From af03c4acb728dd9ed850d329a1cff71d52e7f3a8 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Sat, 17 Mar 2018 16:20:01 +0100 Subject: [PATCH] mm: add kernel_[sg]et_mempolicy() helpers; remove in-kernel calls to syscalls Using the mm-internal kernel_[sg]et_mempolicy() helper allows us to get rid of the mm-internal calls to the sys_[sg]et_mempolicy() syscalls. 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 --- mm/mempolicy.c | 29 ++++++++++++++++++++++------- 1 file changed, 22 insertions(+), 7 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index e4d7d4c0b253..ca817e768d0e 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1365,8 +1365,8 @@ SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len, } /* Set the process memory policy */ -SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask, - unsigned long, maxnode) +static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask, + unsigned long maxnode) { int err; nodemask_t nodes; @@ -1384,6 +1384,12 @@ SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask, return do_set_mempolicy(mode, flags, &nodes); } +SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask, + unsigned long, maxnode) +{ + return kernel_set_mempolicy(mode, nmask, maxnode); +} + static int kernel_migrate_pages(pid_t pid, unsigned long maxnode, const unsigned long __user *old_nodes, const unsigned long __user *new_nodes) @@ -1485,9 +1491,11 @@ SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode, /* Retrieve NUMA policy */ -SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, - unsigned long __user *, nmask, unsigned long, maxnode, - unsigned long, addr, unsigned long, flags) +static int kernel_get_mempolicy(int __user *policy, + unsigned long __user *nmask, + unsigned long maxnode, + unsigned long addr, + unsigned long flags) { int err; int uninitialized_var(pval); @@ -1510,6 +1518,13 @@ SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, return err; } +SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, + unsigned long __user *, nmask, unsigned long, maxnode, + unsigned long, addr, unsigned long, flags) +{ + return kernel_get_mempolicy(policy, nmask, maxnode, addr, flags); +} + #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, @@ -1528,7 +1543,7 @@ COMPAT_SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, if (nmask) nm = compat_alloc_user_space(alloc_size); - err = sys_get_mempolicy(policy, nm, nr_bits+1, addr, flags); + err = kernel_get_mempolicy(policy, nm, nr_bits+1, addr, flags); if (!err && nmask) { unsigned long copy_size; @@ -1560,7 +1575,7 @@ COMPAT_SYSCALL_DEFINE3(set_mempolicy, int, mode, compat_ulong_t __user *, nmask, return -EFAULT; } - return sys_set_mempolicy(mode, nm, nr_bits+1); + return kernel_set_mempolicy(mode, nm, nr_bits+1); } COMPAT_SYSCALL_DEFINE6(mbind, compat_ulong_t, start, compat_ulong_t, len, -- 2.30.2