[PATCH v3, RESEND 13/16] nfs: introduce mount option 'rpcmount'

["Kirill A. Shutemov" <kas@openvz.org>]

It specifies rpc_pipefs to use. /var/lib/nfs/rpc_pipefs, by default.

Signed-off-by: Kirill A. Shutemov <kas@openvz.org>
Reviewed-by: Rob Landley <rlandley@parallels.com>
---
 fs/nfs/callback.c         |    5 ++-
 fs/nfs/callback.h         |    3 +-
 fs/nfs/client.c           |   46 ++++++++++++++++++++++++++++++++++++--------
 fs/nfs/internal.h         |   10 +++++++-
 fs/nfs/mount_clnt.c       |    3 +-
 fs/nfs/namespace.c        |    3 +-
 fs/nfs/nfs4namespace.c    |   22 +++++++++++---------
 fs/nfs/super.c            |   20 +++++++++++++++++++
 include/linux/nfs_fs_sb.h |    1 +
 9 files changed, 86 insertions(+), 27 deletions(-)

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index c9b98ad..d56f402 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -245,7 +245,8 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 /*
  * Bring up the callback thread if it is not already up.
  */
-int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
+int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt,
+		struct vfsmount *rpcmount)
 {
 	struct svc_serv *serv = NULL;
 	struct svc_rqst *rqstp;
@@ -260,7 +261,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 		nfs_callback_bc_serv(minorversion, xprt, cb_info);
 		goto out;
 	}
-	serv = svc_create(&nfs4_callback_program, init_rpc_pipefs,
+	serv = svc_create(&nfs4_callback_program, rpcmount,
 			NFS4_CALLBACK_BUFSIZE, NULL);
 	if (!serv) {
 		ret = -ENOMEM;
diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index 46d93ce..0ea5d1e 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -175,7 +175,8 @@ extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
 extern __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
 				   struct cb_process_state *cps);
 #ifdef CONFIG_NFS_V4
-extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt);
+extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt,
+		struct vfsmount *rpcmount);
 extern void nfs_callback_down(int minorversion);
 extern int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation,
 					    const nfs4_stateid *stateid);
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 79c01f8..63e3b54 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -131,6 +131,7 @@ struct nfs_client_initdata {
 	const struct nfs_rpc_ops *rpc_ops;
 	int proto;
 	u32 minorversion;
+	struct vfsmount *rpcmount;
 };
 
 /*
@@ -167,6 +168,7 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_
 	clp->cl_rpcclient = ERR_PTR(-EINVAL);
 
 	clp->cl_proto = cl_init->proto;
+	clp->cl_rpcmount = mntget(cl_init->rpcmount);
 
 #ifdef CONFIG_NFS_V4
 	err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
@@ -286,6 +288,7 @@ static void nfs_free_client(struct nfs_client *clp)
 	if (clp->cl_machine_cred != NULL)
 		put_rpccred(clp->cl_machine_cred);
 
+	mntput(clp->cl_rpcmount);
 	kfree(clp->cl_hostname);
 	kfree(clp);
 
@@ -471,6 +474,9 @@ static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *dat
 		/* Match the full socket address */
 		if (!nfs_sockaddr_cmp(sap, clap))
 			continue;
+		/* Match rpc_pipefs mount point */
+		if (clp->cl_rpcmount->mnt_sb != data->rpcmount->mnt_sb)
+			continue;
 
 		atomic_inc(&clp->cl_count);
 		return clp;
@@ -629,7 +635,7 @@ static int nfs_create_rpc_client(struct nfs_client *clp,
 		.program	= &nfs_program,
 		.version	= clp->rpc_ops->version,
 		.authflavor	= flavor,
-		.rpcmount	= init_rpc_pipefs,
+		.rpcmount	= clp->cl_rpcmount,
 	};
 
 	if (discrtry)
@@ -664,7 +670,7 @@ static void nfs_destroy_server(struct nfs_server *server)
 /*
  * Version 2 or 3 lockd setup
  */
-static int nfs_start_lockd(struct nfs_server *server)
+static int nfs_start_lockd(struct nfs_server *server, struct vfsmount *rpcmount)
 {
 	struct nlm_host *host;
 	struct nfs_client *clp = server->nfs_client;
@@ -675,7 +681,7 @@ static int nfs_start_lockd(struct nfs_server *server)
 		.nfs_version	= clp->rpc_ops->version,
 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
 					1 : 0,
-		.rpcmount	= init_rpc_pipefs,
+		.rpcmount	= rpcmount,
 	};
 
 	if (nlm_init.nfs_version > 3)
@@ -823,8 +829,16 @@ static int nfs_init_server(struct nfs_server *server,
 		cl_init.rpc_ops = &nfs_v3_clientops;
 #endif
 
+	cl_init.rpcmount = get_rpc_pipefs(data->rpcmount);
+	if (IS_ERR(cl_init.rpcmount)) {
+		dprintk("<-- nfs_init_server() = error %ld\n",
+				PTR_ERR(cl_init.rpcmount));
+		return PTR_ERR(cl_init.rpcmount);
+	}
+
 	/* Allocate or find a client reference we can use */
 	clp = nfs_get_client(&cl_init);
+	mntput(cl_init.rpcmount);
 	if (IS_ERR(clp)) {
 		dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
 		return PTR_ERR(clp);
@@ -856,7 +870,7 @@ static int nfs_init_server(struct nfs_server *server,
 	server->acdirmax = data->acdirmax * HZ;
 
 	/* Start lockd here, before we might error out */
-	error = nfs_start_lockd(server);
+	error = nfs_start_lockd(server, clp->cl_rpcmount);
 	if (error < 0)
 		goto error;
 
@@ -1265,7 +1279,8 @@ static int nfs4_init_callback(struct nfs_client *clp)
 		}
 
 		error = nfs_callback_up(clp->cl_mvops->minor_version,
-					clp->cl_rpcclient->cl_xprt);
+					clp->cl_rpcclient->cl_xprt,
+					clp->cl_rpcmount);
 		if (error < 0) {
 			dprintk("%s: failed to start callback. Error = %d\n",
 				__func__, error);
@@ -1365,7 +1380,8 @@ static int nfs4_set_client(struct nfs_server *server,
 		const char *ip_addr,
 		rpc_authflavor_t authflavour,
 		int proto, const struct rpc_timeout *timeparms,
-		u32 minorversion)
+		u32 minorversion,
+		struct vfsmount *rpcmount)
 {
 	struct nfs_client_initdata cl_init = {
 		.hostname = hostname,
@@ -1374,6 +1390,7 @@ static int nfs4_set_client(struct nfs_server *server,
 		.rpc_ops = &nfs_v4_clientops,
 		.proto = proto,
 		.minorversion = minorversion,
+		.rpcmount = rpcmount,
 	};
 	struct nfs_client *clp;
 	int error;
@@ -1480,6 +1497,7 @@ static int nfs4_init_server(struct nfs_server *server,
 		const struct nfs_parsed_mount_data *data)
 {
 	struct rpc_timeout timeparms;
+	struct vfsmount *rpcmount;
 	int error;
 
 	dprintk("--> nfs4_init_server()\n");
@@ -1494,6 +1512,11 @@ static int nfs4_init_server(struct nfs_server *server,
 			server->caps |= NFS_CAP_READDIRPLUS;
 	server->options = data->options;
 
+	rpcmount = get_rpc_pipefs(data->rpcmount);
+	if (IS_ERR(rpcmount)) {
+		error = PTR_ERR(rpcmount);
+		goto error;
+	}
 	/* Get a client record */
 	error = nfs4_set_client(server,
 			data->nfs_server.hostname,
@@ -1503,7 +1526,9 @@ static int nfs4_init_server(struct nfs_server *server,
 			data->auth_flavors[0],
 			data->nfs_server.protocol,
 			&timeparms,
-			data->minorversion);
+			data->minorversion,
+			rpcmount);
+	mntput(rpcmount);
 	if (error < 0)
 		goto error;
 
@@ -1593,7 +1618,10 @@ struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
 				data->authflavor,
 				parent_server->client->cl_xprt->prot,
 				parent_server->client->cl_timeout,
-				parent_client->cl_mvops->minor_version);
+				parent_client->cl_mvops->minor_version,
+				parent_client->cl_rpcmount);
+
+
 	if (error < 0)
 		goto error;
 
@@ -1667,7 +1695,7 @@ struct nfs_server *nfs_clone_server(struct nfs_server *source,
 		(unsigned long long) server->fsid.major,
 		(unsigned long long) server->fsid.minor);
 
-	error = nfs_start_lockd(server);
+	error = nfs_start_lockd(server, server->nfs_client->cl_rpcmount);
 	if (error < 0)
 		goto out_free_server;
 
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index cf9fdbd..868acb2 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -86,6 +86,7 @@ struct nfs_parsed_mount_data {
 	unsigned int		version;
 	unsigned int		minorversion;
 	char			*fscache_uniq;
+	char			*rpcmount;
 
 	struct {
 		struct sockaddr_storage	address;
@@ -120,6 +121,7 @@ struct nfs_mount_request {
 	int			noresvport;
 	unsigned int		*auth_flav_len;
 	rpc_authflavor_t	*auth_flavs;
+	struct vfsmount		*rpcmount;
 };
 
 extern int nfs_mount(struct nfs_mount_request *info);
@@ -163,10 +165,14 @@ static inline void nfs_fs_proc_exit(void)
 
 /* nfs4namespace.c */
 #ifdef CONFIG_NFS_V4
-extern struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry);
+extern struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent,
+		struct dentry *dentry,
+		struct vfsmount *rpcmount);
 #else
 static inline
-struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry)
+struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent,
+		struct dentry *dentry,
+		struct vfsmount *rpcmount)
 {
 	return ERR_PTR(-ENOENT);
 }
diff --git a/fs/nfs/mount_clnt.c b/fs/nfs/mount_clnt.c
index 6227875..205cc02 100644
--- a/fs/nfs/mount_clnt.c
+++ b/fs/nfs/mount_clnt.c
@@ -13,7 +13,6 @@
 #include <linux/in.h>
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/sched.h>
-#include <linux/sunrpc/rpc_pipe_fs.h>
 #include <linux/nfs_fs.h>
 #include "internal.h"
 
@@ -162,7 +161,7 @@ int nfs_mount(struct nfs_mount_request *info)
 		.program	= &mnt_program,
 		.version	= info->version,
 		.authflavor	= RPC_AUTH_UNIX,
-		.rpcmount	= init_rpc_pipefs,
+		.rpcmount	= info->rpcmount,
 	};
 	struct rpc_clnt		*mnt_clnt;
 	int			status;
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index f32b860..2a2899b 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -143,7 +143,8 @@ struct vfsmount *nfs_d_automount(struct path *path)
 	}
 
 	if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
-		mnt = nfs_do_refmount(path->mnt, path->dentry);
+		mnt = nfs_do_refmount(path->mnt, path->dentry,
+				server->nfs_client->cl_rpcmount);
 	else
 		mnt = nfs_do_submount(path->mnt, path->dentry, fh, fattr);
 	if (IS_ERR(mnt))
diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c
index 7a61fdb..92d5d63 100644
--- a/fs/nfs/nfs4namespace.c
+++ b/fs/nfs/nfs4namespace.c
@@ -14,7 +14,6 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/sunrpc/clnt.h>
-#include <linux/sunrpc/rpc_pipe_fs.h>
 #include <linux/vfs.h>
 #include <linux/inet.h>
 #include "internal.h"
@@ -99,14 +98,13 @@ static int nfs4_validate_fspath(const struct vfsmount *mnt_parent,
 }
 
 static size_t nfs_parse_server_name(char *string, size_t len,
-		struct sockaddr *sa, size_t salen)
+		struct sockaddr *sa, size_t salen, struct vfsmount *rpcmount)
 {
 	ssize_t ret;
 
 	ret = rpc_pton(string, len, sa, salen);
 	if (ret == 0) {
-		ret = nfs_dns_resolve_name(string, len, sa, salen,
-				init_rpc_pipefs);
+		ret = nfs_dns_resolve_name(string, len, sa, salen, rpcmount);
 		if (ret < 0)
 			ret = 0;
 	}
@@ -115,7 +113,8 @@ static size_t nfs_parse_server_name(char *string, size_t len,
 
 static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
 				     char *page, char *page2,
-				     const struct nfs4_fs_location *location)
+				     const struct nfs4_fs_location *location,
+				     struct vfsmount *rpcmount)
 {
 	const size_t addr_bufsize = sizeof(struct sockaddr_storage);
 	struct vfsmount *mnt = ERR_PTR(-ENOENT);
@@ -143,7 +142,7 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
 			continue;
 
 		mountdata->addrlen = nfs_parse_server_name(buf->data, buf->len,
-				mountdata->addr, addr_bufsize);
+				mountdata->addr, addr_bufsize, rpcmount);
 		if (mountdata->addrlen == 0)
 			continue;
 
@@ -174,7 +173,8 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
  */
 static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent,
 					    const struct dentry *dentry,
-					    const struct nfs4_fs_locations *locations)
+					    const struct nfs4_fs_locations *locations,
+					    struct vfsmount *rpcmount)
 {
 	struct vfsmount *mnt = ERR_PTR(-ENOENT);
 	struct nfs_clone_mount mountdata = {
@@ -213,7 +213,7 @@ static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent,
 		    location->rootpath.ncomponents == 0)
 			continue;
 
-		mnt = try_location(&mountdata, page, page2, location);
+		mnt = try_location(&mountdata, page, page2, location, rpcmount);
 		if (!IS_ERR(mnt))
 			break;
 	}
@@ -231,7 +231,9 @@ out:
  * @dentry - dentry of referral
  *
  */
-struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry)
+struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent,
+		struct dentry *dentry,
+		struct vfsmount *rpcmount)
 {
 	struct vfsmount *mnt = ERR_PTR(-ENOMEM);
 	struct dentry *parent;
@@ -264,7 +266,7 @@ struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentr
 	    fs_locations->fs_path.ncomponents <= 0)
 		goto out_free;
 
-	mnt = nfs_follow_referral(mnt_parent, dentry, fs_locations);
+	mnt = nfs_follow_referral(mnt_parent, dentry, fs_locations, rpcmount);
 out_free:
 	__free_page(page);
 	kfree(fs_locations);
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index b68c860..be4852b 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -35,6 +35,7 @@
 #include <linux/sunrpc/metrics.h>
 #include <linux/sunrpc/xprtsock.h>
 #include <linux/sunrpc/xprtrdma.h>
+#include <linux/sunrpc/rpc_pipe_fs.h>
 #include <linux/nfs_fs.h>
 #include <linux/nfs_mount.h>
 #include <linux/nfs4_mount.h>
@@ -106,6 +107,7 @@ enum {
 	Opt_lookupcache,
 	Opt_fscache_uniq,
 	Opt_local_lock,
+	Opt_rpcmount,
 
 	/* Special mount options */
 	Opt_userspace, Opt_deprecated, Opt_sloppy,
@@ -178,6 +180,7 @@ static const match_table_t nfs_mount_option_tokens = {
 	{ Opt_lookupcache, "lookupcache=%s" },
 	{ Opt_fscache_uniq, "fsc=%s" },
 	{ Opt_local_lock, "local_lock=%s" },
+	{ Opt_rpcmount, "rpcmount=%s" },
 
 	{ Opt_err, NULL }
 };
@@ -1486,6 +1489,13 @@ static int nfs_parse_mount_options(char *raw,
 				return 0;
 			};
 			break;
+		case Opt_rpcmount:
+			string = match_strdup(args);
+			if (string == NULL)
+				goto out_nomem;
+			kfree(mnt->rpcmount);
+			mnt->rpcmount = string;
+			break;
 
 		/*
 		 * Special options
@@ -1646,11 +1656,19 @@ static int nfs_try_mount(struct nfs_parsed_mount_data *args,
 	request.salen = args->mount_server.addrlen;
 	nfs_set_port(request.sap, &args->mount_server.port, 0);
 
+	request.rpcmount = get_rpc_pipefs(args->rpcmount);
+	if (IS_ERR(request.rpcmount)) {
+		dfprintk(MOUNT,	"NFS: unable get rpc_pipefs mount point, "
+				"error %ld\n", PTR_ERR(request.rpcmount));
+		return PTR_ERR(request.rpcmount);
+	}
+
 	/*
 	 * Now ask the mount server to map our export path
 	 * to a file handle.
 	 */
 	status = nfs_mount(&request);
+	mntput(request.rpcmount);
 	if (status != 0) {
 		dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
 				request.hostname, status);
@@ -2355,6 +2373,7 @@ out:
 	kfree(data->nfs_server.hostname);
 	kfree(data->mount_server.hostname);
 	kfree(data->fscache_uniq);
+	kfree(data->rpcmount);
 	security_free_mnt_opts(&data->lsm_opts);
 out_free_fh:
 	nfs_free_fhandle(mntfh);
@@ -2962,6 +2981,7 @@ out:
 	kfree(data->nfs_server.export_path);
 	kfree(data->nfs_server.hostname);
 	kfree(data->fscache_uniq);
+	kfree(data->rpcmount);
 out_free_data:
 	kfree(data);
 	dprintk("<-- nfs4_get_sb() = %d%s\n", error,
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index b197563..ad8d913 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -36,6 +36,7 @@ struct nfs_client {
 	struct list_head	cl_share_link;	/* link in global client list */
 	struct list_head	cl_superblocks;	/* List of nfs_server structs */
 
+	struct vfsmount		*cl_rpcmount;	/* rpc_pipefs mount point */
 	struct rpc_clnt *	cl_rpcclient;
 	const struct nfs_rpc_ops *rpc_ops;	/* NFS protocol vector */
 	int			cl_proto;	/* Network transport protocol */
-- 
1.7.4