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Mapping kernel memory into user space?

Mapping kernel memory into user space?

Post by Felix Rau » Sat, 02 May 1998 04:00:00



I should map some piece of kernel-memory into user space for a driver.
I know that there is a good driver-book out there which I will
soon buy. But for now, I need a solution before I have the book.

I already have a kernel-module and a device special file /dev/memmap.
A user-space programm can open(2) the /dev/memmap file, do an
ioctl(2) syscall to have the kernel module kmalloc() some kB of
memory.

Now I should (either with another ioctl() or with an mmap() call)
map this allocated piece of memory into user space, so that the
user space programm can read an write to it. Another user space
programm should also be able to read an write to it (as well as the
kernel space driver of course).

How do I map that memory from the kernel module to the user space?

- Felix
--

Homepage: http://nice.ethz.ch/~felix/ (includes PGP public key)

 
 
 
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