Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * srm_env.c - Access to SRM environment | |
3 | * variables through linux' procfs | |
4 | * | |
16b7f4dc | 5 | * (C) 2001,2002,2006 by Jan-Benedict Glaw <jbglaw@lug-owl.de> |
1da177e4 LT |
6 | * |
7 | * This driver is at all a modified version of Erik Mouw's | |
8 | * Documentation/DocBook/procfs_example.c, so: thank | |
9 | * you, Erik! He can be reached via email at | |
10 | * <J.A.K.Mouw@its.tudelft.nl>. It is based on an idea | |
11 | * provided by DEC^WCompaq^WIntel's "Jumpstart" CD. They | |
12 | * included a patch like this as well. Thanks for idea! | |
13 | * | |
14 | * This program is free software; you can redistribute | |
15 | * it and/or modify it under the terms of the GNU General | |
16 | * Public License version 2 as published by the Free Software | |
17 | * Foundation. | |
18 | * | |
19 | * This program is distributed in the hope that it will be | |
20 | * useful, but WITHOUT ANY WARRANTY; without even the implied | |
21 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR | |
22 | * PURPOSE. See the GNU General Public License for more | |
23 | * details. | |
16b7f4dc | 24 | * |
1da177e4 LT |
25 | * You should have received a copy of the GNU General Public |
26 | * License along with this program; if not, write to the | |
27 | * Free Software Foundation, Inc., 59 Temple Place, | |
28 | * Suite 330, Boston, MA 02111-1307 USA | |
29 | * | |
30 | */ | |
31 | ||
1da177e4 | 32 | #include <linux/kernel.h> |
5a0e3ad6 | 33 | #include <linux/gfp.h> |
1da177e4 LT |
34 | #include <linux/module.h> |
35 | #include <linux/init.h> | |
36 | #include <linux/proc_fs.h> | |
0ead0f84 | 37 | #include <linux/seq_file.h> |
1da177e4 LT |
38 | #include <asm/console.h> |
39 | #include <asm/uaccess.h> | |
40 | #include <asm/machvec.h> | |
41 | ||
42 | #define BASE_DIR "srm_environment" /* Subdir in /proc/ */ | |
43 | #define NAMED_DIR "named_variables" /* Subdir for known variables */ | |
44 | #define NUMBERED_DIR "numbered_variables" /* Subdir for all variables */ | |
16b7f4dc | 45 | #define VERSION "0.0.6" /* Module version */ |
1da177e4 LT |
46 | #define NAME "srm_env" /* Module name */ |
47 | ||
48 | MODULE_AUTHOR("Jan-Benedict Glaw <jbglaw@lug-owl.de>"); | |
49 | MODULE_DESCRIPTION("Accessing Alpha SRM environment through procfs interface"); | |
50 | MODULE_LICENSE("GPL"); | |
51 | ||
52 | typedef struct _srm_env { | |
53 | char *name; | |
54 | unsigned long id; | |
55 | struct proc_dir_entry *proc_entry; | |
56 | } srm_env_t; | |
57 | ||
58 | static struct proc_dir_entry *base_dir; | |
59 | static struct proc_dir_entry *named_dir; | |
60 | static struct proc_dir_entry *numbered_dir; | |
61 | static char number[256][4]; | |
62 | ||
63 | static srm_env_t srm_named_entries[] = { | |
64 | { "auto_action", ENV_AUTO_ACTION }, | |
65 | { "boot_dev", ENV_BOOT_DEV }, | |
66 | { "bootdef_dev", ENV_BOOTDEF_DEV }, | |
67 | { "booted_dev", ENV_BOOTED_DEV }, | |
68 | { "boot_file", ENV_BOOT_FILE }, | |
69 | { "booted_file", ENV_BOOTED_FILE }, | |
70 | { "boot_osflags", ENV_BOOT_OSFLAGS }, | |
71 | { "booted_osflags", ENV_BOOTED_OSFLAGS }, | |
72 | { "boot_reset", ENV_BOOT_RESET }, | |
73 | { "dump_dev", ENV_DUMP_DEV }, | |
74 | { "enable_audit", ENV_ENABLE_AUDIT }, | |
75 | { "license", ENV_LICENSE }, | |
76 | { "char_set", ENV_CHAR_SET }, | |
77 | { "language", ENV_LANGUAGE }, | |
78 | { "tty_dev", ENV_TTY_DEV }, | |
79 | { NULL, 0 }, | |
80 | }; | |
81 | static srm_env_t srm_numbered_entries[256]; | |
82 | ||
83 | ||
0ead0f84 | 84 | static int srm_env_proc_show(struct seq_file *m, void *v) |
1da177e4 | 85 | { |
1da177e4 LT |
86 | unsigned long ret; |
87 | srm_env_t *entry; | |
0ead0f84 | 88 | char *page; |
1da177e4 | 89 | |
0ead0f84 AD |
90 | entry = (srm_env_t *)m->private; |
91 | page = (char *)__get_free_page(GFP_USER); | |
92 | if (!page) | |
93 | return -ENOMEM; | |
1da177e4 | 94 | |
0ead0f84 | 95 | ret = callback_getenv(entry->id, page, PAGE_SIZE); |
1da177e4 | 96 | |
16b7f4dc | 97 | if ((ret >> 61) == 0) { |
0ead0f84 AD |
98 | seq_write(m, page, ret); |
99 | ret = 0; | |
16b7f4dc | 100 | } else |
0ead0f84 AD |
101 | ret = -EFAULT; |
102 | free_page((unsigned long)page); | |
103 | return ret; | |
104 | } | |
1da177e4 | 105 | |
0ead0f84 AD |
106 | static int srm_env_proc_open(struct inode *inode, struct file *file) |
107 | { | |
108 | return single_open(file, srm_env_proc_show, PDE(inode)->data); | |
1da177e4 LT |
109 | } |
110 | ||
0ead0f84 AD |
111 | static ssize_t srm_env_proc_write(struct file *file, const char __user *buffer, |
112 | size_t count, loff_t *pos) | |
1da177e4 LT |
113 | { |
114 | int res; | |
0ead0f84 | 115 | srm_env_t *entry = PDE(file->f_path.dentry->d_inode)->data; |
1da177e4 LT |
116 | char *buf = (char *) __get_free_page(GFP_USER); |
117 | unsigned long ret1, ret2; | |
118 | ||
1da177e4 LT |
119 | if (!buf) |
120 | return -ENOMEM; | |
121 | ||
122 | res = -EINVAL; | |
123 | if (count >= PAGE_SIZE) | |
124 | goto out; | |
125 | ||
126 | res = -EFAULT; | |
127 | if (copy_from_user(buf, buffer, count)) | |
128 | goto out; | |
129 | buf[count] = '\0'; | |
130 | ||
131 | ret1 = callback_setenv(entry->id, buf, count); | |
132 | if ((ret1 >> 61) == 0) { | |
16b7f4dc | 133 | do |
1da177e4 LT |
134 | ret2 = callback_save_env(); |
135 | while((ret2 >> 61) == 1); | |
136 | res = (int) ret1; | |
137 | } | |
138 | ||
139 | out: | |
140 | free_page((unsigned long)buf); | |
141 | return res; | |
142 | } | |
143 | ||
0ead0f84 AD |
144 | static const struct file_operations srm_env_proc_fops = { |
145 | .owner = THIS_MODULE, | |
146 | .open = srm_env_proc_open, | |
147 | .read = seq_read, | |
148 | .llseek = seq_lseek, | |
149 | .release = single_release, | |
150 | .write = srm_env_proc_write, | |
151 | }; | |
152 | ||
1da177e4 LT |
153 | static void |
154 | srm_env_cleanup(void) | |
155 | { | |
156 | srm_env_t *entry; | |
157 | unsigned long var_num; | |
158 | ||
16b7f4dc | 159 | if (base_dir) { |
1da177e4 LT |
160 | /* |
161 | * Remove named entries | |
162 | */ | |
16b7f4dc | 163 | if (named_dir) { |
1da177e4 | 164 | entry = srm_named_entries; |
16b7f4dc JBG |
165 | while (entry->name != NULL && entry->id != 0) { |
166 | if (entry->proc_entry) { | |
1da177e4 LT |
167 | remove_proc_entry(entry->name, |
168 | named_dir); | |
169 | entry->proc_entry = NULL; | |
170 | } | |
171 | entry++; | |
172 | } | |
173 | remove_proc_entry(NAMED_DIR, base_dir); | |
174 | } | |
175 | ||
176 | /* | |
177 | * Remove numbered entries | |
178 | */ | |
16b7f4dc JBG |
179 | if (numbered_dir) { |
180 | for (var_num = 0; var_num <= 255; var_num++) { | |
1da177e4 LT |
181 | entry = &srm_numbered_entries[var_num]; |
182 | ||
16b7f4dc | 183 | if (entry->proc_entry) { |
1da177e4 LT |
184 | remove_proc_entry(entry->name, |
185 | numbered_dir); | |
186 | entry->proc_entry = NULL; | |
187 | entry->name = NULL; | |
188 | } | |
189 | } | |
190 | remove_proc_entry(NUMBERED_DIR, base_dir); | |
191 | } | |
192 | ||
193 | remove_proc_entry(BASE_DIR, NULL); | |
194 | } | |
195 | ||
196 | return; | |
197 | } | |
198 | ||
1da177e4 LT |
199 | static int __init |
200 | srm_env_init(void) | |
201 | { | |
202 | srm_env_t *entry; | |
203 | unsigned long var_num; | |
204 | ||
205 | /* | |
206 | * Check system | |
207 | */ | |
16b7f4dc | 208 | if (!alpha_using_srm) { |
1da177e4 LT |
209 | printk(KERN_INFO "%s: This Alpha system doesn't " |
210 | "know about SRM (or you've booted " | |
211 | "SRM->MILO->Linux, which gets " | |
bbb8d343 | 212 | "misdetected)...\n", __func__); |
1da177e4 LT |
213 | return -ENODEV; |
214 | } | |
215 | ||
216 | /* | |
217 | * Init numbers | |
218 | */ | |
16b7f4dc | 219 | for (var_num = 0; var_num <= 255; var_num++) |
1da177e4 LT |
220 | sprintf(number[var_num], "%ld", var_num); |
221 | ||
222 | /* | |
223 | * Create base directory | |
224 | */ | |
225 | base_dir = proc_mkdir(BASE_DIR, NULL); | |
16b7f4dc | 226 | if (!base_dir) { |
1da177e4 LT |
227 | printk(KERN_ERR "Couldn't create base dir /proc/%s\n", |
228 | BASE_DIR); | |
229 | goto cleanup; | |
230 | } | |
1da177e4 LT |
231 | |
232 | /* | |
233 | * Create per-name subdirectory | |
234 | */ | |
235 | named_dir = proc_mkdir(NAMED_DIR, base_dir); | |
16b7f4dc | 236 | if (!named_dir) { |
1da177e4 LT |
237 | printk(KERN_ERR "Couldn't create dir /proc/%s/%s\n", |
238 | BASE_DIR, NAMED_DIR); | |
239 | goto cleanup; | |
240 | } | |
1da177e4 LT |
241 | |
242 | /* | |
243 | * Create per-number subdirectory | |
244 | */ | |
245 | numbered_dir = proc_mkdir(NUMBERED_DIR, base_dir); | |
16b7f4dc | 246 | if (!numbered_dir) { |
1da177e4 LT |
247 | printk(KERN_ERR "Couldn't create dir /proc/%s/%s\n", |
248 | BASE_DIR, NUMBERED_DIR); | |
249 | goto cleanup; | |
250 | ||
251 | } | |
1da177e4 LT |
252 | |
253 | /* | |
254 | * Create all named nodes | |
255 | */ | |
256 | entry = srm_named_entries; | |
16b7f4dc | 257 | while (entry->name && entry->id) { |
0ead0f84 AD |
258 | entry->proc_entry = proc_create_data(entry->name, 0644, named_dir, |
259 | &srm_env_proc_fops, entry); | |
16b7f4dc | 260 | if (!entry->proc_entry) |
1da177e4 | 261 | goto cleanup; |
1da177e4 LT |
262 | entry++; |
263 | } | |
264 | ||
265 | /* | |
266 | * Create all numbered nodes | |
267 | */ | |
16b7f4dc | 268 | for (var_num = 0; var_num <= 255; var_num++) { |
1da177e4 LT |
269 | entry = &srm_numbered_entries[var_num]; |
270 | entry->name = number[var_num]; | |
271 | ||
0ead0f84 AD |
272 | entry->proc_entry = proc_create_data(entry->name, 0644, numbered_dir, |
273 | &srm_env_proc_fops, entry); | |
16b7f4dc | 274 | if (!entry->proc_entry) |
1da177e4 LT |
275 | goto cleanup; |
276 | ||
277 | entry->id = var_num; | |
1da177e4 LT |
278 | } |
279 | ||
280 | printk(KERN_INFO "%s: version %s loaded successfully\n", NAME, | |
281 | VERSION); | |
282 | ||
283 | return 0; | |
284 | ||
285 | cleanup: | |
286 | srm_env_cleanup(); | |
287 | ||
288 | return -ENOMEM; | |
289 | } | |
290 | ||
1da177e4 LT |
291 | static void __exit |
292 | srm_env_exit(void) | |
293 | { | |
294 | srm_env_cleanup(); | |
295 | printk(KERN_INFO "%s: unloaded successfully\n", NAME); | |
296 | ||
297 | return; | |
298 | } | |
299 | ||
1da177e4 LT |
300 | module_init(srm_env_init); |
301 | module_exit(srm_env_exit); |