Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 16203a7a authored by Rob Landley's avatar Rob Landley Committed by Linus Torvalds
Browse files

initmpfs: make rootfs use tmpfs when CONFIG_TMPFS enabled 



Conditionally call the appropriate fs_init function and fill_super
functions.  Add a use once guard to shmem_init() to simply succeed on a
second call.

(Note that IS_ENABLED() is a compile time constant so dead code
elimination removes unused function calls when CONFIG_TMPFS is disabled.)

Signed-off-by: default avatarRob Landley <rob@landley.net>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jim Cromie <jim.cromie@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 57f150a5

init/do_mounts.c

+8 −2
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ 
#include <linux/fs_struct.h>

#include <linux/slab.h>

#include <linux/ramfs.h>

#include <linux/shmem_fs.h>



#include <linux/nfs_fs.h>

#include <linux/nfs_fs_sb.h>
@@ -598,7 +599,8 @@ static struct dentry *rootfs_mount(struct file_system_type *fs_type, 
	if (test_and_set_bit(0, &once))

		return ERR_PTR(-ENODEV);



	return mount_nodev(fs_type, flags, data, ramfs_fill_super);

	return mount_nodev(fs_type, flags, data,

		IS_ENABLED(CONFIG_TMPFS) ? shmem_fill_super : ramfs_fill_super);

}



static struct file_system_type rootfs_fs_type = {
@@ -614,7 +616,11 @@ int __init init_rootfs(void) 
	if (err)

		return err;



	if (IS_ENABLED(CONFIG_TMPFS))

		err = shmem_init();

	else

		err = init_ramfs_fs();



	if (err)

		unregister_filesystem(&rootfs_fs_type);

mm/shmem.c

+4 −0
Original line number Diff line number Diff line
@@ -2819,6 +2819,10 @@ int __init shmem_init(void) 
{

	int error;



	/* If rootfs called this, don't re-init */

	if (shmem_inode_cachep)

		return 0;



	error = bdi_init(&shmem_backing_dev_info);

	if (error)

		goto out4;