linuxkpi: Add support for statically-allocated kfifo

[dumbbell]

Summary

The main difference with the dynamically allocated version is that the structure is initialized with DECLARE_KFIFO() which takes the number of items as an additional argument compared to DECLARE_KFIFO_PTR().

The declared structure is then initialized with INIT_KFIFO() which sets all fields to 0, except total which is computed from the size of the array passed to DECLARE_KFIFO().

The amdgpu DRM driver started to used this in Linux 6.10.

This is part of the update of DRM drivers to Linux 6.10.

Sponsored by: The FreeBSD Foundation

[bz]

sys/compat/linuxkpi/common/include/linux/kfifo.h

42

That's nitems(), could use it if you wanted.

[dumbbell]

Thank you, I used nitems().