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32#include <linux/kernel.h>
33#include <linux/module.h>
34#include <linux/init.h>
35#include <linux/proc_fs.h>
36#include <asm/console.h>
37#include <asm/uaccess.h>
38#include <asm/machvec.h>
39
40#define BASE_DIR "srm_environment"
41#define NAMED_DIR "named_variables"
42#define NUMBERED_DIR "numbered_variables"
43#define VERSION "0.0.6"
44#define NAME "srm_env"
45
46MODULE_AUTHOR("Jan-Benedict Glaw <jbglaw@lug-owl.de>");
47MODULE_DESCRIPTION("Accessing Alpha SRM environment through procfs interface");
48MODULE_LICENSE("GPL");
49
50typedef struct _srm_env {
51 char *name;
52 unsigned long id;
53 struct proc_dir_entry *proc_entry;
54} srm_env_t;
55
56static struct proc_dir_entry *base_dir;
57static struct proc_dir_entry *named_dir;
58static struct proc_dir_entry *numbered_dir;
59static char number[256][4];
60
61static srm_env_t srm_named_entries[] = {
62 { "auto_action", ENV_AUTO_ACTION },
63 { "boot_dev", ENV_BOOT_DEV },
64 { "bootdef_dev", ENV_BOOTDEF_DEV },
65 { "booted_dev", ENV_BOOTED_DEV },
66 { "boot_file", ENV_BOOT_FILE },
67 { "booted_file", ENV_BOOTED_FILE },
68 { "boot_osflags", ENV_BOOT_OSFLAGS },
69 { "booted_osflags", ENV_BOOTED_OSFLAGS },
70 { "boot_reset", ENV_BOOT_RESET },
71 { "dump_dev", ENV_DUMP_DEV },
72 { "enable_audit", ENV_ENABLE_AUDIT },
73 { "license", ENV_LICENSE },
74 { "char_set", ENV_CHAR_SET },
75 { "language", ENV_LANGUAGE },
76 { "tty_dev", ENV_TTY_DEV },
77 { NULL, 0 },
78};
79static srm_env_t srm_numbered_entries[256];
80
81
82static int
83srm_env_read(char *page, char **start, off_t off, int count, int *eof,
84 void *data)
85{
86 int nbytes;
87 unsigned long ret;
88 srm_env_t *entry;
89
90 if (off != 0) {
91 *eof = 1;
92 return 0;
93 }
94
95 entry = (srm_env_t *) data;
96 ret = callback_getenv(entry->id, page, count);
97
98 if ((ret >> 61) == 0) {
99 nbytes = (int) ret;
100 *eof = 1;
101 } else
102 nbytes = -EFAULT;
103
104 return nbytes;
105}
106
107static int
108srm_env_write(struct file *file, const char __user *buffer, unsigned long count,
109 void *data)
110{
111 int res;
112 srm_env_t *entry;
113 char *buf = (char *) __get_free_page(GFP_USER);
114 unsigned long ret1, ret2;
115
116 entry = (srm_env_t *) data;
117
118 if (!buf)
119 return -ENOMEM;
120
121 res = -EINVAL;
122 if (count >= PAGE_SIZE)
123 goto out;
124
125 res = -EFAULT;
126 if (copy_from_user(buf, buffer, count))
127 goto out;
128 buf[count] = '\0';
129
130 ret1 = callback_setenv(entry->id, buf, count);
131 if ((ret1 >> 61) == 0) {
132 do
133 ret2 = callback_save_env();
134 while((ret2 >> 61) == 1);
135 res = (int) ret1;
136 }
137
138 out:
139 free_page((unsigned long)buf);
140 return res;
141}
142
143static void
144srm_env_cleanup(void)
145{
146 srm_env_t *entry;
147 unsigned long var_num;
148
149 if (base_dir) {
150
151
152
153 if (named_dir) {
154 entry = srm_named_entries;
155 while (entry->name != NULL && entry->id != 0) {
156 if (entry->proc_entry) {
157 remove_proc_entry(entry->name,
158 named_dir);
159 entry->proc_entry = NULL;
160 }
161 entry++;
162 }
163 remove_proc_entry(NAMED_DIR, base_dir);
164 }
165
166
167
168
169 if (numbered_dir) {
170 for (var_num = 0; var_num <= 255; var_num++) {
171 entry = &srm_numbered_entries[var_num];
172
173 if (entry->proc_entry) {
174 remove_proc_entry(entry->name,
175 numbered_dir);
176 entry->proc_entry = NULL;
177 entry->name = NULL;
178 }
179 }
180 remove_proc_entry(NUMBERED_DIR, base_dir);
181 }
182
183 remove_proc_entry(BASE_DIR, NULL);
184 }
185
186 return;
187}
188
189static int __init
190srm_env_init(void)
191{
192 srm_env_t *entry;
193 unsigned long var_num;
194
195
196
197
198 if (!alpha_using_srm) {
199 printk(KERN_INFO "%s: This Alpha system doesn't "
200 "know about SRM (or you've booted "
201 "SRM->MILO->Linux, which gets "
202 "misdetected)...\n", __FUNCTION__);
203 return -ENODEV;
204 }
205
206
207
208
209 for (var_num = 0; var_num <= 255; var_num++)
210 sprintf(number[var_num], "%ld", var_num);
211
212
213
214
215 base_dir = proc_mkdir(BASE_DIR, NULL);
216 if (!base_dir) {
217 printk(KERN_ERR "Couldn't create base dir /proc/%s\n",
218 BASE_DIR);
219 goto cleanup;
220 }
221 base_dir->owner = THIS_MODULE;
222
223
224
225
226 named_dir = proc_mkdir(NAMED_DIR, base_dir);
227 if (!named_dir) {
228 printk(KERN_ERR "Couldn't create dir /proc/%s/%s\n",
229 BASE_DIR, NAMED_DIR);
230 goto cleanup;
231 }
232 named_dir->owner = THIS_MODULE;
233
234
235
236
237 numbered_dir = proc_mkdir(NUMBERED_DIR, base_dir);
238 if (!numbered_dir) {
239 printk(KERN_ERR "Couldn't create dir /proc/%s/%s\n",
240 BASE_DIR, NUMBERED_DIR);
241 goto cleanup;
242
243 }
244 numbered_dir->owner = THIS_MODULE;
245
246
247
248
249 entry = srm_named_entries;
250 while (entry->name && entry->id) {
251 entry->proc_entry = create_proc_entry(entry->name,
252 0644, named_dir);
253 if (!entry->proc_entry)
254 goto cleanup;
255
256 entry->proc_entry->data = (void *) entry;
257 entry->proc_entry->owner = THIS_MODULE;
258 entry->proc_entry->read_proc = srm_env_read;
259 entry->proc_entry->write_proc = srm_env_write;
260
261 entry++;
262 }
263
264
265
266
267 for (var_num = 0; var_num <= 255; var_num++) {
268 entry = &srm_numbered_entries[var_num];
269 entry->name = number[var_num];
270
271 entry->proc_entry = create_proc_entry(entry->name,
272 0644, numbered_dir);
273 if (!entry->proc_entry)
274 goto cleanup;
275
276 entry->id = var_num;
277 entry->proc_entry->data = (void *) entry;
278 entry->proc_entry->owner = THIS_MODULE;
279 entry->proc_entry->read_proc = srm_env_read;
280 entry->proc_entry->write_proc = srm_env_write;
281 }
282
283 printk(KERN_INFO "%s: version %s loaded successfully\n", NAME,
284 VERSION);
285
286 return 0;
287
288cleanup:
289 srm_env_cleanup();
290
291 return -ENOMEM;
292}
293
294static void __exit
295srm_env_exit(void)
296{
297 srm_env_cleanup();
298 printk(KERN_INFO "%s: unloaded successfully\n", NAME);
299
300 return;
301}
302
303module_init(srm_env_init);
304module_exit(srm_env_exit);
305
