|  | /* | 
|  | * Signal trampoline for 64 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 <asm/processor.h> | 
|  | #include <asm/ppc_asm.h> | 
|  | #include <asm/unistd.h> | 
|  | #include <asm/vdso.h> | 
|  | #include <asm/ptrace.h>		/* XXX for __SIGNAL_FRAMESIZE */ | 
|  |  | 
|  | .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 padding before the | 
|  | real start.  */ | 
|  | nop | 
|  | .balign 8 | 
|  | V_FUNCTION_BEGIN(__kernel_sigtramp_rt64) | 
|  | .Lsigrt_start = . - 4 | 
|  | addi	r1, r1, __SIGNAL_FRAMESIZE | 
|  | li	r0,__NR_rt_sigreturn | 
|  | sc | 
|  | .Lsigrt_end: | 
|  | V_FUNCTION_END(__kernel_sigtramp_rt64) | 
|  | /* The ".balign 8" above and the following zeros mimic the old stack | 
|  | trampoline layout.  The last magic value is the ucontext pointer, | 
|  | chosen in such a way that older libgcc unwind code returns a zero | 
|  | for a sigcontext pointer.  */ | 
|  | .long 0,0,0 | 
|  | .quad 0,-21*8 | 
|  |  | 
|  | /* Register r1 can be found at offset 8 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.  A pointer to the VMX reg struct is at VREGS in | 
|  | 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 0x06;			/*     DW_OP_deref */			\ | 
|  | .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 0x06;			/*     DW_OP_deref */			\ | 
|  | .byte 0x23; .uleb128 ofs;	/*     DW_OP_plus_uconst */		\ | 
|  | 9: | 
|  |  | 
|  | /* This is where the pt_regs pointer can be found on the stack.  */ | 
|  | #define PTREGS	128+168+56 | 
|  |  | 
|  | /* Size of regs.  */ | 
|  | #define RSIZE	8 | 
|  |  | 
|  | /* Size of CR reg in DWARF unwind info. */ | 
|  | #define CRSIZE	4 | 
|  |  | 
|  | /* This is the offset of the VMX reg pointer.  */ | 
|  | #define VREGS	48*RSIZE+33*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 + (RSIZE - CRSIZE)) /* 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, 33*16) | 
|  | #else | 
|  | #define EH_FRAME_VMX | 
|  | #endif | 
|  |  | 
|  | .section .eh_frame,"a",@progbits | 
|  | .Lcie: | 
|  | .long .Lcie_end - .Lcie_start | 
|  | .Lcie_start: | 
|  | .long 0			/* CIE ID */ | 
|  | .byte 1			/* Version number */ | 
|  | .string "zRS"		/* NUL-terminated augmentation string */ | 
|  | .uleb128 4		/* Code alignment factor */ | 
|  | .sleb128 -8		/* Data alignment factor */ | 
|  | .byte 67		/* Return address register column, ap */ | 
|  | .uleb128 1		/* Augmentation value length */ | 
|  | .byte 0x14		/* DW_EH_PE_pcrel | DW_EH_PE_udata8. */ | 
|  | .byte 0x0c,1,0		/* DW_CFA_def_cfa: r1 ofs 0 */ | 
|  | .balign 8 | 
|  | .Lcie_end: | 
|  |  | 
|  | .long .Lfde0_end - .Lfde0_start | 
|  | .Lfde0_start: | 
|  | .long .Lfde0_start - .Lcie	/* CIE pointer. */ | 
|  | .quad .Lsigrt_start - .		/* PC start, length */ | 
|  | .quad .Lsigrt_end - .Lsigrt_start | 
|  | .uleb128 0			/* Augmentation */ | 
|  | EH_FRAME_GEN | 
|  | EH_FRAME_FP | 
|  | EH_FRAME_VMX | 
|  | # Do we really need to describe the frame at this point?  ie. will | 
|  | # we ever have some call chain that returns somewhere past the addi? | 
|  | # I don't think so, since gcc doesn't support async signals. | 
|  | #	.byte 0x41		/* DW_CFA_advance_loc 1*4 */ | 
|  | #undef PTREGS | 
|  | #define PTREGS 168+56 | 
|  | #	EH_FRAME_GEN | 
|  | #	EH_FRAME_FP | 
|  | #	EH_FRAME_VMX | 
|  | .balign 8 | 
|  | .Lfde0_end: |