/* * ptrace cpu depend helper functions * * Copyright 2003, 2015 Yoshinori Sato <ysato@users.sourceforge.jp> * * This file is subject to the terms and conditions of the GNU General * Public License. See the file COPYING in the main directory of * this archive for more details. */ #include <linux/linkage.h> #include <linux/sched/signal.h> #include <asm/ptrace.h> #define BREAKINST 0x5730 /* trapa #3 */ /* disable singlestep */ void user_disable_single_step(struct task_struct *child) { if ((long)child->thread.breakinfo.addr != -1L) { *(child->thread.breakinfo.addr) = child->thread.breakinfo.inst; child->thread.breakinfo.addr = (unsigned short *)-1L; } } /* calculate next pc */ enum jump_type {none, /* normal instruction */ jabs, /* absolute address jump */ ind, /* indirect address jump */ ret, /* return to subrutine */ reg, /* register indexed jump */ relb, /* pc relative jump (byte offset) */ relw, /* pc relative jump (word offset) */ }; /* opcode decode table define ptn: opcode pattern msk: opcode bitmask len: instruction length (<0 next table index) jmp: jump operation mode */ struct optable { unsigned char bitpattern; unsigned char bitmask; signed char length; signed char type; } __packed __aligned(1); #define OPTABLE(ptn, msk, len, jmp) \ { \ .bitpattern = ptn, \ .bitmask = msk, \ .length = len, \ .type = jmp, \ } static const struct optable optable_0[] = { OPTABLE(0x00, 0xff, 1, none), /* 0x00 */ OPTABLE(0x01, 0xff, -1, none), /* 0x01 */ OPTABLE(0x02, 0xfe, 1, none), /* 0x02-0x03 */ OPTABLE(0x04, 0xee, 1, none), /* 0x04-0x05/0x14-0x15 */ OPTABLE(0x06, 0xfe, 1, none), /* 0x06-0x07 */ OPTABLE(0x08, 0xea, 1, none), /* 0x08-0x09/0x0c-0x0d/0x18-0x19/0x1c-0x1d */ OPTABLE(0x0a, 0xee, 1, none), /* 0x0a-0x0b/0x1a-0x1b */ OPTABLE(0x0e, 0xee, 1, none), /* 0x0e-0x0f/0x1e-0x1f */ OPTABLE(0x10, 0xfc, 1, none), /* 0x10-0x13 */ OPTABLE(0x16, 0xfe, 1, none), /* 0x16-0x17 */ OPTABLE(0x20, 0xe0, 1, none), /* 0x20-0x3f */ OPTABLE(0x40, 0xf0, 1, relb), /* 0x40-0x4f */ OPTABLE(0x50, 0xfc, 1, none), /* 0x50-0x53 */ OPTABLE(0x54, 0xfd, 1, ret), /* 0x54/0x56 */ OPTABLE(0x55, 0xff, 1, relb), /* 0x55 */ OPTABLE(0x57, 0xff, 1, none), /* 0x57 */ OPTABLE(0x58, 0xfb, 2, relw), /* 0x58/0x5c */ OPTABLE(0x59, 0xfb, 1, reg), /* 0x59/0x5b */ OPTABLE(0x5a, 0xfb, 2, jabs), /* 0x5a/0x5e */ OPTABLE(0x5b, 0xfb, 2, ind), /* 0x5b/0x5f */ OPTABLE(0x60, 0xe8, 1, none), /* 0x60-0x67/0x70-0x77 */ OPTABLE(0x68, 0xfa, 1, none), /* 0x68-0x69/0x6c-0x6d */ OPTABLE(0x6a, 0xfe, -2, none), /* 0x6a-0x6b */ OPTABLE(0x6e, 0xfe, 2, none), /* 0x6e-0x6f */ OPTABLE(0x78, 0xff, 4, none), /* 0x78 */ OPTABLE(0x79, 0xff, 2, none), /* 0x79 */ OPTABLE(0x7a, 0xff, 3, none), /* 0x7a */ OPTABLE(0x7b, 0xff, 2, none), /* 0x7b */ OPTABLE(0x7c, 0xfc, 2, none), /* 0x7c-0x7f */ OPTABLE(0x80, 0x80, 1, none), /* 0x80-0xff */ }; static const struct optable optable_1[] = { OPTABLE(0x00, 0xff, -3, none), /* 0x0100 */ OPTABLE(0x40, 0xf0, -3, none), /* 0x0140-0x14f */ OPTABLE(0x80, 0xf0, 1, none), /* 0x0180-0x018f */ OPTABLE(0xc0, 0xc0, 2, none), /* 0x01c0-0x01ff */ }; static const struct optable optable_2[] = { OPTABLE(0x00, 0x20, 2, none), /* 0x6a0?/0x6a8?/0x6b0?/0x6b8? */ OPTABLE(0x20, 0x20, 3, none), /* 0x6a2?/0x6aa?/0x6b2?/0x6ba? */ }; static const struct optable optable_3[] = { OPTABLE(0x69, 0xfb, 2, none), /* 0x010069/0x01006d/014069/0x01406d */ OPTABLE(0x6b, 0xff, -4, none), /* 0x01006b/0x01406b */ OPTABLE(0x6f, 0xff, 3, none), /* 0x01006f/0x01406f */ OPTABLE(0x78, 0xff, 5, none), /* 0x010078/0x014078 */ }; static const struct optable optable_4[] = { /* 0x0100690?/0x01006d0?/0140690?/0x01406d0?/ 0x0100698?/0x01006d8?/0140698?/0x01406d8? */ OPTABLE(0x00, 0x78, 3, none), /* 0x0100692?/0x01006d2?/0140692?/0x01406d2?/ 0x010069a?/0x01006da?/014069a?/0x01406da? */ OPTABLE(0x20, 0x78, 4, none), }; static const struct optables_list { const struct optable *ptr; int size; } optables[] = { #define OPTABLES(no) \ { \ .ptr = optable_##no, \ .size = sizeof(optable_##no) / sizeof(struct optable), \ } OPTABLES(0), OPTABLES(1), OPTABLES(2), OPTABLES(3), OPTABLES(4), }; const unsigned char condmask[] = { 0x00, 0x40, 0x01, 0x04, 0x02, 0x08, 0x10, 0x20 }; static int isbranch(struct task_struct *task, int reson) { unsigned char cond = h8300_get_reg(task, PT_CCR); /* encode complex conditions */ /* B4: N^V B5: Z|(N^V) B6: C|Z */ __asm__("bld #3,%w0\n\t" "bxor #1,%w0\n\t" "bst #4,%w0\n\t" "bor #2,%w0\n\t" "bst #5,%w0\n\t" "bld #2,%w0\n\t" "bor #0,%w0\n\t" "bst #6,%w0\n\t" : "=&r"(cond) : "0"(cond) : "cc"); cond &= condmask[reson >> 1]; if (!(reson & 1)) return cond == 0; else return cond != 0; } static unsigned short *decode(struct task_struct *child, const struct optable *op, char *fetch_p, unsigned short *pc, unsigned char inst) { unsigned long addr; unsigned long *sp; int regno; switch (op->type) { case none: return (unsigned short *)pc + op->length; case jabs: addr = *(unsigned long *)pc; return (unsigned short *)(addr & 0x00ffffff); case ind: addr = *pc & 0xff; return (unsigned short *)(*(unsigned long *)addr); case ret: sp = (unsigned long *)h8300_get_reg(child, PT_USP); /* user stack frames | er0 | temporary saved +--------+ | exp | exception stack frames +--------+ | ret pc | userspace return address */ return (unsigned short *)(*(sp+2) & 0x00ffffff); case reg: regno = (*pc >> 4) & 0x07; if (regno == 0) addr = h8300_get_reg(child, PT_ER0); else addr = h8300_get_reg(child, regno-1 + PT_ER1); return (unsigned short *)addr; case relb: if (inst == 0x55 || isbranch(child, inst & 0x0f)) pc = (unsigned short *)((unsigned long)pc + ((signed char)(*fetch_p))); return pc+1; /* skip myself */ case relw: if (inst == 0x5c || isbranch(child, (*fetch_p & 0xf0) >> 4)) pc = (unsigned short *)((unsigned long)pc + ((signed short)(*(pc+1)))); return pc+2; /* skip myself */ default: return NULL; } } static unsigned short *nextpc(struct task_struct *child, unsigned short *pc) { const struct optable *op; unsigned char *fetch_p; int op_len; unsigned char inst; op = optables[0].ptr; op_len = optables[0].size; fetch_p = (unsigned char *)pc; inst = *fetch_p++; do { if ((inst & op->bitmask) == op->bitpattern) { if (op->length < 0) { op = optables[-op->length].ptr; op_len = optables[-op->length].size + 1; inst = *fetch_p++; } else return decode(child, op, fetch_p, pc, inst); } else op++; } while (--op_len > 0); return NULL; } /* Set breakpoint(s) to simulate a single step from the current PC. */ void user_enable_single_step(struct task_struct *child) { unsigned short *next; next = nextpc(child, (unsigned short *)h8300_get_reg(child, PT_PC)); child->thread.breakinfo.addr = next; child->thread.breakinfo.inst = *next; *next = BREAKINST; } asmlinkage void trace_trap(unsigned long bp) { if ((unsigned long)current->thread.breakinfo.addr == bp) { user_disable_single_step(current); force_sig(SIGTRAP, current); } else force_sig(SIGILL, current); }