR_NOTSUPP to ENOTSUP. 912 */ 913 if (error == ENOTSUP) 914 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 915 } 916 #else 917 nmp->nm_flag &= ~NFSMNT_RDIRPLUS; 918 #endif 919 if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0) 920 error = nfs_readdirrpc(vp, uiop, 921 curlwp->l_cred); 922 if (!error) { 923 bp->b_dcookie = uiop->uio_offset; 924 } 925 break; 926 default: 927 printf("nfs_doio: type %x unexpected\n", vp->v_type); 928 break; 929 } 930 bp->b_error = error; 931 return error; 932 } 933 934 /* 935 * nfs_doio for write. 936 */ 937 static int 938 nfs_doio_write(struct buf *bp, struct uio *uiop) 939 { 940 struct vnode *vp = bp->b_vp; 941 struct nfsnode *np = VTONFS(vp); 942 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 943 int iomode; 944 bool stalewriteverf = false; 945 int i, npages = (bp->b_bcount + PAGE_SIZE - 1) >> PAGE_SHIFT; 946 struct vm_page **pgs, *spgs[UBC_MAX_PAGES]; 947 #ifndef NFS_V2_ONLY 948 bool needcommit = true; /* need only COMMIT RPC */ 949 #else 950 bool needcommit = false; /* need only COMMIT RPC */ 951 #endif 952 bool pageprotected; 953 struct uvm_object *uobj = &vp->v_uobj; 954 int error; 955 off_t off, cnt; 956 957 if (npages < __arraycount(spgs)) 958 pgs = spgs; 959 else { 960 if ((pgs = kmem_alloc(sizeof(*pgs) * npages, KM_NOSLEEP)) == 961 NULL) 962 return ENOMEM; 963 } 964 965 if ((bp->b_flags & B_ASYNC) != 0 && NFS_ISV3(vp)) { 966 iomode = NFSV3WRITE_UNSTABLE; 967 } else { 968 iomode = NFSV3WRITE_FILESYNC; 969 } 970 971 #ifndef NFS_V2_ONLY 972 again: 973 #endif 974 rw_enter(&nmp->nm_writeverflock, RW_READER); 975 976 for (i = 0; i < npages; i++) { 977 pgs[i] = uvm_pageratop((vaddr_t)bp->b_data + (i << PAGE_SHIFT)); 978 if (pgs[i]->uobject == uobj && 979 pgs[i]->offset == uiop->uio_offset + (i << PAGE_SHIFT)) { 980 KASSERT(pgs[i]->flags & PG_BUSY); 981 /* 982 * this page belongs to our object. 983 */ 984 rw_enter(uobj->vmobjlock, RW_WRITER); 985 /* 986 * write out the page stably if it's about to 987 * be released because we can't resend it 988 * on the server crash. 989 * 990 * XXX assuming PG_RELEASE|PG_PAGEOUT won't be 991 * changed until unbusy the page. 992 */ 993 if (pgs[i]->flags & (PG_RELEASED|PG_PAGEOUT)) 994 iomode = NFSV3WRITE_FILESYNC; 995 /* 996 * if we met a page which hasn't been sent yet, 997 * we need do WRITE RPC. 998 */ 999 if ((pgs[i]->flags & PG_NEEDCOMMIT) == 0) 1000 needcommit = false; 1001 rw_exit(uobj->vmobjlock); 1002 } else { 1003 iomode = NFSV3WRITE_FILESYNC; 1004 needcommit = false; 1005 } 1006 } 1007 if (!needcommit && iomode == NFSV3WRITE_UNSTABLE) { 1008 rw_enter(uobj->vmobjlock, RW_WRITER); 1009 for (i = 0; i < npages; i++) { 1010 pgs[i]->flags |= PG_NEEDCOMMIT | PG_RDONLY; 1011 pmap_page_protect(pgs[i], VM_PROT_READ); 1012 } 1013 rw_exit(uobj->vmobjlock); 1014 pageprotected = true; /* pages can't be modified during i/o. */ 1015 } else 1016 pageprotected = false; 1017 1018 /* 1019 * Send the data to the server if necessary, 1020 * otherwise just send a commit rpc. 1021 */ 1022 #ifndef NFS_V2_ONLY 1023 if (needcommit) { 1024 1025 /* 1026 * If the buffer is in the range that we already committed, 1027 * there's nothing to do. 1028 * 1029 * If it's in the range that we need to commit, push the 1030 * whole range at once, otherwise only push the buffer. 1031 * In both these cases, acquire the commit lock to avoid 1032 * other processes modifying the range. 1033 */ 1034 1035 off = uiop->uio_offset; 1036 cnt = bp->b_bcount; 1037 mutex_enter(&np->n_commitlock); 1038 if (!nfs_in_committed_range(vp, off, bp->b_bcount)) { 1039 bool pushedrange; 1040 if (nfs_in_tobecommitted_range(vp, off, bp->b_bcount)) { 1041 pushedrange = true; 1042 off = np->n_pushlo; 1043 cnt = np->n_pushhi - np->n_pushlo; 1044 } else { 1045 pushedrange = false; 1046 } 1047 error = nfs_commit(vp, off, cnt, curlwp); 1048 if (error == 0) { 1049 if (pushedrange) { 1050 nfs_merge_commit_ranges(vp); 1051 } else { 1052 nfs_add_committed_range(vp, off, cnt); 1053 } 1054 } 1055 } else { 1056 error = 0; 1057 } 1058 mutex_exit(&np->n_commitlock); 1059 rw_exit(&nmp->nm_writeverflock); 1060 if (!error) { 1061 /* 1062 * pages are now on stable storage. 1063 */ 1064 uiop->uio_resid = 0; 1065 rw_enter(uobj->vmobjlock, RW_WRITER); 1066 for (i = 0; i < npages; i++) { 1067 pgs[i]->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY); 1068 } 1069 rw_exit(uobj->vmobjlock); 1070 goto out; 1071 } else if (error == NFSERR_STALEWRITEVERF) { 1072 nfs_clearcommit(vp->v_mount); 1073 goto again; 1074 } 1075 if (error) { 1076 bp->b_error = np->n_error = error; 1077 np->n_flag |= NWRITEERR; 1078 } 1079 goto out; 1080 } 1081 #endif 1082 off = uiop->uio_offset; 1083 cnt = bp->b_bcount; 1084 uiop->uio_rw = UIO_WRITE; 1085 nfsstats.write_bios++; 1086 error = nfs_writerpc(vp, uiop, &iomode, pageprotected, &stalewriteverf); 1087 #ifndef NFS_V2_ONLY 1088 if (!error && iomode == NFSV3WRITE_UNSTABLE) { 1089 /* 1090 * we need to commit pages later. 1091 */ 1092 mutex_enter(&np->n_commitlock); 1093 nfs_add_tobecommitted_range(vp, off, cnt); 1094 /* 1095 * if there can be too many uncommitted pages, commit them now. 1096 */ 1097 if (np->n_pushhi - np->n_pushlo > nfs_commitsize) { 1098 off = np->n_pushlo; 1099 cnt = nfs_commitsize >> 1; 1100 error = nfs_commit(vp, off, cnt, curlwp); 1101 if (!error) { 1102 nfs_add_committed_range(vp, off, cnt); 1103 nfs_del_tobecommitted_range(vp, off, cnt); 1104 } 1105 if (error == NFSERR_STALEWRITEVERF) { 1106 stalewriteverf = true; 1107 error = 0; /* it isn't a real error */ 1108 } 1109 } else { 1110 /* 1111 * re-dirty pages so that they will be passed 1112 * to us later again. 1113 */ 1114 rw_enter(uobj->vmobjlock, RW_WRITER); 1115 for (i = 0; i < npages; i++) { 1116 uvm_pagemarkdirty(pgs[i], 1117 UVM_PAGE_STATUS_DIRTY); 1118 } 1119 rw_exit(uobj->vmobjlock); 1120 } 1121 mutex_exit(&np->n_commitlock); 1122 } else 1123 #endif 1124 if (!error) { 1125 /* 1126 * pages are now on stable storage. 1127 */ 1128 mutex_enter(&np->n_commitlock); 1129 nfs_del_committed_range(vp, off, cnt); 1130 mutex_exit(&np->n_commitlock); 1131 rw_enter(uobj->vmobjlock, RW_WRITER); 1132 for (i = 0; i < npages; i++) { 1133 pgs[i]->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY); 1134 } 1135 rw_exit(uobj->vmobjlock); 1136 } else { 1137 /* 1138 * we got an error. 1139 */ 1140 bp->b_error = np->n_error = error; 1141 np->n_flag |= NWRITEERR; 1142 } 1143 1144 rw_exit(&nmp->nm_writeverflock); 1145 1146 1147 if (stalewriteverf) { 1148 nfs_clearcommit(vp->v_mount); 1149 } 1150 #ifndef NFS_V2_ONLY 1151 out: 1152 #endif 1153 if (pgs != spgs) 1154 kmem_free(pgs, sizeof(*pgs) * npages); 1155 return error; 1156 } 1157 1158 /* 1159 * nfs_doio for B_PHYS. 1160 */ 1161 static int 1162 nfs_doio_phys(struct buf *bp, struct uio *uiop) 1163 { 1164 struct vnode *vp = bp->b_vp; 1165 int error; 1166 1167 uiop->uio_offset = ((off_t)bp->b_blkno) << DEV_BSHIFT; 1168 if (bp->b_flags & B_READ) { 1169 uiop->uio_rw = UIO_READ; 1170 nfsstats.read_physios++; 1171 error = nfs_readrpc(vp, uiop); 1172 } else { 1173 int iomode = NFSV3WRITE_DATASYNC; 1174 bool stalewriteverf; 1175 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 1176 1177 uiop->uio_rw = UIO_WRITE; 1178 nfsstats.write_physios++; 1179 rw_enter(&nmp->nm_writeverflock, RW_READER); 1180 error = nfs_writerpc(vp, uiop, &iomode, false, &stalewriteverf); 1181 rw_exit(&nmp->nm_writeverflock); 1182 if (stalewriteverf) { 1183 nfs_clearcommit(bp->b_vp->v_mount); 1184 } 1185 } 1186 bp->b_error = error; 1187 return error; 1188 } 1189 1190 /* 1191 * Do an I/O operation to/from a cache block. This may be called 1192 * synchronously or from an nfsiod. 1193 */ 1194 int 1195 nfs_doio(struct buf *bp) 1196 { 1197 int error; 1198 struct uio uio; 1199 struct uio *uiop = &uio; 1200 struct iovec io; 1201 UVMHIST_FUNC("nfs_doio"); UVMHIST_CALLED(ubchist); 1202 1203 uiop->uio_iov = &io; 1204 uiop->uio_iovcnt = 1; 1205 uiop->uio_offset = (((off_t)bp->b_blkno) << DEV_BSHIFT); 1206 UIO_SETUP_SYSSPACE(uiop); 1207 io.iov_base = bp->b_data; 1208 io.iov_len = uiop->uio_resid = bp->b_bcount; 1209 1210 /* 1211 * Historically, paging was done with physio, but no more... 1212 */ 1213 if (bp->b_flags & B_PHYS) { 1214 /* 1215 * ...though reading /dev/drum still gets us here. 1216 */ 1217 error = nfs_doio_phys(bp, uiop); 1218 } else if (bp->b_flags & B_READ) { 1219 error = nfs_doio_read(bp, uiop); 1220 } else { 1221 error = nfs_doio_write(bp, uiop); 1222 } 1223 bp->b_resid = uiop->uio_resid; 1224 biodone(bp); 1225 return (error); 1226 } 1227 1228 /* 1229 * Vnode op for VM getpages. 1230 */ 1231 1232 int 1233 nfs_getpages(void *v) 1234 { 1235 struct vop_getpages_args /* { 1236 struct vnode *a_vp; 1237 voff_t a_offset; 1238 struct vm_page **a_m; 1239 int *a_count; 1240 int a_centeridx; 1241 vm_prot_t a_access_type; 1242 int a_advice; 1243 int a_flags; 1244 } */ *ap = v; 1245 1246 struct vnode *vp = ap->a_vp; 1247 struct uvm_object *uobj = &vp->v_uobj; 1248 struct nfsnode *np = VTONFS(vp); 1249 const int npages = *ap->a_count; 1250 struct vm_page *pg, **pgs, **opgs, *spgs[UBC_MAX_PAGES]; 1251 off_t origoffset, len; 1252 int i, error; 1253 bool v3 = NFS_ISV3(vp); 1254 bool write = (ap->a_access_type & VM_PROT_WRITE) != 0; 1255 bool locked = (ap->a_flags & PGO_LOCKED) != 0; 1256 1257 /* 1258 * XXX NFS wants to modify the pages below and that can't be done 1259 * with a read lock. We can't upgrade the lock here because it 1260 * would screw up UVM fault processing. Have NFS take the I/O 1261 * path. 1262 */ 1263 if (locked && rw_lock_op(uobj->vmobjlock) == RW_READER) { 1264 *ap->a_count = 0; 1265 ap->a_m[ap->a_centeridx] = NULL; 1266 return EBUSY; 1267 } 1268 1269 /* 1270 * If we are not locked we are not really using opgs, 1271 * so just initialize it 1272 */ 1273 if (!locked || npages < __arraycount(spgs)) 1274 opgs = spgs; 1275 else { 1276 if ((opgs = kmem_alloc(npages * sizeof(*opgs), KM_NOSLEEP)) == 1277 NULL) 1278 return ENOMEM; 1279 } 1280 1281 /* 1282 * call the genfs code to get the pages. `pgs' may be NULL 1283 * when doing read-ahead. 1284 */ 1285 pgs = ap->a_m; 1286 if (write && locked && v3) { 1287 KASSERT(pgs != NULL); 1288 #ifdef DEBUG 1289 1290 /* 1291 * If PGO_LOCKED is set, real pages shouldn't exists 1292 * in the array. 1293 */ 1294 1295 for (i = 0; i < npages; i++) 1296 KDASSERT(pgs[i] == NULL || pgs[i] == PGO_DONTCARE); 1297 #endif 1298 memcpy(opgs, pgs, npages * sizeof(struct vm_pages *)); 1299 } 1300 error = genfs_getpages(v); 1301 if (error) 1302 goto out; 1303 1304 /* 1305 * for read faults where the nfs node is not yet marked NMODIFIED, 1306 * set PG_RDONLY on the pages so that we come back here if someone 1307 * tries to modify later via the mapping that will be entered for 1308 * this fault. 1309 */ 1310 1311 if (!write && (np->n_flag & NMODIFIED) == 0 && pgs != NULL) { 1312 if (!locked) { 1313 rw_enter(uobj->vmobjlock, RW_WRITER); 1314 } 1315 for (i = 0; i < npages; i++) { 1316 pg = pgs[i]; 1317 if (pg == NULL || pg == PGO_DONTCARE) { 1318 continue; 1319 } 1320 pg->flags |= PG_RDONLY; 1321 } 1322 if (!locked) { 1323 rw_exit(uobj->vmobjlock); 1324 } 1325 } 1326 if (!write) 1327 goto out; 1328 1329 /* 1330 * this is a write fault, update the commit info. 1331 */ 1332 1333 origoffset = ap->a_offset; 1334 len = npages << PAGE_SHIFT; 1335 1336 if (v3) { 1337 if (!locked) { 1338 mutex_enter(&np->n_commitlock); 1339 } else { 1340 if (!mutex_tryenter(&np->n_commitlock)) { 1341 1342 /* 1343 * tell the caller that there are no pages 1344 * available and put back original pgs array. 1345 */ 1346 1347 *ap->a_count = 0; 1348 memcpy(pgs, opgs, 1349 npages * sizeof(struct vm_pages *)); 1350 error = EBUSY; 1351 goto out; 1352 } 1353 } 1354 nfs_del_committed_range(vp, origoffset, len); 1355 nfs_del_tobecommitted_range(vp, origoffset, len); 1356 } 1357 np->n_flag |= NMODIFIED; 1358 if (!locked) { 1359 rw_enter(uobj->vmobjlock, RW_WRITER); 1360 } 1361 for (i = 0; i < npages; i++) { 1362 pg = pgs[i]; 1363 if (pg == NULL || pg == PGO_DONTCARE) { 1364 continue; 1365 } 1366 pg->flags &= ~(PG_NEEDCOMMIT | PG_RDONLY); 1367 } 1368 if (!locked) { 1369 rw_exit(uobj->vmobjlock); 1370 } 1371 if (v3) { 1372 mutex_exit(&np->n_commitlock); 1373 } 1374 out: 1375 if (opgs != spgs) 1376 kmem_free(opgs, sizeof(*opgs) * npages); 1377 return error; 1378 }
Cache object: b3728d49b55b2a818135700333550eb2
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