---

yaml
---
r: 333177
b: refs/heads/master
c: 8965261
h: refs/heads/master
i:
  333175: 81ac6f4
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ba9b584c1dc37851d9c6ca6d0d2ccba55d9aad04
+refs/heads/master: 896526174ce2b6a773e187ebe5a047b68230e2c4

trunk/fs/nfs/client.c

@@ -752,6 +752,8 @@ static int nfs_init_server(struct nfs_server *server,
 			data->timeo, data->retrans);
 	if (data->flags & NFS_MOUNT_NORESVPORT)
 		set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
+	if (server->options & NFS_OPTION_MIGRATION)
+		set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 
 	/* Allocate or find a client reference we can use */
 	clp = nfs_get_client(&cl_init, &timeparms, NULL, RPC_AUTH_UNIX);

trunk/fs/nfs/super.c

@@ -88,6 +88,7 @@ enum {
 	Opt_sharecache, Opt_nosharecache,
 	Opt_resvport, Opt_noresvport,
 	Opt_fscache, Opt_nofscache,
+	Opt_migration, Opt_nomigration,
 
 	/* Mount options that take integer arguments */
 	Opt_port,
@@ -147,6 +148,8 @@ static const match_table_t nfs_mount_option_tokens = {
 	{ Opt_noresvport, "noresvport" },
 	{ Opt_fscache, "fsc" },
 	{ Opt_nofscache, "nofsc" },
+	{ Opt_migration, "migration" },
+	{ Opt_nomigration, "nomigration" },
 
 	{ Opt_port, "port=%s" },
 	{ Opt_rsize, "rsize=%s" },
@@ -676,6 +679,9 @@ static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 	if (nfss->options & NFS_OPTION_FSCACHE)
 		seq_printf(m, ",fsc");
 
+	if (nfss->options & NFS_OPTION_MIGRATION)
+		seq_printf(m, ",migration");
+
 	if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 		if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 			seq_printf(m, ",lookupcache=none");
@@ -1243,6 +1249,12 @@ static int nfs_parse_mount_options(char *raw,
 			kfree(mnt->fscache_uniq);
 			mnt->fscache_uniq = NULL;
 			break;
+		case Opt_migration:
+			mnt->options |= NFS_OPTION_MIGRATION;
+			break;
+		case Opt_nomigration:
+			mnt->options &= NFS_OPTION_MIGRATION;
+			break;
 
 		/*
 		 * options that take numeric values
@@ -1535,6 +1547,10 @@ static int nfs_parse_mount_options(char *raw,
 	if (mnt->minorversion && mnt->version != 4)
 		goto out_minorversion_mismatch;
 
+	if (mnt->options & NFS_OPTION_MIGRATION &&
+	    mnt->version != 4 && mnt->minorversion != 0)
+		goto out_migration_misuse;
+
 	/*
 	 * verify that any proto=/mountproto= options match the address
 	 * familiies in the addr=/mountaddr= options.
@@ -1572,6 +1588,10 @@ static int nfs_parse_mount_options(char *raw,
 	printk(KERN_INFO "NFS: mount option vers=%u does not support "
 			 "minorversion=%u\n", mnt->version, mnt->minorversion);
 	return 0;
+out_migration_misuse:
+	printk(KERN_INFO
+		"NFS: 'migration' not supported for this NFS version\n");
+	return 0;
 out_nomem:
 	printk(KERN_INFO "NFS: not enough memory to parse option\n");
 	return 0;

trunk/include/linux/nfs_fs_sb.h

@@ -39,6 +39,7 @@ struct nfs_client {
 	unsigned long		cl_flags;	/* behavior switches */
 #define NFS_CS_NORESVPORT	0		/* - use ephemeral src port */
 #define NFS_CS_DISCRTRY		1		/* - disconnect on RPC retry */
+#define NFS_CS_MIGRATION	2		/* - transparent state migr */
 	struct sockaddr_storage	cl_addr;	/* server identifier */
 	size_t			cl_addrlen;
 	char *			cl_hostname;	/* hostname of server */
@@ -125,6 +126,7 @@ struct nfs_server {
 	unsigned int		namelen;
 	unsigned int		options;	/* extra options enabled by mount */
 #define NFS_OPTION_FSCACHE	0x00000001	/* - local caching enabled */
+#define NFS_OPTION_MIGRATION	0x00000002	/* - NFSv4 migration enabled */
 
 	struct nfs_fsid		fsid;
 	__u64			maxfilesize;	/* maximum file size */