NFS: Add version registering framework
This patch adds in the code to track multiple versions of the NFS
protocol. I created default structures for v2, v3 and v4 so that each
version can continue to work while I convert them into kernel modules.
I also removed the const parameter from the rpc_version array so that I
can change it at runtime.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 65afa38..462de24 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -51,25 +51,23 @@
#include "internal.h"
#include "fscache.h"
#include "pnfs.h"
+#include "nfs.h"
#include "netns.h"
#define NFSDBG_FACILITY NFSDBG_CLIENT
static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
+static DEFINE_SPINLOCK(nfs_version_lock);
+static DEFINE_MUTEX(nfs_version_mutex);
+static LIST_HEAD(nfs_versions);
/*
* RPC cruft for NFS
*/
static const struct rpc_version *nfs_version[5] = {
-#ifdef CONFIG_NFS_V2
- [2] = &nfs_version2,
-#endif
-#ifdef CONFIG_NFS_V3
- [3] = &nfs_version3,
-#endif
-#ifdef CONFIG_NFS_V4
- [4] = &nfs_version4,
-#endif
+ [2] = NULL,
+ [3] = NULL,
+ [4] = NULL,
};
const struct rpc_program nfs_program = {
@@ -101,6 +99,93 @@
};
#endif /* CONFIG_NFS_V3_ACL */
+static struct nfs_subversion *find_nfs_version(unsigned int version)
+{
+ struct nfs_subversion *nfs;
+ spin_lock(&nfs_version_lock);
+
+ list_for_each_entry(nfs, &nfs_versions, list) {
+ if (nfs->rpc_ops->version == version) {
+ spin_unlock(&nfs_version_lock);
+ return nfs;
+ }
+ };
+
+ spin_unlock(&nfs_version_lock);
+ return ERR_PTR(-EPROTONOSUPPORT);;
+}
+
+struct nfs_subversion *get_nfs_version(unsigned int version)
+{
+ struct nfs_subversion *nfs = find_nfs_version(version);
+
+ if (IS_ERR(nfs)) {
+ mutex_lock(&nfs_version_mutex);
+ request_module("nfs%d", version);
+ nfs = find_nfs_version(version);
+ mutex_unlock(&nfs_version_mutex);
+ }
+
+ if (!IS_ERR(nfs))
+ try_module_get(nfs->owner);
+ return nfs;
+}
+
+void put_nfs_version(struct nfs_subversion *nfs)
+{
+ module_put(nfs->owner);
+}
+
+void register_nfs_version(struct nfs_subversion *nfs)
+{
+ spin_lock(&nfs_version_lock);
+
+ list_add(&nfs->list, &nfs_versions);
+ nfs_version[nfs->rpc_ops->version] = nfs->rpc_vers;
+
+ spin_unlock(&nfs_version_lock);
+}
+EXPORT_SYMBOL_GPL(register_nfs_version);
+
+void unregister_nfs_version(struct nfs_subversion *nfs)
+{
+ spin_lock(&nfs_version_lock);
+
+ nfs_version[nfs->rpc_ops->version] = NULL;
+ list_del(&nfs->list);
+
+ spin_unlock(&nfs_version_lock);
+}
+EXPORT_SYMBOL_GPL(unregister_nfs_version);
+
+/*
+ * Preload all configured NFS versions during module init.
+ * This function should be edited after each protocol is converted,
+ * and eventually removed.
+ */
+int __init nfs_register_versions(void)
+{
+ int err = init_nfs_v2();
+ if (err)
+ return err;
+
+ err = init_nfs_v3();
+ if (err)
+ return err;
+
+ return init_nfs_v4();
+}
+
+/*
+ * Remove each pre-loaded NFS version
+ */
+void nfs_unregister_versions(void)
+{
+ exit_nfs_v2();
+ exit_nfs_v3();
+ exit_nfs_v4();
+}
+
/*
* Allocate a shared client record
*
@@ -116,7 +201,10 @@
if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
goto error_0;
- clp->rpc_ops = cl_init->rpc_ops;
+ clp->cl_nfs_mod = cl_init->nfs_mod;
+ try_module_get(clp->cl_nfs_mod->owner);
+
+ clp->rpc_ops = clp->cl_nfs_mod->rpc_ops;
atomic_set(&clp->cl_count, 1);
clp->cl_cons_state = NFS_CS_INITING;
@@ -145,6 +233,7 @@
return clp;
error_cleanup:
+ put_nfs_version(clp->cl_nfs_mod);
kfree(clp);
error_0:
return ERR_PTR(err);
@@ -205,6 +294,7 @@
put_rpccred(clp->cl_machine_cred);
put_net(clp->cl_net);
+ put_nfs_version(clp->cl_nfs_mod);
kfree(clp->cl_hostname);
kfree(clp);
@@ -362,7 +452,7 @@
continue;
/* Different NFS versions cannot share the same nfs_client */
- if (clp->rpc_ops != data->rpc_ops)
+ if (clp->rpc_ops != data->nfs_mod->rpc_ops)
continue;
if (clp->cl_proto != data->proto)
@@ -431,9 +521,10 @@
{
struct nfs_client *clp, *new = NULL;
struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
+ const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
dprintk("--> nfs_get_client(%s,v%u)\n",
- cl_init->hostname ?: "", cl_init->rpc_ops->version);
+ cl_init->hostname ?: "", rpc_ops->version);
/* see if the client already exists */
do {
@@ -450,14 +541,13 @@
list_add(&new->cl_share_link, &nn->nfs_client_list);
spin_unlock(&nn->nfs_client_lock);
new->cl_flags = cl_init->init_flags;
- return cl_init->rpc_ops->init_client(new,
- timeparms, ip_addr,
- authflavour);
+ return rpc_ops->init_client(new, timeparms, ip_addr,
+ authflavour);
}
spin_unlock(&nn->nfs_client_lock);
- new = cl_init->rpc_ops->alloc_client(cl_init);
+ new = rpc_ops->alloc_client(cl_init);
} while (!IS_ERR(new));
dprintk("<-- nfs_get_client() Failed to find %s (%ld)\n",
@@ -714,13 +804,14 @@
* Create a version 2 or 3 client
*/
static int nfs_init_server(struct nfs_server *server,
- const struct nfs_parsed_mount_data *data)
+ const struct nfs_parsed_mount_data *data,
+ struct nfs_subversion *nfs_mod)
{
struct nfs_client_initdata cl_init = {
.hostname = data->nfs_server.hostname,
.addr = (const struct sockaddr *)&data->nfs_server.address,
.addrlen = data->nfs_server.addrlen,
- .rpc_ops = NULL,
+ .nfs_mod = nfs_mod,
.proto = data->nfs_server.protocol,
.net = data->net,
};
@@ -730,21 +821,6 @@
dprintk("--> nfs_init_server()\n");
- switch (data->version) {
-#ifdef CONFIG_NFS_V2
- case 2:
- cl_init.rpc_ops = &nfs_v2_clientops;
- break;
-#endif
-#ifdef CONFIG_NFS_V3
- case 3:
- cl_init.rpc_ops = &nfs_v3_clientops;
- break;
-#endif
- default:
- return -EPROTONOSUPPORT;
- }
-
nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
data->timeo, data->retrans);
if (data->flags & NFS_MOUNT_NORESVPORT)
@@ -1033,7 +1109,8 @@
* - keyed on server and FSID
*/
struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
- struct nfs_fh *mntfh)
+ struct nfs_fh *mntfh,
+ struct nfs_subversion *nfs_mod)
{
struct nfs_server *server;
struct nfs_fattr *fattr;
@@ -1049,7 +1126,7 @@
goto error;
/* Get a client representation */
- error = nfs_init_server(server, data);
+ error = nfs_init_server(server, data, nfs_mod);
if (error < 0)
goto error;