1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3
4 #include <linux/audit.h>
5 #include <linux/elf.h>
6 #include <linux/errno.h>
7 #include <linux/kernel.h>
8 #include <linux/mm.h>
9 #include <linux/ptrace.h>
10 #include <linux/regset.h>
11 #include <linux/sched.h>
12 #include <linux/sched/task_stack.h>
13 #include <linux/signal.h>
14 #include <linux/smp.h>
15 #include <linux/tracehook.h>
16 #include <linux/uaccess.h>
17 #include <linux/user.h>
18
19 #include <asm/thread_info.h>
20 #include <asm/page.h>
21 #include <asm/processor.h>
22 #include <asm/asm-offsets.h>
23
24 #include <abi/regdef.h>
25 #include <abi/ckmmu.h>
26
27 #define CREATE_TRACE_POINTS
28 #include <trace/events/syscalls.h>
29
30 /* sets the trace bits. */
31 #define TRACE_MODE_SI (1 << 14)
32 #define TRACE_MODE_RUN 0
33 #define TRACE_MODE_MASK ~(0x3 << 14)
34
35 /*
36 * Make sure the single step bit is not set.
37 */
singlestep_disable(struct task_struct * tsk)38 static void singlestep_disable(struct task_struct *tsk)
39 {
40 struct pt_regs *regs;
41
42 regs = task_pt_regs(tsk);
43 regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_RUN;
44
45 /* Enable irq */
46 regs->sr |= BIT(6);
47 }
48
singlestep_enable(struct task_struct * tsk)49 static void singlestep_enable(struct task_struct *tsk)
50 {
51 struct pt_regs *regs;
52
53 regs = task_pt_regs(tsk);
54 regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_SI;
55
56 /* Disable irq */
57 regs->sr &= ~BIT(6);
58 }
59
60 /*
61 * Make sure the single step bit is set.
62 */
user_enable_single_step(struct task_struct * child)63 void user_enable_single_step(struct task_struct *child)
64 {
65 singlestep_enable(child);
66 }
67
user_disable_single_step(struct task_struct * child)68 void user_disable_single_step(struct task_struct *child)
69 {
70 singlestep_disable(child);
71 }
72
73 enum csky_regset {
74 REGSET_GPR,
75 REGSET_FPR,
76 };
77
gpr_get(struct task_struct * target,const struct user_regset * regset,struct membuf to)78 static int gpr_get(struct task_struct *target,
79 const struct user_regset *regset,
80 struct membuf to)
81 {
82 struct pt_regs *regs = task_pt_regs(target);
83
84 /* Abiv1 regs->tls is fake and we need sync here. */
85 regs->tls = task_thread_info(target)->tp_value;
86
87 return membuf_write(&to, regs, sizeof(*regs));
88 }
89
gpr_set(struct task_struct * target,const struct user_regset * regset,unsigned int pos,unsigned int count,const void * kbuf,const void __user * ubuf)90 static int gpr_set(struct task_struct *target,
91 const struct user_regset *regset,
92 unsigned int pos, unsigned int count,
93 const void *kbuf, const void __user *ubuf)
94 {
95 int ret;
96 struct pt_regs regs;
97
98 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, ®s, 0, -1);
99 if (ret)
100 return ret;
101
102 /* BIT(0) of regs.sr is Condition Code/Carry bit */
103 regs.sr = (regs.sr & BIT(0)) | (task_pt_regs(target)->sr & ~BIT(0));
104 #ifdef CONFIG_CPU_HAS_HILO
105 regs.dcsr = task_pt_regs(target)->dcsr;
106 #endif
107 task_thread_info(target)->tp_value = regs.tls;
108
109 *task_pt_regs(target) = regs;
110
111 return 0;
112 }
113
fpr_get(struct task_struct * target,const struct user_regset * regset,struct membuf to)114 static int fpr_get(struct task_struct *target,
115 const struct user_regset *regset,
116 struct membuf to)
117 {
118 struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
119
120 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
121 int i;
122 struct user_fp tmp = *regs;
123
124 for (i = 0; i < 16; i++) {
125 tmp.vr[i*4] = regs->vr[i*2];
126 tmp.vr[i*4 + 1] = regs->vr[i*2 + 1];
127 }
128
129 for (i = 0; i < 32; i++)
130 tmp.vr[64 + i] = regs->vr[32 + i];
131
132 return membuf_write(&to, &tmp, sizeof(tmp));
133 #else
134 return membuf_write(&to, regs, sizeof(*regs));
135 #endif
136 }
137
fpr_set(struct task_struct * target,const struct user_regset * regset,unsigned int pos,unsigned int count,const void * kbuf,const void __user * ubuf)138 static int fpr_set(struct task_struct *target,
139 const struct user_regset *regset,
140 unsigned int pos, unsigned int count,
141 const void *kbuf, const void __user *ubuf)
142 {
143 int ret;
144 struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
145
146 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
147 int i;
148 struct user_fp tmp;
149
150 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);
151
152 *regs = tmp;
153
154 for (i = 0; i < 16; i++) {
155 regs->vr[i*2] = tmp.vr[i*4];
156 regs->vr[i*2 + 1] = tmp.vr[i*4 + 1];
157 }
158
159 for (i = 0; i < 32; i++)
160 regs->vr[32 + i] = tmp.vr[64 + i];
161 #else
162 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
163 #endif
164
165 return ret;
166 }
167
168 static const struct user_regset csky_regsets[] = {
169 [REGSET_GPR] = {
170 .core_note_type = NT_PRSTATUS,
171 .n = sizeof(struct pt_regs) / sizeof(u32),
172 .size = sizeof(u32),
173 .align = sizeof(u32),
174 .regset_get = gpr_get,
175 .set = gpr_set,
176 },
177 [REGSET_FPR] = {
178 .core_note_type = NT_PRFPREG,
179 .n = sizeof(struct user_fp) / sizeof(u32),
180 .size = sizeof(u32),
181 .align = sizeof(u32),
182 .regset_get = fpr_get,
183 .set = fpr_set,
184 },
185 };
186
187 static const struct user_regset_view user_csky_view = {
188 .name = "csky",
189 .e_machine = ELF_ARCH,
190 .regsets = csky_regsets,
191 .n = ARRAY_SIZE(csky_regsets),
192 };
193
task_user_regset_view(struct task_struct * task)194 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
195 {
196 return &user_csky_view;
197 }
198
199 struct pt_regs_offset {
200 const char *name;
201 int offset;
202 };
203
204 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
205 #define REG_OFFSET_END {.name = NULL, .offset = 0}
206
207 static const struct pt_regs_offset regoffset_table[] = {
208 REG_OFFSET_NAME(tls),
209 REG_OFFSET_NAME(lr),
210 REG_OFFSET_NAME(pc),
211 REG_OFFSET_NAME(sr),
212 REG_OFFSET_NAME(usp),
213 REG_OFFSET_NAME(orig_a0),
214 REG_OFFSET_NAME(a0),
215 REG_OFFSET_NAME(a1),
216 REG_OFFSET_NAME(a2),
217 REG_OFFSET_NAME(a3),
218 REG_OFFSET_NAME(regs[0]),
219 REG_OFFSET_NAME(regs[1]),
220 REG_OFFSET_NAME(regs[2]),
221 REG_OFFSET_NAME(regs[3]),
222 REG_OFFSET_NAME(regs[4]),
223 REG_OFFSET_NAME(regs[5]),
224 REG_OFFSET_NAME(regs[6]),
225 REG_OFFSET_NAME(regs[7]),
226 REG_OFFSET_NAME(regs[8]),
227 REG_OFFSET_NAME(regs[9]),
228 #if defined(__CSKYABIV2__)
229 REG_OFFSET_NAME(exregs[0]),
230 REG_OFFSET_NAME(exregs[1]),
231 REG_OFFSET_NAME(exregs[2]),
232 REG_OFFSET_NAME(exregs[3]),
233 REG_OFFSET_NAME(exregs[4]),
234 REG_OFFSET_NAME(exregs[5]),
235 REG_OFFSET_NAME(exregs[6]),
236 REG_OFFSET_NAME(exregs[7]),
237 REG_OFFSET_NAME(exregs[8]),
238 REG_OFFSET_NAME(exregs[9]),
239 REG_OFFSET_NAME(exregs[10]),
240 REG_OFFSET_NAME(exregs[11]),
241 REG_OFFSET_NAME(exregs[12]),
242 REG_OFFSET_NAME(exregs[13]),
243 REG_OFFSET_NAME(exregs[14]),
244 REG_OFFSET_NAME(rhi),
245 REG_OFFSET_NAME(rlo),
246 REG_OFFSET_NAME(dcsr),
247 #endif
248 REG_OFFSET_END,
249 };
250
251 /**
252 * regs_query_register_offset() - query register offset from its name
253 * @name: the name of a register
254 *
255 * regs_query_register_offset() returns the offset of a register in struct
256 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
257 */
regs_query_register_offset(const char * name)258 int regs_query_register_offset(const char *name)
259 {
260 const struct pt_regs_offset *roff;
261
262 for (roff = regoffset_table; roff->name != NULL; roff++)
263 if (!strcmp(roff->name, name))
264 return roff->offset;
265 return -EINVAL;
266 }
267
268 /**
269 * regs_within_kernel_stack() - check the address in the stack
270 * @regs: pt_regs which contains kernel stack pointer.
271 * @addr: address which is checked.
272 *
273 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
274 * If @addr is within the kernel stack, it returns true. If not, returns false.
275 */
regs_within_kernel_stack(struct pt_regs * regs,unsigned long addr)276 static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
277 {
278 return (addr & ~(THREAD_SIZE - 1)) ==
279 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1));
280 }
281
282 /**
283 * regs_get_kernel_stack_nth() - get Nth entry of the stack
284 * @regs: pt_regs which contains kernel stack pointer.
285 * @n: stack entry number.
286 *
287 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
288 * is specified by @regs. If the @n th entry is NOT in the kernel stack,
289 * this returns 0.
290 */
regs_get_kernel_stack_nth(struct pt_regs * regs,unsigned int n)291 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
292 {
293 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
294
295 addr += n;
296 if (regs_within_kernel_stack(regs, (unsigned long)addr))
297 return *addr;
298 else
299 return 0;
300 }
301
ptrace_disable(struct task_struct * child)302 void ptrace_disable(struct task_struct *child)
303 {
304 singlestep_disable(child);
305 }
306
arch_ptrace(struct task_struct * child,long request,unsigned long addr,unsigned long data)307 long arch_ptrace(struct task_struct *child, long request,
308 unsigned long addr, unsigned long data)
309 {
310 long ret = -EIO;
311
312 switch (request) {
313 default:
314 ret = ptrace_request(child, request, addr, data);
315 break;
316 }
317
318 return ret;
319 }
320
syscall_trace_enter(struct pt_regs * regs)321 asmlinkage int syscall_trace_enter(struct pt_regs *regs)
322 {
323 if (test_thread_flag(TIF_SYSCALL_TRACE))
324 if (tracehook_report_syscall_entry(regs))
325 return -1;
326
327 if (secure_computing() == -1)
328 return -1;
329
330 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
331 trace_sys_enter(regs, syscall_get_nr(current, regs));
332
333 audit_syscall_entry(regs_syscallid(regs), regs->a0, regs->a1, regs->a2, regs->a3);
334 return 0;
335 }
336
syscall_trace_exit(struct pt_regs * regs)337 asmlinkage void syscall_trace_exit(struct pt_regs *regs)
338 {
339 audit_syscall_exit(regs);
340
341 if (test_thread_flag(TIF_SYSCALL_TRACE))
342 tracehook_report_syscall_exit(regs, 0);
343
344 if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
345 trace_sys_exit(regs, syscall_get_return_value(current, regs));
346 }
347
348 #ifdef CONFIG_CPU_CK860
show_iutlb(void)349 static void show_iutlb(void)
350 {
351 int entry, i;
352 unsigned long flags;
353 unsigned long oldpid;
354 unsigned long entryhi[16], entrylo0[16], entrylo1[16];
355
356 oldpid = read_mmu_entryhi();
357
358 entry = 0x8000;
359
360 local_irq_save(flags);
361
362 for (i = 0; i < 16; i++) {
363 write_mmu_index(entry);
364 tlb_read();
365 entryhi[i] = read_mmu_entryhi();
366 entrylo0[i] = read_mmu_entrylo0();
367 entrylo1[i] = read_mmu_entrylo1();
368
369 entry++;
370 }
371
372 local_irq_restore(flags);
373
374 write_mmu_entryhi(oldpid);
375
376 printk("\n\n\n");
377 for (i = 0; i < 16; i++)
378 printk("iutlb[%d]: entryhi - 0x%lx; entrylo0 - 0x%lx;"
379 " entrylo1 - 0x%lx\n",
380 i, entryhi[i], entrylo0[i], entrylo1[i]);
381 printk("\n\n\n");
382 }
383
show_dutlb(void)384 static void show_dutlb(void)
385 {
386 int entry, i;
387 unsigned long flags;
388 unsigned long oldpid;
389 unsigned long entryhi[16], entrylo0[16], entrylo1[16];
390
391 oldpid = read_mmu_entryhi();
392
393 entry = 0x4000;
394
395 local_irq_save(flags);
396
397 for (i = 0; i < 16; i++) {
398 write_mmu_index(entry);
399 tlb_read();
400 entryhi[i] = read_mmu_entryhi();
401 entrylo0[i] = read_mmu_entrylo0();
402 entrylo1[i] = read_mmu_entrylo1();
403
404 entry++;
405 }
406
407 local_irq_restore(flags);
408
409 write_mmu_entryhi(oldpid);
410
411 printk("\n\n\n");
412 for (i = 0; i < 16; i++)
413 printk("dutlb[%d]: entryhi - 0x%lx; entrylo0 - 0x%lx;"
414 " entrylo1 - 0x%lx\n",
415 i, entryhi[i], entrylo0[i], entrylo1[i]);
416 printk("\n\n\n");
417 }
418
419 static unsigned long entryhi[1024], entrylo0[1024], entrylo1[1024];
show_jtlb(void)420 static void show_jtlb(void)
421 {
422 int entry;
423 unsigned long flags;
424 unsigned long oldpid;
425
426 oldpid = read_mmu_entryhi();
427
428 entry = 0;
429
430 local_irq_save(flags);
431 while (entry < 1024) {
432 write_mmu_index(entry);
433 tlb_read();
434 entryhi[entry] = read_mmu_entryhi();
435 entrylo0[entry] = read_mmu_entrylo0();
436 entrylo1[entry] = read_mmu_entrylo1();
437
438 entry++;
439 }
440 local_irq_restore(flags);
441
442 write_mmu_entryhi(oldpid);
443
444 printk("\n\n\n");
445
446 for (entry = 0; entry < 1024; entry++)
447 printk("jtlb[%x]: entryhi - 0x%lx; entrylo0 - 0x%lx;"
448 " entrylo1 - 0x%lx\n",
449 entry, entryhi[entry], entrylo0[entry], entrylo1[entry]);
450 printk("\n\n\n");
451 }
452
show_tlb(void)453 static void show_tlb(void)
454 {
455 show_iutlb();
456 show_dutlb();
457 show_jtlb();
458 }
459 #else
show_tlb(void)460 static void show_tlb(void)
461 {
462 return;
463 }
464 #endif
465
show_regs(struct pt_regs * fp)466 void show_regs(struct pt_regs *fp)
467 {
468 pr_info("\nCURRENT PROCESS:\n\n");
469 pr_info("COMM=%s PID=%d\n", current->comm, current->pid);
470
471 if (current->mm) {
472 pr_info("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
473 (int) current->mm->start_code,
474 (int) current->mm->end_code,
475 (int) current->mm->start_data,
476 (int) current->mm->end_data,
477 (int) current->mm->end_data,
478 (int) current->mm->brk);
479 pr_info("USER-STACK=%08x KERNEL-STACK=%08x\n\n",
480 (int) current->mm->start_stack,
481 (int) (((unsigned long) current) + 2 * PAGE_SIZE));
482 }
483
484 pr_info("PC: 0x%08lx (%pS)\n", (long)fp->pc, (void *)fp->pc);
485 pr_info("LR: 0x%08lx (%pS)\n", (long)fp->lr, (void *)fp->lr);
486 pr_info("SP: 0x%08lx\n", (long)fp->usp);
487 pr_info("PSR: 0x%08lx\n", (long)fp->sr);
488 pr_info("orig_a0: 0x%08lx\n", fp->orig_a0);
489 pr_info("PT_REGS: 0x%08lx\n", (long)fp);
490
491 pr_info(" a0: 0x%08lx a1: 0x%08lx a2: 0x%08lx a3: 0x%08lx\n",
492 fp->a0, fp->a1, fp->a2, fp->a3);
493 #if defined(__CSKYABIV2__)
494 pr_info(" r4: 0x%08lx r5: 0x%08lx r6: 0x%08lx r7: 0x%08lx\n",
495 fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
496 pr_info(" r8: 0x%08lx r9: 0x%08lx r10: 0x%08lx r11: 0x%08lx\n",
497 fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
498 pr_info("r12: 0x%08lx r13: 0x%08lx r15: 0x%08lx\n",
499 fp->regs[8], fp->regs[9], fp->lr);
500 pr_info("r16: 0x%08lx r17: 0x%08lx r18: 0x%08lx r19: 0x%08lx\n",
501 fp->exregs[0], fp->exregs[1], fp->exregs[2], fp->exregs[3]);
502 pr_info("r20: 0x%08lx r21: 0x%08lx r22: 0x%08lx r23: 0x%08lx\n",
503 fp->exregs[4], fp->exregs[5], fp->exregs[6], fp->exregs[7]);
504 pr_info("r24: 0x%08lx r25: 0x%08lx r26: 0x%08lx r27: 0x%08lx\n",
505 fp->exregs[8], fp->exregs[9], fp->exregs[10], fp->exregs[11]);
506 pr_info("r28: 0x%08lx r29: 0x%08lx r30: 0x%08lx tls: 0x%08lx\n",
507 fp->exregs[12], fp->exregs[13], fp->exregs[14], fp->tls);
508 pr_info(" hi: 0x%08lx lo: 0x%08lx\n",
509 fp->rhi, fp->rlo);
510 #else
511 pr_info(" r6: 0x%08lx r7: 0x%08lx r8: 0x%08lx r9: 0x%08lx\n",
512 fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
513 pr_info("r10: 0x%08lx r11: 0x%08lx r12: 0x%08lx r13: 0x%08lx\n",
514 fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
515 pr_info("r14: 0x%08lx r1: 0x%08lx\n",
516 fp->regs[8], fp->regs[9]);
517 #endif
518
519 show_tlb();
520
521 return;
522 }
523