[src/trunk]: src/sys/nfs Instead of storing the filehandle in the mount struc...

[fvdl <fvdl%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/3e2df74d221e
branches:  trunk
changeset: 503740:3e2df74d221e
user:      fvdl <fvdl%NetBSD.org@localhost>
date:      Mon Feb 12 20:02:30 2001 +0000

description:
Instead of storing the filehandle in the mount structure, store the
vnode pointer. This avoids a locking problem with nfs_nget, and
can be done because we always have a reference on the root vnode
of the filesystem.

diffstat:

 sys/nfs/nfs_vfsops.c |  33 +++++++++++++--------------------
 sys/nfs/nfsmount.h   |   5 ++---
 2 files changed, 15 insertions(+), 23 deletions(-)

diffs (123 lines):

diff -r 92eb29ccb8fb -r 3e2df74d221e sys/nfs/nfs_vfsops.c
--- a/sys/nfs/nfs_vfsops.c      Mon Feb 12 19:49:20 2001 +0000
+++ b/sys/nfs/nfs_vfsops.c      Mon Feb 12 20:02:30 2001 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: nfs_vfsops.c,v 1.100 2001/02/06 11:40:02 fvdl Exp $    */
+/*     $NetBSD: nfs_vfsops.c,v 1.101 2001/02/12 20:02:30 fvdl Exp $    */
 
 /*
  * Copyright (c) 1989, 1993, 1995
@@ -148,16 +148,12 @@
 #endif
        struct mbuf *mreq, *mrep = NULL, *md, *mb, *mb2;
        struct ucred *cred;
-       struct nfsnode *np;
        u_quad_t tquad;
 
 #ifndef nolint
        sfp = (struct nfs_statfs *)0;
 #endif
-       error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
-       if (error)
-               return (error);
-       vp = NFSTOV(np);
+       vp = nmp->nm_vnode;
        cred = crget();
        cred->cr_ngroups = 0;
        if (v3 && (nmp->nm_iflag & NFSMNT_GOTFSINFO) == 0)
@@ -207,7 +203,6 @@
        }
        strncpy(&sbp->f_fstypename[0], mp->mnt_op->vfs_name, MFSNAMELEN);
        nfsm_reqdone;
-       vput(vp);
        crfree(cred);
        return (error);
 }
@@ -682,8 +677,6 @@
        nmp->nm_deadthresh = NQ_DEADTHRESH;
        CIRCLEQ_INIT(&nmp->nm_timerhead);
        nmp->nm_inprog = NULLVP;
-       nmp->nm_fhsize = argp->fhsize;
-       memcpy((caddr_t)nmp->nm_fh, (caddr_t)argp->fh, argp->fhsize);
 #ifdef COMPAT_09
        mp->mnt_stat.f_type = 2;
 #else
@@ -718,7 +711,7 @@
         * point.
         */
        mp->mnt_stat.f_iosize = NFS_MAXDGRAMDATA;
-       error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
+       error = nfs_nget(mp, (nfsfh_t *)argp->fh, argp->fhsize, &np);
        if (error)
                goto bad;
        *vpp = NFSTOV(np);
@@ -741,6 +734,7 @@
         * number == ROOTINO (2). So, just unlock, but no rele.
         */
 
+       nmp->nm_vnode = *vpp;
        VOP_UNLOCK(*vpp, 0);
 
        return (0);
@@ -761,7 +755,6 @@
        struct proc *p;
 {
        struct nfsmount *nmp;
-       struct nfsnode *np;
        struct vnode *vp;
        int error, flags = 0;
 
@@ -782,10 +775,11 @@
         * the remote root.  See comment in mountnfs().  The VFS unmount()
         * has done vput on this vnode, otherwise we would get deadlock!
         */
-       error = nfs_nget(mp, (nfsfh_t *)nmp->nm_fh, nmp->nm_fhsize, &np);
-       if (error)
-               return(error);
-       vp = NFSTOV(np);
+       vp = nmp->nm_vnode;
+       error = vget(vp, LK_EXCLUSIVE | LK_RETRY);
+       if (error != 0)
+               return error;
+
        if ((mntflags & MNT_FORCE) == 0 && vp->v_usecount > 2) {
                vput(vp);
                return (EBUSY);
@@ -839,14 +833,13 @@
 {
        struct vnode *vp;
        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);
-       vp = NFSTOV(np);
+       vp = nmp->nm_vnode;
+       error = vget(vp, LK_EXCLUSIVE | LK_RETRY);
+       if (error != 0)
+               return error;
        if (vp->v_type == VNON)
                vp->v_type = VDIR;
        vp->v_flag = VROOT;
diff -r 92eb29ccb8fb -r 3e2df74d221e sys/nfs/nfsmount.h
--- a/sys/nfs/nfsmount.h        Mon Feb 12 19:49:20 2001 +0000
+++ b/sys/nfs/nfsmount.h        Mon Feb 12 20:02:30 2001 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: nfsmount.h,v 1.19 2000/03/16 18:08:31 jdolecek Exp $   */
+/*     $NetBSD: nfsmount.h,v 1.20 2001/02/12 20:02:30 fvdl Exp $       */
 
 /*
  * Copyright (c) 1989, 1993
@@ -119,8 +119,7 @@
        int     nm_flag;                /* Flags for soft/hard... */
        struct  mount *nm_mountp;       /* Vfs structure for this filesystem */
        int     nm_numgrps;             /* Max. size of groupslist */
-       u_char  nm_fh[NFSX_V3FHMAX];    /* File handle of root dir */
-       int     nm_fhsize;              /* Size of root file handle */
+       struct vnode *nm_vnode;
        struct  socket *nm_so;          /* Rpc socket */
        int     nm_sotype;              /* Type of socket */
        int     nm_soproto;             /* and protocol */