[PATCH 063/109] fanotify: add do_fanotify_mark() helper; remove in-kernel call to syscall

From: Dominik Brodowski
Date: Thu Mar 29 2018 - 07:51:48 EST


Using the fs-internal do_fanotify_mark() helper allows us to get rid of
the fs-internal call to the sys_fanotify_mark() 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

Acked-by: Jan Kara <jack@xxxxxxx>
Cc: Amir Goldstein <amir73il@xxxxxxxxx>
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Signed-off-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
---
fs/notify/fanotify/fanotify_user.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index c07eb3d655ea..fa803a58a605 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -820,9 +820,8 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
return fd;
}

-SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags,
- __u64, mask, int, dfd,
- const char __user *, pathname)
+static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
+ int dfd, const char __user *pathname)
{
struct inode *inode = NULL;
struct vfsmount *mnt = NULL;
@@ -928,13 +927,20 @@ SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags,
return ret;
}

+SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags,
+ __u64, mask, int, dfd,
+ const char __user *, pathname)
+{
+ return do_fanotify_mark(fanotify_fd, flags, mask, dfd, pathname);
+}
+
#ifdef CONFIG_COMPAT
COMPAT_SYSCALL_DEFINE6(fanotify_mark,
int, fanotify_fd, unsigned int, flags,
__u32, mask0, __u32, mask1, int, dfd,
const char __user *, pathname)
{
- return sys_fanotify_mark(fanotify_fd, flags,
+ return do_fanotify_mark(fanotify_fd, flags,
#ifdef __BIG_ENDIAN
((__u64)mask0 << 32) | mask1,
#else
--
2.16.3