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 <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 16:20:01 +01:00
parent e7dc9ad6e9
commit af03c4acb7

View File

@ -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,