Merge branch 'for-linus' of git://neil.brown.name/md
[linux-2.6] / arch / x86 / mm / pf_in.c
1 /*
2  *  Fault Injection Test harness (FI)
3  *  Copyright (C) Intel Crop.
4  *
5  *  This program is free software; you can redistribute it and/or
6  *  modify it under the terms of the GNU General Public License
7  *  as published by the Free Software Foundation; either version 2
8  *  of the License, or (at your option) any later version.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; if not, write to the Free Software
17  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
18  *  USA.
19  *
20  */
21
22 /*  Id: pf_in.c,v 1.1.1.1 2002/11/12 05:56:32 brlock Exp
23  *  Copyright by Intel Crop., 2002
24  *  Louis Zhuang (louis.zhuang@intel.com)
25  *
26  *  Bjorn Steinbrink (B.Steinbrink@gmx.de), 2007
27  */
28
29 #include <linux/module.h>
30 #include <linux/ptrace.h> /* struct pt_regs */
31 #include "pf_in.h"
32
33 #ifdef __i386__
34 /* IA32 Manual 3, 2-1 */
35 static unsigned char prefix_codes[] = {
36         0xF0, 0xF2, 0xF3, 0x2E, 0x36, 0x3E, 0x26, 0x64,
37         0x65, 0x2E, 0x3E, 0x66, 0x67
38 };
39 /* IA32 Manual 3, 3-432*/
40 static unsigned int reg_rop[] = {
41         0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
42 };
43 static unsigned int reg_wop[] = { 0x88, 0x89 };
44 static unsigned int imm_wop[] = { 0xC6, 0xC7 };
45 /* IA32 Manual 3, 3-432*/
46 static unsigned int rw8[] = { 0x88, 0x8A, 0xC6 };
47 static unsigned int rw32[] = {
48         0x89, 0x8B, 0xC7, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
49 };
50 static unsigned int mw8[] = { 0x88, 0x8A, 0xC6, 0xB60F, 0xBE0F };
51 static unsigned int mw16[] = { 0xB70F, 0xBF0F };
52 static unsigned int mw32[] = { 0x89, 0x8B, 0xC7 };
53 static unsigned int mw64[] = {};
54 #else /* not __i386__ */
55 static unsigned char prefix_codes[] = {
56         0x66, 0x67, 0x2E, 0x3E, 0x26, 0x64, 0x65, 0x36,
57         0xF0, 0xF3, 0xF2,
58         /* REX Prefixes */
59         0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
60         0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
61 };
62 /* AMD64 Manual 3, Appendix A*/
63 static unsigned int reg_rop[] = {
64         0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
65 };
66 static unsigned int reg_wop[] = { 0x88, 0x89 };
67 static unsigned int imm_wop[] = { 0xC6, 0xC7 };
68 static unsigned int rw8[] = { 0xC6, 0x88, 0x8A };
69 static unsigned int rw32[] = {
70         0xC7, 0x89, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
71 };
72 /* 8 bit only */
73 static unsigned int mw8[] = { 0xC6, 0x88, 0x8A, 0xB60F, 0xBE0F };
74 /* 16 bit only */
75 static unsigned int mw16[] = { 0xB70F, 0xBF0F };
76 /* 16 or 32 bit */
77 static unsigned int mw32[] = { 0xC7 };
78 /* 16, 32 or 64 bit */
79 static unsigned int mw64[] = { 0x89, 0x8B };
80 #endif /* not __i386__ */
81
82 static int skip_prefix(unsigned char *addr, int *shorted, int *enlarged,
83                                                                 int *rexr)
84 {
85         int i;
86         unsigned char *p = addr;
87         *shorted = 0;
88         *enlarged = 0;
89         *rexr = 0;
90
91 restart:
92         for (i = 0; i < ARRAY_SIZE(prefix_codes); i++) {
93                 if (*p == prefix_codes[i]) {
94                         if (*p == 0x66)
95                                 *shorted = 1;
96 #ifdef __amd64__
97                         if ((*p & 0xf8) == 0x48)
98                                 *enlarged = 1;
99                         if ((*p & 0xf4) == 0x44)
100                                 *rexr = 1;
101 #endif
102                         p++;
103                         goto restart;
104                 }
105         }
106
107         return (p - addr);
108 }
109
110 static int get_opcode(unsigned char *addr, unsigned int *opcode)
111 {
112         int len;
113
114         if (*addr == 0x0F) {
115                 /* 0x0F is extension instruction */
116                 *opcode = *(unsigned short *)addr;
117                 len = 2;
118         } else {
119                 *opcode = *addr;
120                 len = 1;
121         }
122
123         return len;
124 }
125
126 #define CHECK_OP_TYPE(opcode, array, type) \
127         for (i = 0; i < ARRAY_SIZE(array); i++) { \
128                 if (array[i] == opcode) { \
129                         rv = type; \
130                         goto exit; \
131                 } \
132         }
133
134 enum reason_type get_ins_type(unsigned long ins_addr)
135 {
136         unsigned int opcode;
137         unsigned char *p;
138         int shorted, enlarged, rexr;
139         int i;
140         enum reason_type rv = OTHERS;
141
142         p = (unsigned char *)ins_addr;
143         p += skip_prefix(p, &shorted, &enlarged, &rexr);
144         p += get_opcode(p, &opcode);
145
146         CHECK_OP_TYPE(opcode, reg_rop, REG_READ);
147         CHECK_OP_TYPE(opcode, reg_wop, REG_WRITE);
148         CHECK_OP_TYPE(opcode, imm_wop, IMM_WRITE);
149
150 exit:
151         return rv;
152 }
153 #undef CHECK_OP_TYPE
154
155 static unsigned int get_ins_reg_width(unsigned long ins_addr)
156 {
157         unsigned int opcode;
158         unsigned char *p;
159         int i, shorted, enlarged, rexr;
160
161         p = (unsigned char *)ins_addr;
162         p += skip_prefix(p, &shorted, &enlarged, &rexr);
163         p += get_opcode(p, &opcode);
164
165         for (i = 0; i < ARRAY_SIZE(rw8); i++)
166                 if (rw8[i] == opcode)
167                         return 1;
168
169         for (i = 0; i < ARRAY_SIZE(rw32); i++)
170                 if (rw32[i] == opcode)
171                         return (shorted ? 2 : (enlarged ? 8 : 4));
172
173         printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
174         return 0;
175 }
176
177 unsigned int get_ins_mem_width(unsigned long ins_addr)
178 {
179         unsigned int opcode;
180         unsigned char *p;
181         int i, shorted, enlarged, rexr;
182
183         p = (unsigned char *)ins_addr;
184         p += skip_prefix(p, &shorted, &enlarged, &rexr);
185         p += get_opcode(p, &opcode);
186
187         for (i = 0; i < ARRAY_SIZE(mw8); i++)
188                 if (mw8[i] == opcode)
189                         return 1;
190
191         for (i = 0; i < ARRAY_SIZE(mw16); i++)
192                 if (mw16[i] == opcode)
193                         return 2;
194
195         for (i = 0; i < ARRAY_SIZE(mw32); i++)
196                 if (mw32[i] == opcode)
197                         return shorted ? 2 : 4;
198
199         for (i = 0; i < ARRAY_SIZE(mw64); i++)
200                 if (mw64[i] == opcode)
201                         return shorted ? 2 : (enlarged ? 8 : 4);
202
203         printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
204         return 0;
205 }
206
207 /*
208  * Define register ident in mod/rm byte.
209  * Note: these are NOT the same as in ptrace-abi.h.
210  */
211 enum {
212         arg_AL = 0,
213         arg_CL = 1,
214         arg_DL = 2,
215         arg_BL = 3,
216         arg_AH = 4,
217         arg_CH = 5,
218         arg_DH = 6,
219         arg_BH = 7,
220
221         arg_AX = 0,
222         arg_CX = 1,
223         arg_DX = 2,
224         arg_BX = 3,
225         arg_SP = 4,
226         arg_BP = 5,
227         arg_SI = 6,
228         arg_DI = 7,
229 #ifdef __amd64__
230         arg_R8  = 8,
231         arg_R9  = 9,
232         arg_R10 = 10,
233         arg_R11 = 11,
234         arg_R12 = 12,
235         arg_R13 = 13,
236         arg_R14 = 14,
237         arg_R15 = 15
238 #endif
239 };
240
241 static unsigned char *get_reg_w8(int no, struct pt_regs *regs)
242 {
243         unsigned char *rv = NULL;
244
245         switch (no) {
246         case arg_AL:
247                 rv = (unsigned char *)&regs->ax;
248                 break;
249         case arg_BL:
250                 rv = (unsigned char *)&regs->bx;
251                 break;
252         case arg_CL:
253                 rv = (unsigned char *)&regs->cx;
254                 break;
255         case arg_DL:
256                 rv = (unsigned char *)&regs->dx;
257                 break;
258         case arg_AH:
259                 rv = 1 + (unsigned char *)&regs->ax;
260                 break;
261         case arg_BH:
262                 rv = 1 + (unsigned char *)&regs->bx;
263                 break;
264         case arg_CH:
265                 rv = 1 + (unsigned char *)&regs->cx;
266                 break;
267         case arg_DH:
268                 rv = 1 + (unsigned char *)&regs->dx;
269                 break;
270 #ifdef __amd64__
271         case arg_R8:
272                 rv = (unsigned char *)&regs->r8;
273                 break;
274         case arg_R9:
275                 rv = (unsigned char *)&regs->r9;
276                 break;
277         case arg_R10:
278                 rv = (unsigned char *)&regs->r10;
279                 break;
280         case arg_R11:
281                 rv = (unsigned char *)&regs->r11;
282                 break;
283         case arg_R12:
284                 rv = (unsigned char *)&regs->r12;
285                 break;
286         case arg_R13:
287                 rv = (unsigned char *)&regs->r13;
288                 break;
289         case arg_R14:
290                 rv = (unsigned char *)&regs->r14;
291                 break;
292         case arg_R15:
293                 rv = (unsigned char *)&regs->r15;
294                 break;
295 #endif
296         default:
297                 printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
298                 break;
299         }
300         return rv;
301 }
302
303 static unsigned long *get_reg_w32(int no, struct pt_regs *regs)
304 {
305         unsigned long *rv = NULL;
306
307         switch (no) {
308         case arg_AX:
309                 rv = &regs->ax;
310                 break;
311         case arg_BX:
312                 rv = &regs->bx;
313                 break;
314         case arg_CX:
315                 rv = &regs->cx;
316                 break;
317         case arg_DX:
318                 rv = &regs->dx;
319                 break;
320         case arg_SP:
321                 rv = &regs->sp;
322                 break;
323         case arg_BP:
324                 rv = &regs->bp;
325                 break;
326         case arg_SI:
327                 rv = &regs->si;
328                 break;
329         case arg_DI:
330                 rv = &regs->di;
331                 break;
332 #ifdef __amd64__
333         case arg_R8:
334                 rv = &regs->r8;
335                 break;
336         case arg_R9:
337                 rv = &regs->r9;
338                 break;
339         case arg_R10:
340                 rv = &regs->r10;
341                 break;
342         case arg_R11:
343                 rv = &regs->r11;
344                 break;
345         case arg_R12:
346                 rv = &regs->r12;
347                 break;
348         case arg_R13:
349                 rv = &regs->r13;
350                 break;
351         case arg_R14:
352                 rv = &regs->r14;
353                 break;
354         case arg_R15:
355                 rv = &regs->r15;
356                 break;
357 #endif
358         default:
359                 printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
360         }
361
362         return rv;
363 }
364
365 unsigned long get_ins_reg_val(unsigned long ins_addr, struct pt_regs *regs)
366 {
367         unsigned int opcode;
368         unsigned char mod_rm;
369         int reg;
370         unsigned char *p;
371         int i, shorted, enlarged, rexr;
372         unsigned long rv;
373
374         p = (unsigned char *)ins_addr;
375         p += skip_prefix(p, &shorted, &enlarged, &rexr);
376         p += get_opcode(p, &opcode);
377         for (i = 0; i < ARRAY_SIZE(reg_rop); i++)
378                 if (reg_rop[i] == opcode) {
379                         rv = REG_READ;
380                         goto do_work;
381                 }
382
383         for (i = 0; i < ARRAY_SIZE(reg_wop); i++)
384                 if (reg_wop[i] == opcode) {
385                         rv = REG_WRITE;
386                         goto do_work;
387                 }
388
389         printk(KERN_ERR "mmiotrace: Not a register instruction, opcode "
390                                                         "0x%02x\n", opcode);
391         goto err;
392
393 do_work:
394         mod_rm = *p;
395         reg = ((mod_rm >> 3) & 0x7) | (rexr << 3);
396         switch (get_ins_reg_width(ins_addr)) {
397         case 1:
398                 return *get_reg_w8(reg, regs);
399
400         case 2:
401                 return *(unsigned short *)get_reg_w32(reg, regs);
402
403         case 4:
404                 return *(unsigned int *)get_reg_w32(reg, regs);
405
406 #ifdef __amd64__
407         case 8:
408                 return *(unsigned long *)get_reg_w32(reg, regs);
409 #endif
410
411         default:
412                 printk(KERN_ERR "mmiotrace: Error width# %d\n", reg);
413         }
414
415 err:
416         return 0;
417 }
418
419 unsigned long get_ins_imm_val(unsigned long ins_addr)
420 {
421         unsigned int opcode;
422         unsigned char mod_rm;
423         unsigned char mod;
424         unsigned char *p;
425         int i, shorted, enlarged, rexr;
426         unsigned long rv;
427
428         p = (unsigned char *)ins_addr;
429         p += skip_prefix(p, &shorted, &enlarged, &rexr);
430         p += get_opcode(p, &opcode);
431         for (i = 0; i < ARRAY_SIZE(imm_wop); i++)
432                 if (imm_wop[i] == opcode) {
433                         rv = IMM_WRITE;
434                         goto do_work;
435                 }
436
437         printk(KERN_ERR "mmiotrace: Not an immediate instruction, opcode "
438                                                         "0x%02x\n", opcode);
439         goto err;
440
441 do_work:
442         mod_rm = *p;
443         mod = mod_rm >> 6;
444         p++;
445         switch (mod) {
446         case 0:
447                 /* if r/m is 5 we have a 32 disp (IA32 Manual 3, Table 2-2)  */
448                 /* AMD64: XXX Check for address size prefix? */
449                 if ((mod_rm & 0x7) == 0x5)
450                         p += 4;
451                 break;
452
453         case 1:
454                 p += 1;
455                 break;
456
457         case 2:
458                 p += 4;
459                 break;
460
461         case 3:
462         default:
463                 printk(KERN_ERR "mmiotrace: not a memory access instruction "
464                                                 "at 0x%lx, rm_mod=0x%02x\n",
465                                                 ins_addr, mod_rm);
466         }
467
468         switch (get_ins_reg_width(ins_addr)) {
469         case 1:
470                 return *(unsigned char *)p;
471
472         case 2:
473                 return *(unsigned short *)p;
474
475         case 4:
476                 return *(unsigned int *)p;
477
478 #ifdef __amd64__
479         case 8:
480                 return *(unsigned long *)p;
481 #endif
482
483         default:
484                 printk(KERN_ERR "mmiotrace: Error: width.\n");
485         }
486
487 err:
488         return 0;
489 }