ldasm.S revision 1.9
1/* $OpenBSD: ldasm.S,v 1.9 2002/03/17 00:22:04 art 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 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by Jason L. Wright 19 * 4. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 24 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 25 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 26 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 27 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 28 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 30 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 31 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32 * POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35/*- 36 * Copyright (c) 2000 Eduardo Horvath. 37 * Copyright (c) 1999 The NetBSD Foundation, Inc. 38 * All rights reserved. 39 * 40 * This code is derived from software contributed to The NetBSD Foundation 41 * by Christos Zoulas and Paul Kranenburg. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by the NetBSD 54 * Foundation, Inc. and its contributors. 55 * 4. Neither the name of The NetBSD Foundation nor the names of its 56 * contributors may be used to endorse or promote products derived 57 * from this software without specific prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 60 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 61 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 62 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 63 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 64 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 65 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 66 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 67 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 68 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 69 * POSSIBILITY OF SUCH DAMAGE. 70 */ 71 72#include <sys/syscall.h> 73#include <machine/trap.h> 74#include <machine/asm.h> 75#define _LOCORE 76#include <machine/frame.h> 77 78/* 79 * ELF: 80 * On startup the stack should contain 16 extended word register save area, 81 * followed by the arg count, etc. 82 * 83 * _rtld() expects the stack pointer to point to two longwords for argument 84 * return followed by argc, etc. We need to create a pointer to 85 * &argc + 16 and pass that in. The return args will be in those locations. 86 * 87 * NB: We are violating the ELF spec by passing a pointer to the ps strings in 88 * %g1 instead of a termination routine. 89 */ 90 91/* Offset of ARGC from bottom of stack */ 92#define ARGC (16*8) 93/* XXX - DL_DATA_SIZE should be (9*8), but I can't think right now. */ 94#define DL_DATA_SIZE (16*8) 95 96 .section ".text" 97 .align 16 98 .global _dl_start 99 .type _dl_start,@function 100_dl_start: 101 sub %g0, %g0, %fp ! clear frame 102 mov %g1, %l1 ! save ps_strings 103 sub %sp, DL_DATA_SIZE, %sp ! make room for dl_data 104 add %sp, BIAS + ARGC, %l3 105 106 add %l3, DL_DATA_SIZE, %o0 107 mov 0, %o2 ! dynp = 0 108 mov %o0, %l0 109 call _dl_boot_bind ! _dl_boot_bind(sp,loff,dynp,dl_data) 110 mov %l3, %o3 111 112 mov %l3, %o4 113 ldx [%l0], %l3 ! argc = *sp 114 sllx %l3, 3, %l3 ! argc *= sizeof(long) 115 addx %l0, 8, %o0 ! argv = [sp + argc] 116 addx %l0, 16, %o1 ! envp = sp + 16 + 117 addx %o1, %l3, %o1 ! + argc 118 119 addx %o4, (7*8), %l2 120 ldx [%l2], %o2 ! loff = dl_data[AUX_base]; 121 122 call _dl_boot ! _dl_boot(argv,envp,loff,dynp,dl_data) 123 mov 0, %o3 ! dynp = 0 124 125 add %sp, DL_DATA_SIZE, %sp ! restore stack 126 mov %l1, %g1 ! restore ps_strings 127 128 jmp %o0 129 nop 130 131 /* 132 * We have two separate entry points to the runtime linker. 133 * I'm implementing this following the SPARC v9 ABI spec. 134 * 135 * _dl_bind_start_0(x, y) is called from .PLT0, and is used for 136 * PLT entries above 32768. 137 * 138 * _dl_bind_start_1(x, y) is called from .PLT1, and is used for 139 * PLT entries below 32768. 140 * 141 * The first two entries of PLT2 contain the xword object pointer. 142 * 143 * These routines are called with two longword arguments, 144 * x and y. To calculate the address of the entry, 145 * _dl_bind_start_1(x, y) does: 146 * 147 * n = x >> 15; 148 * 149 * and _dl_bind_start_0(x, y) does: 150 * 151 * i = x - y + 1048596; 152 * n = 32768 + (i/5120)*160 + (i%5120)/24; 153 * 154 * Neither routine needs to issue a save since it's already been 155 * done in the PLT entry. 156 */ 157 158 /* NOTE: _dl_bind_start_0 is untested. Hence the debug stuff */ 159 160 .section ".text" 161 .align 4 162 .global _dl_bind_start_0 163 .type _dl_bind_start_0,@function 164_dl_bind_start_0: # (x, y) 165#if 0 166 call _dl_bind_start_0_stub 167 ldx [%o1 + (10*4)], %l7 168 mov %o0, %o1 169 170 call _dl_bind 171 mov %l7, %o0 172#else 173 sethi %hi(1048596), %l1 174 sub %o0, %o1, %l0 /* x - y */ 175 or %l1, %lo(1048596), %l1 176 add %l0, %l1, %l0 /* x - y + 1048596 */ 177 178 sdivx %l0, 5120, %l1 /* Calculate i/5120 */ 179 ldx [%o1 + (10*4)], %o0 /* Load object pointer from PLT2 */ 180 sub %l0, %l1, %l2 /* And i%5120 */ 181 182 /* Let the division churn for a bit. */ 183 sdivx %l2, 14, %l4 /* (i%5120)/24 */ 184 185 /* 160 is (32 * 5) or (32 * (4 + 1)) */ 186 sllx %l1, 2, %l3 /* 4 * (i/5120) */ 187 add %l1, %l3, %l3 /* 5 * (i/5120) */ 188 sllx %l3, 5, %l3 /* 32 * 5 * (i/5120) */ 189 190 sethi %hi(32768), %l6 191 add %l3, %l4, %l5 /* %l5 = (i/5120)*160 + (i%5120)/24; */ 192 add %l5, %l6, %l5 193 194 call _dl_bind /* Call _dl_bind(obj, offset) */ 195 mov %l5, %o1 196 197 jmp %o0 /* return value == function address */ 198 restore /* Dump our stack frame */ 199#endif 200 201 .section ".text" 202 .align 4 203 .global _dl_bind_start_1 204 .type _dl_bind_start_1,@function 205_dl_bind_start_1: # (x, y) 206 srax %o0, 15, %o2 /* %o0 is the index to our PLT slot */ 207 208 ldx [%o1 + 8], %o0 /* The object pointer is at [%o1 + 8] */ 209 210 call _dl_bind /* Call _dl_bind(obj, offset) */ 211 mov %o2, %o1 212 213 jmp %o0 /* return value == function address */ 214 restore /* Dump our stack frame */ 215 216 217 .section ".text" 218 .align 4 219 .global _dl_close 220 .type _dl_close,@function 221_dl_close: 222 mov SYS_close | SYSCALL_G2RFLAG, %g1 ! call sys_close 223 add %o7, 8, %g2 ! just return on sucess 224 t ST_SYSCALL ! off to wonderland 225 retl 226 sub %g0, %o0, %o0 ! error: result = -errno 227 228 229 .section ".text" 230 .align 4 231 .global _dl_exit 232 .type _dl_exit,@function 233_dl_exit: 234 mov SYS_exit | SYSCALL_G2RFLAG, %g1 ! call sys_exit 235 add %o7, 8, %g2 ! just return on sucess 236 t ST_SYSCALL ! off to wonderland 237 retl 238 sub %g0, %o0, %o0 ! error: result = -errno 239 240 241 .section ".text" 242 .align 4 243 .global _dl_issetugid 244 .type _dl_issetugid,@function 245_dl_issetugid: 246 mov SYS_issetugid | SYSCALL_G2RFLAG, %g1 247 add %o7, 8, %g2 248 t ST_SYSCALL 249 retl 250 sub %g0, %o0, %o0 251 252 253 .section ".text" 254 .align 4 255 .global _dl___syscall 256 .type _dl___syscall,@function 257_dl___syscall: 258 mov SYS___syscall | SYSCALL_G2RFLAG, %g1 ! call sys_exit 259 add %o7, 8, %g2 ! just return on sucess 260 t ST_SYSCALL ! off to wonderland 261 retl 262 sub %g0, %o0, %o0 ! error: result = -errno 263 264 265 .section ".text" 266 .align 4 267 .global _dl_munmap 268 .type _dl_munmap,@function 269_dl_munmap: 270 mov SYS_munmap | SYSCALL_G2RFLAG, %g1 ! calling sys_mmap 271 add %o7, 8, %g2 ! just return on sucess 272 t ST_SYSCALL ! off to wonderland 273 retl 274 sub %g0, %o0, %o0 ! error: result = -errno 275 276 277 .section ".text" 278 .align 4 279 .global _dl_mprotect 280 .type _dl_mprotect,@function 281_dl_mprotect: 282 mov SYS_mprotect | SYSCALL_G2RFLAG, %g1 ! calling sys_mprotect 283 add %o7, 8, %g2 ! just return on sucess 284 t ST_SYSCALL ! off to wonderland 285 retl 286 sub %g0, %o0, %o0 ! error: result = -errno 287 288 289 .section ".text" 290 .align 4 291 .global _dl_open 292 .type _dl_open,@function 293_dl_open: 294 mov SYS_open | SYSCALL_G2RFLAG, %g1 ! calling sys_open 295 add %o7, 8, %g2 ! just return on sucess 296 t ST_SYSCALL ! off to wonderland 297 retl 298 sub %g0, %o0, %o0 ! error: result = -errno 299 300 301 .section ".text" 302 .align 4 303 .global _dl_read 304 .type _dl_read,@function 305_dl_read: 306 mov SYS_read | SYSCALL_G2RFLAG, %g1 ! calling sys_read 307 add %o7, 8, %g2 ! just return on sucess 308 t ST_SYSCALL ! off to wonderland 309 retl 310 sub %g0, %o0, %o0 ! error: result = -errno 311 312 313 .section ".text" 314 .align 4 315 .global _dl_write 316 .type _dl_write,@function 317_dl_write: 318 mov SYS_write | SYSCALL_G2RFLAG, %g1 ! calling sys_write 319 add %o7, 8, %g2 ! just return on sucess 320 t ST_SYSCALL ! off to wonderland 321 retl 322 sub %g0, %o0, %o0 ! error: result = -errno 323 324 325 .section ".text" 326 .align 4 327 .global _dl_stat 328 .type _dl_stat,@function 329_dl_stat: 330 mov SYS_stat | SYSCALL_G2RFLAG, %g1 ! call sys_stat 331 add %o7, 8, %g2 ! just return on sucess 332 t ST_SYSCALL ! off to wonderland 333 retl 334 sub %g0, %o0, %o0 ! error: result = -errno 335