kernel-fxtec-pro1x/drivers/s390/crypto/ap_bus.h
Ralph Wuerthner af512ed0f8 [S390] zcrypt: fix request timeout handling
Under very high load zcrypt requests may timeout while waiting on the
request queue. Modify zcrypt that timeouts are based on crypto adapter
responses. A timeout occurs only if a crypto adapter does not respond
within a given time frame to sumitted requests.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-07-10 11:24:52 +02:00

170 lines
5.4 KiB
C

/*
* linux/drivers/s390/crypto/ap_bus.h
*
* Copyright (C) 2006 IBM Corporation
* Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
* Ralph Wuerthner <rwuerthn@de.ibm.com>
*
* Adjunct processor bus header file.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef _AP_BUS_H_
#define _AP_BUS_H_
#include <linux/device.h>
#include <linux/mod_devicetable.h>
#include <linux/types.h>
#define AP_DEVICES 64 /* Number of AP devices. */
#define AP_DOMAINS 16 /* Number of AP domains. */
#define AP_MAX_RESET 90 /* Maximum number of resets. */
#define AP_RESET_TIMEOUT (HZ/2) /* Time in ticks for reset timeouts. */
#define AP_CONFIG_TIME 30 /* Time in seconds between AP bus rescans. */
#define AP_POLL_TIME 1 /* Time in ticks between receive polls. */
extern int ap_domain_index;
/**
* The ap_qid_t identifier of an ap queue. It contains a
* 6 bit device index and a 4 bit queue index (domain).
*/
typedef unsigned int ap_qid_t;
#define AP_MKQID(_device,_queue) (((_device) & 63) << 8 | ((_queue) & 15))
#define AP_QID_DEVICE(_qid) (((_qid) >> 8) & 63)
#define AP_QID_QUEUE(_qid) ((_qid) & 15)
/**
* The ap queue status word is returned by all three AP functions
* (PQAP, NQAP and DQAP). There's a set of flags in the first
* byte, followed by a 1 byte response code.
*/
struct ap_queue_status {
unsigned int queue_empty : 1;
unsigned int replies_waiting : 1;
unsigned int queue_full : 1;
unsigned int pad1 : 5;
unsigned int response_code : 8;
unsigned int pad2 : 16;
};
#define AP_RESPONSE_NORMAL 0x00
#define AP_RESPONSE_Q_NOT_AVAIL 0x01
#define AP_RESPONSE_RESET_IN_PROGRESS 0x02
#define AP_RESPONSE_DECONFIGURED 0x03
#define AP_RESPONSE_CHECKSTOPPED 0x04
#define AP_RESPONSE_BUSY 0x05
#define AP_RESPONSE_Q_FULL 0x10
#define AP_RESPONSE_NO_PENDING_REPLY 0x10
#define AP_RESPONSE_INDEX_TOO_BIG 0x11
#define AP_RESPONSE_NO_FIRST_PART 0x13
#define AP_RESPONSE_MESSAGE_TOO_BIG 0x15
/**
* Known device types
*/
#define AP_DEVICE_TYPE_PCICC 3
#define AP_DEVICE_TYPE_PCICA 4
#define AP_DEVICE_TYPE_PCIXCC 5
#define AP_DEVICE_TYPE_CEX2A 6
#define AP_DEVICE_TYPE_CEX2C 7
/**
* AP reset flag states
*/
#define AP_RESET_IGNORE 0 /* request timeout will be ignored */
#define AP_RESET_ARMED 1 /* request timeout timer is active */
#define AP_RESET_DO 2 /* AP reset required */
struct ap_device;
struct ap_message;
struct ap_driver {
struct device_driver driver;
struct ap_device_id *ids;
int (*probe)(struct ap_device *);
void (*remove)(struct ap_device *);
/* receive is called from tasklet context */
void (*receive)(struct ap_device *, struct ap_message *,
struct ap_message *);
int request_timeout; /* request timeout in jiffies */
};
#define to_ap_drv(x) container_of((x), struct ap_driver, driver)
int ap_driver_register(struct ap_driver *, struct module *, char *);
void ap_driver_unregister(struct ap_driver *);
struct ap_device {
struct device device;
struct ap_driver *drv; /* Pointer to AP device driver. */
spinlock_t lock; /* Per device lock. */
struct list_head list; /* private list of all AP devices. */
ap_qid_t qid; /* AP queue id. */
int queue_depth; /* AP queue depth.*/
int device_type; /* AP device type. */
int unregistered; /* marks AP device as unregistered */
struct timer_list timeout; /* Timer for request timeouts. */
int reset; /* Reset required after req. timeout. */
int queue_count; /* # messages currently on AP queue. */
struct list_head pendingq; /* List of message sent to AP queue. */
int pendingq_count; /* # requests on pendingq list. */
struct list_head requestq; /* List of message yet to be sent. */
int requestq_count; /* # requests on requestq list. */
int total_request_count; /* # requests ever for this AP device. */
struct ap_message *reply; /* Per device reply message. */
void *private; /* ap driver private pointer. */
};
#define to_ap_dev(x) container_of((x), struct ap_device, device)
struct ap_message {
struct list_head list; /* Request queueing. */
unsigned long long psmid; /* Message id. */
void *message; /* Pointer to message buffer. */
size_t length; /* Message length. */
void *private; /* ap driver private pointer. */
};
#define AP_DEVICE(dt) \
.dev_type=(dt), \
.match_flags=AP_DEVICE_ID_MATCH_DEVICE_TYPE,
/**
* Note: don't use ap_send/ap_recv after using ap_queue_message
* for the first time. Otherwise the ap message queue will get
* confused.
*/
int ap_send(ap_qid_t, unsigned long long, void *, size_t);
int ap_recv(ap_qid_t, unsigned long long *, void *, size_t);
void ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg);
void ap_cancel_message(struct ap_device *ap_dev, struct ap_message *ap_msg);
void ap_flush_queue(struct ap_device *ap_dev);
int ap_module_init(void);
void ap_module_exit(void);
#endif /* _AP_BUS_H_ */