The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/nfsclient/nfs_subs.c

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    1 /*-
    2  * Copyright (c) 1989, 1993
    3  *      The Regents of the University of California.  All rights reserved.
    4  *
    5  * This code is derived from software contributed to Berkeley by
    6  * Rick Macklem at The University of Guelph.
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions
   10  * are met:
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  * 4. Neither the name of the University nor the names of its contributors
   17  *    may be used to endorse or promote products derived from this software
   18  *    without specific prior written permission.
   19  *
   20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   30  * SUCH DAMAGE.
   31  *
   32  *      @(#)nfs_subs.c  8.8 (Berkeley) 5/22/95
   33  */
   34 
   35 #include <sys/cdefs.h>
   36 __FBSDID("$FreeBSD: releng/6.3/sys/nfsclient/nfs_subs.c 172724 2007-10-17 16:07:10Z jhb $");
   37 
   38 /*
   39  * These functions support the macros and help fiddle mbuf chains for
   40  * the nfs op functions. They do things like create the rpc header and
   41  * copy data between mbuf chains and uio lists.
   42  */
   43 
   44 #include <sys/param.h>
   45 #include <sys/systm.h>
   46 #include <sys/kernel.h>
   47 #include <sys/bio.h>
   48 #include <sys/buf.h>
   49 #include <sys/proc.h>
   50 #include <sys/mount.h>
   51 #include <sys/vnode.h>
   52 #include <sys/namei.h>
   53 #include <sys/mbuf.h>
   54 #include <sys/socket.h>
   55 #include <sys/stat.h>
   56 #include <sys/malloc.h>
   57 #include <sys/sysent.h>
   58 #include <sys/syscall.h>
   59 #include <sys/sysproto.h>
   60 
   61 #include <vm/vm.h>
   62 #include <vm/vm_object.h>
   63 #include <vm/vm_extern.h>
   64 #include <vm/uma.h>
   65 
   66 #include <rpc/rpcclnt.h>
   67 
   68 #include <nfs/rpcv2.h>
   69 #include <nfs/nfsproto.h>
   70 #include <nfsclient/nfs.h>
   71 #include <nfsclient/nfsnode.h>
   72 #include <nfs/xdr_subs.h>
   73 #include <nfsclient/nfsm_subs.h>
   74 #include <nfsclient/nfsmount.h>
   75 
   76 #include <netinet/in.h>
   77 
   78 /*
   79  * Data items converted to xdr at startup, since they are constant
   80  * This is kinda hokey, but may save a little time doing byte swaps
   81  */
   82 u_int32_t       nfs_xdrneg1;
   83 u_int32_t       rpc_call, rpc_vers, rpc_reply, rpc_msgdenied, rpc_autherr,
   84                     rpc_mismatch, rpc_auth_unix, rpc_msgaccepted;
   85 u_int32_t       nfs_true, nfs_false;
   86 
   87 /* And other global data */
   88 u_int32_t nfs_xid = 0;
   89 static enum vtype nv2tov_type[8]= {
   90         VNON, VREG, VDIR, VBLK, VCHR, VLNK, VNON,  VNON
   91 };
   92 
   93 int             nfs_ticks;
   94 int             nfs_pbuf_freecnt = -1;  /* start out unlimited */
   95 
   96 struct nfs_reqq nfs_reqq;
   97 struct mtx nfs_reqq_mtx;
   98 struct mtx nfs_reply_mtx;
   99 struct nfs_bufq nfs_bufq;
  100 
  101 /*
  102  * and the reverse mapping from generic to Version 2 procedure numbers
  103  */
  104 int nfsv2_procid[NFS_NPROCS] = {
  105         NFSV2PROC_NULL,
  106         NFSV2PROC_GETATTR,
  107         NFSV2PROC_SETATTR,
  108         NFSV2PROC_LOOKUP,
  109         NFSV2PROC_NOOP,
  110         NFSV2PROC_READLINK,
  111         NFSV2PROC_READ,
  112         NFSV2PROC_WRITE,
  113         NFSV2PROC_CREATE,
  114         NFSV2PROC_MKDIR,
  115         NFSV2PROC_SYMLINK,
  116         NFSV2PROC_CREATE,
  117         NFSV2PROC_REMOVE,
  118         NFSV2PROC_RMDIR,
  119         NFSV2PROC_RENAME,
  120         NFSV2PROC_LINK,
  121         NFSV2PROC_READDIR,
  122         NFSV2PROC_NOOP,
  123         NFSV2PROC_STATFS,
  124         NFSV2PROC_NOOP,
  125         NFSV2PROC_NOOP,
  126         NFSV2PROC_NOOP,
  127         NFSV2PROC_NOOP,
  128 };
  129 
  130 LIST_HEAD(nfsnodehashhead, nfsnode);
  131 
  132 /*
  133  * Create the header for an rpc request packet
  134  * The hsiz is the size of the rest of the nfs request header.
  135  * (just used to decide if a cluster is a good idea)
  136  */
  137 struct mbuf *
  138 nfsm_reqhead(struct vnode *vp, u_long procid, int hsiz)
  139 {
  140         struct mbuf *mb;
  141 
  142         MGET(mb, M_TRYWAIT, MT_DATA);
  143         if (hsiz >= MINCLSIZE)
  144                 MCLGET(mb, M_TRYWAIT);
  145         mb->m_len = 0;
  146         return (mb);
  147 }
  148 
  149 /*
  150  * Build the RPC header and fill in the authorization info.
  151  * The authorization string argument is only used when the credentials
  152  * come from outside of the kernel.
  153  * Returns the head of the mbuf list.
  154  */
  155 struct mbuf *
  156 nfsm_rpchead(struct ucred *cr, int nmflag, int procid, int auth_type,
  157     int auth_len, struct mbuf *mrest, int mrest_len, struct mbuf **mbp,
  158     u_int32_t **xidpp)
  159 {
  160         struct mbuf *mb;
  161         u_int32_t *tl;
  162         caddr_t bpos;
  163         int i;
  164         struct mbuf *mreq;
  165         int grpsiz, authsiz;
  166 
  167         authsiz = nfsm_rndup(auth_len);
  168         MGETHDR(mb, M_TRYWAIT, MT_DATA);
  169         if ((authsiz + 10 * NFSX_UNSIGNED) >= MINCLSIZE) {
  170                 MCLGET(mb, M_TRYWAIT);
  171         } else if ((authsiz + 10 * NFSX_UNSIGNED) < MHLEN) {
  172                 MH_ALIGN(mb, authsiz + 10 * NFSX_UNSIGNED);
  173         } else {
  174                 MH_ALIGN(mb, 8 * NFSX_UNSIGNED);
  175         }
  176         mb->m_len = 0;
  177         mreq = mb;
  178         bpos = mtod(mb, caddr_t);
  179 
  180         /*
  181          * First the RPC header.
  182          */
  183         tl = nfsm_build(u_int32_t *, 8 * NFSX_UNSIGNED);
  184 
  185         /* Get a pretty random xid to start with */
  186         if (!nfs_xid)
  187                 nfs_xid = random();
  188         /*
  189          * Skip zero xid if it should ever happen.
  190          */
  191         if (++nfs_xid == 0)
  192                 nfs_xid++;
  193 
  194         *xidpp = tl;
  195         *tl++ = txdr_unsigned(nfs_xid);
  196         *tl++ = rpc_call;
  197         *tl++ = rpc_vers;
  198         *tl++ = txdr_unsigned(NFS_PROG);
  199         if (nmflag & NFSMNT_NFSV3) {
  200                 *tl++ = txdr_unsigned(NFS_VER3);
  201                 *tl++ = txdr_unsigned(procid);
  202         } else {
  203                 *tl++ = txdr_unsigned(NFS_VER2);
  204                 *tl++ = txdr_unsigned(nfsv2_procid[procid]);
  205         }
  206 
  207         /*
  208          * And then the authorization cred.
  209          */
  210         *tl++ = txdr_unsigned(auth_type);
  211         *tl = txdr_unsigned(authsiz);
  212         switch (auth_type) {
  213         case RPCAUTH_UNIX:
  214                 tl = nfsm_build(u_int32_t *, auth_len);
  215                 *tl++ = 0;              /* stamp ?? */
  216                 *tl++ = 0;              /* NULL hostname */
  217                 *tl++ = txdr_unsigned(cr->cr_uid);
  218                 *tl++ = txdr_unsigned(cr->cr_groups[0]);
  219                 grpsiz = (auth_len >> 2) - 5;
  220                 *tl++ = txdr_unsigned(grpsiz);
  221                 for (i = 1; i <= grpsiz; i++)
  222                         *tl++ = txdr_unsigned(cr->cr_groups[i]);
  223                 break;
  224         }
  225 
  226         /*
  227          * And the verifier...
  228          */
  229         tl = nfsm_build(u_int32_t *, 2 * NFSX_UNSIGNED);
  230         *tl++ = txdr_unsigned(RPCAUTH_NULL);
  231         *tl = 0;
  232         mb->m_next = mrest;
  233         mreq->m_pkthdr.len = authsiz + 10 * NFSX_UNSIGNED + mrest_len;
  234         mreq->m_pkthdr.rcvif = NULL;
  235         *mbp = mb;
  236         return (mreq);
  237 }
  238 
  239 /*
  240  * copies a uio scatter/gather list to an mbuf chain.
  241  * NOTE: can ony handle iovcnt == 1
  242  */
  243 int
  244 nfsm_uiotombuf(struct uio *uiop, struct mbuf **mq, int siz, caddr_t *bpos)
  245 {
  246         char *uiocp;
  247         struct mbuf *mp, *mp2;
  248         int xfer, left, mlen;
  249         int uiosiz, clflg, rem;
  250         char *cp;
  251 
  252 #ifdef DIAGNOSTIC
  253         if (uiop->uio_iovcnt != 1)
  254                 panic("nfsm_uiotombuf: iovcnt != 1");
  255 #endif
  256 
  257         if (siz > MLEN)         /* or should it >= MCLBYTES ?? */
  258                 clflg = 1;
  259         else
  260                 clflg = 0;
  261         rem = nfsm_rndup(siz)-siz;
  262         mp = mp2 = *mq;
  263         while (siz > 0) {
  264                 left = uiop->uio_iov->iov_len;
  265                 uiocp = uiop->uio_iov->iov_base;
  266                 if (left > siz)
  267                         left = siz;
  268                 uiosiz = left;
  269                 while (left > 0) {
  270                         mlen = M_TRAILINGSPACE(mp);
  271                         if (mlen == 0) {
  272                                 MGET(mp, M_TRYWAIT, MT_DATA);
  273                                 if (clflg)
  274                                         MCLGET(mp, M_TRYWAIT);
  275                                 mp->m_len = 0;
  276                                 mp2->m_next = mp;
  277                                 mp2 = mp;
  278                                 mlen = M_TRAILINGSPACE(mp);
  279                         }
  280                         xfer = (left > mlen) ? mlen : left;
  281 #ifdef notdef
  282                         /* Not Yet.. */
  283                         if (uiop->uio_iov->iov_op != NULL)
  284                                 (*(uiop->uio_iov->iov_op))
  285                                 (uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
  286                         else
  287 #endif
  288                         if (uiop->uio_segflg == UIO_SYSSPACE)
  289                                 bcopy(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
  290                         else
  291                                 copyin(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
  292                         mp->m_len += xfer;
  293                         left -= xfer;
  294                         uiocp += xfer;
  295                         uiop->uio_offset += xfer;
  296                         uiop->uio_resid -= xfer;
  297                 }
  298                 uiop->uio_iov->iov_base =
  299                     (char *)uiop->uio_iov->iov_base + uiosiz;
  300                 uiop->uio_iov->iov_len -= uiosiz;
  301                 siz -= uiosiz;
  302         }
  303         if (rem > 0) {
  304                 if (rem > M_TRAILINGSPACE(mp)) {
  305                         MGET(mp, M_TRYWAIT, MT_DATA);
  306                         mp->m_len = 0;
  307                         mp2->m_next = mp;
  308                 }
  309                 cp = mtod(mp, caddr_t)+mp->m_len;
  310                 for (left = 0; left < rem; left++)
  311                         *cp++ = '\0';
  312                 mp->m_len += rem;
  313                 *bpos = cp;
  314         } else
  315                 *bpos = mtod(mp, caddr_t)+mp->m_len;
  316         *mq = mp;
  317         return (0);
  318 }
  319 
  320 /*
  321  * Copy a string into mbufs for the hard cases...
  322  */
  323 int
  324 nfsm_strtmbuf(struct mbuf **mb, char **bpos, const char *cp, long siz)
  325 {
  326         struct mbuf *m1 = NULL, *m2;
  327         long left, xfer, len, tlen;
  328         u_int32_t *tl;
  329         int putsize;
  330 
  331         putsize = 1;
  332         m2 = *mb;
  333         left = M_TRAILINGSPACE(m2);
  334         if (left > 0) {
  335                 tl = ((u_int32_t *)(*bpos));
  336                 *tl++ = txdr_unsigned(siz);
  337                 putsize = 0;
  338                 left -= NFSX_UNSIGNED;
  339                 m2->m_len += NFSX_UNSIGNED;
  340                 if (left > 0) {
  341                         bcopy(cp, (caddr_t) tl, left);
  342                         siz -= left;
  343                         cp += left;
  344                         m2->m_len += left;
  345                         left = 0;
  346                 }
  347         }
  348         /* Loop around adding mbufs */
  349         while (siz > 0) {
  350                 MGET(m1, M_TRYWAIT, MT_DATA);
  351                 if (siz > MLEN)
  352                         MCLGET(m1, M_TRYWAIT);
  353                 m1->m_len = NFSMSIZ(m1);
  354                 m2->m_next = m1;
  355                 m2 = m1;
  356                 tl = mtod(m1, u_int32_t *);
  357                 tlen = 0;
  358                 if (putsize) {
  359                         *tl++ = txdr_unsigned(siz);
  360                         m1->m_len -= NFSX_UNSIGNED;
  361                         tlen = NFSX_UNSIGNED;
  362                         putsize = 0;
  363                 }
  364                 if (siz < m1->m_len) {
  365                         len = nfsm_rndup(siz);
  366                         xfer = siz;
  367                         if (xfer < len)
  368                                 *(tl+(xfer>>2)) = 0;
  369                 } else {
  370                         xfer = len = m1->m_len;
  371                 }
  372                 bcopy(cp, (caddr_t) tl, xfer);
  373                 m1->m_len = len+tlen;
  374                 siz -= xfer;
  375                 cp += xfer;
  376         }
  377         *mb = m1;
  378         *bpos = mtod(m1, caddr_t)+m1->m_len;
  379         return (0);
  380 }
  381 
  382 /*
  383  * Called once to initialize data structures...
  384  */
  385 int
  386 nfs_init(struct vfsconf *vfsp)
  387 {
  388         int i;
  389 
  390         nfsmount_zone = uma_zcreate("NFSMOUNT", sizeof(struct nfsmount),
  391             NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
  392         rpc_vers = txdr_unsigned(RPC_VER2);
  393         rpc_call = txdr_unsigned(RPC_CALL);
  394         rpc_reply = txdr_unsigned(RPC_REPLY);
  395         rpc_msgdenied = txdr_unsigned(RPC_MSGDENIED);
  396         rpc_msgaccepted = txdr_unsigned(RPC_MSGACCEPTED);
  397         rpc_mismatch = txdr_unsigned(RPC_MISMATCH);
  398         rpc_autherr = txdr_unsigned(RPC_AUTHERR);
  399         rpc_auth_unix = txdr_unsigned(RPCAUTH_UNIX);
  400         nfs_true = txdr_unsigned(TRUE);
  401         nfs_false = txdr_unsigned(FALSE);
  402         nfs_xdrneg1 = txdr_unsigned(-1);
  403         nfs_ticks = (hz * NFS_TICKINTVL + 500) / 1000;
  404         if (nfs_ticks < 1)
  405                 nfs_ticks = 1;
  406         /* Ensure async daemons disabled */
  407         for (i = 0; i < NFS_MAXASYNCDAEMON; i++) {
  408                 nfs_iodwant[i] = NULL;
  409                 nfs_iodmount[i] = NULL;
  410         }
  411         nfs_nhinit();                   /* Init the nfsnode table */
  412 
  413         /*
  414          * Initialize reply list and start timer
  415          */
  416         TAILQ_INIT(&nfs_reqq);
  417         callout_init(&nfs_callout, 0);
  418         mtx_init(&nfs_reqq_mtx, "NFS reqq lock", NULL, MTX_DEF);
  419         mtx_init(&nfs_reply_mtx, "Synch NFS reply posting", NULL, MTX_DEF);
  420 
  421         nfs_pbuf_freecnt = nswbuf / 2 + 1;
  422 
  423         return (0);
  424 }
  425 
  426 int
  427 nfs_uninit(struct vfsconf *vfsp)
  428 {
  429         int i;
  430 
  431         callout_stop(&nfs_callout);
  432 
  433         KASSERT(TAILQ_EMPTY(&nfs_reqq),
  434             ("nfs_uninit: request queue not empty"));
  435 
  436         /*
  437          * Tell all nfsiod processes to exit. Clear nfs_iodmax, and wakeup
  438          * any sleeping nfsiods so they check nfs_iodmax and exit.
  439          */
  440         nfs_iodmax = 0;
  441         for (i = 0; i < nfs_numasync; i++)
  442                 if (nfs_iodwant[i])
  443                         wakeup(&nfs_iodwant[i]);
  444         /* The last nfsiod to exit will wake us up when nfs_numasync hits 0 */
  445         while (nfs_numasync)
  446                 tsleep(&nfs_numasync, PWAIT, "ioddie", 0);
  447 
  448         nfs_nhuninit();
  449         uma_zdestroy(nfsmount_zone);
  450         return (0);
  451 }
  452 
  453 /*
  454  * Attribute cache routines.
  455  * nfs_loadattrcache() - loads or updates the cache contents from attributes
  456  *      that are on the mbuf list
  457  * nfs_getattrcache() - returns valid attributes if found in cache, returns
  458  *      error otherwise
  459  */
  460 
  461 /*
  462  * Load the attribute cache (that lives in the nfsnode entry) with
  463  * the values on the mbuf list and
  464  * Iff vap not NULL
  465  *    copy the attributes to *vaper
  466  */
  467 int
  468 nfs_loadattrcache(struct vnode **vpp, struct mbuf **mdp, caddr_t *dposp,
  469     struct vattr *vaper, int dontshrink)
  470 {
  471         struct vnode *vp = *vpp;
  472         struct vattr *vap;
  473         struct nfs_fattr *fp;
  474         struct nfsnode *np;
  475         int32_t t1;
  476         caddr_t cp2;
  477         int rdev;
  478         struct mbuf *md;
  479         enum vtype vtyp;
  480         u_short vmode;
  481         struct timespec mtime, mtime_save;
  482         int v3 = NFS_ISV3(vp);
  483 
  484         md = *mdp;
  485         t1 = (mtod(md, caddr_t) + md->m_len) - *dposp;
  486         cp2 = nfsm_disct(mdp, dposp, NFSX_FATTR(v3), t1, M_TRYWAIT);
  487         if (cp2 == NULL)
  488                 return EBADRPC;
  489         fp = (struct nfs_fattr *)cp2;
  490         if (v3) {
  491                 vtyp = nfsv3tov_type(fp->fa_type);
  492                 vmode = fxdr_unsigned(u_short, fp->fa_mode);
  493                 rdev = makedev(fxdr_unsigned(int, fp->fa3_rdev.specdata1),
  494                         fxdr_unsigned(int, fp->fa3_rdev.specdata2));
  495                 fxdr_nfsv3time(&fp->fa3_mtime, &mtime);
  496         } else {
  497                 vtyp = nfsv2tov_type(fp->fa_type);
  498                 vmode = fxdr_unsigned(u_short, fp->fa_mode);
  499                 /*
  500                  * XXX
  501                  *
  502                  * The duplicate information returned in fa_type and fa_mode
  503                  * is an ambiguity in the NFS version 2 protocol.
  504                  *
  505                  * VREG should be taken literally as a regular file.  If a
  506                  * server intents to return some type information differently
  507                  * in the upper bits of the mode field (e.g. for sockets, or
  508                  * FIFOs), NFSv2 mandates fa_type to be VNON.  Anyway, we
  509                  * leave the examination of the mode bits even in the VREG
  510                  * case to avoid breakage for bogus servers, but we make sure
  511                  * that there are actually type bits set in the upper part of
  512                  * fa_mode (and failing that, trust the va_type field).
  513                  *
  514                  * NFSv3 cleared the issue, and requires fa_mode to not
  515                  * contain any type information (while also introduing sockets
  516                  * and FIFOs for fa_type).
  517                  */
  518                 if (vtyp == VNON || (vtyp == VREG && (vmode & S_IFMT) != 0))
  519                         vtyp = IFTOVT(vmode);
  520                 rdev = fxdr_unsigned(int32_t, fp->fa2_rdev);
  521                 fxdr_nfsv2time(&fp->fa2_mtime, &mtime);
  522 
  523                 /*
  524                  * Really ugly NFSv2 kludge.
  525                  */
  526                 if (vtyp == VCHR && rdev == 0xffffffff)
  527                         vtyp = VFIFO;
  528         }
  529 
  530         /*
  531          * If v_type == VNON it is a new node, so fill in the v_type,
  532          * n_mtime fields. Check to see if it represents a special
  533          * device, and if so, check for a possible alias. Once the
  534          * correct vnode has been obtained, fill in the rest of the
  535          * information.
  536          */
  537         np = VTONFS(vp);
  538         if (vp->v_type != vtyp) {
  539                 vp->v_type = vtyp;
  540                 if (vp->v_type == VFIFO)
  541                         vp->v_op = &nfs_fifoops;
  542                 np->n_mtime = mtime;
  543         }
  544         vap = &np->n_vattr;
  545         vap->va_type = vtyp;
  546         vap->va_mode = (vmode & 07777);
  547         vap->va_rdev = rdev;
  548         mtime_save = vap->va_mtime;
  549         vap->va_mtime = mtime;
  550         vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
  551         if (v3) {
  552                 vap->va_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
  553                 vap->va_uid = fxdr_unsigned(uid_t, fp->fa_uid);
  554                 vap->va_gid = fxdr_unsigned(gid_t, fp->fa_gid);
  555                 vap->va_size = fxdr_hyper(&fp->fa3_size);
  556                 vap->va_blocksize = NFS_FABLKSIZE;
  557                 vap->va_bytes = fxdr_hyper(&fp->fa3_used);
  558                 vap->va_fileid = fxdr_unsigned(int32_t,
  559                     fp->fa3_fileid.nfsuquad[1]);
  560                 fxdr_nfsv3time(&fp->fa3_atime, &vap->va_atime);
  561                 fxdr_nfsv3time(&fp->fa3_ctime, &vap->va_ctime);
  562                 vap->va_flags = 0;
  563                 vap->va_filerev = 0;
  564         } else {
  565                 vap->va_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
  566                 vap->va_uid = fxdr_unsigned(uid_t, fp->fa_uid);
  567                 vap->va_gid = fxdr_unsigned(gid_t, fp->fa_gid);
  568                 vap->va_size = fxdr_unsigned(u_int32_t, fp->fa2_size);
  569                 vap->va_blocksize = fxdr_unsigned(int32_t, fp->fa2_blocksize);
  570                 vap->va_bytes = (u_quad_t)fxdr_unsigned(int32_t, fp->fa2_blocks)
  571                     * NFS_FABLKSIZE;
  572                 vap->va_fileid = fxdr_unsigned(int32_t, fp->fa2_fileid);
  573                 fxdr_nfsv2time(&fp->fa2_atime, &vap->va_atime);
  574                 vap->va_flags = 0;
  575                 vap->va_ctime.tv_sec = fxdr_unsigned(u_int32_t,
  576                     fp->fa2_ctime.nfsv2_sec);
  577                 vap->va_ctime.tv_nsec = 0;
  578                 vap->va_gen = fxdr_unsigned(u_int32_t, fp->fa2_ctime.nfsv2_usec);
  579                 vap->va_filerev = 0;
  580         }
  581         np->n_attrstamp = time_second;
  582         if (vap->va_size != np->n_size) {
  583                 if (vap->va_type == VREG) {
  584                         if (dontshrink && vap->va_size < np->n_size) {
  585                                 /*
  586                                  * We've been told not to shrink the file;
  587                                  * zero np->n_attrstamp to indicate that
  588                                  * the attributes are stale.
  589                                  */
  590                                 vap->va_size = np->n_size;
  591                                 np->n_attrstamp = 0;
  592                         } else if (np->n_flag & NMODIFIED) {
  593                                 /*
  594                                  * We've modified the file: Use the larger
  595                                  * of our size, and the server's size.
  596                                  */
  597                                 if (vap->va_size < np->n_size) {
  598                                         vap->va_size = np->n_size;
  599                                 } else {
  600                                         np->n_size = vap->va_size;
  601                                         np->n_flag |= NSIZECHANGED;
  602                                 }
  603                         } else {
  604                                 np->n_size = vap->va_size;
  605                                 np->n_flag |= NSIZECHANGED;
  606                         }
  607                         vnode_pager_setsize(vp, np->n_size);
  608                 } else {
  609                         np->n_size = vap->va_size;
  610                 }
  611         }
  612         /*
  613          * The following checks are added to prevent a race between (say)
  614          * a READDIR+ and a WRITE. 
  615          * READDIR+, WRITE requests sent out.
  616          * READDIR+ resp, WRITE resp received on client.
  617          * However, the WRITE resp was handled before the READDIR+ resp
  618          * causing the post op attrs from the write to be loaded first
  619          * and the attrs from the READDIR+ to be loaded later. If this 
  620          * happens, we have stale attrs loaded into the attrcache.
  621          * We detect this by for the mtime moving back. We invalidate the 
  622          * attrcache when this happens.
  623          */
  624         if (timespeccmp(&mtime_save, &vap->va_mtime, >))
  625                 /* Size changed or mtime went backwards */
  626                 np->n_attrstamp = 0;
  627         if (vaper != NULL) {
  628                 bcopy((caddr_t)vap, (caddr_t)vaper, sizeof(*vap));
  629                 if (np->n_flag & NCHG) {
  630                         if (np->n_flag & NACC)
  631                                 vaper->va_atime = np->n_atim;
  632                         if (np->n_flag & NUPD)
  633                                 vaper->va_mtime = np->n_mtim;
  634                 }
  635         }
  636         return (0);
  637 }
  638 
  639 #ifdef NFS_ACDEBUG
  640 #include <sys/sysctl.h>
  641 SYSCTL_DECL(_vfs_nfs);
  642 static int nfs_acdebug;
  643 SYSCTL_INT(_vfs_nfs, OID_AUTO, acdebug, CTLFLAG_RW, &nfs_acdebug, 0, "");
  644 #endif
  645 
  646 /*
  647  * Check the time stamp
  648  * If the cache is valid, copy contents to *vap and return 0
  649  * otherwise return an error
  650  */
  651 int
  652 nfs_getattrcache(struct vnode *vp, struct vattr *vaper)
  653 {
  654         struct nfsnode *np;
  655         struct vattr *vap;
  656         struct nfsmount *nmp;
  657         int timeo;
  658 
  659         np = VTONFS(vp);
  660         vap = &np->n_vattr;
  661         nmp = VFSTONFS(vp->v_mount);
  662         /* XXX n_mtime doesn't seem to be updated on a miss-and-reload */
  663         timeo = (time_second - np->n_mtime.tv_sec) / 10;
  664 
  665 #ifdef NFS_ACDEBUG
  666         if (nfs_acdebug>1)
  667                 printf("nfs_getattrcache: initial timeo = %d\n", timeo);
  668 #endif
  669 
  670         if (vap->va_type == VDIR) {
  671                 if ((np->n_flag & NMODIFIED) || timeo < nmp->nm_acdirmin)
  672                         timeo = nmp->nm_acdirmin;
  673                 else if (timeo > nmp->nm_acdirmax)
  674                         timeo = nmp->nm_acdirmax;
  675         } else {
  676                 if ((np->n_flag & NMODIFIED) || timeo < nmp->nm_acregmin)
  677                         timeo = nmp->nm_acregmin;
  678                 else if (timeo > nmp->nm_acregmax)
  679                         timeo = nmp->nm_acregmax;
  680         }
  681 
  682 #ifdef NFS_ACDEBUG
  683         if (nfs_acdebug > 2)
  684                 printf("acregmin %d; acregmax %d; acdirmin %d; acdirmax %d\n",
  685                         nmp->nm_acregmin, nmp->nm_acregmax,
  686                         nmp->nm_acdirmin, nmp->nm_acdirmax);
  687 
  688         if (nfs_acdebug)
  689                 printf("nfs_getattrcache: age = %d; final timeo = %d\n",
  690                         (time_second - np->n_attrstamp), timeo);
  691 #endif
  692 
  693         if ((time_second - np->n_attrstamp) >= timeo) {
  694                 nfsstats.attrcache_misses++;
  695                 return (ENOENT);
  696         }
  697         nfsstats.attrcache_hits++;
  698         if (vap->va_size != np->n_size) {
  699                 if (vap->va_type == VREG) {
  700                         if (np->n_flag & NMODIFIED) {
  701                                 if (vap->va_size < np->n_size)
  702                                         vap->va_size = np->n_size;
  703                                 else
  704                                         np->n_size = vap->va_size;
  705                         } else {
  706                                 np->n_size = vap->va_size;
  707                         }
  708                         vnode_pager_setsize(vp, np->n_size);
  709                 } else {
  710                         np->n_size = vap->va_size;
  711                 }
  712         }
  713         bcopy((caddr_t)vap, (caddr_t)vaper, sizeof(struct vattr));
  714         if (np->n_flag & NCHG) {
  715                 if (np->n_flag & NACC)
  716                         vaper->va_atime = np->n_atim;
  717                 if (np->n_flag & NUPD)
  718                         vaper->va_mtime = np->n_mtim;
  719         }
  720         return (0);
  721 }
  722 
  723 static nfsuint64 nfs_nullcookie = { { 0, 0 } };
  724 /*
  725  * This function finds the directory cookie that corresponds to the
  726  * logical byte offset given.
  727  */
  728 nfsuint64 *
  729 nfs_getcookie(struct nfsnode *np, off_t off, int add)
  730 {
  731         struct nfsdmap *dp, *dp2;
  732         int pos;
  733 
  734         pos = (uoff_t)off / NFS_DIRBLKSIZ;
  735         if (pos == 0 || off < 0) {
  736 #ifdef DIAGNOSTIC
  737                 if (add)
  738                         panic("nfs getcookie add at <= 0");
  739 #endif
  740                 return (&nfs_nullcookie);
  741         }
  742         pos--;
  743         dp = LIST_FIRST(&np->n_cookies);
  744         if (!dp) {
  745                 if (add) {
  746                         MALLOC(dp, struct nfsdmap *, sizeof (struct nfsdmap),
  747                                 M_NFSDIROFF, M_WAITOK);
  748                         dp->ndm_eocookie = 0;
  749                         LIST_INSERT_HEAD(&np->n_cookies, dp, ndm_list);
  750                 } else
  751                         return (NULL);
  752         }
  753         while (pos >= NFSNUMCOOKIES) {
  754                 pos -= NFSNUMCOOKIES;
  755                 if (LIST_NEXT(dp, ndm_list)) {
  756                         if (!add && dp->ndm_eocookie < NFSNUMCOOKIES &&
  757                                 pos >= dp->ndm_eocookie)
  758                                 return (NULL);
  759                         dp = LIST_NEXT(dp, ndm_list);
  760                 } else if (add) {
  761                         MALLOC(dp2, struct nfsdmap *, sizeof (struct nfsdmap),
  762                                 M_NFSDIROFF, M_WAITOK);
  763                         dp2->ndm_eocookie = 0;
  764                         LIST_INSERT_AFTER(dp, dp2, ndm_list);
  765                         dp = dp2;
  766                 } else
  767                         return (NULL);
  768         }
  769         if (pos >= dp->ndm_eocookie) {
  770                 if (add)
  771                         dp->ndm_eocookie = pos + 1;
  772                 else
  773                         return (NULL);
  774         }
  775         return (&dp->ndm_cookies[pos]);
  776 }
  777 
  778 /*
  779  * Invalidate cached directory information, except for the actual directory
  780  * blocks (which are invalidated separately).
  781  * Done mainly to avoid the use of stale offset cookies.
  782  */
  783 void
  784 nfs_invaldir(struct vnode *vp)
  785 {
  786         struct nfsnode *np = VTONFS(vp);
  787 
  788 #ifdef DIAGNOSTIC
  789         if (vp->v_type != VDIR)
  790                 panic("nfs: invaldir not dir");
  791 #endif
  792         np->n_direofoffset = 0;
  793         np->n_cookieverf.nfsuquad[0] = 0;
  794         np->n_cookieverf.nfsuquad[1] = 0;
  795         if (LIST_FIRST(&np->n_cookies))
  796                 LIST_FIRST(&np->n_cookies)->ndm_eocookie = 0;
  797 }
  798 
  799 /*
  800  * The write verifier has changed (probably due to a server reboot), so all
  801  * B_NEEDCOMMIT blocks will have to be written again. Since they are on the
  802  * dirty block list as B_DELWRI, all this takes is clearing the B_NEEDCOMMIT
  803  * and B_CLUSTEROK flags.  Once done the new write verifier can be set for the
  804  * mount point.
  805  *
  806  * B_CLUSTEROK must be cleared along with B_NEEDCOMMIT because stage 1 data
  807  * writes are not clusterable.
  808  */
  809 void
  810 nfs_clearcommit(struct mount *mp)
  811 {
  812         struct vnode *vp, *nvp;
  813         struct buf *bp, *nbp;
  814         int s;
  815 
  816         GIANT_REQUIRED;
  817 
  818         s = splbio();
  819         MNT_ILOCK(mp);
  820         MNT_VNODE_FOREACH(vp, mp, nvp) {
  821                 VI_LOCK(vp);
  822                 if (vp->v_iflag & VI_DOOMED) {
  823                         VI_UNLOCK(vp);
  824                         continue;
  825                 }
  826                 MNT_IUNLOCK(mp);
  827                 TAILQ_FOREACH_SAFE(bp, &vp->v_bufobj.bo_dirty.bv_hd, b_bobufs, nbp) {
  828                         if (BUF_REFCNT(bp) == 0 &&
  829                             (bp->b_flags & (B_DELWRI | B_NEEDCOMMIT))
  830                                 == (B_DELWRI | B_NEEDCOMMIT))
  831                                 bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
  832                 }
  833                 VI_UNLOCK(vp);
  834                 MNT_ILOCK(mp);
  835         }
  836         MNT_IUNLOCK(mp);
  837         splx(s);
  838 }
  839 
  840 /*
  841  * Helper functions for former macros.  Some of these should be
  842  * moved to their callers.
  843  */
  844 
  845 int
  846 nfsm_mtofh_xx(struct vnode *d, struct vnode **v, int v3, int *f,
  847     struct mbuf **md, caddr_t *dpos)
  848 {
  849         struct nfsnode *ttnp;
  850         struct vnode *ttvp;
  851         nfsfh_t *ttfhp;
  852         u_int32_t *tl;
  853         int ttfhsize;
  854         int t1;
  855 
  856         if (v3) {
  857                 tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
  858                 if (tl == NULL)
  859                         return EBADRPC;
  860                 *f = fxdr_unsigned(int, *tl);
  861         } else
  862                 *f = 1;
  863         if (*f) {
  864                 t1 = nfsm_getfh_xx(&ttfhp, &ttfhsize, (v3), md, dpos);
  865                 if (t1 != 0)
  866                         return t1;
  867                 t1 = nfs_nget(d->v_mount, ttfhp, ttfhsize, &ttnp, LK_EXCLUSIVE);
  868                 if (t1 != 0)
  869                         return t1;
  870                 *v = NFSTOV(ttnp);
  871         }
  872         if (v3) {
  873                 tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
  874                 if (tl == NULL)
  875                         return EBADRPC;
  876                 if (*f)
  877                         *f = fxdr_unsigned(int, *tl);
  878                 else if (fxdr_unsigned(int, *tl))
  879                         nfsm_adv_xx(NFSX_V3FATTR, md, dpos);
  880         }
  881         if (*f) {
  882                 ttvp = *v;
  883                 t1 = nfs_loadattrcache(&ttvp, md, dpos, NULL, 0);
  884                 if (t1)
  885                         return t1;
  886                 *v = ttvp;
  887         }
  888         return 0;
  889 }
  890 
  891 int
  892 nfsm_getfh_xx(nfsfh_t **f, int *s, int v3, struct mbuf **md, caddr_t *dpos)
  893 {
  894         u_int32_t *tl;
  895 
  896         if (v3) {
  897                 tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
  898                 if (tl == NULL)
  899                         return EBADRPC;
  900                 *s = fxdr_unsigned(int, *tl);
  901                 if (*s <= 0 || *s > NFSX_V3FHMAX)
  902                         return EBADRPC;
  903         } else
  904                 *s = NFSX_V2FH;
  905         *f = nfsm_dissect_xx(nfsm_rndup(*s), md, dpos);
  906         if (*f == NULL)
  907                 return EBADRPC;
  908         else
  909                 return 0;
  910 }
  911 
  912 
  913 int
  914 nfsm_loadattr_xx(struct vnode **v, struct vattr *va, struct mbuf **md,
  915     caddr_t *dpos)
  916 {
  917         int t1;
  918 
  919         struct vnode *ttvp = *v;
  920         t1 = nfs_loadattrcache(&ttvp, md, dpos, va, 0);
  921         if (t1 != 0)
  922                 return t1;
  923         *v = ttvp;
  924         return 0;
  925 }
  926 
  927 int
  928 nfsm_postop_attr_xx(struct vnode **v, int *f, struct mbuf **md,
  929     caddr_t *dpos)
  930 {
  931         u_int32_t *tl;
  932         int t1;
  933 
  934         struct vnode *ttvp = *v;
  935         tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
  936         if (tl == NULL)
  937                 return EBADRPC;
  938         *f = fxdr_unsigned(int, *tl);
  939         if (*f != 0) {
  940                 t1 = nfs_loadattrcache(&ttvp, md, dpos, NULL, 1);
  941                 if (t1 != 0) {
  942                         *f = 0;
  943                         return t1;
  944                 }
  945                 *v = ttvp;
  946         }
  947         return 0;
  948 }
  949 
  950 int
  951 nfsm_wcc_data_xx(struct vnode **v, int *f, struct mbuf **md, caddr_t *dpos)
  952 {
  953         u_int32_t *tl;
  954         int ttattrf, ttretf = 0;
  955         int t1;
  956 
  957         tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
  958         if (tl == NULL)
  959                 return EBADRPC;
  960         if (*tl == nfs_true) {
  961                 tl = nfsm_dissect_xx(6 * NFSX_UNSIGNED, md, dpos);
  962                 if (tl == NULL)
  963                         return EBADRPC;
  964                 if (*f)
  965                         ttretf = (VTONFS(*v)->n_mtime.tv_sec == fxdr_unsigned(u_int32_t, *(tl + 2)) && 
  966                                   VTONFS(*v)->n_mtime.tv_nsec == fxdr_unsigned(u_int32_t, *(tl + 3))); 
  967         }
  968         t1 = nfsm_postop_attr_xx(v, &ttattrf, md, dpos);
  969         if (t1)
  970                 return t1;
  971         if (*f)
  972                 *f = ttretf;
  973         else
  974                 *f = ttattrf;
  975         return 0;
  976 }
  977 
  978 int
  979 nfsm_strtom_xx(const char *a, int s, int m, struct mbuf **mb, caddr_t *bpos)
  980 {
  981         u_int32_t *tl;
  982         int t1;
  983 
  984         if (s > m)
  985                 return ENAMETOOLONG;
  986         t1 = nfsm_rndup(s) + NFSX_UNSIGNED;
  987         if (t1 <= M_TRAILINGSPACE(*mb)) {
  988                 tl = nfsm_build_xx(t1, mb, bpos);
  989                 *tl++ = txdr_unsigned(s);
  990                 *(tl + ((t1 >> 2) - 2)) = 0;
  991                 bcopy(a, tl, s);
  992         } else {
  993                 t1 = nfsm_strtmbuf(mb, bpos, a, s);
  994                 if (t1 != 0)
  995                         return t1;
  996         }
  997         return 0;
  998 }
  999 
 1000 int
 1001 nfsm_fhtom_xx(struct vnode *v, int v3, struct mbuf **mb, caddr_t *bpos)
 1002 {
 1003         u_int32_t *tl;
 1004         int t1;
 1005         caddr_t cp;
 1006 
 1007         if (v3) {
 1008                 t1 = nfsm_rndup(VTONFS(v)->n_fhsize) + NFSX_UNSIGNED;
 1009                 if (t1 < M_TRAILINGSPACE(*mb)) {
 1010                         tl = nfsm_build_xx(t1, mb, bpos);
 1011                         *tl++ = txdr_unsigned(VTONFS(v)->n_fhsize);
 1012                         *(tl + ((t1 >> 2) - 2)) = 0;
 1013                         bcopy(VTONFS(v)->n_fhp, tl, VTONFS(v)->n_fhsize);
 1014                 } else {
 1015                         t1 = nfsm_strtmbuf(mb, bpos,
 1016                             (const char *)VTONFS(v)->n_fhp,
 1017                             VTONFS(v)->n_fhsize);
 1018                         if (t1 != 0)
 1019                                 return t1;
 1020                 }
 1021         } else {
 1022                 cp = nfsm_build_xx(NFSX_V2FH, mb, bpos);
 1023                 bcopy(VTONFS(v)->n_fhp, cp, NFSX_V2FH);
 1024         }
 1025         return 0;
 1026 }
 1027 
 1028 void
 1029 nfsm_v3attrbuild_xx(struct vattr *va, int full, struct mbuf **mb,
 1030     caddr_t *bpos)
 1031 {
 1032         u_int32_t *tl;
 1033 
 1034         if (va->va_mode != (mode_t)VNOVAL) {
 1035                 tl = nfsm_build_xx(2 * NFSX_UNSIGNED, mb, bpos);
 1036                 *tl++ = nfs_true;
 1037                 *tl = txdr_unsigned(va->va_mode);
 1038         } else {
 1039                 tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
 1040                 *tl = nfs_false;
 1041         }
 1042         if (full && va->va_uid != (uid_t)VNOVAL) {
 1043                 tl = nfsm_build_xx(2 * NFSX_UNSIGNED, mb, bpos);
 1044                 *tl++ = nfs_true;
 1045                 *tl = txdr_unsigned(va->va_uid);
 1046         } else {
 1047                 tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
 1048                 *tl = nfs_false;
 1049         }
 1050         if (full && va->va_gid != (gid_t)VNOVAL) {
 1051                 tl = nfsm_build_xx(2 * NFSX_UNSIGNED, mb, bpos);
 1052                 *tl++ = nfs_true;
 1053                 *tl = txdr_unsigned(va->va_gid);
 1054         } else {
 1055                 tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
 1056                 *tl = nfs_false;
 1057         }
 1058         if (full && va->va_size != VNOVAL) {
 1059                 tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
 1060                 *tl++ = nfs_true;
 1061                 txdr_hyper(va->va_size, tl);
 1062         } else {
 1063                 tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
 1064                 *tl = nfs_false;
 1065         }
 1066         if (va->va_atime.tv_sec != VNOVAL) {
 1067                 if (va->va_atime.tv_sec != time_second) {
 1068                         tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
 1069                         *tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
 1070                         txdr_nfsv3time(&va->va_atime, tl);
 1071                 } else {
 1072                         tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
 1073                         *tl = txdr_unsigned(NFSV3SATTRTIME_TOSERVER);
 1074                 }
 1075         } else {
 1076                 tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
 1077                 *tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
 1078         }
 1079         if (va->va_mtime.tv_sec != VNOVAL) {
 1080                 if (va->va_mtime.tv_sec != time_second) {
 1081                         tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
 1082                         *tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
 1083                         txdr_nfsv3time(&va->va_mtime, tl);
 1084                 } else {
 1085                         tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
 1086                         *tl = txdr_unsigned(NFSV3SATTRTIME_TOSERVER);
 1087                 }
 1088         } else {
 1089                 tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
 1090                 *tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
 1091         }
 1092 }

Cache object: d042b798d0214cb1b06b838490989b61


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