/*
* Copyright (C) 2003 Sistina Software Limited.
* Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
*
* This file is released under the GPL.
*/
#include "dm.h"
#include "dm-path-selector.h"
#include "dm-hw-handler.h"
#include "dm-bio-list.h"
#include "dm-bio-record.h"
#include "dm-uevent.h"
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/mempool.h>
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/workqueue.h>
#include <asm/atomic.h>
#define DM_MSG_PREFIX "multipath"
#define MESG_STR(x) x, sizeof(x)
/* Path properties */
struct pgpath {
struct list_head list;
struct priority_group *pg; /* Owning PG */
unsigned fail_count; /* Cumulative failure count */
struct dm_path path;
};
#define path_to_pgpath(__pgp) container_of((__pgp), struct pgpath, path)
/*
* Paths are grouped into Priority Groups and numbered from 1 upwards.
* Each has a path selector which controls which path gets used.
*/
struct priority_group {
struct list_head list;
struct multipath *m; /* Owning multipath instance */
struct path_selector ps;
unsigned pg_num; /* Reference number */
unsigned bypassed; /* Temporarily bypass this PG? */
unsigned nr_pgpaths; /* Number of paths in PG */
struct list_head pgpaths;
};
/* Multipath context */
struct multipath {
struct list_head list;
struct dm_target *ti;
spinlock_t lock;
struct hw_handler hw_handler;
unsigned nr_priority_groups;
struct list_head priority_groups;
unsigned pg_init_required; /* pg_init needs calling? */
