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>
This commit is contained in:
Dominik Brodowski
2018-03-11 11:34:46 +01:00
parent 9d5b7c956b
commit a90f590a1b
21 changed files with 60 additions and 41 deletions

View File

@@ -270,8 +270,8 @@ asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
{
/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
we have. */
return sys_mmap_pgoff(addr, len, prot, flags, fd,
pgoff >> (PAGE_SHIFT - 12));
return ksys_mmap_pgoff(addr, len, prot, flags, fd,
pgoff >> (PAGE_SHIFT - 12));
}
asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
@@ -279,7 +279,7 @@ asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
unsigned long offset)
{
if (!(offset & ~PAGE_MASK)) {
return sys_mmap_pgoff(addr, len, prot, flags, fd,
return ksys_mmap_pgoff(addr, len, prot, flags, fd,
offset >> PAGE_SHIFT);
} else {
return -EINVAL;