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Diffstat (limited to 'ANDROID_3.4.5/arch/arm/kernel/unwind.c')
-rw-r--r--ANDROID_3.4.5/arch/arm/kernel/unwind.c491
1 files changed, 0 insertions, 491 deletions
diff --git a/ANDROID_3.4.5/arch/arm/kernel/unwind.c b/ANDROID_3.4.5/arch/arm/kernel/unwind.c
deleted file mode 100644
index 00df012c..00000000
--- a/ANDROID_3.4.5/arch/arm/kernel/unwind.c
+++ /dev/null
@@ -1,491 +0,0 @@
-/*
- * arch/arm/kernel/unwind.c
- *
- * Copyright (C) 2008 ARM Limited
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- *
- * Stack unwinding support for ARM
- *
- * An ARM EABI version of gcc is required to generate the unwind
- * tables. For information about the structure of the unwind tables,
- * see "Exception Handling ABI for the ARM Architecture" at:
- *
- * http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html
- */
-
-#ifndef __CHECKER__
-#if !defined (__ARM_EABI__)
-#warning Your compiler does not have EABI support.
-#warning ARM unwind is known to compile only with EABI compilers.
-#warning Change compiler or disable ARM_UNWIND option.
-#elif (__GNUC__ == 4 && __GNUC_MINOR__ <= 2)
-#warning Your compiler is too buggy; it is known to not compile ARM unwind support.
-#warning Change compiler or disable ARM_UNWIND option.
-#endif
-#endif /* __CHECKER__ */
-
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/export.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/list.h>
-
-#include <asm/stacktrace.h>
-#include <asm/traps.h>
-#include <asm/unwind.h>
-
-/* Dummy functions to avoid linker complaints */
-void __aeabi_unwind_cpp_pr0(void)
-{
-};
-EXPORT_SYMBOL(__aeabi_unwind_cpp_pr0);
-
-void __aeabi_unwind_cpp_pr1(void)
-{
-};
-EXPORT_SYMBOL(__aeabi_unwind_cpp_pr1);
-
-void __aeabi_unwind_cpp_pr2(void)
-{
-};
-EXPORT_SYMBOL(__aeabi_unwind_cpp_pr2);
-
-struct unwind_ctrl_block {
- unsigned long vrs[16]; /* virtual register set */
- const unsigned long *insn; /* pointer to the current instructions word */
- int entries; /* number of entries left to interpret */
- int byte; /* current byte number in the instructions word */
-};
-
-enum regs {
-#ifdef CONFIG_THUMB2_KERNEL
- FP = 7,
-#else
- FP = 11,
-#endif
- SP = 13,
- LR = 14,
- PC = 15
-};
-
-extern const struct unwind_idx __start_unwind_idx[];
-static const struct unwind_idx *__origin_unwind_idx;
-extern const struct unwind_idx __stop_unwind_idx[];
-
-static DEFINE_SPINLOCK(unwind_lock);
-static LIST_HEAD(unwind_tables);
-
-/* Convert a prel31 symbol to an absolute address */
-#define prel31_to_addr(ptr) \
-({ \
- /* sign-extend to 32 bits */ \
- long offset = (((long)*(ptr)) << 1) >> 1; \
- (unsigned long)(ptr) + offset; \
-})
-
-/*
- * Binary search in the unwind index. The entries are
- * guaranteed to be sorted in ascending order by the linker.
- *
- * start = first entry
- * origin = first entry with positive offset (or stop if there is no such entry)
- * stop - 1 = last entry
- */
-static const struct unwind_idx *search_index(unsigned long addr,
- const struct unwind_idx *start,
- const struct unwind_idx *origin,
- const struct unwind_idx *stop)
-{
- unsigned long addr_prel31;
-
- pr_debug("%s(%08lx, %p, %p, %p)\n",
- __func__, addr, start, origin, stop);
-
- /*
- * only search in the section with the matching sign. This way the
- * prel31 numbers can be compared as unsigned longs.
- */
- if (addr < (unsigned long)start)
- /* negative offsets: [start; origin) */
- stop = origin;
- else
- /* positive offsets: [origin; stop) */
- start = origin;
-
- /* prel31 for address relavive to start */
- addr_prel31 = (addr - (unsigned long)start) & 0x7fffffff;
-
- while (start < stop - 1) {
- const struct unwind_idx *mid = start + ((stop - start) >> 1);
-
- /*
- * As addr_prel31 is relative to start an offset is needed to
- * make it relative to mid.
- */
- if (addr_prel31 - ((unsigned long)mid - (unsigned long)start) <
- mid->addr_offset)
- stop = mid;
- else {
- /* keep addr_prel31 relative to start */
- addr_prel31 -= ((unsigned long)mid -
- (unsigned long)start);
- start = mid;
- }
- }
-
- if (likely(start->addr_offset <= addr_prel31))
- return start;
- else {
- pr_warning("unwind: Unknown symbol address %08lx\n", addr);
- return NULL;
- }
-}
-
-static const struct unwind_idx *unwind_find_origin(
- const struct unwind_idx *start, const struct unwind_idx *stop)
-{
- pr_debug("%s(%p, %p)\n", __func__, start, stop);
- while (start < stop) {
- const struct unwind_idx *mid = start + ((stop - start) >> 1);
-
- if (mid->addr_offset >= 0x40000000)
- /* negative offset */
- start = mid + 1;
- else
- /* positive offset */
- stop = mid;
- }
- pr_debug("%s -> %p\n", __func__, stop);
- return stop;
-}
-
-static const struct unwind_idx *unwind_find_idx(unsigned long addr)
-{
- const struct unwind_idx *idx = NULL;
- unsigned long flags;
-
- pr_debug("%s(%08lx)\n", __func__, addr);
-
- if (core_kernel_text(addr)) {
- if (unlikely(!__origin_unwind_idx))
- __origin_unwind_idx =
- unwind_find_origin(__start_unwind_idx,
- __stop_unwind_idx);
-
- /* main unwind table */
- idx = search_index(addr, __start_unwind_idx,
- __origin_unwind_idx,
- __stop_unwind_idx);
- } else {
- /* module unwind tables */
- struct unwind_table *table;
-
- spin_lock_irqsave(&unwind_lock, flags);
- list_for_each_entry(table, &unwind_tables, list) {
- if (addr >= table->begin_addr &&
- addr < table->end_addr) {
- idx = search_index(addr, table->start,
- table->origin,
- table->stop);
- /* Move-to-front to exploit common traces */
- list_move(&table->list, &unwind_tables);
- break;
- }
- }
- spin_unlock_irqrestore(&unwind_lock, flags);
- }
-
- pr_debug("%s: idx = %p\n", __func__, idx);
- return idx;
-}
-
-static unsigned long unwind_get_byte(struct unwind_ctrl_block *ctrl)
-{
- unsigned long ret;
-
- if (ctrl->entries <= 0) {
- pr_warning("unwind: Corrupt unwind table\n");
- return 0;
- }
-
- ret = (*ctrl->insn >> (ctrl->byte * 8)) & 0xff;
-
- if (ctrl->byte == 0) {
- ctrl->insn++;
- ctrl->entries--;
- ctrl->byte = 3;
- } else
- ctrl->byte--;
-
- return ret;
-}
-
-/*
- * Execute the current unwind instruction.
- */
-static int unwind_exec_insn(struct unwind_ctrl_block *ctrl)
-{
- unsigned long insn = unwind_get_byte(ctrl);
-
- pr_debug("%s: insn = %08lx\n", __func__, insn);
-
- if ((insn & 0xc0) == 0x00)
- ctrl->vrs[SP] += ((insn & 0x3f) << 2) + 4;
- else if ((insn & 0xc0) == 0x40)
- ctrl->vrs[SP] -= ((insn & 0x3f) << 2) + 4;
- else if ((insn & 0xf0) == 0x80) {
- unsigned long mask;
- unsigned long *vsp = (unsigned long *)ctrl->vrs[SP];
- int load_sp, reg = 4;
-
- insn = (insn << 8) | unwind_get_byte(ctrl);
- mask = insn & 0x0fff;
- if (mask == 0) {
- pr_warning("unwind: 'Refuse to unwind' instruction %04lx\n",
- insn);
- return -URC_FAILURE;
- }
-
- /* pop R4-R15 according to mask */
- load_sp = mask & (1 << (13 - 4));
- while (mask) {
- if (mask & 1)
- ctrl->vrs[reg] = *vsp++;
- mask >>= 1;
- reg++;
- }
- if (!load_sp)
- ctrl->vrs[SP] = (unsigned long)vsp;
- } else if ((insn & 0xf0) == 0x90 &&
- (insn & 0x0d) != 0x0d)
- ctrl->vrs[SP] = ctrl->vrs[insn & 0x0f];
- else if ((insn & 0xf0) == 0xa0) {
- unsigned long *vsp = (unsigned long *)ctrl->vrs[SP];
- int reg;
-
- /* pop R4-R[4+bbb] */
- for (reg = 4; reg <= 4 + (insn & 7); reg++)
- ctrl->vrs[reg] = *vsp++;
- if (insn & 0x80)
- ctrl->vrs[14] = *vsp++;
- ctrl->vrs[SP] = (unsigned long)vsp;
- } else if (insn == 0xb0) {
- if (ctrl->vrs[PC] == 0)
- ctrl->vrs[PC] = ctrl->vrs[LR];
- /* no further processing */
- ctrl->entries = 0;
- } else if (insn == 0xb1) {
- unsigned long mask = unwind_get_byte(ctrl);
- unsigned long *vsp = (unsigned long *)ctrl->vrs[SP];
- int reg = 0;
-
- if (mask == 0 || mask & 0xf0) {
- pr_warning("unwind: Spare encoding %04lx\n",
- (insn << 8) | mask);
- return -URC_FAILURE;
- }
-
- /* pop R0-R3 according to mask */
- while (mask) {
- if (mask & 1)
- ctrl->vrs[reg] = *vsp++;
- mask >>= 1;
- reg++;
- }
- ctrl->vrs[SP] = (unsigned long)vsp;
- } else if (insn == 0xb2) {
- unsigned long uleb128 = unwind_get_byte(ctrl);
-
- ctrl->vrs[SP] += 0x204 + (uleb128 << 2);
- } else {
- pr_warning("unwind: Unhandled instruction %02lx\n", insn);
- return -URC_FAILURE;
- }
-
- pr_debug("%s: fp = %08lx sp = %08lx lr = %08lx pc = %08lx\n", __func__,
- ctrl->vrs[FP], ctrl->vrs[SP], ctrl->vrs[LR], ctrl->vrs[PC]);
-
- return URC_OK;
-}
-
-/*
- * Unwind a single frame starting with *sp for the symbol at *pc. It
- * updates the *pc and *sp with the new values.
- */
-int unwind_frame(struct stackframe *frame)
-{
- unsigned long high, low;
- const struct unwind_idx *idx;
- struct unwind_ctrl_block ctrl;
-
- /* only go to a higher address on the stack */
- low = frame->sp;
- high = ALIGN(low, THREAD_SIZE);
-
- pr_debug("%s(pc = %08lx lr = %08lx sp = %08lx)\n", __func__,
- frame->pc, frame->lr, frame->sp);
-
- if (!kernel_text_address(frame->pc))
- return -URC_FAILURE;
-
- idx = unwind_find_idx(frame->pc);
- if (!idx) {
- pr_warning("unwind: Index not found %08lx\n", frame->pc);
- return -URC_FAILURE;
- }
-
- ctrl.vrs[FP] = frame->fp;
- ctrl.vrs[SP] = frame->sp;
- ctrl.vrs[LR] = frame->lr;
- ctrl.vrs[PC] = 0;
-
- if (idx->insn == 1)
- /* can't unwind */
- return -URC_FAILURE;
- else if ((idx->insn & 0x80000000) == 0)
- /* prel31 to the unwind table */
- ctrl.insn = (unsigned long *)prel31_to_addr(&idx->insn);
- else if ((idx->insn & 0xff000000) == 0x80000000)
- /* only personality routine 0 supported in the index */
- ctrl.insn = &idx->insn;
- else {
- pr_warning("unwind: Unsupported personality routine %08lx in the index at %p\n",
- idx->insn, idx);
- return -URC_FAILURE;
- }
-
- /* check the personality routine */
- if ((*ctrl.insn & 0xff000000) == 0x80000000) {
- ctrl.byte = 2;
- ctrl.entries = 1;
- } else if ((*ctrl.insn & 0xff000000) == 0x81000000) {
- ctrl.byte = 1;
- ctrl.entries = 1 + ((*ctrl.insn & 0x00ff0000) >> 16);
- } else {
- pr_warning("unwind: Unsupported personality routine %08lx at %p\n",
- *ctrl.insn, ctrl.insn);
- return -URC_FAILURE;
- }
-
- while (ctrl.entries > 0) {
- int urc = unwind_exec_insn(&ctrl);
- if (urc < 0)
- return urc;
- if (ctrl.vrs[SP] < low || ctrl.vrs[SP] >= high)
- return -URC_FAILURE;
- }
-
- if (ctrl.vrs[PC] == 0)
- ctrl.vrs[PC] = ctrl.vrs[LR];
-
- /* check for infinite loop */
- if (frame->pc == ctrl.vrs[PC])
- return -URC_FAILURE;
-
- frame->fp = ctrl.vrs[FP];
- frame->sp = ctrl.vrs[SP];
- frame->lr = ctrl.vrs[LR];
- frame->pc = ctrl.vrs[PC];
-
- return URC_OK;
-}
-
-void unwind_backtrace(struct pt_regs *regs, struct task_struct *tsk)
-{
- struct stackframe frame;
- register unsigned long current_sp asm ("sp");
-
- pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk);
-
- if (!tsk)
- tsk = current;
-
- if (regs) {
- frame.fp = regs->ARM_fp;
- frame.sp = regs->ARM_sp;
- frame.lr = regs->ARM_lr;
- /* PC might be corrupted, use LR in that case. */
- frame.pc = kernel_text_address(regs->ARM_pc)
- ? regs->ARM_pc : regs->ARM_lr;
- } else if (tsk == current) {
- frame.fp = (unsigned long)__builtin_frame_address(0);
- frame.sp = current_sp;
- frame.lr = (unsigned long)__builtin_return_address(0);
- frame.pc = (unsigned long)unwind_backtrace;
- } else {
- /* task blocked in __switch_to */
- frame.fp = thread_saved_fp(tsk);
- frame.sp = thread_saved_sp(tsk);
- /*
- * The function calling __switch_to cannot be a leaf function
- * so LR is recovered from the stack.
- */
- frame.lr = 0;
- frame.pc = thread_saved_pc(tsk);
- }
-
- while (1) {
- int urc;
- unsigned long where = frame.pc;
-
- urc = unwind_frame(&frame);
- if (urc < 0)
- break;
- dump_backtrace_entry(where, frame.pc, frame.sp - 4);
- }
-}
-
-struct unwind_table *unwind_table_add(unsigned long start, unsigned long size,
- unsigned long text_addr,
- unsigned long text_size)
-{
- unsigned long flags;
- struct unwind_table *tab = kmalloc(sizeof(*tab), GFP_KERNEL);
-
- pr_debug("%s(%08lx, %08lx, %08lx, %08lx)\n", __func__, start, size,
- text_addr, text_size);
-
- if (!tab)
- return tab;
-
- tab->start = (const struct unwind_idx *)start;
- tab->stop = (const struct unwind_idx *)(start + size);
- tab->origin = unwind_find_origin(tab->start, tab->stop);
- tab->begin_addr = text_addr;
- tab->end_addr = text_addr + text_size;
-
- spin_lock_irqsave(&unwind_lock, flags);
- list_add_tail(&tab->list, &unwind_tables);
- spin_unlock_irqrestore(&unwind_lock, flags);
-
- return tab;
-}
-
-void unwind_table_del(struct unwind_table *tab)
-{
- unsigned long flags;
-
- if (!tab)
- return;
-
- spin_lock_irqsave(&unwind_lock, flags);
- list_del(&tab->list);
- spin_unlock_irqrestore(&unwind_lock, flags);
-
- kfree(tab);
-}
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