drivers/s390/char/sclp_cpi.c

   1 /*
   2  * Author: Martin Peschke <mpeschke@de.ibm.com>
   3  * Copyright (C) 2001 IBM Entwicklung GmbH, IBM Corporation
   4  *
   5  * SCLP Control-Program Identification.
   6  */
   7
   8 #include <linux/config.h>
   9 #include <linux/version.h>
  10 #include <linux/kmod.h>
  11 #include <linux/module.h>
  12 #include <linux/moduleparam.h>
  13 #include <linux/init.h>
  14 #include <linux/timer.h>
  15 #include <linux/string.h>
  16 #include <linux/err.h>
  17 #include <linux/slab.h>
  18 #include <asm/ebcdic.h>
  19 #include <asm/semaphore.h>
  20
  21 #include "sclp.h"
  22 #include "sclp_rw.h"
  23
  24 #define CPI_LENGTH_SYSTEM_TYPE  8
  25 #define CPI_LENGTH_SYSTEM_NAME  8
  26 #define CPI_LENGTH_SYSPLEX_NAME 8
  27
  28 struct cpi_evbuf {
  29         struct evbuf_header header;
  30         u8      id_format;
  31         u8      reserved0;
  32         u8      system_type[CPI_LENGTH_SYSTEM_TYPE];
  33         u64     reserved1;
  34         u8      system_name[CPI_LENGTH_SYSTEM_NAME];
  35         u64     reserved2;
  36         u64     system_level;
  37         u64     reserved3;
  38         u8      sysplex_name[CPI_LENGTH_SYSPLEX_NAME];
  39         u8      reserved4[16];
  40 } __attribute__((packed));
  41
  42 struct cpi_sccb {
  43         struct sccb_header header;
  44         struct cpi_evbuf cpi_evbuf;
  45 } __attribute__((packed));
  46
  47 /* Event type structure for write message and write priority message */
  48 static struct sclp_register sclp_cpi_event =
  49 {
  50         .send_mask = EvTyp_CtlProgIdent_Mask
  51 };
  52
  53 MODULE_AUTHOR(
  54         "Martin Peschke, IBM Deutschland Entwicklung GmbH "
  55         "<mpeschke@de.ibm.com>");
  56
  57 MODULE_DESCRIPTION(
  58         "identify this operating system instance to the S/390 "
  59         "or zSeries hardware");
  60
  61 static char *system_name = NULL;
  62 module_param(system_name, charp, 0);
  63 MODULE_PARM_DESC(system_name, "e.g. hostname - max. 8 characters");
  64
  65 static char *sysplex_name = NULL;
  66 #ifdef ALLOW_SYSPLEX_NAME
  67 module_param(sysplex_name, charp, 0);
  68 MODULE_PARM_DESC(sysplex_name, "if applicable - max. 8 characters");
  69 #endif
  70
  71 /* use default value for this field (as well as for system level) */
  72 static char *system_type = "LINUX";
  73
  74 static int
  75 cpi_check_parms(void)
  76 {
  77         /* reject if no system type specified */
  78         if (!system_type) {
  79                 printk("cpi: bug: no system type specified\n");
  80                 return -EINVAL;
  81         }
  82
  83         /* reject if system type larger than 8 characters */
  84         if (strlen(system_type) > CPI_LENGTH_SYSTEM_NAME) {
  85                 printk("cpi: bug: system type has length of %li characters - "
  86                        "only %i characters supported\n",
  87                        strlen(system_type), CPI_LENGTH_SYSTEM_TYPE);
  88                 return -EINVAL;
  89         }
  90
  91         /* reject if no system name specified */
  92         if (!system_name) {
  93                 printk("cpi: no system name specified\n");
  94                 return -EINVAL;
  95         }
  96
  97         /* reject if system name larger than 8 characters */
  98         if (strlen(system_name) > CPI_LENGTH_SYSTEM_NAME) {
  99                 printk("cpi: system name has length of %li characters - "
 100                        "only %i characters supported\n",
 101                        strlen(system_name), CPI_LENGTH_SYSTEM_NAME);
 102                 return -EINVAL;
 103         }
 104
 105         /* reject if specified sysplex name larger than 8 characters */
 106         if (sysplex_name && strlen(sysplex_name) > CPI_LENGTH_SYSPLEX_NAME) {
 107                 printk("cpi: sysplex name has length of %li characters"
 108                        " - only %i characters supported\n",
 109                        strlen(sysplex_name), CPI_LENGTH_SYSPLEX_NAME);
 110                 return -EINVAL;
 111         }
 112         return 0;
 113 }
 114
 115 static void
 116 cpi_callback(struct sclp_req *req, void *data)
 117 {
 118         struct semaphore *sem;
 119
 120         sem = (struct semaphore *) data;
 121         up(sem);
 122 }
 123
 124 static struct sclp_req *
 125 cpi_prepare_req(void)
 126 {
 127         struct sclp_req *req;
 128         struct cpi_sccb *sccb;
 129         struct cpi_evbuf *evb;
 130
 131         req = (struct sclp_req *) kmalloc(sizeof(struct sclp_req), GFP_KERNEL);
 132         if (req == NULL)
 133                 return ERR_PTR(-ENOMEM);
 134         sccb = (struct cpi_sccb *) __get_free_page(GFP_KERNEL | GFP_DMA);
 135         if (sccb == NULL) {
 136                 kfree(req);
 137                 return ERR_PTR(-ENOMEM);
 138         }
 139         memset(sccb, 0, sizeof(struct cpi_sccb));
 140
 141         /* setup SCCB for Control-Program Identification */
 142         sccb->header.length = sizeof(struct cpi_sccb);
 143         sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
 144         sccb->cpi_evbuf.header.type = 0x0B;
 145         evb = &sccb->cpi_evbuf;
 146
 147         /* set system type */
 148         memset(evb->system_type, ' ', CPI_LENGTH_SYSTEM_TYPE);
 149         memcpy(evb->system_type, system_type, strlen(system_type));
 150         sclp_ascebc_str(evb->system_type, CPI_LENGTH_SYSTEM_TYPE);
 151         EBC_TOUPPER(evb->system_type, CPI_LENGTH_SYSTEM_TYPE);
 152
 153         /* set system name */
 154         memset(evb->system_name, ' ', CPI_LENGTH_SYSTEM_NAME);
 155         memcpy(evb->system_name, system_name, strlen(system_name));
 156         sclp_ascebc_str(evb->system_name, CPI_LENGTH_SYSTEM_NAME);
 157         EBC_TOUPPER(evb->system_name, CPI_LENGTH_SYSTEM_NAME);
 158
 159         /* set sytem level */
 160         evb->system_level = LINUX_VERSION_CODE;
 161
 162         /* set sysplex name */
 163         if (sysplex_name) {
 164                 memset(evb->sysplex_name, ' ', CPI_LENGTH_SYSPLEX_NAME);
 165                 memcpy(evb->sysplex_name, sysplex_name, strlen(sysplex_name));
 166                 sclp_ascebc_str(evb->sysplex_name, CPI_LENGTH_SYSPLEX_NAME);
 167                 EBC_TOUPPER(evb->sysplex_name, CPI_LENGTH_SYSPLEX_NAME);
 168         }
 169
 170         /* prepare request data structure presented to SCLP driver */
 171         req->command = SCLP_CMDW_WRITEDATA;
 172         req->sccb = sccb;
 173         req->status = SCLP_REQ_FILLED;
 174         req->callback = cpi_callback;
 175         return req;
 176 }
 177
 178 static void
 179 cpi_free_req(struct sclp_req *req)
 180 {
 181         free_page((unsigned long) req->sccb);
 182         kfree(req);
 183 }
 184
 185 static int __init
 186 cpi_module_init(void)
 187 {
 188         struct semaphore sem;
 189         struct sclp_req *req;
 190         int rc;
 191
 192         rc = cpi_check_parms();
 193         if (rc)
 194                 return rc;
 195
 196         rc = sclp_register(&sclp_cpi_event);
 197         if (rc) {
 198                 /* could not register sclp event. Die. */
 199                 printk("cpi: could not register to hardware console.\n");
 200                 return -EINVAL;
 201         }
 202         if (!(sclp_cpi_event.sclp_send_mask & EvTyp_CtlProgIdent_Mask)) {
 203                 printk("cpi: no control program identification support\n");
 204                 sclp_unregister(&sclp_cpi_event);
 205                 return -ENOTSUPP;
 206         }
 207
 208         req = cpi_prepare_req();
 209         if (IS_ERR(req)) {
 210                 printk("cpi: couldn't allocate request\n");
 211                 sclp_unregister(&sclp_cpi_event);
 212                 return PTR_ERR(req);
 213         }
 214
 215         /* Prepare semaphore */
 216         sema_init(&sem, 0);
 217         req->callback_data = &sem;
 218         /* Add request to sclp queue */
 219         sclp_add_request(req);
 220         /* make "insmod" sleep until callback arrives */
 221         down(&sem);
 222
 223         rc = ((struct cpi_sccb *) req->sccb)->header.response_code;
 224         if (rc != 0x0020) {
 225                 printk("cpi: failed with response code 0x%x\n", rc);
 226                 rc = -ECOMM;
 227         } else
 228                 rc = 0;
 229
 230         cpi_free_req(req);
 231         sclp_unregister(&sclp_cpi_event);
 232
 233         return rc;
 234 }
 235
 236
 237 static void __exit cpi_module_exit(void)
 238 {
 239 }
 240
 241
 242 /* declare driver module init/cleanup functions */
 243 module_init(cpi_module_init);
 244 module_exit(cpi_module_exit);
 245