![Dominik Brodowski](/assets/img/avatar_default.png)
Using this helper allows us to avoid the in-kernel calls to the sys_mmap_pgoff() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_mmap_pgoff(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-mm@kvack.org Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
66 lines
1.9 KiB
C
66 lines
1.9 KiB
C
/*
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* AArch64-specific system calls implementation
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*
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* Copyright (C) 2012 ARM Ltd.
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* Author: Catalin Marinas <catalin.marinas@arm.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <linux/compiler.h>
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#include <linux/errno.h>
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#include <linux/fs.h>
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#include <linux/mm.h>
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#include <linux/export.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/syscalls.h>
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#include <asm/cpufeature.h>
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asmlinkage long sys_mmap(unsigned long addr, unsigned long len,
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unsigned long prot, unsigned long flags,
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unsigned long fd, off_t off)
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{
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if (offset_in_page(off) != 0)
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return -EINVAL;
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return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
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}
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SYSCALL_DEFINE1(arm64_personality, unsigned int, personality)
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{
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if (personality(personality) == PER_LINUX32 &&
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!system_supports_32bit_el0())
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return -EINVAL;
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return sys_personality(personality);
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}
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/*
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* Wrappers to pass the pt_regs argument.
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*/
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asmlinkage long sys_rt_sigreturn_wrapper(void);
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#define sys_rt_sigreturn sys_rt_sigreturn_wrapper
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#define sys_personality sys_arm64_personality
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#undef __SYSCALL
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#define __SYSCALL(nr, sym) [nr] = sym,
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/*
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* The sys_call_table array must be 4K aligned to be accessible from
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* kernel/entry.S.
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*/
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void * const sys_call_table[__NR_syscalls] __aligned(4096) = {
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[0 ... __NR_syscalls - 1] = sys_ni_syscall,
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#include <asm/unistd.h>
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};
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