1/* $NetBSD: rtld_start.S,v 1.7 2002/09/12 17:18:38 mycroft Exp $ */ 2 3/*- 4 * Copyright (c) 1998, 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matt Thomas and by Charles M. Hannum. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#include <machine/asm.h> 33 .text 34 .align 0 35 .globl .rtld_start 36 .type .rtld_start,%function 37.rtld_start: 38 mov r6, sp /* save the stack pointer */ 39 bic sp, sp, #7 /* align the stack pointer */ 40 sub sp, sp, #8 /* make room for obj_main & exit proc */ 41 mov r4, r0 /* save ps_strings */ 42 ldr sl, .L2 43 ldr r5, .L2+4 44 ldr r0, .L2+8 45.L1: 46 add sl, pc, sl 47 ldr r5, [sl, r5] 48 ldr r0, [sl, r0] 49 50 sub r1, sl, r5 /* relocbase */ 51 add r0, r1, r0 /* &_DYNAMIC */ 52 bl _rtld_relocate_nonplt_self 53 mov r1, sp 54 add r2, sp, #4 55 mov r0, r6 /* load the sp the kernel gave us */ 56 bl _rtld /* call the shared loader */ 57 mov r3, r0 /* save entry point */ 58 59 ldr r2, [sp, #0] /* r2 = cleanup */ 60 ldr r1, [sp, #4] /* r1 = obj_main */ 61 mov sp, r6 /* restore stack */ 62 mov r0, r4 /* restore ps_strings */ 63 mov pc, r3 /* jump to the entry point */ 64.L2: 65 .word _GLOBAL_OFFSET_TABLE_ - (.L1+8) 66 .word _GLOBAL_OFFSET_TABLE_(GOT) 67 .word _DYNAMIC(GOT) 68 69 .align 0 70 .globl _rtld_bind_start 71 .type _rtld_bind_start,%function 72/* 73 * stack[0] = RA 74 * ip = &GOT[n+3] 75 * lr = &GOT[2] 76 */ 77_rtld_bind_start: 78 stmdb sp!,{r0-r5,sl,fp} 79 80 sub r1, ip, lr /* r1 = 4 * (n + 1) */ 81 sub r1, r1, #4 /* r1 = 4 * n */ 82 add r1, r1, r1 /* r1 = 8 * n */ 83 84 ldr r0, [lr, #-4] /* get obj ptr from GOT[1] */ 85 mov r4, ip /* save GOT location */ 86 87 mov r5, sp /* Save the stack pointer */ 88 bic sp, sp, #7 /* Align the stack pointer */ 89 bl _rtld_bind /* Call the binder */ 90 mov sp, r5 /* Restore the old stack pointer */ 91 92 str r0, [r4] /* save address in GOT */ 93 mov ip, r0 /* save new address */ 94 95 ldmia sp!,{r0-r5,sl,fp,lr} /* restore the stack */ 96 mov pc, ip /* jump to the new address */ 97 98 .section .note.GNU-stack,"",%progbits 99