linux/drivers/s390/cio/css.h
Cornelia Huck 22806dc1a8 [S390] cio: Fix race for "fast" path gone/path back situations.
Make sure we wait for previous evaluations triggered by path state
changes to have settled before we manipulate path states again.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:46:57 +02:00

151 lines
4.2 KiB
C

#ifndef _CSS_H
#define _CSS_H
#include <linux/mutex.h>
#include <linux/wait.h>
#include <linux/workqueue.h>
#include <linux/device.h>
#include <linux/types.h>
#include <asm/cio.h>
#include <asm/chpid.h>
#include "schid.h"
/*
* path grouping stuff
*/
#define SPID_FUNC_SINGLE_PATH 0x00
#define SPID_FUNC_MULTI_PATH 0x80
#define SPID_FUNC_ESTABLISH 0x00
#define SPID_FUNC_RESIGN 0x40
#define SPID_FUNC_DISBAND 0x20
#define SNID_STATE1_RESET 0
#define SNID_STATE1_UNGROUPED 2
#define SNID_STATE1_GROUPED 3
#define SNID_STATE2_NOT_RESVD 0
#define SNID_STATE2_RESVD_ELSE 2
#define SNID_STATE2_RESVD_SELF 3
#define SNID_STATE3_MULTI_PATH 1
#define SNID_STATE3_SINGLE_PATH 0
struct path_state {
__u8 state1 : 2; /* path state value 1 */
__u8 state2 : 2; /* path state value 2 */
__u8 state3 : 1; /* path state value 3 */
__u8 resvd : 3; /* reserved */
} __attribute__ ((packed));
struct extended_cssid {
u8 version;
u8 cssid;
} __attribute__ ((packed));
struct pgid {
union {
__u8 fc; /* SPID function code */
struct path_state ps; /* SNID path state */
} __attribute__ ((packed)) inf;
union {
__u32 cpu_addr : 16; /* CPU address */
struct extended_cssid ext_cssid;
} __attribute__ ((packed)) pgid_high;
__u32 cpu_id : 24; /* CPU identification */
__u32 cpu_model : 16; /* CPU model */
__u32 tod_high; /* high word TOD clock */
} __attribute__ ((packed));
/*
* A css driver handles all subchannels of one type.
* Currently, we only care about I/O subchannels (type 0), these
* have a ccw_device connected to them.
*/
struct subchannel;
struct css_driver {
struct module *owner;
unsigned int subchannel_type;
struct device_driver drv;
void (*irq)(struct subchannel *);
int (*notify)(struct subchannel *, int);
void (*verify)(struct subchannel *);
void (*termination)(struct subchannel *);
int (*probe)(struct subchannel *);
int (*remove)(struct subchannel *);
void (*shutdown)(struct subchannel *);
const char *name;
};
#define to_cssdriver(n) container_of(n, struct css_driver, drv)
/*
* all css_drivers have the css_bus_type
*/
extern struct bus_type css_bus_type;
extern int css_driver_register(struct css_driver *);
extern void css_driver_unregister(struct css_driver *);
extern void css_sch_device_unregister(struct subchannel *);
extern struct subchannel * get_subchannel_by_schid(struct subchannel_id);
extern int css_init_done;
int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
int (*fn_unknown)(struct subchannel_id,
void *), void *data);
extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
extern void css_process_crw(int, int);
extern void css_reiterate_subchannels(void);
void css_update_ssd_info(struct subchannel *sch);
#define __MAX_SUBCHANNEL 65535
#define __MAX_SSID 3
struct channel_subsystem {
u8 cssid;
int valid;
struct channel_path *chps[__MAX_CHPID + 1];
struct device device;
struct pgid global_pgid;
struct mutex mutex;
/* channel measurement related */
int cm_enabled;
void *cub_addr1;
void *cub_addr2;
/* for orphaned ccw devices */
struct subchannel *pseudo_subchannel;
};
#define to_css(dev) container_of(dev, struct channel_subsystem, device)
extern struct bus_type css_bus_type;
extern struct channel_subsystem *channel_subsystems[];
/* Some helper functions for disconnected state. */
int device_is_disconnected(struct subchannel *);
void device_set_disconnected(struct subchannel *);
void device_trigger_reprobe(struct subchannel *);
/* Helper functions for vary on/off. */
int device_is_online(struct subchannel *);
void device_kill_io(struct subchannel *);
void device_set_intretry(struct subchannel *sch);
int device_trigger_verify(struct subchannel *sch);
/* Machine check helper function. */
void device_kill_pending_timer(struct subchannel *);
/* Helper functions to build lists for the slow path. */
void css_schedule_eval(struct subchannel_id schid);
void css_schedule_eval_all(void);
int sch_is_pseudo_sch(struct subchannel *);
struct schib;
int css_sch_is_valid(struct schib *);
extern struct workqueue_struct *slow_path_wq;
void css_wait_for_slow_path(void);
extern struct attribute_group *subch_attr_groups[];
#endif