devtmpfs: support !CONFIG_TMPFS

Make devtmpfs available on (embedded) configurations without SHMEM/TMPFS,
using ramfs instead.

Saves ~15KB.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Peter Korsgaard 2010-03-16 21:55:21 +01:00 committed by Greg Kroah-Hartman
parent 1653268b1b
commit da5e4ef7fd
4 changed files with 13 additions and 3 deletions

View File

@ -18,9 +18,9 @@ config UEVENT_HELPER_PATH
config DEVTMPFS
bool "Maintain a devtmpfs filesystem to mount at /dev"
depends on HOTPLUG && SHMEM && TMPFS
depends on HOTPLUG
help
This creates a tmpfs filesystem instance early at bootup.
This creates a tmpfs/ramfs filesystem instance early at bootup.
In this filesystem, the kernel driver core maintains device
nodes with their default names and permissions for all
registered devices with an assigned major/minor number.
@ -33,6 +33,9 @@ config DEVTMPFS
functional /dev without any further help. It also allows simple
rescue systems, and reliably handles dynamic major/minor numbers.
Notice: if CONFIG_TMPFS isn't enabled, the simpler ramfs
file system will be used instead.
config DEVTMPFS_MOUNT
bool "Automount devtmpfs at /dev, after the kernel mounted the rootfs"
depends on DEVTMPFS

View File

@ -20,6 +20,7 @@
#include <linux/namei.h>
#include <linux/fs.h>
#include <linux/shmem_fs.h>
#include <linux/ramfs.h>
#include <linux/cred.h>
#include <linux/sched.h>
#include <linux/init_task.h>
@ -45,7 +46,11 @@ __setup("devtmpfs.mount=", mount_param);
static int dev_get_sb(struct file_system_type *fs_type, int flags,
const char *dev_name, void *data, struct vfsmount *mnt)
{
#ifdef CONFIG_TMPFS
return get_sb_single(fs_type, flags, data, shmem_fill_super, mnt);
#else
return get_sb_single(fs_type, flags, data, ramfs_fill_super, mnt);
#endif
}
static struct file_system_type dev_fs_type = {

View File

@ -214,7 +214,7 @@ static int ramfs_parse_options(char *data, struct ramfs_mount_opts *opts)
return 0;
}
static int ramfs_fill_super(struct super_block * sb, void * data, int silent)
int ramfs_fill_super(struct super_block *sb, void *data, int silent)
{
struct ramfs_fs_info *fsi;
struct inode *inode = NULL;

View File

@ -20,4 +20,6 @@ extern const struct file_operations ramfs_file_operations;
extern const struct vm_operations_struct generic_file_vm_ops;
extern int __init init_rootfs(void);
int ramfs_fill_super(struct super_block *sb, void *data, int silent);
#endif