/* * Signal trampolines for 32 bits processes in a ppc64 kernel for * use in the vDSO * * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp. * Copyright (C) 2004 Alan Modra (amodra@au.ibm.com)), IBM Corp. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include <linux/config.h> #include <asm/processor.h> #include <asm/ppc_asm.h> #include <asm/unistd.h> #include <asm/vdso.h> .text /* The nop here is a hack. The dwarf2 unwind routines subtract 1 from the return address to get an address in the middle of the presumed call instruction. Since we don't have a call here, we artifically extend the range covered by the unwind info by adding a nop before the real start. */ nop V_FUNCTION_BEGIN(__kernel_sigtramp32) .Lsig_start = . - 4 li r0,__NR_sigreturn sc .Lsig_end: V_FUNCTION_END(__kernel_sigtramp32) .Lsigrt_start: nop V_FUNCTION_BEGIN(__kernel_sigtramp_rt32) li r0,__NR_rt_sigreturn sc .Lsigrt_end: V_FUNCTION_END(__kernel_sigtramp_rt32) .section .eh_frame,"a",@progbits /* Register r1 can be found at offset 4 of a pt_regs structure. A pointer to the pt_regs is stored in memory at the old sp plus PTREGS. */ #define cfa_save \ .byte 0x0f; /* DW_CFA_def_cfa_expression */ \ .uleb128 9f - 1f; /* length */ \ 1: \ .byte 0x71; .sleb128 PTREGS; /* DW_OP_breg1 */ \ .byte 0x06; /* DW_OP_deref */ \ .byte 0x23; .uleb128 RSIZE; /* DW_OP_plus_uconst */ \ .byte 0x06; /* DW_OP_deref */ \ 9: /* Register REGNO can be found at offset OFS of a pt_regs structure. A pointer to the pt_regs is stored in memory at the old sp plus PTREGS. */ #define rsave(regno, ofs) \ .byte 0x10; /* DW_CFA_expression */ \ .uleb128 regno; /* regno */ \ .uleb128 9f - 1f; /* length */ \ 1: \ .byte 0x71; .sleb128 PTREGS; /* DW_OP_breg1 */ \ .byte 0x06; /* DW_OP_deref */ \ .ifne ofs; \ .byte 0x23; .uleb128 ofs; /* DW_OP_plus_uconst */ \ .endif; \ 9: /* If msr bit 1<<25 is set, then VMX register REGNO is at offset REGNO*16 of the VMX reg struct. The VMX reg struct is at offset VREGS of the pt_regs struct. This macro is for REGNO == 0, and contains 'subroutines' that the other macros jump to. */ #define vsave_msr0(regno) \ .byte 0x10; /* DW_CFA_expression */ \ .uleb128 regno + 77; /* regno */ \ .uleb128 9f - 1f; /* length */ \ 1: \ .byte 0x30 + regno; /* DW_OP_lit0 */ \ 2: \ .byte 0x40; /* DW_OP_lit16 */ \ .byte 0x1e; /* DW_OP_mul */ \ 3: \ .byte 0x71; .sleb128 PTREGS; /* DW_OP_breg1 */ \ .byte 0x06; /* DW_OP_deref */ \ .byte 0x12; /* DW_OP_dup */ \ .byte 0x23; /* DW_OP_plus_uconst */ \ .uleb128 33*RSIZE; /* msr offset */ \ .byte 0x06; /* DW_OP_deref */ \ .byte 0x0c; .long 1 << 25; /* DW_OP_const4u */ \ .byte 0x1a; /* DW_OP_and */ \ .byte 0x12; /* DW_OP_dup, ret 0 if bra taken */ \ .byte 0x30; /* DW_OP_lit0 */ \ .byte 0x29; /* DW_OP_eq */ \ .byte 0x28; .short 0x7fff; /* DW_OP_bra to end */ \ .byte 0x13; /* DW_OP_drop, pop the 0 */ \ .byte 0x23; .uleb128 VREGS; /* DW_OP_plus_uconst */ \ .byte 0x22; /* DW_OP_plus */ \ .byte 0x2f; .short 0x7fff; /* DW_OP_skip to end */ \ 9: /* If msr bit 1<<25 is set, then VMX register REGNO is at offset REGNO*16 of the VMX reg struct. REGNO is 1 thru 31. */ #define vsave_msr1(regno) \ .byte 0x10; /* DW_CFA_expression */ \ .uleb128 regno + 77; /* regno */ \ .uleb128 9f - 1f; /* length */ \ 1: \ .byte 0x30 + regno; /* DW_OP_lit n */ \ .byte 0x2f; .short 2b - 9f; /* DW_OP_skip */ \ 9: /* If msr bit 1<<25 is set, then VMX register REGNO is at offset OFS of the VMX save block. */ #define vsave_msr2(regno, ofs) \ .byte 0x10; /* DW_CFA_expression */ \ .uleb128 regno + 77; /* regno */ \ .uleb128 9f - 1f; /* length */ \ 1: \ .byte 0x0a; .short ofs; /* DW_OP_const2u */ \ .byte 0x2f; .short 3b - 9f; /* DW_OP_skip */ \ 9: /* VMX register REGNO is at offset OFS of the VMX save area. */ #define vsave(regno, ofs) \ .byte 0x10; /* DW_CFA_expression */ \ .uleb128 regno + 77; /* regno */ \ .uleb128 9f - 1f; /* length */ \ 1: \ .byte 0x71; .sleb128 PTREGS; /* DW_OP_breg1 */ \ .byte 0x06; /* DW_OP_deref */ \ .byte 0x23; .uleb128 VREGS; /* DW_OP_plus_uconst */ \ .byte 0x23; .uleb128 ofs; /* DW_OP_plus_uconst */ \ 9: /* This is where the pt_regs pointer can be found on the stack. */ #define PTREGS 64+28 /* Size of regs. */ #define RSIZE 4 /* This is the offset of the VMX regs. */ #define VREGS 48*RSIZE+34*8 /* Describe where general purpose regs are saved. */ #define EH_FRAME_GEN \ cfa_save; \ rsave ( 0, 0*RSIZE); \ rsave ( 2, 2*RSIZE); \ rsave ( 3, 3*RSIZE); \ rsave ( 4, 4*RSIZE); \ rsave ( 5, 5*RSIZE); \ rsave ( 6, 6*RSIZE); \ rsave ( 7, 7*RSIZE); \ rsave ( 8, 8*RSIZE); \ rsave ( 9, 9*RSIZE); \ rsave (10, 10*RSIZE); \ rsave (11, 11*RSIZE); \ rsave (12, 12*RSIZE); \ rsave (13, 13*RSIZE); \ rsave (14, 14*RSIZE); \ rsave (15, 15*RSIZE); \ rsave (16, 16*RSIZE); \ rsave (17, 17*RSIZE); \ rsave (18, 18*RSIZE); \ rsave (19, 19*RSIZE); \ rsave (20, 20*RSIZE); \ rsave (21, 21*RSIZE); \ rsave (22, 22*RSIZE); \ rsave (23, 23*RSIZE); \ rsave (24, 24*RSIZE); \ rsave (25, 25*RSIZE); \ rsave (26, 26*RSIZE); \ rsave (27, 27*RSIZE); \ rsave (28, 28*RSIZE); \ rsave (29, 29*RSIZE); \ rsave (30, 30*RSIZE); \ rsave (31, 31*RSIZE); \ rsave (67, 32*RSIZE); /* ap, used as temp for nip */ \ rsave (65, 36*RSIZE); /* lr */ \ rsave (70, 38*RSIZE) /* cr */ /* Describe where the FP regs are saved. */ #define EH_FRAME_FP \ rsave (32, 48*RSIZE + 0*8); \ rsave (33, 48*RSIZE + 1*8); \ rsave (34, 48*RSIZE + 2*8); \ rsave (35, 48*RSIZE + 3*8); \ rsave (36, 48*RSIZE + 4*8); \ rsave (37, 48*RSIZE + 5*8); \ rsave (38, 48*RSIZE + 6*8); \ rsave (39, 48*RSIZE + 7*8); \ rsave (40, 48*RSIZE + 8*8); \ rsave (41, 48*RSIZE + 9*8); \ rsave (42, 48*RSIZE + 10*8); \ rsave (43, 48*RSIZE + 11*8); \ rsave (44, 48*RSIZE + 12*8); \ rsave (45, 48*RSIZE + 13*8); \ rsave (46, 48*RSIZE + 14*8); \ rsave (47, 48*RSIZE + 15*8); \ rsave (48, 48*RSIZE + 16*8); \ rsave (49, 48*RSIZE + 17*8); \ rsave (50, 48*RSIZE + 18*8); \ rsave (51, 48*RSIZE + 19*8); \ rsave (52, 48*RSIZE + 20*8); \ rsave (53, 48*RSIZE + 21*8); \ rsave (54, 48*RSIZE + 22*8); \ rsave (55, 48*RSIZE + 23*8); \ rsave (56, 48*RSIZE + 24*8); \ rsave (57, 48*RSIZE + 25*8); \ rsave (58, 48*RSIZE + 26*8); \ rsave (59, 48*RSIZE + 27*8); \ rsave (60, 48*RSIZE + 28*8); \ rsave (61, 48*RSIZE + 29*8); \ rsave (62, 48*RSIZE + 30*8); \ rsave (63, 48*RSIZE + 31*8) /* Describe where the VMX regs are saved. */ #ifdef CONFIG_ALTIVEC #define EH_FRAME_VMX \ vsave_msr0 ( 0); \ vsave_msr1 ( 1); \ vsave_msr1 ( 2); \ vsave_msr1 ( 3); \ vsave_msr1 ( 4); \ vsave_msr1 ( 5); \ vsave_msr1 ( 6); \ vsave_msr1 ( 7); \ vsave_msr1 ( 8); \ vsave_msr1 ( 9); \ vsave_msr1 (10); \ vsave_msr1 (11); \ vsave_msr1 (12); \ vsave_msr1 (13); \ vsave_msr1 (14); \ vsave_msr1 (15); \ vsave_msr1 (16); \ vsave_msr1 (17); \ vsave_msr1 (18); \ vsave_msr1 (19); \ vsave_msr1 (20); \ vsave_msr1 (21); \ vsave_msr1 (22); \ vsave_msr1 (23); \ vsave_msr1 (24); \ vsave_msr1 (25); \ vsave_msr1 (26); \ vsave_msr1 (27); \ vsave_msr1 (28); \ vsave_msr1 (29); \ vsave_msr1 (30); \ vsave_msr1 (31); \ vsave_msr2 (33, 32*16+12); \ vsave (32, 32*16) #else #define EH_FRAME_VMX #endif .Lcie: .long .Lcie_end - .Lcie_start .Lcie_start: .long 0 /* CIE ID */ .byte 1 /* Version number */ .string "zR" /* NUL-terminated augmentation string */ .uleb128 4 /* Code alignment factor */ .sleb128 -4 /* Data alignment factor */ .byte 67 /* Return address register column, ap */ .uleb128 1 /* Augmentation value length */ .byte 0x1b /* DW_EH_PE_pcrel | DW_EH_PE_sdata4. */ .byte 0x0c,1,0 /* DW_CFA_def_cfa: r1 ofs 0 */ .balign 4 .Lcie_end: .long .Lfde0_end - .Lfde0_start .Lfde0_start: .long .Lfde0_start - .Lcie /* CIE pointer. */ .long .Lsig_start - . /* PC start, length */ .long .Lsig_end - .Lsig_start .uleb128 0 /* Augmentation */ EH_FRAME_GEN EH_FRAME_FP EH_FRAME_VMX .balign 4 .Lfde0_end: /* We have a different stack layout for rt_sigreturn. */ #undef PTREGS #define PTREGS 64+16+128+20+28 .long .Lfde1_end - .Lfde1_start .Lfde1_start: .long .Lfde1_start - .Lcie /* CIE pointer. */ .long .Lsigrt_start - . /* PC start, length */ .long .Lsigrt_end - .Lsigrt_start .uleb128 0 /* Augmentation */ EH_FRAME_GEN EH_FRAME_FP EH_FRAME_VMX .balign 4 .Lfde1_end: