1/* SPDX-License-Identifier: GPL-2.0-or-later */ 2/* 3 * Access to the shared data page by the vDSO & syscall map 4 * 5 * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp. 6 */ 7 8#include <asm/processor.h> 9#include <asm/ppc_asm.h> 10#include <asm/asm-offsets.h> 11#include <asm/unistd.h> 12#include <asm/vdso.h> 13#include <asm/vdso_datapage.h> 14 15 .text 16.global __kernel_datapage_offset; 17__kernel_datapage_offset: 18 .long 0 19 20/* 21 * void *__kernel_get_syscall_map(unsigned int *syscall_count) ; 22 * 23 * returns a pointer to the syscall map. the map is agnostic to the 24 * size of "long", unlike kernel bitops, it stores bits from top to 25 * bottom so that memory actually contains a linear bitmap 26 * check for syscall N by testing bit (0x80000000 >> (N & 0x1f)) of 27 * 32 bits int at N >> 5. 28 */ 29V_FUNCTION_BEGIN(__kernel_get_syscall_map) 30 .cfi_startproc 31 mflr r12 32 .cfi_register lr,r12 33 mr r4,r3 34 get_datapage r3, r0 35 mtlr r12 36 addi r3,r3,CFG_SYSCALL_MAP64 37 cmpldi cr0,r4,0 38 crclr cr0*4+so 39 beqlr 40 li r0,NR_syscalls 41 stw r0,0(r4) 42 blr 43 .cfi_endproc 44V_FUNCTION_END(__kernel_get_syscall_map) 45 46 47/* 48 * void unsigned long __kernel_get_tbfreq(void); 49 * 50 * returns the timebase frequency in HZ 51 */ 52V_FUNCTION_BEGIN(__kernel_get_tbfreq) 53 .cfi_startproc 54 mflr r12 55 .cfi_register lr,r12 56 get_datapage r3, r0 57 ld r3,CFG_TB_TICKS_PER_SEC(r3) 58 mtlr r12 59 crclr cr0*4+so 60 blr 61 .cfi_endproc 62V_FUNCTION_END(__kernel_get_tbfreq) 63