When using NFSv3, use the remote server's idea of the maximum file size

rather than assuming 2^64.  It may not like files that big. :-)
On the nfs server, calculate and report the max file size as the point
that the block numbers in the cache would turn negative.
(ie: 1099511627775 bytes (1TB)).

One of the things I'm worried about however, is that directory offsets
are really cookies on a NFSv3 server and can be rather large, especially
when/if the server generates the opaque directory cookies by using a local
filesystem offset in what comes out as the upper 32 bits of the 64 bit
cookie.  (a server is free to do this, it could save byte swapping
depending on the native 64 bit byte order)

Obtained from:	NetBSD

4 files changed, 26 insertions, 7 deletions

diff --git a/sys/nfsclient/nfs_bio.c b/sys/nfsclient/nfs_bio.c
index d16bf1a..d98bc7f 100644
--- a/sys/nfsclient/nfs_bio.c
+++ b/sys/nfsclient/nfs_bio.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)nfs_bio.c	8.9 (Berkeley) 3/30/95
- * $Id: nfs_bio.c,v 1.55 1998/05/19 07:11:22 peter Exp $
+ * $Id: nfs_bio.c,v 1.56 1998/05/20 08:02:23 peter Exp $
  */
 
 
@@ -254,12 +254,15 @@ nfs_bioread(vp, uio, ioflag, cred, getpages)
 #endif
 	if (uio->uio_resid == 0)
 		return (0);
-	if (uio->uio_offset < 0)
+	if (uio->uio_offset < 0)	/* XXX VDIR cookies can be negative */
 		return (EINVAL);
 	p = uio->uio_procp;
 	if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 &&
 	    (nmp->nm_state & NFSSTA_GOTFSINFO) == 0)
 		(void)nfs_fsinfo(nmp, vp, cred, p);
+	if (vp->v_type != VDIR &&
+	    (uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize)
+		return (EFBIG);
 	biosize = vp->v_mount->mnt_stat.f_iosize;
 	/*
 	 * For nfs, cache consistency can only be maintained approximately.
@@ -657,6 +660,8 @@ nfs_write(ap)
 	}
 	if (uio->uio_offset < 0)
 		return (EINVAL);
+	if ((uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize)
+		return (EFBIG);
 	if (uio->uio_resid == 0)
 		return (0);
 	/*
diff --git a/sys/nfsclient/nfs_vfsops.c b/sys/nfsclient/nfs_vfsops.c
index 729ccba..554b0ef 100644
--- a/sys/nfsclient/nfs_vfsops.c
+++ b/sys/nfsclient/nfs_vfsops.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)nfs_vfsops.c	8.12 (Berkeley) 5/20/95
- * $Id: nfs_vfsops.c,v 1.62 1998/05/20 08:05:45 peter Exp $
+ * $Id: nfs_vfsops.c,v 1.63 1998/05/24 14:41:56 peter Exp $
  */
 
 #include <sys/param.h>
@@ -333,6 +333,7 @@ nfs_fsinfo(nmp, vp, cred, p)
 	caddr_t bpos, dpos, cp2;
 	int error = 0, retattr;
 	struct mbuf *mreq, *mrep, *md, *mb, *mb2;
+	u_int64_t maxfsize;
 
 	nfsstats.rpccnt[NFSPROC_FSINFO]++;
 	nfsm_reqhead(vp, NFSPROC_FSINFO, NFSX_FH(1));
@@ -367,6 +368,11 @@ nfs_fsinfo(nmp, vp, cred, p)
 		if (max < nmp->nm_readdirsize) {
 			nmp->nm_readdirsize = max;
 		}
+		/* XXX */
+		nmp->nm_maxfilesize = (u_int64_t)0x80000000 * DEV_BSIZE - 1;
+		fxdr_hyper(&fsp->fs_maxfilesize, &maxfsize);
+		if (maxfsize > 0 && maxfsize < nmp->nm_maxfilesize)
+			nmp->nm_maxfilesize = maxfsize;
 		nmp->nm_state |= NFSSTA_GOTFSINFO;
 	}
 	nfsm_reqdone;
@@ -690,6 +696,13 @@ mountnfs(argp, mp, nam, pth, hst, vpp)
 		 * unsuspecting binaries).
 		 */
 		mp->mnt_maxsymlinklen = 1;
+	if ((argp->flags & NFSMNT_NFSV3) == 0)
+		/*
+		 * V2 can only handle 32 bit filesizes. For v3, nfs_fsinfo
+		 * will fill this in.
+		 */
+		nmp->nm_maxfilesize = 0xffffffffLL;
+
 	nmp->nm_timeo = NFS_TIMEO;
 	nmp->nm_retry = NFS_RETRANS;
 	nmp->nm_wsize = NFS_WSIZE;
diff --git a/sys/nfsclient/nfs_vnops.c b/sys/nfsclient/nfs_vnops.c
index 246757f..dc8629d 100644
--- a/sys/nfsclient/nfs_vnops.c
+++ b/sys/nfsclient/nfs_vnops.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)nfs_vnops.c	8.16 (Berkeley) 5/27/95
- * $Id: nfs_vnops.c,v 1.88 1998/05/16 16:20:50 bde Exp $
+ * $Id: nfs_vnops.c,v 1.89 1998/05/19 07:11:26 peter Exp $
  */
 
 
@@ -1029,7 +1029,7 @@ nfs_readrpc(vp, uiop, cred)
 #endif
 	nmp = VFSTONFS(vp->v_mount);
 	tsiz = uiop->uio_resid;
-	if (uiop->uio_offset + tsiz > 0xffffffff && !v3)
+	if (uiop->uio_offset + tsiz > nmp->nm_maxfilesize)
 		return (EFBIG);
 	while (tsiz > 0) {
 		nfsstats.rpccnt[NFSPROC_READ]++;
@@ -1095,7 +1095,7 @@ nfs_writerpc(vp, uiop, cred, iomode, must_commit)
 #endif
 	*must_commit = 0;
 	tsiz = uiop->uio_resid;
-	if (uiop->uio_offset + tsiz > 0xffffffff && !v3)
+	if (uiop->uio_offset + tsiz > nmp->nm_maxfilesize)
 		return (EFBIG);
 	while (tsiz > 0) {
 		nfsstats.rpccnt[NFSPROC_WRITE]++;
diff --git a/sys/nfsclient/nfsmount.h b/sys/nfsclient/nfsmount.h
index 2d502bd..ecb4f05 100644
--- a/sys/nfsclient/nfsmount.h
+++ b/sys/nfsclient/nfsmount.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)nfsmount.h	8.3 (Berkeley) 3/30/95
- * $Id: nfsmount.h,v 1.13 1997/08/16 19:16:05 wollman Exp $
+ * $Id: nfsmount.h,v 1.14 1998/05/19 07:11:27 peter Exp $
  */
 
 
@@ -92,6 +92,7 @@ struct	nfsmount {
 	short	nm_bufqlen;		/* number of buffers in queue */
 	short	nm_bufqwant;		/* process wants to add to the queue */
 	int	nm_bufqiods;		/* number of iods processing queue */
+	u_int64_t nm_maxfilesize;	/* maximum file size */
 };
 
 #if defined(KERNEL) || defined(_KERNEL)