xref: /openbmc/linux/arch/csky/kernel/ptrace.c (revision b830f94f)
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/pgtable.h>
22 #include <asm/processor.h>
23 #include <asm/asm-offsets.h>
24 
25 #include <abi/regdef.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  */
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 
46 static void singlestep_enable(struct task_struct *tsk)
47 {
48 	struct pt_regs *regs;
49 
50 	regs = task_pt_regs(tsk);
51 	regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_SI;
52 }
53 
54 /*
55  * Make sure the single step bit is set.
56  */
57 void user_enable_single_step(struct task_struct *child)
58 {
59 	singlestep_enable(child);
60 }
61 
62 void user_disable_single_step(struct task_struct *child)
63 {
64 	singlestep_disable(child);
65 }
66 
67 enum csky_regset {
68 	REGSET_GPR,
69 	REGSET_FPR,
70 };
71 
72 static int gpr_get(struct task_struct *target,
73 		   const struct user_regset *regset,
74 		   unsigned int pos, unsigned int count,
75 		   void *kbuf, void __user *ubuf)
76 {
77 	struct pt_regs *regs;
78 
79 	regs = task_pt_regs(target);
80 
81 	/* Abiv1 regs->tls is fake and we need sync here. */
82 	regs->tls = task_thread_info(target)->tp_value;
83 
84 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
85 }
86 
87 static int gpr_set(struct task_struct *target,
88 		    const struct user_regset *regset,
89 		    unsigned int pos, unsigned int count,
90 		    const void *kbuf, const void __user *ubuf)
91 {
92 	int ret;
93 	struct pt_regs regs;
94 
95 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &regs, 0, -1);
96 	if (ret)
97 		return ret;
98 
99 	regs.sr = task_pt_regs(target)->sr;
100 #ifdef CONFIG_CPU_HAS_HILO
101 	regs.dcsr = task_pt_regs(target)->dcsr;
102 #endif
103 	task_thread_info(target)->tp_value = regs.tls;
104 
105 	*task_pt_regs(target) = regs;
106 
107 	return 0;
108 }
109 
110 static int fpr_get(struct task_struct *target,
111 		   const struct user_regset *regset,
112 		   unsigned int pos, unsigned int count,
113 		   void *kbuf, void __user *ubuf)
114 {
115 	struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
116 
117 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
118 	int i;
119 	struct user_fp tmp = *regs;
120 
121 	for (i = 0; i < 16; i++) {
122 		tmp.vr[i*4] = regs->vr[i*2];
123 		tmp.vr[i*4 + 1] = regs->vr[i*2 + 1];
124 	}
125 
126 	for (i = 0; i < 32; i++)
127 		tmp.vr[64 + i] = regs->vr[32 + i];
128 
129 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);
130 #else
131 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
132 #endif
133 }
134 
135 static int fpr_set(struct task_struct *target,
136 		   const struct user_regset *regset,
137 		   unsigned int pos, unsigned int count,
138 		   const void *kbuf, const void __user *ubuf)
139 {
140 	int ret;
141 	struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
142 
143 #if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
144 	int i;
145 	struct user_fp tmp;
146 
147 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);
148 
149 	*regs = tmp;
150 
151 	for (i = 0; i < 16; i++) {
152 		regs->vr[i*2] = tmp.vr[i*4];
153 		regs->vr[i*2 + 1] = tmp.vr[i*4 + 1];
154 	}
155 
156 	for (i = 0; i < 32; i++)
157 		regs->vr[32 + i] = tmp.vr[64 + i];
158 #else
159 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
160 #endif
161 
162 	return ret;
163 }
164 
165 static const struct user_regset csky_regsets[] = {
166 	[REGSET_GPR] = {
167 		.core_note_type = NT_PRSTATUS,
168 		.n = sizeof(struct pt_regs) / sizeof(u32),
169 		.size = sizeof(u32),
170 		.align = sizeof(u32),
171 		.get = &gpr_get,
172 		.set = &gpr_set,
173 	},
174 	[REGSET_FPR] = {
175 		.core_note_type = NT_PRFPREG,
176 		.n = sizeof(struct user_fp) / sizeof(u32),
177 		.size = sizeof(u32),
178 		.align = sizeof(u32),
179 		.get = &fpr_get,
180 		.set = &fpr_set,
181 	},
182 };
183 
184 static const struct user_regset_view user_csky_view = {
185 	.name = "csky",
186 	.e_machine = ELF_ARCH,
187 	.regsets = csky_regsets,
188 	.n = ARRAY_SIZE(csky_regsets),
189 };
190 
191 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
192 {
193 	return &user_csky_view;
194 }
195 
196 void ptrace_disable(struct task_struct *child)
197 {
198 	singlestep_disable(child);
199 }
200 
201 long arch_ptrace(struct task_struct *child, long request,
202 		 unsigned long addr, unsigned long data)
203 {
204 	long ret = -EIO;
205 
206 	switch (request) {
207 	default:
208 		ret = ptrace_request(child, request, addr, data);
209 		break;
210 	}
211 
212 	return ret;
213 }
214 
215 asmlinkage void syscall_trace_enter(struct pt_regs *regs)
216 {
217 	if (test_thread_flag(TIF_SYSCALL_TRACE))
218 		if (tracehook_report_syscall_entry(regs))
219 			syscall_set_nr(current, regs, -1);
220 
221 	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
222 		trace_sys_enter(regs, syscall_get_nr(current, regs));
223 
224 	audit_syscall_entry(regs_syscallid(regs), regs->a0, regs->a1, regs->a2, regs->a3);
225 }
226 
227 asmlinkage void syscall_trace_exit(struct pt_regs *regs)
228 {
229 	audit_syscall_exit(regs);
230 
231 	if (test_thread_flag(TIF_SYSCALL_TRACE))
232 		tracehook_report_syscall_exit(regs, 0);
233 
234 	if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
235 		trace_sys_exit(regs, syscall_get_return_value(current, regs));
236 }
237 
238 extern void show_stack(struct task_struct *task, unsigned long *stack);
239 void show_regs(struct pt_regs *fp)
240 {
241 	unsigned long   *sp;
242 	unsigned char   *tp;
243 	int	i;
244 
245 	pr_info("\nCURRENT PROCESS:\n\n");
246 	pr_info("COMM=%s PID=%d\n", current->comm, current->pid);
247 
248 	if (current->mm) {
249 		pr_info("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
250 		       (int) current->mm->start_code,
251 		       (int) current->mm->end_code,
252 		       (int) current->mm->start_data,
253 		       (int) current->mm->end_data,
254 		       (int) current->mm->end_data,
255 		       (int) current->mm->brk);
256 		pr_info("USER-STACK=%08x  KERNEL-STACK=%08x\n\n",
257 		       (int) current->mm->start_stack,
258 		       (int) (((unsigned long) current) + 2 * PAGE_SIZE));
259 	}
260 
261 	pr_info("PC: 0x%08lx (%pS)\n", (long)fp->pc, (void *)fp->pc);
262 	pr_info("LR: 0x%08lx (%pS)\n", (long)fp->lr, (void *)fp->lr);
263 	pr_info("SP: 0x%08lx\n", (long)fp);
264 	pr_info("orig_a0: 0x%08lx\n", fp->orig_a0);
265 	pr_info("PSR: 0x%08lx\n", (long)fp->sr);
266 
267 	pr_info(" a0: 0x%08lx   a1: 0x%08lx   a2: 0x%08lx   a3: 0x%08lx\n",
268 		fp->a0, fp->a1, fp->a2, fp->a3);
269 #if defined(__CSKYABIV2__)
270 	pr_info(" r4: 0x%08lx   r5: 0x%08lx   r6: 0x%08lx   r7: 0x%08lx\n",
271 		fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
272 	pr_info(" r8: 0x%08lx   r9: 0x%08lx  r10: 0x%08lx  r11: 0x%08lx\n",
273 		fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
274 	pr_info("r12: 0x%08lx  r13: 0x%08lx  r15: 0x%08lx\n",
275 		fp->regs[8], fp->regs[9], fp->lr);
276 	pr_info("r16: 0x%08lx  r17: 0x%08lx  r18: 0x%08lx  r19: 0x%08lx\n",
277 		fp->exregs[0], fp->exregs[1], fp->exregs[2], fp->exregs[3]);
278 	pr_info("r20: 0x%08lx  r21: 0x%08lx  r22: 0x%08lx  r23: 0x%08lx\n",
279 		fp->exregs[4], fp->exregs[5], fp->exregs[6], fp->exregs[7]);
280 	pr_info("r24: 0x%08lx  r25: 0x%08lx  r26: 0x%08lx  r27: 0x%08lx\n",
281 		fp->exregs[8], fp->exregs[9], fp->exregs[10], fp->exregs[11]);
282 	pr_info("r28: 0x%08lx  r29: 0x%08lx  r30: 0x%08lx  tls: 0x%08lx\n",
283 		fp->exregs[12], fp->exregs[13], fp->exregs[14], fp->tls);
284 	pr_info(" hi: 0x%08lx   lo: 0x%08lx\n",
285 		fp->rhi, fp->rlo);
286 #else
287 	pr_info(" r6: 0x%08lx   r7: 0x%08lx   r8: 0x%08lx   r9: 0x%08lx\n",
288 		fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
289 	pr_info("r10: 0x%08lx  r11: 0x%08lx  r12: 0x%08lx  r13: 0x%08lx\n",
290 		fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
291 	pr_info("r14: 0x%08lx   r1: 0x%08lx  r15: 0x%08lx\n",
292 		fp->regs[8], fp->regs[9], fp->lr);
293 #endif
294 
295 	pr_info("\nCODE:");
296 	tp = ((unsigned char *) fp->pc) - 0x20;
297 	tp += ((int)tp % 4) ? 2 : 0;
298 	for (sp = (unsigned long *) tp, i = 0; (i < 0x40);  i += 4) {
299 		if ((i % 0x10) == 0)
300 			pr_cont("\n%08x: ", (int) (tp + i));
301 		pr_cont("%08x ", (int) *sp++);
302 	}
303 	pr_cont("\n");
304 
305 	pr_info("\nKERNEL STACK:");
306 	tp = ((unsigned char *) fp) - 0x40;
307 	for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {
308 		if ((i % 0x10) == 0)
309 			pr_cont("\n%08x: ", (int) (tp + i));
310 		pr_cont("%08x ", (int) *sp++);
311 	}
312 	pr_cont("\n");
313 
314 	show_stack(NULL, (unsigned long *)fp->regs[4]);
315 	return;
316 }
317