summaryrefslogtreecommitdiffstats
path: root/drivers/s390/char/sclp_cpi.c
blob: 65aa2c85737fe433e32e231f6b1f7048604ff20c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
/*
 * Author: Martin Peschke <mpeschke@de.ibm.com>
 * Copyright (C) 2001 IBM Entwicklung GmbH, IBM Corporation
 *
 * SCLP Control-Program Identification.
 */

#include <linux/version.h>
#include <linux/kmod.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <asm/ebcdic.h>
#include <asm/semaphore.h>

#include "sclp.h"
#include "sclp_rw.h"

#define CPI_LENGTH_SYSTEM_TYPE	8
#define CPI_LENGTH_SYSTEM_NAME	8
#define CPI_LENGTH_SYSPLEX_NAME	8

struct cpi_evbuf {
	struct evbuf_header header;
	u8	id_format;
	u8	reserved0;
	u8	system_type[CPI_LENGTH_SYSTEM_TYPE];
	u64	reserved1;
	u8	system_name[CPI_LENGTH_SYSTEM_NAME];
	u64	reserved2;
	u64	system_level;
	u64	reserved3;
	u8	sysplex_name[CPI_LENGTH_SYSPLEX_NAME];
	u8	reserved4[16];
} __attribute__((packed));

struct cpi_sccb {
	struct sccb_header header;
	struct cpi_evbuf cpi_evbuf;
} __attribute__((packed));

/* Event type structure for write message and write priority message */
static struct sclp_register sclp_cpi_event =
{
	.send_mask = EvTyp_CtlProgIdent_Mask
};

MODULE_LICENSE("GPL");

MODULE_AUTHOR(
	"Martin Peschke, IBM Deutschland Entwicklung GmbH "
	"<mpeschke@de.ibm.com>");

MODULE_DESCRIPTION(
	"identify this operating system instance to the S/390 "
	"or zSeries hardware");

static char *system_name = NULL;
module_param(system_name, charp, 0);
MODULE_PARM_DESC(system_name, "e.g. hostname - max. 8 characters");

static char *sysplex_name = NULL;
#ifdef ALLOW_SYSPLEX_NAME
module_param(sysplex_name, charp, 0);
MODULE_PARM_DESC(sysplex_name, "if applicable - max. 8 characters");
#endif

/* use default value for this field (as well as for system level) */
static char *system_type = "LINUX";

static int
cpi_check_parms(void)
{
	/* reject if no system type specified */
	if (!system_type) {
		printk("cpi: bug: no system type specified\n");
		return -EINVAL;
	}

	/* reject if system type larger than 8 characters */
	if (strlen(system_type) > CPI_LENGTH_SYSTEM_NAME) {
		printk("cpi: bug: system type has length of %li characters - "
		       "only %i characters supported\n",
		       strlen(system_type), CPI_LENGTH_SYSTEM_TYPE);
		return -EINVAL;
	}

	/* reject if no system name specified */
	if (!system_name) {
		printk("cpi: no system name specified\n");
		return -EINVAL;
	}

	/* reject if system name larger than 8 characters */
	if (strlen(system_name) > CPI_LENGTH_SYSTEM_NAME) {
		printk("cpi: system name has length of %li characters - "
		       "only %i characters supported\n",
		       strlen(system_name), CPI_LENGTH_SYSTEM_NAME);
		return -EINVAL;
	}

	/* reject if specified sysplex name larger than 8 characters */
	if (sysplex_name && strlen(sysplex_name) > CPI_LENGTH_SYSPLEX_NAME) {
		printk("cpi: sysplex name has length of %li characters"
		       " - only %i characters supported\n",
		       strlen(sysplex_name), CPI_LENGTH_SYSPLEX_NAME);
		return -EINVAL;
	}
	return 0;
}

static void
cpi_callback(struct sclp_req *req, void *data)
{
	struct semaphore *sem;

	sem = (struct semaphore *) data;
	up(sem);
}

static struct sclp_req *
cpi_prepare_req(void)
{
	struct sclp_req *req;
	struct cpi_sccb *sccb;
	struct cpi_evbuf *evb;

	req = kmalloc(sizeof(struct sclp_req), GFP_KERNEL);
	if (req == NULL)
		return ERR_PTR(-ENOMEM);
	sccb = (struct cpi_sccb *) __get_free_page(GFP_KERNEL | GFP_DMA);
	if (sccb == NULL) {
		kfree(req);
		return ERR_PTR(-ENOMEM);
	}
	memset(sccb, 0, sizeof(struct cpi_sccb));

	/* setup SCCB for Control-Program Identification */
	sccb->header.length = sizeof(struct cpi_sccb);
	sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
	sccb->cpi_evbuf.header.type = 0x0B;
	evb = &sccb->cpi_evbuf;

	/* set system type */
	memset(evb->system_type, ' ', CPI_LENGTH_SYSTEM_TYPE);
	memcpy(evb->system_type, system_type, strlen(system_type));
	sclp_ascebc_str(evb->system_type, CPI_LENGTH_SYSTEM_TYPE);
	EBC_TOUPPER(evb->system_type, CPI_LENGTH_SYSTEM_TYPE);

	/* set system name */
	memset(evb->system_name, ' ', CPI_LENGTH_SYSTEM_NAME);
	memcpy(evb->system_name, system_name, strlen(system_name));
	sclp_ascebc_str(evb->system_name, CPI_LENGTH_SYSTEM_NAME);
	EBC_TOUPPER(evb->system_name, CPI_LENGTH_SYSTEM_NAME);

	/* set sytem level */
	evb->system_level = LINUX_VERSION_CODE;

	/* set sysplex name */
	if (sysplex_name) {
		memset(evb->sysplex_name, ' ', CPI_LENGTH_SYSPLEX_NAME);
		memcpy(evb->sysplex_name, sysplex_name, strlen(sysplex_name));
		sclp_ascebc_str(evb->sysplex_name, CPI_LENGTH_SYSPLEX_NAME);
		EBC_TOUPPER(evb->sysplex_name, CPI_LENGTH_SYSPLEX_NAME);
	}

	/* prepare request data structure presented to SCLP driver */
	req->command = SCLP_CMDW_WRITE_EVENT_DATA;
	req->sccb = sccb;
	req->status = SCLP_REQ_FILLED;
	req->callback = cpi_callback;
	return req;
}

static void
cpi_free_req(struct sclp_req *req)
{
	free_page((unsigned long) req->sccb);
	kfree(req);
}

static int __init
cpi_module_init(void)
{
	struct semaphore sem;
	struct sclp_req *req;
	int rc;

	rc = cpi_check_parms();
	if (rc)
		return rc;

	rc = sclp_register(&sclp_cpi_event);
	if (rc) {
		/* could not register sclp event. Die. */
		printk(KERN_WARNING "cpi: could not register to hardware "
		       "console.\n");
		return -EINVAL;
	}
	if (!(sclp_cpi_event.sclp_send_mask & EvTyp_CtlProgIdent_Mask)) {
		printk(KERN_WARNING "cpi: no control program identification "
		       "support\n");
		sclp_unregister(&sclp_cpi_event);
		return -EOPNOTSUPP;
	}

	req = cpi_prepare_req();
	if (IS_ERR(req)) {
		printk(KERN_WARNING "cpi: couldn't allocate request\n");
		sclp_unregister(&sclp_cpi_event);
		return PTR_ERR(req);
	}

	/* Prepare semaphore */
	sema_init(&sem, 0);
	req->callback_data = &sem;
	/* Add request to sclp queue */
	rc = sclp_add_request(req);
	if (rc) {
		printk(KERN_WARNING "cpi: could not start request\n");
		cpi_free_req(req);
		sclp_unregister(&sclp_cpi_event);
		return rc;
	}
	/* make "insmod" sleep until callback arrives */
	down(&sem);

	rc = ((struct cpi_sccb *) req->sccb)->header.response_code;
	if (rc != 0x0020) {
		printk(KERN_WARNING "cpi: failed with response code 0x%x\n",
		       rc);
		rc = -ECOMM;
	} else
		rc = 0;

	cpi_free_req(req);
	sclp_unregister(&sclp_cpi_event);

	return rc;
}


static void __exit cpi_module_exit(void)
{
}


/* declare driver module init/cleanup functions */
module_init(cpi_module_init);
module_exit(cpi_module_exit);