1/*
2 *    SCLP OCF communication parameters sysfs interface
3 *
4 *    Copyright IBM Corp. 2011
5 *    Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
6 */
7
8#define KMSG_COMPONENT "sclp_ocf"
9#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/stat.h>
14#include <linux/device.h>
15#include <linux/string.h>
16#include <linux/ctype.h>
17#include <linux/kmod.h>
18#include <linux/timer.h>
19#include <linux/err.h>
20#include <asm/ebcdic.h>
21#include <asm/sclp.h>
22
23#include "sclp.h"
24
25#define OCF_LENGTH_HMC_NETWORK 8UL
26#define OCF_LENGTH_CPC_NAME 8UL
27
28static char hmc_network[OCF_LENGTH_HMC_NETWORK + 1];
29static char cpc_name[OCF_LENGTH_CPC_NAME + 1];
30
31static DEFINE_SPINLOCK(sclp_ocf_lock);
32static struct work_struct sclp_ocf_change_work;
33
34static struct kset *ocf_kset;
35
36static void sclp_ocf_change_notify(struct work_struct *work)
37{
38	kobject_uevent(&ocf_kset->kobj, KOBJ_CHANGE);
39}
40
41/* Handler for OCF event. Look for the CPC image name. */
42static void sclp_ocf_handler(struct evbuf_header *evbuf)
43{
44	struct gds_vector *v;
45	struct gds_subvector *sv, *netid, *cpc;
46	size_t size;
47
48	/* Find the 0x9f00 block. */
49	v = sclp_find_gds_vector(evbuf + 1, (void *) evbuf + evbuf->length,
50				 0x9f00);
51	if (!v)
52		return;
53	/* Find the 0x9f22 block inside the 0x9f00 block. */
54	v = sclp_find_gds_vector(v + 1, (void *) v + v->length, 0x9f22);
55	if (!v)
56		return;
57	/* Find the 0x81 block inside the 0x9f22 block. */
58	sv = sclp_find_gds_subvector(v + 1, (void *) v + v->length, 0x81);
59	if (!sv)
60		return;
61	/* Find the 0x01 block inside the 0x81 block. */
62	netid = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 1);
63	/* Find the 0x02 block inside the 0x81 block. */
64	cpc = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 2);
65	/* Copy network name and cpc name. */
66	spin_lock(&sclp_ocf_lock);
67	if (netid) {
68		size = min(OCF_LENGTH_HMC_NETWORK, (size_t) netid->length);
69		memcpy(hmc_network, netid + 1, size);
70		EBCASC(hmc_network, size);
71		hmc_network[size] = 0;
72	}
73	if (cpc) {
74		size = min(OCF_LENGTH_CPC_NAME, (size_t) cpc->length);
75		memcpy(cpc_name, cpc + 1, size);
76		EBCASC(cpc_name, size);
77		cpc_name[size] = 0;
78	}
79	spin_unlock(&sclp_ocf_lock);
80	schedule_work(&sclp_ocf_change_work);
81}
82
83static struct sclp_register sclp_ocf_event = {
84	.receive_mask = EVTYP_OCF_MASK,
85	.receiver_fn = sclp_ocf_handler,
86};
87
88static ssize_t cpc_name_show(struct kobject *kobj,
89			     struct kobj_attribute *attr, char *page)
90{
91	int rc;
92
93	spin_lock_irq(&sclp_ocf_lock);
94	rc = snprintf(page, PAGE_SIZE, "%s\n", cpc_name);
95	spin_unlock_irq(&sclp_ocf_lock);
96	return rc;
97}
98
99static struct kobj_attribute cpc_name_attr =
100	__ATTR(cpc_name, 0444, cpc_name_show, NULL);
101
102static ssize_t hmc_network_show(struct kobject *kobj,
103				struct kobj_attribute *attr, char *page)
104{
105	int rc;
106
107	spin_lock_irq(&sclp_ocf_lock);
108	rc = snprintf(page, PAGE_SIZE, "%s\n", hmc_network);
109	spin_unlock_irq(&sclp_ocf_lock);
110	return rc;
111}
112
113static struct kobj_attribute hmc_network_attr =
114	__ATTR(hmc_network, 0444, hmc_network_show, NULL);
115
116static struct attribute *ocf_attrs[] = {
117	&cpc_name_attr.attr,
118	&hmc_network_attr.attr,
119	NULL,
120};
121
122static struct attribute_group ocf_attr_group = {
123	.attrs = ocf_attrs,
124};
125
126static int __init ocf_init(void)
127{
128	int rc;
129
130	INIT_WORK(&sclp_ocf_change_work, sclp_ocf_change_notify);
131	ocf_kset = kset_create_and_add("ocf", NULL, firmware_kobj);
132	if (!ocf_kset)
133		return -ENOMEM;
134
135	rc = sysfs_create_group(&ocf_kset->kobj, &ocf_attr_group);
136	if (rc) {
137		kset_unregister(ocf_kset);
138		return rc;
139	}
140
141	return sclp_register(&sclp_ocf_event);
142}
143
144device_initcall(ocf_init);
145