NFSD: Adds macro EX_UUID_LEN for exports uuid's length

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/export.c

@@ -487,10 +487,10 @@ uuid_parse(char **mesg, char *buf, unsigned char **puuid)
 
 	/* expect a 16 byte uuid encoded as \xXXXX... */
 	len = qword_get(mesg, buf, PAGE_SIZE);
-	if (len != 16)
+	if (len != EX_UUID_LEN)
 		return -EINVAL;
 
-	*puuid = kmemdup(buf, 16, GFP_KERNEL);
+	*puuid = kmemdup(buf, EX_UUID_LEN, GFP_KERNEL);
 	if (*puuid == NULL)
 		return -ENOMEM;
 
@@ -663,7 +663,7 @@ static int svc_export_show(struct seq_file *m,
 		if (exp->ex_uuid) {
 			int i;
 			seq_puts(m, ",uuid=");
-			for (i=0; i<16; i++) {
+			for (i = 0; i < EX_UUID_LEN; i++) {
 				if ((i&3) == 0 && i)
 					seq_putc(m, ':');
 				seq_printf(m, "%02x", exp->ex_uuid[i]);

fs/nfsd/export.h

@@ -37,6 +37,7 @@ struct nfsd4_fs_locations {
  * spkm3i, and spkm3p (and using all 8 at once should be rare).
  */
 #define MAX_SECINFO_LIST	8
+#define EX_UUID_LEN		16
 
 struct exp_flavor_info {
 	u32	pseudoflavor;

fs/nfsd/nfs4xdr.c

@@ -2223,7 +2223,8 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
 			*p++ = cpu_to_be32(MINOR(stat.dev));
 			break;
 		case FSIDSOURCE_UUID:
-			p = xdr_encode_opaque_fixed(p, exp->ex_uuid, 16);
+			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
+								EX_UUID_LEN);
 			break;
 		}
 	}