Merge branch 'for_linus' of git://git.infradead.org/~dedekind/ubifs-2.6
[linux-2.6] / drivers / s390 / char / sclp_cpi_sys.c
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);