Using the mm-internal kernel_mbind() helper allows us to get rid of the mm-internal call to the sys_mbind() 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@xxxxxxxxxxxxxxxxxxxxxxxxxx Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: linux-mm@xxxxxxxxx Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx> --- mm/mempolicy.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 7399ede02b5f..e4d7d4c0b253 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1336,9 +1336,9 @@ static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0; } -SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len, - unsigned long, mode, const unsigned long __user *, nmask, - unsigned long, maxnode, unsigned, flags) +static long kernel_mbind(unsigned long start, unsigned long len, + unsigned long mode, const unsigned long __user *nmask, + unsigned long maxnode, unsigned int flags) { nodemask_t nodes; int err; @@ -1357,6 +1357,13 @@ SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len, return do_mbind(start, len, mode, mode_flags, &nodes, flags); } +SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len, + unsigned long, mode, const unsigned long __user *, nmask, + unsigned long, maxnode, unsigned int, flags) +{ + return kernel_mbind(start, len, mode, nmask, maxnode, flags); +} + /* Set the process memory policy */ SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask, unsigned long, maxnode) @@ -1575,7 +1582,7 @@ COMPAT_SYSCALL_DEFINE6(mbind, compat_ulong_t, start, compat_ulong_t, len, return -EFAULT; } - return sys_mbind(start, len, mode, nm, nr_bits+1, flags); + return kernel_mbind(start, len, mode, nm, nr_bits+1, flags); } COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid, -- 2.16.3
