Merge tag 'pci-v6.16-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
[linux-2.6-block.git] / arch / x86 / kernel / cpu / mtrr / if.c
CommitLineData
b2441318 1// SPDX-License-Identifier: GPL-2.0
a9415644 2#include <linux/capability.h>
1da177e4 3#include <linux/seq_file.h>
26dc67ed
JSR
4#include <linux/uaccess.h>
5#include <linux/proc_fs.h>
26dc67ed 6#include <linux/ctype.h>
e7d2860b 7#include <linux/string.h>
5a0e3ad6 8#include <linux/slab.h>
26dc67ed 9#include <linux/init.h>
1da177e4
LT
10
11#define LINE_SIZE 80
12
13#include <asm/mtrr.h>
26dc67ed 14
1da177e4
LT
15#include "mtrr.h"
16
1da177e4
LT
17#define FILE_FCOUNT(f) (((struct seq_file *)((f)->private_data))->private)
18
365bff80 19static const char *const mtrr_strings[MTRR_NUM_TYPES] =
1da177e4 20{
26dc67ed
JSR
21 "uncachable", /* 0 */
22 "write-combining", /* 1 */
23 "?", /* 2 */
24 "?", /* 3 */
25 "write-through", /* 4 */
26 "write-protect", /* 5 */
27 "write-back", /* 6 */
1da177e4
LT
28};
29
365bff80 30const char *mtrr_attrib_to_str(int x)
1da177e4
LT
31{
32 return (x <= 6) ? mtrr_strings[x] : "?";
33}
34
35#ifdef CONFIG_PROC_FS
36
37static int
38mtrr_file_add(unsigned long base, unsigned long size,
2d2ee8de 39 unsigned int type, bool increment, struct file *file, int page)
1da177e4 40{
26dc67ed 41 unsigned int *fcount = FILE_FCOUNT(file);
1da177e4 42 int reg, max;
1da177e4
LT
43
44 max = num_var_ranges;
45 if (fcount == NULL) {
6396bb22 46 fcount = kcalloc(max, sizeof(*fcount), GFP_KERNEL);
1da177e4
LT
47 if (!fcount)
48 return -ENOMEM;
1da177e4
LT
49 FILE_FCOUNT(file) = fcount;
50 }
51 if (!page) {
52 if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
53 return -EINVAL;
54 base >>= PAGE_SHIFT;
55 size >>= PAGE_SHIFT;
56 }
2d2ee8de 57 reg = mtrr_add_page(base, size, type, true);
1da177e4
LT
58 if (reg >= 0)
59 ++fcount[reg];
60 return reg;
61}
62
63static int
64mtrr_file_del(unsigned long base, unsigned long size,
65 struct file *file, int page)
66{
1da177e4 67 unsigned int *fcount = FILE_FCOUNT(file);
26dc67ed 68 int reg;
1da177e4
LT
69
70 if (!page) {
71 if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
72 return -EINVAL;
73 base >>= PAGE_SHIFT;
74 size >>= PAGE_SHIFT;
75 }
76 reg = mtrr_del_page(-1, base, size);
77 if (reg < 0)
78 return reg;
79 if (fcount == NULL)
80 return reg;
81 if (fcount[reg] < 1)
82 return -EINVAL;
83 --fcount[reg];
84 return reg;
85}
86
26dc67ed
JSR
87/*
88 * seq_file can seek but we ignore it.
89 *
90 * Format of control line:
91 * "base=%Lx size=%Lx type=%s" or "disable=%d"
92 */
1da177e4
LT
93static ssize_t
94mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos)
1da177e4
LT
95{
96 int i, err;
97 unsigned long reg;
98 unsigned long long base, size;
99 char *ptr;
100 char line[LINE_SIZE];
11879ba5 101 int length;
1da177e4 102
1da177e4 103 memset(line, 0, LINE_SIZE);
11879ba5 104
15279df6
JH
105 len = min_t(size_t, len, LINE_SIZE - 1);
106 length = strncpy_from_user(line, buf, len);
11879ba5 107 if (length < 0)
7f8ec5a4 108 return length;
26dc67ed 109
8e8f0306
TB
110 ptr = line + length - 1;
111 if (length && *ptr == '\n')
1da177e4 112 *ptr = '\0';
26dc67ed 113
1da177e4
LT
114 if (!strncmp(line, "disable=", 8)) {
115 reg = simple_strtoul(line + 8, &ptr, 0);
116 err = mtrr_del_page(reg, 0, 0);
117 if (err < 0)
118 return err;
119 return len;
120 }
26dc67ed 121
1da177e4
LT
122 if (strncmp(line, "base=", 5))
123 return -EINVAL;
26dc67ed 124
1da177e4 125 base = simple_strtoull(line + 5, &ptr, 0);
e7d2860b 126 ptr = skip_spaces(ptr);
26dc67ed 127
1da177e4
LT
128 if (strncmp(ptr, "size=", 5))
129 return -EINVAL;
26dc67ed 130
1da177e4
LT
131 size = simple_strtoull(ptr + 5, &ptr, 0);
132 if ((base & 0xfff) || (size & 0xfff))
133 return -EINVAL;
e7d2860b 134 ptr = skip_spaces(ptr);
26dc67ed 135
1da177e4
LT
136 if (strncmp(ptr, "type=", 5))
137 return -EINVAL;
e7d2860b 138 ptr = skip_spaces(ptr + 5);
26dc67ed 139
13a4db9d
AS
140 i = match_string(mtrr_strings, MTRR_NUM_TYPES, ptr);
141 if (i < 0)
142 return i;
143
144 base >>= PAGE_SHIFT;
145 size >>= PAGE_SHIFT;
146 err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true);
147 if (err < 0)
148 return err;
149 return len;
1da177e4
LT
150}
151
c5311781
BG
152static long
153mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
1da177e4 154{
c5311781 155 int err = 0;
1da177e4 156 mtrr_type type;
b263b31e 157 unsigned long base;
365bff80 158 unsigned long size;
1da177e4
LT
159 struct mtrr_sentry sentry;
160 struct mtrr_gentry gentry;
161 void __user *arg = (void __user *) __arg;
162
32043fa0
CIK
163 memset(&gentry, 0, sizeof(gentry));
164
c5311781
BG
165 switch (cmd) {
166 case MTRRIOC_ADD_ENTRY:
167 case MTRRIOC_SET_ENTRY:
168 case MTRRIOC_DEL_ENTRY:
169 case MTRRIOC_KILL_ENTRY:
170 case MTRRIOC_ADD_PAGE_ENTRY:
171 case MTRRIOC_SET_PAGE_ENTRY:
172 case MTRRIOC_DEL_PAGE_ENTRY:
173 case MTRRIOC_KILL_PAGE_ENTRY:
0e96f31e 174 if (copy_from_user(&sentry, arg, sizeof(sentry)))
c5311781
BG
175 return -EFAULT;
176 break;
177 case MTRRIOC_GET_ENTRY:
178 case MTRRIOC_GET_PAGE_ENTRY:
0e96f31e 179 if (copy_from_user(&gentry, arg, sizeof(gentry)))
c5311781
BG
180 return -EFAULT;
181 break;
182#ifdef CONFIG_COMPAT
183 case MTRRIOC32_ADD_ENTRY:
184 case MTRRIOC32_SET_ENTRY:
185 case MTRRIOC32_DEL_ENTRY:
186 case MTRRIOC32_KILL_ENTRY:
187 case MTRRIOC32_ADD_PAGE_ENTRY:
188 case MTRRIOC32_SET_PAGE_ENTRY:
189 case MTRRIOC32_DEL_PAGE_ENTRY:
190 case MTRRIOC32_KILL_PAGE_ENTRY: {
26dc67ed
JSR
191 struct mtrr_sentry32 __user *s32;
192
193 s32 = (struct mtrr_sentry32 __user *)__arg;
c5311781
BG
194 err = get_user(sentry.base, &s32->base);
195 err |= get_user(sentry.size, &s32->size);
196 err |= get_user(sentry.type, &s32->type);
197 if (err)
198 return err;
199 break;
200 }
201 case MTRRIOC32_GET_ENTRY:
202 case MTRRIOC32_GET_PAGE_ENTRY: {
26dc67ed
JSR
203 struct mtrr_gentry32 __user *g32;
204
205 g32 = (struct mtrr_gentry32 __user *)__arg;
c5311781
BG
206 err = get_user(gentry.regnum, &g32->regnum);
207 err |= get_user(gentry.base, &g32->base);
208 err |= get_user(gentry.size, &g32->size);
209 err |= get_user(gentry.type, &g32->type);
210 if (err)
211 return err;
212 break;
213 }
214#endif
215 }
216
1da177e4
LT
217 switch (cmd) {
218 default:
219 return -ENOTTY;
220 case MTRRIOC_ADD_ENTRY:
98838ec9
GP
221#ifdef CONFIG_COMPAT
222 case MTRRIOC32_ADD_ENTRY:
223#endif
1da177e4 224 err =
2d2ee8de 225 mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
1da177e4 226 file, 0);
1da177e4
LT
227 break;
228 case MTRRIOC_SET_ENTRY:
98838ec9
GP
229#ifdef CONFIG_COMPAT
230 case MTRRIOC32_SET_ENTRY:
231#endif
2d2ee8de 232 err = mtrr_add(sentry.base, sentry.size, sentry.type, false);
1da177e4
LT
233 break;
234 case MTRRIOC_DEL_ENTRY:
98838ec9
GP
235#ifdef CONFIG_COMPAT
236 case MTRRIOC32_DEL_ENTRY:
237#endif
1da177e4 238 err = mtrr_file_del(sentry.base, sentry.size, file, 0);
1da177e4
LT
239 break;
240 case MTRRIOC_KILL_ENTRY:
98838ec9
GP
241#ifdef CONFIG_COMPAT
242 case MTRRIOC32_KILL_ENTRY:
243#endif
1da177e4 244 err = mtrr_del(-1, sentry.base, sentry.size);
1da177e4
LT
245 break;
246 case MTRRIOC_GET_ENTRY:
98838ec9
GP
247#ifdef CONFIG_COMPAT
248 case MTRRIOC32_GET_ENTRY:
249#endif
1da177e4
LT
250 if (gentry.regnum >= num_var_ranges)
251 return -EINVAL;
b263b31e 252 mtrr_if->get(gentry.regnum, &base, &size, &type);
1da177e4
LT
253
254 /* Hide entries that go above 4GB */
b263b31e 255 if (base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))
365bff80 256 || size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)))
1da177e4
LT
257 gentry.base = gentry.size = gentry.type = 0;
258 else {
b263b31e 259 gentry.base = base << PAGE_SHIFT;
365bff80 260 gentry.size = size << PAGE_SHIFT;
1da177e4
LT
261 gentry.type = type;
262 }
263
1da177e4
LT
264 break;
265 case MTRRIOC_ADD_PAGE_ENTRY:
98838ec9
GP
266#ifdef CONFIG_COMPAT
267 case MTRRIOC32_ADD_PAGE_ENTRY:
268#endif
1da177e4 269 err =
2d2ee8de 270 mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
1da177e4 271 file, 1);
1da177e4
LT
272 break;
273 case MTRRIOC_SET_PAGE_ENTRY:
98838ec9
GP
274#ifdef CONFIG_COMPAT
275 case MTRRIOC32_SET_PAGE_ENTRY:
276#endif
2d2ee8de
PJ
277 err =
278 mtrr_add_page(sentry.base, sentry.size, sentry.type, false);
1da177e4
LT
279 break;
280 case MTRRIOC_DEL_PAGE_ENTRY:
98838ec9
GP
281#ifdef CONFIG_COMPAT
282 case MTRRIOC32_DEL_PAGE_ENTRY:
283#endif
1da177e4 284 err = mtrr_file_del(sentry.base, sentry.size, file, 1);
1da177e4
LT
285 break;
286 case MTRRIOC_KILL_PAGE_ENTRY:
98838ec9
GP
287#ifdef CONFIG_COMPAT
288 case MTRRIOC32_KILL_PAGE_ENTRY:
289#endif
1da177e4 290 err = mtrr_del_page(-1, sentry.base, sentry.size);
1da177e4
LT
291 break;
292 case MTRRIOC_GET_PAGE_ENTRY:
98838ec9
GP
293#ifdef CONFIG_COMPAT
294 case MTRRIOC32_GET_PAGE_ENTRY:
295#endif
1da177e4
LT
296 if (gentry.regnum >= num_var_ranges)
297 return -EINVAL;
b263b31e 298 mtrr_if->get(gentry.regnum, &base, &size, &type);
365bff80
JB
299 /* Hide entries that would overflow */
300 if (size != (__typeof__(gentry.size))size)
301 gentry.base = gentry.size = gentry.type = 0;
302 else {
b263b31e 303 gentry.base = base;
365bff80
JB
304 gentry.size = size;
305 gentry.type = type;
306 }
c5311781
BG
307 break;
308 }
1da177e4 309
c5311781
BG
310 if (err)
311 return err;
312
26dc67ed 313 switch (cmd) {
c5311781
BG
314 case MTRRIOC_GET_ENTRY:
315 case MTRRIOC_GET_PAGE_ENTRY:
0e96f31e 316 if (copy_to_user(arg, &gentry, sizeof(gentry)))
c5311781 317 err = -EFAULT;
1da177e4 318 break;
c5311781
BG
319#ifdef CONFIG_COMPAT
320 case MTRRIOC32_GET_ENTRY:
321 case MTRRIOC32_GET_PAGE_ENTRY: {
26dc67ed
JSR
322 struct mtrr_gentry32 __user *g32;
323
324 g32 = (struct mtrr_gentry32 __user *)__arg;
c5311781
BG
325 err = put_user(gentry.base, &g32->base);
326 err |= put_user(gentry.size, &g32->size);
327 err |= put_user(gentry.regnum, &g32->regnum);
328 err |= put_user(gentry.type, &g32->type);
329 break;
330 }
331#endif
1da177e4 332 }
c5311781 333 return err;
1da177e4
LT
334}
335
26dc67ed 336static int mtrr_close(struct inode *ino, struct file *file)
1da177e4 337{
1da177e4 338 unsigned int *fcount = FILE_FCOUNT(file);
26dc67ed 339 int i, max;
1da177e4
LT
340
341 if (fcount != NULL) {
342 max = num_var_ranges;
343 for (i = 0; i < max; ++i) {
344 while (fcount[i] > 0) {
345 mtrr_del(i, 0, 0);
346 --fcount[i];
347 }
348 }
349 kfree(fcount);
350 FILE_FCOUNT(file) = NULL;
351 }
352 return single_release(ino, file);
353}
354
1da177e4
LT
355static int mtrr_seq_show(struct seq_file *seq, void *offset)
356{
357 char factor;
3ac62bc0 358 int i, max;
1da177e4 359 mtrr_type type;
365bff80 360 unsigned long base, size;
1da177e4 361
1da177e4
LT
362 max = num_var_ranges;
363 for (i = 0; i < max; i++) {
364 mtrr_if->get(i, &base, &size, &type);
26dc67ed 365 if (size == 0) {
99fc8d42 366 mtrr_usage_table[i] = 0;
26dc67ed 367 continue;
1da177e4 368 }
26dc67ed
JSR
369 if (size < (0x100000 >> PAGE_SHIFT)) {
370 /* less than 1MB */
371 factor = 'K';
372 size <<= PAGE_SHIFT - 10;
373 } else {
374 factor = 'M';
375 size >>= 20 - PAGE_SHIFT;
376 }
377 /* Base can be > 32bit */
3ac62bc0
JP
378 seq_printf(seq, "reg%02i: base=0x%06lx000 (%5luMB), size=%5lu%cB, count=%d: %s\n",
379 i, base, base >> (20 - PAGE_SHIFT),
380 size, factor,
381 mtrr_usage_table[i], mtrr_attrib_to_str(type));
1da177e4
LT
382 }
383 return 0;
384}
385
2e30dd9e
BP
386static int mtrr_open(struct inode *inode, struct file *file)
387{
388 if (!mtrr_if)
389 return -EIO;
390 if (!mtrr_if->get)
391 return -ENXIO;
4fc265a9
KC
392 if (!capable(CAP_SYS_ADMIN))
393 return -EPERM;
2e30dd9e
BP
394 return single_open(file, mtrr_seq_show, NULL);
395}
396
97a32539
AD
397static const struct proc_ops mtrr_proc_ops = {
398 .proc_open = mtrr_open,
399 .proc_read = seq_read,
400 .proc_lseek = seq_lseek,
401 .proc_write = mtrr_write,
402 .proc_ioctl = mtrr_ioctl,
403#ifdef CONFIG_COMPAT
404 .proc_compat_ioctl = mtrr_ioctl,
405#endif
406 .proc_release = mtrr_close,
2e30dd9e
BP
407};
408
1da177e4
LT
409static int __init mtrr_if_init(void)
410{
411 struct cpuinfo_x86 *c = &boot_cpu_data;
412
413 if ((!cpu_has(c, X86_FEATURE_MTRR)) &&
414 (!cpu_has(c, X86_FEATURE_K6_MTRR)) &&
415 (!cpu_has(c, X86_FEATURE_CYRIX_ARR)) &&
416 (!cpu_has(c, X86_FEATURE_CENTAUR_MCR)))
417 return -ENODEV;
418
97a32539 419 proc_create("mtrr", S_IWUSR | S_IRUGO, NULL, &mtrr_proc_ops);
1da177e4
LT
420 return 0;
421}
1da177e4
LT
422arch_initcall(mtrr_if_init);
423#endif /* CONFIG_PROC_FS */