Subject: mmap() from kernel to user
To: None <firstname.lastname@example.org>
From: Kamal R. Prasad <email@example.com>
Date: 11/22/2004 01:34:52
I have a device driver in the works for a usb device. I want to
mmap(ANON_MAP) and pass the fd to userspace and have it read the fd for
the bulk data obtained by the kernel. Is that possible? Or do I have
mmap() named files and pass the name only?
Secondly, it looks like the USB framework mandates something like 1024
bytes [or maybe slightly more] that can be read from a bulk pipe. My usb
device generates a lot more data possibly a 1024x1024 image. So, do I
need to do something besides reading it at my own pace? Will there be
an overflow or lost data? Forgive me if the questions are a bit naive.