fs: add ksys_close() wrapper; remove in-kernel calls to sys_close()

Using the ksys_close() wrapper allows us to get rid of in-kernel calls
to the sys_close() 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_close(), with one subtle
difference:

The few places which checked the return value did not care about the return
value re-writing in sys_close(), so simply use a wrapper around
__close_fd().

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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

1 files changed, 4 insertions, 4 deletions

diff --git a/init/do_mounts_md.c b/init/do_mounts_md.c
index 3f733c760a8c..ebd4013d589e 100644
--- a/init/do_mounts_md.c
+++ b/init/do_mounts_md.c
@@ -191,7 +191,7 @@ static void __init md_setup_drive(void)
 			printk(KERN_WARNING
 			       "md: Ignoring md=%d, already autodetected. (Use raid=noautodetect)\n",
 			       minor);
-			sys_close(fd);
+			ksys_close(fd);
 			continue;
 		}
 
@@ -243,11 +243,11 @@ static void __init md_setup_drive(void)
 			 * boot a kernel with devfs compiled in from partitioned md
 			 * array without it
 			 */
-			sys_close(fd);
+			ksys_close(fd);
 			fd = sys_open(name, 0, 0);
 			sys_ioctl(fd, BLKRRPART, 0);
 		}
-		sys_close(fd);
+		ksys_close(fd);
 	}
 }
 
@@ -297,7 +297,7 @@ static void __init autodetect_raid(void)
 	fd = sys_open("/dev/md0", 0, 0);
 	if (fd >= 0) {
 		sys_ioctl(fd, RAID_AUTORUN, raid_autopart);
-		sys_close(fd);
+		ksys_close(fd);
 	}
 }