linux/fs/afs/server.c

// SPDX-License-Identifier: GPL-2.0-or-later
/* AFS server record management
 *
 * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells ([email protected])
 */

#include <linux/sched.h>
#include <linux/slab.h>
#include "afs_fs.h"
#include "internal.h"
#include "protocol_yfs.h"

static unsigned afs_server_gc_delay = …;	/* Server record timeout in seconds */
static atomic_t afs_server_debug_id;

static struct afs_server *afs_maybe_use_server(struct afs_server *,
					       enum afs_server_trace);
static void __afs_put_server(struct afs_net *, struct afs_server *);

/*
 * Find a server by one of its addresses.
 */
struct afs_server *afs_find_server(struct afs_net *net, const struct rxrpc_peer *peer)
{ … }

/*
 * Look up a server by its UUID and mark it active.
 */
struct afs_server *afs_find_server_by_uuid(struct afs_net *net, const uuid_t *uuid)
{ … }

/*
 * Install a server record in the namespace tree.  If there's a clash, we stick
 * it into a list anchored on whichever afs_server struct is actually in the
 * tree.
 */
static struct afs_server *afs_install_server(struct afs_cell *cell,
					     struct afs_server *candidate)
{ … }

/*
 * Allocate a new server record and mark it active.
 */
static struct afs_server *afs_alloc_server(struct afs_cell *cell,
					   const uuid_t *uuid,
					   struct afs_addr_list *alist)
{ … }

/*
 * Look up an address record for a server
 */
static struct afs_addr_list *afs_vl_lookup_addrs(struct afs_cell *cell,
						 struct key *key, const uuid_t *uuid)
{ … }

/*
 * Get or create a fileserver record.
 */
struct afs_server *afs_lookup_server(struct afs_cell *cell, struct key *key,
				     const uuid_t *uuid, u32 addr_version)
{ … }

/*
 * Set the server timer to fire after a given delay, assuming it's not already
 * set for an earlier time.
 */
static void afs_set_server_timer(struct afs_net *net, time64_t delay)
{ … }

/*
 * Server management timer.  We have an increment on fs_outstanding that we
 * need to pass along to the work item.
 */
void afs_servers_timer(struct timer_list *timer)
{ … }

/*
 * Get a reference on a server object.
 */
struct afs_server *afs_get_server(struct afs_server *server,
				  enum afs_server_trace reason)
{ … }

/*
 * Try to get a reference on a server object.
 */
static struct afs_server *afs_maybe_use_server(struct afs_server *server,
					       enum afs_server_trace reason)
{ … }

/*
 * Get an active count on a server object.
 */
struct afs_server *afs_use_server(struct afs_server *server, enum afs_server_trace reason)
{ … }

/*
 * Release a reference on a server record.
 */
void afs_put_server(struct afs_net *net, struct afs_server *server,
		    enum afs_server_trace reason)
{ … }

/*
 * Drop an active count on a server object without updating the last-unused
 * time.
 */
void afs_unuse_server_notime(struct afs_net *net, struct afs_server *server,
			     enum afs_server_trace reason)
{ … }

/*
 * Drop an active count on a server object.
 */
void afs_unuse_server(struct afs_net *net, struct afs_server *server,
		      enum afs_server_trace reason)
{ … }

static void afs_server_rcu(struct rcu_head *rcu)
{ … }

static void __afs_put_server(struct afs_net *net, struct afs_server *server)
{ … }

static void afs_give_up_callbacks(struct afs_net *net, struct afs_server *server)
{ … }

/*
 * destroy a dead server
 */
static void afs_destroy_server(struct afs_net *net, struct afs_server *server)
{ … }

/*
 * Garbage collect any expired servers.
 */
static void afs_gc_servers(struct afs_net *net, struct afs_server *gc_list)
{ … }

/*
 * Manage the records of servers known to be within a network namespace.  This
 * includes garbage collecting unused servers.
 *
 * Note also that we were given an increment on net->servers_outstanding by
 * whoever queued us that we need to deal with before returning.
 */
void afs_manage_servers(struct work_struct *work)
{ … }

static void afs_queue_server_manager(struct afs_net *net)
{ … }

/*
 * Purge list of servers.
 */
void afs_purge_servers(struct afs_net *net)
{ … }

/*
 * Get an update for a server's address list.
 */
static noinline bool afs_update_server_record(struct afs_operation *op,
					      struct afs_server *server,
					      struct key *key)
{ … }

/*
 * See if a server's address list needs updating.
 */
bool afs_check_server_record(struct afs_operation *op, struct afs_server *server,
			     struct key *key)
{ … }