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Commit 9e7fdd25 authored by Eric W. Biederman's avatar Eric W. Biederman Committed by Greg Kroah-Hartman
Browse files

sysfs: Basic support for multiple super blocks 



Add all of the necessary bioler plate to support
multiple superblocks in sysfs.

Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
Acked-by: default avatarSerge Hallyn <serue@us.ibm.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent c3473c63

fs/sysfs/mount.c

+56 −2
Original line number Diff line number Diff line
@@ -72,16 +72,70 @@ static int sysfs_fill_super(struct super_block *sb, void *data, int silent) 
	return 0;

}



static int sysfs_test_super(struct super_block *sb, void *data)

{

	struct sysfs_super_info *sb_info = sysfs_info(sb);

	struct sysfs_super_info *info = data;

	int found = 1;

	return found;

}



static int sysfs_set_super(struct super_block *sb, void *data)

{

	int error;

	error = set_anon_super(sb, data);

	if (!error)

		sb->s_fs_info = data;

	return error;

}



static int sysfs_get_sb(struct file_system_type *fs_type,

	int flags, const char *dev_name, void *data, struct vfsmount *mnt)

{

	return get_sb_single(fs_type, flags, data, sysfs_fill_super, mnt);

	struct sysfs_super_info *info;

	struct super_block *sb;

	int error;



	error = -ENOMEM;

	info = kzalloc(sizeof(*info), GFP_KERNEL);

	if (!info)

		goto out;

	sb = sget(fs_type, sysfs_test_super, sysfs_set_super, info);

	if (IS_ERR(sb) || sb->s_fs_info != info)

		kfree(info);

	if (IS_ERR(sb)) {

		kfree(info);

		error = PTR_ERR(sb);

		goto out;

	}

	if (!sb->s_root) {

		sb->s_flags = flags;

		error = sysfs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);

		if (error) {

			deactivate_locked_super(sb);

			goto out;

		}

		sb->s_flags |= MS_ACTIVE;

	}



	simple_set_mnt(mnt, sb);

	error = 0;

out:

	return error;

}



static void sysfs_kill_sb(struct super_block *sb)

{

	struct sysfs_super_info *info = sysfs_info(sb);



	kill_anon_super(sb);

	kfree(info);

}



static struct file_system_type sysfs_fs_type = {

	.name		= "sysfs",

	.get_sb		= sysfs_get_sb,

	.kill_sb	= kill_anon_super,

	.kill_sb	= sysfs_kill_sb,

};



int __init sysfs_init(void)

fs/sysfs/sysfs.h

+3 −0
Original line number Diff line number Diff line
@@ -114,6 +114,9 @@ struct sysfs_addrm_cxt { 
/*

 * mount.c

 */

struct sysfs_super_info {

};

#define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))

extern struct sysfs_dirent sysfs_root;

extern struct kmem_cache *sysfs_dir_cachep;