Hello ! Sorry, may be I do not explain it correct, but I what to allocate buffer at fixed address in RAM. RAM of my board is visible to another computer, with which I want to make connection using this buffer. I do not know how second computer will find the buffer if it will not be at fixed address. -- Vladimir On Monday 10 January 2005 23:02, Om wrote: > Vova wote: > > But what will happen if memory which I try to remap are already in use ? > > Will kernel automatically free that memory ? > > Kernel will not free it because it is not allocated. Actually kernel > will not even see it as normal memory. If the PCI device is programmed > to exhibit the internal memory to the outside (i.e, In the BAR registers > and prefetchable/non-prefetchable registers), then only this memory > becomes visible to the kernel as PCI accessible memory. You will have to > map this memory to some address space and have your own routines to > allocate and deallocate memory from this pool. > > I hope things are more clear. > I wouls strongly suggest reading the "pci system architecture" by > shanley and anderson. > > HTH, > Om. > -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/