Merge master.kernel.org:/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog
[linux-2.6] / 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 sytem 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