1/* 2 * Signal trampolines for 32 bits processes in a ppc64 kernel for 3 * use in the vDSO 4 * 5 * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp. 6 * Copyright (C) 2004 Alan Modra (amodra@au.ibm.com)), IBM Corp. 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * as published by the Free Software Foundation; either version 11 * 2 of the License, or (at your option) any later version. 12 */ 13#include <asm/processor.h> 14#include <asm/ppc_asm.h> 15#include <asm/unistd.h> 16#include <asm/vdso.h> 17 18 .text 19 20/* The nop here is a hack. The dwarf2 unwind routines subtract 1 from 21 the return address to get an address in the middle of the presumed 22 call instruction. Since we don't have a call here, we artifically 23 extend the range covered by the unwind info by adding a nop before 24 the real start. */ 25 nop 26V_FUNCTION_BEGIN(__kernel_sigtramp32) 27.Lsig_start = . - 4 28 li r0,__NR_sigreturn 29 sc 30.Lsig_end: 31V_FUNCTION_END(__kernel_sigtramp32) 32 33.Lsigrt_start: 34 nop 35V_FUNCTION_BEGIN(__kernel_sigtramp_rt32) 36 li r0,__NR_rt_sigreturn 37 sc 38.Lsigrt_end: 39V_FUNCTION_END(__kernel_sigtramp_rt32) 40 41 .section .eh_frame,"a",@progbits 42 43/* Register r1 can be found at offset 4 of a pt_regs structure. 44 A pointer to the pt_regs is stored in memory at the old sp plus PTREGS. */ 45#define cfa_save \ 46 .byte 0x0f; /* DW_CFA_def_cfa_expression */ \ 47 .uleb128 9f - 1f; /* length */ \ 481: \ 49 .byte 0x71; .sleb128 PTREGS; /* DW_OP_breg1 */ \ 50 .byte 0x06; /* DW_OP_deref */ \ 51 .byte 0x23; .uleb128 RSIZE; /* DW_OP_plus_uconst */ \ 52 .byte 0x06; /* DW_OP_deref */ \ 539: 54 55/* Register REGNO can be found at offset OFS of a pt_regs structure. 56 A pointer to the pt_regs is stored in memory at the old sp plus PTREGS. */ 57#define rsave(regno, ofs) \ 58 .byte 0x10; /* DW_CFA_expression */ \ 59 .uleb128 regno; /* regno */ \ 60 .uleb128 9f - 1f; /* length */ \ 611: \ 62 .byte 0x71; .sleb128 PTREGS; /* DW_OP_breg1 */ \ 63 .byte 0x06; /* DW_OP_deref */ \ 64 .ifne ofs; \ 65 .byte 0x23; .uleb128 ofs; /* DW_OP_plus_uconst */ \ 66 .endif; \ 679: 68 69/* If msr bit 1<<25 is set, then VMX register REGNO is at offset REGNO*16 70 of the VMX reg struct. The VMX reg struct is at offset VREGS of 71 the pt_regs struct. This macro is for REGNO == 0, and contains 72 'subroutines' that the other macros jump to. */ 73#define vsave_msr0(regno) \ 74 .byte 0x10; /* DW_CFA_expression */ \ 75 .uleb128 regno + 77; /* regno */ \ 76 .uleb128 9f - 1f; /* length */ \ 771: \ 78 .byte 0x30 + regno; /* DW_OP_lit0 */ \ 792: \ 80 .byte 0x40; /* DW_OP_lit16 */ \ 81 .byte 0x1e; /* DW_OP_mul */ \ 823: \ 83 .byte 0x71; .sleb128 PTREGS; /* DW_OP_breg1 */ \ 84 .byte 0x06; /* DW_OP_deref */ \ 85 .byte 0x12; /* DW_OP_dup */ \ 86 .byte 0x23; /* DW_OP_plus_uconst */ \ 87 .uleb128 33*RSIZE; /* msr offset */ \ 88 .byte 0x06; /* DW_OP_deref */ \ 89 .byte 0x0c; .long 1 << 25; /* DW_OP_const4u */ \ 90 .byte 0x1a; /* DW_OP_and */ \ 91 .byte 0x12; /* DW_OP_dup, ret 0 if bra taken */ \ 92 .byte 0x30; /* DW_OP_lit0 */ \ 93 .byte 0x29; /* DW_OP_eq */ \ 94 .byte 0x28; .short 0x7fff; /* DW_OP_bra to end */ \ 95 .byte 0x13; /* DW_OP_drop, pop the 0 */ \ 96 .byte 0x23; .uleb128 VREGS; /* DW_OP_plus_uconst */ \ 97 .byte 0x22; /* DW_OP_plus */ \ 98 .byte 0x2f; .short 0x7fff; /* DW_OP_skip to end */ \ 999: 100 101/* If msr bit 1<<25 is set, then VMX register REGNO is at offset REGNO*16 102 of the VMX reg struct. REGNO is 1 thru 31. */ 103#define vsave_msr1(regno) \ 104 .byte 0x10; /* DW_CFA_expression */ \ 105 .uleb128 regno + 77; /* regno */ \ 106 .uleb128 9f - 1f; /* length */ \ 1071: \ 108 .byte 0x30 + regno; /* DW_OP_lit n */ \ 109 .byte 0x2f; .short 2b - 9f; /* DW_OP_skip */ \ 1109: 111 112/* If msr bit 1<<25 is set, then VMX register REGNO is at offset OFS of 113 the VMX save block. */ 114#define vsave_msr2(regno, ofs) \ 115 .byte 0x10; /* DW_CFA_expression */ \ 116 .uleb128 regno + 77; /* regno */ \ 117 .uleb128 9f - 1f; /* length */ \ 1181: \ 119 .byte 0x0a; .short ofs; /* DW_OP_const2u */ \ 120 .byte 0x2f; .short 3b - 9f; /* DW_OP_skip */ \ 1219: 122 123/* VMX register REGNO is at offset OFS of the VMX save area. */ 124#define vsave(regno, ofs) \ 125 .byte 0x10; /* DW_CFA_expression */ \ 126 .uleb128 regno + 77; /* regno */ \ 127 .uleb128 9f - 1f; /* length */ \ 1281: \ 129 .byte 0x71; .sleb128 PTREGS; /* DW_OP_breg1 */ \ 130 .byte 0x06; /* DW_OP_deref */ \ 131 .byte 0x23; .uleb128 VREGS; /* DW_OP_plus_uconst */ \ 132 .byte 0x23; .uleb128 ofs; /* DW_OP_plus_uconst */ \ 1339: 134 135/* This is where the pt_regs pointer can be found on the stack. */ 136#define PTREGS 64+28 137 138/* Size of regs. */ 139#define RSIZE 4 140 141/* This is the offset of the VMX regs. */ 142#define VREGS 48*RSIZE+34*8 143 144/* Describe where general purpose regs are saved. */ 145#define EH_FRAME_GEN \ 146 cfa_save; \ 147 rsave ( 0, 0*RSIZE); \ 148 rsave ( 2, 2*RSIZE); \ 149 rsave ( 3, 3*RSIZE); \ 150 rsave ( 4, 4*RSIZE); \ 151 rsave ( 5, 5*RSIZE); \ 152 rsave ( 6, 6*RSIZE); \ 153 rsave ( 7, 7*RSIZE); \ 154 rsave ( 8, 8*RSIZE); \ 155 rsave ( 9, 9*RSIZE); \ 156 rsave (10, 10*RSIZE); \ 157 rsave (11, 11*RSIZE); \ 158 rsave (12, 12*RSIZE); \ 159 rsave (13, 13*RSIZE); \ 160 rsave (14, 14*RSIZE); \ 161 rsave (15, 15*RSIZE); \ 162 rsave (16, 16*RSIZE); \ 163 rsave (17, 17*RSIZE); \ 164 rsave (18, 18*RSIZE); \ 165 rsave (19, 19*RSIZE); \ 166 rsave (20, 20*RSIZE); \ 167 rsave (21, 21*RSIZE); \ 168 rsave (22, 22*RSIZE); \ 169 rsave (23, 23*RSIZE); \ 170 rsave (24, 24*RSIZE); \ 171 rsave (25, 25*RSIZE); \ 172 rsave (26, 26*RSIZE); \ 173 rsave (27, 27*RSIZE); \ 174 rsave (28, 28*RSIZE); \ 175 rsave (29, 29*RSIZE); \ 176 rsave (30, 30*RSIZE); \ 177 rsave (31, 31*RSIZE); \ 178 rsave (67, 32*RSIZE); /* ap, used as temp for nip */ \ 179 rsave (65, 36*RSIZE); /* lr */ \ 180 rsave (70, 38*RSIZE) /* cr */ 181 182/* Describe where the FP regs are saved. */ 183#define EH_FRAME_FP \ 184 rsave (32, 48*RSIZE + 0*8); \ 185 rsave (33, 48*RSIZE + 1*8); \ 186 rsave (34, 48*RSIZE + 2*8); \ 187 rsave (35, 48*RSIZE + 3*8); \ 188 rsave (36, 48*RSIZE + 4*8); \ 189 rsave (37, 48*RSIZE + 5*8); \ 190 rsave (38, 48*RSIZE + 6*8); \ 191 rsave (39, 48*RSIZE + 7*8); \ 192 rsave (40, 48*RSIZE + 8*8); \ 193 rsave (41, 48*RSIZE + 9*8); \ 194 rsave (42, 48*RSIZE + 10*8); \ 195 rsave (43, 48*RSIZE + 11*8); \ 196 rsave (44, 48*RSIZE + 12*8); \ 197 rsave (45, 48*RSIZE + 13*8); \ 198 rsave (46, 48*RSIZE + 14*8); \ 199 rsave (47, 48*RSIZE + 15*8); \ 200 rsave (48, 48*RSIZE + 16*8); \ 201 rsave (49, 48*RSIZE + 17*8); \ 202 rsave (50, 48*RSIZE + 18*8); \ 203 rsave (51, 48*RSIZE + 19*8); \ 204 rsave (52, 48*RSIZE + 20*8); \ 205 rsave (53, 48*RSIZE + 21*8); \ 206 rsave (54, 48*RSIZE + 22*8); \ 207 rsave (55, 48*RSIZE + 23*8); \ 208 rsave (56, 48*RSIZE + 24*8); \ 209 rsave (57, 48*RSIZE + 25*8); \ 210 rsave (58, 48*RSIZE + 26*8); \ 211 rsave (59, 48*RSIZE + 27*8); \ 212 rsave (60, 48*RSIZE + 28*8); \ 213 rsave (61, 48*RSIZE + 29*8); \ 214 rsave (62, 48*RSIZE + 30*8); \ 215 rsave (63, 48*RSIZE + 31*8) 216 217/* Describe where the VMX regs are saved. */ 218#ifdef CONFIG_ALTIVEC 219#define EH_FRAME_VMX \ 220 vsave_msr0 ( 0); \ 221 vsave_msr1 ( 1); \ 222 vsave_msr1 ( 2); \ 223 vsave_msr1 ( 3); \ 224 vsave_msr1 ( 4); \ 225 vsave_msr1 ( 5); \ 226 vsave_msr1 ( 6); \ 227 vsave_msr1 ( 7); \ 228 vsave_msr1 ( 8); \ 229 vsave_msr1 ( 9); \ 230 vsave_msr1 (10); \ 231 vsave_msr1 (11); \ 232 vsave_msr1 (12); \ 233 vsave_msr1 (13); \ 234 vsave_msr1 (14); \ 235 vsave_msr1 (15); \ 236 vsave_msr1 (16); \ 237 vsave_msr1 (17); \ 238 vsave_msr1 (18); \ 239 vsave_msr1 (19); \ 240 vsave_msr1 (20); \ 241 vsave_msr1 (21); \ 242 vsave_msr1 (22); \ 243 vsave_msr1 (23); \ 244 vsave_msr1 (24); \ 245 vsave_msr1 (25); \ 246 vsave_msr1 (26); \ 247 vsave_msr1 (27); \ 248 vsave_msr1 (28); \ 249 vsave_msr1 (29); \ 250 vsave_msr1 (30); \ 251 vsave_msr1 (31); \ 252 vsave_msr2 (33, 32*16+12); \ 253 vsave (32, 32*16) 254#else 255#define EH_FRAME_VMX 256#endif 257 258.Lcie: 259 .long .Lcie_end - .Lcie_start 260.Lcie_start: 261 .long 0 /* CIE ID */ 262 .byte 1 /* Version number */ 263 .string "zRS" /* NUL-terminated augmentation string */ 264 .uleb128 4 /* Code alignment factor */ 265 .sleb128 -4 /* Data alignment factor */ 266 .byte 67 /* Return address register column, ap */ 267 .uleb128 1 /* Augmentation value length */ 268 .byte 0x1b /* DW_EH_PE_pcrel | DW_EH_PE_sdata4. */ 269 .byte 0x0c,1,0 /* DW_CFA_def_cfa: r1 ofs 0 */ 270 .balign 4 271.Lcie_end: 272 273 .long .Lfde0_end - .Lfde0_start 274.Lfde0_start: 275 .long .Lfde0_start - .Lcie /* CIE pointer. */ 276 .long .Lsig_start - . /* PC start, length */ 277 .long .Lsig_end - .Lsig_start 278 .uleb128 0 /* Augmentation */ 279 EH_FRAME_GEN 280 EH_FRAME_FP 281 EH_FRAME_VMX 282 .balign 4 283.Lfde0_end: 284 285/* We have a different stack layout for rt_sigreturn. */ 286#undef PTREGS 287#define PTREGS 64+16+128+20+28 288 289 .long .Lfde1_end - .Lfde1_start 290.Lfde1_start: 291 .long .Lfde1_start - .Lcie /* CIE pointer. */ 292 .long .Lsigrt_start - . /* PC start, length */ 293 .long .Lsigrt_end - .Lsigrt_start 294 .uleb128 0 /* Augmentation */ 295 EH_FRAME_GEN 296 EH_FRAME_FP 297 EH_FRAME_VMX 298 .balign 4 299.Lfde1_end: 300