1// SPDX-License-Identifier: GPL-2.0
2/*
3 * SCLP OCF communication parameters sysfs interface
4 *
5 * Copyright IBM Corp. 2011
6 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
7 */
8
9#define KMSG_COMPONENT "sclp_ocf"
10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12#include <linux/kernel.h>
13#include <linux/init.h>
14#include <linux/stat.h>
15#include <linux/device.h>
16#include <linux/string.h>
17#include <linux/ctype.h>
18#include <linux/kmod.h>
19#include <linux/timer.h>
20#include <linux/err.h>
21#include <asm/ebcdic.h>
22#include <asm/sclp.h>
23
24#include "sclp.h"
25
26#define OCF_LENGTH_HMC_NETWORK 8UL
27#define OCF_LENGTH_CPC_NAME 8UL
28
29static char hmc_network[OCF_LENGTH_HMC_NETWORK + 1];
30static char cpc_name[OCF_LENGTH_CPC_NAME]; /* in EBCDIC */
31
32static DEFINE_SPINLOCK(sclp_ocf_lock);
33static struct work_struct sclp_ocf_change_work;
34
35static struct kset *ocf_kset;
36
37static void sclp_ocf_change_notify(struct work_struct *work)
38{
39 kobject_uevent(kobj: &ocf_kset->kobj, action: KOBJ_CHANGE);
40}
41
42/* Handler for OCF event. Look for the CPC image name. */
43static void sclp_ocf_handler(struct evbuf_header *evbuf)
44{
45 struct gds_vector *v;
46 struct gds_subvector *sv, *netid, *cpc;
47 size_t size;
48
49 /* Find the 0x9f00 block. */
50 v = sclp_find_gds_vector(start: evbuf + 1, end: (void *) evbuf + evbuf->length,
51 id: 0x9f00);
52 if (!v)
53 return;
54 /* Find the 0x9f22 block inside the 0x9f00 block. */
55 v = sclp_find_gds_vector(start: v + 1, end: (void *) v + v->length, id: 0x9f22);
56 if (!v)
57 return;
58 /* Find the 0x81 block inside the 0x9f22 block. */
59 sv = sclp_find_gds_subvector(start: v + 1, end: (void *) v + v->length, key: 0x81);
60 if (!sv)
61 return;
62 /* Find the 0x01 block inside the 0x81 block. */
63 netid = sclp_find_gds_subvector(start: sv + 1, end: (void *) sv + sv->length, key: 1);
64 /* Find the 0x02 block inside the 0x81 block. */
65 cpc = sclp_find_gds_subvector(start: sv + 1, end: (void *) sv + sv->length, key: 2);
66 /* Copy network name and cpc name. */
67 spin_lock(lock: &sclp_ocf_lock);
68 if (netid) {
69 size = min(OCF_LENGTH_HMC_NETWORK, (size_t) netid->length);
70 memcpy(hmc_network, netid + 1, size);
71 EBCASC(hmc_network, size);
72 hmc_network[size] = 0;
73 }
74 if (cpc) {
75 size = min(OCF_LENGTH_CPC_NAME, (size_t) cpc->length);
76 memset(cpc_name, 0, OCF_LENGTH_CPC_NAME);
77 memcpy(cpc_name, cpc + 1, size);
78 }
79 spin_unlock(lock: &sclp_ocf_lock);
80 schedule_work(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
88void sclp_ocf_cpc_name_copy(char *dst)
89{
90 spin_lock_irq(lock: &sclp_ocf_lock);
91 memcpy(dst, cpc_name, OCF_LENGTH_CPC_NAME);
92 spin_unlock_irq(lock: &sclp_ocf_lock);
93}
94EXPORT_SYMBOL(sclp_ocf_cpc_name_copy);
95
96static ssize_t cpc_name_show(struct kobject *kobj,
97 struct kobj_attribute *attr, char *page)
98{
99 char name[OCF_LENGTH_CPC_NAME + 1];
100
101 sclp_ocf_cpc_name_copy(name);
102 name[OCF_LENGTH_CPC_NAME] = 0;
103 EBCASC(name, OCF_LENGTH_CPC_NAME);
104 return snprintf(buf: page, PAGE_SIZE, fmt: "%s\n", name);
105}
106
107static struct kobj_attribute cpc_name_attr =
108 __ATTR(cpc_name, 0444, cpc_name_show, NULL);
109
110static ssize_t hmc_network_show(struct kobject *kobj,
111 struct kobj_attribute *attr, char *page)
112{
113 int rc;
114
115 spin_lock_irq(lock: &sclp_ocf_lock);
116 rc = snprintf(buf: page, PAGE_SIZE, fmt: "%s\n", hmc_network);
117 spin_unlock_irq(lock: &sclp_ocf_lock);
118 return rc;
119}
120
121static struct kobj_attribute hmc_network_attr =
122 __ATTR(hmc_network, 0444, hmc_network_show, NULL);
123
124static struct attribute *ocf_attrs[] = {
125 &cpc_name_attr.attr,
126 &hmc_network_attr.attr,
127 NULL,
128};
129
130static const struct attribute_group ocf_attr_group = {
131 .attrs = ocf_attrs,
132};
133
134static int __init ocf_init(void)
135{
136 int rc;
137
138 INIT_WORK(&sclp_ocf_change_work, sclp_ocf_change_notify);
139 ocf_kset = kset_create_and_add(name: "ocf", NULL, parent_kobj: firmware_kobj);
140 if (!ocf_kset)
141 return -ENOMEM;
142
143 rc = sysfs_create_group(kobj: &ocf_kset->kobj, grp: &ocf_attr_group);
144 if (rc) {
145 kset_unregister(kset: ocf_kset);
146 return rc;
147 }
148
149 return sclp_register(reg: &sclp_ocf_event);
150}
151
152device_initcall(ocf_init);
153

source code of linux/drivers/s390/char/sclp_ocf.c