Merge branch 'akpm' (patches from Andrew)
[sfrench/cifs-2.6.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/elf.h>
5 #include <linux/errno.h>
6 #include <linux/kernel.h>
7 #include <linux/mm.h>
8 #include <linux/ptrace.h>
9 #include <linux/regset.h>
10 #include <linux/sched.h>
11 #include <linux/signal.h>
12 #include <linux/smp.h>
13 #include <linux/uaccess.h>
14 #include <linux/user.h>
15
16 #include <asm/thread_info.h>
17 #include <asm/page.h>
18 #include <asm/pgtable.h>
19 #include <asm/processor.h>
20 #include <asm/asm-offsets.h>
21
22 #include <abi/regdef.h>
23
24 /* sets the trace bits. */
25 #define TRACE_MODE_SI      (1 << 14)
26 #define TRACE_MODE_RUN     0
27 #define TRACE_MODE_MASK    ~(0x3 << 14)
28
29 /*
30  * Make sure the single step bit is not set.
31  */
32 static void singlestep_disable(struct task_struct *tsk)
33 {
34         struct pt_regs *regs;
35
36         regs = task_pt_regs(tsk);
37         regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_RUN;
38 }
39
40 static void singlestep_enable(struct task_struct *tsk)
41 {
42         struct pt_regs *regs;
43
44         regs = task_pt_regs(tsk);
45         regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_SI;
46 }
47
48 /*
49  * Make sure the single step bit is set.
50  */
51 void user_enable_single_step(struct task_struct *child)
52 {
53         if (child->thread.esp0 == 0)
54                 return;
55         singlestep_enable(child);
56 }
57
58 void user_disable_single_step(struct task_struct *child)
59 {
60         if (child->thread.esp0 == 0)
61                 return;
62         singlestep_disable(child);
63 }
64
65 enum csky_regset {
66         REGSET_GPR,
67         REGSET_FPR,
68 };
69
70 static int gpr_get(struct task_struct *target,
71                    const struct user_regset *regset,
72                    unsigned int pos, unsigned int count,
73                    void *kbuf, void __user *ubuf)
74 {
75         struct pt_regs *regs;
76
77         regs = task_pt_regs(target);
78
79         /* Abiv1 regs->tls is fake and we need sync here. */
80         regs->tls = task_thread_info(target)->tp_value;
81
82         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
83 }
84
85 static int gpr_set(struct task_struct *target,
86                     const struct user_regset *regset,
87                     unsigned int pos, unsigned int count,
88                     const void *kbuf, const void __user *ubuf)
89 {
90         int ret;
91         struct pt_regs regs;
92
93         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &regs, 0, -1);
94         if (ret)
95                 return ret;
96
97         regs.sr = task_pt_regs(target)->sr;
98
99         task_thread_info(target)->tp_value = regs.tls;
100
101         *task_pt_regs(target) = regs;
102
103         return 0;
104 }
105
106 static int fpr_get(struct task_struct *target,
107                    const struct user_regset *regset,
108                    unsigned int pos, unsigned int count,
109                    void *kbuf, void __user *ubuf)
110 {
111         struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
112
113 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
114         int i;
115         struct user_fp tmp = *regs;
116
117         for (i = 0; i < 16; i++) {
118                 tmp.vr[i*4] = regs->vr[i*2];
119                 tmp.vr[i*4 + 1] = regs->vr[i*2 + 1];
120         }
121
122         for (i = 0; i < 32; i++)
123                 tmp.vr[64 + i] = regs->vr[32 + i];
124
125         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);
126 #else
127         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
128 #endif
129 }
130
131 static int fpr_set(struct task_struct *target,
132                    const struct user_regset *regset,
133                    unsigned int pos, unsigned int count,
134                    const void *kbuf, const void __user *ubuf)
135 {
136         int ret;
137         struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
138
139 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
140         int i;
141         struct user_fp tmp;
142
143         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);
144
145         *regs = tmp;
146
147         for (i = 0; i < 16; i++) {
148                 regs->vr[i*2] = tmp.vr[i*4];
149                 regs->vr[i*2 + 1] = tmp.vr[i*4 + 1];
150         }
151
152         for (i = 0; i < 32; i++)
153                 regs->vr[32 + i] = tmp.vr[64 + i];
154 #else
155         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
156 #endif
157
158         return ret;
159 }
160
161 static const struct user_regset csky_regsets[] = {
162         [REGSET_GPR] = {
163                 .core_note_type = NT_PRSTATUS,
164                 .n = ELF_NGREG,
165                 .size = sizeof(u32),
166                 .align = sizeof(u32),
167                 .get = &gpr_get,
168                 .set = &gpr_set,
169         },
170         [REGSET_FPR] = {
171                 .core_note_type = NT_PRFPREG,
172                 .n = sizeof(struct user_fp) / sizeof(u32),
173                 .size = sizeof(u32),
174                 .align = sizeof(u32),
175                 .get = &fpr_get,
176                 .set = &fpr_set,
177         },
178 };
179
180 static const struct user_regset_view user_csky_view = {
181         .name = "csky",
182         .e_machine = ELF_ARCH,
183         .regsets = csky_regsets,
184         .n = ARRAY_SIZE(csky_regsets),
185 };
186
187 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
188 {
189         return &user_csky_view;
190 }
191
192 void ptrace_disable(struct task_struct *child)
193 {
194         singlestep_disable(child);
195 }
196
197 long arch_ptrace(struct task_struct *child, long request,
198                  unsigned long addr, unsigned long data)
199 {
200         long ret = -EIO;
201
202         switch (request) {
203         default:
204                 ret = ptrace_request(child, request, addr, data);
205                 break;
206         }
207
208         return ret;
209 }
210
211 /*
212  * If process's system calls is traces, do some corresponding handles in this
213  * function before entering system call function and after exiting system call
214  * function.
215  */
216 asmlinkage void syscall_trace(int why, struct pt_regs *regs)
217 {
218         long saved_why;
219         /*
220          * Save saved_why, why is used to denote syscall entry/exit;
221          * why = 0:entry, why = 1: exit
222          */
223         saved_why = regs->regs[SYSTRACE_SAVENUM];
224         regs->regs[SYSTRACE_SAVENUM] = why;
225
226         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
227                                         ? 0x80 : 0));
228
229         /*
230          * this isn't the same as continuing with a signal, but it will do
231          * for normal use.  strace only continues with a signal if the
232          * stopping signal is not SIGTRAP.  -brl
233          */
234         if (current->exit_code) {
235                 send_sig(current->exit_code, current, 1);
236                 current->exit_code = 0;
237         }
238
239         regs->regs[SYSTRACE_SAVENUM] = saved_why;
240 }
241
242 void show_regs(struct pt_regs *fp)
243 {
244         unsigned long   *sp;
245         unsigned char   *tp;
246         int     i;
247
248         pr_info("\nCURRENT PROCESS:\n\n");
249         pr_info("COMM=%s PID=%d\n", current->comm, current->pid);
250
251         if (current->mm) {
252                 pr_info("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
253                        (int) current->mm->start_code,
254                        (int) current->mm->end_code,
255                        (int) current->mm->start_data,
256                        (int) current->mm->end_data,
257                        (int) current->mm->end_data,
258                        (int) current->mm->brk);
259                 pr_info("USER-STACK=%08x  KERNEL-STACK=%08x\n\n",
260                        (int) current->mm->start_stack,
261                        (int) (((unsigned long) current) + 2 * PAGE_SIZE));
262         }
263
264         pr_info("PC: 0x%08lx\n", (long)fp->pc);
265         pr_info("orig_a0: 0x%08lx\n", fp->orig_a0);
266         pr_info("PSR: 0x%08lx\n", (long)fp->sr);
267
268         pr_info("a0: 0x%08lx  a1: 0x%08lx  a2: 0x%08lx  a3: 0x%08lx\n",
269                fp->a0, fp->a1, fp->a2, fp->a3);
270 #if defined(__CSKYABIV2__)
271         pr_info("r4: 0x%08lx  r5: 0x%08lx    r6: 0x%08lx    r7: 0x%08lx\n",
272                 fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
273         pr_info("r8: 0x%08lx  r9: 0x%08lx   r10: 0x%08lx   r11: 0x%08lx\n",
274                 fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
275         pr_info("r12 0x%08lx  r13: 0x%08lx   r15: 0x%08lx\n",
276                 fp->regs[8], fp->regs[9], fp->lr);
277         pr_info("r16:0x%08lx   r17: 0x%08lx   r18: 0x%08lx    r19: 0x%08lx\n",
278                 fp->exregs[0], fp->exregs[1], fp->exregs[2], fp->exregs[3]);
279         pr_info("r20 0x%08lx   r21: 0x%08lx   r22: 0x%08lx    r23: 0x%08lx\n",
280                 fp->exregs[4], fp->exregs[5], fp->exregs[6], fp->exregs[7]);
281         pr_info("r24 0x%08lx   r25: 0x%08lx   r26: 0x%08lx    r27: 0x%08lx\n",
282                 fp->exregs[8], fp->exregs[9], fp->exregs[10], fp->exregs[11]);
283         pr_info("r28 0x%08lx   r29: 0x%08lx   r30: 0x%08lx    tls: 0x%08lx\n",
284                 fp->exregs[12], fp->exregs[13], fp->exregs[14], fp->tls);
285         pr_info("hi 0x%08lx    lo: 0x%08lx\n",
286                 fp->rhi, fp->rlo);
287 #else
288         pr_info("r6: 0x%08lx   r7: 0x%08lx   r8: 0x%08lx   r9: 0x%08lx\n",
289                 fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
290         pr_info("r10: 0x%08lx   r11: 0x%08lx   r12: 0x%08lx   r13: 0x%08lx\n",
291                 fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
292         pr_info("r14 0x%08lx   r1: 0x%08lx   r15: 0x%08lx\n",
293                 fp->regs[8], fp->regs[9], fp->lr);
294 #endif
295
296         pr_info("\nCODE:");
297         tp = ((unsigned char *) fp->pc) - 0x20;
298         tp += ((int)tp % 4) ? 2 : 0;
299         for (sp = (unsigned long *) tp, i = 0; (i < 0x40);  i += 4) {
300                 if ((i % 0x10) == 0)
301                         pr_cont("\n%08x: ", (int) (tp + i));
302                 pr_cont("%08x ", (int) *sp++);
303         }
304         pr_cont("\n");
305
306         pr_info("\nKERNEL STACK:");
307         tp = ((unsigned char *) fp) - 0x40;
308         for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {
309                 if ((i % 0x10) == 0)
310                         pr_cont("\n%08x: ", (int) (tp + i));
311                 pr_cont("%08x ", (int) *sp++);
312         }
313         pr_cont("\n");
314 }