diff options
Diffstat (limited to 'arch/powerpc/lib/sstep.c')
-rw-r--r-- | arch/powerpc/lib/sstep.c | 2015 |
1 files changed, 2015 insertions, 0 deletions
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c new file mode 100644 index 000000000..dc885b30f --- /dev/null +++ b/arch/powerpc/lib/sstep.c @@ -0,0 +1,2015 @@ +/* + * Single-step support. + * + * Copyright (C) 2004 Paul Mackerras <paulus@au.ibm.com>, IBM + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ +#include <linux/kernel.h> +#include <linux/kprobes.h> +#include <linux/ptrace.h> +#include <linux/prefetch.h> +#include <asm/sstep.h> +#include <asm/processor.h> +#include <asm/uaccess.h> +#include <asm/cputable.h> + +extern char system_call_common[]; + +#ifdef CONFIG_PPC64 +/* Bits in SRR1 that are copied from MSR */ +#define MSR_MASK 0xffffffff87c0ffffUL +#else +#define MSR_MASK 0x87c0ffff +#endif + +/* Bits in XER */ +#define XER_SO 0x80000000U +#define XER_OV 0x40000000U +#define XER_CA 0x20000000U + +#ifdef CONFIG_PPC_FPU +/* + * Functions in ldstfp.S + */ +extern int do_lfs(int rn, unsigned long ea); +extern int do_lfd(int rn, unsigned long ea); +extern int do_stfs(int rn, unsigned long ea); +extern int do_stfd(int rn, unsigned long ea); +extern int do_lvx(int rn, unsigned long ea); +extern int do_stvx(int rn, unsigned long ea); +extern int do_lxvd2x(int rn, unsigned long ea); +extern int do_stxvd2x(int rn, unsigned long ea); +#endif + +/* + * Emulate the truncation of 64 bit values in 32-bit mode. + */ +static unsigned long truncate_if_32bit(unsigned long msr, unsigned long val) +{ +#ifdef __powerpc64__ + if ((msr & MSR_64BIT) == 0) + val &= 0xffffffffUL; +#endif + return val; +} + +/* + * Determine whether a conditional branch instruction would branch. + */ +static int __kprobes branch_taken(unsigned int instr, struct pt_regs *regs) +{ + unsigned int bo = (instr >> 21) & 0x1f; + unsigned int bi; + + if ((bo & 4) == 0) { + /* decrement counter */ + --regs->ctr; + if (((bo >> 1) & 1) ^ (regs->ctr == 0)) + return 0; + } + if ((bo & 0x10) == 0) { + /* check bit from CR */ + bi = (instr >> 16) & 0x1f; + if (((regs->ccr >> (31 - bi)) & 1) != ((bo >> 3) & 1)) + return 0; + } + return 1; +} + + +static long __kprobes address_ok(struct pt_regs *regs, unsigned long ea, int nb) +{ + if (!user_mode(regs)) + return 1; + return __access_ok(ea, nb, USER_DS); +} + +/* + * Calculate effective address for a D-form instruction + */ +static unsigned long __kprobes dform_ea(unsigned int instr, struct pt_regs *regs) +{ + int ra; + unsigned long ea; + + ra = (instr >> 16) & 0x1f; + ea = (signed short) instr; /* sign-extend */ + if (ra) + ea += regs->gpr[ra]; + + return truncate_if_32bit(regs->msr, ea); +} + +#ifdef __powerpc64__ +/* + * Calculate effective address for a DS-form instruction + */ +static unsigned long __kprobes dsform_ea(unsigned int instr, struct pt_regs *regs) +{ + int ra; + unsigned long ea; + + ra = (instr >> 16) & 0x1f; + ea = (signed short) (instr & ~3); /* sign-extend */ + if (ra) + ea += regs->gpr[ra]; + + return truncate_if_32bit(regs->msr, ea); +} +#endif /* __powerpc64 */ + +/* + * Calculate effective address for an X-form instruction + */ +static unsigned long __kprobes xform_ea(unsigned int instr, + struct pt_regs *regs) +{ + int ra, rb; + unsigned long ea; + + ra = (instr >> 16) & 0x1f; + rb = (instr >> 11) & 0x1f; + ea = regs->gpr[rb]; + if (ra) + ea += regs->gpr[ra]; + + return truncate_if_32bit(regs->msr, ea); +} + +/* + * Return the largest power of 2, not greater than sizeof(unsigned long), + * such that x is a multiple of it. + */ +static inline unsigned long max_align(unsigned long x) +{ + x |= sizeof(unsigned long); + return x & -x; /* isolates rightmost bit */ +} + + +static inline unsigned long byterev_2(unsigned long x) +{ + return ((x >> 8) & 0xff) | ((x & 0xff) << 8); +} + +static inline unsigned long byterev_4(unsigned long x) +{ + return ((x >> 24) & 0xff) | ((x >> 8) & 0xff00) | + ((x & 0xff00) << 8) | ((x & 0xff) << 24); +} + +#ifdef __powerpc64__ +static inline unsigned long byterev_8(unsigned long x) +{ + return (byterev_4(x) << 32) | byterev_4(x >> 32); +} +#endif + +static int __kprobes read_mem_aligned(unsigned long *dest, unsigned long ea, + int nb) +{ + int err = 0; + unsigned long x = 0; + + switch (nb) { + case 1: + err = __get_user(x, (unsigned char __user *) ea); + break; + case 2: + err = __get_user(x, (unsigned short __user *) ea); + break; + case 4: + err = __get_user(x, (unsigned int __user *) ea); + break; +#ifdef __powerpc64__ + case 8: + err = __get_user(x, (unsigned long __user *) ea); + break; +#endif + } + if (!err) + *dest = x; + return err; +} + +static int __kprobes read_mem_unaligned(unsigned long *dest, unsigned long ea, + int nb, struct pt_regs *regs) +{ + int err; + unsigned long x, b, c; +#ifdef __LITTLE_ENDIAN__ + int len = nb; /* save a copy of the length for byte reversal */ +#endif + + /* unaligned, do this in pieces */ + x = 0; + for (; nb > 0; nb -= c) { +#ifdef __LITTLE_ENDIAN__ + c = 1; +#endif +#ifdef __BIG_ENDIAN__ + c = max_align(ea); +#endif + if (c > nb) + c = max_align(nb); + err = read_mem_aligned(&b, ea, c); + if (err) + return err; + x = (x << (8 * c)) + b; + ea += c; + } +#ifdef __LITTLE_ENDIAN__ + switch (len) { + case 2: + *dest = byterev_2(x); + break; + case 4: + *dest = byterev_4(x); + break; +#ifdef __powerpc64__ + case 8: + *dest = byterev_8(x); + break; +#endif + } +#endif +#ifdef __BIG_ENDIAN__ + *dest = x; +#endif + return 0; +} + +/* + * Read memory at address ea for nb bytes, return 0 for success + * or -EFAULT if an error occurred. + */ +static int __kprobes read_mem(unsigned long *dest, unsigned long ea, int nb, + struct pt_regs *regs) +{ + if (!address_ok(regs, ea, nb)) + return -EFAULT; + if ((ea & (nb - 1)) == 0) + return read_mem_aligned(dest, ea, nb); + return read_mem_unaligned(dest, ea, nb, regs); +} + +static int __kprobes write_mem_aligned(unsigned long val, unsigned long ea, + int nb) +{ + int err = 0; + + switch (nb) { + case 1: + err = __put_user(val, (unsigned char __user *) ea); + break; + case 2: + err = __put_user(val, (unsigned short __user *) ea); + break; + case 4: + err = __put_user(val, (unsigned int __user *) ea); + break; +#ifdef __powerpc64__ + case 8: + err = __put_user(val, (unsigned long __user *) ea); + break; +#endif + } + return err; +} + +static int __kprobes write_mem_unaligned(unsigned long val, unsigned long ea, + int nb, struct pt_regs *regs) +{ + int err; + unsigned long c; + +#ifdef __LITTLE_ENDIAN__ + switch (nb) { + case 2: + val = byterev_2(val); + break; + case 4: + val = byterev_4(val); + break; +#ifdef __powerpc64__ + case 8: + val = byterev_8(val); + break; +#endif + } +#endif + /* unaligned or little-endian, do this in pieces */ + for (; nb > 0; nb -= c) { +#ifdef __LITTLE_ENDIAN__ + c = 1; +#endif +#ifdef __BIG_ENDIAN__ + c = max_align(ea); +#endif + if (c > nb) + c = max_align(nb); + err = write_mem_aligned(val >> (nb - c) * 8, ea, c); + if (err) + return err; + ea += c; + } + return 0; +} + +/* + * Write memory at address ea for nb bytes, return 0 for success + * or -EFAULT if an error occurred. + */ +static int __kprobes write_mem(unsigned long val, unsigned long ea, int nb, + struct pt_regs *regs) +{ + if (!address_ok(regs, ea, nb)) + return -EFAULT; + if ((ea & (nb - 1)) == 0) + return write_mem_aligned(val, ea, nb); + return write_mem_unaligned(val, ea, nb, regs); +} + +#ifdef CONFIG_PPC_FPU +/* + * Check the address and alignment, and call func to do the actual + * load or store. + */ +static int __kprobes do_fp_load(int rn, int (*func)(int, unsigned long), + unsigned long ea, int nb, + struct pt_regs *regs) +{ + int err; + union { + double dbl; + unsigned long ul[2]; + struct { +#ifdef __BIG_ENDIAN__ + unsigned _pad_; + unsigned word; +#endif +#ifdef __LITTLE_ENDIAN__ + unsigned word; + unsigned _pad_; +#endif + } single; + } data; + unsigned long ptr; + + if (!address_ok(regs, ea, nb)) + return -EFAULT; + if ((ea & 3) == 0) + return (*func)(rn, ea); + ptr = (unsigned long) &data.ul; + if (sizeof(unsigned long) == 8 || nb == 4) { + err = read_mem_unaligned(&data.ul[0], ea, nb, regs); + if (nb == 4) + ptr = (unsigned long)&(data.single.word); + } else { + /* reading a double on 32-bit */ + err = read_mem_unaligned(&data.ul[0], ea, 4, regs); + if (!err) + err = read_mem_unaligned(&data.ul[1], ea + 4, 4, regs); + } + if (err) + return err; + return (*func)(rn, ptr); +} + +static int __kprobes do_fp_store(int rn, int (*func)(int, unsigned long), + unsigned long ea, int nb, + struct pt_regs *regs) +{ + int err; + union { + double dbl; + unsigned long ul[2]; + struct { +#ifdef __BIG_ENDIAN__ + unsigned _pad_; + unsigned word; +#endif +#ifdef __LITTLE_ENDIAN__ + unsigned word; + unsigned _pad_; +#endif + } single; + } data; + unsigned long ptr; + + if (!address_ok(regs, ea, nb)) + return -EFAULT; + if ((ea & 3) == 0) + return (*func)(rn, ea); + ptr = (unsigned long) &data.ul[0]; + if (sizeof(unsigned long) == 8 || nb == 4) { + if (nb == 4) + ptr = (unsigned long)&(data.single.word); + err = (*func)(rn, ptr); + if (err) + return err; + err = write_mem_unaligned(data.ul[0], ea, nb, regs); + } else { + /* writing a double on 32-bit */ + err = (*func)(rn, ptr); + if (err) + return err; + err = write_mem_unaligned(data.ul[0], ea, 4, regs); + if (!err) + err = write_mem_unaligned(data.ul[1], ea + 4, 4, regs); + } + return err; +} +#endif + +#ifdef CONFIG_ALTIVEC +/* For Altivec/VMX, no need to worry about alignment */ +static int __kprobes do_vec_load(int rn, int (*func)(int, unsigned long), + unsigned long ea, struct pt_regs *regs) +{ + if (!address_ok(regs, ea & ~0xfUL, 16)) + return -EFAULT; + return (*func)(rn, ea); +} + +static int __kprobes do_vec_store(int rn, int (*func)(int, unsigned long), + unsigned long ea, struct pt_regs *regs) +{ + if (!address_ok(regs, ea & ~0xfUL, 16)) + return -EFAULT; + return (*func)(rn, ea); +} +#endif /* CONFIG_ALTIVEC */ + +#ifdef CONFIG_VSX +static int __kprobes do_vsx_load(int rn, int (*func)(int, unsigned long), + unsigned long ea, struct pt_regs *regs) +{ + int err; + unsigned long val[2]; + + if (!address_ok(regs, ea, 16)) + return -EFAULT; + if ((ea & 3) == 0) + return (*func)(rn, ea); + err = read_mem_unaligned(&val[0], ea, 8, regs); + if (!err) + err = read_mem_unaligned(&val[1], ea + 8, 8, regs); + if (!err) + err = (*func)(rn, (unsigned long) &val[0]); + return err; +} + +static int __kprobes do_vsx_store(int rn, int (*func)(int, unsigned long), + unsigned long ea, struct pt_regs *regs) +{ + int err; + unsigned long val[2]; + + if (!address_ok(regs, ea, 16)) + return -EFAULT; + if ((ea & 3) == 0) + return (*func)(rn, ea); + err = (*func)(rn, (unsigned long) &val[0]); + if (err) + return err; + err = write_mem_unaligned(val[0], ea, 8, regs); + if (!err) + err = write_mem_unaligned(val[1], ea + 8, 8, regs); + return err; +} +#endif /* CONFIG_VSX */ + +#define __put_user_asmx(x, addr, err, op, cr) \ + __asm__ __volatile__( \ + "1: " op " %2,0,%3\n" \ + " mfcr %1\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3: li %0,%4\n" \ + " b 2b\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + PPC_LONG_ALIGN "\n" \ + PPC_LONG "1b,3b\n" \ + ".previous" \ + : "=r" (err), "=r" (cr) \ + : "r" (x), "r" (addr), "i" (-EFAULT), "0" (err)) + +#define __get_user_asmx(x, addr, err, op) \ + __asm__ __volatile__( \ + "1: "op" %1,0,%2\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3: li %0,%3\n" \ + " b 2b\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + PPC_LONG_ALIGN "\n" \ + PPC_LONG "1b,3b\n" \ + ".previous" \ + : "=r" (err), "=r" (x) \ + : "r" (addr), "i" (-EFAULT), "0" (err)) + +#define __cacheop_user_asmx(addr, err, op) \ + __asm__ __volatile__( \ + "1: "op" 0,%1\n" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3: li %0,%3\n" \ + " b 2b\n" \ + ".previous\n" \ + ".section __ex_table,\"a\"\n" \ + PPC_LONG_ALIGN "\n" \ + PPC_LONG "1b,3b\n" \ + ".previous" \ + : "=r" (err) \ + : "r" (addr), "i" (-EFAULT), "0" (err)) + +static void __kprobes set_cr0(struct pt_regs *regs, int rd) +{ + long val = regs->gpr[rd]; + + regs->ccr = (regs->ccr & 0x0fffffff) | ((regs->xer >> 3) & 0x10000000); +#ifdef __powerpc64__ + if (!(regs->msr & MSR_64BIT)) + val = (int) val; +#endif + if (val < 0) + regs->ccr |= 0x80000000; + else if (val > 0) + regs->ccr |= 0x40000000; + else + regs->ccr |= 0x20000000; +} + +static void __kprobes add_with_carry(struct pt_regs *regs, int rd, + unsigned long val1, unsigned long val2, + unsigned long carry_in) +{ + unsigned long val = val1 + val2; + + if (carry_in) + ++val; + regs->gpr[rd] = val; +#ifdef __powerpc64__ + if (!(regs->msr & MSR_64BIT)) { + val = (unsigned int) val; + val1 = (unsigned int) val1; + } +#endif + if (val < val1 || (carry_in && val == val1)) + regs->xer |= XER_CA; + else + regs->xer &= ~XER_CA; +} + +static void __kprobes do_cmp_signed(struct pt_regs *regs, long v1, long v2, + int crfld) +{ + unsigned int crval, shift; + + crval = (regs->xer >> 31) & 1; /* get SO bit */ + if (v1 < v2) + crval |= 8; + else if (v1 > v2) + crval |= 4; + else + crval |= 2; + shift = (7 - crfld) * 4; + regs->ccr = (regs->ccr & ~(0xf << shift)) | (crval << shift); +} + +static void __kprobes do_cmp_unsigned(struct pt_regs *regs, unsigned long v1, + unsigned long v2, int crfld) +{ + unsigned int crval, shift; + + crval = (regs->xer >> 31) & 1; /* get SO bit */ + if (v1 < v2) + crval |= 8; + else if (v1 > v2) + crval |= 4; + else + crval |= 2; + shift = (7 - crfld) * 4; + regs->ccr = (regs->ccr & ~(0xf << shift)) | (crval << shift); +} + +static int __kprobes trap_compare(long v1, long v2) +{ + int ret = 0; + + if (v1 < v2) + ret |= 0x10; + else if (v1 > v2) + ret |= 0x08; + else + ret |= 0x04; + if ((unsigned long)v1 < (unsigned long)v2) + ret |= 0x02; + else if ((unsigned long)v1 > (unsigned long)v2) + ret |= 0x01; + return ret; +} + +/* + * Elements of 32-bit rotate and mask instructions. + */ +#define MASK32(mb, me) ((0xffffffffUL >> (mb)) + \ + ((signed long)-0x80000000L >> (me)) + ((me) >= (mb))) +#ifdef __powerpc64__ +#define MASK64_L(mb) (~0UL >> (mb)) +#define MASK64_R(me) ((signed long)-0x8000000000000000L >> (me)) +#define MASK64(mb, me) (MASK64_L(mb) + MASK64_R(me) + ((me) >= (mb))) +#define DATA32(x) (((x) & 0xffffffffUL) | (((x) & 0xffffffffUL) << 32)) +#else +#define DATA32(x) (x) +#endif +#define ROTATE(x, n) ((n) ? (((x) << (n)) | ((x) >> (8 * sizeof(long) - (n)))) : (x)) + +/* + * Decode an instruction, and execute it if that can be done just by + * modifying *regs (i.e. integer arithmetic and logical instructions, + * branches, and barrier instructions). + * Returns 1 if the instruction has been executed, or 0 if not. + * Sets *op to indicate what the instruction does. + */ +int __kprobes analyse_instr(struct instruction_op *op, struct pt_regs *regs, + unsigned int instr) +{ + unsigned int opcode, ra, rb, rd, spr, u; + unsigned long int imm; + unsigned long int val, val2; + unsigned int mb, me, sh; + long ival; + + op->type = COMPUTE; + + opcode = instr >> 26; + switch (opcode) { + case 16: /* bc */ + op->type = BRANCH; + imm = (signed short)(instr & 0xfffc); + if ((instr & 2) == 0) + imm += regs->nip; + regs->nip += 4; + regs->nip = truncate_if_32bit(regs->msr, regs->nip); + if (instr & 1) + regs->link = regs->nip; + if (branch_taken(instr, regs)) + regs->nip = truncate_if_32bit(regs->msr, imm); + return 1; +#ifdef CONFIG_PPC64 + case 17: /* sc */ + if ((instr & 0xfe2) == 2) + op->type = SYSCALL; + else + op->type = UNKNOWN; + return 0; +#endif + case 18: /* b */ + op->type = BRANCH; + imm = instr & 0x03fffffc; + if (imm & 0x02000000) + imm -= 0x04000000; + if ((instr & 2) == 0) + imm += regs->nip; + if (instr & 1) + regs->link = truncate_if_32bit(regs->msr, regs->nip + 4); + imm = truncate_if_32bit(regs->msr, imm); + regs->nip = imm; + return 1; + case 19: + switch ((instr >> 1) & 0x3ff) { + case 0: /* mcrf */ + rd = (instr >> 21) & 0x1c; + ra = (instr >> 16) & 0x1c; + val = (regs->ccr >> ra) & 0xf; + regs->ccr = (regs->ccr & ~(0xfUL << rd)) | (val << rd); + goto instr_done; + + case 16: /* bclr */ + case 528: /* bcctr */ + op->type = BRANCH; + imm = (instr & 0x400)? regs->ctr: regs->link; + regs->nip = truncate_if_32bit(regs->msr, regs->nip + 4); + imm = truncate_if_32bit(regs->msr, imm); + if (instr & 1) + regs->link = regs->nip; + if (branch_taken(instr, regs)) + regs->nip = imm; + return 1; + + case 18: /* rfid, scary */ + if (regs->msr & MSR_PR) + goto priv; + op->type = RFI; + return 0; + + case 150: /* isync */ + op->type = BARRIER; + isync(); + goto instr_done; + + case 33: /* crnor */ + case 129: /* crandc */ + case 193: /* crxor */ + case 225: /* crnand */ + case 257: /* crand */ + case 289: /* creqv */ + case 417: /* crorc */ + case 449: /* cror */ + ra = (instr >> 16) & 0x1f; + rb = (instr >> 11) & 0x1f; + rd = (instr >> 21) & 0x1f; + ra = (regs->ccr >> (31 - ra)) & 1; + rb = (regs->ccr >> (31 - rb)) & 1; + val = (instr >> (6 + ra * 2 + rb)) & 1; + regs->ccr = (regs->ccr & ~(1UL << (31 - rd))) | + (val << (31 - rd)); + goto instr_done; + } + break; + case 31: + switch ((instr >> 1) & 0x3ff) { + case 598: /* sync */ + op->type = BARRIER; +#ifdef __powerpc64__ + switch ((instr >> 21) & 3) { + case 1: /* lwsync */ + asm volatile("lwsync" : : : "memory"); + goto instr_done; + case 2: /* ptesync */ + asm volatile("ptesync" : : : "memory"); + goto instr_done; + } +#endif + mb(); + goto instr_done; + + case 854: /* eieio */ + op->type = BARRIER; + eieio(); + goto instr_done; + } + break; + } + + /* Following cases refer to regs->gpr[], so we need all regs */ + if (!FULL_REGS(regs)) + return 0; + + rd = (instr >> 21) & 0x1f; + ra = (instr >> 16) & 0x1f; + rb = (instr >> 11) & 0x1f; + + switch (opcode) { +#ifdef __powerpc64__ + case 2: /* tdi */ + if (rd & trap_compare(regs->gpr[ra], (short) instr)) + goto trap; + goto instr_done; +#endif + case 3: /* twi */ + if (rd & trap_compare((int)regs->gpr[ra], (short) instr)) + goto trap; + goto instr_done; + + case 7: /* mulli */ + regs->gpr[rd] = regs->gpr[ra] * (short) instr; + goto instr_done; + + case 8: /* subfic */ + imm = (short) instr; + add_with_carry(regs, rd, ~regs->gpr[ra], imm, 1); + goto instr_done; + + case 10: /* cmpli */ + imm = (unsigned short) instr; + val = regs->gpr[ra]; +#ifdef __powerpc64__ + if ((rd & 1) == 0) + val = (unsigned int) val; +#endif + do_cmp_unsigned(regs, val, imm, rd >> 2); + goto instr_done; + + case 11: /* cmpi */ + imm = (short) instr; + val = regs->gpr[ra]; +#ifdef __powerpc64__ + if ((rd & 1) == 0) + val = (int) val; +#endif + do_cmp_signed(regs, val, imm, rd >> 2); + goto instr_done; + + case 12: /* addic */ + imm = (short) instr; + add_with_carry(regs, rd, regs->gpr[ra], imm, 0); + goto instr_done; + + case 13: /* addic. */ + imm = (short) instr; + add_with_carry(regs, rd, regs->gpr[ra], imm, 0); + set_cr0(regs, rd); + goto instr_done; + + case 14: /* addi */ + imm = (short) instr; + if (ra) + imm += regs->gpr[ra]; + regs->gpr[rd] = imm; + goto instr_done; + + case 15: /* addis */ + imm = ((short) instr) << 16; + if (ra) + imm += regs->gpr[ra]; + regs->gpr[rd] = imm; + goto instr_done; + + case 20: /* rlwimi */ + mb = (instr >> 6) & 0x1f; + me = (instr >> 1) & 0x1f; + val = DATA32(regs->gpr[rd]); + imm = MASK32(mb, me); + regs->gpr[ra] = (regs->gpr[ra] & ~imm) | (ROTATE(val, rb) & imm); + goto logical_done; + + case 21: /* rlwinm */ + mb = (instr >> 6) & 0x1f; + me = (instr >> 1) & 0x1f; + val = DATA32(regs->gpr[rd]); + regs->gpr[ra] = ROTATE(val, rb) & MASK32(mb, me); + goto logical_done; + + case 23: /* rlwnm */ + mb = (instr >> 6) & 0x1f; + me = (instr >> 1) & 0x1f; + rb = regs->gpr[rb] & 0x1f; + val = DATA32(regs->gpr[rd]); + regs->gpr[ra] = ROTATE(val, rb) & MASK32(mb, me); + goto logical_done; + + case 24: /* ori */ + imm = (unsigned short) instr; + regs->gpr[ra] = regs->gpr[rd] | imm; + goto instr_done; + + case 25: /* oris */ + imm = (unsigned short) instr; + regs->gpr[ra] = regs->gpr[rd] | (imm << 16); + goto instr_done; + + case 26: /* xori */ + imm = (unsigned short) instr; + regs->gpr[ra] = regs->gpr[rd] ^ imm; + goto instr_done; + + case 27: /* xoris */ + imm = (unsigned short) instr; + regs->gpr[ra] = regs->gpr[rd] ^ (imm << 16); + goto instr_done; + + case 28: /* andi. */ + imm = (unsigned short) instr; + regs->gpr[ra] = regs->gpr[rd] & imm; + set_cr0(regs, ra); + goto instr_done; + + case 29: /* andis. */ + imm = (unsigned short) instr; + regs->gpr[ra] = regs->gpr[rd] & (imm << 16); + set_cr0(regs, ra); + goto instr_done; + +#ifdef __powerpc64__ + case 30: /* rld* */ + mb = ((instr >> 6) & 0x1f) | (instr & 0x20); + val = regs->gpr[rd]; + if ((instr & 0x10) == 0) { + sh = rb | ((instr & 2) << 4); + val = ROTATE(val, sh); + switch ((instr >> 2) & 3) { + case 0: /* rldicl */ + regs->gpr[ra] = val & MASK64_L(mb); + goto logical_done; + case 1: /* rldicr */ + regs->gpr[ra] = val & MASK64_R(mb); + goto logical_done; + case 2: /* rldic */ + regs->gpr[ra] = val & MASK64(mb, 63 - sh); + goto logical_done; + case 3: /* rldimi */ + imm = MASK64(mb, 63 - sh); + regs->gpr[ra] = (regs->gpr[ra] & ~imm) | + (val & imm); + goto logical_done; + } + } else { + sh = regs->gpr[rb] & 0x3f; + val = ROTATE(val, sh); + switch ((instr >> 1) & 7) { + case 0: /* rldcl */ + regs->gpr[ra] = val & MASK64_L(mb); + goto logical_done; + case 1: /* rldcr */ + regs->gpr[ra] = val & MASK64_R(mb); + goto logical_done; + } + } +#endif + + case 31: + switch ((instr >> 1) & 0x3ff) { + case 4: /* tw */ + if (rd == 0x1f || + (rd & trap_compare((int)regs->gpr[ra], + (int)regs->gpr[rb]))) + goto trap; + goto instr_done; +#ifdef __powerpc64__ + case 68: /* td */ + if (rd & trap_compare(regs->gpr[ra], regs->gpr[rb])) + goto trap; + goto instr_done; +#endif + case 83: /* mfmsr */ + if (regs->msr & MSR_PR) + goto priv; + op->type = MFMSR; + op->reg = rd; + return 0; + case 146: /* mtmsr */ + if (regs->msr & MSR_PR) + goto priv; + op->type = MTMSR; + op->reg = rd; + op->val = 0xffffffff & ~(MSR_ME | MSR_LE); + return 0; +#ifdef CONFIG_PPC64 + case 178: /* mtmsrd */ + if (regs->msr & MSR_PR) + goto priv; + op->type = MTMSR; + op->reg = rd; + /* only MSR_EE and MSR_RI get changed if bit 15 set */ + /* mtmsrd doesn't change MSR_HV, MSR_ME or MSR_LE */ + imm = (instr & 0x10000)? 0x8002: 0xefffffffffffeffeUL; + op->val = imm; + return 0; +#endif + + case 19: /* mfcr */ + regs->gpr[rd] = regs->ccr; + regs->gpr[rd] &= 0xffffffffUL; + goto instr_done; + + case 144: /* mtcrf */ + imm = 0xf0000000UL; + val = regs->gpr[rd]; + for (sh = 0; sh < 8; ++sh) { + if (instr & (0x80000 >> sh)) + regs->ccr = (regs->ccr & ~imm) | + (val & imm); + imm >>= 4; + } + goto instr_done; + + case 339: /* mfspr */ + spr = ((instr >> 16) & 0x1f) | ((instr >> 6) & 0x3e0); + switch (spr) { + case SPRN_XER: /* mfxer */ + regs->gpr[rd] = regs->xer; + regs->gpr[rd] &= 0xffffffffUL; + goto instr_done; + case SPRN_LR: /* mflr */ + regs->gpr[rd] = regs->link; + goto instr_done; + case SPRN_CTR: /* mfctr */ + regs->gpr[rd] = regs->ctr; + goto instr_done; + default: + op->type = MFSPR; + op->reg = rd; + op->spr = spr; + return 0; + } + break; + + case 467: /* mtspr */ + spr = ((instr >> 16) & 0x1f) | ((instr >> 6) & 0x3e0); + switch (spr) { + case SPRN_XER: /* mtxer */ + regs->xer = (regs->gpr[rd] & 0xffffffffUL); + goto instr_done; + case SPRN_LR: /* mtlr */ + regs->link = regs->gpr[rd]; + goto instr_done; + case SPRN_CTR: /* mtctr */ + regs->ctr = regs->gpr[rd]; + goto instr_done; + default: + op->type = MTSPR; + op->val = regs->gpr[rd]; + op->spr = spr; + return 0; + } + break; + +/* + * Compare instructions + */ + case 0: /* cmp */ + val = regs->gpr[ra]; + val2 = regs->gpr[rb]; +#ifdef __powerpc64__ + if ((rd & 1) == 0) { + /* word (32-bit) compare */ + val = (int) val; + val2 = (int) val2; + } +#endif + do_cmp_signed(regs, val, val2, rd >> 2); + goto instr_done; + + case 32: /* cmpl */ + val = regs->gpr[ra]; + val2 = regs->gpr[rb]; +#ifdef __powerpc64__ + if ((rd & 1) == 0) { + /* word (32-bit) compare */ + val = (unsigned int) val; + val2 = (unsigned int) val2; + } +#endif + do_cmp_unsigned(regs, val, val2, rd >> 2); + goto instr_done; + +/* + * Arithmetic instructions + */ + case 8: /* subfc */ + add_with_carry(regs, rd, ~regs->gpr[ra], + regs->gpr[rb], 1); + goto arith_done; +#ifdef __powerpc64__ + case 9: /* mulhdu */ + asm("mulhdu %0,%1,%2" : "=r" (regs->gpr[rd]) : + "r" (regs->gpr[ra]), "r" (regs->gpr[rb])); + goto arith_done; +#endif + case 10: /* addc */ + add_with_carry(regs, rd, regs->gpr[ra], + regs->gpr[rb], 0); + goto arith_done; + + case 11: /* mulhwu */ + asm("mulhwu %0,%1,%2" : "=r" (regs->gpr[rd]) : + "r" (regs->gpr[ra]), "r" (regs->gpr[rb])); + goto arith_done; + + case 40: /* subf */ + regs->gpr[rd] = regs->gpr[rb] - regs->gpr[ra]; + goto arith_done; +#ifdef __powerpc64__ + case 73: /* mulhd */ + asm("mulhd %0,%1,%2" : "=r" (regs->gpr[rd]) : + "r" (regs->gpr[ra]), "r" (regs->gpr[rb])); + goto arith_done; +#endif + case 75: /* mulhw */ + asm("mulhw %0,%1,%2" : "=r" (regs->gpr[rd]) : + "r" (regs->gpr[ra]), "r" (regs->gpr[rb])); + goto arith_done; + + case 104: /* neg */ + regs->gpr[rd] = -regs->gpr[ra]; + goto arith_done; + + case 136: /* subfe */ + add_with_carry(regs, rd, ~regs->gpr[ra], regs->gpr[rb], + regs->xer & XER_CA); + goto arith_done; + + case 138: /* adde */ + add_with_carry(regs, rd, regs->gpr[ra], regs->gpr[rb], + regs->xer & XER_CA); + goto arith_done; + + case 200: /* subfze */ + add_with_carry(regs, rd, ~regs->gpr[ra], 0L, + regs->xer & XER_CA); + goto arith_done; + + case 202: /* addze */ + add_with_carry(regs, rd, regs->gpr[ra], 0L, + regs->xer & XER_CA); + goto arith_done; + + case 232: /* subfme */ + add_with_carry(regs, rd, ~regs->gpr[ra], -1L, + regs->xer & XER_CA); + goto arith_done; +#ifdef __powerpc64__ + case 233: /* mulld */ + regs->gpr[rd] = regs->gpr[ra] * regs->gpr[rb]; + goto arith_done; +#endif + case 234: /* addme */ + add_with_carry(regs, rd, regs->gpr[ra], -1L, + regs->xer & XER_CA); + goto arith_done; + + case 235: /* mullw */ + regs->gpr[rd] = (unsigned int) regs->gpr[ra] * + (unsigned int) regs->gpr[rb]; + goto arith_done; + + case 266: /* add */ + regs->gpr[rd] = regs->gpr[ra] + regs->gpr[rb]; + goto arith_done; +#ifdef __powerpc64__ + case 457: /* divdu */ + regs->gpr[rd] = regs->gpr[ra] / regs->gpr[rb]; + goto arith_done; +#endif + case 459: /* divwu */ + regs->gpr[rd] = (unsigned int) regs->gpr[ra] / + (unsigned int) regs->gpr[rb]; + goto arith_done; +#ifdef __powerpc64__ + case 489: /* divd */ + regs->gpr[rd] = (long int) regs->gpr[ra] / + (long int) regs->gpr[rb]; + goto arith_done; +#endif + case 491: /* divw */ + regs->gpr[rd] = (int) regs->gpr[ra] / + (int) regs->gpr[rb]; + goto arith_done; + + +/* + * Logical instructions + */ + case 26: /* cntlzw */ + asm("cntlzw %0,%1" : "=r" (regs->gpr[ra]) : + "r" (regs->gpr[rd])); + goto logical_done; +#ifdef __powerpc64__ + case 58: /* cntlzd */ + asm("cntlzd %0,%1" : "=r" (regs->gpr[ra]) : + "r" (regs->gpr[rd])); + goto logical_done; +#endif + case 28: /* and */ + regs->gpr[ra] = regs->gpr[rd] & regs->gpr[rb]; + goto logical_done; + + case 60: /* andc */ + regs->gpr[ra] = regs->gpr[rd] & ~regs->gpr[rb]; + goto logical_done; + + case 124: /* nor */ + regs->gpr[ra] = ~(regs->gpr[rd] | regs->gpr[rb]); + goto logical_done; + + case 284: /* xor */ + regs->gpr[ra] = ~(regs->gpr[rd] ^ regs->gpr[rb]); + goto logical_done; + + case 316: /* xor */ + regs->gpr[ra] = regs->gpr[rd] ^ regs->gpr[rb]; + goto logical_done; + + case 412: /* orc */ + regs->gpr[ra] = regs->gpr[rd] | ~regs->gpr[rb]; + goto logical_done; + + case 444: /* or */ + regs->gpr[ra] = regs->gpr[rd] | regs->gpr[rb]; + goto logical_done; + + case 476: /* nand */ + regs->gpr[ra] = ~(regs->gpr[rd] & regs->gpr[rb]); + goto logical_done; + + case 922: /* extsh */ + regs->gpr[ra] = (signed short) regs->gpr[rd]; + goto logical_done; + + case 954: /* extsb */ + regs->gpr[ra] = (signed char) regs->gpr[rd]; + goto logical_done; +#ifdef __powerpc64__ + case 986: /* extsw */ + regs->gpr[ra] = (signed int) regs->gpr[rd]; + goto logical_done; +#endif + +/* + * Shift instructions + */ + case 24: /* slw */ + sh = regs->gpr[rb] & 0x3f; + if (sh < 32) + regs->gpr[ra] = (regs->gpr[rd] << sh) & 0xffffffffUL; + else + regs->gpr[ra] = 0; + goto logical_done; + + case 536: /* srw */ + sh = regs->gpr[rb] & 0x3f; + if (sh < 32) + regs->gpr[ra] = (regs->gpr[rd] & 0xffffffffUL) >> sh; + else + regs->gpr[ra] = 0; + goto logical_done; + + case 792: /* sraw */ + sh = regs->gpr[rb] & 0x3f; + ival = (signed int) regs->gpr[rd]; + regs->gpr[ra] = ival >> (sh < 32 ? sh : 31); + if (ival < 0 && (sh >= 32 || (ival & ((1ul << sh) - 1)) != 0)) + regs->xer |= XER_CA; + else + regs->xer &= ~XER_CA; + goto logical_done; + + case 824: /* srawi */ + sh = rb; + ival = (signed int) regs->gpr[rd]; + regs->gpr[ra] = ival >> sh; + if (ival < 0 && (ival & ((1ul << sh) - 1)) != 0) + regs->xer |= XER_CA; + else + regs->xer &= ~XER_CA; + goto logical_done; + +#ifdef __powerpc64__ + case 27: /* sld */ + sh = regs->gpr[rb] & 0x7f; + if (sh < 64) + regs->gpr[ra] = regs->gpr[rd] << sh; + else + regs->gpr[ra] = 0; + goto logical_done; + + case 539: /* srd */ + sh = regs->gpr[rb] & 0x7f; + if (sh < 64) + regs->gpr[ra] = regs->gpr[rd] >> sh; + else + regs->gpr[ra] = 0; + goto logical_done; + + case 794: /* srad */ + sh = regs->gpr[rb] & 0x7f; + ival = (signed long int) regs->gpr[rd]; + regs->gpr[ra] = ival >> (sh < 64 ? sh : 63); + if (ival < 0 && (sh >= 64 || (ival & ((1ul << sh) - 1)) != 0)) + regs->xer |= XER_CA; + else + regs->xer &= ~XER_CA; + goto logical_done; + + case 826: /* sradi with sh_5 = 0 */ + case 827: /* sradi with sh_5 = 1 */ + sh = rb | ((instr & 2) << 4); + ival = (signed long int) regs->gpr[rd]; + regs->gpr[ra] = ival >> sh; + if (ival < 0 && (ival & ((1ul << sh) - 1)) != 0) + regs->xer |= XER_CA; + else + regs->xer &= ~XER_CA; + goto logical_done; +#endif /* __powerpc64__ */ + +/* + * Cache instructions + */ + case 54: /* dcbst */ + op->type = MKOP(CACHEOP, DCBST, 0); + op->ea = xform_ea(instr, regs); + return 0; + + case 86: /* dcbf */ + op->type = MKOP(CACHEOP, DCBF, 0); + op->ea = xform_ea(instr, regs); + return 0; + + case 246: /* dcbtst */ + op->type = MKOP(CACHEOP, DCBTST, 0); + op->ea = xform_ea(instr, regs); + op->reg = rd; + return 0; + + case 278: /* dcbt */ + op->type = MKOP(CACHEOP, DCBTST, 0); + op->ea = xform_ea(instr, regs); + op->reg = rd; + return 0; + + case 982: /* icbi */ + op->type = MKOP(CACHEOP, ICBI, 0); + op->ea = xform_ea(instr, regs); + return 0; + } + break; + } + + /* + * Loads and stores. + */ + op->type = UNKNOWN; + op->update_reg = ra; + op->reg = rd; + op->val = regs->gpr[rd]; + u = (instr >> 20) & UPDATE; + + switch (opcode) { + case 31: + u = instr & UPDATE; + op->ea = xform_ea(instr, regs); + switch ((instr >> 1) & 0x3ff) { + case 20: /* lwarx */ + op->type = MKOP(LARX, 0, 4); + break; + + case 150: /* stwcx. */ + op->type = MKOP(STCX, 0, 4); + break; + +#ifdef __powerpc64__ + case 84: /* ldarx */ + op->type = MKOP(LARX, 0, 8); + break; + + case 214: /* stdcx. */ + op->type = MKOP(STCX, 0, 8); + break; + + case 21: /* ldx */ + case 53: /* ldux */ + op->type = MKOP(LOAD, u, 8); + break; +#endif + + case 23: /* lwzx */ + case 55: /* lwzux */ + op->type = MKOP(LOAD, u, 4); + break; + + case 87: /* lbzx */ + case 119: /* lbzux */ + op->type = MKOP(LOAD, u, 1); + break; + +#ifdef CONFIG_ALTIVEC + case 103: /* lvx */ + case 359: /* lvxl */ + if (!(regs->msr & MSR_VEC)) + goto vecunavail; + op->type = MKOP(LOAD_VMX, 0, 16); + break; + + case 231: /* stvx */ + case 487: /* stvxl */ + if (!(regs->msr & MSR_VEC)) + goto vecunavail; + op->type = MKOP(STORE_VMX, 0, 16); + break; +#endif /* CONFIG_ALTIVEC */ + +#ifdef __powerpc64__ + case 149: /* stdx */ + case 181: /* stdux */ + op->type = MKOP(STORE, u, 8); + break; +#endif + + case 151: /* stwx */ + case 183: /* stwux */ + op->type = MKOP(STORE, u, 4); + break; + + case 215: /* stbx */ + case 247: /* stbux */ + op->type = MKOP(STORE, u, 1); + break; + + case 279: /* lhzx */ + case 311: /* lhzux */ + op->type = MKOP(LOAD, u, 2); + break; + +#ifdef __powerpc64__ + case 341: /* lwax */ + case 373: /* lwaux */ + op->type = MKOP(LOAD, SIGNEXT | u, 4); + break; +#endif + + case 343: /* lhax */ + case 375: /* lhaux */ + op->type = MKOP(LOAD, SIGNEXT | u, 2); + break; + + case 407: /* sthx */ + case 439: /* sthux */ + op->type = MKOP(STORE, u, 2); + break; + +#ifdef __powerpc64__ + case 532: /* ldbrx */ + op->type = MKOP(LOAD, BYTEREV, 8); + break; + +#endif + case 533: /* lswx */ + op->type = MKOP(LOAD_MULTI, 0, regs->xer & 0x7f); + break; + + case 534: /* lwbrx */ + op->type = MKOP(LOAD, BYTEREV, 4); + break; + + case 597: /* lswi */ + if (rb == 0) + rb = 32; /* # bytes to load */ + op->type = MKOP(LOAD_MULTI, 0, rb); + op->ea = 0; + if (ra) + op->ea = truncate_if_32bit(regs->msr, + regs->gpr[ra]); + break; + +#ifdef CONFIG_PPC_FPU + case 535: /* lfsx */ + case 567: /* lfsux */ + if (!(regs->msr & MSR_FP)) + goto fpunavail; + op->type = MKOP(LOAD_FP, u, 4); + break; + + case 599: /* lfdx */ + case 631: /* lfdux */ + if (!(regs->msr & MSR_FP)) + goto fpunavail; + op->type = MKOP(LOAD_FP, u, 8); + break; + + case 663: /* stfsx */ + case 695: /* stfsux */ + if (!(regs->msr & MSR_FP)) + goto fpunavail; + op->type = MKOP(STORE_FP, u, 4); + break; + + case 727: /* stfdx */ + case 759: /* stfdux */ + if (!(regs->msr & MSR_FP)) + goto fpunavail; + op->type = MKOP(STORE_FP, u, 8); + break; +#endif + +#ifdef __powerpc64__ + case 660: /* stdbrx */ + op->type = MKOP(STORE, BYTEREV, 8); + op->val = byterev_8(regs->gpr[rd]); + break; + +#endif + case 661: /* stswx */ + op->type = MKOP(STORE_MULTI, 0, regs->xer & 0x7f); + break; + + case 662: /* stwbrx */ + op->type = MKOP(STORE, BYTEREV, 4); + op->val = byterev_4(regs->gpr[rd]); + break; + + case 725: + if (rb == 0) + rb = 32; /* # bytes to store */ + op->type = MKOP(STORE_MULTI, 0, rb); + op->ea = 0; + if (ra) + op->ea = truncate_if_32bit(regs->msr, + regs->gpr[ra]); + break; + + case 790: /* lhbrx */ + op->type = MKOP(LOAD, BYTEREV, 2); + break; + + case 918: /* sthbrx */ + op->type = MKOP(STORE, BYTEREV, 2); + op->val = byterev_2(regs->gpr[rd]); + break; + +#ifdef CONFIG_VSX + case 844: /* lxvd2x */ + case 876: /* lxvd2ux */ + if (!(regs->msr & MSR_VSX)) + goto vsxunavail; + op->reg = rd | ((instr & 1) << 5); + op->type = MKOP(LOAD_VSX, u, 16); + break; + + case 972: /* stxvd2x */ + case 1004: /* stxvd2ux */ + if (!(regs->msr & MSR_VSX)) + goto vsxunavail; + op->reg = rd | ((instr & 1) << 5); + op->type = MKOP(STORE_VSX, u, 16); + break; + +#endif /* CONFIG_VSX */ + } + break; + + case 32: /* lwz */ + case 33: /* lwzu */ + op->type = MKOP(LOAD, u, 4); + op->ea = dform_ea(instr, regs); + break; + + case 34: /* lbz */ + case 35: /* lbzu */ + op->type = MKOP(LOAD, u, 1); + op->ea = dform_ea(instr, regs); + break; + + case 36: /* stw */ + case 37: /* stwu */ + op->type = MKOP(STORE, u, 4); + op->ea = dform_ea(instr, regs); + break; + + case 38: /* stb */ + case 39: /* stbu */ + op->type = MKOP(STORE, u, 1); + op->ea = dform_ea(instr, regs); + break; + + case 40: /* lhz */ + case 41: /* lhzu */ + op->type = MKOP(LOAD, u, 2); + op->ea = dform_ea(instr, regs); + break; + + case 42: /* lha */ + case 43: /* lhau */ + op->type = MKOP(LOAD, SIGNEXT | u, 2); + op->ea = dform_ea(instr, regs); + break; + + case 44: /* sth */ + case 45: /* sthu */ + op->type = MKOP(STORE, u, 2); + op->ea = dform_ea(instr, regs); + break; + + case 46: /* lmw */ + if (ra >= rd) + break; /* invalid form, ra in range to load */ + op->type = MKOP(LOAD_MULTI, 0, 4 * (32 - rd)); + op->ea = dform_ea(instr, regs); + break; + + case 47: /* stmw */ + op->type = MKOP(STORE_MULTI, 0, 4 * (32 - rd)); + op->ea = dform_ea(instr, regs); + break; + +#ifdef CONFIG_PPC_FPU + case 48: /* lfs */ + case 49: /* lfsu */ + if (!(regs->msr & MSR_FP)) + goto fpunavail; + op->type = MKOP(LOAD_FP, u, 4); + op->ea = dform_ea(instr, regs); + break; + + case 50: /* lfd */ + case 51: /* lfdu */ + if (!(regs->msr & MSR_FP)) + goto fpunavail; + op->type = MKOP(LOAD_FP, u, 8); + op->ea = dform_ea(instr, regs); + break; + + case 52: /* stfs */ + case 53: /* stfsu */ + if (!(regs->msr & MSR_FP)) + goto fpunavail; + op->type = MKOP(STORE_FP, u, 4); + op->ea = dform_ea(instr, regs); + break; + + case 54: /* stfd */ + case 55: /* stfdu */ + if (!(regs->msr & MSR_FP)) + goto fpunavail; + op->type = MKOP(STORE_FP, u, 8); + op->ea = dform_ea(instr, regs); + break; +#endif + +#ifdef __powerpc64__ + case 58: /* ld[u], lwa */ + op->ea = dsform_ea(instr, regs); + switch (instr & 3) { + case 0: /* ld */ + op->type = MKOP(LOAD, 0, 8); + break; + case 1: /* ldu */ + op->type = MKOP(LOAD, UPDATE, 8); + break; + case 2: /* lwa */ + op->type = MKOP(LOAD, SIGNEXT, 4); + break; + } + break; + + case 62: /* std[u] */ + op->ea = dsform_ea(instr, regs); + switch (instr & 3) { + case 0: /* std */ + op->type = MKOP(STORE, 0, 8); + break; + case 1: /* stdu */ + op->type = MKOP(STORE, UPDATE, 8); + break; + } + break; +#endif /* __powerpc64__ */ + + } + return 0; + + logical_done: + if (instr & 1) + set_cr0(regs, ra); + goto instr_done; + + arith_done: + if (instr & 1) + set_cr0(regs, rd); + + instr_done: + regs->nip = truncate_if_32bit(regs->msr, regs->nip + 4); + return 1; + + priv: + op->type = INTERRUPT | 0x700; + op->val = SRR1_PROGPRIV; + return 0; + + trap: + op->type = INTERRUPT | 0x700; + op->val = SRR1_PROGTRAP; + return 0; + +#ifdef CONFIG_PPC_FPU + fpunavail: + op->type = INTERRUPT | 0x800; + return 0; +#endif + +#ifdef CONFIG_ALTIVEC + vecunavail: + op->type = INTERRUPT | 0xf20; + return 0; +#endif + +#ifdef CONFIG_VSX + vsxunavail: + op->type = INTERRUPT | 0xf40; + return 0; +#endif +} +EXPORT_SYMBOL_GPL(analyse_instr); + +/* + * For PPC32 we always use stwu with r1 to change the stack pointer. + * So this emulated store may corrupt the exception frame, now we + * have to provide the exception frame trampoline, which is pushed + * below the kprobed function stack. So we only update gpr[1] but + * don't emulate the real store operation. We will do real store + * operation safely in exception return code by checking this flag. + */ +static __kprobes int handle_stack_update(unsigned long ea, struct pt_regs *regs) +{ +#ifdef CONFIG_PPC32 + /* + * Check if we will touch kernel stack overflow + */ + if (ea - STACK_INT_FRAME_SIZE <= current->thread.ksp_limit) { + printk(KERN_CRIT "Can't kprobe this since kernel stack would overflow.\n"); + return -EINVAL; + } +#endif /* CONFIG_PPC32 */ + /* + * Check if we already set since that means we'll + * lose the previous value. + */ + WARN_ON(test_thread_flag(TIF_EMULATE_STACK_STORE)); + set_thread_flag(TIF_EMULATE_STACK_STORE); + return 0; +} + +static __kprobes void do_signext(unsigned long *valp, int size) +{ + switch (size) { + case 2: + *valp = (signed short) *valp; + break; + case 4: + *valp = (signed int) *valp; + break; + } +} + +static __kprobes void do_byterev(unsigned long *valp, int size) +{ + switch (size) { + case 2: + *valp = byterev_2(*valp); + break; + case 4: + *valp = byterev_4(*valp); + break; +#ifdef __powerpc64__ + case 8: + *valp = byterev_8(*valp); + break; +#endif + } +} + +/* + * Emulate instructions that cause a transfer of control, + * loads and stores, and a few other instructions. + * Returns 1 if the step was emulated, 0 if not, + * or -1 if the instruction is one that should not be stepped, + * such as an rfid, or a mtmsrd that would clear MSR_RI. + */ +int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr) +{ + struct instruction_op op; + int r, err, size; + unsigned long val; + unsigned int cr; + int i, rd, nb; + + r = analyse_instr(&op, regs, instr); + if (r != 0) + return r; + + err = 0; + size = GETSIZE(op.type); + switch (op.type & INSTR_TYPE_MASK) { + case CACHEOP: + if (!address_ok(regs, op.ea, 8)) + return 0; + switch (op.type & CACHEOP_MASK) { + case DCBST: + __cacheop_user_asmx(op.ea, err, "dcbst"); + break; + case DCBF: + __cacheop_user_asmx(op.ea, err, "dcbf"); + break; + case DCBTST: + if (op.reg == 0) + prefetchw((void *) op.ea); + break; + case DCBT: + if (op.reg == 0) + prefetch((void *) op.ea); + break; + case ICBI: + __cacheop_user_asmx(op.ea, err, "icbi"); + break; + } + if (err) + return 0; + goto instr_done; + + case LARX: + if (regs->msr & MSR_LE) + return 0; + if (op.ea & (size - 1)) + break; /* can't handle misaligned */ + err = -EFAULT; + if (!address_ok(regs, op.ea, size)) + goto ldst_done; + err = 0; + switch (size) { + case 4: + __get_user_asmx(val, op.ea, err, "lwarx"); + break; + case 8: + __get_user_asmx(val, op.ea, err, "ldarx"); + break; + default: + return 0; + } + if (!err) + regs->gpr[op.reg] = val; + goto ldst_done; + + case STCX: + if (regs->msr & MSR_LE) + return 0; + if (op.ea & (size - 1)) + break; /* can't handle misaligned */ + err = -EFAULT; + if (!address_ok(regs, op.ea, size)) + goto ldst_done; + err = 0; + switch (size) { + case 4: + __put_user_asmx(op.val, op.ea, err, "stwcx.", cr); + break; + case 8: + __put_user_asmx(op.val, op.ea, err, "stdcx.", cr); + break; + default: + return 0; + } + if (!err) + regs->ccr = (regs->ccr & 0x0fffffff) | + (cr & 0xe0000000) | + ((regs->xer >> 3) & 0x10000000); + goto ldst_done; + + case LOAD: + if (regs->msr & MSR_LE) + return 0; + err = read_mem(®s->gpr[op.reg], op.ea, size, regs); + if (!err) { + if (op.type & SIGNEXT) + do_signext(®s->gpr[op.reg], size); + if (op.type & BYTEREV) + do_byterev(®s->gpr[op.reg], size); + } + goto ldst_done; + +#ifdef CONFIG_PPC_FPU + case LOAD_FP: + if (regs->msr & MSR_LE) + return 0; + if (size == 4) + err = do_fp_load(op.reg, do_lfs, op.ea, size, regs); + else + err = do_fp_load(op.reg, do_lfd, op.ea, size, regs); + goto ldst_done; +#endif +#ifdef CONFIG_ALTIVEC + case LOAD_VMX: + if (regs->msr & MSR_LE) + return 0; + err = do_vec_load(op.reg, do_lvx, op.ea & ~0xfUL, regs); + goto ldst_done; +#endif +#ifdef CONFIG_VSX + case LOAD_VSX: + if (regs->msr & MSR_LE) + return 0; + err = do_vsx_load(op.reg, do_lxvd2x, op.ea, regs); + goto ldst_done; +#endif + case LOAD_MULTI: + if (regs->msr & MSR_LE) + return 0; + rd = op.reg; + for (i = 0; i < size; i += 4) { + nb = size - i; + if (nb > 4) + nb = 4; + err = read_mem(®s->gpr[rd], op.ea, nb, regs); + if (err) + return 0; + if (nb < 4) /* left-justify last bytes */ + regs->gpr[rd] <<= 32 - 8 * nb; + op.ea += 4; + ++rd; + } + goto instr_done; + + case STORE: + if (regs->msr & MSR_LE) + return 0; + if ((op.type & UPDATE) && size == sizeof(long) && + op.reg == 1 && op.update_reg == 1 && + !(regs->msr & MSR_PR) && + op.ea >= regs->gpr[1] - STACK_INT_FRAME_SIZE) { + err = handle_stack_update(op.ea, regs); + goto ldst_done; + } + err = write_mem(op.val, op.ea, size, regs); + goto ldst_done; + +#ifdef CONFIG_PPC_FPU + case STORE_FP: + if (regs->msr & MSR_LE) + return 0; + if (size == 4) + err = do_fp_store(op.reg, do_stfs, op.ea, size, regs); + else + err = do_fp_store(op.reg, do_stfd, op.ea, size, regs); + goto ldst_done; +#endif +#ifdef CONFIG_ALTIVEC + case STORE_VMX: + if (regs->msr & MSR_LE) + return 0; + err = do_vec_store(op.reg, do_stvx, op.ea & ~0xfUL, regs); + goto ldst_done; +#endif +#ifdef CONFIG_VSX + case STORE_VSX: + if (regs->msr & MSR_LE) + return 0; + err = do_vsx_store(op.reg, do_stxvd2x, op.ea, regs); + goto ldst_done; +#endif + case STORE_MULTI: + if (regs->msr & MSR_LE) + return 0; + rd = op.reg; + for (i = 0; i < size; i += 4) { + val = regs->gpr[rd]; + nb = size - i; + if (nb > 4) + nb = 4; + else + val >>= 32 - 8 * nb; + err = write_mem(val, op.ea, nb, regs); + if (err) + return 0; + op.ea += 4; + ++rd; + } + goto instr_done; + + case MFMSR: + regs->gpr[op.reg] = regs->msr & MSR_MASK; + goto instr_done; + + case MTMSR: + val = regs->gpr[op.reg]; + if ((val & MSR_RI) == 0) + /* can't step mtmsr[d] that would clear MSR_RI */ + return -1; + /* here op.val is the mask of bits to change */ + regs->msr = (regs->msr & ~op.val) | (val & op.val); + goto instr_done; + +#ifdef CONFIG_PPC64 + case SYSCALL: /* sc */ + /* + * N.B. this uses knowledge about how the syscall + * entry code works. If that is changed, this will + * need to be changed also. + */ + if (regs->gpr[0] == 0x1ebe && + cpu_has_feature(CPU_FTR_REAL_LE)) { + regs->msr ^= MSR_LE; + goto instr_done; + } + regs->gpr[9] = regs->gpr[13]; + regs->gpr[10] = MSR_KERNEL; + regs->gpr[11] = regs->nip + 4; + regs->gpr[12] = regs->msr & MSR_MASK; + regs->gpr[13] = (unsigned long) get_paca(); + regs->nip = (unsigned long) &system_call_common; + regs->msr = MSR_KERNEL; + return 1; + + case RFI: + return -1; +#endif + } + return 0; + + ldst_done: + if (err) + return 0; + if (op.type & UPDATE) + regs->gpr[op.update_reg] = op.ea; + + instr_done: + regs->nip = truncate_if_32bit(regs->msr, regs->nip + 4); + return 1; +} |