1#include <linux/init.h>
2#include <linux/proc_fs.h>
3#include <linux/capability.h>
4#include <linux/ctype.h>
5#include <linux/module.h>
6#include <linux/seq_file.h>
7#include <asm/uaccess.h>
8
9#define LINE_SIZE 80
10
11#include <asm/mtrr.h>
12#include "mtrr.h"
13
14#define FILE_FCOUNT(f) (((struct seq_file *)((f)->private_data))->private)
15
16static const char *const mtrr_strings[MTRR_NUM_TYPES] =
17{
18 "uncachable",
19 "write-combining",
20 "?",
21 "?",
22 "write-through",
23 "write-protect",
24 "write-back",
25};
26
27const char *mtrr_attrib_to_str(int x)
28{
29 return (x <= 6) ? mtrr_strings[x] : "?";
30}
31
32#ifdef CONFIG_PROC_FS
33
34static int
35mtrr_file_add(unsigned long base, unsigned long size,
36 unsigned int type, bool increment, struct file *file, int page)
37{
38 int reg, max;
39 unsigned int *fcount = FILE_FCOUNT(file);
40
41 max = num_var_ranges;
42 if (fcount == NULL) {
43 fcount = kzalloc(max * sizeof *fcount, GFP_KERNEL);
44 if (!fcount)
45 return -ENOMEM;
46 FILE_FCOUNT(file) = fcount;
47 }
48 if (!page) {
49 if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
50 return -EINVAL;
51 base >>= PAGE_SHIFT;
52 size >>= PAGE_SHIFT;
53 }
54 reg = mtrr_add_page(base, size, type, true);
55 if (reg >= 0)
56 ++fcount[reg];
57 return reg;
58}
59
60static int
61mtrr_file_del(unsigned long base, unsigned long size,
62 struct file *file, int page)
63{
64 int reg;
65 unsigned int *fcount = FILE_FCOUNT(file);
66
67 if (!page) {
68 if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
69 return -EINVAL;
70 base >>= PAGE_SHIFT;
71 size >>= PAGE_SHIFT;
72 }
73 reg = mtrr_del_page(-1, base, size);
74 if (reg < 0)
75 return reg;
76 if (fcount == NULL)
77 return reg;
78 if (fcount[reg] < 1)
79 return -EINVAL;
80 --fcount[reg];
81 return reg;
82}
83
84
85static ssize_t
86mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos)
87
88
89
90
91{
92 int i, err;
93 unsigned long reg;
94 unsigned long long base, size;
95 char *ptr;
96 char line[LINE_SIZE];
97 size_t linelen;
98
99 if (!capable(CAP_SYS_ADMIN))
100 return -EPERM;
101 if (!len)
102 return -EINVAL;
103 memset(line, 0, LINE_SIZE);
104 if (len > LINE_SIZE)
105 len = LINE_SIZE;
106 if (copy_from_user(line, buf, len - 1))
107 return -EFAULT;
108 linelen = strlen(line);
109 ptr = line + linelen - 1;
110 if (linelen && *ptr == '\n')
111 *ptr = '\0';
112 if (!strncmp(line, "disable=", 8)) {
113 reg = simple_strtoul(line + 8, &ptr, 0);
114 err = mtrr_del_page(reg, 0, 0);
115 if (err < 0)
116 return err;
117 return len;
118 }
119 if (strncmp(line, "base=", 5))
120 return -EINVAL;
121 base = simple_strtoull(line + 5, &ptr, 0);
122 for (; isspace(*ptr); ++ptr) ;
123 if (strncmp(ptr, "size=", 5))
124 return -EINVAL;
125 size = simple_strtoull(ptr + 5, &ptr, 0);
126 if ((base & 0xfff) || (size & 0xfff))
127 return -EINVAL;
128 for (; isspace(*ptr); ++ptr) ;
129 if (strncmp(ptr, "type=", 5))
130 return -EINVAL;
131 ptr += 5;
132 for (; isspace(*ptr); ++ptr) ;
133 for (i = 0; i < MTRR_NUM_TYPES; ++i) {
134 if (strcmp(ptr, mtrr_strings[i]))
135 continue;
136 base >>= PAGE_SHIFT;
137 size >>= PAGE_SHIFT;
138 err =
139 mtrr_add_page((unsigned long) base, (unsigned long) size, i,
140 true);
141 if (err < 0)
142 return err;
143 return len;
144 }
145 return -EINVAL;
146}
147
148static long
149mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
150{
151 int err = 0;
152 mtrr_type type;
153 unsigned long size;
154 struct mtrr_sentry sentry;
155 struct mtrr_gentry gentry;
156 void __user *arg = (void __user *) __arg;
157
158 switch (cmd) {
159 case MTRRIOC_ADD_ENTRY:
160 case MTRRIOC_SET_ENTRY:
161 case MTRRIOC_DEL_ENTRY:
162 case MTRRIOC_KILL_ENTRY:
163 case MTRRIOC_ADD_PAGE_ENTRY:
164 case MTRRIOC_SET_PAGE_ENTRY:
165 case MTRRIOC_DEL_PAGE_ENTRY:
166 case MTRRIOC_KILL_PAGE_ENTRY:
167 if (copy_from_user(&sentry, arg, sizeof sentry))
168 return -EFAULT;
169 break;
170 case MTRRIOC_GET_ENTRY:
171 case MTRRIOC_GET_PAGE_ENTRY:
172 if (copy_from_user(&gentry, arg, sizeof gentry))
173 return -EFAULT;
174 break;
175#ifdef CONFIG_COMPAT
176 case MTRRIOC32_ADD_ENTRY:
177 case MTRRIOC32_SET_ENTRY:
178 case MTRRIOC32_DEL_ENTRY:
179 case MTRRIOC32_KILL_ENTRY:
180 case MTRRIOC32_ADD_PAGE_ENTRY:
181 case MTRRIOC32_SET_PAGE_ENTRY:
182 case MTRRIOC32_DEL_PAGE_ENTRY:
183 case MTRRIOC32_KILL_PAGE_ENTRY: {
184 struct mtrr_sentry32 __user *s32 = (struct mtrr_sentry32 __user *)__arg;
185 err = get_user(sentry.base, &s32->base);
186 err |= get_user(sentry.size, &s32->size);
187 err |= get_user(sentry.type, &s32->type);
188 if (err)
189 return err;
190 break;
191 }
192 case MTRRIOC32_GET_ENTRY:
193 case MTRRIOC32_GET_PAGE_ENTRY: {
194 struct mtrr_gentry32 __user *g32 = (struct mtrr_gentry32 __user *)__arg;
195 err = get_user(gentry.regnum, &g32->regnum);
196 err |= get_user(gentry.base, &g32->base);
197 err |= get_user(gentry.size, &g32->size);
198 err |= get_user(gentry.type, &g32->type);
199 if (err)
200 return err;
201 break;
202 }
203#endif
204 }
205
206 switch (cmd) {
207 default:
208 return -ENOTTY;
209 case MTRRIOC_ADD_ENTRY:
210#ifdef CONFIG_COMPAT
211 case MTRRIOC32_ADD_ENTRY:
212#endif
213 if (!capable(CAP_SYS_ADMIN))
214 return -EPERM;
215 err =
216 mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
217 file, 0);
218 break;
219 case MTRRIOC_SET_ENTRY:
220#ifdef CONFIG_COMPAT
221 case MTRRIOC32_SET_ENTRY:
222#endif
223 if (!capable(CAP_SYS_ADMIN))
224 return -EPERM;
225 err = mtrr_add(sentry.base, sentry.size, sentry.type, false);
226 break;
227 case MTRRIOC_DEL_ENTRY:
228#ifdef CONFIG_COMPAT
229 case MTRRIOC32_DEL_ENTRY:
230#endif
231 if (!capable(CAP_SYS_ADMIN))
232 return -EPERM;
233 err = mtrr_file_del(sentry.base, sentry.size, file, 0);
234 break;
235 case MTRRIOC_KILL_ENTRY:
236#ifdef CONFIG_COMPAT
237 case MTRRIOC32_KILL_ENTRY:
238#endif
239 if (!capable(CAP_SYS_ADMIN))
240 return -EPERM;
241 err = mtrr_del(-1, sentry.base, sentry.size);
242 break;
243 case MTRRIOC_GET_ENTRY:
244#ifdef CONFIG_COMPAT
245 case MTRRIOC32_GET_ENTRY:
246#endif
247 if (gentry.regnum >= num_var_ranges)
248 return -EINVAL;
249 mtrr_if->get(gentry.regnum, &gentry.base, &size, &type);
250
251
252 if (gentry.base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))
253 || size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)))
254 gentry.base = gentry.size = gentry.type = 0;
255 else {
256 gentry.base <<= PAGE_SHIFT;
257 gentry.size = size << PAGE_SHIFT;
258 gentry.type = type;
259 }
260
261 break;
262 case MTRRIOC_ADD_PAGE_ENTRY:
263#ifdef CONFIG_COMPAT
264 case MTRRIOC32_ADD_PAGE_ENTRY:
265#endif
266 if (!capable(CAP_SYS_ADMIN))
267 return -EPERM;
268 err =
269 mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
270 file, 1);
271 break;
272 case MTRRIOC_SET_PAGE_ENTRY:
273#ifdef CONFIG_COMPAT
274 case MTRRIOC32_SET_PAGE_ENTRY:
275#endif
276 if (!capable(CAP_SYS_ADMIN))
277 return -EPERM;
278 err =
279 mtrr_add_page(sentry.base, sentry.size, sentry.type, false);
280 break;
281 case MTRRIOC_DEL_PAGE_ENTRY:
282#ifdef CONFIG_COMPAT
283 case MTRRIOC32_DEL_PAGE_ENTRY:
284#endif
285 if (!capable(CAP_SYS_ADMIN))
286 return -EPERM;
287 err = mtrr_file_del(sentry.base, sentry.size, file, 1);
288 break;
289 case MTRRIOC_KILL_PAGE_ENTRY:
290#ifdef CONFIG_COMPAT
291 case MTRRIOC32_KILL_PAGE_ENTRY:
292#endif
293 if (!capable(CAP_SYS_ADMIN))
294 return -EPERM;
295 err = mtrr_del_page(-1, sentry.base, sentry.size);
296 break;
297 case MTRRIOC_GET_PAGE_ENTRY:
298#ifdef CONFIG_COMPAT
299 case MTRRIOC32_GET_PAGE_ENTRY:
300#endif
301 if (gentry.regnum >= num_var_ranges)
302 return -EINVAL;
303 mtrr_if->get(gentry.regnum, &gentry.base, &size, &type);
304
305 if (size != (__typeof__(gentry.size))size)
306 gentry.base = gentry.size = gentry.type = 0;
307 else {
308 gentry.size = size;
309 gentry.type = type;
310 }
311 break;
312 }
313
314 if (err)
315 return err;
316
317 switch(cmd) {
318 case MTRRIOC_GET_ENTRY:
319 case MTRRIOC_GET_PAGE_ENTRY:
320 if (copy_to_user(arg, &gentry, sizeof gentry))
321 err = -EFAULT;
322 break;
323#ifdef CONFIG_COMPAT
324 case MTRRIOC32_GET_ENTRY:
325 case MTRRIOC32_GET_PAGE_ENTRY: {
326 struct mtrr_gentry32 __user *g32 = (struct mtrr_gentry32 __user *)__arg;
327 err = put_user(gentry.base, &g32->base);
328 err |= put_user(gentry.size, &g32->size);
329 err |= put_user(gentry.regnum, &g32->regnum);
330 err |= put_user(gentry.type, &g32->type);
331 break;
332 }
333#endif
334 }
335 return err;
336}
337
338static int
339mtrr_close(struct inode *ino, struct file *file)
340{
341 int i, max;
342 unsigned int *fcount = FILE_FCOUNT(file);
343
344 if (fcount != NULL) {
345 max = num_var_ranges;
346 for (i = 0; i < max; ++i) {
347 while (fcount[i] > 0) {
348 mtrr_del(i, 0, 0);
349 --fcount[i];
350 }
351 }
352 kfree(fcount);
353 FILE_FCOUNT(file) = NULL;
354 }
355 return single_release(ino, file);
356}
357
358static int mtrr_seq_show(struct seq_file *seq, void *offset);
359
360static int mtrr_open(struct inode *inode, struct file *file)
361{
362 if (!mtrr_if)
363 return -EIO;
364 if (!mtrr_if->get)
365 return -ENXIO;
366 return single_open(file, mtrr_seq_show, NULL);
367}
368
369static const struct file_operations mtrr_fops = {
370 .owner = THIS_MODULE,
371 .open = mtrr_open,
372 .read = seq_read,
373 .llseek = seq_lseek,
374 .write = mtrr_write,
375 .unlocked_ioctl = mtrr_ioctl,
376 .compat_ioctl = mtrr_ioctl,
377 .release = mtrr_close,
378};
379
380
381static struct proc_dir_entry *proc_root_mtrr;
382
383
384static int mtrr_seq_show(struct seq_file *seq, void *offset)
385{
386 char factor;
387 int i, max, len;
388 mtrr_type type;
389 unsigned long base, size;
390
391 len = 0;
392 max = num_var_ranges;
393 for (i = 0; i < max; i++) {
394 mtrr_if->get(i, &base, &size, &type);
395 if (size == 0)
396 mtrr_usage_table[i] = 0;
397 else {
398 if (size < (0x100000 >> PAGE_SHIFT)) {
399
400 factor = 'K';
401 size <<= PAGE_SHIFT - 10;
402 } else {
403 factor = 'M';
404 size >>= 20 - PAGE_SHIFT;
405 }
406
407 len += seq_printf(seq,
408 "reg%02i: base=0x%05lx000 (%4luMB), size=%4lu%cB: %s, count=%d\n",
409 i, base, base >> (20 - PAGE_SHIFT), size, factor,
410 mtrr_attrib_to_str(type), mtrr_usage_table[i]);
411 }
412 }
413 return 0;
414}
415
416static int __init mtrr_if_init(void)
417{
418 struct cpuinfo_x86 *c = &boot_cpu_data;
419
420 if ((!cpu_has(c, X86_FEATURE_MTRR)) &&
421 (!cpu_has(c, X86_FEATURE_K6_MTRR)) &&
422 (!cpu_has(c, X86_FEATURE_CYRIX_ARR)) &&
423 (!cpu_has(c, X86_FEATURE_CENTAUR_MCR)))
424 return -ENODEV;
425
426 proc_root_mtrr =
427 create_proc_entry("mtrr", S_IWUSR | S_IRUGO, &proc_root);
428 if (proc_root_mtrr) {
429 proc_root_mtrr->owner = THIS_MODULE;
430 proc_root_mtrr->proc_fops = &mtrr_fops;
431 }
432 return 0;
433}
434
435arch_initcall(mtrr_if_init);
436#endif
437
