Commit 52c4044d authored by Chuck Lever's avatar Chuck Lever Committed by Trond Myklebust
Browse files

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: default avatarChuck Lever <chuck.lever@oracle.com>
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 86d61d86

fs/lockd/clntlock.c

+48 −0
Original line number Diff line number Diff line
@@ -41,6 +41,54 @@ struct nlm_wait { 


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

 */

include/linux/lockd/bind.h

+7 −0
Original line number Diff line number Diff line
@@ -35,6 +35,13 @@ extern struct nlmsvc_binding * nlmsvc_ops; 
/*

 * Functions exported by the lockd module

 */

extern struct nlm_host *nlmclnt_init(const char *server_name,

					const struct sockaddr *server_address,

					size_t server_addrlen,

					unsigned short protocol,

					u32 nfs_version);

extern void	nlmclnt_done(struct nlm_host *host);



extern int	nlmclnt_proc(struct inode *, int, struct file_lock *);

extern int	lockd_up(int proto);

extern void	lockd_down(void);

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