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linux-next/arch/sh/kernel/sys_sh.c
Dominik Brodowski a90f590a1b mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff()
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>
2018-04-02 20:16:11 +02:00

97 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/sh/kernel/sys_sh.c
*
* This file contains various random system calls that
* have a non-standard calling sequence on the Linux/SuperH
* platform.
*
* Taken from i386 version.
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/stat.h>
#include <linux/syscalls.h>
#include <linux/mman.h>
#include <linux/file.h>
#include <linux/utsname.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/ipc.h>
#include <asm/syscalls.h>
#include <linux/uaccess.h>
#include <asm/unistd.h>
#include <asm/cacheflush.h>
#include <asm/cachectl.h>
asmlinkage int old_mmap(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
int fd, unsigned long off)
{
if (off & ~PAGE_MASK)
return -EINVAL;
return ksys_mmap_pgoff(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
}
asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
unsigned long fd, unsigned long pgoff)
{
/*
* The shift for mmap2 is constant, regardless of PAGE_SIZE
* setting.
*/
if (pgoff & ((1 << (PAGE_SHIFT - 12)) - 1))
return -EINVAL;
pgoff >>= PAGE_SHIFT - 12;
return ksys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
}
/* sys_cacheflush -- flush (part of) the processor cache. */
asmlinkage int sys_cacheflush(unsigned long addr, unsigned long len, int op)
{
struct vm_area_struct *vma;
if ((op <= 0) || (op > (CACHEFLUSH_D_PURGE|CACHEFLUSH_I)))
return -EINVAL;
/*
* Verify that the specified address region actually belongs
* to this process.
*/
if (addr + len < addr)
return -EFAULT;
down_read(&current->mm->mmap_sem);
vma = find_vma (current->mm, addr);
if (vma == NULL || addr < vma->vm_start || addr + len > vma->vm_end) {
up_read(&current->mm->mmap_sem);
return -EFAULT;
}
switch (op & CACHEFLUSH_D_PURGE) {
case CACHEFLUSH_D_INVAL:
__flush_invalidate_region((void *)addr, len);
break;
case CACHEFLUSH_D_WB:
__flush_wback_region((void *)addr, len);
break;
case CACHEFLUSH_D_PURGE:
__flush_purge_region((void *)addr, len);
break;
}
if (op & CACHEFLUSH_I)
flush_icache_range(addr, addr+len);
up_read(&current->mm->mmap_sem);
return 0;
}