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/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         /* BIT(0) of regs.sr is Condition Code/Carry bit */
 100         regs.sr = (regs.sr & BIT(0)) | (task_pt_regs(target)->sr & ~BIT(0));
 101 #ifdef CONFIG_CPU_HAS_HILO
 102         regs.dcsr = task_pt_regs(target)->dcsr;
 103 #endif
 104         task_thread_info(target)->tp_value = regs.tls;
 105
 106         *task_pt_regs(target) = regs;
 107
 108         return 0;
 109 }
 110
 111 static int fpr_get(struct task_struct *target,
 112                    const struct user_regset *regset,
 113                    unsigned int pos, unsigned int count,
 114                    void *kbuf, void __user *ubuf)
 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 user_regset_copyout(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);
 131 #else
 132         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
 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                 .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                 .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 void ptrace_disable(struct task_struct *child)
 198 {
 199         singlestep_disable(child);
 200 }
 201
 202 long arch_ptrace(struct task_struct *child, long request,
 203                  unsigned long addr, unsigned long data)
 204 {
 205         long ret = -EIO;
 206
 207         switch (request) {
 208         default:
 209                 ret = ptrace_request(child, request, addr, data);
 210                 break;
 211         }
 212
 213         return ret;
 214 }
 215
 216 asmlinkage void syscall_trace_enter(struct pt_regs *regs)
 217 {
 218         if (test_thread_flag(TIF_SYSCALL_TRACE))
 219                 if (tracehook_report_syscall_entry(regs))
 220                         syscall_set_nr(current, regs, -1);
 221
 222         if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
 223                 trace_sys_enter(regs, syscall_get_nr(current, regs));
 224
 225         audit_syscall_entry(regs_syscallid(regs), regs->a0, regs->a1, regs->a2, regs->a3);
 226 }
 227
 228 asmlinkage void syscall_trace_exit(struct pt_regs *regs)
 229 {
 230         audit_syscall_exit(regs);
 231
 232         if (test_thread_flag(TIF_SYSCALL_TRACE))
 233                 tracehook_report_syscall_exit(regs, 0);
 234
 235         if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
 236                 trace_sys_exit(regs, syscall_get_return_value(current, regs));
 237 }
 238
 239 extern void show_stack(struct task_struct *task, unsigned long *stack);
 240 void show_regs(struct pt_regs *fp)
 241 {
 242         unsigned long   *sp;
 243         unsigned char   *tp;
 244         int     i;
 245
 246         pr_info("\nCURRENT PROCESS:\n\n");
 247         pr_info("COMM=%s PID=%d\n", current->comm, current->pid);
 248
 249         if (current->mm) {
 250                 pr_info("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
 251                        (int) current->mm->start_code,
 252                        (int) current->mm->end_code,
 253                        (int) current->mm->start_data,
 254                        (int) current->mm->end_data,
 255                        (int) current->mm->end_data,
 256                        (int) current->mm->brk);
 257                 pr_info("USER-STACK=%08x  KERNEL-STACK=%08x\n\n",
 258                        (int) current->mm->start_stack,
 259                        (int) (((unsigned long) current) + 2 * PAGE_SIZE));
 260         }
 261
 262         pr_info("PC: 0x%08lx (%pS)\n", (long)fp->pc, (void *)fp->pc);
 263         pr_info("LR: 0x%08lx (%pS)\n", (long)fp->lr, (void *)fp->lr);
 264         pr_info("SP: 0x%08lx\n", (long)fp);
 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
 315         show_stack(NULL, (unsigned long *)fp->regs[4]);
 316         return;
 317 }