xnu-201.tar.gz

[apple/xnu.git] / bsd / nfs / nfs_vfsops.c

diff --git a/bsd/nfs/nfs_vfsops.c b/bsd/nfs/nfs_vfsops.c
index 1df71854cc36f8c1f2e927e17385249b05d7145f..9c1c7caadd8cfcdc847d7955f962d82e0a265de8 100644 (file)
--- a/bsd/nfs/nfs_vfsops.c
+++ b/bsd/nfs/nfs_vfsops.c
@@ -608,6 +608,11 @@ nfs_mount_diskless_private(ndmntp, mntname, mntflag, vpp, mpp)
         */
        mp = _MALLOC_ZONE((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK);
        bzero((char *)mp, (u_long)sizeof(struct mount));
+
+    /* Initialize the default IO constraints */
+    mp->mnt_maxreadcnt = mp->mnt_maxwritecnt = MAXPHYS;
+    mp->mnt_segreadcnt = mp->mnt_segwritecnt = 32;
+
        lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, 0);
        (void)vfs_busy(mp, LK_NOWAIT, 0, procp);
        LIST_INIT(&mp->mnt_vnodelist);
@@ -936,32 +941,43 @@ nfs_unmount(mp, mntflags, p)
        nmp = VFSTONFS(mp);
        /*
         * Goes something like this..
-        * - Check for activity on the root vnode (other than ourselves).
         * - Call vflush() to clear out vnodes for this file system,
-        *   except for the root vnode.
+        *   except for the swap files. Deal with them in 2nd pass.
+        *   It will do vgone making the vnode VBAD at that time.
         * - Decrement reference on the vnode representing remote root.
         * - Close the socket
         * - Free up the data structures
-        */
-       /*
+        *
         * We need to decrement the ref. count on the nfsnode representing
         * the remote root.  See comment in mountnfs().  The VFS unmount()
         * has done vput on this vnode, otherwise we would get deadlock!
         */
        vp = nmp->nm_dvp;
        vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
-       if (vp->v_usecount > 1) {
-               VOP_UNLOCK(vp, 0, p);
-               return (EBUSY);
-       }
-
+       
        /*
         * Must handshake with nqnfs_clientd() if it is active.
         */
        nmp->nm_flag |= NFSMNT_DISMINPROG;
        while (nmp->nm_inprog != NULLVP)
                (void) tsleep((caddr_t)&lbolt, PSOCK, "nfsdism", 0);
-       error = vflush(mp, vp, flags);
+       /*
+        * vflush will check for busy vnodes on mountpoint. 
+        * Will do the right thing for MNT_FORCE. That is, we should
+        * not get EBUSY back.
+        */
+       error = vflush(mp, vp, SKIPSWAP | flags);
+       if (mntflags & MNT_FORCE) 
+               error = vflush(mp, NULLVP, flags);
+       else {
+               if (vp->v_usecount > 1) {
+                       VOP_UNLOCK(vp, 0, p);
+                       nmp->nm_flag &= ~NFSMNT_DISMINPROG;
+                       return (EBUSY);
+               }
+               error = vflush(mp, vp, flags);
+       }
+
        if (error) {
                VOP_UNLOCK(vp, 0, p);
                nmp->nm_flag &= ~NFSMNT_DISMINPROG;
@@ -977,9 +993,13 @@ nfs_unmount(mp, mntflags, p)
 
        /*
         * Release the root vnode reference held by mountnfs()
+        * Note: vflush would have done the vgone for us if we
+        * didn't skip over it due to mount reference held.
         */
        vput(vp);
-       vgone(vp);
+       if (!(mntflags & MNT_FORCE))
+               vgone(vp);
+       mp->mnt_data = 0; /* don't want to end up using stale vp */
        nfs_disconnect(nmp);
        m_freem(nmp->nm_nam);