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/* $OpenBSD: md_init.h,v 1.5 2015/09/09 09:41:42 kettenis Exp $ */
/*-
* Copyright (c) 2001 Ross Harvey
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#define MD_SECT_CALL_FUNC(section, func) \
__asm (".section "#section", \"ax\"\n" \
" bl " #func "\n" \
" .previous")
#define MD_SECTION_PROLOGUE(sect, entry_pt) \
__asm ( \
".section "#sect",\"ax\",@progbits \n" \
" .globl " #entry_pt " \n" \
" .type " #entry_pt ",@function \n" \
" .align 4 \n" \
#entry_pt": \n" \
" stwu %r1,-16(%r1) \n" \
" mflr %r0 \n" \
" stw %r0,12(%r1) \n" \
" /* fall thru */ \n" \
" .previous")
#define MD_SECTION_EPILOGUE(sect) \
__asm ( \
".section "#sect",\"ax\",@progbits \n" \
" lwz %r0,12(%r1) \n" \
" mtlr %r0 \n" \
" addi %r1,%r1,16 \n" \
" blr \n" \
" .previous")
#include <sys/syscall.h> /* for SYS_mprotect */
#define STR(x) __STRING(x)
#define MD_CRT0_START \
__asm( \
" .text \n" \
" .section \".text\" \n" \
" .align 2 \n" \
" .globl _start \n" \
" .type _start, @function \n" \
" .globl __start \n" \
" .type __start, @function \n" \
"_start: \n" \
"__start: \n" \
" # put cleanup in r6 instead of r7 \n" \
" mr %r6, %r7 \n" \
" b ___start \n" \
)
#define MD_RCRT0_START \
__asm( \
" .text \n" \
" .section \".text\" \n" \
" .align 2 \n" \
" .globl _start \n" \
" .type _start, @function \n" \
" .globl __start \n" \
" .type __start, @function \n" \
"_start: \n" \
"__start: \n" \
" mr %r19, %r1 # save stack in r19 \n" \
" stwu 1, (-16 -((9+3)*4))(%r1) # allocate dl_data \n" \
" \n" \
" # move argument registers to saved registers for startup flush \n" \
" mr %r20, %r3 # argc \n" \
" mr %r21, %r4 # argv \n" \
" mr %r22, %r5 # envp \n" \
" mflr %r27 /* save off old link register */ \n" \
" stw %r27, 4(%r19) # save in normal location \n" \
" bl 1f \n" \
" # this instruction never gets executed but can be used \n" \
" # to find the virtual address where the page is loaded. \n" \
" bl _GLOBAL_OFFSET_TABLE_@local-4 \n" \
" bl _DYNAMIC@local \n" \
"1: \n" \
" mflr %r6 # this stores where we are (+4) \n" \
" lwz %r18, 0(%r6) # load the instruction at offset_sym \n" \
" # it contains an offset to the location \n" \
" # of the GOT. \n" \
" \n" \
" rlwinm %r18,%r18,0,8,30 # mask off offset portion of the instr. \n" \
" \n" \
" /* \n" \
" * these adds effectively calculate the value the \n" \
" * bl _GLOBAL_OFFSET_TABLE_@local-4 \n" \
" * operation that would be below would calculate. \n" \
" */ \n" \
" add %r28, %r18, %r6 \n" \
" \n" \
" /* mprotect GOT-4 for correct execution of blrl instruction */ \n" \
" li %r0, " STR(SYS_mprotect) " \n" \
" mr %r3, %r28 \n" \
" li %r4, 4 \n" \
" li %r5, 7 /* (PROT_READ|PROT_WRITE|PROT_EXEC) */ \n" \
" sc \n" \
" \n" \
" li %r0, 0 \n" \
" # flush the blrl instruction out of the data cache \n" \
" dcbf %r6, %r18 \n" \
" sync \n" \
" isync \n" \
" # make certain that the got table addr is not in the icache \n" \
" icbi %r6, %r18 \n" \
" sync \n" \
" isync \n" \
" \n" \
" /* This calculates the address of _DYNAMIC the same way \n" \
" * that the GLOBAL_OFFSET_TABLE was calculated. \n" \
" */ \n" \
" lwz %r18, 4(%r6) \n" \
" rlwinm %r18,%r18,0,8,30 # mask off offset portion of the instr. \n" \
" add %r8, %r18, %r6 # address of _DYNAMIC (arg6 for _dl_boot) \n" \
" addi %r18, %r8, 4 # correction. \n" \
" lwz %r4, 4(%r28) # load addr of _DYNAMIC according to got. \n" \
" sub %r4, %r18, %r4 # determine load offset \n" \
" \n" \
" subi %r3, %r21, 4 # Get stack pointer (arg0 for _dl_boot). \n" \
" addi %r4, %r1, 8 # dl_data \n" \
" mr %r5, %r18 # dynamicp \n" \
" \n" \
" bl _dl_boot_bind@local \n" \
" \n" \
" mtlr %r27 \n" \
" # move argument registers back from saved registers \n" \
" mr %r3, %r20 \n" \
" mr %r4, %r21 \n" \
" mr %r5, %r22 \n" \
" li %r6, 0 \n" \
" b ___start \n" \
" \n" \
" .text \n" \
" .align 2 \n" \
" .globl _dl_exit \n" \
" .type _dl_exit, @function \n" \
"_dl_exit: \n" \
" li %r0, " STR(SYS_exit) " \n" \
" sc \n" \
" blr \n" \
" \n" \
" .text \n" \
" .align 2 \n" \
" .globl _dl_printf \n" \
" .type _dl_printf, @function \n" \
"_dl_printf: \n" \
" blr \n" \
)
#include <sys/syscall.h>
#define MD_DISABLE_KBIND \
__asm volatile("li %%r3, 0; li %%r0, %0; sc" : \
: "i" (SYS_kbind) : "r0", "r3", "r4", "cc")
|
