linux-stable/drivers/s390/crypto/zcrypt_pcixcc.c
Harald Freudenberger e432a58d7a s390/zcrypt: reinit ap queue state machine during device probe
[ Upstream commit 104f708fd1 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-16 08:21:57 +02:00

316 lines
8.2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* zcrypt 2.1.0
*
* 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/init.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/slab.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_msgtype6.h"
#include "zcrypt_pcixcc.h"
#include "zcrypt_cca_key.h"
#define PCIXCC_MIN_MOD_SIZE 16 /* 128 bits */
#define PCIXCC_MIN_MOD_SIZE_OLD 64 /* 512 bits */
#define PCIXCC_MAX_MOD_SIZE 256 /* 2048 bits */
#define CEX3C_MIN_MOD_SIZE PCIXCC_MIN_MOD_SIZE
#define CEX3C_MAX_MOD_SIZE 512 /* 4096 bits */
#define PCIXCC_MAX_ICA_MESSAGE_SIZE 0x77c /* max size type6 v2 crt message */
#define PCIXCC_MAX_ICA_RESPONSE_SIZE 0x77c /* max size type86 v2 reply */
#define PCIXCC_MAX_XCRB_MESSAGE_SIZE (12*1024)
#define PCIXCC_CLEANUP_TIME (15*HZ)
#define CEIL4(x) ((((x)+3)/4)*4)
struct response_type {
struct completion work;
int type;
};
#define PCIXCC_RESPONSE_TYPE_ICA 0
#define PCIXCC_RESPONSE_TYPE_XCRB 1
MODULE_AUTHOR("IBM Corporation");
MODULE_DESCRIPTION("PCIXCC Cryptographic Coprocessor device driver, " \
"Copyright IBM Corp. 2001, 2012");
MODULE_LICENSE("GPL");
static struct ap_device_id zcrypt_pcixcc_card_ids[] = {
{ .dev_type = AP_DEVICE_TYPE_PCIXCC,
.match_flags = AP_DEVICE_ID_MATCH_CARD_TYPE },
{ .dev_type = AP_DEVICE_TYPE_CEX2C,
.match_flags = AP_DEVICE_ID_MATCH_CARD_TYPE },
{ .dev_type = AP_DEVICE_TYPE_CEX3C,
.match_flags = AP_DEVICE_ID_MATCH_CARD_TYPE },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(ap, zcrypt_pcixcc_card_ids);
static struct ap_device_id zcrypt_pcixcc_queue_ids[] = {
{ .dev_type = AP_DEVICE_TYPE_PCIXCC,
.match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
{ .dev_type = AP_DEVICE_TYPE_CEX2C,
.match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
{ .dev_type = AP_DEVICE_TYPE_CEX3C,
.match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(ap, zcrypt_pcixcc_queue_ids);
/**
* Large random number detection function. Its sends a message to a pcixcc
* card to find out if large random numbers are supported.
* @ap_dev: pointer to the AP device.
*
* Returns 1 if large random numbers are supported, 0 if not and < 0 on error.
*/
static int zcrypt_pcixcc_rng_supported(struct ap_queue *aq)
{
struct ap_message ap_msg;
unsigned long long psmid;
unsigned int domain;
struct {
struct type86_hdr hdr;
struct type86_fmt2_ext fmt2;
struct CPRBX cprbx;
} __packed *reply;
struct {
struct type6_hdr hdr;
struct CPRBX cprbx;
char function_code[2];
short int rule_length;
char rule[8];
short int verb_length;
short int key_length;
} __packed *msg;
int rc, i;
ap_init_message(&ap_msg);
ap_msg.message = (void *) get_zeroed_page(GFP_KERNEL);
if (!ap_msg.message)
return -ENOMEM;
rng_type6CPRB_msgX(&ap_msg, 4, &domain);
msg = ap_msg.message;
msg->cprbx.domain = AP_QID_QUEUE(aq->qid);
rc = ap_send(aq->qid, 0x0102030405060708ULL, ap_msg.message,
ap_msg.length);
if (rc)
goto out_free;
/* Wait for the test message to complete. */
for (i = 0; i < 2 * HZ; i++) {
msleep(1000 / HZ);
rc = ap_recv(aq->qid, &psmid, ap_msg.message, 4096);
if (rc == 0 && psmid == 0x0102030405060708ULL)
break;
}
if (i >= 2 * HZ) {
/* Got no answer. */
rc = -ENODEV;
goto out_free;
}
reply = ap_msg.message;
if (reply->cprbx.ccp_rtcode == 0 && reply->cprbx.ccp_rscode == 0)
rc = 1;
else
rc = 0;
out_free:
free_page((unsigned long) ap_msg.message);
return rc;
}
/**
* Probe function for PCIXCC/CEX2C card devices. It always accepts the
* AP device since the bus_match already checked the hardware type. The
* PCIXCC cards come in two flavours: micro code level 2 and micro code
* level 3. This is checked by sending a test message to the device.
* @ap_dev: pointer to the AP card device.
*/
static int zcrypt_pcixcc_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 CEX2C_SPEED_IDX[] = {
1000, 1400, 2400, 1100, 1500, 2600, 100, 12};
static const int CEX3C_SPEED_IDX[] = {
500, 700, 1400, 550, 800, 1500, 80, 10};
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;
switch (ac->ap_dev.device_type) {
case AP_DEVICE_TYPE_CEX2C:
zc->user_space_type = ZCRYPT_CEX2C;
zc->type_string = "CEX2C";
memcpy(zc->speed_rating, CEX2C_SPEED_IDX,
sizeof(CEX2C_SPEED_IDX));
zc->min_mod_size = PCIXCC_MIN_MOD_SIZE;
zc->max_mod_size = PCIXCC_MAX_MOD_SIZE;
zc->max_exp_bit_length = PCIXCC_MAX_MOD_SIZE;
break;
case AP_DEVICE_TYPE_CEX3C:
zc->user_space_type = ZCRYPT_CEX3C;
zc->type_string = "CEX3C";
memcpy(zc->speed_rating, CEX3C_SPEED_IDX,
sizeof(CEX3C_SPEED_IDX));
zc->min_mod_size = CEX3C_MIN_MOD_SIZE;
zc->max_mod_size = CEX3C_MAX_MOD_SIZE;
zc->max_exp_bit_length = CEX3C_MAX_MOD_SIZE;
break;
default:
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 PCIXCC/CEX2C card driver information
* if an AP card device is removed.
*/
static void zcrypt_pcixcc_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_pcixcc_card_driver = {
.probe = zcrypt_pcixcc_card_probe,
.remove = zcrypt_pcixcc_card_remove,
.ids = zcrypt_pcixcc_card_ids,
.flags = AP_DRIVER_FLAG_DEFAULT,
};
/**
* Probe function for PCIXCC/CEX2C queue devices. It always accepts the
* AP device since the bus_match already checked the hardware type. The
* PCIXCC cards come in two flavours: micro code level 2 and micro code
* level 3. This is checked by sending a test message to the device.
* @ap_dev: pointer to the AP card device.
*/
static int zcrypt_pcixcc_queue_probe(struct ap_device *ap_dev)
{
struct ap_queue *aq = to_ap_queue(&ap_dev->device);
struct zcrypt_queue *zq;
int rc;
zq = zcrypt_queue_alloc(PCIXCC_MAX_XCRB_MESSAGE_SIZE);
if (!zq)
return -ENOMEM;
zq->queue = aq;
zq->online = 1;
atomic_set(&zq->load, 0);
rc = zcrypt_pcixcc_rng_supported(aq);
if (rc < 0) {
zcrypt_queue_free(zq);
return rc;
}
if (rc)
zq->ops = zcrypt_msgtype(MSGTYPE06_NAME,
MSGTYPE06_VARIANT_DEFAULT);
else
zq->ops = zcrypt_msgtype(MSGTYPE06_NAME,
MSGTYPE06_VARIANT_NORNG);
ap_queue_init_reply(aq, &zq->reply);
aq->request_timeout = PCIXCC_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 PCIXCC/CEX2C queue driver information
* if an AP queue device is removed.
*/
static void zcrypt_pcixcc_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_pcixcc_queue_driver = {
.probe = zcrypt_pcixcc_queue_probe,
.remove = zcrypt_pcixcc_queue_remove,
.suspend = ap_queue_suspend,
.resume = ap_queue_resume,
.ids = zcrypt_pcixcc_queue_ids,
.flags = AP_DRIVER_FLAG_DEFAULT,
};
int __init zcrypt_pcixcc_init(void)
{
int rc;
rc = ap_driver_register(&zcrypt_pcixcc_card_driver,
THIS_MODULE, "pcixcccard");
if (rc)
return rc;
rc = ap_driver_register(&zcrypt_pcixcc_queue_driver,
THIS_MODULE, "pcixccqueue");
if (rc)
ap_driver_unregister(&zcrypt_pcixcc_card_driver);
return rc;
}
void zcrypt_pcixcc_exit(void)
{
ap_driver_unregister(&zcrypt_pcixcc_queue_driver);
ap_driver_unregister(&zcrypt_pcixcc_card_driver);
}
module_init(zcrypt_pcixcc_init);
module_exit(zcrypt_pcixcc_exit);