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/version.h>
   9 #include <linux/kmod.h>
  10 #include <linux/module.h>
  11 #include <linux/moduleparam.h>
  12 #include <linux/init.h>
  13 #include <linux/timer.h>
  14 #include <linux/string.h>
  15 #include <linux/err.h>
  16 #include <linux/slab.h>
  17 #include <asm/ebcdic.h>
  18 #include <asm/semaphore.h>
  19
  20 #include "sclp.h"
  21 #include "sclp_rw.h"
  22
  23 #define CPI_LENGTH_SYSTEM_TYPE  8
  24 #define CPI_LENGTH_SYSTEM_NAME  8
  25 #define CPI_LENGTH_SYSPLEX_NAME 8
  26
  27 struct cpi_evbuf {
  28         struct evbuf_header header;
  29         u8      id_format;
  30         u8      reserved0;
  31         u8      system_type[CPI_LENGTH_SYSTEM_TYPE];
  32         u64     reserved1;
  33         u8      system_name[CPI_LENGTH_SYSTEM_NAME];
  34         u64     reserved2;
  35         u64     system_level;
  36         u64     reserved3;
  37         u8      sysplex_name[CPI_LENGTH_SYSPLEX_NAME];
  38         u8      reserved4[16];
  39 } __attribute__((packed));
  40
  41 struct cpi_sccb {
  42         struct sccb_header header;
  43         struct cpi_evbuf cpi_evbuf;
  44 } __attribute__((packed));
  45
  46 /* Event type structure for write message and write priority message */
  47 static struct sclp_register sclp_cpi_event =
  48 {
  49         .send_mask = EVTYP_CTLPROGIDENT_MASK
  50 };
  51
  52 MODULE_LICENSE("GPL");
  53
  54 MODULE_AUTHOR(
  55         "Martin Peschke, IBM Deutschland Entwicklung GmbH "
  56         "<mpeschke@de.ibm.com>");
  57
  58 MODULE_DESCRIPTION(
  59         "identify this operating system instance to the S/390 "
  60         "or zSeries hardware");
  61
  62 static char *system_name = NULL;
  63 module_param(system_name, charp, 0);
  64 MODULE_PARM_DESC(system_name, "e.g. hostname - max. 8 characters");
  65
  66 static char *sysplex_name = NULL;
  67 #ifdef ALLOW_SYSPLEX_NAME
  68 module_param(sysplex_name, charp, 0);
  69 MODULE_PARM_DESC(sysplex_name, "if applicable - max. 8 characters");
  70 #endif
  71
  72 /* use default value for this field (as well as for system level) */
  73 static char *system_type = "LINUX";
  74
  75 static int
  76 cpi_check_parms(void)
  77 {
  78         /* reject if no system type specified */
  79         if (!system_type) {
  80                 printk("cpi: bug: no system type specified\n");
  81                 return -EINVAL;
  82         }
  83
  84         /* reject if system type larger than 8 characters */
  85         if (strlen(system_type) > CPI_LENGTH_SYSTEM_NAME) {
  86                 printk("cpi: bug: system type has length of %li characters - "
  87                        "only %i characters supported\n",
  88                        strlen(system_type), CPI_LENGTH_SYSTEM_TYPE);
  89                 return -EINVAL;
  90         }
  91
  92         /* reject if no system name specified */
  93         if (!system_name) {
  94                 printk("cpi: no system name specified\n");
  95                 return -EINVAL;
  96         }
  97
  98         /* reject if system name larger than 8 characters */
  99         if (strlen(system_name) > CPI_LENGTH_SYSTEM_NAME) {
 100                 printk("cpi: system name has length of %li characters - "
 101                        "only %i characters supported\n",
 102                        strlen(system_name), CPI_LENGTH_SYSTEM_NAME);
 103                 return -EINVAL;
 104         }
 105
 106         /* reject if specified sysplex name larger than 8 characters */
 107         if (sysplex_name && strlen(sysplex_name) > CPI_LENGTH_SYSPLEX_NAME) {
 108                 printk("cpi: sysplex name has length of %li characters"
 109                        " - only %i characters supported\n",
 110                        strlen(sysplex_name), CPI_LENGTH_SYSPLEX_NAME);
 111                 return -EINVAL;
 112         }
 113         return 0;
 114 }
 115
 116 static void
 117 cpi_callback(struct sclp_req *req, void *data)
 118 {
 119         struct semaphore *sem;
 120
 121         sem = (struct semaphore *) data;
 122         up(sem);
 123 }
 124
 125 static struct sclp_req *
 126 cpi_prepare_req(void)
 127 {
 128         struct sclp_req *req;
 129         struct cpi_sccb *sccb;
 130         struct cpi_evbuf *evb;
 131
 132         req = kmalloc(sizeof(struct sclp_req), GFP_KERNEL);
 133         if (req == NULL)
 134                 return ERR_PTR(-ENOMEM);
 135         sccb = (struct cpi_sccb *) __get_free_page(GFP_KERNEL | GFP_DMA);
 136         if (sccb == NULL) {
 137                 kfree(req);
 138                 return ERR_PTR(-ENOMEM);
 139         }
 140         memset(sccb, 0, sizeof(struct cpi_sccb));
 141
 142         /* setup SCCB for Control-Program Identification */
 143         sccb->header.length = sizeof(struct cpi_sccb);
 144         sccb->cpi_evbuf.header.length = sizeof(struct cpi_evbuf);
 145         sccb->cpi_evbuf.header.type = 0x0B;
 146         evb = &sccb->cpi_evbuf;
 147
 148         /* set system type */
 149         memset(evb->system_type, ' ', CPI_LENGTH_SYSTEM_TYPE);
 150         memcpy(evb->system_type, system_type, strlen(system_type));
 151         sclp_ascebc_str(evb->system_type, CPI_LENGTH_SYSTEM_TYPE);
 152         EBC_TOUPPER(evb->system_type, CPI_LENGTH_SYSTEM_TYPE);
 153
 154         /* set system name */
 155         memset(evb->system_name, ' ', CPI_LENGTH_SYSTEM_NAME);
 156         memcpy(evb->system_name, system_name, strlen(system_name));
 157         sclp_ascebc_str(evb->system_name, CPI_LENGTH_SYSTEM_NAME);
 158         EBC_TOUPPER(evb->system_name, CPI_LENGTH_SYSTEM_NAME);
 159
 160         /* set system level */
 161         evb->system_level = LINUX_VERSION_CODE;
 162
 163         /* set sysplex name */
 164         if (sysplex_name) {
 165                 memset(evb->sysplex_name, ' ', CPI_LENGTH_SYSPLEX_NAME);
 166                 memcpy(evb->sysplex_name, sysplex_name, strlen(sysplex_name));
 167                 sclp_ascebc_str(evb->sysplex_name, CPI_LENGTH_SYSPLEX_NAME);
 168                 EBC_TOUPPER(evb->sysplex_name, CPI_LENGTH_SYSPLEX_NAME);
 169         }
 170
 171         /* prepare request data structure presented to SCLP driver */
 172         req->command = SCLP_CMDW_WRITE_EVENT_DATA;
 173         req->sccb = sccb;
 174         req->status = SCLP_REQ_FILLED;
 175         req->callback = cpi_callback;
 176         return req;
 177 }
 178
 179 static void
 180 cpi_free_req(struct sclp_req *req)
 181 {
 182         free_page((unsigned long) req->sccb);
 183         kfree(req);
 184 }
 185
 186 static int __init
 187 cpi_module_init(void)
 188 {
 189         struct semaphore sem;
 190         struct sclp_req *req;
 191         int rc;
 192
 193         rc = cpi_check_parms();
 194         if (rc)
 195                 return rc;
 196
 197         rc = sclp_register(&sclp_cpi_event);
 198         if (rc) {
 199                 /* could not register sclp event. Die. */
 200                 printk(KERN_WARNING "cpi: could not register to hardware "
 201                        "console.\n");
 202                 return -EINVAL;
 203         }
 204         if (!(sclp_cpi_event.sclp_send_mask & EVTYP_CTLPROGIDENT_MASK)) {
 205                 printk(KERN_WARNING "cpi: no control program identification "
 206                        "support\n");
 207                 sclp_unregister(&sclp_cpi_event);
 208                 return -EOPNOTSUPP;
 209         }
 210
 211         req = cpi_prepare_req();
 212         if (IS_ERR(req)) {
 213                 printk(KERN_WARNING "cpi: couldn't allocate request\n");
 214                 sclp_unregister(&sclp_cpi_event);
 215                 return PTR_ERR(req);
 216         }
 217
 218         /* Prepare semaphore */
 219         sema_init(&sem, 0);
 220         req->callback_data = &sem;
 221         /* Add request to sclp queue */
 222         rc = sclp_add_request(req);
 223         if (rc) {
 224                 printk(KERN_WARNING "cpi: could not start request\n");
 225                 cpi_free_req(req);
 226                 sclp_unregister(&sclp_cpi_event);
 227                 return rc;
 228         }
 229         /* make "insmod" sleep until callback arrives */
 230         down(&sem);
 231
 232         rc = ((struct cpi_sccb *) req->sccb)->header.response_code;
 233         if (rc != 0x0020) {
 234                 printk(KERN_WARNING "cpi: failed with response code 0x%x\n",
 235                        rc);
 236                 rc = -ECOMM;
 237         } else
 238                 rc = 0;
 239
 240         cpi_free_req(req);
 241         sclp_unregister(&sclp_cpi_event);
 242
 243         return rc;
 244 }
 245
 246
 247 static void __exit cpi_module_exit(void)
 248 {
 249 }
 250
 251
 252 /* declare driver module init/cleanup functions */
 253 module_init(cpi_module_init);
 254 module_exit(cpi_module_exit);
 255