On Wed, May 17, 2023 at 09:57:55AM +0200, Christian Brauner wrote: > BTW, why is there no code to lookup a bdev by O_PATH fd? It seems weird > that a lot of ioctls pass the device path to the kernel (btrfs comes to > mind). I can see certain things that would make this potentially a bit > tricky e.g., you'd not have access to the path/name of the device if you > want to show it somewhere such as in mountinfo but nothing that makes it > impossible afaict. As far as I can tell you should be able to hold a reference to a block device file descriptor with an O_PATH fd. Or did I miss something that specifically prohibits that? > Yeah, I'll get to this soon. Josef has mentioned that he'll convert > btrfs to the new mount api this cycle and we have that recorded on > video. And I think that otherwise all block device based filesystems > might have already been converted. Btrfs is the last "big" file system, but there plenty more. A quick grep for mount_bdev fills more than a page on my terminal..