1// SPDX-License-Identifier: GPL-2.0
2/*
3 * SCLP control program identification sysfs interface
4 *
5 * Copyright IBM Corp. 2001, 2007
6 * Author(s): Martin Peschke <mpeschke@de.ibm.com>
7 * Michael Ernst <mernst@de.ibm.com>
8 */
9
10#define KMSG_COMPONENT "sclp_cpi"
11#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
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 <linux/slab.h>
23#include <linux/completion.h>
24#include <linux/export.h>
25#include <asm/ebcdic.h>
26#include <asm/sclp.h>
27
28#include "sclp.h"
29#include "sclp_rw.h"
30#include "sclp_cpi_sys.h"
31
32#define CPI_LENGTH_NAME 8
33#define CPI_LENGTH_LEVEL 16
34
35static DEFINE_MUTEX(sclp_cpi_mutex);
36
37struct cpi_evbuf {
38 struct evbuf_header header;
39 u8 id_format;
40 u8 reserved0;
41 u8 system_type[CPI_LENGTH_NAME];
42 u64 reserved1;
43 u8 system_name[CPI_LENGTH_NAME];
44 u64 reserved2;
45 u64 system_level;
46 u64 reserved3;
47 u8 sysplex_name[CPI_LENGTH_NAME];
48 u8 reserved4[16];
49} __attribute__((packed));
50
51struct cpi_sccb {
52 struct sccb_header header;
53 struct cpi_evbuf cpi_evbuf;
54} __attribute__((packed));
55
56static struct sclp_register sclp_cpi_event = {
57 .send_mask = EVTYP_CTLPROGIDENT_MASK,
58};
59
60static char system_name[CPI_LENGTH_NAME + 1];
61static char sysplex_name[CPI_LENGTH_NAME + 1];
62static char system_type[CPI_LENGTH_NAME + 1];
63static u64 system_level;
64
65static void set_data(char *field, char *data)
66{
67 memset(field, ' ', CPI_LENGTH_NAME);
68 memcpy(field, data, strlen(data));
69 sclp_ascebc_str(str: field, CPI_LENGTH_NAME);
70}
71
72static void cpi_callback(struct sclp_req *req, void *data)
73{
74 struct completion *completion = data;
75
76 complete(completion);
77}
78
79static struct sclp_req *cpi_prepare_req(void)
80{
81 struct sclp_req *req;
82 struct cpi_sccb *sccb;
83 struct cpi_evbuf *evb;
84
85 req = kzalloc(size: sizeof(struct sclp_req), GFP_KERNEL);
86 if (!req)
87 return ERR_PTR(error: -ENOMEM);
88 sccb = (struct cpi_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
89 if (!sccb) {
90 kfree(objp: req);
91 return ERR_PTR(error: -ENOMEM);
92 }
93
94 /* setup SCCB for Control-Program Identification */
95 sccb->header.length = sizeof(struct cpi_sccb);
96 sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
97 sccb->cpi_evbuf.header.type = EVTYP_CTLPROGIDENT;
98 evb = &sccb->cpi_evbuf;
99
100 /* set system type */
101 set_data(field: evb->system_type, data: system_type);
102
103 /* set system name */
104 set_data(field: evb->system_name, data: system_name);
105
106 /* set system level */
107 evb->system_level = system_level;
108
109 /* set sysplex name */
110 set_data(field: evb->sysplex_name, data: sysplex_name);
111
112 /* prepare request data structure presented to SCLP driver */
113 req->command = SCLP_CMDW_WRITE_EVENT_DATA;
114 req->sccb = sccb;
115 req->status = SCLP_REQ_FILLED;
116 req->callback = cpi_callback;
117 return req;
118}
119
120static void cpi_free_req(struct sclp_req *req)
121{
122 free_page((unsigned long) req->sccb);
123 kfree(objp: req);
124}
125
126static int cpi_req(void)
127{
128 struct completion completion;
129 struct sclp_req *req;
130 int rc;
131 int response;
132
133 rc = sclp_register(reg: &sclp_cpi_event);
134 if (rc)
135 goto out;
136 if (!(sclp_cpi_event.sclp_receive_mask & EVTYP_CTLPROGIDENT_MASK)) {
137 rc = -EOPNOTSUPP;
138 goto out_unregister;
139 }
140
141 req = cpi_prepare_req();
142 if (IS_ERR(ptr: req)) {
143 rc = PTR_ERR(ptr: req);
144 goto out_unregister;
145 }
146
147 init_completion(x: &completion);
148 req->callback_data = &completion;
149
150 /* Add request to sclp queue */
151 rc = sclp_add_request(req);
152 if (rc)
153 goto out_free_req;
154
155 wait_for_completion(&completion);
156
157 if (req->status != SCLP_REQ_DONE) {
158 pr_warn("request failed (status=0x%02x)\n", req->status);
159 rc = -EIO;
160 goto out_free_req;
161 }
162
163 response = ((struct cpi_sccb *) req->sccb)->header.response_code;
164 if (response != 0x0020) {
165 pr_warn("request failed with response code 0x%x\n", response);
166 rc = -EIO;
167 }
168
169out_free_req:
170 cpi_free_req(req);
171
172out_unregister:
173 sclp_unregister(reg: &sclp_cpi_event);
174
175out:
176 return rc;
177}
178
179static int check_string(const char *attr, const char *str)
180{
181 size_t len;
182 size_t i;
183
184 len = strlen(str);
185
186 if ((len > 0) && (str[len - 1] == '\n'))
187 len--;
188
189 if (len > CPI_LENGTH_NAME)
190 return -EINVAL;
191
192 for (i = 0; i < len ; i++) {
193 if (isalpha(str[i]) || isdigit(c: str[i]) ||
194 strchr("$@# ", str[i]))
195 continue;
196 return -EINVAL;
197 }
198
199 return 0;
200}
201
202static void set_string(char *attr, const char *value)
203{
204 size_t len;
205 size_t i;
206
207 len = strlen(value);
208
209 if ((len > 0) && (value[len - 1] == '\n'))
210 len--;
211
212 for (i = 0; i < CPI_LENGTH_NAME; i++) {
213 if (i < len)
214 attr[i] = toupper(value[i]);
215 else
216 attr[i] = ' ';
217 }
218}
219
220static ssize_t system_name_show(struct kobject *kobj,
221 struct kobj_attribute *attr, char *page)
222{
223 int rc;
224
225 mutex_lock(&sclp_cpi_mutex);
226 rc = snprintf(buf: page, PAGE_SIZE, fmt: "%s\n", system_name);
227 mutex_unlock(lock: &sclp_cpi_mutex);
228 return rc;
229}
230
231static ssize_t system_name_store(struct kobject *kobj,
232 struct kobj_attribute *attr,
233 const char *buf,
234 size_t len)
235{
236 int rc;
237
238 rc = check_string(attr: "system_name", str: buf);
239 if (rc)
240 return rc;
241
242 mutex_lock(&sclp_cpi_mutex);
243 set_string(attr: system_name, value: buf);
244 mutex_unlock(lock: &sclp_cpi_mutex);
245
246 return len;
247}
248
249static struct kobj_attribute system_name_attr =
250 __ATTR(system_name, 0644, system_name_show, system_name_store);
251
252static ssize_t sysplex_name_show(struct kobject *kobj,
253 struct kobj_attribute *attr, char *page)
254{
255 int rc;
256
257 mutex_lock(&sclp_cpi_mutex);
258 rc = snprintf(buf: page, PAGE_SIZE, fmt: "%s\n", sysplex_name);
259 mutex_unlock(lock: &sclp_cpi_mutex);
260 return rc;
261}
262
263static ssize_t sysplex_name_store(struct kobject *kobj,
264 struct kobj_attribute *attr,
265 const char *buf,
266 size_t len)
267{
268 int rc;
269
270 rc = check_string(attr: "sysplex_name", str: buf);
271 if (rc)
272 return rc;
273
274 mutex_lock(&sclp_cpi_mutex);
275 set_string(attr: sysplex_name, value: buf);
276 mutex_unlock(lock: &sclp_cpi_mutex);
277
278 return len;
279}
280
281static struct kobj_attribute sysplex_name_attr =
282 __ATTR(sysplex_name, 0644, sysplex_name_show, sysplex_name_store);
283
284static ssize_t system_type_show(struct kobject *kobj,
285 struct kobj_attribute *attr, char *page)
286{
287 int rc;
288
289 mutex_lock(&sclp_cpi_mutex);
290 rc = snprintf(buf: page, PAGE_SIZE, fmt: "%s\n", system_type);
291 mutex_unlock(lock: &sclp_cpi_mutex);
292 return rc;
293}
294
295static ssize_t system_type_store(struct kobject *kobj,
296 struct kobj_attribute *attr,
297 const char *buf,
298 size_t len)
299{
300 int rc;
301
302 rc = check_string(attr: "system_type", str: buf);
303 if (rc)
304 return rc;
305
306 mutex_lock(&sclp_cpi_mutex);
307 set_string(attr: system_type, value: buf);
308 mutex_unlock(lock: &sclp_cpi_mutex);
309
310 return len;
311}
312
313static struct kobj_attribute system_type_attr =
314 __ATTR(system_type, 0644, system_type_show, system_type_store);
315
316static ssize_t system_level_show(struct kobject *kobj,
317 struct kobj_attribute *attr, char *page)
318{
319 unsigned long long level;
320
321 mutex_lock(&sclp_cpi_mutex);
322 level = system_level;
323 mutex_unlock(lock: &sclp_cpi_mutex);
324 return snprintf(buf: page, PAGE_SIZE, fmt: "%#018llx\n", level);
325}
326
327static ssize_t system_level_store(struct kobject *kobj,
328 struct kobj_attribute *attr,
329 const char *buf,
330 size_t len)
331{
332 unsigned long long level;
333 char *endp;
334
335 level = simple_strtoull(buf, &endp, 16);
336
337 if (endp == buf)
338 return -EINVAL;
339 if (*endp == '\n')
340 endp++;
341 if (*endp)
342 return -EINVAL;
343
344 mutex_lock(&sclp_cpi_mutex);
345 system_level = level;
346 mutex_unlock(lock: &sclp_cpi_mutex);
347 return len;
348}
349
350static struct kobj_attribute system_level_attr =
351 __ATTR(system_level, 0644, system_level_show, system_level_store);
352
353static ssize_t set_store(struct kobject *kobj,
354 struct kobj_attribute *attr,
355 const char *buf, size_t len)
356{
357 int rc;
358
359 mutex_lock(&sclp_cpi_mutex);
360 rc = cpi_req();
361 mutex_unlock(lock: &sclp_cpi_mutex);
362 if (rc)
363 return rc;
364
365 return len;
366}
367
368static struct kobj_attribute set_attr = __ATTR(set, 0200, NULL, set_store);
369
370static struct attribute *cpi_attrs[] = {
371 &system_name_attr.attr,
372 &sysplex_name_attr.attr,
373 &system_type_attr.attr,
374 &system_level_attr.attr,
375 &set_attr.attr,
376 NULL,
377};
378
379static struct attribute_group cpi_attr_group = {
380 .attrs = cpi_attrs,
381};
382
383static struct kset *cpi_kset;
384
385int sclp_cpi_set_data(const char *system, const char *sysplex, const char *type,
386 const u64 level)
387{
388 int rc;
389
390 rc = check_string(attr: "system_name", str: system);
391 if (rc)
392 return rc;
393 rc = check_string(attr: "sysplex_name", str: sysplex);
394 if (rc)
395 return rc;
396 rc = check_string(attr: "system_type", str: type);
397 if (rc)
398 return rc;
399
400 mutex_lock(&sclp_cpi_mutex);
401 set_string(attr: system_name, value: system);
402 set_string(attr: sysplex_name, value: sysplex);
403 set_string(attr: system_type, value: type);
404 system_level = level;
405
406 rc = cpi_req();
407 mutex_unlock(lock: &sclp_cpi_mutex);
408
409 return rc;
410}
411EXPORT_SYMBOL(sclp_cpi_set_data);
412
413static int __init cpi_init(void)
414{
415 int rc;
416
417 cpi_kset = kset_create_and_add(name: "cpi", NULL, parent_kobj: firmware_kobj);
418 if (!cpi_kset)
419 return -ENOMEM;
420
421 rc = sysfs_create_group(kobj: &cpi_kset->kobj, grp: &cpi_attr_group);
422 if (rc)
423 kset_unregister(kset: cpi_kset);
424
425 return rc;
426}
427
428__initcall(cpi_init);
429

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