NFS update + make some examples configurable as NSH built-ins

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@4501 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 927 insertions, 0 deletions

diff --git a/nuttx/fs/nfs/nfs_vfsops.c b/nuttx/fs/nfs/nfs_vfsops.c
new file mode 100644
index 000000000..407963abd
--- /dev/null
+++ b/nuttx/fs/nfs/nfs_vfsops.c
@@ -0,0 +1,927 @@
+/****************************************************************************
+ * fs/nfs/nfs_vfsops.c
+ *
+ *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012 Jose Pablo Rojas Vargas. All rights reserved.
+ *   Author: Jose Pablo Rojas Vargas <jrojas@nx-engineering.com>
+ *
+ * Leveraged from OpenBSD:
+ *
+ *   Copyright (c) 1989, 1993, 1995
+ *   The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Rick Macklem at The University of Guelph.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <sys/param.h>
+#include <sys/conf.h>
+#include <sys/ioctl.h>
+#include <sys/signal.h>
+#include <sys/proc.h>
+#include <sys/namei.h>
+#include <sys/vnode.h>
+#include <sys/kernel.h>
+#include <sys/mount.h>
+#include <sys/buf.h>
+#include <sys/mbuf.h>
+#include <sys/dirent.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+#include <sys/systm.h>
+#include <sys/sysctl.h>
+
+#include <sys/statfs>
+#include <sys/queue.h>
+
+#include <net/if.h>
+#include <net/route.h>
+#include <netinet/in.h>
+
+#include <nfs/rpcv2.h>
+#include <nfs/nfsproto.h>
+#include <nfs/nfsnode.h>
+#include <nfs/nfs.h>
+#include <nfs/nfsmount.h>
+#include <nfs/xdr_subs.h>
+#include <nfs/nfsm_subs.h>
+#include <nfs/nfsdiskless.h>
+#include <nfs/nfs_var.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Definitions
+ ****************************************************************************/
+
+/* nfs vfs operations. */
+
+const struct vfsops nfs_vfsops =
+{
+  nfs_mount,
+  nfs_start,
+  nfs_unmount,
+  nfs_root,
+  nfs_quotactl,
+  nfs_statfs,
+  nfs_sync,
+  nfs_vget,
+  nfs_fhtovp,
+  nfs_vptofh,
+  nfs_vfs_init,
+  nfs_sysctl,
+  nfs_checkexp
+};
+
+/****************************************************************************
+ * External Public Data  (this belong in a header file)
+ ****************************************************************************/
+
+extern struct nfsstats nfsstats;
+extern int nfs_ticks;
+extern uint32_t nfs_procids[NFS_NPROCS];
+
+/****************************************************************************
+ * Public Function Prototypes (this belong in a header file)
+ ****************************************************************************/
+
+int nfs_sysctl(int *, u_int, void *, size_t *, void *, size_t, struct proc *);
+int nfs_checkexp(struct mount *, struct mbuf *, int *, struct ucred **);
+struct mount *nfs_mount_diskless(struct nfs_dlmount *, char *, int);
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Publikc Functions
+ ****************************************************************************/
+
+/* nfs statfs call */
+
+int nfs_statfs(struct file *filep, struct statfs *sbp)
+{
+  struct nfs_statfs *sfp = NULL;
+  struct nfsmount *nmp = VFSTONFS(filep->f_inode);
+  int error = 0;
+  struct nfsnode *np = VTONFS(filep->f_priv);
+  uint64_t tquad;
+
+  error = nfs_nget(mp, (nfsfh_t *) nmp->nm_fh, nmp->nm_fhsize, &np);
+  if (error)
+    return (error);
+
+  if ((nmp->nm_flag & NFSMNT_GOTFSINFO) == 0)
+    (void)nfs_fsinfo(nmp);
+  nfsstats.rpccnt[NFSPROC_FSSTAT]++;
+
+  error = nfs_request(nmp, NFSPROC_FSSTAT);
+  if (error)
+    goto nfsmout;
+
+  sbp->f_iosize = min(nmp->nm_rsize, nmp->nm_wsize);
+  if (info.nmi_v3)
+    {
+      sbp->f_bsize = NFS_FABLKSIZE;
+      tquad = fxdr_hyper(&sfp->sf_tbytes);
+      sbp->f_blocks = tquad / (u_quad_t) NFS_FABLKSIZE;
+      tquad = fxdr_hyper(&sfp->sf_fbytes);
+      sbp->f_bfree = tquad / (u_quad_t) NFS_FABLKSIZE;
+      tquad = fxdr_hyper(&sfp->sf_abytes);
+      sbp->f_bavail = (quad_t) tquad / (quad_t) NFS_FABLKSIZE;
+
+      tquad = fxdr_hyper(&sfp->sf_tfiles);
+      sbp->f_files = tquad;
+      tquad = fxdr_hyper(&sfp->sf_ffiles);
+      sbp->f_ffree = tquad;
+      sbp->f_favail = tquad;
+      sbp->f_namemax = MAXNAMLEN;
+    }
+  else
+    {
+      sbp->f_bsize = fxdr_unsigned(int32_t, sfp->sf_bsize);
+      sbp->f_blocks = fxdr_unsigned(int32_t, sfp->sf_blocks);
+      sbp->f_bfree = fxdr_unsigned(int32_t, sfp->sf_bfree);
+      sbp->f_bavail = fxdr_unsigned(int32_t, sfp->sf_bavail);
+      sbp->f_files = 0;
+      sbp->f_ffree = 0;
+    }
+  copy_statfs_info(sbp, mp);
+nfsmout:
+  return (error);
+}
+
+/* nfs version 3 fsinfo rpc call */
+
+int nfs_fsinfo(struct nfsmount *nmp)
+{
+  struct nfsv3_fsinfo *fsp;
+  struct nfsm_info info;
+  uint32_t pref, max;
+  int error = 0;
+
+  nfsstats.rpccnt[NFSPROC_FSINFO]++;
+
+  error = nfs_request(nmp, NFSPROC_FSINFO);
+  if (error)
+    {
+      goto nfsmout;
+    }
+
+  pref = fxdr_unsigned(uint32_t, fsp->fs_wtpref);
+  if (pref < nmp->nm_wsize)
+    nmp->nm_wsize = (pref + NFS_FABLKSIZE - 1) & ~(NFS_FABLKSIZE - 1);
+  max = fxdr_unsigned(uint32_t, fsp->fs_wtmax);
+  if (max < nmp->nm_wsize)
+    {
+      nmp->nm_wsize = max & ~(NFS_FABLKSIZE - 1);
+      if (nmp->nm_wsize == 0)
+        nmp->nm_wsize = max;
+    }
+  pref = fxdr_unsigned(uint32_t, fsp->fs_rtpref);
+  if (pref < nmp->nm_rsize)
+    nmp->nm_rsize = (pref + NFS_FABLKSIZE - 1) & ~(NFS_FABLKSIZE - 1);
+  max = fxdr_unsigned(uint32_t, fsp->fs_rtmax);
+  if (max < nmp->nm_rsize)
+    {
+      nmp->nm_rsize = max & ~(NFS_FABLKSIZE - 1);
+      if (nmp->nm_rsize == 0)
+        nmp->nm_rsize = max;
+    }
+  pref = fxdr_unsigned(uint32_t, fsp->fs_dtpref);
+  if (pref < nmp->nm_readdirsize)
+    nmp->nm_readdirsize = (pref + NFS_DIRBLKSIZ - 1) & ~(NFS_DIRBLKSIZ - 1);
+  if (max < nmp->nm_readdirsize)
+    {
+      nmp->nm_readdirsize = max & ~(NFS_DIRBLKSIZ - 1);
+      if (nmp->nm_readdirsize == 0)
+        nmp->nm_readdirsize = max;
+    }
+  nmp->nm_flag |= NFSMNT_GOTFSINFO;
+
+nfsmout:
+  return (error);
+}
+
+/* Mount a remote root fs via. NFS.  It goes like this:
+ * - Call nfs_boot_init() to fill in the nfs_diskless struct
+ *   (using RARP, bootparam RPC, mountd RPC)
+ * - hand craft the swap nfs vnode hanging off a fake mount point
+ *      if swdevt[0].sw_dev == NODEV
+ * - build the rootfs mount point and call mountnfs() to do the rest.
+ */
+
+int nfs_mountroot(void)
+{
+  struct nfs_diskless nd;
+  struct vattr attr;
+  struct mount *mp;
+  struct vnode *vp;
+  struct proc *procp;
+  long n;
+  int error;
+
+  procp = curproc;              /* XXX */
+
+  /* Call nfs_boot_init() to fill in the nfs_diskless struct.
+   * Side effect:  Finds and configures a network interface.
+   */
+
+  bzero((caddr_t) & nd, sizeof(nd));
+  nfs_boot_init(&nd, procp);
+
+  /* Create the root mount point. */
+
+  if (nfs_boot_getfh(&nd.nd_boot, "root", &nd.nd_root, -1))
+    panic("nfs_mountroot: root");
+  mp = nfs_mount_diskless(&nd.nd_root, "/", 0);
+  nfs_root(mp, &rootvp);
+  printf("root on %s\n", nd.nd_root.ndm_host);
+
+  /* Link it into the mount list. */
+
+  CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
+  vfs_unbusy(mp);
+
+  /* Get root attributes (for the time). */
+
+  error = VOP_GETATTR(rootvp, &attr, procp->p_ucred, procp);
+  if (error)
+    panic("nfs_mountroot: getattr for root");
+  n = attr.va_atime.tv_sec;
+#ifdef  DEBUG
+  printf("root time: 0x%lx\n", n);
+#endif
+  inittodr(n);
+
+#ifdef notyet
+  /* Set up swap credentials. */
+
+  proc0.p_ucred->cr_uid = ntohl(nd.swap_ucred.cr_uid);
+  proc0.p_ucred->cr_gid = ntohl(nd.swap_ucred.cr_gid);
+  if ((proc0.p_ucred->cr_ngroups = ntohs(nd.swap_ucred.cr_ngroups)) > NGROUPS)
+    proc0.p_ucred->cr_ngroups = NGROUPS;
+  for (i = 0; i < proc0.p_ucred->cr_ngroups; i++)
+    proc0.p_ucred->cr_groups[i] = ntohl(nd.swap_ucred.cr_groups[i]);
+#endif
+
+  /* "Mount" the swap device.
+   *
+   * On a "dataless" configuration (swap on disk) we will have:
+   *      (swdevt[0].sw_dev != NODEV) identifying the swap device.
+   */
+
+  if (bdevvp(swapdev, &swapdev_vp))
+    panic("nfs_mountroot: can't setup swap vp");
+  if (swdevt[0].sw_dev != NODEV)
+    {
+      printf("swap on device 0x%x\n", swdevt[0].sw_dev);
+      return (0);
+    }
+
+  /* If swapping to an nfs node:  (swdevt[0].sw_dev == NODEV)
+   * Create a fake mount point just for the swap vnode so that the
+   * swap file can be on a different server from the rootfs.
+   *
+   * Wait 5 retries, finally no swap is cool. -mickey
+   */
+
+  error = nfs_boot_getfh(&nd.nd_boot, "swap", &nd.nd_swap, 5);
+  if (!error)
+    {
+      mp = nfs_mount_diskless(&nd.nd_swap, "/swap", 0);
+      nfs_root(mp, &vp);
+      vfs_unbusy(mp);
+
+      /* Since the swap file is not the root dir of a file system,
+       * hack it to a regular file.
+       */
+
+      vp->v_type = VREG;
+      vp->v_flag = 0;
+
+      /* Next line is a hack to make swapmount() work on NFS
+       * swap files.
+       * XXX-smurph
+       */
+
+      swdevt[0].sw_dev = NETDEV;
+      /* end hack */
+      swdevt[0].sw_vp = vp;
+
+      /* Find out how large the swap file is. */
+
+      error = VOP_GETATTR(vp, &attr, procp->p_ucred, procp);
+      if (error)
+        printf("nfs_mountroot: getattr for swap\n");
+      n = (long)(attr.va_size >> DEV_BSHIFT);
+
+      printf("swap on %s\n", nd.nd_swap.ndm_host);
+#ifdef  DEBUG
+      printf("swap size: 0x%lx (blocks)\n", n);
+#endif
+      return (0);
+    }
+
+  printf("WARNING: no swap\n");
+  swdevt[0].sw_dev = NODEV;
+  swdevt[0].sw_vp = NULL;
+
+  return (0);
+}
+
+/* Internal version of mount system call for diskless setup. */
+
+struct mount *nfs_mount_diskless(struct nfs_dlmount *ndmntp, char *mntname,
+                                 int mntflag)
+{
+  struct nfs_args args;
+  struct mount *mp;
+  struct mbuf *m;
+  int error;
+
+  if (vfs_rootmountalloc("nfs", mntname, &mp))
+    panic("nfs_mount_diskless: vfs_rootmountalloc failed");
+  mp->mnt_flag |= mntflag;
+
+  /* Initialize mount args. */
+
+  bzero((caddr_t) & args, sizeof(args));
+  args.addr = (struct sockaddr *)&ndmntp->ndm_saddr;
+  args.addrlen = args.addr->sa_len;
+  args.sotype = SOCK_DGRAM;
+  args.fh = ndmntp->ndm_fh;
+  args.fhsize = NFSX_V2FH;
+  args.hostname = ndmntp->ndm_host;
+
+#ifdef  NFS_BOOT_OPTIONS
+  args.flags |= NFS_BOOT_OPTIONS;
+#endif
+#ifdef  NFS_BOOT_RWSIZE
+  /* Reduce rsize,wsize for interfaces that consistently
+   * drop fragments of long UDP messages.  (i.e. wd8003).
+   * You can always change these later via remount.
+   */
+
+  args.flags |= NFSMNT_WSIZE | NFSMNT_RSIZE;
+  args.wsize = NFS_BOOT_RWSIZE;
+  args.rsize = NFS_BOOT_RWSIZE;
+#endif
+
+  /* Get mbuf for server sockaddr. */
+
+  m = m_get(M_WAIT, MT_SONAME);
+  bcopy((caddr_t) args.addr, mtod(m, caddr_t), (m->m_len = args.addr->sa_len));
+
+  error = mountnfs(&args, mp, m, mntname, args.hostname);
+  if (error)
+    panic("nfs_mountroot: mount %s failed: %d", mntname, error);
+
+  return (mp);
+}
+
+void
+nfs_decode_args(struct nfsmount *nmp, struct nfs_args *argp,
+                struct nfs_args *nargp)
+{
+  int s;
+  int adjsock = 0;
+  int maxio;
+
+  s = splsoftnet();
+
+#if 0
+  /* Re-bind if rsrvd port requested and wasn't on one */
+
+  adjsock = !(nmp->nm_flag & NFSMNT_RESVPORT)
+    && (argp->flags & NFSMNT_RESVPORT);
+#endif
+  /* Also re-bind if we're switching to/from a connected UDP socket */
+
+  adjsock |= ((nmp->nm_flag & NFSMNT_NOCONN) != (argp->flags & NFSMNT_NOCONN));
+
+  /* Update flags atomically.  Don't change the lock bits. */
+
+  nmp->nm_flag =
+    (argp->flags & ~NFSMNT_INTERNAL) | (nmp->nm_flag & NFSMNT_INTERNAL);
+  splx(s);
+
+  if ((argp->flags & NFSMNT_TIMEO) && argp->timeo > 0)
+    {
+      nmp->nm_timeo = (argp->timeo * NFS_HZ + 5) / 10;
+      if (nmp->nm_timeo < NFS_MINTIMEO)
+        nmp->nm_timeo = NFS_MINTIMEO;
+      else if (nmp->nm_timeo > NFS_MAXTIMEO)
+        nmp->nm_timeo = NFS_MAXTIMEO;
+    }
+
+  if ((argp->flags & NFSMNT_RETRANS) && argp->retrans > 1)
+    nmp->nm_retry = MIN(argp->retrans, NFS_MAXREXMIT);
+  if (!(nmp->nm_flag & NFSMNT_SOFT))
+    nmp->nm_retry = NFS_MAXREXMIT + 1;  /* past clip limit */
+
+  if (argp->flags & NFSMNT_NFSV3)
+    {
+      if (argp->sotype == SOCK_DGRAM)
+        maxio = NFS_MAXDGRAMDATA;
+      else
+        maxio = NFS_MAXDATA;
+    }
+  else
+    maxio = NFS_V2MAXDATA;
+
+  if ((argp->flags & NFSMNT_WSIZE) && argp->wsize > 0)
+    {
+      int osize = nmp->nm_wsize;
+      nmp->nm_wsize = argp->wsize;
+
+      /* Round down to multiple of blocksize */
+
+      nmp->nm_wsize &= ~(NFS_FABLKSIZE - 1);
+      if (nmp->nm_wsize <= 0)
+        nmp->nm_wsize = NFS_FABLKSIZE;
+      adjsock |= (nmp->nm_wsize != osize);
+    }
+  if (nmp->nm_wsize > maxio)
+    nmp->nm_wsize = maxio;
+  if (nmp->nm_wsize > MAXBSIZE)
+    nmp->nm_wsize = MAXBSIZE;
+
+  if ((argp->flags & NFSMNT_RSIZE) && argp->rsize > 0)
+    {
+      int osize = nmp->nm_rsize;
+      nmp->nm_rsize = argp->rsize;
+
+      /* Round down to multiple of blocksize */
+
+      nmp->nm_rsize &= ~(NFS_FABLKSIZE - 1);
+      if (nmp->nm_rsize <= 0)
+        nmp->nm_rsize = NFS_FABLKSIZE;
+      adjsock |= (nmp->nm_rsize != osize);
+    }
+  if (nmp->nm_rsize > maxio)
+    nmp->nm_rsize = maxio;
+  if (nmp->nm_rsize > MAXBSIZE)
+    nmp->nm_rsize = MAXBSIZE;
+
+  if ((argp->flags & NFSMNT_READDIRSIZE) && argp->readdirsize > 0)
+    {
+      nmp->nm_readdirsize = argp->readdirsize;
+
+      /* Round down to multiple of blocksize */
+
+      nmp->nm_readdirsize &= ~(NFS_DIRBLKSIZ - 1);
+      if (nmp->nm_readdirsize < NFS_DIRBLKSIZ)
+        nmp->nm_readdirsize = NFS_DIRBLKSIZ;
+    }
+  else if (argp->flags & NFSMNT_RSIZE)
+    nmp->nm_readdirsize = nmp->nm_rsize;
+
+  if (nmp->nm_readdirsize > maxio)
+    nmp->nm_readdirsize = maxio;
+
+  if ((argp->flags & NFSMNT_MAXGRPS) && argp->maxgrouplist >= 0 &&
+      argp->maxgrouplist <= NFS_MAXGRPS)
+    nmp->nm_numgrps = argp->maxgrouplist;
+  if ((argp->flags & NFSMNT_READAHEAD) && argp->readahead >= 0 &&
+      argp->readahead <= NFS_MAXRAHEAD)
+    nmp->nm_readahead = argp->readahead;
+  if (argp->flags & NFSMNT_ACREGMIN && argp->acregmin >= 0)
+    {
+      if (argp->acregmin > 0xffff)
+        nmp->nm_acregmin = 0xffff;
+      else
+        nmp->nm_acregmin = argp->acregmin;
+    }
+  if (argp->flags & NFSMNT_ACREGMAX && argp->acregmax >= 0)
+    {
+      if (argp->acregmax > 0xffff)
+        nmp->nm_acregmax = 0xffff;
+      else
+        nmp->nm_acregmax = argp->acregmax;
+    }
+  if (nmp->nm_acregmin > nmp->nm_acregmax)
+    nmp->nm_acregmin = nmp->nm_acregmax;
+
+  if (argp->flags & NFSMNT_ACDIRMIN && argp->acdirmin >= 0)
+    {
+      if (argp->acdirmin > 0xffff)
+        nmp->nm_acdirmin = 0xffff;
+      else
+        nmp->nm_acdirmin = argp->acdirmin;
+    }
+  if (argp->flags & NFSMNT_ACDIRMAX && argp->acdirmax >= 0)
+    {
+      if (argp->acdirmax > 0xffff)
+        nmp->nm_acdirmax = 0xffff;
+      else
+        nmp->nm_acdirmax = argp->acdirmax;
+    }
+  if (nmp->nm_acdirmin > nmp->nm_acdirmax)
+    nmp->nm_acdirmin = nmp->nm_acdirmax;
+
+  if (nmp->nm_so && adjsock)
+    {
+      nfs_disconnect(nmp);
+      if (nmp->nm_sotype == SOCK_DGRAM)
+        while (nfs_connect(nmp, NULL))
+          {
+            printf("nfs_args: retrying connect\n");
+            (void)tsleep((caddr_t) & lbolt, PSOCK, "nfscon", 0);
+          }
+    }
+
+  /* Update nargp based on nmp */
+
+  nargp->wsize = nmp->nm_wsize;
+  nargp->rsize = nmp->nm_rsize;
+  nargp->readdirsize = nmp->nm_readdirsize;
+  nargp->timeo = nmp->nm_timeo;
+  nargp->retrans = nmp->nm_retry;
+  nargp->maxgrouplist = nmp->nm_numgrps;
+  nargp->readahead = nmp->nm_readahead;
+  nargp->acregmin = nmp->nm_acregmin;
+  nargp->acregmax = nmp->nm_acregmax;
+  nargp->acdirmin = nmp->nm_acdirmin;
+  nargp->acdirmax = nmp->nm_acdirmax;
+}
+
+/* VFS Operations.
+ *
+ * mount system call
+ * It seems a bit dumb to copyinstr() the host and path here and then
+ * bcopy() them in mountnfs(), but I wanted to detect errors before
+ * doing the sockargs() call because sockargs() allocates an mbuf and
+ * an error after that means that I have to release the mbuf.
+ */
+
+/* ARGSUSED */
+int
+nfs_mount(struct mount *mp, const char *path, void *data,
+          struct nameidata *ndp, struct proc *p)
+{
+  int error;
+  struct nfs_args args;
+  struct mbuf *nam;
+  char pth[MNAMELEN], hst[MNAMELEN];
+  size_t len;
+  u_char nfh[NFSX_V3FHMAX];
+
+  error = copyin(data, &args, sizeof(args.version));
+  if (error)
+    return (error);
+  if (args.version == 3)
+    {
+      error = copyin(data, (caddr_t) & args, sizeof(struct nfs_args3));
+      args.flags &= ~(NFSMNT_INTERNAL | NFSMNT_NOAC);
+    }
+  else if (args.version == NFS_ARGSVERSION)
+    {
+      error = copyin(data, (caddr_t) & args, sizeof(struct nfs_args));
+      args.flags &= ~NFSMNT_NOAC;       /* XXX - compatibility */
+    }
+  else
+    return (EPROGMISMATCH);
+  if (error)
+    return (error);
+
+  if ((args.flags & (NFSMNT_NFSV3 | NFSMNT_RDIRPLUS)) == NFSMNT_RDIRPLUS)
+    return (EINVAL);
+
+  if (nfs_niothreads < 0)
+    {
+      nfs_niothreads = 4;
+      nfs_getset_niothreads(1);
+    }
+
+  if (mp->mnt_flag & MNT_UPDATE)
+    {
+      struct nfsmount *nmp = VFSTONFS(mp);
+
+      if (nmp == NULL)
+        return (EIO);
+
+      /* When doing an update, we can't change from or to v3. */
+
+      args.flags = (args.flags & ~(NFSMNT_NFSV3)) |
+        (nmp->nm_flag & (NFSMNT_NFSV3));
+      nfs_decode_args(nmp, &args, &mp->mnt_stat.mount_info.nfs_args);
+      return (0);
+    }
+  if (args.fhsize < 0 || args.fhsize > NFSX_V3FHMAX)
+    return (EINVAL);
+  error = copyin((caddr_t) args.fh, (caddr_t) nfh, args.fhsize);
+  if (error)
+    return (error);
+  error = copyinstr(path, pth, MNAMELEN - 1, &len);
+  if (error)
+    return (error);
+  bzero(&pth[len], MNAMELEN - len);
+  error = copyinstr(args.hostname, hst, MNAMELEN - 1, &len);
+  if (error)
+    return (error);
+  bzero(&hst[len], MNAMELEN - len);
+
+  /* sockargs() call must be after above copyin() calls */
+
+  error = sockargs(&nam, args.addr, args.addrlen, MT_SONAME);
+  if (error)
+    return (error);
+  args.fh = nfh;
+  error = mountnfs(&args, mp, nam, pth, hst);
+  return (error);
+}
+
+/* Common code for mount and mountroot */
+
+int
+mountnfs(struct nfs_args *argp, struct mount *mp, struct mbuf *nam, char *pth,
+         char *hst)
+{
+  struct nfsmount *nmp;
+  int error;
+
+  if (mp->mnt_flag & MNT_UPDATE)
+    {
+      nmp = VFSTONFS(mp);
+
+      /* update paths, file handles, etc, here XXX */
+
+      m_freem(nam);
+      return (0);
+    }
+  else
+    {
+      nmp = malloc(sizeof(struct nfsmount), M_NFSMNT, M_WAITOK | M_ZERO);
+      mp->mnt_data = (qaddr_t) nmp;
+    }
+
+  vfs_getnewfsid(mp);
+  nmp->nm_mountp = mp;
+  nmp->nm_timeo = NFS_TIMEO;
+  nmp->nm_retry = NFS_RETRANS;
+  nmp->nm_wsize = NFS_WSIZE;
+  nmp->nm_rsize = NFS_RSIZE;
+  nmp->nm_readdirsize = NFS_READDIRSIZE;
+  nmp->nm_numgrps = NFS_MAXGRPS;
+  nmp->nm_readahead = NFS_DEFRAHEAD;
+  nmp->nm_fhsize = argp->fhsize;
+  nmp->nm_acregmin = NFS_MINATTRTIMO;
+  nmp->nm_acregmax = NFS_MAXATTRTIMO;
+  nmp->nm_acdirmin = NFS_MINATTRTIMO;
+  nmp->nm_acdirmax = NFS_MAXATTRTIMO;
+  bcopy((caddr_t) argp->fh, (caddr_t) nmp->nm_fh, argp->fhsize);
+  strncpy(&mp->mnt_stat.f_fstypename[0], mp->mnt_vfc->vfc_name, MFSNAMELEN);
+  bcopy(hst, mp->mnt_stat.f_mntfromname, MNAMELEN);
+  bcopy(pth, mp->mnt_stat.f_mntonname, MNAMELEN);
+  bcopy(argp, &mp->mnt_stat.mount_info.nfs_args, sizeof(*argp));
+  nmp->nm_nam = nam;
+  nfs_decode_args(nmp, argp, &mp->mnt_stat.mount_info.nfs_args);
+
+  RB_INIT(&nmp->nm_ntree);
+  TAILQ_INIT(&nmp->nm_reqsq);
+  timeout_set(&nmp->nm_rtimeout, nfs_timer, nmp);
+
+  /* Set up the sockets and per-host congestion */
+
+  nmp->nm_sotype = argp->sotype;
+  nmp->nm_soproto = argp->proto;
+
+  /* For Connection based sockets (TCP,...) defer the connect until
+   * the first request, in case the server is not responding.
+   */
+
+  if (nmp->nm_sotype == SOCK_DGRAM && (error = nfs_connect(nmp, NULL)))
+    goto bad;
+
+  /* This is silly, but it has to be set so that vinifod() works.
+   * We do not want to do an nfs_statfs() here since we can get
+   * stuck on a dead server and we are holding a lock on the mount
+   * point.
+   */
+
+  mp->mnt_stat.f_iosize = NFS_MAXDGRAMDATA;
+
+  return (0);
+bad:
+  nfs_disconnect(nmp);
+  free((caddr_t) nmp, M_NFSMNT);
+  m_freem(nam);
+  return (error);
+}
+
+/* unmount system call */
+
+int nfs_unmount(struct mount *mp, int mntflags, struct proc *p)
+{
+  struct nfsmount *nmp;
+  int error, flags;
+
+  nmp = VFSTONFS(mp);
+  flags = 0;
+
+  if (mntflags & MNT_FORCE)
+    flags |= FORCECLOSE;
+
+  error = vflush(mp, NULL, flags);
+  if (error)
+    return (error);
+
+  nfs_disconnect(nmp);
+  m_freem(nmp->nm_nam);
+  timeout_del(&nmp->nm_rtimeout);
+  free(nmp, M_NFSMNT);
+  return (0);
+}
+
+/* Return root of a filesystem */
+
+int nfs_root(struct mount *mp, struct vnode **vpp)
+{
+  struct nfsmount *nmp;
+  struct nfsnode *np;
+  int error;
+
+  nmp = VFSTONFS(mp);
+  error = nfs_nget(mp, (nfsfh_t *) nmp->nm_fh, nmp->nm_fhsize, &np);
+  if (error)
+    return (error);
+  *vpp = NFSTOV(np);
+  return (0);
+}
+
+/* Flush out the buffer cache */
+
+int nfs_sync(struct mount *mp, int waitfor, struct ucred *cred, struct proc *p)
+{
+  struct vnode *vp;
+  int error, allerror = 0;
+
+  /* Don't traverse the vnode list if we want to skip all of them. */
+
+  if (waitfor == MNT_LAZY)
+    return (allerror);
+
+  /* Force stale buffer cache information to be flushed. */
+
+loop:
+  LIST_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes)
+  {
+    /* If the vnode that we are about to sync is no longer
+     * associated with this mount point, start over.
+     */
+
+    if (vp->v_mount != mp)
+      goto loop;
+    if (VOP_ISLOCKED(vp) || LIST_FIRST(&vp->v_dirtyblkhd) == NULL)
+      continue;
+    if (vget(vp, LK_EXCLUSIVE, p))
+      goto loop;
+    error = VOP_FSYNC(vp, cred, waitfor, p);
+    if (error)
+      allerror = error;
+    vput(vp);
+  }
+
+  return (allerror);
+}
+
+/* NFS flat namespace lookup.
+ * Currently unsupported.
+ */
+
+/* ARGSUSED */
+int nfs_vget(struct mount *mp, ino_t ino, struct vnode **vpp)
+{
+  return (EOPNOTSUPP);
+}
+
+/* Do that sysctl thang... */
+
+int
+nfs_sysctl(int *name, u_int namelen, void *oldp, size_t * oldlenp, void *newp,
+           size_t newlen, struct proc *p)
+{
+  int rv;
+
+  /* All names at this level are terminal. */
+
+  if (namelen > 1)
+    return ENOTDIR;             /* overloaded */
+
+  switch (name[0])
+    {
+    case NFS_NFSSTATS:
+      if (!oldp)
+        {
+          *oldlenp = sizeof nfsstats;
+          return 0;
+        }
+
+      if (*oldlenp < sizeof nfsstats)
+        {
+          *oldlenp = sizeof nfsstats;
+          return ENOMEM;
+        }
+
+      rv = copyout(&nfsstats, oldp, sizeof nfsstats);
+      if (rv)
+        return rv;
+
+      if (newp && newlen != sizeof nfsstats)
+        return EINVAL;
+
+      if (newp)
+        {
+          return copyin(newp, &nfsstats, sizeof nfsstats);
+        }
+      return 0;
+
+    case NFS_NIOTHREADS:
+      nfs_getset_niothreads(0);
+
+      rv = sysctl_int(oldp, oldlenp, newp, newlen, &nfs_niothreads);
+      if (newp)
+        nfs_getset_niothreads(1);
+
+      return rv;
+
+    default:
+      return EOPNOTSUPP;
+    }
+}
+
+/* At this point, this should never happen */
+
+/* ARGSUSED */
+int nfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp)
+{
+  return (EINVAL);
+}
+
+/* Vnode pointer to File handle, should never happen either */
+
+/* ARGSUSED */
+int nfs_vptofh(struct vnode *vp, struct fid *fhp)
+{
+  return (EINVAL);
+}
+
+/* Vfs start routine, a no-op. */
+
+/* ARGSUSED */
+int nfs_start(struct mount *mp, int flags, struct proc *p)
+{
+  return (0);
+}
+
+/* Do operations associated with quotas, not supported */
+
+/* ARGSUSED */
+int
+nfs_quotactl(struct mount *mp, int cmd, uid_t uid, caddr_t arg, struct proc *p)
+{
+  return (EOPNOTSUPP);
+}
+
+/* check export permission, not supported */
+
+/* ARGUSED */
+int
+nfs_checkexp(struct mount *mp, struct mbuf *nam, int *exflagsp,
+             struct ucred **credanonp)
+{
+  return (EOPNOTSUPP);
+}