[PATCH] prepare for 32-bit dev_t: NFS

	NFS made dev_t-agnostic.  Aside of minor fixes in debugging printks,
and adding old_encode_dev()/old_decode_dev(), the main part is in handling
of exports with large dev_t.  New fhandle format introduced, fh_verify(),
fh_compose() and exports cache taught to deal with it.  Format is used when
->s_dev of exported fs doesn't fit into 256:256; in that case we put major
and minor in separate words in fhandle; ->fh_fsid_type is set to 2.

3 files changed, 19 insertions, 21 deletions

diff --git a/include/linux/nfsd/export.h b/include/linux/nfsd/export.h
index 74272d6a562e..204294616cf1 100644
--- a/include/linux/nfsd/export.h
+++ b/include/linux/nfsd/export.h
@@ -65,7 +65,7 @@ struct svc_expkey {
 
 	struct auth_domain *	ek_client;
 	int			ek_fsidtype;
-	u32			ek_fsid[2];
+	u32			ek_fsid[3];
 
 	struct svc_export *	ek_export;
 };
diff --git a/include/linux/nfsd/nfsd.h b/include/linux/nfsd/nfsd.h
index 8c4fb5cfff21..97a57608a6e6 100644
--- a/include/linux/nfsd/nfsd.h
+++ b/include/linux/nfsd/nfsd.h
@@ -15,6 +15,7 @@
 #include <linux/unistd.h>
 #include <linux/dirent.h>
 #include <linux/fs.h>
+#include <linux/mount.h>
 
 #include <linux/nfsd/debug.h>
 #include <linux/nfsd/nfsfh.h>
@@ -209,6 +210,17 @@ void		nfsd_lockd_shutdown(void);
  */
 extern struct timeval	nfssvc_boot;
 
+static inline int is_fsid(struct svc_fh *fh, struct knfsd_fh *reffh)
+{
+	if (fh->fh_export->ex_flags & NFSEXP_FSID) {
+		struct vfsmount *mnt = fh->fh_export->ex_mnt;
+		if (!old_valid_dev(mnt->mnt_sb->s_dev) ||
+		    (reffh->fh_version == 1 && reffh->fh_fsid_type == 1))
+			return 1;
+	}
+	return 0;
+}
+
 
 #ifdef CONFIG_NFSD_V4
 
diff --git a/include/linux/nfsd/nfsfh.h b/include/linux/nfsd/nfsfh.h
index d4d63cc8e5fa..555793d69ddc 100644
--- a/include/linux/nfsd/nfsfh.h
+++ b/include/linux/nfsd/nfsfh.h
@@ -117,26 +117,6 @@ struct knfsd_fh {
 
 #ifdef __KERNEL__
 
-/*
- * Conversion macros for the filehandle fields.
- *
- * Keep the device numbers in "backwards compatible
- * format", ie the low 16 bits contain the low 8 bits
- * of the 20-bit minor and the 12-bit major number.
- *
- * The high 16 bits contain the rest (4 bits major
- * and 12 bits minor),
- */
-
-static inline dev_t u32_to_dev_t(__u32 udev)
-{
-	unsigned int minor, major;
-
-	minor = (udev & 0xff) | ((udev >> 8) & 0xfff00);
-	major = ((udev >> 8) & 0xff) | ((udev >> 20) & 0xf00);
-	return MKDEV(major, minor);
-}
-
 static inline __u32 ino_t_to_u32(ino_t ino)
 {
 	return (__u32) ino;
@@ -196,6 +176,12 @@ static inline void mk_fsid_v1(u32 *fsidv, u32 fsid)
 	fsidv[0] = fsid;
 }
 
+static inline void mk_fsid_v2(u32 *fsidv, dev_t dev, ino_t ino)
+{
+	fsidv[0] = htonl(MAJOR(dev));
+	fsidv[1] = htonl(MINOR(dev));
+	fsidv[2] = ino_t_to_u32(ino);
+}
 
 /*
  * Shorthand for dprintk()'s