314 lines
10 KiB
ArmAsm
314 lines
10 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
|
/*
|
|
* 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.
|
|
*/
|
|
#include <asm/cache.h> /* IFETCH_ALIGN_BYTES */
|
|
#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
|
|
|
|
/*
|
|
* __kernel_start_sigtramp_rt64 and __kernel_sigtramp_rt64 together
|
|
* are one function split in two parts. The kernel jumps to the former
|
|
* and the signal handler indirectly (by blr) returns to the latter.
|
|
* __kernel_sigtramp_rt64 needs to point to the return address so
|
|
* glibc can correctly identify the trampoline stack frame.
|
|
*/
|
|
.balign 8
|
|
.balign IFETCH_ALIGN_BYTES
|
|
V_FUNCTION_BEGIN(__kernel_start_sigtramp_rt64)
|
|
.Lsigrt_start:
|
|
bctrl /* call the handler */
|
|
V_FUNCTION_END(__kernel_start_sigtramp_rt64)
|
|
V_FUNCTION_BEGIN(__kernel_sigtramp_rt64)
|
|
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
|
|
|
|
/* Offset of CR reg within a full word. */
|
|
#ifdef __LITTLE_ENDIAN__
|
|
#define CROFF 0
|
|
#else
|
|
#define CROFF (RSIZE - CRSIZE)
|
|
#endif
|
|
|
|
/* 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 (68, 38*RSIZE + CROFF); /* cr fields */ \
|
|
rsave (69, 38*RSIZE + CROFF); \
|
|
rsave (70, 38*RSIZE + CROFF); \
|
|
rsave (71, 38*RSIZE + CROFF); \
|
|
rsave (72, 38*RSIZE + CROFF); \
|
|
rsave (73, 38*RSIZE + CROFF); \
|
|
rsave (74, 38*RSIZE + CROFF); \
|
|
rsave (75, 38*RSIZE + CROFF)
|
|
|
|
/* 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:
|