GNU Linux-libre 4.19.314-gnu1
[releases.git] / arch / arc / kernel / ptrace.c
1 /*
2  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8
9 #include <linux/ptrace.h>
10 #include <linux/tracehook.h>
11 #include <linux/sched/task_stack.h>
12 #include <linux/regset.h>
13 #include <linux/unistd.h>
14 #include <linux/elf.h>
15
16 static struct callee_regs *task_callee_regs(struct task_struct *tsk)
17 {
18         struct callee_regs *tmp = (struct callee_regs *)tsk->thread.callee_reg;
19         return tmp;
20 }
21
22 static int genregs_get(struct task_struct *target,
23                        const struct user_regset *regset,
24                        unsigned int pos, unsigned int count,
25                        void *kbuf, void __user *ubuf)
26 {
27         const struct pt_regs *ptregs = task_pt_regs(target);
28         const struct callee_regs *cregs = task_callee_regs(target);
29         int ret = 0;
30         unsigned int stop_pc_val;
31
32 #define REG_O_CHUNK(START, END, PTR)    \
33         if (!ret)       \
34                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
35                         offsetof(struct user_regs_struct, START), \
36                         offsetof(struct user_regs_struct, END));
37
38 #define REG_O_ONE(LOC, PTR)     \
39         if (!ret)               \
40                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
41                         offsetof(struct user_regs_struct, LOC), \
42                         offsetof(struct user_regs_struct, LOC) + 4);
43
44 #define REG_O_ZERO(LOC)         \
45         if (!ret)               \
46                 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, \
47                         offsetof(struct user_regs_struct, LOC), \
48                         offsetof(struct user_regs_struct, LOC) + 4);
49
50         REG_O_ZERO(pad);
51         REG_O_ONE(scratch.bta, &ptregs->bta);
52         REG_O_ONE(scratch.lp_start, &ptregs->lp_start);
53         REG_O_ONE(scratch.lp_end, &ptregs->lp_end);
54         REG_O_ONE(scratch.lp_count, &ptregs->lp_count);
55         REG_O_ONE(scratch.status32, &ptregs->status32);
56         REG_O_ONE(scratch.ret, &ptregs->ret);
57         REG_O_ONE(scratch.blink, &ptregs->blink);
58         REG_O_ONE(scratch.fp, &ptregs->fp);
59         REG_O_ONE(scratch.gp, &ptregs->r26);
60         REG_O_ONE(scratch.r12, &ptregs->r12);
61         REG_O_ONE(scratch.r11, &ptregs->r11);
62         REG_O_ONE(scratch.r10, &ptregs->r10);
63         REG_O_ONE(scratch.r9, &ptregs->r9);
64         REG_O_ONE(scratch.r8, &ptregs->r8);
65         REG_O_ONE(scratch.r7, &ptregs->r7);
66         REG_O_ONE(scratch.r6, &ptregs->r6);
67         REG_O_ONE(scratch.r5, &ptregs->r5);
68         REG_O_ONE(scratch.r4, &ptregs->r4);
69         REG_O_ONE(scratch.r3, &ptregs->r3);
70         REG_O_ONE(scratch.r2, &ptregs->r2);
71         REG_O_ONE(scratch.r1, &ptregs->r1);
72         REG_O_ONE(scratch.r0, &ptregs->r0);
73         REG_O_ONE(scratch.sp, &ptregs->sp);
74
75         REG_O_ZERO(pad2);
76
77         REG_O_ONE(callee.r25, &cregs->r25);
78         REG_O_ONE(callee.r24, &cregs->r24);
79         REG_O_ONE(callee.r23, &cregs->r23);
80         REG_O_ONE(callee.r22, &cregs->r22);
81         REG_O_ONE(callee.r21, &cregs->r21);
82         REG_O_ONE(callee.r20, &cregs->r20);
83         REG_O_ONE(callee.r19, &cregs->r19);
84         REG_O_ONE(callee.r18, &cregs->r18);
85         REG_O_ONE(callee.r17, &cregs->r17);
86         REG_O_ONE(callee.r16, &cregs->r16);
87         REG_O_ONE(callee.r15, &cregs->r15);
88         REG_O_ONE(callee.r14, &cregs->r14);
89         REG_O_ONE(callee.r13, &cregs->r13);
90
91         REG_O_ONE(efa, &target->thread.fault_address);
92
93         if (!ret) {
94                 if (in_brkpt_trap(ptregs)) {
95                         stop_pc_val = target->thread.fault_address;
96                         pr_debug("\t\tstop_pc (brk-pt)\n");
97                 } else {
98                         stop_pc_val = ptregs->ret;
99                         pr_debug("\t\tstop_pc (others)\n");
100                 }
101
102                 REG_O_ONE(stop_pc, &stop_pc_val);
103         }
104
105         return ret;
106 }
107
108 static int genregs_set(struct task_struct *target,
109                        const struct user_regset *regset,
110                        unsigned int pos, unsigned int count,
111                        const void *kbuf, const void __user *ubuf)
112 {
113         const struct pt_regs *ptregs = task_pt_regs(target);
114         const struct callee_regs *cregs = task_callee_regs(target);
115         int ret = 0;
116
117 #define REG_IN_CHUNK(FIRST, NEXT, PTR)  \
118         if (!ret)                       \
119                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
120                         (void *)(PTR), \
121                         offsetof(struct user_regs_struct, FIRST), \
122                         offsetof(struct user_regs_struct, NEXT));
123
124 #define REG_IN_ONE(LOC, PTR)            \
125         if (!ret)                       \
126                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
127                         (void *)(PTR), \
128                         offsetof(struct user_regs_struct, LOC), \
129                         offsetof(struct user_regs_struct, LOC) + 4);
130
131 #define REG_IGNORE_ONE(LOC)             \
132         if (!ret)                       \
133                 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
134                         offsetof(struct user_regs_struct, LOC), \
135                         offsetof(struct user_regs_struct, LOC) + 4);
136
137         REG_IGNORE_ONE(pad);
138
139         REG_IN_ONE(scratch.bta, &ptregs->bta);
140         REG_IN_ONE(scratch.lp_start, &ptregs->lp_start);
141         REG_IN_ONE(scratch.lp_end, &ptregs->lp_end);
142         REG_IN_ONE(scratch.lp_count, &ptregs->lp_count);
143
144         REG_IGNORE_ONE(scratch.status32);
145
146         REG_IN_ONE(scratch.ret, &ptregs->ret);
147         REG_IN_ONE(scratch.blink, &ptregs->blink);
148         REG_IN_ONE(scratch.fp, &ptregs->fp);
149         REG_IN_ONE(scratch.gp, &ptregs->r26);
150         REG_IN_ONE(scratch.r12, &ptregs->r12);
151         REG_IN_ONE(scratch.r11, &ptregs->r11);
152         REG_IN_ONE(scratch.r10, &ptregs->r10);
153         REG_IN_ONE(scratch.r9, &ptregs->r9);
154         REG_IN_ONE(scratch.r8, &ptregs->r8);
155         REG_IN_ONE(scratch.r7, &ptregs->r7);
156         REG_IN_ONE(scratch.r6, &ptregs->r6);
157         REG_IN_ONE(scratch.r5, &ptregs->r5);
158         REG_IN_ONE(scratch.r4, &ptregs->r4);
159         REG_IN_ONE(scratch.r3, &ptregs->r3);
160         REG_IN_ONE(scratch.r2, &ptregs->r2);
161         REG_IN_ONE(scratch.r1, &ptregs->r1);
162         REG_IN_ONE(scratch.r0, &ptregs->r0);
163         REG_IN_ONE(scratch.sp, &ptregs->sp);
164
165         REG_IGNORE_ONE(pad2);
166
167         REG_IN_ONE(callee.r25, &cregs->r25);
168         REG_IN_ONE(callee.r24, &cregs->r24);
169         REG_IN_ONE(callee.r23, &cregs->r23);
170         REG_IN_ONE(callee.r22, &cregs->r22);
171         REG_IN_ONE(callee.r21, &cregs->r21);
172         REG_IN_ONE(callee.r20, &cregs->r20);
173         REG_IN_ONE(callee.r19, &cregs->r19);
174         REG_IN_ONE(callee.r18, &cregs->r18);
175         REG_IN_ONE(callee.r17, &cregs->r17);
176         REG_IN_ONE(callee.r16, &cregs->r16);
177         REG_IN_ONE(callee.r15, &cregs->r15);
178         REG_IN_ONE(callee.r14, &cregs->r14);
179         REG_IN_ONE(callee.r13, &cregs->r13);
180
181         REG_IGNORE_ONE(efa);                    /* efa update invalid */
182         REG_IGNORE_ONE(stop_pc);                /* PC updated via @ret */
183
184         return ret;
185 }
186
187 #ifdef CONFIG_ISA_ARCV2
188 static int arcv2regs_get(struct task_struct *target,
189                        const struct user_regset *regset,
190                        unsigned int pos, unsigned int count,
191                        void *kbuf, void __user *ubuf)
192 {
193         const struct pt_regs *regs = task_pt_regs(target);
194         int ret, copy_sz;
195
196         if (IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS))
197                 copy_sz = sizeof(struct user_regs_arcv2);
198         else
199                 copy_sz = 4;    /* r30 only */
200
201         /*
202          * itemized copy not needed like above as layout of regs (r30,r58,r59)
203          * is exactly same in kernel (pt_regs) and userspace (user_regs_arcv2)
204          */
205         ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &regs->r30,
206                                   0, copy_sz);
207
208         return ret;
209 }
210
211 static int arcv2regs_set(struct task_struct *target,
212                        const struct user_regset *regset,
213                        unsigned int pos, unsigned int count,
214                        const void *kbuf, const void __user *ubuf)
215 {
216         const struct pt_regs *regs = task_pt_regs(target);
217         int ret, copy_sz;
218
219         if (IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS))
220                 copy_sz = sizeof(struct user_regs_arcv2);
221         else
222                 copy_sz = 4;    /* r30 only */
223
224         ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, (void *)&regs->r30,
225                                   0, copy_sz);
226
227         return ret;
228 }
229
230 #endif
231
232 enum arc_getset {
233         REGSET_CMN,
234         REGSET_ARCV2,
235 };
236
237 static const struct user_regset arc_regsets[] = {
238         [REGSET_CMN] = {
239                .core_note_type = NT_PRSTATUS,
240                .n = ELF_NGREG,
241                .size = sizeof(unsigned long),
242                .align = sizeof(unsigned long),
243                .get = genregs_get,
244                .set = genregs_set,
245         },
246 #ifdef CONFIG_ISA_ARCV2
247         [REGSET_ARCV2] = {
248                .core_note_type = NT_ARC_V2,
249                .n = ELF_ARCV2REG,
250                .size = sizeof(unsigned long),
251                .align = sizeof(unsigned long),
252                .get = arcv2regs_get,
253                .set = arcv2regs_set,
254         },
255 #endif
256 };
257
258 static const struct user_regset_view user_arc_view = {
259         .name           = UTS_MACHINE,
260         .e_machine      = EM_ARC_INUSE,
261         .regsets        = arc_regsets,
262         .n              = ARRAY_SIZE(arc_regsets)
263 };
264
265 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
266 {
267         return &user_arc_view;
268 }
269
270 void ptrace_disable(struct task_struct *child)
271 {
272 }
273
274 long arch_ptrace(struct task_struct *child, long request,
275                  unsigned long addr, unsigned long data)
276 {
277         int ret = -EIO;
278
279         pr_debug("REQ=%ld: ADDR =0x%lx, DATA=0x%lx)\n", request, addr, data);
280
281         switch (request) {
282         case PTRACE_GET_THREAD_AREA:
283                 ret = put_user(task_thread_info(child)->thr_ptr,
284                                (unsigned long __user *)data);
285                 break;
286         default:
287                 ret = ptrace_request(child, request, addr, data);
288                 break;
289         }
290
291         return ret;
292 }
293
294 asmlinkage int syscall_trace_entry(struct pt_regs *regs)
295 {
296         if (tracehook_report_syscall_entry(regs))
297                 return ULONG_MAX;
298
299         return regs->r8;
300 }
301
302 asmlinkage void syscall_trace_exit(struct pt_regs *regs)
303 {
304         tracehook_report_syscall_exit(regs, 0);
305 }