Merge tag 'for-5.9-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave...
[linux-2.6-microblaze.git] / arch / csky / kernel / ptrace.c
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
26 #define CREATE_TRACE_POINTS
27 #include <trace/events/syscalls.h>
28
29 /* sets the trace bits. */
30 #define TRACE_MODE_SI      (1 << 14)
31 #define TRACE_MODE_RUN     0
32 #define TRACE_MODE_MASK    ~(0x3 << 14)
33
34 /*
35  * Make sure the single step bit is not set.
36  */
37 static void singlestep_disable(struct task_struct *tsk)
38 {
39         struct pt_regs *regs;
40
41         regs = task_pt_regs(tsk);
42         regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_RUN;
43
44         /* Enable irq */
45         regs->sr |= BIT(6);
46 }
47
48 static void singlestep_enable(struct task_struct *tsk)
49 {
50         struct pt_regs *regs;
51
52         regs = task_pt_regs(tsk);
53         regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_SI;
54
55         /* Disable irq */
56         regs->sr &= ~BIT(6);
57 }
58
59 /*
60  * Make sure the single step bit is set.
61  */
62 void user_enable_single_step(struct task_struct *child)
63 {
64         singlestep_enable(child);
65 }
66
67 void user_disable_single_step(struct task_struct *child)
68 {
69         singlestep_disable(child);
70 }
71
72 enum csky_regset {
73         REGSET_GPR,
74         REGSET_FPR,
75 };
76
77 static int gpr_get(struct task_struct *target,
78                    const struct user_regset *regset,
79                    struct membuf to)
80 {
81         struct pt_regs *regs = task_pt_regs(target);
82
83         /* Abiv1 regs->tls is fake and we need sync here. */
84         regs->tls = task_thread_info(target)->tp_value;
85
86         return membuf_write(&to, regs, sizeof(regs));
87 }
88
89 static int gpr_set(struct task_struct *target,
90                     const struct user_regset *regset,
91                     unsigned int pos, unsigned int count,
92                     const void *kbuf, const void __user *ubuf)
93 {
94         int ret;
95         struct pt_regs regs;
96
97         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &regs, 0, -1);
98         if (ret)
99                 return ret;
100
101         regs.sr = task_pt_regs(target)->sr;
102 #ifdef CONFIG_CPU_HAS_HILO
103         regs.dcsr = task_pt_regs(target)->dcsr;
104 #endif
105         task_thread_info(target)->tp_value = regs.tls;
106
107         *task_pt_regs(target) = regs;
108
109         return 0;
110 }
111
112 static int fpr_get(struct task_struct *target,
113                    const struct user_regset *regset,
114                    struct membuf to)
115 {
116         struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
117
118 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
119         int i;
120         struct user_fp tmp = *regs;
121
122         for (i = 0; i < 16; i++) {
123                 tmp.vr[i*4] = regs->vr[i*2];
124                 tmp.vr[i*4 + 1] = regs->vr[i*2 + 1];
125         }
126
127         for (i = 0; i < 32; i++)
128                 tmp.vr[64 + i] = regs->vr[32 + i];
129
130         return membuf_write(&to, &tmp, sizeof(tmp));
131 #else
132         return membuf_write(&to, regs, sizeof(*regs));
133 #endif
134 }
135
136 static int fpr_set(struct task_struct *target,
137                    const struct user_regset *regset,
138                    unsigned int pos, unsigned int count,
139                    const void *kbuf, const void __user *ubuf)
140 {
141         int ret;
142         struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
143
144 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
145         int i;
146         struct user_fp tmp;
147
148         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);
149
150         *regs = tmp;
151
152         for (i = 0; i < 16; i++) {
153                 regs->vr[i*2] = tmp.vr[i*4];
154                 regs->vr[i*2 + 1] = tmp.vr[i*4 + 1];
155         }
156
157         for (i = 0; i < 32; i++)
158                 regs->vr[32 + i] = tmp.vr[64 + i];
159 #else
160         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
161 #endif
162
163         return ret;
164 }
165
166 static const struct user_regset csky_regsets[] = {
167         [REGSET_GPR] = {
168                 .core_note_type = NT_PRSTATUS,
169                 .n = sizeof(struct pt_regs) / sizeof(u32),
170                 .size = sizeof(u32),
171                 .align = sizeof(u32),
172                 .regset_get = gpr_get,
173                 .set = gpr_set,
174         },
175         [REGSET_FPR] = {
176                 .core_note_type = NT_PRFPREG,
177                 .n = sizeof(struct user_fp) / sizeof(u32),
178                 .size = sizeof(u32),
179                 .align = sizeof(u32),
180                 .regset_get = fpr_get,
181                 .set = fpr_set,
182         },
183 };
184
185 static const struct user_regset_view user_csky_view = {
186         .name = "csky",
187         .e_machine = ELF_ARCH,
188         .regsets = csky_regsets,
189         .n = ARRAY_SIZE(csky_regsets),
190 };
191
192 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
193 {
194         return &user_csky_view;
195 }
196
197 struct pt_regs_offset {
198         const char *name;
199         int offset;
200 };
201
202 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
203 #define REG_OFFSET_END {.name = NULL, .offset = 0}
204
205 static const struct pt_regs_offset regoffset_table[] = {
206         REG_OFFSET_NAME(tls),
207         REG_OFFSET_NAME(lr),
208         REG_OFFSET_NAME(pc),
209         REG_OFFSET_NAME(sr),
210         REG_OFFSET_NAME(usp),
211         REG_OFFSET_NAME(orig_a0),
212         REG_OFFSET_NAME(a0),
213         REG_OFFSET_NAME(a1),
214         REG_OFFSET_NAME(a2),
215         REG_OFFSET_NAME(a3),
216         REG_OFFSET_NAME(regs[0]),
217         REG_OFFSET_NAME(regs[1]),
218         REG_OFFSET_NAME(regs[2]),
219         REG_OFFSET_NAME(regs[3]),
220         REG_OFFSET_NAME(regs[4]),
221         REG_OFFSET_NAME(regs[5]),
222         REG_OFFSET_NAME(regs[6]),
223         REG_OFFSET_NAME(regs[7]),
224         REG_OFFSET_NAME(regs[8]),
225         REG_OFFSET_NAME(regs[9]),
226 #if defined(__CSKYABIV2__)
227         REG_OFFSET_NAME(exregs[0]),
228         REG_OFFSET_NAME(exregs[1]),
229         REG_OFFSET_NAME(exregs[2]),
230         REG_OFFSET_NAME(exregs[3]),
231         REG_OFFSET_NAME(exregs[4]),
232         REG_OFFSET_NAME(exregs[5]),
233         REG_OFFSET_NAME(exregs[6]),
234         REG_OFFSET_NAME(exregs[7]),
235         REG_OFFSET_NAME(exregs[8]),
236         REG_OFFSET_NAME(exregs[9]),
237         REG_OFFSET_NAME(exregs[10]),
238         REG_OFFSET_NAME(exregs[11]),
239         REG_OFFSET_NAME(exregs[12]),
240         REG_OFFSET_NAME(exregs[13]),
241         REG_OFFSET_NAME(exregs[14]),
242         REG_OFFSET_NAME(rhi),
243         REG_OFFSET_NAME(rlo),
244         REG_OFFSET_NAME(dcsr),
245 #endif
246         REG_OFFSET_END,
247 };
248
249 /**
250  * regs_query_register_offset() - query register offset from its name
251  * @name:       the name of a register
252  *
253  * regs_query_register_offset() returns the offset of a register in struct
254  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
255  */
256 int regs_query_register_offset(const char *name)
257 {
258         const struct pt_regs_offset *roff;
259
260         for (roff = regoffset_table; roff->name != NULL; roff++)
261                 if (!strcmp(roff->name, name))
262                         return roff->offset;
263         return -EINVAL;
264 }
265
266 /**
267  * regs_within_kernel_stack() - check the address in the stack
268  * @regs:      pt_regs which contains kernel stack pointer.
269  * @addr:      address which is checked.
270  *
271  * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
272  * If @addr is within the kernel stack, it returns true. If not, returns false.
273  */
274 static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
275 {
276         return (addr & ~(THREAD_SIZE - 1))  ==
277                 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1));
278 }
279
280 /**
281  * regs_get_kernel_stack_nth() - get Nth entry of the stack
282  * @regs:       pt_regs which contains kernel stack pointer.
283  * @n:          stack entry number.
284  *
285  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
286  * is specified by @regs. If the @n th entry is NOT in the kernel stack,
287  * this returns 0.
288  */
289 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
290 {
291         unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
292
293         addr += n;
294         if (regs_within_kernel_stack(regs, (unsigned long)addr))
295                 return *addr;
296         else
297                 return 0;
298 }
299
300 void ptrace_disable(struct task_struct *child)
301 {
302         singlestep_disable(child);
303 }
304
305 long arch_ptrace(struct task_struct *child, long request,
306                  unsigned long addr, unsigned long data)
307 {
308         long ret = -EIO;
309
310         switch (request) {
311         default:
312                 ret = ptrace_request(child, request, addr, data);
313                 break;
314         }
315
316         return ret;
317 }
318
319 asmlinkage int syscall_trace_enter(struct pt_regs *regs)
320 {
321         if (test_thread_flag(TIF_SYSCALL_TRACE))
322                 if (tracehook_report_syscall_entry(regs))
323                         return -1;
324
325         if (secure_computing() == -1)
326                 return -1;
327
328         if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
329                 trace_sys_enter(regs, syscall_get_nr(current, regs));
330
331         audit_syscall_entry(regs_syscallid(regs), regs->a0, regs->a1, regs->a2, regs->a3);
332         return 0;
333 }
334
335 asmlinkage void syscall_trace_exit(struct pt_regs *regs)
336 {
337         audit_syscall_exit(regs);
338
339         if (test_thread_flag(TIF_SYSCALL_TRACE))
340                 tracehook_report_syscall_exit(regs, 0);
341
342         if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
343                 trace_sys_exit(regs, syscall_get_return_value(current, regs));
344 }
345
346 void show_regs(struct pt_regs *fp)
347 {
348         pr_info("\nCURRENT PROCESS:\n\n");
349         pr_info("COMM=%s PID=%d\n", current->comm, current->pid);
350
351         if (current->mm) {
352                 pr_info("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
353                        (int) current->mm->start_code,
354                        (int) current->mm->end_code,
355                        (int) current->mm->start_data,
356                        (int) current->mm->end_data,
357                        (int) current->mm->end_data,
358                        (int) current->mm->brk);
359                 pr_info("USER-STACK=%08x  KERNEL-STACK=%08x\n\n",
360                        (int) current->mm->start_stack,
361                        (int) (((unsigned long) current) + 2 * PAGE_SIZE));
362         }
363
364         pr_info("PC: 0x%08lx (%pS)\n", (long)fp->pc, (void *)fp->pc);
365         pr_info("LR: 0x%08lx (%pS)\n", (long)fp->lr, (void *)fp->lr);
366         pr_info("SP: 0x%08lx\n", (long)fp);
367         pr_info("orig_a0: 0x%08lx\n", fp->orig_a0);
368         pr_info("PSR: 0x%08lx\n", (long)fp->sr);
369
370         pr_info(" a0: 0x%08lx   a1: 0x%08lx   a2: 0x%08lx   a3: 0x%08lx\n",
371                 fp->a0, fp->a1, fp->a2, fp->a3);
372 #if defined(__CSKYABIV2__)
373         pr_info(" r4: 0x%08lx   r5: 0x%08lx   r6: 0x%08lx   r7: 0x%08lx\n",
374                 fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
375         pr_info(" r8: 0x%08lx   r9: 0x%08lx  r10: 0x%08lx  r11: 0x%08lx\n",
376                 fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
377         pr_info("r12: 0x%08lx  r13: 0x%08lx  r15: 0x%08lx\n",
378                 fp->regs[8], fp->regs[9], fp->lr);
379         pr_info("r16: 0x%08lx  r17: 0x%08lx  r18: 0x%08lx  r19: 0x%08lx\n",
380                 fp->exregs[0], fp->exregs[1], fp->exregs[2], fp->exregs[3]);
381         pr_info("r20: 0x%08lx  r21: 0x%08lx  r22: 0x%08lx  r23: 0x%08lx\n",
382                 fp->exregs[4], fp->exregs[5], fp->exregs[6], fp->exregs[7]);
383         pr_info("r24: 0x%08lx  r25: 0x%08lx  r26: 0x%08lx  r27: 0x%08lx\n",
384                 fp->exregs[8], fp->exregs[9], fp->exregs[10], fp->exregs[11]);
385         pr_info("r28: 0x%08lx  r29: 0x%08lx  r30: 0x%08lx  tls: 0x%08lx\n",
386                 fp->exregs[12], fp->exregs[13], fp->exregs[14], fp->tls);
387         pr_info(" hi: 0x%08lx   lo: 0x%08lx\n",
388                 fp->rhi, fp->rlo);
389 #else
390         pr_info(" r6: 0x%08lx   r7: 0x%08lx   r8: 0x%08lx   r9: 0x%08lx\n",
391                 fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
392         pr_info("r10: 0x%08lx  r11: 0x%08lx  r12: 0x%08lx  r13: 0x%08lx\n",
393                 fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
394         pr_info("r14: 0x%08lx   r1: 0x%08lx\n",
395                 fp->regs[8], fp->regs[9]);
396 #endif
397
398         return;
399 }