linux/fs/lockd/clntlock.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * linux/fs/lockd/clntlock.c
 *
 * Lock handling for the client side NLM implementation
 *
 * Copyright (C) 1996, Olaf Kirch <[email protected]>
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/nfs_fs.h>
#include <linux/sunrpc/addr.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/svc_xprt.h>
#include <linux/lockd/lockd.h>
#include <linux/kthread.h>

#include "trace.h"

#define NLMDBG_FACILITY …

/*
 * Local function prototypes
 */
static int			reclaimer(void *ptr);

/*
 * The following functions handle blocking and granting from the
 * client perspective.
 */

static LIST_HEAD(nlm_blocked);
static DEFINE_SPINLOCK(nlm_blocked_lock);

/**
 * nlmclnt_init - Set up per-NFS mount point lockd data structures
 * @nlm_init: pointer to arguments structure
 *
 * Returns pointer to an appropriate nlm_host struct,
 * or an ERR_PTR value.
 */
struct nlm_host *nlmclnt_init(const struct nlmclnt_initdata *nlm_init)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * nlmclnt_done - Release resources allocated by nlmclnt_init()
 * @host: nlm_host structure reserved by nlmclnt_init()
 *
 */
void nlmclnt_done(struct nlm_host *host)
{ … }
EXPORT_SYMBOL_GPL(…);

void nlmclnt_prepare_block(struct nlm_wait *block, struct nlm_host *host, struct file_lock *fl)
{ … }

struct rpc_clnt *nlmclnt_rpc_clnt(struct nlm_host *host)
{ … }
EXPORT_SYMBOL_GPL(…);

/*
 * Queue up a lock for blocking so that the GRANTED request can see it
 */
void nlmclnt_queue_block(struct nlm_wait *block)
{ … }

/*
 * Dequeue the block and return its final status
 */
__be32 nlmclnt_dequeue_block(struct nlm_wait *block)
{ … }

/*
 * Block on a lock
 */
int nlmclnt_wait(struct nlm_wait *block, struct nlm_rqst *req, long timeout)
{ … }

/*
 * The server lockd has called us back to tell us the lock was granted
 */
__be32 nlmclnt_grant(const struct sockaddr *addr, const struct nlm_lock *lock)
{ … }

/*
 * The following procedures deal with the recovery of locks after a
 * server crash.
 */

/*
 * Reclaim all locks on server host. We do this by spawning a separate
 * reclaimer thread.
 */
void
nlmclnt_recovery(struct nlm_host *host)
{ … }

static int
reclaimer(void *ptr)
{ … }