* Copyright (c) 1989 The Regents of the University of California.
* 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 are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
* @(#)nfs_vfsops.c 7.18 (Berkeley) %G%
struct vfsops nfs_vfsops
= {
* Called by vfs_mountroot when nfs is going to be mounted as root
* Not Yet (By a LONG shot)
* 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.
nfs_mount(mp
, path
, data
, ndp
)
char pth
[MNAMELEN
], hst
[MNAMELEN
];
if (mp
->m_flag
& M_UPDATE
)
if (error
= copyin(data
, (caddr_t
)&args
, sizeof (struct nfs_args
)))
if (error
=copyin((caddr_t
)args
.fh
, (caddr_t
)&nfh
, sizeof (nfsv2fh_t
)))
if (error
= copyinstr(path
, pth
, MNAMELEN
-1, &len
))
bzero(&pth
[len
], MNAMELEN
-len
);
if (error
= copyinstr(args
.hostname
, hst
, MNAMELEN
-1, &len
))
bzero(&hst
[len
], MNAMELEN
-len
);
/* sockargs() call must be after above copyin() calls */
if (error
= sockargs(&saddr
, (caddr_t
)args
.addr
,
sizeof (struct sockaddr
), MT_SONAME
))
error
= mountnfs(&args
, mp
, saddr
, pth
, hst
);
* Common code for mount and mountroot
mountnfs(argp
, mp
, saddr
, pth
, hst
)
register struct nfs_args
*argp
;
register struct mount
*mp
;
register struct mbuf
*saddr
;
register struct nfsmount
*nmp
;
MALLOC(nmp
, struct nfsmount
*, sizeof *nmp
, M_NFSMNT
, M_WAITOK
);
bzero((caddr_t
)nmp
, sizeof *nmp
);
mp
->m_data
= (qaddr_t
)nmp
;
* Generate a unique nfs mount id. The problem is that a dev number
* is not unique across multiple systems. The techique is as follows:
* 1) Set to nblkdev,0 which will never be used otherwise
* 2) Generate a first guess as nblkdev,nfs_mntid where nfs_mntid is
* 3) Loop searching the mount list for another one with same id
* If a match, increment val[0] and try again
* NB: I increment val[0] { a long } instead of nfs_mntid { a u_char }
* so that nfs is not limited to 255 mount points
* Incrementing the high order bits does no real harm, since it
* simply makes the major dev number tick up. The upper bound is
* set to major dev 127 to avoid any sign extention problems
mp
->m_stat
.f_fsid
.val
[0] = makedev(nblkdev
, 0);
mp
->m_stat
.f_fsid
.val
[1] = MOUNT_NFS
;
tfsid
.val
[0] = makedev(nblkdev
, nfs_mntid
);
tfsid
.val
[1] = MOUNT_NFS
;
if (major(tfsid
.val
[0]) > 127) {
mp
->m_stat
.f_fsid
.val
[0] = tfsid
.val
[0];
nmp
->nm_flag
= argp
->flags
;
nmp
->nm_rttvar
= nmp
->nm_rto
<< 1;
nmp
->nm_retry
= NFS_RETRANS
;
nmp
->nm_wsize
= NFS_WSIZE
;
nmp
->nm_rsize
= NFS_RSIZE
;
bcopy((caddr_t
)argp
->fh
, (caddr_t
)&nmp
->nm_fh
, sizeof(nfsv2fh_t
));
bcopy(hst
, mp
->m_stat
.f_mntfromname
, MNAMELEN
);
bcopy(pth
, mp
->m_stat
.f_mntonname
, MNAMELEN
);
if ((argp
->flags
& NFSMNT_TIMEO
) && argp
->timeo
> 0) {
nmp
->nm_rto
= argp
->timeo
;
/* NFS timeouts are specified in 1/10 sec. */
nmp
->nm_rto
= (nmp
->nm_rto
* 10) / NFS_HZ
;
if (nmp
->nm_rto
< NFS_MINTIMEO
)
nmp
->nm_rto
= NFS_MINTIMEO
;
else if (nmp
->nm_rto
> NFS_MAXTIMEO
)
nmp
->nm_rto
= NFS_MAXTIMEO
;
nmp
->nm_rttvar
= nmp
->nm_rto
<< 1;
if ((argp
->flags
& NFSMNT_RETRANS
) && argp
->retrans
>= 0) {
nmp
->nm_retry
= argp
->retrans
;
if (nmp
->nm_retry
> NFS_MAXREXMIT
)
nmp
->nm_retry
= NFS_MAXREXMIT
;
if ((argp
->flags
& NFSMNT_WSIZE
) && argp
->wsize
> 0) {
nmp
->nm_wsize
= argp
->wsize
;
/* Round down to multiple of blocksize */
else if (nmp
->nm_wsize
> NFS_MAXDATA
)
nmp
->nm_wsize
= NFS_MAXDATA
;
if ((argp
->flags
& NFSMNT_RSIZE
) && argp
->rsize
> 0) {
nmp
->nm_rsize
= argp
->rsize
;
/* Round down to multiple of blocksize */
else if (nmp
->nm_rsize
> NFS_MAXDATA
)
nmp
->nm_rsize
= NFS_MAXDATA
;
/* Set up the sockets and per-host congestion */
if (error
= nfs_connect(nmp
, saddr
)) {
if (error
= nfs_statfs(mp
, &mp
->m_stat
))
* A reference count is needed on the nfsnode representing the
* remote root. If this object is not persistent, then backward
* traversals of the mount point (i.e. "..") will not work if
* the nfsnode gets flushed out of the cache. Ufs does not have
* this problem, because one can identify root inodes by their
if (error
= nfs_nget(mp
, &nmp
->nm_fh
, &np
))
* Unlock it, but keep the reference count.
register struct nfsmount
*nmp
;
register struct nfsreq
*rep
;
* Clear out the buffer cache
* 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.
* - Decrement reference on the vnode representing remote root.
* - 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!
if (error
= nfs_nget(mp
, &nmp
->nm_fh
, &np
))
if (vp
->v_usecount
> 2) {
if (error
= vflush(mp
, vp
, flags
)) {
* Get rid of two reference counts, and unlock it on the second.
free((caddr_t
)nmp
, M_NFSMNT
);
* Return root of a filesystem
register struct vnode
*vp
;
if (error
= nfs_nget(mp
, &nmp
->nm_fh
, &np
))
* Flush out the buffer cache
* Force stale buffer cache information to be flushed.
mntflushbuf(mp
, waitfor
== MNT_WAIT
? B_SYNC
: 0);
* At this point, this should never happen
* Vnode pointer to File handle, should never happen either
* Vfs start routine, a no-op.