NLM: Introduce external nlm_host set-up and tear-down functions
We would like to remove the per-lock-operation nlm_lookup_host() call from
nlmclnt_proc().
The new architecture pins an nlm_host structure to each NFS client
superblock that has the "lock" mount option set. The NFS client passes
in the pinned nlm_host structure during each call to nlmclnt_proc(). NFS
client unmount processing "puts" the nlm_host so it can be garbage-
collected later.
This patch introduces externally callable NLM functions that handle
mount-time nlm_host set up and tear-down.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/lockd/clntlock.c b/fs/lockd/clntlock.c
index d070b18..9a8f4f4 100644
--- a/fs/lockd/clntlock.c
+++ b/fs/lockd/clntlock.c
@@ -41,6 +41,54 @@
static LIST_HEAD(nlm_blocked);
+/**
+ * nlmclnt_init - Set up per-NFS mount point lockd data structures
+ * @server_name: server's hostname
+ * @server_address: server's network address
+ * @server_addrlen: length of server's address
+ * @protocol: transport protocol lockd should use
+ * @nfs_version: NFS protocol version for this mount point
+ *
+ * Returns pointer to an appropriate nlm_host struct,
+ * or an ERR_PTR value.
+ */
+struct nlm_host *nlmclnt_init(const char *server_name,
+ const struct sockaddr *server_address,
+ size_t server_addrlen,
+ unsigned short protocol, u32 nfs_version)
+{
+ struct nlm_host *host;
+ u32 nlm_version = (nfs_version == 2) ? 1 : 4;
+ int status;
+
+ status = lockd_up(protocol);
+ if (status < 0)
+ return ERR_PTR(status);
+
+ host = nlmclnt_lookup_host((struct sockaddr_in *)server_address,
+ protocol, nlm_version,
+ server_name, strlen(server_name));
+ if (host == NULL) {
+ lockd_down();
+ return ERR_PTR(-ENOLCK);
+ }
+
+ return host;
+}
+EXPORT_SYMBOL_GPL(nlmclnt_init);
+
+/**
+ * nlmclnt_done - Release resources allocated by nlmclnt_init()
+ * @host: nlm_host structure reserved by nlmclnt_init()
+ *
+ */
+void nlmclnt_done(struct nlm_host *host)
+{
+ nlm_release_host(host);
+ lockd_down();
+}
+EXPORT_SYMBOL_GPL(nlmclnt_done);
+
/*
* Queue up a lock for blocking so that the GRANTED request can see it
*/