linux_dsm_epyc7002/arch/mips/kernel/linux32.c
Dominik Brodowski c7b95d5156 mm: add ksys_readahead() helper; remove in-kernel calls to sys_readahead()
Using this helper allows us to avoid the in-kernel calls to the
sys_readahead() 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_readahead().

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 20:16:12 +02:00

163 lines
4.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Conversion between 32-bit and 64-bit native system calls.
*
* Copyright (C) 2000 Silicon Graphics, Inc.
* Written by Ulf Carlsson (ulfc@engr.sgi.com)
*/
#include <linux/compiler.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/highuid.h>
#include <linux/resource.h>
#include <linux/highmem.h>
#include <linux/time.h>
#include <linux/times.h>
#include <linux/poll.h>
#include <linux/skbuff.h>
#include <linux/filter.h>
#include <linux/shm.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/icmpv6.h>
#include <linux/syscalls.h>
#include <linux/sysctl.h>
#include <linux/utime.h>
#include <linux/utsname.h>
#include <linux/personality.h>
#include <linux/dnotify.h>
#include <linux/binfmts.h>
#include <linux/security.h>
#include <linux/compat.h>
#include <linux/vfs.h>
#include <linux/ipc.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <net/scm.h>
#include <asm/compat-signal.h>
#include <asm/sim.h>
#include <linux/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/mman.h>
/* Use this to get at 32-bit user passed pointers. */
/* A() macro should be used for places where you e.g.
have some internal variable u32 and just want to get
rid of a compiler warning. AA() has to be used in
places where you want to convert a function argument
to 32bit pointer or when you e.g. access pt_regs
structure and want to consider 32bit registers only.
*/
#define A(__x) ((unsigned long)(__x))
#define AA(__x) ((unsigned long)((int)__x))
#ifdef __MIPSEB__
#define merge_64(r1, r2) ((((r1) & 0xffffffffUL) << 32) + ((r2) & 0xffffffffUL))
#endif
#ifdef __MIPSEL__
#define merge_64(r1, r2) ((((r2) & 0xffffffffUL) << 32) + ((r1) & 0xffffffffUL))
#endif
SYSCALL_DEFINE6(32_mmap2, unsigned long, addr, unsigned long, len,
unsigned long, prot, unsigned long, flags, unsigned long, fd,
unsigned long, pgoff)
{
if (pgoff & (~PAGE_MASK >> 12))
return -EINVAL;
return ksys_mmap_pgoff(addr, len, prot, flags, fd,
pgoff >> (PAGE_SHIFT-12));
}
#define RLIM_INFINITY32 0x7fffffff
#define RESOURCE32(x) ((x > RLIM_INFINITY32) ? RLIM_INFINITY32 : x)
struct rlimit32 {
int rlim_cur;
int rlim_max;
};
SYSCALL_DEFINE4(32_truncate64, const char __user *, path,
unsigned long, __dummy, unsigned long, a2, unsigned long, a3)
{
return ksys_truncate(path, merge_64(a2, a3));
}
SYSCALL_DEFINE4(32_ftruncate64, unsigned long, fd, unsigned long, __dummy,
unsigned long, a2, unsigned long, a3)
{
return ksys_ftruncate(fd, merge_64(a2, a3));
}
SYSCALL_DEFINE5(32_llseek, unsigned int, fd, unsigned int, offset_high,
unsigned int, offset_low, loff_t __user *, result,
unsigned int, origin)
{
return sys_llseek(fd, offset_high, offset_low, result, origin);
}
/* From the Single Unix Spec: pread & pwrite act like lseek to pos + op +
lseek back to original location. They fail just like lseek does on
non-seekable files. */
SYSCALL_DEFINE6(32_pread, unsigned long, fd, char __user *, buf, size_t, count,
unsigned long, unused, unsigned long, a4, unsigned long, a5)
{
return ksys_pread64(fd, buf, count, merge_64(a4, a5));
}
SYSCALL_DEFINE6(32_pwrite, unsigned int, fd, const char __user *, buf,
size_t, count, u32, unused, u64, a4, u64, a5)
{
return ksys_pwrite64(fd, buf, count, merge_64(a4, a5));
}
SYSCALL_DEFINE1(32_personality, unsigned long, personality)
{
unsigned int p = personality & 0xffffffff;
int ret;
if (personality(current->personality) == PER_LINUX32 &&
personality(p) == PER_LINUX)
p = (p & ~PER_MASK) | PER_LINUX32;
ret = sys_personality(p);
if (ret != -1 && personality(ret) == PER_LINUX32)
ret = (ret & ~PER_MASK) | PER_LINUX;
return ret;
}
asmlinkage ssize_t sys32_readahead(int fd, u32 pad0, u64 a2, u64 a3,
size_t count)
{
return ksys_readahead(fd, merge_64(a2, a3), count);
}
asmlinkage long sys32_sync_file_range(int fd, int __pad,
unsigned long a2, unsigned long a3,
unsigned long a4, unsigned long a5,
int flags)
{
return ksys_sync_file_range(fd,
merge_64(a2, a3), merge_64(a4, a5),
flags);
}
asmlinkage long sys32_fadvise64_64(int fd, int __pad,
unsigned long a2, unsigned long a3,
unsigned long a4, unsigned long a5,
int flags)
{
return ksys_fadvise64_64(fd,
merge_64(a2, a3), merge_64(a4, a5),
flags);
}
asmlinkage long sys32_fallocate(int fd, int mode, unsigned offset_a2,
unsigned offset_a3, unsigned len_a4, unsigned len_a5)
{
return ksys_fallocate(fd, mode, merge_64(offset_a2, offset_a3),
merge_64(len_a4, len_a5));
}