How to port the mmap function?

Altera_Forum · ‎01-24-2005

One Unix implementation use the mmap function and /dev/zero to fulfill the virtual memory.

How could I port such functionality onto Nios II? Must I include the OS? Can HAL solve the problem?

Altera_Forum · ‎01-24-2005

Hi neo,

> ... use the mmap function and /dev/zero to fulfill the virtual memory.

> How could I port such functionality onto Nios II?

I'm not sure what you're asking ... Nios-II does not have

an MMU ... there's no virtual memory. Do you just want to

clear memory?

Regards,

--Scott

Altera_Forum · ‎01-25-2005

What are you planning to use your virtual memory for, and what will you use as the backing store for it?

Neither the HAL nor any other OS I'm aware of supports virtual memory (or the mmap function) - as has been pointed out it will be hard for them to do so until we have an MMU.

As I said in another post, it might be possible, without an MMU, to implement a subset of mmap for file access, but it will be less efficient than using read/write.