The same physical memory can be translated as user-space virtual address as well as kernel space.
See more about mmap, io_remap_pfn_range etc. and you will get an idea.
The main advantage with this u can avoid copying data between two spaces but disadvantage associated is u need to request a fixed memory chunk from kernel for this purpose.
On Tue, Jul 12, 2011 at 10:09 AM, Amit Nagal <helloin.amit@xxxxxxxxx> wrote:
Hi ,
Normally we use copy_to_user / copy_from_user api's to transfer data
to/from user space from/to kernel space .
Can i be suggested with any other data transfer mechanism b/w kernel
- user space for a char device ,
which are much faster than copy_xxx ?
Regards
Amit Nagal
_______________________________________________
Kernelnewbies mailing list
Kernelnewbies@xxxxxxxxxxxxxxxxx
http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
_______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
