zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/arch/arm/kernel/kprobes-common.c b/ap/os/linux/linux-3.4.x/arch/arm/kernel/kprobes-common.c
new file mode 100644
index 0000000..18a7628
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/arch/arm/kernel/kprobes-common.c
@@ -0,0 +1,578 @@
+/*
+ * arch/arm/kernel/kprobes-common.c
+ *
+ * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>.
+ *
+ * Some contents moved here from arch/arm/include/asm/kprobes-arm.c which is
+ * Copyright (C) 2006, 2007 Motorola Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/kprobes.h>
+#include <asm/system_info.h>
+
+#include "kprobes.h"
+
+
+#ifndef find_str_pc_offset
+
+/*
+ * For STR and STM instructions, an ARM core may choose to use either
+ * a +8 or a +12 displacement from the current instruction's address.
+ * Whichever value is chosen for a given core, it must be the same for
+ * both instructions and may not change. This function measures it.
+ */
+
+int str_pc_offset;
+
+void __init find_str_pc_offset(void)
+{
+ int addr, scratch, ret;
+
+ __asm__ (
+ "sub %[ret], pc, #4 \n\t"
+ "str pc, %[addr] \n\t"
+ "ldr %[scr], %[addr] \n\t"
+ "sub %[ret], %[scr], %[ret] \n\t"
+ : [ret] "=r" (ret), [scr] "=r" (scratch), [addr] "+m" (addr));
+
+ str_pc_offset = ret;
+}
+
+#endif /* !find_str_pc_offset */
+
+
+#ifndef test_load_write_pc_interworking
+
+bool load_write_pc_interworks;
+
+void __init test_load_write_pc_interworking(void)
+{
+ int arch = cpu_architecture();
+ BUG_ON(arch == CPU_ARCH_UNKNOWN);
+ load_write_pc_interworks = arch >= CPU_ARCH_ARMv5T;
+}
+
+#endif /* !test_load_write_pc_interworking */
+
+
+#ifndef test_alu_write_pc_interworking
+
+bool alu_write_pc_interworks;
+
+void __init test_alu_write_pc_interworking(void)
+{
+ int arch = cpu_architecture();
+ BUG_ON(arch == CPU_ARCH_UNKNOWN);
+ alu_write_pc_interworks = arch >= CPU_ARCH_ARMv7;
+}
+
+#endif /* !test_alu_write_pc_interworking */
+
+
+void __init arm_kprobe_decode_init(void)
+{
+ find_str_pc_offset();
+ test_load_write_pc_interworking();
+ test_alu_write_pc_interworking();
+}
+
+
+static unsigned long __kprobes __check_eq(unsigned long cpsr)
+{
+ return cpsr & PSR_Z_BIT;
+}
+
+static unsigned long __kprobes __check_ne(unsigned long cpsr)
+{
+ return (~cpsr) & PSR_Z_BIT;
+}
+
+static unsigned long __kprobes __check_cs(unsigned long cpsr)
+{
+ return cpsr & PSR_C_BIT;
+}
+
+static unsigned long __kprobes __check_cc(unsigned long cpsr)
+{
+ return (~cpsr) & PSR_C_BIT;
+}
+
+static unsigned long __kprobes __check_mi(unsigned long cpsr)
+{
+ return cpsr & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_pl(unsigned long cpsr)
+{
+ return (~cpsr) & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_vs(unsigned long cpsr)
+{
+ return cpsr & PSR_V_BIT;
+}
+
+static unsigned long __kprobes __check_vc(unsigned long cpsr)
+{
+ return (~cpsr) & PSR_V_BIT;
+}
+
+static unsigned long __kprobes __check_hi(unsigned long cpsr)
+{
+ cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
+ return cpsr & PSR_C_BIT;
+}
+
+static unsigned long __kprobes __check_ls(unsigned long cpsr)
+{
+ cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
+ return (~cpsr) & PSR_C_BIT;
+}
+
+static unsigned long __kprobes __check_ge(unsigned long cpsr)
+{
+ cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+ return (~cpsr) & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_lt(unsigned long cpsr)
+{
+ cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+ return cpsr & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_gt(unsigned long cpsr)
+{
+ unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+ temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */
+ return (~temp) & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_le(unsigned long cpsr)
+{
+ unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+ temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */
+ return temp & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_al(unsigned long cpsr)
+{
+ return true;
+}
+
+kprobe_check_cc * const kprobe_condition_checks[16] = {
+ &__check_eq, &__check_ne, &__check_cs, &__check_cc,
+ &__check_mi, &__check_pl, &__check_vs, &__check_vc,
+ &__check_hi, &__check_ls, &__check_ge, &__check_lt,
+ &__check_gt, &__check_le, &__check_al, &__check_al
+};
+
+
+void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs)
+{
+}
+
+void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs)
+{
+ p->ainsn.insn_fn();
+}
+
+static void __kprobes simulate_ldm1stm1(struct kprobe *p, struct pt_regs *regs)
+{
+ kprobe_opcode_t insn = p->opcode;
+ int rn = (insn >> 16) & 0xf;
+ int lbit = insn & (1 << 20);
+ int wbit = insn & (1 << 21);
+ int ubit = insn & (1 << 23);
+ int pbit = insn & (1 << 24);
+ long *addr = (long *)regs->uregs[rn];
+ int reg_bit_vector;
+ int reg_count;
+
+ reg_count = 0;
+ reg_bit_vector = insn & 0xffff;
+ while (reg_bit_vector) {
+ reg_bit_vector &= (reg_bit_vector - 1);
+ ++reg_count;
+ }
+
+ if (!ubit)
+ addr -= reg_count;
+ addr += (!pbit == !ubit);
+
+ reg_bit_vector = insn & 0xffff;
+ while (reg_bit_vector) {
+ int reg = __ffs(reg_bit_vector);
+ reg_bit_vector &= (reg_bit_vector - 1);
+ if (lbit)
+ regs->uregs[reg] = *addr++;
+ else
+ *addr++ = regs->uregs[reg];
+ }
+
+ if (wbit) {
+ if (!ubit)
+ addr -= reg_count;
+ addr -= (!pbit == !ubit);
+ regs->uregs[rn] = (long)addr;
+ }
+}
+
+static void __kprobes simulate_stm1_pc(struct kprobe *p, struct pt_regs *regs)
+{
+ regs->ARM_pc = (long)p->addr + str_pc_offset;
+ simulate_ldm1stm1(p, regs);
+ regs->ARM_pc = (long)p->addr + 4;
+}
+
+static void __kprobes simulate_ldm1_pc(struct kprobe *p, struct pt_regs *regs)
+{
+ simulate_ldm1stm1(p, regs);
+ load_write_pc(regs->ARM_pc, regs);
+}
+
+static void __kprobes
+emulate_generic_r0_12_noflags(struct kprobe *p, struct pt_regs *regs)
+{
+ register void *rregs asm("r1") = regs;
+ register void *rfn asm("lr") = p->ainsn.insn_fn;
+
+ __asm__ __volatile__ (
+ "stmdb sp!, {%[regs], r11} \n\t"
+ "ldmia %[regs], {r0-r12} \n\t"
+#if __LINUX_ARM_ARCH__ >= 6
+ "blx %[fn] \n\t"
+#else
+ "str %[fn], [sp, #-4]! \n\t"
+ "adr lr, 1f \n\t"
+ "ldr pc, [sp], #4 \n\t"
+ "1: \n\t"
+#endif
+ "ldr lr, [sp], #4 \n\t" /* lr = regs */
+ "stmia lr, {r0-r12} \n\t"
+ "ldr r11, [sp], #4 \n\t"
+ : [regs] "=r" (rregs), [fn] "=r" (rfn)
+ : "0" (rregs), "1" (rfn)
+ : "r0", "r2", "r3", "r4", "r5", "r6", "r7",
+ "r8", "r9", "r10", "r12", "memory", "cc"
+ );
+}
+
+static void __kprobes
+emulate_generic_r2_14_noflags(struct kprobe *p, struct pt_regs *regs)
+{
+ emulate_generic_r0_12_noflags(p, (struct pt_regs *)(regs->uregs+2));
+}
+
+static void __kprobes
+emulate_ldm_r3_15(struct kprobe *p, struct pt_regs *regs)
+{
+ emulate_generic_r0_12_noflags(p, (struct pt_regs *)(regs->uregs+3));
+ load_write_pc(regs->ARM_pc, regs);
+}
+
+enum kprobe_insn __kprobes
+kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi)
+{
+ kprobe_insn_handler_t *handler = 0;
+ unsigned reglist = insn & 0xffff;
+ int is_ldm = insn & 0x100000;
+ int rn = (insn >> 16) & 0xf;
+
+ if (rn <= 12 && (reglist & 0xe000) == 0) {
+ /* Instruction only uses registers in the range R0..R12 */
+ handler = emulate_generic_r0_12_noflags;
+
+ } else if (rn >= 2 && (reglist & 0x8003) == 0) {
+ /* Instruction only uses registers in the range R2..R14 */
+ rn -= 2;
+ reglist >>= 2;
+ handler = emulate_generic_r2_14_noflags;
+
+ } else if (rn >= 3 && (reglist & 0x0007) == 0) {
+ /* Instruction only uses registers in the range R3..R15 */
+ if (is_ldm && (reglist & 0x8000)) {
+ rn -= 3;
+ reglist >>= 3;
+ handler = emulate_ldm_r3_15;
+ }
+ }
+
+ if (handler) {
+ /* We can emulate the instruction in (possibly) modified form */
+ asi->insn[0] = (insn & 0xfff00000) | (rn << 16) | reglist;
+ asi->insn_handler = handler;
+ return INSN_GOOD;
+ }
+
+ /* Fallback to slower simulation... */
+ if (reglist & 0x8000)
+ handler = is_ldm ? simulate_ldm1_pc : simulate_stm1_pc;
+ else
+ handler = simulate_ldm1stm1;
+ asi->insn_handler = handler;
+ return INSN_GOOD_NO_SLOT;
+}
+
+
+/*
+ * Prepare an instruction slot to receive an instruction for emulating.
+ * This is done by placing a subroutine return after the location where the
+ * instruction will be placed. We also modify ARM instructions to be
+ * unconditional as the condition code will already be checked before any
+ * emulation handler is called.
+ */
+static kprobe_opcode_t __kprobes
+prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
+ bool thumb)
+{
+#ifdef CONFIG_THUMB2_KERNEL
+ if (thumb) {
+ u16 *thumb_insn = (u16 *)asi->insn;
+ thumb_insn[1] = 0x4770; /* Thumb bx lr */
+ thumb_insn[2] = 0x4770; /* Thumb bx lr */
+ return insn;
+ }
+ asi->insn[1] = 0xe12fff1e; /* ARM bx lr */
+#else
+ asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */
+#endif
+ /* Make an ARM instruction unconditional */
+ if (insn < 0xe0000000)
+ insn = (insn | 0xe0000000) & ~0x10000000;
+ return insn;
+}
+
+/*
+ * Write a (probably modified) instruction into the slot previously prepared by
+ * prepare_emulated_insn
+ */
+static void __kprobes
+set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
+ bool thumb)
+{
+#ifdef CONFIG_THUMB2_KERNEL
+ if (thumb) {
+ u16 *ip = (u16 *)asi->insn;
+ if (is_wide_instruction(insn))
+ *ip++ = insn >> 16;
+ *ip++ = insn;
+ return;
+ }
+#endif
+ asi->insn[0] = insn;
+}
+
+/*
+ * When we modify the register numbers encoded in an instruction to be emulated,
+ * the new values come from this define. For ARM and 32-bit Thumb instructions
+ * this gives...
+ *
+ * bit position 16 12 8 4 0
+ * ---------------+---+---+---+---+---+
+ * register r2 r0 r1 -- r3
+ */
+#define INSN_NEW_BITS 0x00020103
+
+/* Each nibble has same value as that at INSN_NEW_BITS bit 16 */
+#define INSN_SAMEAS16_BITS 0x22222222
+
+/*
+ * Validate and modify each of the registers encoded in an instruction.
+ *
+ * Each nibble in regs contains a value from enum decode_reg_type. For each
+ * non-zero value, the corresponding nibble in pinsn is validated and modified
+ * according to the type.
+ */
+static bool __kprobes decode_regs(kprobe_opcode_t* pinsn, u32 regs)
+{
+ kprobe_opcode_t insn = *pinsn;
+ kprobe_opcode_t mask = 0xf; /* Start at least significant nibble */
+
+ for (; regs != 0; regs >>= 4, mask <<= 4) {
+
+ kprobe_opcode_t new_bits = INSN_NEW_BITS;
+
+ switch (regs & 0xf) {
+
+ case REG_TYPE_NONE:
+ /* Nibble not a register, skip to next */
+ continue;
+
+ case REG_TYPE_ANY:
+ /* Any register is allowed */
+ break;
+
+ case REG_TYPE_SAMEAS16:
+ /* Replace register with same as at bit position 16 */
+ new_bits = INSN_SAMEAS16_BITS;
+ break;
+
+ case REG_TYPE_SP:
+ /* Only allow SP (R13) */
+ if ((insn ^ 0xdddddddd) & mask)
+ goto reject;
+ break;
+
+ case REG_TYPE_PC:
+ /* Only allow PC (R15) */
+ if ((insn ^ 0xffffffff) & mask)
+ goto reject;
+ break;
+
+ case REG_TYPE_NOSP:
+ /* Reject SP (R13) */
+ if (((insn ^ 0xdddddddd) & mask) == 0)
+ goto reject;
+ break;
+
+ case REG_TYPE_NOSPPC:
+ case REG_TYPE_NOSPPCX:
+ /* Reject SP and PC (R13 and R15) */
+ if (((insn ^ 0xdddddddd) & 0xdddddddd & mask) == 0)
+ goto reject;
+ break;
+
+ case REG_TYPE_NOPCWB:
+ if (!is_writeback(insn))
+ break; /* No writeback, so any register is OK */
+ /* fall through... */
+ case REG_TYPE_NOPC:
+ case REG_TYPE_NOPCX:
+ /* Reject PC (R15) */
+ if (((insn ^ 0xffffffff) & mask) == 0)
+ goto reject;
+ break;
+ }
+
+ /* Replace value of nibble with new register number... */
+ insn &= ~mask;
+ insn |= new_bits & mask;
+ }
+
+ *pinsn = insn;
+ return true;
+
+reject:
+ return false;
+}
+
+static const int decode_struct_sizes[NUM_DECODE_TYPES] = {
+ [DECODE_TYPE_TABLE] = sizeof(struct decode_table),
+ [DECODE_TYPE_CUSTOM] = sizeof(struct decode_custom),
+ [DECODE_TYPE_SIMULATE] = sizeof(struct decode_simulate),
+ [DECODE_TYPE_EMULATE] = sizeof(struct decode_emulate),
+ [DECODE_TYPE_OR] = sizeof(struct decode_or),
+ [DECODE_TYPE_REJECT] = sizeof(struct decode_reject)
+};
+
+/*
+ * kprobe_decode_insn operates on data tables in order to decode an ARM
+ * architecture instruction onto which a kprobe has been placed.
+ *
+ * These instruction decoding tables are a concatenation of entries each
+ * of which consist of one of the following structs:
+ *
+ * decode_table
+ * decode_custom
+ * decode_simulate
+ * decode_emulate
+ * decode_or
+ * decode_reject
+ *
+ * Each of these starts with a struct decode_header which has the following
+ * fields:
+ *
+ * type_regs
+ * mask
+ * value
+ *
+ * The least significant DECODE_TYPE_BITS of type_regs contains a value
+ * from enum decode_type, this indicates which of the decode_* structs
+ * the entry contains. The value DECODE_TYPE_END indicates the end of the
+ * table.
+ *
+ * When the table is parsed, each entry is checked in turn to see if it
+ * matches the instruction to be decoded using the test:
+ *
+ * (insn & mask) == value
+ *
+ * If no match is found before the end of the table is reached then decoding
+ * fails with INSN_REJECTED.
+ *
+ * When a match is found, decode_regs() is called to validate and modify each
+ * of the registers encoded in the instruction; the data it uses to do this
+ * is (type_regs >> DECODE_TYPE_BITS). A validation failure will cause decoding
+ * to fail with INSN_REJECTED.
+ *
+ * Once the instruction has passed the above tests, further processing
+ * depends on the type of the table entry's decode struct.
+ *
+ */
+int __kprobes
+kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
+ const union decode_item *table, bool thumb)
+{
+ const struct decode_header *h = (struct decode_header *)table;
+ const struct decode_header *next;
+ bool matched = false;
+
+ insn = prepare_emulated_insn(insn, asi, thumb);
+
+ for (;; h = next) {
+ enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK;
+ u32 regs = h->type_regs.bits >> DECODE_TYPE_BITS;
+
+ if (type == DECODE_TYPE_END)
+ return INSN_REJECTED;
+
+ next = (struct decode_header *)
+ ((uintptr_t)h + decode_struct_sizes[type]);
+
+ if (!matched && (insn & h->mask.bits) != h->value.bits)
+ continue;
+
+ if (!decode_regs(&insn, regs))
+ return INSN_REJECTED;
+
+ switch (type) {
+
+ case DECODE_TYPE_TABLE: {
+ struct decode_table *d = (struct decode_table *)h;
+ next = (struct decode_header *)d->table.table;
+ break;
+ }
+
+ case DECODE_TYPE_CUSTOM: {
+ struct decode_custom *d = (struct decode_custom *)h;
+ return (*d->decoder.decoder)(insn, asi);
+ }
+
+ case DECODE_TYPE_SIMULATE: {
+ struct decode_simulate *d = (struct decode_simulate *)h;
+ asi->insn_handler = d->handler.handler;
+ return INSN_GOOD_NO_SLOT;
+ }
+
+ case DECODE_TYPE_EMULATE: {
+ struct decode_emulate *d = (struct decode_emulate *)h;
+ asi->insn_handler = d->handler.handler;
+ set_emulated_insn(insn, asi, thumb);
+ return INSN_GOOD;
+ }
+
+ case DECODE_TYPE_OR:
+ matched = true;
+ break;
+
+ case DECODE_TYPE_REJECT:
+ default:
+ return INSN_REJECTED;
+ }
+ }
+ }