mm: add kernel_move_pages() helper, move compat syscall to mm/migrate.c

Move compat_sys_move_pages() to mm/migrate.c and make it call a newly
introduced helper -- kernel_move_pages() -- instead of the syscall.

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: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
This commit is contained in:
Dominik Brodowski
2018-03-17 16:08:03 +01:00
parent b6e9b0babb
commit 7addf44388
2 changed files with 35 additions and 26 deletions

View File

@@ -488,28 +488,6 @@ get_compat_sigset(sigset_t *set, const compat_sigset_t __user *compat)
}
EXPORT_SYMBOL_GPL(get_compat_sigset);
#ifdef CONFIG_NUMA
COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages,
compat_uptr_t __user *, pages32,
const int __user *, nodes,
int __user *, status,
int, flags)
{
const void __user * __user *pages;
int i;
pages = compat_alloc_user_space(nr_pages * sizeof(void *));
for (i = 0; i < nr_pages; i++) {
compat_uptr_t p;
if (get_user(p, pages32 + i) ||
put_user(compat_ptr(p), pages + i))
return -EFAULT;
}
return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
}
#endif
/*
* Allocate user-space memory for the duration of a single system call,
* in order to marshall parameters inside a compat thunk.