LXR linux/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#include <abi/ckmmu.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 */
  38static 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        /* Enable irq */
  46        regs->sr |= BIT(6);
  47}
  48
  49static void singlestep_enable(struct task_struct *tsk)
  50{
  51        struct pt_regs *regs;
  52
  53        regs = task_pt_regs(tsk);
  54        regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_SI;
  55
  56        /* Disable irq */
  57        regs->sr &= ~BIT(6);
  58}
  59
  60/*
  61 * Make sure the single step bit is set.
  62 */
  63void user_enable_single_step(struct task_struct *child)
  64{
  65        singlestep_enable(child);
  66}
  67
  68void user_disable_single_step(struct task_struct *child)
  69{
  70        singlestep_disable(child);
  71}
  72
  73enum csky_regset {
  74        REGSET_GPR,
  75        REGSET_FPR,
  76};
  77
  78static int gpr_get(struct task_struct *target,
  79                   const struct user_regset *regset,
  80                   struct membuf to)
  81{
  82        struct pt_regs *regs = task_pt_regs(target);
  83
  84        /* Abiv1 regs->tls is fake and we need sync here. */
  85        regs->tls = task_thread_info(target)->tp_value;
  86
  87        return membuf_write(&to, regs, sizeof(*regs));
  88}
  89
  90static int gpr_set(struct task_struct *target,
  91                    const struct user_regset *regset,
  92                    unsigned int pos, unsigned int count,
  93                    const void *kbuf, const void __user *ubuf)
  94{
  95        int ret;
  96        struct pt_regs regs;
  97
  98        ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &regs, 0, -1);
  99        if (ret)
 100                return ret;
 101
 102        /* BIT(0) of regs.sr is Condition Code/Carry bit */
 103        regs.sr = (regs.sr & BIT(0)) | (task_pt_regs(target)->sr & ~BIT(0));
 104#ifdef CONFIG_CPU_HAS_HILO
 105        regs.dcsr = task_pt_regs(target)->dcsr;
 106#endif
 107        task_thread_info(target)->tp_value = regs.tls;
 108
 109        *task_pt_regs(target) = regs;
 110
 111        return 0;
 112}
 113
 114static int fpr_get(struct task_struct *target,
 115                   const struct user_regset *regset,
 116                   struct membuf to)
 117{
 118        struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
 119
 120#if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
 121        int i;
 122        struct user_fp tmp = *regs;
 123
 124        for (i = 0; i < 16; i++) {
 125                tmp.vr[i*4] = regs->vr[i*2];
 126                tmp.vr[i*4 + 1] = regs->vr[i*2 + 1];
 127        }
 128
 129        for (i = 0; i < 32; i++)
 130                tmp.vr[64 + i] = regs->vr[32 + i];
 131
 132        return membuf_write(&to, &tmp, sizeof(tmp));
 133#else
 134        return membuf_write(&to, regs, sizeof(*regs));
 135#endif
 136}
 137
 138static int fpr_set(struct task_struct *target,
 139                   const struct user_regset *regset,
 140                   unsigned int pos, unsigned int count,
 141                   const void *kbuf, const void __user *ubuf)
 142{
 143        int ret;
 144        struct user_fp *regs = (struct user_fp *)&target->thread.user_fp;
 145
 146#if defined(CONFIG_CPU_HAS_FPUV2) && !defined(CONFIG_CPU_HAS_VDSP)
 147        int i;
 148        struct user_fp tmp;
 149
 150        ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tmp, 0, -1);
 151
 152        *regs = tmp;
 153
 154        for (i = 0; i < 16; i++) {
 155                regs->vr[i*2] = tmp.vr[i*4];
 156                regs->vr[i*2 + 1] = tmp.vr[i*4 + 1];
 157        }
 158
 159        for (i = 0; i < 32; i++)
 160                regs->vr[32 + i] = tmp.vr[64 + i];
 161#else
 162        ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
 163#endif
 164
 165        return ret;
 166}
 167
 168static const struct user_regset csky_regsets[] = {
 169        [REGSET_GPR] = {
 170                .core_note_type = NT_PRSTATUS,
 171                .n = sizeof(struct pt_regs) / sizeof(u32),
 172                .size = sizeof(u32),
 173                .align = sizeof(u32),
 174                .regset_get = gpr_get,
 175                .set = gpr_set,
 176        },
 177        [REGSET_FPR] = {
 178                .core_note_type = NT_PRFPREG,
 179                .n = sizeof(struct user_fp) / sizeof(u32),
 180                .size = sizeof(u32),
 181                .align = sizeof(u32),
 182                .regset_get = fpr_get,
 183                .set = fpr_set,
 184        },
 185};
 186
 187static const struct user_regset_view user_csky_view = {
 188        .name = "csky",
 189        .e_machine = ELF_ARCH,
 190        .regsets = csky_regsets,
 191        .n = ARRAY_SIZE(csky_regsets),
 192};
 193
 194const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 195{
 196        return &user_csky_view;
 197}
 198
 199struct pt_regs_offset {
 200        const char *name;
 201        int offset;
 202};
 203
 204#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
 205#define REG_OFFSET_END {.name = NULL, .offset = 0}
 206
 207static const struct pt_regs_offset regoffset_table[] = {
 208        REG_OFFSET_NAME(tls),
 209        REG_OFFSET_NAME(lr),
 210        REG_OFFSET_NAME(pc),
 211        REG_OFFSET_NAME(sr),
 212        REG_OFFSET_NAME(usp),
 213        REG_OFFSET_NAME(orig_a0),
 214        REG_OFFSET_NAME(a0),
 215        REG_OFFSET_NAME(a1),
 216        REG_OFFSET_NAME(a2),
 217        REG_OFFSET_NAME(a3),
 218        REG_OFFSET_NAME(regs[0]),
 219        REG_OFFSET_NAME(regs[1]),
 220        REG_OFFSET_NAME(regs[2]),
 221        REG_OFFSET_NAME(regs[3]),
 222        REG_OFFSET_NAME(regs[4]),
 223        REG_OFFSET_NAME(regs[5]),
 224        REG_OFFSET_NAME(regs[6]),
 225        REG_OFFSET_NAME(regs[7]),
 226        REG_OFFSET_NAME(regs[8]),
 227        REG_OFFSET_NAME(regs[9]),
 228#if defined(__CSKYABIV2__)
 229        REG_OFFSET_NAME(exregs[0]),
 230        REG_OFFSET_NAME(exregs[1]),
 231        REG_OFFSET_NAME(exregs[2]),
 232        REG_OFFSET_NAME(exregs[3]),
 233        REG_OFFSET_NAME(exregs[4]),
 234        REG_OFFSET_NAME(exregs[5]),
 235        REG_OFFSET_NAME(exregs[6]),
 236        REG_OFFSET_NAME(exregs[7]),
 237        REG_OFFSET_NAME(exregs[8]),
 238        REG_OFFSET_NAME(exregs[9]),
 239        REG_OFFSET_NAME(exregs[10]),
 240        REG_OFFSET_NAME(exregs[11]),
 241        REG_OFFSET_NAME(exregs[12]),
 242        REG_OFFSET_NAME(exregs[13]),
 243        REG_OFFSET_NAME(exregs[14]),
 244        REG_OFFSET_NAME(rhi),
 245        REG_OFFSET_NAME(rlo),
 246        REG_OFFSET_NAME(dcsr),
 247#endif
 248        REG_OFFSET_END,
 249};
 250
 251/**
 252 * regs_query_register_offset() - query register offset from its name
 253 * @name:       the name of a register
 254 *
 255 * regs_query_register_offset() returns the offset of a register in struct
 256 * pt_regs from its name. If the name is invalid, this returns -EINVAL;
 257 */
 258int regs_query_register_offset(const char *name)
 259{
 260        const struct pt_regs_offset *roff;
 261
 262        for (roff = regoffset_table; roff->name != NULL; roff++)
 263                if (!strcmp(roff->name, name))
 264                        return roff->offset;
 265        return -EINVAL;
 266}
 267
 268/**
 269 * regs_within_kernel_stack() - check the address in the stack
 270 * @regs:      pt_regs which contains kernel stack pointer.
 271 * @addr:      address which is checked.
 272 *
 273 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
 274 * If @addr is within the kernel stack, it returns true. If not, returns false.
 275 */
 276static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
 277{
 278        return (addr & ~(THREAD_SIZE - 1))  ==
 279                (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1));
 280}
 281
 282/**
 283 * regs_get_kernel_stack_nth() - get Nth entry of the stack
 284 * @regs:       pt_regs which contains kernel stack pointer.
 285 * @n:          stack entry number.
 286 *
 287 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
 288 * is specified by @regs. If the @n th entry is NOT in the kernel stack,
 289 * this returns 0.
 290 */
 291unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
 292{
 293        unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
 294
 295        addr += n;
 296        if (regs_within_kernel_stack(regs, (unsigned long)addr))
 297                return *addr;
 298        else
 299                return 0;
 300}
 301
 302void ptrace_disable(struct task_struct *child)
 303{
 304        singlestep_disable(child);
 305}
 306
 307long arch_ptrace(struct task_struct *child, long request,
 308                 unsigned long addr, unsigned long data)
 309{
 310        long ret = -EIO;
 311
 312        switch (request) {
 313        default:
 314                ret = ptrace_request(child, request, addr, data);
 315                break;
 316        }
 317
 318        return ret;
 319}
 320
 321asmlinkage int syscall_trace_enter(struct pt_regs *regs)
 322{
 323        if (test_thread_flag(TIF_SYSCALL_TRACE))
 324                if (tracehook_report_syscall_entry(regs))
 325                        return -1;
 326
 327        if (secure_computing() == -1)
 328                return -1;
 329
 330        if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
 331                trace_sys_enter(regs, syscall_get_nr(current, regs));
 332
 333        audit_syscall_entry(regs_syscallid(regs), regs->a0, regs->a1, regs->a2, regs->a3);
 334        return 0;
 335}
 336
 337asmlinkage void syscall_trace_exit(struct pt_regs *regs)
 338{
 339        audit_syscall_exit(regs);
 340
 341        if (test_thread_flag(TIF_SYSCALL_TRACE))
 342                tracehook_report_syscall_exit(regs, 0);
 343
 344        if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
 345                trace_sys_exit(regs, syscall_get_return_value(current, regs));
 346}
 347
 348#ifdef CONFIG_CPU_CK860
 349static void show_iutlb(void)
 350{
 351        int entry, i;
 352        unsigned long flags;
 353        unsigned long oldpid;
 354        unsigned long entryhi[16], entrylo0[16], entrylo1[16];
 355
 356        oldpid = read_mmu_entryhi();
 357
 358        entry = 0x8000;
 359
 360        local_irq_save(flags);
 361
 362        for (i = 0; i < 16; i++) {
 363                write_mmu_index(entry);
 364                tlb_read();
 365                entryhi[i]  = read_mmu_entryhi();
 366                entrylo0[i] = read_mmu_entrylo0();
 367                entrylo1[i] = read_mmu_entrylo1();
 368
 369                entry++;
 370        }
 371
 372        local_irq_restore(flags);
 373
 374        write_mmu_entryhi(oldpid);
 375
 376        printk("\n\n\n");
 377        for (i = 0; i < 16; i++)
 378                printk("iutlb[%d]:      entryhi - 0x%lx;        entrylo0 - 0x%lx;"
 379                       "        entrylo1 - 0x%lx\n",
 380                         i, entryhi[i], entrylo0[i], entrylo1[i]);
 381        printk("\n\n\n");
 382}
 383
 384static void show_dutlb(void)
 385{
 386        int entry, i;
 387        unsigned long flags;
 388        unsigned long oldpid;
 389        unsigned long entryhi[16], entrylo0[16], entrylo1[16];
 390
 391        oldpid = read_mmu_entryhi();
 392
 393        entry = 0x4000;
 394
 395        local_irq_save(flags);
 396
 397        for (i = 0; i < 16; i++) {
 398                write_mmu_index(entry);
 399                tlb_read();
 400                entryhi[i]  = read_mmu_entryhi();
 401                entrylo0[i] = read_mmu_entrylo0();
 402                entrylo1[i] = read_mmu_entrylo1();
 403
 404                entry++;
 405        }
 406
 407        local_irq_restore(flags);
 408
 409        write_mmu_entryhi(oldpid);
 410
 411        printk("\n\n\n");
 412        for (i = 0; i < 16; i++)
 413                printk("dutlb[%d]:      entryhi - 0x%lx;        entrylo0 - 0x%lx;"
 414                       "        entrylo1 - 0x%lx\n",
 415                         i, entryhi[i], entrylo0[i], entrylo1[i]);
 416        printk("\n\n\n");
 417}
 418
 419static unsigned long entryhi[1024], entrylo0[1024], entrylo1[1024];
 420static void show_jtlb(void)
 421{
 422        int entry;
 423        unsigned long flags;
 424        unsigned long oldpid;
 425
 426        oldpid = read_mmu_entryhi();
 427
 428        entry = 0;
 429
 430        local_irq_save(flags);
 431        while (entry < 1024) {
 432                write_mmu_index(entry);
 433                tlb_read();
 434                entryhi[entry]  = read_mmu_entryhi();
 435                entrylo0[entry] = read_mmu_entrylo0();
 436                entrylo1[entry] = read_mmu_entrylo1();
 437
 438                entry++;
 439        }
 440        local_irq_restore(flags);
 441
 442        write_mmu_entryhi(oldpid);
 443
 444        printk("\n\n\n");
 445
 446        for (entry = 0; entry < 1024; entry++)
 447                printk("jtlb[%x]:       entryhi - 0x%lx;        entrylo0 - 0x%lx;"
 448                       "        entrylo1 - 0x%lx\n",
 449                         entry, entryhi[entry], entrylo0[entry], entrylo1[entry]);
 450        printk("\n\n\n");
 451}
 452
 453static void show_tlb(void)
 454{
 455        show_iutlb();
 456        show_dutlb();
 457        show_jtlb();
 458}
 459#else
 460static void show_tlb(void)
 461{
 462        return;
 463}
 464#endif
 465
 466void show_regs(struct pt_regs *fp)
 467{
 468        pr_info("\nCURRENT PROCESS:\n\n");
 469        pr_info("COMM=%s PID=%d\n", current->comm, current->pid);
 470
 471        if (current->mm) {
 472                pr_info("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
 473                       (int) current->mm->start_code,
 474                       (int) current->mm->end_code,
 475                       (int) current->mm->start_data,
 476                       (int) current->mm->end_data,
 477                       (int) current->mm->end_data,
 478                       (int) current->mm->brk);
 479                pr_info("USER-STACK=%08x  KERNEL-STACK=%08x\n\n",
 480                       (int) current->mm->start_stack,
 481                       (int) (((unsigned long) current) + 2 * PAGE_SIZE));
 482        }
 483
 484        pr_info("PC: 0x%08lx (%pS)\n", (long)fp->pc, (void *)fp->pc);
 485        pr_info("LR: 0x%08lx (%pS)\n", (long)fp->lr, (void *)fp->lr);
 486        pr_info("SP: 0x%08lx\n", (long)fp->usp);
 487        pr_info("PSR: 0x%08lx\n", (long)fp->sr);
 488        pr_info("orig_a0: 0x%08lx\n", fp->orig_a0);
 489        pr_info("PT_REGS: 0x%08lx\n", (long)fp);
 490
 491        pr_info(" a0: 0x%08lx   a1: 0x%08lx   a2: 0x%08lx   a3: 0x%08lx\n",
 492                fp->a0, fp->a1, fp->a2, fp->a3);
 493#if defined(__CSKYABIV2__)
 494        pr_info(" r4: 0x%08lx   r5: 0x%08lx   r6: 0x%08lx   r7: 0x%08lx\n",
 495                fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
 496        pr_info(" r8: 0x%08lx   r9: 0x%08lx  r10: 0x%08lx  r11: 0x%08lx\n",
 497                fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
 498        pr_info("r12: 0x%08lx  r13: 0x%08lx  r15: 0x%08lx\n",
 499                fp->regs[8], fp->regs[9], fp->lr);
 500        pr_info("r16: 0x%08lx  r17: 0x%08lx  r18: 0x%08lx  r19: 0x%08lx\n",
 501                fp->exregs[0], fp->exregs[1], fp->exregs[2], fp->exregs[3]);
 502        pr_info("r20: 0x%08lx  r21: 0x%08lx  r22: 0x%08lx  r23: 0x%08lx\n",
 503                fp->exregs[4], fp->exregs[5], fp->exregs[6], fp->exregs[7]);
 504        pr_info("r24: 0x%08lx  r25: 0x%08lx  r26: 0x%08lx  r27: 0x%08lx\n",
 505                fp->exregs[8], fp->exregs[9], fp->exregs[10], fp->exregs[11]);
 506        pr_info("r28: 0x%08lx  r29: 0x%08lx  r30: 0x%08lx  tls: 0x%08lx\n",
 507                fp->exregs[12], fp->exregs[13], fp->exregs[14], fp->tls);
 508        pr_info(" hi: 0x%08lx   lo: 0x%08lx\n",
 509                fp->rhi, fp->rlo);
 510#else
 511        pr_info(" r6: 0x%08lx   r7: 0x%08lx   r8: 0x%08lx   r9: 0x%08lx\n",
 512                fp->regs[0], fp->regs[1], fp->regs[2], fp->regs[3]);
 513        pr_info("r10: 0x%08lx  r11: 0x%08lx  r12: 0x%08lx  r13: 0x%08lx\n",
 514                fp->regs[4], fp->regs[5], fp->regs[6], fp->regs[7]);
 515        pr_info("r14: 0x%08lx   r1: 0x%08lx\n",
 516                fp->regs[8], fp->regs[9]);
 517#endif
 518
 519        show_tlb();
 520
 521        return;
 522}
 523