From b6e9b0babb7a02ae4f00f053974609000f00950e Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Sat, 17 Mar 2018 16:00:25 +0100 Subject: mm: add kernel_migrate_pages() helper, move compat syscall to mm/mempolicy.c Move compat_sys_migrate_pages() to mm/mempolicy.c and make it call a newly introduced helper -- kernel_migrate_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 Cc: linux-mm@kvack.org Cc: Andrew Morton Signed-off-by: Dominik Brodowski --- kernel/compat.c | 33 --------------------------------- 1 file changed, 33 deletions(-) (limited to 'kernel/compat.c') diff --git a/kernel/compat.c b/kernel/compat.c index 3f5fa8902e7d..51bdf1808943 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -508,39 +508,6 @@ COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages, } return sys_move_pages(pid, nr_pages, pages, nodes, status, flags); } - -COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid, - compat_ulong_t, maxnode, - const compat_ulong_t __user *, old_nodes, - const compat_ulong_t __user *, new_nodes) -{ - unsigned long __user *old = NULL; - unsigned long __user *new = NULL; - nodemask_t tmp_mask; - unsigned long nr_bits; - unsigned long size; - - nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES); - size = ALIGN(nr_bits, BITS_PER_LONG) / 8; - if (old_nodes) { - if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits)) - return -EFAULT; - old = compat_alloc_user_space(new_nodes ? size * 2 : size); - if (new_nodes) - new = old + size / sizeof(unsigned long); - if (copy_to_user(old, nodes_addr(tmp_mask), size)) - return -EFAULT; - } - if (new_nodes) { - if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits)) - return -EFAULT; - if (new == NULL) - new = compat_alloc_user_space(size); - if (copy_to_user(new, nodes_addr(tmp_mask), size)) - return -EFAULT; - } - return sys_migrate_pages(pid, nr_bits + 1, old, new); -} #endif /* -- cgit