1/* $OpenBSD: ldasm.S,v 1.29 2012/10/24 03:26:56 guenther Exp $ */ 2/* $NetBSD: rtld_start.S,v 1.5 2001/08/14 22:17:48 eeh Exp $ */ 3 4/* 5 * Copyright (c) 2001 Jason L. Wright (jason@thought.net) 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 21 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 23 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 25 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 26 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 * POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30/*- 31 * Copyright (c) 2000 Eduardo Horvath. 32 * Copyright (c) 1999 The NetBSD Foundation, Inc. 33 * All rights reserved. 34 * 35 * This code is derived from software contributed to The NetBSD Foundation 36 * by Christos Zoulas and Paul Kranenburg. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the NetBSD 49 * Foundation, Inc. and its contributors. 50 * 4. Neither the name of The NetBSD Foundation nor the names of its 51 * contributors may be used to endorse or promote products derived 52 * from this software without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 55 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 56 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 57 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 58 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 59 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 60 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 61 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 62 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 63 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 64 * POSSIBILITY OF SUCH DAMAGE. 65 */ 66 67#include <sys/syscall.h> 68#include <machine/trap.h> 69#include <machine/asm.h> 70#define _LOCORE 71#include <machine/frame.h> 72 73/* 74 * ELF: 75 * On startup the stack should contain 16 extended word register save 76 * area, followed by the arg count, etc. 77 * 78 * _rtld() expects the stack pointer to point to two longwords for argument 79 * return followed by argc, etc. We need to create a pointer to 80 * &argc + 16 and pass that in. The return args will be in those 81 * locations. 82 */ 83 84/* Offset of ARGC from bottom of stack */ 85#define ARGC CC64FSZ 86/* XXX - DL_DATA_SIZE should be (9*8), but I can't think right now. */ 87#define DL_DATA_SIZE (16*8) 88 89 .section ".text" 90 .align 16 91 .register %g2,#scratch 92 93_ENTRY(_dl_start) 94 sub %g0, %g0, %fp ! clear frame 95 sub %sp, 48 + DL_DATA_SIZE, %sp ! make room for dl_data 96 add %sp, BIAS + ARGC, %l3 97 98 add %l3, DL_DATA_SIZE, %o0 99 mov %o0, %l0 100 101 /* 102 * need to figure out where _DYNAMIC is located, newer binutils 103 * does not fill in GOT to read _DYNAMIC before relocation. 104 */ 105 call 0f 106 nop 107 call _DYNAMIC+8 ! not executed (no delay needed) 1080: ld [%o7+8], %o2 ! load stub call instruction 109 sll %o2, 2, %o2 ! extract PC offset 110 sra %o2, 0, %o2 ! sign-extend 111 112 add %o2, %o7, %o2 ! real &_DYNAMIC 113 114 call _dl_boot_bind ! _dl_boot_bind(sp,dl_data,dynamicp) 115 mov %l3, %o1 116 117 mov %l3, %o3 118 ldx [%l0], %l3 ! argc = *sp 119 sllx %l3, 3, %l3 ! argc *= sizeof(long) 120 addx %l0, 8, %o0 ! argv = [sp + argc] 121 addx %l0, 16, %o1 ! envp = sp + 16 + 122 addx %o1, %l3, %o1 ! + argc 123 124 addx %o3, (7*8), %l2 125 ldx [%l2], %o2 ! loff = dl_data[AUX_base]; 126 127 call _dl_boot ! _dl_boot(argv,envp,loff,dl_data) 128 nop 129 130 add %sp, 48 + DL_DATA_SIZE, %sp ! restore stack 131 132 jmp %o0 133 clr %g1 ! XXX don't register with atexit 134 135 /* 136 * We have two separate entry points to the runtime linker. 137 * I'm implementing this following the SPARC v9 ABI spec. 138 * 139 * _dl_bind_start_0(x, y) is called from .PLT0, and is used for 140 * PLT entries above 32768. 141 * 142 * _dl_bind_start_1(x, y) is called from .PLT1, and is used for 143 * PLT entries below 32768. 144 * 145 * The first two entries of PLT2 contain the xword object pointer. 146 * 147 * These routines are called with two longword arguments, 148 * x and y. To calculate the address of the entry, 149 * _dl_bind_start_1(x, y) does: 150 * 151 * n = x >> 15; 152 * 153 * and _dl_bind_start_0(x, y) does: 154 * 155 * i = x - y + 8 - 32768*32; 156 * n = 32768 + (i/5120)*160 + (i%5120)/24; 157 * 158 * Neither routine needs to issue a save since it's already been 159 * done in the PLT entry. 160 */ 161 162 /* NOTE: _dl_bind_start_0 is untested. Hence the debug stuff */ 163 164_ENTRY(_dl_bind_start_0) # (x, y) 165 sethi %hi(32768*32-8), %l1 166 sub %o0, %o1, %l0 /* x - y */ 167 or %l1, %lo(32768*32-8), %l1 168 sub %l0, %l1, %l0 /* x - y + 8 - 32768*32 */ 169 170 sethi %hi(5120), %l1 171 sdivx %l0, %l1, %l1 /* Calculate i/5120 */ 172 ldx [%o1 + (10*4)], %o0 /* Load object pointer from PLT2 */ 173 sllx %l1, 2, %l2 174 add %l1, %l2, %l2 175 sllx %l2, 10, %l2 176 sub %l0, %l2, %l2 /* And i%5120 */ 177 178 /* Let the division churn for a bit. */ 179 sdivx %l2, 24, %l4 /* (i%5120)/24 */ 180 181 /* 160 is (32 * 5) or (32 * (4 + 1)) */ 182 sllx %l1, 2, %l3 /* 4 * (i/5120) */ 183 add %l1, %l3, %l3 /* 5 * (i/5120) */ 184 sllx %l3, 5, %l3 /* 32 * 5 * (i/5120) */ 185 186 sethi %hi(32768), %l6 187 add %l3, %l4, %l5 /* %l5 = (i/5120)*160 + (i%5120)/24; */ 188 add %l5, %l6, %l5 189 190 call _dl_bind /* Call _dl_bind(obj, offset) */ 191 mov %l5, %o1 192 193 jmp %o0 /* return value == function address */ 194 restore /* Dump our stack frame */ 195 196_ENTRY(_dl_bind_start_1) # (x, y) 197 srax %o0, 15, %o2 /* %o0 is the index to our PLT slot */ 198 199 ldx [%o1 + 8], %o0 /* The object pointer is at [%o1 + 8] */ 200 201 call _dl_bind /* Call _dl_bind(obj, offset) */ 202 mov %o2, %o1 203 204 jmp %o0 /* return value == function address */ 205 restore /* Dump our stack frame */ 206 207_ENTRY(_dl_close) 208 mov SYS_close | SYSCALL_G2RFLAG, %g1 ! call sys_close 209 add %o7, 8, %g2 ! just return on success 210 t ST_SYSCALL ! off to wonderland 211 retl 212 sub %g0, %o0, %o0 ! error: result = -errno 213 214_ENTRY(_dl_exit) 215 mov SYS_exit | SYSCALL_G2RFLAG, %g1 ! call sys_exit 216 add %o7, 8, %g2 ! just return on success 217 t ST_SYSCALL ! off to wonderland 218 retl 219 sub %g0, %o0, %o0 ! error: result = -errno 220 221_ENTRY(_dl_issetugid) 222 mov SYS_issetugid | SYSCALL_G2RFLAG, %g1 ! call sys_issetugid 223 add %o7, 8, %g2 ! just return on success 224 t ST_SYSCALL ! off to wonderland 225 retl 226 sub %g0, %o0, %o0 ! error: result = -errno 227 228_ENTRY(_dl__syscall) 229 mov SYS___syscall | SYSCALL_G2RFLAG, %g1 ! call sys___syscall 230 add %o7, 8, %g2 ! just return on success 231 t ST_SYSCALL ! off to wonderland 232 retl 233 sub %g0, %o0, %o0 ! error: result = -errno 234 235_ENTRY(_dl_munmap) 236 mov SYS_munmap | SYSCALL_G2RFLAG, %g1 ! calling sys_munmap 237 add %o7, 8, %g2 ! just return on success 238 t ST_SYSCALL ! off to wonderland 239 retl 240 sub %g0, %o0, %o0 ! error: result = -errno 241 242_ENTRY(_dl_mprotect) 243 mov SYS_mprotect | SYSCALL_G2RFLAG, %g1 ! calling sys_mprotect 244 add %o7, 8, %g2 ! just return on success 245 t ST_SYSCALL ! off to wonderland 246 retl 247 sub %g0, %o0, %o0 ! error: result = -errno 248 249_ENTRY(_dl_open) 250 mov SYS_open | SYSCALL_G2RFLAG, %g1 ! calling sys_open 251 add %o7, 8, %g2 ! just return on success 252 t ST_SYSCALL ! off to wonderland 253 retl 254 sub %g0, %o0, %o0 ! error: result = -errno 255 256_ENTRY(_dl_read) 257 mov SYS_read | SYSCALL_G2RFLAG, %g1 ! calling sys_read 258 add %o7, 8, %g2 ! just return on success 259 t ST_SYSCALL ! off to wonderland 260 retl 261 sub %g0, %o0, %o0 ! error: result = -errno 262 263_ENTRY(_dl_write) 264 mov SYS_write | SYSCALL_G2RFLAG, %g1 ! calling sys_write 265 add %o7, 8, %g2 ! just return on success 266 t ST_SYSCALL ! off to wonderland 267 retl 268 sub %g0, %o0, %o0 ! error: result = -errno 269 270_ENTRY(_dl_fstat) 271 mov SYS_fstat | SYSCALL_G2RFLAG, %g1 ! call sys_fstat 272 add %o7, 8, %g2 ! just return on success 273 t ST_SYSCALL ! off to wonderland 274 retl 275 sub %g0, %o0, %o0 ! error: result = -errno 276 277_ENTRY(_dl_fcntl) 278 mov SYS_fcntl | SYSCALL_G2RFLAG, %g1 ! call sys_fcntl 279 add %o7, 8, %g2 ! just return on success 280 t ST_SYSCALL ! off to wonderland 281 retl 282 sub %g0, %o0, %o0 ! error: result = -errno 283 284_ENTRY(_dl_getdirentries) 285 mov SYS_getdirentries | SYSCALL_G2RFLAG, %g1 ! call sys_getdirentries 286 add %o7, 8, %g2 ! just return on success 287 t ST_SYSCALL ! off to wonderland 288 retl 289 sub %g0, %o0, %o0 ! error: result = -errno 290 291 /* _dl_sigprocmask does not support NULL new mask */ 292_ENTRY(_dl_sigprocmask) 293 ld [%o1], %o1 ! indirect for new mask 294 mov SYS_sigprocmask, %g1 ! call sys_sigprocmask 295 t ST_SYSCALL ! off to wonderland 296 ! what about errors? 297 cmp %o2, 0 298 bne,a 1f ! if oset != NULL 299 st %o0, [%o2] ! *oset = oldmask 3001: 301 retl 302 clr %o0 303 304_ENTRY(_dl_sysctl) 305 mov SYS___sysctl | SYSCALL_G2RFLAG, %g1 ! call sys___sysctl 306 add %o7, 8, %g2 ! just return on success 307 t ST_SYSCALL ! off to wonderland 308 retl 309 sub %g0, %o0, %o0 ! error: result = -errno 310 311_ENTRY(_dl_gettimeofday) 312 mov SYS_gettimeofday | SYSCALL_G2RFLAG, %g1 ! calling sys_gettimeofday 313 add %o7, 8, %g2 ! just return on success 314 t ST_SYSCALL ! off to wonderland 315 retl 316 sub %g0, %o0, %o0 ! error: result = -errno 317 318