linux-stable/init/do_mounts.h
Dominik Brodowski 87c4e19262 fs: add do_mknodat() helper and ksys_mknod() wrapper; remove in-kernel calls to syscall
Using the fs-internal do_mknodat() helper allows us to get rid of
fs-internal calls to the sys_mknodat() syscall.

Introducing the ksys_mknod() wrapper allows us to avoid the in-kernel
calls to sys_mknod() 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_mknod().

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>
2018-04-02 20:15:56 +02:00

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1.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/kernel.h>
#include <linux/blkdev.h>
#include <linux/init.h>
#include <linux/syscalls.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/mount.h>
#include <linux/major.h>
#include <linux/root_dev.h>
void change_floppy(char *fmt, ...);
void mount_block_root(char *name, int flags);
void mount_root(void);
extern int root_mountflags;
static inline int create_dev(char *name, dev_t dev)
{
ksys_unlink(name);
return ksys_mknod(name, S_IFBLK|0600, new_encode_dev(dev));
}
static inline u32 bstat(char *name)
{
struct kstat stat;
if (vfs_stat(name, &stat) != 0)
return 0;
if (!S_ISBLK(stat.mode))
return 0;
return stat.rdev;
}
#ifdef CONFIG_BLK_DEV_RAM
int __init rd_load_disk(int n);
int __init rd_load_image(char *from);
#else
static inline int rd_load_disk(int n) { return 0; }
static inline int rd_load_image(char *from) { return 0; }
#endif
#ifdef CONFIG_BLK_DEV_INITRD
bool __init initrd_load(void);
#else
static inline bool initrd_load(void) { return false; }
#endif
#ifdef CONFIG_BLK_DEV_MD
void md_run_setup(void);
#else
static inline void md_run_setup(void) {}
#endif