tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * drivers/s390/char/sclp_ocf.c
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 + 1];
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(&ocf_kset->kobj, 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(evbuf + 1, (void *) evbuf + evbuf->length,
51 0x9f00);
52 if (!v)
53 return;
54 /* Find the 0x9f22 block inside the 0x9f00 block. */
55 v = sclp_find_gds_vector(v + 1, (void *) v + v->length, 0x9f22);
56 if (!v)
57 return;
58 /* Find the 0x81 block inside the 0x9f22 block. */
59 sv = sclp_find_gds_subvector(v + 1, (void *) v + v->length, 0x81);
60 if (!sv)
61 return;
62 /* Find the 0x01 block inside the 0x81 block. */
63 netid = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 1);
64 /* Find the 0x02 block inside the 0x81 block. */
65 cpc = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 2);
66 /* Copy network name and cpc name. */
67 spin_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 memcpy(cpc_name, cpc + 1, size);
77 EBCASC(cpc_name, size);
78 cpc_name[size] = 0;
79 }
80 spin_unlock(&sclp_ocf_lock);
81 schedule_work(&sclp_ocf_change_work);
82}
83
84static struct sclp_register sclp_ocf_event = {
85 .receive_mask = EVTYP_OCF_MASK,
86 .receiver_fn = sclp_ocf_handler,
87};
88
89static ssize_t cpc_name_show(struct kobject *kobj,
90 struct kobj_attribute *attr, char *page)
91{
92 int rc;
93
94 spin_lock_irq(&sclp_ocf_lock);
95 rc = snprintf(page, PAGE_SIZE, "%s\n", cpc_name);
96 spin_unlock_irq(&sclp_ocf_lock);
97 return rc;
98}
99
100static struct kobj_attribute cpc_name_attr =
101 __ATTR(cpc_name, 0444, cpc_name_show, NULL);
102
103static ssize_t hmc_network_show(struct kobject *kobj,
104 struct kobj_attribute *attr, char *page)
105{
106 int rc;
107
108 spin_lock_irq(&sclp_ocf_lock);
109 rc = snprintf(page, PAGE_SIZE, "%s\n", hmc_network);
110 spin_unlock_irq(&sclp_ocf_lock);
111 return rc;
112}
113
114static struct kobj_attribute hmc_network_attr =
115 __ATTR(hmc_network, 0444, hmc_network_show, NULL);
116
117static struct attribute *ocf_attrs[] = {
118 &cpc_name_attr.attr,
119 &hmc_network_attr.attr,
120 NULL,
121};
122
123static struct attribute_group ocf_attr_group = {
124 .attrs = ocf_attrs,
125};
126
127static int __init ocf_init(void)
128{
129 int rc;
130
131 INIT_WORK(&sclp_ocf_change_work, sclp_ocf_change_notify);
132 ocf_kset = kset_create_and_add("ocf", NULL, firmware_kobj);
133 if (!ocf_kset)
134 return -ENOMEM;
135
136 rc = sysfs_create_group(&ocf_kset->kobj, &ocf_attr_group);
137 if (rc) {
138 kset_unregister(ocf_kset);
139 return rc;
140 }
141
142 return sclp_register(&sclp_ocf_event);
143}
144
145device_initcall(ocf_init);