0ad50c3896
This function is used by sparc, powerpc tile and arm64 for compat support. The patch adds a generic implementation with a wrapper for PowerPC to do the u32->int sign extension. The reason for a single patch covering powerpc, tile, sparc and arm64 is to keep it bisectable, otherwise kernel building may fail with mismatched function declarations. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [for tile] Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
88 lines
2.5 KiB
C
88 lines
2.5 KiB
C
/*
|
|
* Based on arch/arm/kernel/sys_arm.c
|
|
*
|
|
* Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c
|
|
* Copyright (C) 1995, 1996 Russell King.
|
|
* Copyright (C) 2012 ARM Ltd.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <linux/compat.h>
|
|
#include <linux/personality.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/syscalls.h>
|
|
#include <linux/uaccess.h>
|
|
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/unistd32.h>
|
|
|
|
static inline void
|
|
do_compat_cache_op(unsigned long start, unsigned long end, int flags)
|
|
{
|
|
struct mm_struct *mm = current->active_mm;
|
|
struct vm_area_struct *vma;
|
|
|
|
if (end < start || flags)
|
|
return;
|
|
|
|
down_read(&mm->mmap_sem);
|
|
vma = find_vma(mm, start);
|
|
if (vma && vma->vm_start < end) {
|
|
if (start < vma->vm_start)
|
|
start = vma->vm_start;
|
|
if (end > vma->vm_end)
|
|
end = vma->vm_end;
|
|
up_read(&mm->mmap_sem);
|
|
__flush_cache_user_range(start & PAGE_MASK, PAGE_ALIGN(end));
|
|
return;
|
|
}
|
|
up_read(&mm->mmap_sem);
|
|
}
|
|
|
|
/*
|
|
* Handle all unrecognised system calls.
|
|
*/
|
|
long compat_arm_syscall(struct pt_regs *regs)
|
|
{
|
|
unsigned int no = regs->regs[7];
|
|
|
|
switch (no) {
|
|
/*
|
|
* Flush a region from virtual address 'r0' to virtual address 'r1'
|
|
* _exclusive_. There is no alignment requirement on either address;
|
|
* user space does not need to know the hardware cache layout.
|
|
*
|
|
* r2 contains flags. It should ALWAYS be passed as ZERO until it
|
|
* is defined to be something else. For now we ignore it, but may
|
|
* the fires of hell burn in your belly if you break this rule. ;)
|
|
*
|
|
* (at a later date, we may want to allow this call to not flush
|
|
* various aspects of the cache. Passing '0' will guarantee that
|
|
* everything necessary gets flushed to maintain consistency in
|
|
* the specified region).
|
|
*/
|
|
case __ARM_NR_compat_cacheflush:
|
|
do_compat_cache_op(regs->regs[0], regs->regs[1], regs->regs[2]);
|
|
return 0;
|
|
|
|
case __ARM_NR_compat_set_tls:
|
|
current->thread.tp_value = regs->regs[0];
|
|
asm ("msr tpidrro_el0, %0" : : "r" (regs->regs[0]));
|
|
return 0;
|
|
|
|
default:
|
|
return -ENOSYS;
|
|
}
|
|
}
|