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);