From 151060ac13144208bd7601d17e4c92c59b98072f Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 14 Apr 2009 10:54:54 +0900 Subject: CUSE: implement CUSE - Character device in Userspace CUSE enables implementing character devices in userspace. With recent additions of ioctl and poll support, FUSE already has most of what's necessary to implement character devices. All CUSE has to do is bonding all those components - FUSE, chardev and the driver model - nicely. When client opens /dev/cuse, kernel starts conversation with CUSE_INIT. The client tells CUSE which device it wants to create. As the previous patch made fuse_file usable without associated fuse_inode, CUSE doesn't create super block or inodes. It attaches fuse_file to cdev file->private_data during open and set ff->fi to NULL. The rest of the operation is almost identical to FUSE direct IO case. Each CUSE device has a corresponding directory /sys/class/cuse/DEVNAME (which is symlink to /sys/devices/virtual/class/DEVNAME if SYSFS_DEPRECATED is turned off) which hosts "waiting" and "abort" among other things. Those two files have the same meaning as the FUSE control files. The only notable lacking feature compared to in-kernel implementation is mmap support. Signed-off-by: Tejun Heo Signed-off-by: Miklos Szeredi --- fs/Kconfig | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'fs/Kconfig') diff --git a/fs/Kconfig b/fs/Kconfig index 9f7270f36b2..525da2e8f73 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -62,6 +62,16 @@ source "fs/autofs/Kconfig" source "fs/autofs4/Kconfig" source "fs/fuse/Kconfig" +config CUSE + tristate "Character device in Userpace support" + depends on FUSE_FS + help + This FUSE extension allows character devices to be + implemented in userspace. + + If you want to develop or use userspace character device + based on CUSE, answer Y or M. + config GENERIC_ACL bool select FS_POSIX_ACL -- cgit v1.2.3