Re: semaphore woes in 2.6, 32bit

[Ralf Baechle <ralf@linux-mips.org>]

On Mon, May 10, 2004 at 10:28:45PM +0900, Atsushi Nemoto wrote:

> >> Hmm, many drivers use kmalloc and pci_map_single for DMA buffer.
> >> So ARCH_KMALLOC_MINALIGN should be L1_CACHE_BYTES for non-coherent
> >> system?
> 
> ralf> No, those drivers are simply broken.  dma_get_cache_alignment()
> ralf> gives the mimimum alignment and width for DMA mappings and that
> ralf> value is larger than kmalloc alignment in almost all cases.
> 
> I see.  Thank you for pointing out it.  I must learn 2.6 DMA API
> quickly ...

This also applies to the 2.4 PCI DMA API.

  Ralf