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/export.h>
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/stat.h>
16 #include <linux/device.h>
17 #include <linux/string.h>
18 #include <linux/ctype.h>
19 #include <linux/kmod.h>
20 #include <linux/timer.h>
21 #include <linux/err.h>
22 #include <asm/ebcdic.h>
23 #include <asm/sclp.h>
24
25 #include "sclp.h"
26
27 #define OCF_LENGTH_HMC_NETWORK 8UL
28 #define OCF_LENGTH_CPC_NAME 8UL
29
30 static char hmc_network[OCF_LENGTH_HMC_NETWORK + 1];
31 static char cpc_name[OCF_LENGTH_CPC_NAME]; /* in EBCDIC */
32
33 static DEFINE_SPINLOCK(sclp_ocf_lock);
34 static struct work_struct sclp_ocf_change_work;
35
36 static struct kset *ocf_kset;
37
sclp_ocf_change_notify(struct work_struct * work)38 static void sclp_ocf_change_notify(struct work_struct *work)
39 {
40 kobject_uevent(&ocf_kset->kobj, KOBJ_CHANGE);
41 }
42
43 /* Handler for OCF event. Look for the CPC image name. */
sclp_ocf_handler(struct evbuf_header * evbuf)44 static void sclp_ocf_handler(struct evbuf_header *evbuf)
45 {
46 struct gds_vector *v;
47 struct gds_subvector *sv, *netid, *cpc;
48 size_t size;
49
50 /* Find the 0x9f00 block. */
51 v = sclp_find_gds_vector(evbuf + 1, (void *) evbuf + evbuf->length,
52 0x9f00);
53 if (!v)
54 return;
55 /* Find the 0x9f22 block inside the 0x9f00 block. */
56 v = sclp_find_gds_vector(v + 1, (void *) v + v->length, 0x9f22);
57 if (!v)
58 return;
59 /* Find the 0x81 block inside the 0x9f22 block. */
60 sv = sclp_find_gds_subvector(v + 1, (void *) v + v->length, 0x81);
61 if (!sv)
62 return;
63 /* Find the 0x01 block inside the 0x81 block. */
64 netid = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 1);
65 /* Find the 0x02 block inside the 0x81 block. */
66 cpc = sclp_find_gds_subvector(sv + 1, (void *) sv + sv->length, 2);
67 /* Copy network name and cpc name. */
68 spin_lock(&sclp_ocf_lock);
69 if (netid) {
70 size = min(OCF_LENGTH_HMC_NETWORK, (size_t) netid->length);
71 memcpy(hmc_network, netid + 1, size);
72 EBCASC(hmc_network, size);
73 hmc_network[size] = 0;
74 }
75 if (cpc) {
76 size = min(OCF_LENGTH_CPC_NAME, (size_t) cpc->length);
77 memset(cpc_name, 0, OCF_LENGTH_CPC_NAME);
78 memcpy(cpc_name, cpc + 1, size);
79 }
80 spin_unlock(&sclp_ocf_lock);
81 schedule_work(&sclp_ocf_change_work);
82 }
83
84 static struct sclp_register sclp_ocf_event = {
85 .receive_mask = EVTYP_OCF_MASK,
86 .receiver_fn = sclp_ocf_handler,
87 };
88
sclp_ocf_cpc_name_copy(char * dst)89 void sclp_ocf_cpc_name_copy(char *dst)
90 {
91 spin_lock_irq(&sclp_ocf_lock);
92 memcpy(dst, cpc_name, OCF_LENGTH_CPC_NAME);
93 spin_unlock_irq(&sclp_ocf_lock);
94 }
95 EXPORT_SYMBOL(sclp_ocf_cpc_name_copy);
96
cpc_name_show(struct kobject * kobj,struct kobj_attribute * attr,char * page)97 static ssize_t cpc_name_show(struct kobject *kobj,
98 struct kobj_attribute *attr, char *page)
99 {
100 char name[OCF_LENGTH_CPC_NAME + 1];
101
102 sclp_ocf_cpc_name_copy(name);
103 name[OCF_LENGTH_CPC_NAME] = 0;
104 EBCASC(name, OCF_LENGTH_CPC_NAME);
105 return sysfs_emit(page, "%s\n", name);
106 }
107
108 static struct kobj_attribute cpc_name_attr =
109 __ATTR(cpc_name, 0444, cpc_name_show, NULL);
110
hmc_network_show(struct kobject * kobj,struct kobj_attribute * attr,char * page)111 static ssize_t hmc_network_show(struct kobject *kobj,
112 struct kobj_attribute *attr, char *page)
113 {
114 int rc;
115
116 spin_lock_irq(&sclp_ocf_lock);
117 rc = sysfs_emit(page, "%s\n", hmc_network);
118 spin_unlock_irq(&sclp_ocf_lock);
119 return rc;
120 }
121
122 static struct kobj_attribute hmc_network_attr =
123 __ATTR(hmc_network, 0444, hmc_network_show, NULL);
124
125 static struct attribute *ocf_attrs[] = {
126 &cpc_name_attr.attr,
127 &hmc_network_attr.attr,
128 NULL,
129 };
130
131 static const struct attribute_group ocf_attr_group = {
132 .attrs = ocf_attrs,
133 };
134
ocf_init(void)135 static int __init ocf_init(void)
136 {
137 int rc;
138
139 INIT_WORK(&sclp_ocf_change_work, sclp_ocf_change_notify);
140 ocf_kset = kset_create_and_add("ocf", NULL, firmware_kobj);
141 if (!ocf_kset)
142 return -ENOMEM;
143
144 rc = sysfs_create_group(&ocf_kset->kobj, &ocf_attr_group);
145 if (rc) {
146 kset_unregister(ocf_kset);
147 return rc;
148 }
149
150 return sclp_register(&sclp_ocf_event);
151 }
152
153 device_initcall(ocf_init);
154