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 #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 <asm/ebcdic.h>
  25 #include <asm/sclp.h>
  26
  27 #include "sclp.h"
  28 #include "sclp_rw.h"
  29 #include "sclp_cpi_sys.h"
  30
  31 #define CPI_LENGTH_NAME 8
  32 #define CPI_LENGTH_LEVEL 16
  33
  34 static DEFINE_MUTEX(sclp_cpi_mutex);
  35
  36 struct cpi_evbuf {
  37         struct evbuf_header header;
  38         u8      id_format;
  39         u8      reserved0;
  40         u8      system_type[CPI_LENGTH_NAME];
  41         u64     reserved1;
  42         u8      system_name[CPI_LENGTH_NAME];
  43         u64     reserved2;
  44         u64     system_level;
  45         u64     reserved3;
  46         u8      sysplex_name[CPI_LENGTH_NAME];
  47         u8      reserved4[16];
  48 } __attribute__((packed));
  49
  50 struct cpi_sccb {
  51         struct sccb_header header;
  52         struct cpi_evbuf cpi_evbuf;
  53 } __attribute__((packed));
  54
  55 static struct sclp_register sclp_cpi_event = {
  56         .send_mask = EVTYP_CTLPROGIDENT_MASK,
  57 };
  58
  59 static char system_name[CPI_LENGTH_NAME + 1];
  60 static char sysplex_name[CPI_LENGTH_NAME + 1];
  61 static char system_type[CPI_LENGTH_NAME + 1];
  62 static u64 system_level;
  63
  64 static void set_data(char *field, char *data)
  65 {
  66         memset(field, ' ', CPI_LENGTH_NAME);
  67         memcpy(field, data, strlen(data));
  68         sclp_ascebc_str(field, CPI_LENGTH_NAME);
  69 }
  70
  71 static void cpi_callback(struct sclp_req *req, void *data)
  72 {
  73         struct completion *completion = data;
  74
  75         complete(completion);
  76 }
  77
  78 static struct sclp_req *cpi_prepare_req(void)
  79 {
  80         struct sclp_req *req;
  81         struct cpi_sccb *sccb;
  82         struct cpi_evbuf *evb;
  83
  84         req = kzalloc(sizeof(struct sclp_req), GFP_KERNEL);
  85         if (!req)
  86                 return ERR_PTR(-ENOMEM);
  87         sccb = (struct cpi_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
  88         if (!sccb) {
  89                 kfree(req);
  90                 return ERR_PTR(-ENOMEM);
  91         }
  92
  93         /* setup SCCB for Control-Program Identification */
  94         sccb->header.length = sizeof(struct cpi_sccb);
  95         sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
  96         sccb->cpi_evbuf.header.type = 0x0b;
  97         evb = &sccb->cpi_evbuf;
  98
  99         /* set system type */
 100         set_data(evb->system_type, system_type);
 101
 102         /* set system name */
 103         set_data(evb->system_name, system_name);
 104
 105         /* set sytem level */
 106         evb->system_level = system_level;
 107
 108         /* set sysplex name */
 109         set_data(evb->sysplex_name, sysplex_name);
 110
 111         /* prepare request data structure presented to SCLP driver */
 112         req->command = SCLP_CMDW_WRITE_EVENT_DATA;
 113         req->sccb = sccb;
 114         req->status = SCLP_REQ_FILLED;
 115         req->callback = cpi_callback;
 116         return req;
 117 }
 118
 119 static void cpi_free_req(struct sclp_req *req)
 120 {
 121         free_page((unsigned long) req->sccb);
 122         kfree(req);
 123 }
 124
 125 static int cpi_req(void)
 126 {
 127         struct completion completion;
 128         struct sclp_req *req;
 129         int rc;
 130         int response;
 131
 132         rc = sclp_register(&sclp_cpi_event);
 133         if (rc)
 134                 goto out;
 135         if (!(sclp_cpi_event.sclp_receive_mask & EVTYP_CTLPROGIDENT_MASK)) {
 136                 rc = -EOPNOTSUPP;
 137                 goto out_unregister;
 138         }
 139
 140         req = cpi_prepare_req();
 141         if (IS_ERR(req)) {
 142                 rc = PTR_ERR(req);
 143                 goto out_unregister;
 144         }
 145
 146         init_completion(&completion);
 147         req->callback_data = &completion;
 148
 149         /* Add request to sclp queue */
 150         rc = sclp_add_request(req);
 151         if (rc)
 152                 goto out_free_req;
 153
 154         wait_for_completion(&completion);
 155
 156         if (req->status != SCLP_REQ_DONE) {
 157                 pr_warning("request failed (status=0x%02x)\n",
 158                            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_warning("request failed with response code 0x%x\n",
 166                            response);
 167                 rc = -EIO;
 168         }
 169
 170 out_free_req:
 171         cpi_free_req(req);
 172
 173 out_unregister:
 174         sclp_unregister(&sclp_cpi_event);
 175
 176 out:
 177         return rc;
 178 }
 179
 180 static int check_string(const char *attr, const char *str)
 181 {
 182         size_t len;
 183         size_t i;
 184
 185         len = strlen(str);
 186
 187         if ((len > 0) && (str[len - 1] == '\n'))
 188                 len--;
 189
 190         if (len > CPI_LENGTH_NAME)
 191                 return -EINVAL;
 192
 193         for (i = 0; i < len ; i++) {
 194                 if (isalpha(str[i]) || isdigit(str[i]) ||
 195                     strchr("$@# ", str[i]))
 196                         continue;
 197                 return -EINVAL;
 198         }
 199
 200         return 0;
 201 }
 202
 203 static void set_string(char *attr, const char *value)
 204 {
 205         size_t len;
 206         size_t i;
 207
 208         len = strlen(value);
 209
 210         if ((len > 0) && (value[len - 1] == '\n'))
 211                 len--;
 212
 213         for (i = 0; i < CPI_LENGTH_NAME; i++) {
 214                 if (i < len)
 215                         attr[i] = toupper(value[i]);
 216                 else
 217                         attr[i] = ' ';
 218         }
 219 }
 220
 221 static ssize_t system_name_show(struct kobject *kobj,
 222                                 struct kobj_attribute *attr, char *page)
 223 {
 224         int rc;
 225
 226         mutex_lock(&sclp_cpi_mutex);
 227         rc = snprintf(page, PAGE_SIZE, "%s\n", system_name);
 228         mutex_unlock(&sclp_cpi_mutex);
 229         return rc;
 230 }
 231
 232 static ssize_t system_name_store(struct kobject *kobj,
 233                                  struct kobj_attribute *attr,
 234                                  const char *buf,
 235         size_t len)
 236 {
 237         int rc;
 238
 239         rc = check_string("system_name", buf);
 240         if (rc)
 241                 return rc;
 242
 243         mutex_lock(&sclp_cpi_mutex);
 244         set_string(system_name, buf);
 245         mutex_unlock(&sclp_cpi_mutex);
 246
 247         return len;
 248 }
 249
 250 static struct kobj_attribute system_name_attr =
 251         __ATTR(system_name, 0644, system_name_show, system_name_store);
 252
 253 static ssize_t sysplex_name_show(struct kobject *kobj,
 254                                  struct kobj_attribute *attr, char *page)
 255 {
 256         int rc;
 257
 258         mutex_lock(&sclp_cpi_mutex);
 259         rc = snprintf(page, PAGE_SIZE, "%s\n", sysplex_name);
 260         mutex_unlock(&sclp_cpi_mutex);
 261         return rc;
 262 }
 263
 264 static ssize_t sysplex_name_store(struct kobject *kobj,
 265                                   struct kobj_attribute *attr,
 266                                   const char *buf,
 267         size_t len)
 268 {
 269         int rc;
 270
 271         rc = check_string("sysplex_name", buf);
 272         if (rc)
 273                 return rc;
 274
 275         mutex_lock(&sclp_cpi_mutex);
 276         set_string(sysplex_name, buf);
 277         mutex_unlock(&sclp_cpi_mutex);
 278
 279         return len;
 280 }
 281
 282 static struct kobj_attribute sysplex_name_attr =
 283         __ATTR(sysplex_name, 0644, sysplex_name_show, sysplex_name_store);
 284
 285 static ssize_t system_type_show(struct kobject *kobj,
 286                                 struct kobj_attribute *attr, char *page)
 287 {
 288         int rc;
 289
 290         mutex_lock(&sclp_cpi_mutex);
 291         rc = snprintf(page, PAGE_SIZE, "%s\n", system_type);
 292         mutex_unlock(&sclp_cpi_mutex);
 293         return rc;
 294 }
 295
 296 static ssize_t system_type_store(struct kobject *kobj,
 297                                  struct kobj_attribute *attr,
 298                                  const char *buf,
 299         size_t len)
 300 {
 301         int rc;
 302
 303         rc = check_string("system_type", buf);
 304         if (rc)
 305                 return rc;
 306
 307         mutex_lock(&sclp_cpi_mutex);
 308         set_string(system_type, buf);
 309         mutex_unlock(&sclp_cpi_mutex);
 310
 311         return len;
 312 }
 313
 314 static struct kobj_attribute system_type_attr =
 315         __ATTR(system_type, 0644, system_type_show, system_type_store);
 316
 317 static ssize_t system_level_show(struct kobject *kobj,
 318                                  struct kobj_attribute *attr, char *page)
 319 {
 320         unsigned long long level;
 321
 322         mutex_lock(&sclp_cpi_mutex);
 323         level = system_level;
 324         mutex_unlock(&sclp_cpi_mutex);
 325         return snprintf(page, PAGE_SIZE, "%#018llx\n", level);
 326 }
 327
 328 static ssize_t system_level_store(struct kobject *kobj,
 329                                   struct kobj_attribute *attr,
 330                                   const char *buf,
 331         size_t len)
 332 {
 333         unsigned long long level;
 334         char *endp;
 335
 336         level = simple_strtoull(buf, &endp, 16);
 337
 338         if (endp == buf)
 339                 return -EINVAL;
 340         if (*endp == '\n')
 341                 endp++;
 342         if (*endp)
 343                 return -EINVAL;
 344
 345         mutex_lock(&sclp_cpi_mutex);
 346         system_level = level;
 347         mutex_unlock(&sclp_cpi_mutex);
 348         return len;
 349 }
 350
 351 static struct kobj_attribute system_level_attr =
 352         __ATTR(system_level, 0644, system_level_show, system_level_store);
 353
 354 static ssize_t set_store(struct kobject *kobj,
 355                          struct kobj_attribute *attr,
 356                          const char *buf, size_t len)
 357 {
 358         int rc;
 359
 360         mutex_lock(&sclp_cpi_mutex);
 361         rc = cpi_req();
 362         mutex_unlock(&sclp_cpi_mutex);
 363         if (rc)
 364                 return rc;
 365
 366         return len;
 367 }
 368
 369 static struct kobj_attribute set_attr = __ATTR(set, 0200, NULL, set_store);
 370
 371 static struct attribute *cpi_attrs[] = {
 372         &system_name_attr.attr,
 373         &sysplex_name_attr.attr,
 374         &system_type_attr.attr,
 375         &system_level_attr.attr,
 376         &set_attr.attr,
 377         NULL,
 378 };
 379
 380 static struct attribute_group cpi_attr_group = {
 381         .attrs = cpi_attrs,
 382 };
 383
 384 static struct kset *cpi_kset;
 385
 386 int sclp_cpi_set_data(const char *system, const char *sysplex, const char *type,
 387                       const u64 level)
 388 {
 389         int rc;
 390
 391         rc = check_string("system_name", system);
 392         if (rc)
 393                 return rc;
 394         rc = check_string("sysplex_name", sysplex);
 395         if (rc)
 396                 return rc;
 397         rc = check_string("system_type", type);
 398         if (rc)
 399                 return rc;
 400
 401         mutex_lock(&sclp_cpi_mutex);
 402         set_string(system_name, system);
 403         set_string(sysplex_name, sysplex);
 404         set_string(system_type, type);
 405         system_level = level;
 406
 407         rc = cpi_req();
 408         mutex_unlock(&sclp_cpi_mutex);
 409
 410         return rc;
 411 }
 412 EXPORT_SYMBOL(sclp_cpi_set_data);
 413
 414 static int __init cpi_init(void)
 415 {
 416         int rc;
 417
 418         cpi_kset = kset_create_and_add("cpi", NULL, firmware_kobj);
 419         if (!cpi_kset)
 420                 return -ENOMEM;
 421
 422         rc = sysfs_create_group(&cpi_kset->kobj, &cpi_attr_group);
 423         if (rc)
 424                 kset_unregister(cpi_kset);
 425
 426         return rc;
 427 }
 428
 429 __initcall(cpi_init);