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>
diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c
index b7c816f..26f6b4f 100644
--- a/fs/autofs4/dev-ioctl.c
+++ b/fs/autofs4/dev-ioctl.c
@@ -310,7 +310,7 @@ static int autofs_dev_ioctl_closemount(struct file *fp,
struct autofs_sb_info *sbi,
struct autofs_dev_ioctl *param)
{
- return sys_close(param->ioctlfd);
+ return ksys_close(param->ioctlfd);
}
/*
diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c
index a7c5a98..a41b48f 100644
--- a/fs/binfmt_misc.c
+++ b/fs/binfmt_misc.c
@@ -241,7 +241,7 @@ static int load_misc_binary(struct linux_binprm *bprm)
return retval;
error:
if (fd_binary > 0)
- sys_close(fd_binary);
+ ksys_close(fd_binary);
bprm->interp_flags = 0;
bprm->interp_data = 0;
goto ret;
diff --git a/fs/file.c b/fs/file.c
index d304004..7ffd6e9 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -638,6 +638,7 @@ int __close_fd(struct files_struct *files, unsigned fd)
spin_unlock(&files->file_lock);
return -EBADF;
}
+EXPORT_SYMBOL(__close_fd); /* for ksys_close() */
void do_close_on_exec(struct files_struct *files)
{
diff --git a/fs/open.c b/fs/open.c
index b3f3b2c..710102f 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -1200,7 +1200,6 @@ SYSCALL_DEFINE1(close, unsigned int, fd)
return retval;
}
-EXPORT_SYMBOL(sys_close);
/*
* This routine simulates a hangup on the tty, to arrange that users