From a90f590a1bee36fc2129cfb38ceec24a555bb12d Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Sun, 11 Mar 2018 11:34:46 +0100 Subject: mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff() Using this helper allows us to avoid the in-kernel calls to the sys_mmap_pgoff() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_mmap_pgoff(). 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: Andrew Morton Cc: linux-mm@kvack.org Signed-off-by: Dominik Brodowski --- mm/mmap.c | 17 ++++++++++++----- mm/nommu.c | 17 ++++++++++++----- 2 files changed, 24 insertions(+), 10 deletions(-) (limited to 'mm') diff --git a/mm/mmap.c b/mm/mmap.c index 9efdc021ad22..aa0dc8231c0d 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1488,9 +1488,9 @@ unsigned long do_mmap(struct file *file, unsigned long addr, return addr; } -SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, - unsigned long, prot, unsigned long, flags, - unsigned long, fd, unsigned long, pgoff) +unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len, + unsigned long prot, unsigned long flags, + unsigned long fd, unsigned long pgoff) { struct file *file = NULL; unsigned long retval; @@ -1537,6 +1537,13 @@ out_fput: return retval; } +SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, + unsigned long, prot, unsigned long, flags, + unsigned long, fd, unsigned long, pgoff) +{ + return ksys_mmap_pgoff(addr, len, prot, flags, fd, pgoff); +} + #ifdef __ARCH_WANT_SYS_OLD_MMAP struct mmap_arg_struct { unsigned long addr; @@ -1556,8 +1563,8 @@ SYSCALL_DEFINE1(old_mmap, struct mmap_arg_struct __user *, arg) if (offset_in_page(a.offset)) return -EINVAL; - return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, - a.offset >> PAGE_SHIFT); + return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, + a.offset >> PAGE_SHIFT); } #endif /* __ARCH_WANT_SYS_OLD_MMAP */ diff --git a/mm/nommu.c b/mm/nommu.c index ebb6e618dade..cad329629530 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1423,9 +1423,9 @@ error_getting_region: return -ENOMEM; } -SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, - unsigned long, prot, unsigned long, flags, - unsigned long, fd, unsigned long, pgoff) +unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len, + unsigned long prot, unsigned long flags, + unsigned long fd, unsigned long pgoff) { struct file *file = NULL; unsigned long retval = -EBADF; @@ -1447,6 +1447,13 @@ out: return retval; } +SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len, + unsigned long, prot, unsigned long, flags, + unsigned long, fd, unsigned long, pgoff) +{ + return ksys_mmap_pgoff(addr, len, prot, flags, fd, pgoff); +} + #ifdef __ARCH_WANT_SYS_OLD_MMAP struct mmap_arg_struct { unsigned long addr; @@ -1466,8 +1473,8 @@ SYSCALL_DEFINE1(old_mmap, struct mmap_arg_struct __user *, arg) if (offset_in_page(a.offset)) return -EINVAL; - return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, - a.offset >> PAGE_SHIFT); + return ksys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, + a.offset >> PAGE_SHIFT); } #endif /* __ARCH_WANT_SYS_OLD_MMAP */ -- cgit v1.2.3