linux-stable/drivers/s390/net/smsgiucv.c
Martin Schwidefsky 760dd0eeae s390/smsgiucv: disable SMSG on module unload
The module exit function of the smsgiucv module uses the incorrect CP
command to disable SMSG messages. The correct command is "SET SMSG OFF".
Use it.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-16 09:10:17 +02:00

245 lines
5.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* IUCV special message driver
*
* Copyright IBM Corp. 2003, 2009
*
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <net/iucv/iucv.h>
#include <asm/cpcmd.h>
#include <asm/ebcdic.h>
#include "smsgiucv.h"
struct smsg_callback {
struct list_head list;
const char *prefix;
int len;
void (*callback)(const char *from, char *str);
};
MODULE_AUTHOR
("(C) 2003 IBM Corporation by Martin Schwidefsky (schwidefsky@de.ibm.com)");
MODULE_DESCRIPTION ("Linux for S/390 IUCV special message driver");
static struct iucv_path *smsg_path;
/* dummy device used as trigger for PM functions */
static struct device *smsg_dev;
static DEFINE_SPINLOCK(smsg_list_lock);
static LIST_HEAD(smsg_list);
static int iucv_path_connected;
static int smsg_path_pending(struct iucv_path *, u8 *, u8 *);
static void smsg_message_pending(struct iucv_path *, struct iucv_message *);
static struct iucv_handler smsg_handler = {
.path_pending = smsg_path_pending,
.message_pending = smsg_message_pending,
};
static int smsg_path_pending(struct iucv_path *path, u8 *ipvmid, u8 *ipuser)
{
if (strncmp(ipvmid, "*MSG ", 8) != 0)
return -EINVAL;
/* Path pending from *MSG. */
return iucv_path_accept(path, &smsg_handler, "SMSGIUCV ", NULL);
}
static void smsg_message_pending(struct iucv_path *path,
struct iucv_message *msg)
{
struct smsg_callback *cb;
unsigned char *buffer;
unsigned char sender[9];
int rc, i;
buffer = kmalloc(msg->length + 1, GFP_ATOMIC | GFP_DMA);
if (!buffer) {
iucv_message_reject(path, msg);
return;
}
rc = iucv_message_receive(path, msg, 0, buffer, msg->length, NULL);
if (rc == 0) {
buffer[msg->length] = 0;
EBCASC(buffer, msg->length);
memcpy(sender, buffer, 8);
sender[8] = 0;
/* Remove trailing whitespace from the sender name. */
for (i = 7; i >= 0; i--) {
if (sender[i] != ' ' && sender[i] != '\t')
break;
sender[i] = 0;
}
spin_lock(&smsg_list_lock);
list_for_each_entry(cb, &smsg_list, list)
if (strncmp(buffer + 8, cb->prefix, cb->len) == 0) {
cb->callback(sender, buffer + 8);
break;
}
spin_unlock(&smsg_list_lock);
}
kfree(buffer);
}
int smsg_register_callback(const char *prefix,
void (*callback)(const char *from, char *str))
{
struct smsg_callback *cb;
cb = kmalloc(sizeof(struct smsg_callback), GFP_KERNEL);
if (!cb)
return -ENOMEM;
cb->prefix = prefix;
cb->len = strlen(prefix);
cb->callback = callback;
spin_lock_bh(&smsg_list_lock);
list_add_tail(&cb->list, &smsg_list);
spin_unlock_bh(&smsg_list_lock);
return 0;
}
void smsg_unregister_callback(const char *prefix,
void (*callback)(const char *from,
char *str))
{
struct smsg_callback *cb, *tmp;
spin_lock_bh(&smsg_list_lock);
cb = NULL;
list_for_each_entry(tmp, &smsg_list, list)
if (tmp->callback == callback &&
strcmp(tmp->prefix, prefix) == 0) {
cb = tmp;
list_del(&cb->list);
break;
}
spin_unlock_bh(&smsg_list_lock);
kfree(cb);
}
static int smsg_pm_freeze(struct device *dev)
{
#ifdef CONFIG_PM_DEBUG
printk(KERN_WARNING "smsg_pm_freeze\n");
#endif
if (smsg_path && iucv_path_connected) {
iucv_path_sever(smsg_path, NULL);
iucv_path_connected = 0;
}
return 0;
}
static int smsg_pm_restore_thaw(struct device *dev)
{
int rc;
#ifdef CONFIG_PM_DEBUG
printk(KERN_WARNING "smsg_pm_restore_thaw\n");
#endif
if (smsg_path && !iucv_path_connected) {
memset(smsg_path, 0, sizeof(*smsg_path));
smsg_path->msglim = 255;
smsg_path->flags = 0;
rc = iucv_path_connect(smsg_path, &smsg_handler, "*MSG ",
NULL, NULL, NULL);
#ifdef CONFIG_PM_DEBUG
if (rc)
printk(KERN_ERR
"iucv_path_connect returned with rc %i\n", rc);
#endif
if (!rc)
iucv_path_connected = 1;
cpcmd("SET SMSG IUCV", NULL, 0, NULL);
}
return 0;
}
static const struct dev_pm_ops smsg_pm_ops = {
.freeze = smsg_pm_freeze,
.thaw = smsg_pm_restore_thaw,
.restore = smsg_pm_restore_thaw,
};
static struct device_driver smsg_driver = {
.owner = THIS_MODULE,
.name = SMSGIUCV_DRV_NAME,
.bus = &iucv_bus,
.pm = &smsg_pm_ops,
};
static void __exit smsg_exit(void)
{
cpcmd("SET SMSG OFF", NULL, 0, NULL);
device_unregister(smsg_dev);
iucv_unregister(&smsg_handler, 1);
driver_unregister(&smsg_driver);
}
static int __init smsg_init(void)
{
int rc;
if (!MACHINE_IS_VM) {
rc = -EPROTONOSUPPORT;
goto out;
}
rc = driver_register(&smsg_driver);
if (rc != 0)
goto out;
rc = iucv_register(&smsg_handler, 1);
if (rc)
goto out_driver;
smsg_path = iucv_path_alloc(255, 0, GFP_KERNEL);
if (!smsg_path) {
rc = -ENOMEM;
goto out_register;
}
rc = iucv_path_connect(smsg_path, &smsg_handler, "*MSG ",
NULL, NULL, NULL);
if (rc)
goto out_free_path;
else
iucv_path_connected = 1;
smsg_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
if (!smsg_dev) {
rc = -ENOMEM;
goto out_free_path;
}
dev_set_name(smsg_dev, "smsg_iucv");
smsg_dev->bus = &iucv_bus;
smsg_dev->parent = iucv_root;
smsg_dev->release = (void (*)(struct device *))kfree;
smsg_dev->driver = &smsg_driver;
rc = device_register(smsg_dev);
if (rc)
goto out_put;
cpcmd("SET SMSG IUCV", NULL, 0, NULL);
return 0;
out_put:
put_device(smsg_dev);
out_free_path:
iucv_path_free(smsg_path);
smsg_path = NULL;
out_register:
iucv_unregister(&smsg_handler, 1);
out_driver:
driver_unregister(&smsg_driver);
out:
return rc;
}
module_init(smsg_init);
module_exit(smsg_exit);
MODULE_LICENSE("GPL");
EXPORT_SYMBOL(smsg_register_callback);
EXPORT_SYMBOL(smsg_unregister_callback);