[PATCH] knfsd: Allow run-time selection of NFS versions to export

Provide a file in the NFSD filesystem that allows setting and querying of
which version of NFS are being exported.  Changes are only allowed while no
server is running.

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 18 insertions, 1 deletions

diff --git a/include/linux/nfsd/nfsd.h b/include/linux/nfsd/nfsd.h
index 6d5a24f3fc6d..51c231a1e5a6 100644
--- a/include/linux/nfsd/nfsd.h
+++ b/include/linux/nfsd/nfsd.h
@@ -60,7 +60,7 @@ typedef int (*nfsd_dirop_t)(struct inode *, struct dentry *, int, int);
 extern struct svc_program       nfsd_program;
 extern struct svc_version       nfsd_version2, nfsd_version3,
                                 nfsd_version4;
-
+extern struct svc_serv          *nfsd_serv;
 /*
  * Function prototypes.
  */
diff --git a/include/linux/nfsd/syscall.h b/include/linux/nfsd/syscall.h
index e65c9db6d13f..781efbf94ed3 100644
--- a/include/linux/nfsd/syscall.h
+++ b/include/linux/nfsd/syscall.h
@@ -39,6 +39,21 @@
 #define NFSCTL_GETFD            7       /* get an fh by path (used by mountd) */
 #define NFSCTL_GETFS            8       /* get an fh by path with max FH len */
 
+/*
+ * Macros used to set version
+ */
+#define NFSCTL_VERSET(_cltbits, _v)   ((_cltbits) |=  (1 << (_v)))
+#define NFSCTL_VERUNSET(_cltbits, _v) ((_cltbits) &= ~(1 << (_v)))
+#define NFSCTL_VERISSET(_cltbits, _v) ((_cltbits) & (1 << (_v)))
+
+#if defined(CONFIG_NFSD_V4)
+#define NFSCTL_VERALL   (0x1c /* 0b011100 */)
+#elif defined(CONFIG_NFSD_V3)
+#define NFSCTL_VERALL   (0x0c /* 0b001100 */)
+#else
+#define NFSCTL_VERALL   (0x04 /* 0b000100 */)
+#endif
+
 /* SVC */
 struct nfsctl_svc {
         unsigned short          svc_port;
@@ -120,6 +135,8 @@ extern int		exp_delclient(struct nfsctl_client *ncp);
 extern int              exp_export(struct nfsctl_export *nxp);
 extern int              exp_unexport(struct nfsctl_export *nxp);
 
+extern unsigned int nfsd_versbits;
+
 #endif /* __KERNEL__ */
 
 #endif /* NFSD_SYSCALL_H */