linux-stable/drivers/s390/crypto/zcrypt_cex2a.c
Harald Freudenberger 104f708fd1 s390/zcrypt: reinit ap queue state machine during device probe
Until the vfio-ap driver came into live there was a well known
agreement about the way how ap devices are initialized and their
states when the driver's probe function is called.

However, the vfio device driver when receiving an ap queue device does
additional resets thereby removing the registration for interrupts for
the ap device done by the ap bus core code. So when later the vfio
driver releases the device and one of the default zcrypt drivers takes
care of the device the interrupt registration needs to get
renewed. The current code does no renew and result is that requests
send into such a queue will never see a reply processed - the
application hangs.

This patch adds a function which resets the aq queue state machine for
the ap queue device and triggers the walk through the initial states
(which are reset and registration for interrupts). This function is
now called before the driver's probe function is invoked.

When the association between driver and device is released, the
driver's remove function is called. The current implementation calls a
ap queue function ap_queue_remove(). This invokation has been moved to
the ap bus function to make the probe / remove pair for ap bus and
drivers more symmetric.

Fixes: 7e0bdbe5c2 ("s390/zcrypt: AP bus support for alternate driver(s)")
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewd-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewd-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-11-27 10:43:35 +01:00

236 lines
6.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright IBM Corp. 2001, 2012
* Author(s): Robert Burroughs
* Eric Rossman (edrossma@us.ibm.com)
*
* Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
* Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
* Ralph Wuerthner <rwuerthn@de.ibm.com>
* MSGTYPE restruct: Holger Dengler <hd@linux.vnet.ibm.com>
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/atomic.h>
#include <linux/uaccess.h>
#include <linux/mod_devicetable.h>
#include "ap_bus.h"
#include "zcrypt_api.h"
#include "zcrypt_error.h"
#include "zcrypt_cex2a.h"
#include "zcrypt_msgtype50.h"
#define CEX2A_MIN_MOD_SIZE 1 /* 8 bits */
#define CEX2A_MAX_MOD_SIZE 256 /* 2048 bits */
#define CEX3A_MIN_MOD_SIZE CEX2A_MIN_MOD_SIZE
#define CEX3A_MAX_MOD_SIZE 512 /* 4096 bits */
#define CEX2A_MAX_MESSAGE_SIZE 0x390 /* sizeof(struct type50_crb2_msg) */
#define CEX2A_MAX_RESPONSE_SIZE 0x110 /* max outputdatalength + type80_hdr */
#define CEX3A_MAX_RESPONSE_SIZE 0x210 /* 512 bit modulus
* (max outputdatalength) +
* type80_hdr*/
#define CEX3A_MAX_MESSAGE_SIZE sizeof(struct type50_crb3_msg)
#define CEX2A_CLEANUP_TIME (15*HZ)
#define CEX3A_CLEANUP_TIME CEX2A_CLEANUP_TIME
MODULE_AUTHOR("IBM Corporation");
MODULE_DESCRIPTION("CEX2A/CEX3A Cryptographic Coprocessor device driver, " \
"Copyright IBM Corp. 2001, 2018");
MODULE_LICENSE("GPL");
static struct ap_device_id zcrypt_cex2a_card_ids[] = {
{ .dev_type = AP_DEVICE_TYPE_CEX2A,
.match_flags = AP_DEVICE_ID_MATCH_CARD_TYPE },
{ .dev_type = AP_DEVICE_TYPE_CEX3A,
.match_flags = AP_DEVICE_ID_MATCH_CARD_TYPE },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_card_ids);
static struct ap_device_id zcrypt_cex2a_queue_ids[] = {
{ .dev_type = AP_DEVICE_TYPE_CEX2A,
.match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
{ .dev_type = AP_DEVICE_TYPE_CEX3A,
.match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_queue_ids);
/**
* Probe function for CEX2A card devices. It always accepts the AP device
* since the bus_match already checked the card type.
* @ap_dev: pointer to the AP device.
*/
static int zcrypt_cex2a_card_probe(struct ap_device *ap_dev)
{
/*
* Normalized speed ratings per crypto adapter
* MEX_1k, MEX_2k, MEX_4k, CRT_1k, CRT_2k, CRT_4k, RNG, SECKEY
*/
static const int CEX2A_SPEED_IDX[] = {
800, 1000, 2000, 900, 1200, 2400, 0, 0};
static const int CEX3A_SPEED_IDX[] = {
400, 500, 1000, 450, 550, 1200, 0, 0};
struct ap_card *ac = to_ap_card(&ap_dev->device);
struct zcrypt_card *zc;
int rc = 0;
zc = zcrypt_card_alloc();
if (!zc)
return -ENOMEM;
zc->card = ac;
ac->private = zc;
if (ac->ap_dev.device_type == AP_DEVICE_TYPE_CEX2A) {
zc->min_mod_size = CEX2A_MIN_MOD_SIZE;
zc->max_mod_size = CEX2A_MAX_MOD_SIZE;
memcpy(zc->speed_rating, CEX2A_SPEED_IDX,
sizeof(CEX2A_SPEED_IDX));
zc->max_exp_bit_length = CEX2A_MAX_MOD_SIZE;
zc->type_string = "CEX2A";
zc->user_space_type = ZCRYPT_CEX2A;
} else if (ac->ap_dev.device_type == AP_DEVICE_TYPE_CEX3A) {
zc->min_mod_size = CEX2A_MIN_MOD_SIZE;
zc->max_mod_size = CEX2A_MAX_MOD_SIZE;
zc->max_exp_bit_length = CEX2A_MAX_MOD_SIZE;
if (ap_test_bit(&ac->functions, AP_FUNC_MEX4K) &&
ap_test_bit(&ac->functions, AP_FUNC_CRT4K)) {
zc->max_mod_size = CEX3A_MAX_MOD_SIZE;
zc->max_exp_bit_length = CEX3A_MAX_MOD_SIZE;
}
memcpy(zc->speed_rating, CEX3A_SPEED_IDX,
sizeof(CEX3A_SPEED_IDX));
zc->type_string = "CEX3A";
zc->user_space_type = ZCRYPT_CEX3A;
} else {
zcrypt_card_free(zc);
return -ENODEV;
}
zc->online = 1;
rc = zcrypt_card_register(zc);
if (rc) {
ac->private = NULL;
zcrypt_card_free(zc);
}
return rc;
}
/**
* This is called to remove the CEX2A card driver information
* if an AP card device is removed.
*/
static void zcrypt_cex2a_card_remove(struct ap_device *ap_dev)
{
struct zcrypt_card *zc = to_ap_card(&ap_dev->device)->private;
if (zc)
zcrypt_card_unregister(zc);
}
static struct ap_driver zcrypt_cex2a_card_driver = {
.probe = zcrypt_cex2a_card_probe,
.remove = zcrypt_cex2a_card_remove,
.ids = zcrypt_cex2a_card_ids,
.flags = AP_DRIVER_FLAG_DEFAULT,
};
/**
* Probe function for CEX2A queue devices. It always accepts the AP device
* since the bus_match already checked the queue type.
* @ap_dev: pointer to the AP device.
*/
static int zcrypt_cex2a_queue_probe(struct ap_device *ap_dev)
{
struct ap_queue *aq = to_ap_queue(&ap_dev->device);
struct zcrypt_queue *zq = NULL;
int rc;
switch (ap_dev->device_type) {
case AP_DEVICE_TYPE_CEX2A:
zq = zcrypt_queue_alloc(CEX2A_MAX_RESPONSE_SIZE);
if (!zq)
return -ENOMEM;
break;
case AP_DEVICE_TYPE_CEX3A:
zq = zcrypt_queue_alloc(CEX3A_MAX_RESPONSE_SIZE);
if (!zq)
return -ENOMEM;
break;
}
if (!zq)
return -ENODEV;
zq->ops = zcrypt_msgtype(MSGTYPE50_NAME, MSGTYPE50_VARIANT_DEFAULT);
zq->queue = aq;
zq->online = 1;
atomic_set(&zq->load, 0);
ap_queue_init_reply(aq, &zq->reply);
aq->request_timeout = CEX2A_CLEANUP_TIME,
aq->private = zq;
rc = zcrypt_queue_register(zq);
if (rc) {
aq->private = NULL;
zcrypt_queue_free(zq);
}
return rc;
}
/**
* This is called to remove the CEX2A queue driver information
* if an AP queue device is removed.
*/
static void zcrypt_cex2a_queue_remove(struct ap_device *ap_dev)
{
struct ap_queue *aq = to_ap_queue(&ap_dev->device);
struct zcrypt_queue *zq = aq->private;
if (zq)
zcrypt_queue_unregister(zq);
}
static struct ap_driver zcrypt_cex2a_queue_driver = {
.probe = zcrypt_cex2a_queue_probe,
.remove = zcrypt_cex2a_queue_remove,
.suspend = ap_queue_suspend,
.resume = ap_queue_resume,
.ids = zcrypt_cex2a_queue_ids,
.flags = AP_DRIVER_FLAG_DEFAULT,
};
int __init zcrypt_cex2a_init(void)
{
int rc;
rc = ap_driver_register(&zcrypt_cex2a_card_driver,
THIS_MODULE, "cex2acard");
if (rc)
return rc;
rc = ap_driver_register(&zcrypt_cex2a_queue_driver,
THIS_MODULE, "cex2aqueue");
if (rc)
ap_driver_unregister(&zcrypt_cex2a_card_driver);
return rc;
}
void __exit zcrypt_cex2a_exit(void)
{
ap_driver_unregister(&zcrypt_cex2a_queue_driver);
ap_driver_unregister(&zcrypt_cex2a_card_driver);
}
module_init(zcrypt_cex2a_init);
module_exit(zcrypt_cex2a_exit);