xref: /openbmc/linux/drivers/s390/char/sclp_cpi_sys.c (revision 384740dc)
1 /*
2  *  drivers/s390/char/sclp_cpi_sys.c
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 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/stat.h>
13 #include <linux/device.h>
14 #include <linux/string.h>
15 #include <linux/ctype.h>
16 #include <linux/kmod.h>
17 #include <linux/timer.h>
18 #include <linux/err.h>
19 #include <linux/slab.h>
20 #include <linux/completion.h>
21 #include <asm/ebcdic.h>
22 #include <asm/sclp.h>
23 #include "sclp.h"
24 #include "sclp_rw.h"
25 #include "sclp_cpi_sys.h"
26 
27 #define CPI_LENGTH_NAME 8
28 #define CPI_LENGTH_LEVEL 16
29 
30 static DEFINE_MUTEX(sclp_cpi_mutex);
31 
32 struct cpi_evbuf {
33 	struct evbuf_header header;
34 	u8	id_format;
35 	u8	reserved0;
36 	u8	system_type[CPI_LENGTH_NAME];
37 	u64	reserved1;
38 	u8	system_name[CPI_LENGTH_NAME];
39 	u64	reserved2;
40 	u64	system_level;
41 	u64	reserved3;
42 	u8	sysplex_name[CPI_LENGTH_NAME];
43 	u8	reserved4[16];
44 } __attribute__((packed));
45 
46 struct cpi_sccb {
47 	struct sccb_header header;
48 	struct cpi_evbuf cpi_evbuf;
49 } __attribute__((packed));
50 
51 static struct sclp_register sclp_cpi_event = {
52 	.send_mask = EVTYP_CTLPROGIDENT_MASK,
53 };
54 
55 static char system_name[CPI_LENGTH_NAME + 1];
56 static char sysplex_name[CPI_LENGTH_NAME + 1];
57 static char system_type[CPI_LENGTH_NAME + 1];
58 static u64 system_level;
59 
60 static void set_data(char *field, char *data)
61 {
62 	memset(field, ' ', CPI_LENGTH_NAME);
63 	memcpy(field, data, strlen(data));
64 	sclp_ascebc_str(field, CPI_LENGTH_NAME);
65 }
66 
67 static void cpi_callback(struct sclp_req *req, void *data)
68 {
69 	struct completion *completion = data;
70 
71 	complete(completion);
72 }
73 
74 static struct sclp_req *cpi_prepare_req(void)
75 {
76 	struct sclp_req *req;
77 	struct cpi_sccb *sccb;
78 	struct cpi_evbuf *evb;
79 
80 	req = kzalloc(sizeof(struct sclp_req), GFP_KERNEL);
81 	if (!req)
82 		return ERR_PTR(-ENOMEM);
83 	sccb = (struct cpi_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
84 	if (!sccb) {
85 		kfree(req);
86 		return ERR_PTR(-ENOMEM);
87 	}
88 
89 	/* setup SCCB for Control-Program Identification */
90 	sccb->header.length = sizeof(struct cpi_sccb);
91 	sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
92 	sccb->cpi_evbuf.header.type = 0x0b;
93 	evb = &sccb->cpi_evbuf;
94 
95 	/* set system type */
96 	set_data(evb->system_type, system_type);
97 
98 	/* set system name */
99 	set_data(evb->system_name, system_name);
100 
101 	/* set sytem level */
102 	evb->system_level = system_level;
103 
104 	/* set sysplex name */
105 	set_data(evb->sysplex_name, sysplex_name);
106 
107 	/* prepare request data structure presented to SCLP driver */
108 	req->command = SCLP_CMDW_WRITE_EVENT_DATA;
109 	req->sccb = sccb;
110 	req->status = SCLP_REQ_FILLED;
111 	req->callback = cpi_callback;
112 	return req;
113 }
114 
115 static void cpi_free_req(struct sclp_req *req)
116 {
117 	free_page((unsigned long) req->sccb);
118 	kfree(req);
119 }
120 
121 static int cpi_req(void)
122 {
123 	struct completion completion;
124 	struct sclp_req *req;
125 	int rc;
126 	int response;
127 
128 	rc = sclp_register(&sclp_cpi_event);
129 	if (rc)
130 		goto out;
131 	if (!(sclp_cpi_event.sclp_receive_mask & EVTYP_CTLPROGIDENT_MASK)) {
132 		rc = -EOPNOTSUPP;
133 		goto out_unregister;
134 	}
135 
136 	req = cpi_prepare_req();
137 	if (IS_ERR(req)) {
138 		rc = PTR_ERR(req);
139 		goto out_unregister;
140 	}
141 
142 	init_completion(&completion);
143 	req->callback_data = &completion;
144 
145 	/* Add request to sclp queue */
146 	rc = sclp_add_request(req);
147 	if (rc)
148 		goto out_free_req;
149 
150 	wait_for_completion(&completion);
151 
152 	if (req->status != SCLP_REQ_DONE) {
153 		printk(KERN_WARNING "cpi: request failed (status=0x%02x)\n",
154 			req->status);
155 		rc = -EIO;
156 		goto out_free_req;
157 	}
158 
159 	response = ((struct cpi_sccb *) req->sccb)->header.response_code;
160 	if (response != 0x0020) {
161 		printk(KERN_WARNING "cpi: failed with "
162 			"response code 0x%x\n", response);
163 		rc = -EIO;
164 	}
165 
166 out_free_req:
167 	cpi_free_req(req);
168 
169 out_unregister:
170 	sclp_unregister(&sclp_cpi_event);
171 
172 out:
173 	return rc;
174 }
175 
176 static int check_string(const char *attr, const char *str)
177 {
178 	size_t len;
179 	size_t i;
180 
181 	len = strlen(str);
182 
183 	if ((len > 0) && (str[len - 1] == '\n'))
184 		len--;
185 
186 	if (len > CPI_LENGTH_NAME)
187 		return -EINVAL;
188 
189 	for (i = 0; i < len ; i++) {
190 		if (isalpha(str[i]) || isdigit(str[i]) ||
191 		    strchr("$@# ", str[i]))
192 			continue;
193 		return -EINVAL;
194 	}
195 
196 	return 0;
197 }
198 
199 static void set_string(char *attr, const char *value)
200 {
201 	size_t len;
202 	size_t i;
203 
204 	len = strlen(value);
205 
206 	if ((len > 0) && (value[len - 1] == '\n'))
207 		len--;
208 
209 	for (i = 0; i < CPI_LENGTH_NAME; i++) {
210 		if (i < len)
211 			attr[i] = toupper(value[i]);
212 		else
213 			attr[i] = ' ';
214 	}
215 }
216 
217 static ssize_t system_name_show(struct kobject *kobj,
218 				struct kobj_attribute *attr, char *page)
219 {
220 	int rc;
221 
222 	mutex_lock(&sclp_cpi_mutex);
223 	rc = snprintf(page, PAGE_SIZE, "%s\n", system_name);
224 	mutex_unlock(&sclp_cpi_mutex);
225 	return rc;
226 }
227 
228 static ssize_t system_name_store(struct kobject *kobj,
229 				 struct kobj_attribute *attr,
230 				 const char *buf,
231 	size_t len)
232 {
233 	int rc;
234 
235 	rc = check_string("system_name", buf);
236 	if (rc)
237 		return rc;
238 
239 	mutex_lock(&sclp_cpi_mutex);
240 	set_string(system_name, buf);
241 	mutex_unlock(&sclp_cpi_mutex);
242 
243 	return len;
244 }
245 
246 static struct kobj_attribute system_name_attr =
247 	__ATTR(system_name, 0644, system_name_show, system_name_store);
248 
249 static ssize_t sysplex_name_show(struct kobject *kobj,
250 				 struct kobj_attribute *attr, char *page)
251 {
252 	int rc;
253 
254 	mutex_lock(&sclp_cpi_mutex);
255 	rc = snprintf(page, PAGE_SIZE, "%s\n", sysplex_name);
256 	mutex_unlock(&sclp_cpi_mutex);
257 	return rc;
258 }
259 
260 static ssize_t sysplex_name_store(struct kobject *kobj,
261 				  struct kobj_attribute *attr,
262 				  const char *buf,
263 	size_t len)
264 {
265 	int rc;
266 
267 	rc = check_string("sysplex_name", buf);
268 	if (rc)
269 		return rc;
270 
271 	mutex_lock(&sclp_cpi_mutex);
272 	set_string(sysplex_name, buf);
273 	mutex_unlock(&sclp_cpi_mutex);
274 
275 	return len;
276 }
277 
278 static struct kobj_attribute sysplex_name_attr =
279 	__ATTR(sysplex_name, 0644, sysplex_name_show, sysplex_name_store);
280 
281 static ssize_t system_type_show(struct kobject *kobj,
282 				struct kobj_attribute *attr, char *page)
283 {
284 	int rc;
285 
286 	mutex_lock(&sclp_cpi_mutex);
287 	rc = snprintf(page, PAGE_SIZE, "%s\n", system_type);
288 	mutex_unlock(&sclp_cpi_mutex);
289 	return rc;
290 }
291 
292 static ssize_t system_type_store(struct kobject *kobj,
293 				 struct kobj_attribute *attr,
294 				 const char *buf,
295 	size_t len)
296 {
297 	int rc;
298 
299 	rc = check_string("system_type", buf);
300 	if (rc)
301 		return rc;
302 
303 	mutex_lock(&sclp_cpi_mutex);
304 	set_string(system_type, buf);
305 	mutex_unlock(&sclp_cpi_mutex);
306 
307 	return len;
308 }
309 
310 static struct kobj_attribute system_type_attr =
311 	__ATTR(system_type, 0644, system_type_show, system_type_store);
312 
313 static ssize_t system_level_show(struct kobject *kobj,
314 				 struct kobj_attribute *attr, char *page)
315 {
316 	unsigned long long level;
317 
318 	mutex_lock(&sclp_cpi_mutex);
319 	level = system_level;
320 	mutex_unlock(&sclp_cpi_mutex);
321 	return snprintf(page, PAGE_SIZE, "%#018llx\n", level);
322 }
323 
324 static ssize_t system_level_store(struct kobject *kobj,
325 				  struct kobj_attribute *attr,
326 				  const char *buf,
327 	size_t len)
328 {
329 	unsigned long long level;
330 	char *endp;
331 
332 	level = simple_strtoull(buf, &endp, 16);
333 
334 	if (endp == buf)
335 		return -EINVAL;
336 	if (*endp == '\n')
337 		endp++;
338 	if (*endp)
339 		return -EINVAL;
340 
341 	mutex_lock(&sclp_cpi_mutex);
342 	system_level = level;
343 	mutex_unlock(&sclp_cpi_mutex);
344 	return len;
345 }
346 
347 static struct kobj_attribute system_level_attr =
348 	__ATTR(system_level, 0644, system_level_show, system_level_store);
349 
350 static ssize_t set_store(struct kobject *kobj,
351 			 struct kobj_attribute *attr,
352 			 const char *buf, size_t len)
353 {
354 	int rc;
355 
356 	mutex_lock(&sclp_cpi_mutex);
357 	rc = cpi_req();
358 	mutex_unlock(&sclp_cpi_mutex);
359 	if (rc)
360 		return rc;
361 
362 	return len;
363 }
364 
365 static struct kobj_attribute set_attr = __ATTR(set, 0200, NULL, set_store);
366 
367 static struct attribute *cpi_attrs[] = {
368 	&system_name_attr.attr,
369 	&sysplex_name_attr.attr,
370 	&system_type_attr.attr,
371 	&system_level_attr.attr,
372 	&set_attr.attr,
373 	NULL,
374 };
375 
376 static struct attribute_group cpi_attr_group = {
377 	.attrs = cpi_attrs,
378 };
379 
380 static struct kset *cpi_kset;
381 
382 int sclp_cpi_set_data(const char *system, const char *sysplex, const char *type,
383 		      const u64 level)
384 {
385 	int rc;
386 
387 	rc = check_string("system_name", system);
388 	if (rc)
389 		return rc;
390 	rc = check_string("sysplex_name", sysplex);
391 	if (rc)
392 		return rc;
393 	rc = check_string("system_type", type);
394 	if (rc)
395 		return rc;
396 
397 	mutex_lock(&sclp_cpi_mutex);
398 	set_string(system_name, system);
399 	set_string(sysplex_name, sysplex);
400 	set_string(system_type, type);
401 	system_level = level;
402 
403 	rc = cpi_req();
404 	mutex_unlock(&sclp_cpi_mutex);
405 
406 	return rc;
407 }
408 EXPORT_SYMBOL(sclp_cpi_set_data);
409 
410 static int __init cpi_init(void)
411 {
412 	int rc;
413 
414 	cpi_kset = kset_create_and_add("cpi", NULL, firmware_kobj);
415 	if (!cpi_kset)
416 		return -ENOMEM;
417 
418 	rc = sysfs_create_group(&cpi_kset->kobj, &cpi_attr_group);
419 	if (rc)
420 		kset_unregister(cpi_kset);
421 
422 	return rc;
423 }
424 
425 __initcall(cpi_init);
426