1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26 
  27 /*
  28  * Copyright (c) 2015, Joyent, Inc. All rights reserved.
  29  * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
  30  * Copyright 2016 RackTop Systems.
  31  */
  32 
  33 #include <sys/types.h>
  34 #include <sys/param.h>
  35 #include <sys/t_lock.h>
  36 #include <sys/systm.h>
  37 #include <sys/sysmacros.h>
  38 #include <sys/user.h>
  39 #include <sys/time.h>
  40 #include <sys/vfs.h>
  41 #include <sys/vfs_opreg.h>
  42 #include <sys/vnode.h>
  43 #include <sys/file.h>
  44 #include <sys/fcntl.h>
  45 #include <sys/flock.h>
  46 #include <sys/kmem.h>
  47 #include <sys/uio.h>
  48 #include <sys/errno.h>
  49 #include <sys/stat.h>
  50 #include <sys/cred.h>
  51 #include <sys/dirent.h>
  52 #include <sys/pathname.h>
  53 #include <sys/vmsystm.h>
  54 #include <sys/fs/tmp.h>
  55 #include <sys/fs/tmpnode.h>
  56 #include <sys/mman.h>
  57 #include <vm/hat.h>
  58 #include <vm/seg_vn.h>
  59 #include <vm/seg_map.h>
  60 #include <vm/seg.h>
  61 #include <vm/anon.h>
  62 #include <vm/as.h>
  63 #include <vm/page.h>
  64 #include <vm/pvn.h>
  65 #include <sys/cmn_err.h>
  66 #include <sys/debug.h>
  67 #include <sys/swap.h>
  68 #include <sys/buf.h>
  69 #include <sys/vm.h>
  70 #include <sys/vtrace.h>
  71 #include <sys/policy.h>
  72 #include <fs/fs_subr.h>
  73 
  74 static int      tmp_getapage(struct vnode *, u_offset_t, size_t, uint_t *,
  75         page_t **, size_t, struct seg *, caddr_t, enum seg_rw, struct cred *);
  76 static int      tmp_putapage(struct vnode *, page_t *, u_offset_t *, size_t *,
  77         int, struct cred *);
  78 
  79 /* ARGSUSED1 */
  80 static int
  81 tmp_open(struct vnode **vpp, int flag, struct cred *cred, caller_context_t *ct)
  82 {
  83         /*
  84          * swapon to a tmpfs file is not supported so access
  85          * is denied on open if VISSWAP is set.
  86          */
  87         if ((*vpp)->v_flag & VISSWAP)
  88                 return (EINVAL);
  89         return (0);
  90 }
  91 
  92 /* ARGSUSED1 */
  93 static int
  94 tmp_close(
  95         struct vnode *vp,
  96         int flag,
  97         int count,
  98         offset_t offset,
  99         struct cred *cred,
 100         caller_context_t *ct)
 101 {
 102         cleanlocks(vp, ttoproc(curthread)->p_pid, 0);
 103         cleanshares(vp, ttoproc(curthread)->p_pid);
 104         return (0);
 105 }
 106 
 107 /*
 108  * wrtmp does the real work of write requests for tmpfs.
 109  */
 110 static int
 111 wrtmp(
 112         struct tmount *tm,
 113         struct tmpnode *tp,
 114         struct uio *uio,
 115         struct cred *cr,
 116         struct caller_context *ct)
 117 {
 118         pgcnt_t pageoffset;     /* offset in pages */
 119         ulong_t segmap_offset;  /* pagesize byte offset into segmap */
 120         caddr_t base;           /* base of segmap */
 121         ssize_t bytes;          /* bytes to uiomove */
 122         pfn_t pagenumber;       /* offset in pages into tmp file */
 123         struct vnode *vp;
 124         int error = 0;
 125         int     pagecreate;     /* == 1 if we allocated a page */
 126         int     newpage;
 127         rlim64_t limit = uio->uio_llimit;
 128         long oresid = uio->uio_resid;
 129         timestruc_t now;
 130 
 131         long tn_size_changed = 0;
 132         long old_tn_size;
 133         long new_tn_size;
 134 
 135         vp = TNTOV(tp);
 136         ASSERT(vp->v_type == VREG);
 137 
 138         TRACE_1(TR_FAC_TMPFS, TR_TMPFS_RWTMP_START,
 139             "tmp_wrtmp_start:vp %p", vp);
 140 
 141         ASSERT(RW_WRITE_HELD(&tp->tn_contents));
 142         ASSERT(RW_WRITE_HELD(&tp->tn_rwlock));
 143 
 144         if (MANDLOCK(vp, tp->tn_mode)) {
 145                 rw_exit(&tp->tn_contents);
 146                 /*
 147                  * tmp_getattr ends up being called by chklock
 148                  */
 149                 error = chklock(vp, FWRITE, uio->uio_loffset, uio->uio_resid,
 150                     uio->uio_fmode, ct);
 151                 rw_enter(&tp->tn_contents, RW_WRITER);
 152                 if (error != 0) {
 153                         TRACE_2(TR_FAC_TMPFS, TR_TMPFS_RWTMP_END,
 154                             "tmp_wrtmp_end:vp %p error %d", vp, error);
 155                         return (error);
 156                 }
 157         }
 158 
 159         if (uio->uio_loffset < 0)
 160                 return (EINVAL);
 161 
 162         if (limit == RLIM64_INFINITY || limit > MAXOFFSET_T)
 163                 limit = MAXOFFSET_T;
 164 
 165         if (uio->uio_loffset >= limit) {
 166                 proc_t *p = ttoproc(curthread);
 167 
 168                 mutex_enter(&p->p_lock);
 169                 (void) rctl_action(rctlproc_legacy[RLIMIT_FSIZE], p->p_rctls,
 170                     p, RCA_UNSAFE_SIGINFO);
 171                 mutex_exit(&p->p_lock);
 172                 return (EFBIG);
 173         }
 174 
 175         if (uio->uio_loffset >= MAXOFF_T) {
 176                 TRACE_2(TR_FAC_TMPFS, TR_TMPFS_RWTMP_END,
 177                     "tmp_wrtmp_end:vp %p error %d", vp, EINVAL);
 178                 return (EFBIG);
 179         }
 180 
 181         if (uio->uio_resid == 0) {
 182                 TRACE_2(TR_FAC_TMPFS, TR_TMPFS_RWTMP_END,
 183                     "tmp_wrtmp_end:vp %p error %d", vp, 0);
 184                 return (0);
 185         }
 186 
 187         if (limit > MAXOFF_T)
 188                 limit = MAXOFF_T;
 189 
 190         do {
 191                 long    offset;
 192                 long    delta;
 193 
 194                 offset = (long)uio->uio_offset;
 195                 pageoffset = offset & PAGEOFFSET;
 196                 /*
 197                  * A maximum of PAGESIZE bytes of data is transferred
 198                  * each pass through this loop
 199                  */
 200                 bytes = MIN(PAGESIZE - pageoffset, uio->uio_resid);
 201 
 202                 if (offset + bytes >= limit) {
 203                         if (offset >= limit) {
 204                                 error = EFBIG;
 205                                 goto out;
 206                         }
 207                         bytes = limit - offset;
 208                 }
 209                 pagenumber = btop(offset);
 210 
 211                 /*
 212                  * delta is the amount of anonymous memory
 213                  * to reserve for the file.
 214                  * We always reserve in pagesize increments so
 215                  * unless we're extending the file into a new page,
 216                  * we don't need to call tmp_resv.
 217                  */
 218                 delta = offset + bytes -
 219                     P2ROUNDUP_TYPED(tp->tn_size, PAGESIZE, u_offset_t);
 220                 if (delta > 0) {
 221                         pagecreate = 1;
 222                         if (tmp_resv(tm, tp, delta, pagecreate)) {
 223                                 /*
 224                                  * Log file system full in the zone that owns
 225                                  * the tmpfs mount, as well as in the global
 226                                  * zone if necessary.
 227                                  */
 228                                 zcmn_err(tm->tm_vfsp->vfs_zone->zone_id,
 229                                     CE_WARN, "%s: File system full, "
 230                                     "swap space limit exceeded",
 231                                     tm->tm_mntpath);
 232 
 233                                 if (tm->tm_vfsp->vfs_zone->zone_id !=
 234                                     GLOBAL_ZONEID) {
 235 
 236                                         vfs_t *vfs = tm->tm_vfsp;
 237 
 238                                         zcmn_err(GLOBAL_ZONEID,
 239                                             CE_WARN, "%s: File system full, "
 240                                             "swap space limit exceeded",
 241                                             vfs->vfs_vnodecovered->v_path);
 242                                 }
 243                                 error = ENOSPC;
 244                                 break;
 245                         }
 246                         tmpnode_growmap(tp, (ulong_t)offset + bytes);
 247                 }
 248                 /* grow the file to the new length */
 249                 if (offset + bytes > tp->tn_size) {
 250                         tn_size_changed = 1;
 251                         old_tn_size = tp->tn_size;
 252                         /*
 253                          * Postpone updating tp->tn_size until uiomove() is
 254                          * done.
 255                          */
 256                         new_tn_size = offset + bytes;
 257                 }
 258                 if (bytes == PAGESIZE) {
 259                         /*
 260                          * Writing whole page so reading from disk
 261                          * is a waste
 262                          */
 263                         pagecreate = 1;
 264                 } else {
 265                         pagecreate = 0;
 266                 }
 267                 /*
 268                  * If writing past EOF or filling in a hole
 269                  * we need to allocate an anon slot.
 270                  */
 271                 if (anon_get_ptr(tp->tn_anon, pagenumber) == NULL) {
 272                         (void) anon_set_ptr(tp->tn_anon, pagenumber,
 273                             anon_alloc(vp, ptob(pagenumber)), ANON_SLEEP);
 274                         pagecreate = 1;
 275                         tp->tn_nblocks++;
 276                 }
 277 
 278                 /*
 279                  * We have to drop the contents lock to allow the VM
 280                  * system to reacquire it in tmp_getpage()
 281                  */
 282                 rw_exit(&tp->tn_contents);
 283 
 284                 /*
 285                  * Touch the page and fault it in if it is not in core
 286                  * before segmap_getmapflt or vpm_data_copy can lock it.
 287                  * This is to avoid the deadlock if the buffer is mapped
 288                  * to the same file through mmap which we want to write.
 289                  */
 290                 uio_prefaultpages((long)bytes, uio);
 291 
 292                 newpage = 0;
 293                 if (vpm_enable) {
 294                         /*
 295                          * Copy data. If new pages are created, part of
 296                          * the page that is not written will be initizliazed
 297                          * with zeros.
 298                          */
 299                         error = vpm_data_copy(vp, offset, bytes, uio,
 300                             !pagecreate, &newpage, 1, S_WRITE);
 301                 } else {
 302                         /* Get offset within the segmap mapping */
 303                         segmap_offset = (offset & PAGEMASK) & MAXBOFFSET;
 304                         base = segmap_getmapflt(segkmap, vp,
 305                             (offset &  MAXBMASK), PAGESIZE, !pagecreate,
 306                             S_WRITE);
 307                 }
 308 
 309 
 310                 if (!vpm_enable && pagecreate) {
 311                         /*
 312                          * segmap_pagecreate() returns 1 if it calls
 313                          * page_create_va() to allocate any pages.
 314                          */
 315                         newpage = segmap_pagecreate(segkmap,
 316                             base + segmap_offset, (size_t)PAGESIZE, 0);
 317                         /*
 318                          * Clear from the beginning of the page to the starting
 319                          * offset of the data.
 320                          */
 321                         if (pageoffset != 0)
 322                                 (void) kzero(base + segmap_offset,
 323                                     (size_t)pageoffset);
 324                 }
 325 
 326                 if (!vpm_enable) {
 327                         error = uiomove(base + segmap_offset + pageoffset,
 328                             (long)bytes, UIO_WRITE, uio);
 329                 }
 330 
 331                 if (!vpm_enable && pagecreate &&
 332                     uio->uio_offset < P2ROUNDUP(offset + bytes, PAGESIZE)) {
 333                         long    zoffset; /* zero from offset into page */
 334                         /*
 335                          * We created pages w/o initializing them completely,
 336                          * thus we need to zero the part that wasn't set up.
 337                          * This happens on most EOF write cases and if
 338                          * we had some sort of error during the uiomove.
 339                          */
 340                         long nmoved;
 341 
 342                         nmoved = uio->uio_offset - offset;
 343                         ASSERT((nmoved + pageoffset) <= PAGESIZE);
 344 
 345                         /*
 346                          * Zero from the end of data in the page to the
 347                          * end of the page.
 348                          */
 349                         if ((zoffset = pageoffset + nmoved) < PAGESIZE)
 350                                 (void) kzero(base + segmap_offset + zoffset,
 351                                     (size_t)PAGESIZE - zoffset);
 352                 }
 353 
 354                 /*
 355                  * Unlock the pages which have been allocated by
 356                  * page_create_va() in segmap_pagecreate()
 357                  */
 358                 if (!vpm_enable && newpage) {
 359                         segmap_pageunlock(segkmap, base + segmap_offset,
 360                             (size_t)PAGESIZE, S_WRITE);
 361                 }
 362 
 363                 if (error) {
 364                         /*
 365                          * If we failed on a write, we must
 366                          * be sure to invalidate any pages that may have
 367                          * been allocated.
 368                          */
 369                         if (vpm_enable) {
 370                                 (void) vpm_sync_pages(vp, offset, PAGESIZE,
 371                                     SM_INVAL);
 372                         } else {
 373                                 (void) segmap_release(segkmap, base, SM_INVAL);
 374                         }
 375                 } else {
 376                         if (vpm_enable) {
 377                                 error = vpm_sync_pages(vp, offset, PAGESIZE,
 378                                     0);
 379                         } else {
 380                                 error = segmap_release(segkmap, base, 0);
 381                         }
 382                 }
 383 
 384                 /*
 385                  * Re-acquire contents lock.
 386                  */
 387                 rw_enter(&tp->tn_contents, RW_WRITER);
 388 
 389                 /*
 390                  * Update tn_size.
 391                  */
 392                 if (tn_size_changed)
 393                         tp->tn_size = new_tn_size;
 394 
 395                 /*
 396                  * If the uiomove failed, fix up tn_size.
 397                  */
 398                 if (error) {
 399                         if (tn_size_changed) {
 400                                 /*
 401                                  * The uiomove failed, and we
 402                                  * allocated blocks,so get rid
 403                                  * of them.
 404                                  */
 405                                 (void) tmpnode_trunc(tm, tp,
 406                                     (ulong_t)old_tn_size);
 407                         }
 408                 } else {
 409                         /*
 410                          * XXX - Can this be out of the loop?
 411                          */
 412                         if ((tp->tn_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) &&
 413                             (tp->tn_mode & (S_ISUID | S_ISGID)) &&
 414                             secpolicy_vnode_setid_retain(cr,
 415                             (tp->tn_mode & S_ISUID) != 0 && tp->tn_uid == 0)) {
 416                                 /*
 417                                  * Clear Set-UID & Set-GID bits on
 418                                  * successful write if not privileged
 419                                  * and at least one of the execute bits
 420                                  * is set.  If we always clear Set-GID,
 421                                  * mandatory file and record locking is
 422                                  * unuseable.
 423                                  */
 424                                 tp->tn_mode &= ~(S_ISUID | S_ISGID);
 425                         }
 426                         gethrestime(&now);
 427                         tp->tn_mtime = now;
 428                         tp->tn_ctime = now;
 429                 }
 430         } while (error == 0 && uio->uio_resid > 0 && bytes != 0);
 431 
 432 out:
 433         /*
 434          * If we've already done a partial-write, terminate
 435          * the write but return no error.
 436          */
 437         if (oresid != uio->uio_resid)
 438                 error = 0;
 439         TRACE_2(TR_FAC_TMPFS, TR_TMPFS_RWTMP_END,
 440             "tmp_wrtmp_end:vp %p error %d", vp, error);
 441         return (error);
 442 }
 443 
 444 /*
 445  * rdtmp does the real work of read requests for tmpfs.
 446  */
 447 static int
 448 rdtmp(
 449         struct tmount *tm,
 450         struct tmpnode *tp,
 451         struct uio *uio,
 452         struct caller_context *ct)
 453 {
 454         ulong_t pageoffset;     /* offset in tmpfs file (uio_offset) */
 455         ulong_t segmap_offset;  /* pagesize byte offset into segmap */
 456         caddr_t base;           /* base of segmap */
 457         ssize_t bytes;          /* bytes to uiomove */
 458         struct vnode *vp;
 459         int error;
 460         long oresid = uio->uio_resid;
 461 
 462 #if defined(lint)
 463         tm = tm;
 464 #endif
 465         vp = TNTOV(tp);
 466 
 467         TRACE_1(TR_FAC_TMPFS, TR_TMPFS_RWTMP_START, "tmp_rdtmp_start:vp %p",
 468             vp);
 469 
 470         ASSERT(RW_LOCK_HELD(&tp->tn_contents));
 471 
 472         if (MANDLOCK(vp, tp->tn_mode)) {
 473                 rw_exit(&tp->tn_contents);
 474                 /*
 475                  * tmp_getattr ends up being called by chklock
 476                  */
 477                 error = chklock(vp, FREAD, uio->uio_loffset, uio->uio_resid,
 478                     uio->uio_fmode, ct);
 479                 rw_enter(&tp->tn_contents, RW_READER);
 480                 if (error != 0) {
 481                         TRACE_2(TR_FAC_TMPFS, TR_TMPFS_RWTMP_END,
 482                             "tmp_rdtmp_end:vp %p error %d", vp, error);
 483                         return (error);
 484                 }
 485         }
 486         ASSERT(tp->tn_type == VREG);
 487 
 488         if (uio->uio_loffset >= MAXOFF_T) {
 489                 TRACE_2(TR_FAC_TMPFS, TR_TMPFS_RWTMP_END,
 490                     "tmp_rdtmp_end:vp %p error %d", vp, EINVAL);
 491                 return (0);
 492         }
 493         if (uio->uio_loffset < 0)
 494                 return (EINVAL);
 495         if (uio->uio_resid == 0) {
 496                 TRACE_2(TR_FAC_TMPFS, TR_TMPFS_RWTMP_END,
 497                     "tmp_rdtmp_end:vp %p error %d", vp, 0);
 498                 return (0);
 499         }
 500 
 501         vp = TNTOV(tp);
 502 
 503         do {
 504                 long diff;
 505                 long offset;
 506 
 507                 offset = uio->uio_offset;
 508                 pageoffset = offset & PAGEOFFSET;
 509                 bytes = MIN(PAGESIZE - pageoffset, uio->uio_resid);
 510 
 511                 diff = tp->tn_size - offset;
 512 
 513                 if (diff <= 0) {
 514                         error = 0;
 515                         goto out;
 516                 }
 517                 if (diff < bytes)
 518                         bytes = diff;
 519 
 520                 /*
 521                  * We have to drop the contents lock to allow the VM system
 522                  * to reacquire it in tmp_getpage() should the uiomove cause a
 523                  * pagefault.
 524                  */
 525                 rw_exit(&tp->tn_contents);
 526 
 527                 if (vpm_enable) {
 528                         /*
 529                          * Copy data.
 530                          */
 531                         error = vpm_data_copy(vp, offset, bytes, uio, 1, NULL,
 532                             0, S_READ);
 533                 } else {
 534                         segmap_offset = (offset & PAGEMASK) & MAXBOFFSET;
 535                         base = segmap_getmapflt(segkmap, vp, offset & MAXBMASK,
 536                             bytes, 1, S_READ);
 537 
 538                         error = uiomove(base + segmap_offset + pageoffset,
 539                             (long)bytes, UIO_READ, uio);
 540                 }
 541 
 542                 if (error) {
 543                         if (vpm_enable) {
 544                                 (void) vpm_sync_pages(vp, offset, PAGESIZE, 0);
 545                         } else {
 546                                 (void) segmap_release(segkmap, base, 0);
 547                         }
 548                 } else {
 549                         if (vpm_enable) {
 550                                 error = vpm_sync_pages(vp, offset, PAGESIZE,
 551                                     0);
 552                         } else {
 553                                 error = segmap_release(segkmap, base, 0);
 554                         }
 555                 }
 556 
 557                 /*
 558                  * Re-acquire contents lock.
 559                  */
 560                 rw_enter(&tp->tn_contents, RW_READER);
 561 
 562         } while (error == 0 && uio->uio_resid > 0);
 563 
 564 out:
 565         gethrestime(&tp->tn_atime);
 566 
 567         /*
 568          * If we've already done a partial read, terminate
 569          * the read but return no error.
 570          */
 571         if (oresid != uio->uio_resid)
 572                 error = 0;
 573 
 574         TRACE_2(TR_FAC_TMPFS, TR_TMPFS_RWTMP_END,
 575             "tmp_rdtmp_end:vp %x error %d", vp, error);
 576         return (error);
 577 }
 578 
 579 /* ARGSUSED2 */
 580 static int
 581 tmp_read(struct vnode *vp, struct uio *uiop, int ioflag, cred_t *cred,
 582     struct caller_context *ct)
 583 {
 584         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
 585         struct tmount *tm = (struct tmount *)VTOTM(vp);
 586         int error;
 587 
 588         /*
 589          * We don't currently support reading non-regular files
 590          */
 591         if (vp->v_type == VDIR)
 592                 return (EISDIR);
 593         if (vp->v_type != VREG)
 594                 return (EINVAL);
 595         /*
 596          * tmp_rwlock should have already been called from layers above
 597          */
 598         ASSERT(RW_READ_HELD(&tp->tn_rwlock));
 599 
 600         rw_enter(&tp->tn_contents, RW_READER);
 601 
 602         error = rdtmp(tm, tp, uiop, ct);
 603 
 604         rw_exit(&tp->tn_contents);
 605 
 606         return (error);
 607 }
 608 
 609 static int
 610 tmp_write(struct vnode *vp, struct uio *uiop, int ioflag, struct cred *cred,
 611     struct caller_context *ct)
 612 {
 613         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
 614         struct tmount *tm = (struct tmount *)VTOTM(vp);
 615         int error;
 616 
 617         /*
 618          * We don't currently support writing to non-regular files
 619          */
 620         if (vp->v_type != VREG)
 621                 return (EINVAL);        /* XXX EISDIR? */
 622 
 623         /*
 624          * tmp_rwlock should have already been called from layers above
 625          */
 626         ASSERT(RW_WRITE_HELD(&tp->tn_rwlock));
 627 
 628         rw_enter(&tp->tn_contents, RW_WRITER);
 629 
 630         if (ioflag & FAPPEND) {
 631                 /*
 632                  * In append mode start at end of file.
 633                  */
 634                 uiop->uio_loffset = tp->tn_size;
 635         }
 636 
 637         error = wrtmp(tm, tp, uiop, cred, ct);
 638 
 639         rw_exit(&tp->tn_contents);
 640 
 641         return (error);
 642 }
 643 
 644 /* ARGSUSED */
 645 static int
 646 tmp_ioctl(
 647         struct vnode *vp,
 648         int com,
 649         intptr_t data,
 650         int flag,
 651         struct cred *cred,
 652         int *rvalp,
 653         caller_context_t *ct)
 654 {
 655         return (ENOTTY);
 656 }
 657 
 658 /* ARGSUSED2 */
 659 static int
 660 tmp_getattr(
 661         struct vnode *vp,
 662         struct vattr *vap,
 663         int flags,
 664         struct cred *cred,
 665         caller_context_t *ct)
 666 {
 667         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
 668         struct vnode *mvp;
 669         struct vattr va;
 670         int attrs = 1;
 671 
 672         /*
 673          * A special case to handle the root tnode on a diskless nfs
 674          * client who may have had its uid and gid inherited
 675          * from an nfs vnode with nobody ownership.  Likely the
 676          * root filesystem. After nfs is fully functional the uid/gid
 677          * may be mapable so ask again.
 678          * vfsp can't get unmounted because we hold vp.
 679          */
 680         if (vp->v_flag & VROOT &&
 681             (mvp = vp->v_vfsp->vfs_vnodecovered) != NULL) {
 682                 mutex_enter(&tp->tn_tlock);
 683                 if (tp->tn_uid == UID_NOBODY || tp->tn_gid == GID_NOBODY) {
 684                         mutex_exit(&tp->tn_tlock);
 685                         bzero(&va, sizeof (struct vattr));
 686                         va.va_mask = AT_UID|AT_GID;
 687                         attrs = VOP_GETATTR(mvp, &va, 0, cred, ct);
 688                 } else {
 689                         mutex_exit(&tp->tn_tlock);
 690                 }
 691         }
 692         mutex_enter(&tp->tn_tlock);
 693         if (attrs == 0) {
 694                 tp->tn_uid = va.va_uid;
 695                 tp->tn_gid = va.va_gid;
 696         }
 697         vap->va_type = vp->v_type;
 698         vap->va_mode = tp->tn_mode & MODEMASK;
 699         vap->va_uid = tp->tn_uid;
 700         vap->va_gid = tp->tn_gid;
 701         vap->va_fsid = tp->tn_fsid;
 702         vap->va_nodeid = (ino64_t)tp->tn_nodeid;
 703         vap->va_nlink = tp->tn_nlink;
 704         vap->va_size = (u_offset_t)tp->tn_size;
 705         vap->va_atime = tp->tn_atime;
 706         vap->va_mtime = tp->tn_mtime;
 707         vap->va_ctime = tp->tn_ctime;
 708         vap->va_blksize = PAGESIZE;
 709         vap->va_rdev = tp->tn_rdev;
 710         vap->va_seq = tp->tn_seq;
 711 
 712         /*
 713          * XXX Holes are not taken into account.  We could take the time to
 714          * run through the anon array looking for allocated slots...
 715          */
 716         vap->va_nblocks = (fsblkcnt64_t)btodb(ptob(btopr(vap->va_size)));
 717         mutex_exit(&tp->tn_tlock);
 718         return (0);
 719 }
 720 
 721 /*ARGSUSED4*/
 722 static int
 723 tmp_setattr(
 724         struct vnode *vp,
 725         struct vattr *vap,
 726         int flags,
 727         struct cred *cred,
 728         caller_context_t *ct)
 729 {
 730         struct tmount *tm = (struct tmount *)VTOTM(vp);
 731         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
 732         int error = 0;
 733         struct vattr *get;
 734         long mask;
 735 
 736         /*
 737          * Cannot set these attributes
 738          */
 739         if ((vap->va_mask & AT_NOSET) || (vap->va_mask & AT_XVATTR))
 740                 return (EINVAL);
 741 
 742         mutex_enter(&tp->tn_tlock);
 743 
 744         get = &tp->tn_attr;
 745         /*
 746          * Change file access modes. Must be owner or have sufficient
 747          * privileges.
 748          */
 749         error = secpolicy_vnode_setattr(cred, vp, vap, get, flags, tmp_taccess,
 750             tp);
 751 
 752         if (error)
 753                 goto out;
 754 
 755         mask = vap->va_mask;
 756 
 757         if (mask & AT_MODE) {
 758                 get->va_mode &= S_IFMT;
 759                 get->va_mode |= vap->va_mode & ~S_IFMT;
 760         }
 761 
 762         if (mask & AT_UID)
 763                 get->va_uid = vap->va_uid;
 764         if (mask & AT_GID)
 765                 get->va_gid = vap->va_gid;
 766         if (mask & AT_ATIME)
 767                 get->va_atime = vap->va_atime;
 768         if (mask & AT_MTIME)
 769                 get->va_mtime = vap->va_mtime;
 770 
 771         if (mask & (AT_UID | AT_GID | AT_MODE | AT_MTIME))
 772                 gethrestime(&tp->tn_ctime);
 773 
 774         if (mask & AT_SIZE) {
 775                 ASSERT(vp->v_type != VDIR);
 776 
 777                 /* Don't support large files. */
 778                 if (vap->va_size > MAXOFF_T) {
 779                         error = EFBIG;
 780                         goto out;
 781                 }
 782                 mutex_exit(&tp->tn_tlock);
 783 
 784                 rw_enter(&tp->tn_rwlock, RW_WRITER);
 785                 rw_enter(&tp->tn_contents, RW_WRITER);
 786                 error = tmpnode_trunc(tm, tp, (ulong_t)vap->va_size);
 787                 rw_exit(&tp->tn_contents);
 788                 rw_exit(&tp->tn_rwlock);
 789 
 790                 if (error == 0 && vap->va_size == 0)
 791                         vnevent_truncate(vp, ct);
 792 
 793                 goto out1;
 794         }
 795 out:
 796         mutex_exit(&tp->tn_tlock);
 797 out1:
 798         return (error);
 799 }
 800 
 801 /* ARGSUSED2 */
 802 static int
 803 tmp_access(
 804         struct vnode *vp,
 805         int mode,
 806         int flags,
 807         struct cred *cred,
 808         caller_context_t *ct)
 809 {
 810         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
 811         int error;
 812 
 813         mutex_enter(&tp->tn_tlock);
 814         error = tmp_taccess(tp, mode, cred);
 815         mutex_exit(&tp->tn_tlock);
 816         return (error);
 817 }
 818 
 819 /* ARGSUSED3 */
 820 static int
 821 tmp_lookup(
 822         struct vnode *dvp,
 823         char *nm,
 824         struct vnode **vpp,
 825         struct pathname *pnp,
 826         int flags,
 827         struct vnode *rdir,
 828         struct cred *cred,
 829         caller_context_t *ct,
 830         int *direntflags,
 831         pathname_t *realpnp)
 832 {
 833         struct tmpnode *tp = (struct tmpnode *)VTOTN(dvp);
 834         struct tmpnode *ntp = NULL;
 835         int error;
 836 
 837 
 838         /* allow cd into @ dir */
 839         if (flags & LOOKUP_XATTR) {
 840                 struct tmpnode *xdp;
 841                 struct tmount *tm;
 842 
 843                 /*
 844                  * don't allow attributes if not mounted XATTR support
 845                  */
 846                 if (!(dvp->v_vfsp->vfs_flag & VFS_XATTR))
 847                         return (EINVAL);
 848 
 849                 if (tp->tn_flags & ISXATTR)
 850                         /* No attributes on attributes */
 851                         return (EINVAL);
 852 
 853                 rw_enter(&tp->tn_rwlock, RW_WRITER);
 854                 if (tp->tn_xattrdp == NULL) {
 855                         if (!(flags & CREATE_XATTR_DIR)) {
 856                                 rw_exit(&tp->tn_rwlock);
 857                                 return (ENOENT);
 858                         }
 859 
 860                         /*
 861                          * No attribute directory exists for this
 862                          * node - create the attr dir as a side effect
 863                          * of this lookup.
 864                          */
 865 
 866                         /*
 867                          * Make sure we have adequate permission...
 868                          */
 869 
 870                         if ((error = tmp_taccess(tp, VWRITE, cred)) != 0) {
 871                                 rw_exit(&tp->tn_rwlock);
 872                                 return (error);
 873                         }
 874 
 875                         xdp = tmp_memalloc(sizeof (struct tmpnode),
 876                             TMP_MUSTHAVE);
 877                         tm = VTOTM(dvp);
 878                         tmpnode_init(tm, xdp, &tp->tn_attr, NULL);
 879                         /*
 880                          * Fix-up fields unique to attribute directories.
 881                          */
 882                         xdp->tn_flags = ISXATTR;
 883                         xdp->tn_type = VDIR;
 884                         if (tp->tn_type == VDIR) {
 885                                 xdp->tn_mode = tp->tn_attr.va_mode;
 886                         } else {
 887                                 xdp->tn_mode = 0700;
 888                                 if (tp->tn_attr.va_mode & 0040)
 889                                         xdp->tn_mode |= 0750;
 890                                 if (tp->tn_attr.va_mode & 0004)
 891                                         xdp->tn_mode |= 0705;
 892                         }
 893                         xdp->tn_vnode->v_type = VDIR;
 894                         xdp->tn_vnode->v_flag |= V_XATTRDIR;
 895                         tdirinit(tp, xdp);
 896                         tp->tn_xattrdp = xdp;
 897                 } else {
 898                         VN_HOLD(tp->tn_xattrdp->tn_vnode);
 899                 }
 900                 *vpp = TNTOV(tp->tn_xattrdp);
 901                 rw_exit(&tp->tn_rwlock);
 902                 return (0);
 903         }
 904 
 905         /*
 906          * Null component name is a synonym for directory being searched.
 907          */
 908         if (*nm == '\0') {
 909                 VN_HOLD(dvp);
 910                 *vpp = dvp;
 911                 return (0);
 912         }
 913         ASSERT(tp);
 914 
 915         error = tdirlookup(tp, nm, &ntp, cred);
 916 
 917         if (error == 0) {
 918                 ASSERT(ntp);
 919                 *vpp = TNTOV(ntp);
 920                 /*
 921                  * If vnode is a device return special vnode instead
 922                  */
 923                 if (IS_DEVVP(*vpp)) {
 924                         struct vnode *newvp;
 925 
 926                         newvp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type,
 927                             cred);
 928                         VN_RELE(*vpp);
 929                         *vpp = newvp;
 930                 }
 931         }
 932         TRACE_4(TR_FAC_TMPFS, TR_TMPFS_LOOKUP,
 933             "tmpfs lookup:vp %p name %s vpp %p error %d",
 934             dvp, nm, vpp, error);
 935         return (error);
 936 }
 937 
 938 /*ARGSUSED7*/
 939 static int
 940 tmp_create(
 941         struct vnode *dvp,
 942         char *nm,
 943         struct vattr *vap,
 944         enum vcexcl exclusive,
 945         int mode,
 946         struct vnode **vpp,
 947         struct cred *cred,
 948         int flag,
 949         caller_context_t *ct,
 950         vsecattr_t *vsecp)
 951 {
 952         struct tmpnode *parent;
 953         struct tmount *tm;
 954         struct tmpnode *self;
 955         int error;
 956         struct tmpnode *oldtp;
 957 
 958 again:
 959         parent = (struct tmpnode *)VTOTN(dvp);
 960         tm = (struct tmount *)VTOTM(dvp);
 961         self = NULL;
 962         error = 0;
 963         oldtp = NULL;
 964 
 965         /* device files not allowed in ext. attr dirs */
 966         if ((parent->tn_flags & ISXATTR) &&
 967             (vap->va_type == VBLK || vap->va_type == VCHR ||
 968             vap->va_type == VFIFO || vap->va_type == VDOOR ||
 969             vap->va_type == VSOCK || vap->va_type == VPORT))
 970                         return (EINVAL);
 971 
 972         if (vap->va_type == VREG && (vap->va_mode & VSVTX)) {
 973                 /* Must be privileged to set sticky bit */
 974                 if (secpolicy_vnode_stky_modify(cred))
 975                         vap->va_mode &= ~VSVTX;
 976         } else if (vap->va_type == VNON) {
 977                 return (EINVAL);
 978         }
 979 
 980         /*
 981          * Null component name is a synonym for directory being searched.
 982          */
 983         if (*nm == '\0') {
 984                 VN_HOLD(dvp);
 985                 oldtp = parent;
 986         } else {
 987                 error = tdirlookup(parent, nm, &oldtp, cred);
 988         }
 989 
 990         if (error == 0) {       /* name found */
 991                 boolean_t trunc = B_FALSE;
 992 
 993                 ASSERT(oldtp);
 994 
 995                 rw_enter(&oldtp->tn_rwlock, RW_WRITER);
 996 
 997                 /*
 998                  * if create/read-only an existing
 999                  * directory, allow it
1000                  */
1001                 if (exclusive == EXCL)
1002                         error = EEXIST;
1003                 else if ((oldtp->tn_type == VDIR) && (mode & VWRITE))
1004                         error = EISDIR;
1005                 else {
1006                         error = tmp_taccess(oldtp, mode, cred);
1007                 }
1008 
1009                 if (error) {
1010                         rw_exit(&oldtp->tn_rwlock);
1011                         tmpnode_rele(oldtp);
1012                         return (error);
1013                 }
1014                 *vpp = TNTOV(oldtp);
1015                 if ((*vpp)->v_type == VREG && (vap->va_mask & AT_SIZE) &&
1016                     vap->va_size == 0) {
1017                         rw_enter(&oldtp->tn_contents, RW_WRITER);
1018                         (void) tmpnode_trunc(tm, oldtp, 0);
1019                         rw_exit(&oldtp->tn_contents);
1020                         trunc = B_TRUE;
1021                 }
1022                 rw_exit(&oldtp->tn_rwlock);
1023                 if (IS_DEVVP(*vpp)) {
1024                         struct vnode *newvp;
1025 
1026                         newvp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type,
1027                             cred);
1028                         VN_RELE(*vpp);
1029                         if (newvp == NULL) {
1030                                 return (ENOSYS);
1031                         }
1032                         *vpp = newvp;
1033                 }
1034 
1035                 if (trunc)
1036                         vnevent_create(*vpp, ct);
1037 
1038                 return (0);
1039         }
1040 
1041         if (error != ENOENT)
1042                 return (error);
1043 
1044         rw_enter(&parent->tn_rwlock, RW_WRITER);
1045         error = tdirenter(tm, parent, nm, DE_CREATE,
1046             (struct tmpnode *)NULL, (struct tmpnode *)NULL,
1047             vap, &self, cred, ct);
1048         rw_exit(&parent->tn_rwlock);
1049 
1050         if (error) {
1051                 if (self)
1052                         tmpnode_rele(self);
1053 
1054                 if (error == EEXIST) {
1055                         /*
1056                          * This means that the file was created sometime
1057                          * after we checked and did not find it and when
1058                          * we went to create it.
1059                          * Since creat() is supposed to truncate a file
1060                          * that already exits go back to the begining
1061                          * of the function. This time we will find it
1062                          * and go down the tmp_trunc() path
1063                          */
1064                         goto again;
1065                 }
1066                 return (error);
1067         }
1068 
1069         *vpp = TNTOV(self);
1070 
1071         if (!error && IS_DEVVP(*vpp)) {
1072                 struct vnode *newvp;
1073 
1074                 newvp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cred);
1075                 VN_RELE(*vpp);
1076                 if (newvp == NULL)
1077                         return (ENOSYS);
1078                 *vpp = newvp;
1079         }
1080         TRACE_3(TR_FAC_TMPFS, TR_TMPFS_CREATE,
1081             "tmpfs create:dvp %p nm %s vpp %p", dvp, nm, vpp);
1082         return (0);
1083 }
1084 
1085 /* ARGSUSED3 */
1086 static int
1087 tmp_remove(
1088         struct vnode *dvp,
1089         char *nm,
1090         struct cred *cred,
1091         caller_context_t *ct,
1092         int flags)
1093 {
1094         struct tmpnode *parent = (struct tmpnode *)VTOTN(dvp);
1095         int error;
1096         struct tmpnode *tp = NULL;
1097 
1098         error = tdirlookup(parent, nm, &tp, cred);
1099         if (error)
1100                 return (error);
1101 
1102         ASSERT(tp);
1103         rw_enter(&parent->tn_rwlock, RW_WRITER);
1104         rw_enter(&tp->tn_rwlock, RW_WRITER);
1105 
1106         error = tp->tn_type == VDIR ? EPERM :
1107             tdirdelete(parent, tp, nm, DR_REMOVE, cred);
1108 
1109         rw_exit(&tp->tn_rwlock);
1110         rw_exit(&parent->tn_rwlock);
1111         vnevent_remove(TNTOV(tp), dvp, nm, ct);
1112         tmpnode_rele(tp);
1113 
1114         TRACE_3(TR_FAC_TMPFS, TR_TMPFS_REMOVE,
1115             "tmpfs remove:dvp %p nm %s error %d", dvp, nm, error);
1116         return (error);
1117 }
1118 
1119 /* ARGSUSED4 */
1120 static int
1121 tmp_link(
1122         struct vnode *dvp,
1123         struct vnode *srcvp,
1124         char *tnm,
1125         struct cred *cred,
1126         caller_context_t *ct,
1127         int flags)
1128 {
1129         struct tmpnode *parent;
1130         struct tmpnode *from;
1131         struct tmount *tm = (struct tmount *)VTOTM(dvp);
1132         int error;
1133         struct tmpnode *found = NULL;
1134         struct vnode *realvp;
1135 
1136         if (VOP_REALVP(srcvp, &realvp, ct) == 0)
1137                 srcvp = realvp;
1138 
1139         parent = (struct tmpnode *)VTOTN(dvp);
1140         from = (struct tmpnode *)VTOTN(srcvp);
1141 
1142         if (srcvp->v_type == VDIR ||
1143             (from->tn_uid != crgetuid(cred) && secpolicy_basic_link(cred)))
1144                 return (EPERM);
1145 
1146         /*
1147          * Make sure link for extended attributes is valid
1148          * We only support hard linking of xattr's in xattrdir to an xattrdir
1149          */
1150         if ((from->tn_flags & ISXATTR) != (parent->tn_flags & ISXATTR))
1151                 return (EINVAL);
1152 
1153         error = tdirlookup(parent, tnm, &found, cred);
1154         if (error == 0) {
1155                 ASSERT(found);
1156                 tmpnode_rele(found);
1157                 return (EEXIST);
1158         }
1159 
1160         if (error != ENOENT)
1161                 return (error);
1162 
1163         rw_enter(&parent->tn_rwlock, RW_WRITER);
1164         error = tdirenter(tm, parent, tnm, DE_LINK, (struct tmpnode *)NULL,
1165             from, NULL, (struct tmpnode **)NULL, cred, ct);
1166         rw_exit(&parent->tn_rwlock);
1167         if (error == 0) {
1168                 vnevent_link(srcvp, ct);
1169         }
1170         return (error);
1171 }
1172 
1173 /* ARGSUSED5 */
1174 static int
1175 tmp_rename(
1176         struct vnode *odvp,     /* source parent vnode */
1177         char *onm,              /* source name */
1178         struct vnode *ndvp,     /* destination parent vnode */
1179         char *nnm,              /* destination name */
1180         struct cred *cred,
1181         caller_context_t *ct,
1182         int flags)
1183 {
1184         struct tmpnode *fromparent;
1185         struct tmpnode *toparent;
1186         struct tmpnode *fromtp = NULL;  /* source tmpnode */
1187         struct tmpnode *totp;           /* target tmpnode */
1188         struct tmount *tm = (struct tmount *)VTOTM(odvp);
1189         int error;
1190         int samedir = 0;        /* set if odvp == ndvp */
1191         struct vnode *realvp;
1192 
1193         if (VOP_REALVP(ndvp, &realvp, ct) == 0)
1194                 ndvp = realvp;
1195 
1196         fromparent = (struct tmpnode *)VTOTN(odvp);
1197         toparent = (struct tmpnode *)VTOTN(ndvp);
1198 
1199         if ((fromparent->tn_flags & ISXATTR) != (toparent->tn_flags & ISXATTR))
1200                 return (EINVAL);
1201 
1202         mutex_enter(&tm->tm_renamelck);
1203 
1204         /*
1205          * Look up tmpnode of file we're supposed to rename.
1206          */
1207         error = tdirlookup(fromparent, onm, &fromtp, cred);
1208         if (error) {
1209                 mutex_exit(&tm->tm_renamelck);
1210                 return (error);
1211         }
1212 
1213         /*
1214          * Make sure we can delete the old (source) entry.  This
1215          * requires write permission on the containing directory.  If
1216          * that directory is "sticky" it requires further checks.
1217          */
1218         if (((error = tmp_taccess(fromparent, VWRITE, cred)) != 0) ||
1219             (error = tmp_sticky_remove_access(fromparent, fromtp, cred)) != 0)
1220                 goto done;
1221 
1222         /*
1223          * Check for renaming to or from '.' or '..' or that
1224          * fromtp == fromparent
1225          */
1226         if ((onm[0] == '.' &&
1227             (onm[1] == '\0' || (onm[1] == '.' && onm[2] == '\0'))) ||
1228             (nnm[0] == '.' &&
1229             (nnm[1] == '\0' || (nnm[1] == '.' && nnm[2] == '\0'))) ||
1230             (fromparent == fromtp)) {
1231                 error = EINVAL;
1232                 goto done;
1233         }
1234 
1235         samedir = (fromparent == toparent);
1236         /*
1237          * Make sure we can search and rename into the new
1238          * (destination) directory.
1239          */
1240         if (!samedir) {
1241                 error = tmp_taccess(toparent, VEXEC|VWRITE, cred);
1242                 if (error)
1243                         goto done;
1244         }
1245 
1246         if (tdirlookup(toparent, nnm, &totp, cred) == 0) {
1247                 vnevent_pre_rename_dest(TNTOV(totp), ndvp, nnm, ct);
1248                 tmpnode_rele(totp);
1249         }
1250 
1251         /* Notify the target dir. if not the same as the source dir. */
1252         if (ndvp != odvp) {
1253                 vnevent_pre_rename_dest_dir(ndvp, TNTOV(fromtp), nnm, ct);
1254         }
1255 
1256         vnevent_pre_rename_src(TNTOV(fromtp), odvp, onm, ct);
1257 
1258         /*
1259          * Link source to new target
1260          */
1261         rw_enter(&toparent->tn_rwlock, RW_WRITER);
1262         error = tdirenter(tm, toparent, nnm, DE_RENAME,
1263             fromparent, fromtp, (struct vattr *)NULL,
1264             (struct tmpnode **)NULL, cred, ct);
1265         rw_exit(&toparent->tn_rwlock);
1266 
1267         if (error) {
1268                 /*
1269                  * ESAME isn't really an error; it indicates that the
1270                  * operation should not be done because the source and target
1271                  * are the same file, but that no error should be reported.
1272                  */
1273                 if (error == ESAME)
1274                         error = 0;
1275                 goto done;
1276         }
1277 
1278         /*
1279          * Unlink from source.
1280          */
1281         rw_enter(&fromparent->tn_rwlock, RW_WRITER);
1282         rw_enter(&fromtp->tn_rwlock, RW_WRITER);
1283 
1284         error = tdirdelete(fromparent, fromtp, onm, DR_RENAME, cred);
1285 
1286         /*
1287          * The following handles the case where our source tmpnode was
1288          * removed before we got to it.
1289          *
1290          * XXX We should also cleanup properly in the case where tdirdelete
1291          * fails for some other reason.  Currently this case shouldn't happen.
1292          * (see 1184991).
1293          */
1294         if (error == ENOENT)
1295                 error = 0;
1296 
1297         rw_exit(&fromtp->tn_rwlock);
1298         rw_exit(&fromparent->tn_rwlock);
1299 
1300         if (error == 0) {
1301                 vnevent_rename_src(TNTOV(fromtp), odvp, onm, ct);
1302                 /*
1303                  * vnevent_rename_dest is called in tdirenter().
1304                  * Notify the target dir if not same as source dir.
1305                  */
1306                 if (ndvp != odvp)
1307                         vnevent_rename_dest_dir(ndvp, ct);
1308         }
1309 
1310 done:
1311         tmpnode_rele(fromtp);
1312         mutex_exit(&tm->tm_renamelck);
1313 
1314         TRACE_5(TR_FAC_TMPFS, TR_TMPFS_RENAME,
1315             "tmpfs rename:ovp %p onm %s nvp %p nnm %s error %d", odvp, onm,
1316             ndvp, nnm, error);
1317         return (error);
1318 }
1319 
1320 /* ARGSUSED5 */
1321 static int
1322 tmp_mkdir(
1323         struct vnode *dvp,
1324         char *nm,
1325         struct vattr *va,
1326         struct vnode **vpp,
1327         struct cred *cred,
1328         caller_context_t *ct,
1329         int flags,
1330         vsecattr_t *vsecp)
1331 {
1332         struct tmpnode *parent = (struct tmpnode *)VTOTN(dvp);
1333         struct tmpnode *self = NULL;
1334         struct tmount *tm = (struct tmount *)VTOTM(dvp);
1335         int error;
1336 
1337         /* no new dirs allowed in xattr dirs */
1338         if (parent->tn_flags & ISXATTR)
1339                 return (EINVAL);
1340 
1341         /*
1342          * Might be dangling directory.  Catch it here,
1343          * because a ENOENT return from tdirlookup() is
1344          * an "o.k. return".
1345          */
1346         if (parent->tn_nlink == 0)
1347                 return (ENOENT);
1348 
1349         error = tdirlookup(parent, nm, &self, cred);
1350         if (error == 0) {
1351                 ASSERT(self);
1352                 tmpnode_rele(self);
1353                 return (EEXIST);
1354         }
1355         if (error != ENOENT)
1356                 return (error);
1357 
1358         rw_enter(&parent->tn_rwlock, RW_WRITER);
1359         error = tdirenter(tm, parent, nm, DE_MKDIR, (struct tmpnode *)NULL,
1360             (struct tmpnode *)NULL, va, &self, cred, ct);
1361         if (error) {
1362                 rw_exit(&parent->tn_rwlock);
1363                 if (self)
1364                         tmpnode_rele(self);
1365                 return (error);
1366         }
1367         rw_exit(&parent->tn_rwlock);
1368         *vpp = TNTOV(self);
1369         return (0);
1370 }
1371 
1372 /* ARGSUSED4 */
1373 static int
1374 tmp_rmdir(
1375         struct vnode *dvp,
1376         char *nm,
1377         struct vnode *cdir,
1378         struct cred *cred,
1379         caller_context_t *ct,
1380         int flags)
1381 {
1382         struct tmpnode *parent = (struct tmpnode *)VTOTN(dvp);
1383         struct tmpnode *self = NULL;
1384         struct vnode *vp;
1385         int error = 0;
1386 
1387         /*
1388          * Return error when removing . and ..
1389          */
1390         if (strcmp(nm, ".") == 0)
1391                 return (EINVAL);
1392         if (strcmp(nm, "..") == 0)
1393                 return (EEXIST); /* Should be ENOTEMPTY */
1394         error = tdirlookup(parent, nm, &self, cred);
1395         if (error)
1396                 return (error);
1397 
1398         rw_enter(&parent->tn_rwlock, RW_WRITER);
1399         rw_enter(&self->tn_rwlock, RW_WRITER);
1400 
1401         vp = TNTOV(self);
1402         if (vp == dvp || vp == cdir) {
1403                 error = EINVAL;
1404                 goto done1;
1405         }
1406         if (self->tn_type != VDIR) {
1407                 error = ENOTDIR;
1408                 goto done1;
1409         }
1410 
1411         mutex_enter(&self->tn_tlock);
1412         if (self->tn_nlink > 2) {
1413                 mutex_exit(&self->tn_tlock);
1414                 error = EEXIST;
1415                 goto done1;
1416         }
1417         mutex_exit(&self->tn_tlock);
1418 
1419         if (vn_vfswlock(vp)) {
1420                 error = EBUSY;
1421                 goto done1;
1422         }
1423         if (vn_mountedvfs(vp) != NULL) {
1424                 error = EBUSY;
1425                 goto done;
1426         }
1427 
1428         /*
1429          * Check for an empty directory
1430          * i.e. only includes entries for "." and ".."
1431          */
1432         if (self->tn_dirents > 2) {
1433                 error = EEXIST;         /* SIGH should be ENOTEMPTY */
1434                 /*
1435                  * Update atime because checking tn_dirents is logically
1436                  * equivalent to reading the directory
1437                  */
1438                 gethrestime(&self->tn_atime);
1439                 goto done;
1440         }
1441 
1442         error = tdirdelete(parent, self, nm, DR_RMDIR, cred);
1443 done:
1444         vn_vfsunlock(vp);
1445 done1:
1446         rw_exit(&self->tn_rwlock);
1447         rw_exit(&parent->tn_rwlock);
1448         vnevent_rmdir(TNTOV(self), dvp, nm, ct);
1449         tmpnode_rele(self);
1450 
1451         return (error);
1452 }
1453 
1454 /* ARGSUSED2 */
1455 static int
1456 tmp_readdir(
1457         struct vnode *vp,
1458         struct uio *uiop,
1459         struct cred *cred,
1460         int *eofp,
1461         caller_context_t *ct,
1462         int flags)
1463 {
1464         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
1465         struct tdirent *tdp;
1466         int error = 0;
1467         size_t namelen;
1468         struct dirent64 *dp;
1469         ulong_t offset;
1470         ulong_t total_bytes_wanted;
1471         long outcount = 0;
1472         long bufsize;
1473         int reclen;
1474         caddr_t outbuf;
1475 
1476         if (uiop->uio_loffset >= MAXOFF_T) {
1477                 if (eofp)
1478                         *eofp = 1;
1479                 return (0);
1480         }
1481         /*
1482          * assuming system call has already called tmp_rwlock
1483          */
1484         ASSERT(RW_READ_HELD(&tp->tn_rwlock));
1485 
1486         if (uiop->uio_iovcnt != 1)
1487                 return (EINVAL);
1488 
1489         if (vp->v_type != VDIR)
1490                 return (ENOTDIR);
1491 
1492         /*
1493          * There's a window here where someone could have removed
1494          * all the entries in the directory after we put a hold on the
1495          * vnode but before we grabbed the rwlock.  Just return.
1496          */
1497         if (tp->tn_dir == NULL) {
1498                 if (tp->tn_nlink) {
1499                         panic("empty directory 0x%p", (void *)tp);
1500                         /*NOTREACHED*/
1501                 }
1502                 return (0);
1503         }
1504 
1505         /*
1506          * Get space for multiple directory entries
1507          */
1508         total_bytes_wanted = uiop->uio_iov->iov_len;
1509         bufsize = total_bytes_wanted + sizeof (struct dirent64);
1510         outbuf = kmem_alloc(bufsize, KM_SLEEP);
1511 
1512         dp = (struct dirent64 *)outbuf;
1513 
1514 
1515         offset = 0;
1516         tdp = tp->tn_dir;
1517         while (tdp) {
1518                 namelen = strlen(tdp->td_name);      /* no +1 needed */
1519                 offset = tdp->td_offset;
1520                 if (offset >= uiop->uio_offset) {
1521                         reclen = (int)DIRENT64_RECLEN(namelen);
1522                         if (outcount + reclen > total_bytes_wanted) {
1523                                 if (!outcount)
1524                                         /*
1525                                          * Buffer too small for any entries.
1526                                          */
1527                                         error = EINVAL;
1528                                 break;
1529                         }
1530                         ASSERT(tdp->td_tmpnode != NULL);
1531 
1532                         /* use strncpy(9f) to zero out uninitialized bytes */
1533 
1534                         (void) strncpy(dp->d_name, tdp->td_name,
1535                             DIRENT64_NAMELEN(reclen));
1536                         dp->d_reclen = (ushort_t)reclen;
1537                         dp->d_ino = (ino64_t)tdp->td_tmpnode->tn_nodeid;
1538                         dp->d_off = (offset_t)tdp->td_offset + 1;
1539                         dp = (struct dirent64 *)
1540                             ((uintptr_t)dp + dp->d_reclen);
1541                         outcount += reclen;
1542                         ASSERT(outcount <= bufsize);
1543                 }
1544                 tdp = tdp->td_next;
1545         }
1546 
1547         if (!error)
1548                 error = uiomove(outbuf, outcount, UIO_READ, uiop);
1549 
1550         if (!error) {
1551                 /* If we reached the end of the list our offset */
1552                 /* should now be just past the end. */
1553                 if (!tdp) {
1554                         offset += 1;
1555                         if (eofp)
1556                                 *eofp = 1;
1557                 } else if (eofp)
1558                         *eofp = 0;
1559                 uiop->uio_offset = offset;
1560         }
1561         gethrestime(&tp->tn_atime);
1562         kmem_free(outbuf, bufsize);
1563         return (error);
1564 }
1565 
1566 /* ARGSUSED5 */
1567 static int
1568 tmp_symlink(
1569         struct vnode *dvp,
1570         char *lnm,
1571         struct vattr *tva,
1572         char *tnm,
1573         struct cred *cred,
1574         caller_context_t *ct,
1575         int flags)
1576 {
1577         struct tmpnode *parent = (struct tmpnode *)VTOTN(dvp);
1578         struct tmpnode *self = (struct tmpnode *)NULL;
1579         struct tmount *tm = (struct tmount *)VTOTM(dvp);
1580         char *cp = NULL;
1581         int error;
1582         size_t len;
1583 
1584         /* no symlinks allowed to files in xattr dirs */
1585         if (parent->tn_flags & ISXATTR)
1586                 return (EINVAL);
1587 
1588         error = tdirlookup(parent, lnm, &self, cred);
1589         if (error == 0) {
1590                 /*
1591                  * The entry already exists
1592                  */
1593                 tmpnode_rele(self);
1594                 return (EEXIST);        /* was 0 */
1595         }
1596 
1597         if (error != ENOENT) {
1598                 if (self != NULL)
1599                         tmpnode_rele(self);
1600                 return (error);
1601         }
1602 
1603         rw_enter(&parent->tn_rwlock, RW_WRITER);
1604         error = tdirenter(tm, parent, lnm, DE_CREATE, (struct tmpnode *)NULL,
1605             (struct tmpnode *)NULL, tva, &self, cred, ct);
1606         rw_exit(&parent->tn_rwlock);
1607 
1608         if (error) {
1609                 if (self)
1610                         tmpnode_rele(self);
1611                 return (error);
1612         }
1613         len = strlen(tnm) + 1;
1614         cp = tmp_memalloc(len, 0);
1615         if (cp == NULL) {
1616                 tmpnode_rele(self);
1617                 return (ENOSPC);
1618         }
1619         (void) strcpy(cp, tnm);
1620 
1621         self->tn_symlink = cp;
1622         self->tn_size = len - 1;
1623         tmpnode_rele(self);
1624         return (error);
1625 }
1626 
1627 /* ARGSUSED2 */
1628 static int
1629 tmp_readlink(
1630         struct vnode *vp,
1631         struct uio *uiop,
1632         struct cred *cred,
1633         caller_context_t *ct)
1634 {
1635         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
1636         int error = 0;
1637 
1638         if (vp->v_type != VLNK)
1639                 return (EINVAL);
1640 
1641         rw_enter(&tp->tn_rwlock, RW_READER);
1642         rw_enter(&tp->tn_contents, RW_READER);
1643         error = uiomove(tp->tn_symlink, tp->tn_size, UIO_READ, uiop);
1644         gethrestime(&tp->tn_atime);
1645         rw_exit(&tp->tn_contents);
1646         rw_exit(&tp->tn_rwlock);
1647         return (error);
1648 }
1649 
1650 /* ARGSUSED */
1651 static int
1652 tmp_fsync(
1653         struct vnode *vp,
1654         int syncflag,
1655         struct cred *cred,
1656         caller_context_t *ct)
1657 {
1658         return (0);
1659 }
1660 
1661 /* ARGSUSED */
1662 static void
1663 tmp_inactive(struct vnode *vp, struct cred *cred, caller_context_t *ct)
1664 {
1665         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
1666         struct tmount *tm = (struct tmount *)VFSTOTM(vp->v_vfsp);
1667 
1668         rw_enter(&tp->tn_rwlock, RW_WRITER);
1669 top:
1670         mutex_enter(&tp->tn_tlock);
1671         mutex_enter(&vp->v_lock);
1672         ASSERT(vp->v_count >= 1);
1673 
1674         /*
1675          * If we don't have the last hold or the link count is non-zero,
1676          * there's little to do -- just drop our hold.
1677          */
1678         if (vp->v_count > 1 || tp->tn_nlink != 0) {
1679                 vp->v_count--;
1680                 mutex_exit(&vp->v_lock);
1681                 mutex_exit(&tp->tn_tlock);
1682                 rw_exit(&tp->tn_rwlock);
1683                 return;
1684         }
1685 
1686         /*
1687          * We have the last hold *and* the link count is zero, so this
1688          * tmpnode is dead from the filesystem's viewpoint.  However,
1689          * if the tmpnode has any pages associated with it (i.e. if it's
1690          * a normal file with non-zero size), the tmpnode can still be
1691          * discovered by pageout or fsflush via the page vnode pointers.
1692          * In this case we must drop all our locks, truncate the tmpnode,
1693          * and try the whole dance again.
1694          */
1695         if (tp->tn_size != 0) {
1696                 if (tp->tn_type == VREG) {
1697                         mutex_exit(&vp->v_lock);
1698                         mutex_exit(&tp->tn_tlock);
1699                         rw_enter(&tp->tn_contents, RW_WRITER);
1700                         (void) tmpnode_trunc(tm, tp, 0);
1701                         rw_exit(&tp->tn_contents);
1702                         ASSERT(tp->tn_size == 0);
1703                         ASSERT(tp->tn_nblocks == 0);
1704                         goto top;
1705                 }
1706                 if (tp->tn_type == VLNK)
1707                         tmp_memfree(tp->tn_symlink, tp->tn_size + 1);
1708         }
1709 
1710         /*
1711          * Remove normal file/dir's xattr dir and xattrs.
1712          */
1713         if (tp->tn_xattrdp) {
1714                 struct tmpnode *xtp = tp->tn_xattrdp;
1715 
1716                 ASSERT(xtp->tn_flags & ISXATTR);
1717                 tmpnode_hold(xtp);
1718                 rw_enter(&xtp->tn_rwlock, RW_WRITER);
1719                 tdirtrunc(xtp);
1720                 DECR_COUNT(&xtp->tn_nlink, &xtp->tn_tlock);
1721                 tp->tn_xattrdp = NULL;
1722                 rw_exit(&xtp->tn_rwlock);
1723                 tmpnode_rele(xtp);
1724         }
1725 
1726         mutex_exit(&vp->v_lock);
1727         mutex_exit(&tp->tn_tlock);
1728         /* Here's our chance to send invalid event while we're between locks */
1729         vn_invalid(TNTOV(tp));
1730         mutex_enter(&tm->tm_contents);
1731         if (tp->tn_forw == NULL)
1732                 tm->tm_rootnode->tn_back = tp->tn_back;
1733         else
1734                 tp->tn_forw->tn_back = tp->tn_back;
1735         tp->tn_back->tn_forw = tp->tn_forw;
1736         mutex_exit(&tm->tm_contents);
1737         rw_exit(&tp->tn_rwlock);
1738         rw_destroy(&tp->tn_rwlock);
1739         mutex_destroy(&tp->tn_tlock);
1740         vn_free(TNTOV(tp));
1741         tmp_memfree(tp, sizeof (struct tmpnode));
1742 }
1743 
1744 /* ARGSUSED2 */
1745 static int
1746 tmp_fid(struct vnode *vp, struct fid *fidp, caller_context_t *ct)
1747 {
1748         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
1749         struct tfid *tfid;
1750 
1751         if (fidp->fid_len < (sizeof (struct tfid) - sizeof (ushort_t))) {
1752                 fidp->fid_len = sizeof (struct tfid) - sizeof (ushort_t);
1753                 return (ENOSPC);
1754         }
1755 
1756         tfid = (struct tfid *)fidp;
1757         bzero(tfid, sizeof (struct tfid));
1758         tfid->tfid_len = (int)sizeof (struct tfid) - sizeof (ushort_t);
1759 
1760         tfid->tfid_ino = tp->tn_nodeid;
1761         tfid->tfid_gen = tp->tn_gen;
1762 
1763         return (0);
1764 }
1765 
1766 
1767 /*
1768  * Return all the pages from [off..off+len] in given file
1769  */
1770 /* ARGSUSED */
1771 static int
1772 tmp_getpage(
1773         struct vnode *vp,
1774         offset_t off,
1775         size_t len,
1776         uint_t *protp,
1777         page_t *pl[],
1778         size_t plsz,
1779         struct seg *seg,
1780         caddr_t addr,
1781         enum seg_rw rw,
1782         struct cred *cr,
1783         caller_context_t *ct)
1784 {
1785         int err = 0;
1786         struct tmpnode *tp = VTOTN(vp);
1787         anoff_t toff = (anoff_t)off;
1788         size_t tlen = len;
1789         u_offset_t tmpoff;
1790         timestruc_t now;
1791 
1792         rw_enter(&tp->tn_contents, RW_READER);
1793 
1794         if (off + len  > tp->tn_size + PAGEOFFSET) {
1795                 err = EFAULT;
1796                 goto out;
1797         }
1798         /*
1799          * Look for holes (no anon slot) in faulting range. If there are
1800          * holes we have to switch to a write lock and fill them in. Swap
1801          * space for holes was already reserved when the file was grown.
1802          */
1803         tmpoff = toff;
1804         if (non_anon(tp->tn_anon, btop(off), &tmpoff, &tlen)) {
1805                 if (!rw_tryupgrade(&tp->tn_contents)) {
1806                         rw_exit(&tp->tn_contents);
1807                         rw_enter(&tp->tn_contents, RW_WRITER);
1808                         /* Size may have changed when lock was dropped */
1809                         if (off + len  > tp->tn_size + PAGEOFFSET) {
1810                                 err = EFAULT;
1811                                 goto out;
1812                         }
1813                 }
1814                 for (toff = (anoff_t)off; toff < (anoff_t)off + len;
1815                     toff += PAGESIZE) {
1816                         if (anon_get_ptr(tp->tn_anon, btop(toff)) == NULL) {
1817                                 /* XXX - may allocate mem w. write lock held */
1818                                 (void) anon_set_ptr(tp->tn_anon, btop(toff),
1819                                     anon_alloc(vp, toff), ANON_SLEEP);
1820                                 tp->tn_nblocks++;
1821                         }
1822                 }
1823                 rw_downgrade(&tp->tn_contents);
1824         }
1825 
1826 
1827         err = pvn_getpages(tmp_getapage, vp, (u_offset_t)off, len, protp,
1828             pl, plsz, seg, addr, rw, cr);
1829 
1830         gethrestime(&now);
1831         tp->tn_atime = now;
1832         if (rw == S_WRITE)
1833                 tp->tn_mtime = now;
1834 
1835 out:
1836         rw_exit(&tp->tn_contents);
1837         return (err);
1838 }
1839 
1840 /*
1841  * Called from pvn_getpages to get a particular page.
1842  */
1843 /*ARGSUSED*/
1844 static int
1845 tmp_getapage(
1846         struct vnode *vp,
1847         u_offset_t off,
1848         size_t len,
1849         uint_t *protp,
1850         page_t *pl[],
1851         size_t plsz,
1852         struct seg *seg,
1853         caddr_t addr,
1854         enum seg_rw rw,
1855         struct cred *cr)
1856 {
1857         struct page *pp;
1858         int flags;
1859         int err = 0;
1860         struct vnode *pvp;
1861         u_offset_t poff;
1862 
1863         if (protp != NULL)
1864                 *protp = PROT_ALL;
1865 again:
1866         if (pp = page_lookup(vp, off, rw == S_CREATE ? SE_EXCL : SE_SHARED)) {
1867                 if (pl) {
1868                         pl[0] = pp;
1869                         pl[1] = NULL;
1870                 } else {
1871                         page_unlock(pp);
1872                 }
1873         } else {
1874                 pp = page_create_va(vp, off, PAGESIZE,
1875                     PG_WAIT | PG_EXCL, seg, addr);
1876                 /*
1877                  * Someone raced in and created the page after we did the
1878                  * lookup but before we did the create, so go back and
1879                  * try to look it up again.
1880                  */
1881                 if (pp == NULL)
1882                         goto again;
1883                 /*
1884                  * Fill page from backing store, if any. If none, then
1885                  * either this is a newly filled hole or page must have
1886                  * been unmodified and freed so just zero it out.
1887                  */
1888                 err = swap_getphysname(vp, off, &pvp, &poff);
1889                 if (err) {
1890                         panic("tmp_getapage: no anon slot vp %p "
1891                             "off %llx pp %p\n", (void *)vp, off, (void *)pp);
1892                 }
1893                 if (pvp) {
1894                         flags = (pl == NULL ? B_ASYNC|B_READ : B_READ);
1895                         err = VOP_PAGEIO(pvp, pp, (u_offset_t)poff, PAGESIZE,
1896                             flags, cr, NULL);
1897                         if (flags & B_ASYNC)
1898                                 pp = NULL;
1899                 } else if (rw != S_CREATE) {
1900                         pagezero(pp, 0, PAGESIZE);
1901                 }
1902                 if (err && pp)
1903                         pvn_read_done(pp, B_ERROR);
1904                 if (err == 0) {
1905                         if (pl)
1906                                 pvn_plist_init(pp, pl, plsz, off, PAGESIZE, rw);
1907                         else
1908                                 pvn_io_done(pp);
1909                 }
1910         }
1911         return (err);
1912 }
1913 
1914 
1915 /*
1916  * Flags are composed of {B_INVAL, B_DIRTY B_FREE, B_DONTNEED}.
1917  * If len == 0, do from off to EOF.
1918  */
1919 static int tmp_nopage = 0;      /* Don't do tmp_putpage's if set */
1920 
1921 /* ARGSUSED */
1922 int
1923 tmp_putpage(
1924         register struct vnode *vp,
1925         offset_t off,
1926         size_t len,
1927         int flags,
1928         struct cred *cr,
1929         caller_context_t *ct)
1930 {
1931         register page_t *pp;
1932         u_offset_t io_off;
1933         size_t io_len = 0;
1934         int err = 0;
1935         struct tmpnode *tp = VTOTN(vp);
1936         int dolock;
1937 
1938         if (tmp_nopage)
1939                 return (0);
1940 
1941         ASSERT(vp->v_count != 0);
1942 
1943         if (vp->v_flag & VNOMAP)
1944                 return (ENOSYS);
1945 
1946         /*
1947          * This being tmpfs, we don't ever do i/o unless we really
1948          * have to (when we're low on memory and pageout calls us
1949          * with B_ASYNC | B_FREE or the user explicitly asks for it with
1950          * B_DONTNEED).
1951          * XXX to approximately track the mod time like ufs we should
1952          * update the times here. The problem is, once someone does a
1953          * store we never clear the mod bit and do i/o, thus fsflush
1954          * will keep calling us every 30 seconds to do the i/o and we'll
1955          * continually update the mod time. At least we update the mod
1956          * time on the first store because this results in a call to getpage.
1957          */
1958         if (flags != (B_ASYNC | B_FREE) && (flags & B_INVAL) == 0 &&
1959             (flags & B_DONTNEED) == 0)
1960                 return (0);
1961         /*
1962          * If this thread owns the lock, i.e., this thread grabbed it
1963          * as writer somewhere above, then we don't need to grab the
1964          * lock as reader in this routine.
1965          */
1966         dolock = (rw_owner(&tp->tn_contents) != curthread);
1967 
1968         /*
1969          * If this is pageout don't block on the lock as you could deadlock
1970          * when freemem == 0 (another thread has the read lock and is blocked
1971          * creating a page, and a third thread is waiting to get the writers
1972          * lock - waiting writers priority blocks us from getting the read
1973          * lock). Of course, if the only freeable pages are on this tmpnode
1974          * we're hosed anyways. A better solution might be a new lock type.
1975          * Note: ufs has the same problem.
1976          */
1977         if (curproc == proc_pageout) {
1978                 if (!rw_tryenter(&tp->tn_contents, RW_READER))
1979                         return (ENOMEM);
1980         } else if (dolock)
1981                 rw_enter(&tp->tn_contents, RW_READER);
1982 
1983         if (!vn_has_cached_data(vp))
1984                 goto out;
1985 
1986         if (len == 0) {
1987                 if (curproc == proc_pageout) {
1988                         panic("tmp: pageout can't block");
1989                         /*NOTREACHED*/
1990                 }
1991 
1992                 /* Search the entire vp list for pages >= off. */
1993                 err = pvn_vplist_dirty(vp, (u_offset_t)off, tmp_putapage,
1994                     flags, cr);
1995         } else {
1996                 u_offset_t eoff;
1997 
1998                 /*
1999                  * Loop over all offsets in the range [off...off + len]
2000                  * looking for pages to deal with.
2001                  */
2002                 eoff = MIN(off + len, tp->tn_size);
2003                 for (io_off = off; io_off < eoff; io_off += io_len) {
2004                         /*
2005                          * If we are not invalidating, synchronously
2006                          * freeing or writing pages use the routine
2007                          * page_lookup_nowait() to prevent reclaiming
2008                          * them from the free list.
2009                          */
2010                         if ((flags & B_INVAL) || ((flags & B_ASYNC) == 0)) {
2011                                 pp = page_lookup(vp, io_off,
2012                                     (flags & (B_INVAL | B_FREE)) ?
2013                                     SE_EXCL : SE_SHARED);
2014                         } else {
2015                                 pp = page_lookup_nowait(vp, io_off,
2016                                     (flags & B_FREE) ? SE_EXCL : SE_SHARED);
2017                         }
2018 
2019                         if (pp == NULL || pvn_getdirty(pp, flags) == 0)
2020                                 io_len = PAGESIZE;
2021                         else {
2022                                 err = tmp_putapage(vp, pp, &io_off, &io_len,
2023                                     flags, cr);
2024                                 if (err != 0)
2025                                         break;
2026                         }
2027                 }
2028         }
2029         /* If invalidating, verify all pages on vnode list are gone. */
2030         if (err == 0 && off == 0 && len == 0 &&
2031             (flags & B_INVAL) && vn_has_cached_data(vp)) {
2032                 panic("tmp_putpage: B_INVAL, pages not gone");
2033                 /*NOTREACHED*/
2034         }
2035 out:
2036         if ((curproc == proc_pageout) || dolock)
2037                 rw_exit(&tp->tn_contents);
2038         /*
2039          * Only reason putapage is going to give us SE_NOSWAP as error
2040          * is when we ask a page to be written to physical backing store
2041          * and there is none. Ignore this because we might be dealing
2042          * with a swap page which does not have any backing store
2043          * on disk. In any other case we won't get this error over here.
2044          */
2045         if (err == SE_NOSWAP)
2046                 err = 0;
2047         return (err);
2048 }
2049 
2050 long tmp_putpagecnt, tmp_pagespushed;
2051 
2052 /*
2053  * Write out a single page.
2054  * For tmpfs this means choose a physical swap slot and write the page
2055  * out using VOP_PAGEIO. For performance, we attempt to kluster; i.e.,
2056  * we try to find a bunch of other dirty pages adjacent in the file
2057  * and a bunch of contiguous swap slots, and then write all the pages
2058  * out in a single i/o.
2059  */
2060 /*ARGSUSED*/
2061 static int
2062 tmp_putapage(
2063         struct vnode *vp,
2064         page_t *pp,
2065         u_offset_t *offp,
2066         size_t *lenp,
2067         int flags,
2068         struct cred *cr)
2069 {
2070         int err;
2071         ulong_t klstart, kllen;
2072         page_t *pplist, *npplist;
2073         extern int klustsize;
2074         long tmp_klustsize;
2075         struct tmpnode *tp;
2076         size_t pp_off, pp_len;
2077         u_offset_t io_off;
2078         size_t io_len;
2079         struct vnode *pvp;
2080         u_offset_t pstart;
2081         u_offset_t offset;
2082         u_offset_t tmpoff;
2083 
2084         ASSERT(PAGE_LOCKED(pp));
2085 
2086         /* Kluster in tmp_klustsize chunks */
2087         tp = VTOTN(vp);
2088         tmp_klustsize = klustsize;
2089         offset = pp->p_offset;
2090         klstart = (offset / tmp_klustsize) * tmp_klustsize;
2091         kllen = MIN(tmp_klustsize, tp->tn_size - klstart);
2092 
2093         /* Get a kluster of pages */
2094         pplist =
2095             pvn_write_kluster(vp, pp, &tmpoff, &pp_len, klstart, kllen, flags);
2096 
2097         pp_off = (size_t)tmpoff;
2098 
2099         /*
2100          * Get a cluster of physical offsets for the pages; the amount we
2101          * get may be some subrange of what we ask for (io_off, io_len).
2102          */
2103         io_off = pp_off;
2104         io_len = pp_len;
2105         err = swap_newphysname(vp, offset, &io_off, &io_len, &pvp, &pstart);
2106         ASSERT(err != SE_NOANON); /* anon slot must have been filled */
2107         if (err) {
2108                 pvn_write_done(pplist, B_ERROR | B_WRITE | flags);
2109                 /*
2110                  * If this routine is called as a result of segvn_sync
2111                  * operation and we have no physical swap then we can get an
2112                  * error here. In such case we would return SE_NOSWAP as error.
2113                  * At this point, we expect only SE_NOSWAP.
2114                  */
2115                 ASSERT(err == SE_NOSWAP);
2116                 if (flags & B_INVAL)
2117                         err = ENOMEM;
2118                 goto out;
2119         }
2120         ASSERT(pp_off <= io_off && io_off + io_len <= pp_off + pp_len);
2121         ASSERT(io_off <= offset && offset < io_off + io_len);
2122 
2123         /* Toss pages at front/rear that we couldn't get physical backing for */
2124         if (io_off != pp_off) {
2125                 npplist = NULL;
2126                 page_list_break(&pplist, &npplist, btop(io_off - pp_off));
2127                 ASSERT(pplist->p_offset == pp_off);
2128                 ASSERT(pplist->p_prev->p_offset == io_off - PAGESIZE);
2129                 pvn_write_done(pplist, B_ERROR | B_WRITE | flags);
2130                 pplist = npplist;
2131         }
2132         if (io_off + io_len < pp_off + pp_len) {
2133                 npplist = NULL;
2134                 page_list_break(&pplist, &npplist, btop(io_len));
2135                 ASSERT(npplist->p_offset == io_off + io_len);
2136                 ASSERT(npplist->p_prev->p_offset == pp_off + pp_len - PAGESIZE);
2137                 pvn_write_done(npplist, B_ERROR | B_WRITE | flags);
2138         }
2139 
2140         ASSERT(pplist->p_offset == io_off);
2141         ASSERT(pplist->p_prev->p_offset == io_off + io_len - PAGESIZE);
2142         ASSERT(btopr(io_len) <= btopr(kllen));
2143 
2144         /* Do i/o on the remaining kluster */
2145         err = VOP_PAGEIO(pvp, pplist, (u_offset_t)pstart, io_len,
2146             B_WRITE | flags, cr, NULL);
2147 
2148         if ((flags & B_ASYNC) == 0) {
2149                 pvn_write_done(pplist, ((err) ? B_ERROR : 0) | B_WRITE | flags);
2150         }
2151 out:
2152         if (!err) {
2153                 if (offp)
2154                         *offp = io_off;
2155                 if (lenp)
2156                         *lenp = io_len;
2157                 tmp_putpagecnt++;
2158                 tmp_pagespushed += btop(io_len);
2159         }
2160         if (err && err != ENOMEM && err != SE_NOSWAP)
2161                 cmn_err(CE_WARN, "tmp_putapage: err %d\n", err);
2162         return (err);
2163 }
2164 
2165 /* ARGSUSED */
2166 static int
2167 tmp_map(
2168         struct vnode *vp,
2169         offset_t off,
2170         struct as *as,
2171         caddr_t *addrp,
2172         size_t len,
2173         uchar_t prot,
2174         uchar_t maxprot,
2175         uint_t flags,
2176         struct cred *cred,
2177         caller_context_t *ct)
2178 {
2179         struct segvn_crargs vn_a;
2180         struct tmpnode *tp = (struct tmpnode *)VTOTN(vp);
2181         int error;
2182 
2183 #ifdef _ILP32
2184         if (len > MAXOFF_T)
2185                 return (ENOMEM);
2186 #endif
2187 
2188         if (vp->v_flag & VNOMAP)
2189                 return (ENOSYS);
2190 
2191         if (off < 0 || (offset_t)(off + len) < 0 ||
2192             off > MAXOFF_T || (off + len) > MAXOFF_T)
2193                 return (ENXIO);
2194 
2195         if (vp->v_type != VREG)
2196                 return (ENODEV);
2197 
2198         /*
2199          * Don't allow mapping to locked file
2200          */
2201         if (vn_has_mandatory_locks(vp, tp->tn_mode)) {
2202                 return (EAGAIN);
2203         }
2204 
2205         as_rangelock(as);
2206         error = choose_addr(as, addrp, len, off, ADDR_VACALIGN, flags);
2207         if (error != 0) {
2208                 as_rangeunlock(as);
2209                 return (error);
2210         }
2211 
2212         vn_a.vp = vp;
2213         vn_a.offset = (u_offset_t)off;
2214         vn_a.type = flags & MAP_TYPE;
2215         vn_a.prot = prot;
2216         vn_a.maxprot = maxprot;
2217         vn_a.flags = flags & ~MAP_TYPE;
2218         vn_a.cred = cred;
2219         vn_a.amp = NULL;
2220         vn_a.szc = 0;
2221         vn_a.lgrp_mem_policy_flags = 0;
2222 
2223         error = as_map(as, *addrp, len, segvn_create, &vn_a);
2224         as_rangeunlock(as);
2225         return (error);
2226 }
2227 
2228 /*
2229  * tmp_addmap and tmp_delmap can't be called since the vp
2230  * maintained in the segvn mapping is NULL.
2231  */
2232 /* ARGSUSED */
2233 static int
2234 tmp_addmap(
2235         struct vnode *vp,
2236         offset_t off,
2237         struct as *as,
2238         caddr_t addr,
2239         size_t len,
2240         uchar_t prot,
2241         uchar_t maxprot,
2242         uint_t flags,
2243         struct cred *cred,
2244         caller_context_t *ct)
2245 {
2246         return (0);
2247 }
2248 
2249 /* ARGSUSED */
2250 static int
2251 tmp_delmap(
2252         struct vnode *vp,
2253         offset_t off,
2254         struct as *as,
2255         caddr_t addr,
2256         size_t len,
2257         uint_t prot,
2258         uint_t maxprot,
2259         uint_t flags,
2260         struct cred *cred,
2261         caller_context_t *ct)
2262 {
2263         return (0);
2264 }
2265 
2266 static int
2267 tmp_freesp(struct vnode *vp, struct flock64 *lp, int flag)
2268 {
2269         register int i;
2270         register struct tmpnode *tp = VTOTN(vp);
2271         int error;
2272 
2273         ASSERT(vp->v_type == VREG);
2274         ASSERT(lp->l_start >= 0);
2275 
2276         if (lp->l_len != 0)
2277                 return (EINVAL);
2278 
2279         rw_enter(&tp->tn_rwlock, RW_WRITER);
2280         if (tp->tn_size == lp->l_start) {
2281                 rw_exit(&tp->tn_rwlock);
2282                 return (0);
2283         }
2284 
2285         /*
2286          * Check for any mandatory locks on the range
2287          */
2288         if (MANDLOCK(vp, tp->tn_mode)) {
2289                 long save_start;
2290 
2291                 save_start = lp->l_start;
2292 
2293                 if (tp->tn_size < lp->l_start) {
2294                         /*
2295                          * "Truncate up" case: need to make sure there
2296                          * is no lock beyond current end-of-file. To
2297                          * do so, we need to set l_start to the size
2298                          * of the file temporarily.
2299                          */
2300                         lp->l_start = tp->tn_size;
2301                 }
2302                 lp->l_type = F_WRLCK;
2303                 lp->l_sysid = 0;
2304                 lp->l_pid = ttoproc(curthread)->p_pid;
2305                 i = (flag & (FNDELAY|FNONBLOCK)) ? 0 : SLPFLCK;
2306                 if ((i = reclock(vp, lp, i, 0, lp->l_start, NULL)) != 0 ||
2307                     lp->l_type != F_UNLCK) {
2308                         rw_exit(&tp->tn_rwlock);
2309                         return (i ? i : EAGAIN);
2310                 }
2311 
2312                 lp->l_start = save_start;
2313         }
2314         VFSTOTM(vp->v_vfsp);
2315 
2316         rw_enter(&tp->tn_contents, RW_WRITER);
2317         error = tmpnode_trunc((struct tmount *)VFSTOTM(vp->v_vfsp),
2318             tp, (ulong_t)lp->l_start);
2319         rw_exit(&tp->tn_contents);
2320         rw_exit(&tp->tn_rwlock);
2321         return (error);
2322 }
2323 
2324 /* ARGSUSED */
2325 static int
2326 tmp_space(
2327         struct vnode *vp,
2328         int cmd,
2329         struct flock64 *bfp,
2330         int flag,
2331         offset_t offset,
2332         cred_t *cred,
2333         caller_context_t *ct)
2334 {
2335         int error;
2336 
2337         if (cmd != F_FREESP)
2338                 return (EINVAL);
2339         if ((error = convoff(vp, bfp, 0, (offset_t)offset)) == 0) {
2340                 if ((bfp->l_start > MAXOFF_T) || (bfp->l_len > MAXOFF_T))
2341                         return (EFBIG);
2342                 error = tmp_freesp(vp, bfp, flag);
2343 
2344                 if (error == 0 && bfp->l_start == 0)
2345                         vnevent_truncate(vp, ct);
2346         }
2347         return (error);
2348 }
2349 
2350 /* ARGSUSED */
2351 static int
2352 tmp_seek(
2353         struct vnode *vp,
2354         offset_t ooff,
2355         offset_t *noffp,
2356         caller_context_t *ct)
2357 {
2358         return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0);
2359 }
2360 
2361 /* ARGSUSED2 */
2362 static int
2363 tmp_rwlock(struct vnode *vp, int write_lock, caller_context_t *ctp)
2364 {
2365         struct tmpnode *tp = VTOTN(vp);
2366 
2367         if (write_lock) {
2368                 rw_enter(&tp->tn_rwlock, RW_WRITER);
2369         } else {
2370                 rw_enter(&tp->tn_rwlock, RW_READER);
2371         }
2372         return (write_lock);
2373 }
2374 
2375 /* ARGSUSED1 */
2376 static void
2377 tmp_rwunlock(struct vnode *vp, int write_lock, caller_context_t *ctp)
2378 {
2379         struct tmpnode *tp = VTOTN(vp);
2380 
2381         rw_exit(&tp->tn_rwlock);
2382 }
2383 
2384 static int
2385 tmp_pathconf(
2386         struct vnode *vp,
2387         int cmd,
2388         ulong_t *valp,
2389         cred_t *cr,
2390         caller_context_t *ct)
2391 {
2392         struct tmpnode *tp = NULL;
2393         int error;
2394 
2395         switch (cmd) {
2396         case _PC_XATTR_EXISTS:
2397                 if (vp->v_vfsp->vfs_flag & VFS_XATTR) {
2398                         *valp = 0;      /* assume no attributes */
2399                         error = 0;      /* okay to ask */
2400                         tp = VTOTN(vp);
2401                         rw_enter(&tp->tn_rwlock, RW_READER);
2402                         if (tp->tn_xattrdp) {
2403                                 rw_enter(&tp->tn_xattrdp->tn_rwlock, RW_READER);
2404                                 /* do not count "." and ".." */
2405                                 if (tp->tn_xattrdp->tn_dirents > 2)
2406                                         *valp = 1;
2407                                 rw_exit(&tp->tn_xattrdp->tn_rwlock);
2408                         }
2409                         rw_exit(&tp->tn_rwlock);
2410                 } else {
2411                         error = EINVAL;
2412                 }
2413                 break;
2414         case _PC_SATTR_ENABLED:
2415         case _PC_SATTR_EXISTS:
2416                 *valp = vfs_has_feature(vp->v_vfsp, VFSFT_SYSATTR_VIEWS) &&
2417                     (vp->v_type == VREG || vp->v_type == VDIR);
2418                 error = 0;
2419                 break;
2420         case _PC_TIMESTAMP_RESOLUTION:
2421                 /* nanosecond timestamp resolution */
2422                 *valp = 1L;
2423                 error = 0;
2424                 break;
2425         default:
2426                 error = fs_pathconf(vp, cmd, valp, cr, ct);
2427         }
2428         return (error);
2429 }
2430 
2431 
2432 struct vnodeops *tmp_vnodeops;
2433 
2434 const fs_operation_def_t tmp_vnodeops_template[] = {
2435         VOPNAME_OPEN,           { .vop_open = tmp_open },
2436         VOPNAME_CLOSE,          { .vop_close = tmp_close },
2437         VOPNAME_READ,           { .vop_read = tmp_read },
2438         VOPNAME_WRITE,          { .vop_write = tmp_write },
2439         VOPNAME_IOCTL,          { .vop_ioctl = tmp_ioctl },
2440         VOPNAME_GETATTR,        { .vop_getattr = tmp_getattr },
2441         VOPNAME_SETATTR,        { .vop_setattr = tmp_setattr },
2442         VOPNAME_ACCESS,         { .vop_access = tmp_access },
2443         VOPNAME_LOOKUP,         { .vop_lookup = tmp_lookup },
2444         VOPNAME_CREATE,         { .vop_create = tmp_create },
2445         VOPNAME_REMOVE,         { .vop_remove = tmp_remove },
2446         VOPNAME_LINK,           { .vop_link = tmp_link },
2447         VOPNAME_RENAME,         { .vop_rename = tmp_rename },
2448         VOPNAME_MKDIR,          { .vop_mkdir = tmp_mkdir },
2449         VOPNAME_RMDIR,          { .vop_rmdir = tmp_rmdir },
2450         VOPNAME_READDIR,        { .vop_readdir = tmp_readdir },
2451         VOPNAME_SYMLINK,        { .vop_symlink = tmp_symlink },
2452         VOPNAME_READLINK,       { .vop_readlink = tmp_readlink },
2453         VOPNAME_FSYNC,          { .vop_fsync = tmp_fsync },
2454         VOPNAME_INACTIVE,       { .vop_inactive = tmp_inactive },
2455         VOPNAME_FID,            { .vop_fid = tmp_fid },
2456         VOPNAME_RWLOCK,         { .vop_rwlock = tmp_rwlock },
2457         VOPNAME_RWUNLOCK,       { .vop_rwunlock = tmp_rwunlock },
2458         VOPNAME_SEEK,           { .vop_seek = tmp_seek },
2459         VOPNAME_SPACE,          { .vop_space = tmp_space },
2460         VOPNAME_GETPAGE,        { .vop_getpage = tmp_getpage },
2461         VOPNAME_PUTPAGE,        { .vop_putpage = tmp_putpage },
2462         VOPNAME_MAP,            { .vop_map = tmp_map },
2463         VOPNAME_ADDMAP,         { .vop_addmap = tmp_addmap },
2464         VOPNAME_DELMAP,         { .vop_delmap = tmp_delmap },
2465         VOPNAME_PATHCONF,       { .vop_pathconf = tmp_pathconf },
2466         VOPNAME_VNEVENT,        { .vop_vnevent = fs_vnevent_support },
2467         NULL,                   NULL
2468 };