[PATCH] A basic NFSv4 client for 2.5.x

In NFSv4, an fsid is a 64-bit major number together with a 64-bit
minor number.  In previous versions, an fsid is a single number.
This patch changes 'struct nfs_fattr' accordingly.

fs/nfs/nfs2xdr.c

@@ -107,7 +107,7 @@ xdr_decode_fattr(u32 *p, struct nfs_fattr *fattr)
 	fattr->du.nfs2.blocksize = ntohl(*p++);
 	fattr->rdev = ntohl(*p++);
 	fattr->du.nfs2.blocks = ntohl(*p++);
-	fattr->fsid = ntohl(*p++);
+	fattr->fsid_u.nfs3 = ntohl(*p++);
 	fattr->fileid = ntohl(*p++);
 	p = xdr_decode_time(p, &fattr->atime);
 	p = xdr_decode_time(p, &fattr->mtime);

fs/nfs/nfs3xdr.c

@@ -173,7 +173,7 @@ xdr_decode_fattr(u32 *p, struct nfs_fattr *fattr)
 	/* Turn remote device info into Linux-specific dev_t */
 	fattr->rdev = ntohl(*p++) << MINORBITS;
 	fattr->rdev |= ntohl(*p++) & MINORMASK;
-	p = xdr_decode_hyper(p, &fattr->fsid);
+	p = xdr_decode_hyper(p, &fattr->fsid_u.nfs3);
 	p = xdr_decode_hyper(p, &fattr->fileid);
 	p = xdr_decode_time3(p, &fattr->atime);
 	p = xdr_decode_time3(p, &fattr->mtime);

include/linux/nfs_xdr.h

@@ -24,7 +24,13 @@ struct nfs_fattr {
 		} nfs3;
 	} du;
 	__u32			rdev;
-	__u64			fsid;
+	union {
+		__u64		nfs3;		/* also nfs2 */
+		struct {
+			__u64	major;
+			__u64	minor;
+		} nfs4;
+	} fsid_u;
 	__u64			fileid;
 	__u64			atime;
 	__u64			mtime;