Re: [PATCH v2 0/3] usb: gadget: functionfs: DMABUF import interface

From: Andrzej Pietrasiewicz
Date: Fri Mar 31 2023 - 05:41:09 EST


Hi Paul,

W dniu 22.03.2023 o 10:21, Paul Cercueil pisze:
Hi,

This small patchset adds three new IOCTLs that can be used to attach,
detach, or transfer from/to a DMABUF object.

Changes since v1:
- patch [2/3] is new. I had to reuse a piece of code that was already
duplicated in the driver, so I factorized the code.
- Make ffs_dma_resv_lock() static
- Add MODULE_IMPORT_NS(DMA_BUF);
- The attach/detach functions are now performed without locking the
eps_lock spinlock. The transfer function starts with the spinlock
unlocked, then locks it before allocating and queueing the USB
transfer.


Can you share an example use case for these new features?
Is there a userspace that excercises the new ioctls?

Regards,

Andrzej