linux/linux-5.4.31/drivers/s390/char/sclp_ocf.c

153 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* SCLP OCF communication parameters sysfs interface
*
* Copyright IBM Corp. 2011
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#define KMSG_COMPONENT "sclp_ocf"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/stat.h>
#include <linux/device.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/kmod.h>
#include <linux/timer.h>
#include <linux/err.h>
#include <asm/ebcdic.h>
#include <asm/sclp.h>
#include "sclp.h"
#define OCF_LENGTH_HMC_NETWORK 8UL
#define OCF_LENGTH_CPC_NAME 8UL
static char hmc_network[OCF_LENGTH_HMC_NETWORK + 1];
static char cpc_name[OCF_LENGTH_CPC_NAME]; /* in EBCDIC */
static DEFINE_SPINLOCK(sclp_ocf_lock);
static struct work_struct sclp_ocf_change_work;
static struct kset *ocf_kset;
static void sclp_ocf_change_notify(struct work_struct *work)
{
kobject_uevent(&ocf_kset->kobj, KOBJ_CHANGE);
}
/* Handler for OCF event. Look for the CPC image name. */
static void sclp_ocf_handler(struct evbuf_header *evbuf)
{
struct gds_vector *v;
struct gds_subvector *sv, *netid, *cpc;
size_t size;
/* Find the 0x9f00 block. */
v = sclp_find_gds_vector(evbuf + 1, (void *) evbuf + evbuf->length,
0x9f00);
if (!v)
return;
/* Find the 0x9f22 block inside the 0x9f00 block. */
v = sclp_find_gds_vector(v + 1, (void *) v + v->length, 0x9f22);
if (!v)
return;
/* Find the 0x81 block inside the 0x9f22 block. */
sv = sclp_find_gds_subvector(v + 1, (void *) v + v->length, 0x81);
if (!sv)
return;
/* Find the 0x01 block inside the 0x81 block. */
netid = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 1);
/* Find the 0x02 block inside the 0x81 block. */
cpc = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 2);
/* Copy network name and cpc name. */
spin_lock(&sclp_ocf_lock);
if (netid) {
size = min(OCF_LENGTH_HMC_NETWORK, (size_t) netid->length);
memcpy(hmc_network, netid + 1, size);
EBCASC(hmc_network, size);
hmc_network[size] = 0;
}
if (cpc) {
size = min(OCF_LENGTH_CPC_NAME, (size_t) cpc->length);
memset(cpc_name, 0, OCF_LENGTH_CPC_NAME);
memcpy(cpc_name, cpc + 1, size);
}
spin_unlock(&sclp_ocf_lock);
schedule_work(&sclp_ocf_change_work);
}
static struct sclp_register sclp_ocf_event = {
.receive_mask = EVTYP_OCF_MASK,
.receiver_fn = sclp_ocf_handler,
};
void sclp_ocf_cpc_name_copy(char *dst)
{
spin_lock_irq(&sclp_ocf_lock);
memcpy(dst, cpc_name, OCF_LENGTH_CPC_NAME);
spin_unlock_irq(&sclp_ocf_lock);
}
EXPORT_SYMBOL(sclp_ocf_cpc_name_copy);
static ssize_t cpc_name_show(struct kobject *kobj,
struct kobj_attribute *attr, char *page)
{
char name[OCF_LENGTH_CPC_NAME + 1];
sclp_ocf_cpc_name_copy(name);
name[OCF_LENGTH_CPC_NAME] = 0;
EBCASC(name, OCF_LENGTH_CPC_NAME);
return snprintf(page, PAGE_SIZE, "%s\n", name);
}
static struct kobj_attribute cpc_name_attr =
__ATTR(cpc_name, 0444, cpc_name_show, NULL);
static ssize_t hmc_network_show(struct kobject *kobj,
struct kobj_attribute *attr, char *page)
{
int rc;
spin_lock_irq(&sclp_ocf_lock);
rc = snprintf(page, PAGE_SIZE, "%s\n", hmc_network);
spin_unlock_irq(&sclp_ocf_lock);
return rc;
}
static struct kobj_attribute hmc_network_attr =
__ATTR(hmc_network, 0444, hmc_network_show, NULL);
static struct attribute *ocf_attrs[] = {
&cpc_name_attr.attr,
&hmc_network_attr.attr,
NULL,
};
static const struct attribute_group ocf_attr_group = {
.attrs = ocf_attrs,
};
static int __init ocf_init(void)
{
int rc;
INIT_WORK(&sclp_ocf_change_work, sclp_ocf_change_notify);
ocf_kset = kset_create_and_add("ocf", NULL, firmware_kobj);
if (!ocf_kset)
return -ENOMEM;
rc = sysfs_create_group(&ocf_kset->kobj, &ocf_attr_group);
if (rc) {
kset_unregister(ocf_kset);
return rc;
}
return sclp_register(&sclp_ocf_event);
}
device_initcall(ocf_init);