m68k: don't provide arch_dma_alloc for nommu/coldfire

Coldfire cores configured with a data cache can't provide coherent
DMA allocations at all.

Instead of returning non-coherent kernel memory in this case,
return NULL and fail the allocation.

The only driver that used to rely on the previous behavior (fec) has
been switched to use non-coherent allocations for this case recently.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Tested-by: Greg Ungerer <gerg@linux-m68k.org>

diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 50ada24dfbbadf9b093a1ce006690075a3ea3be2..c1c0faffb0d4135f88c6c9dbdc21e53789719d4b 100644 (file)
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -6,7 +6,6 @@ config M68K
        select ARCH_HAS_BINFMT_FLAT
        select ARCH_HAS_CPU_FINALIZE_INIT if MMU
        select ARCH_HAS_CURRENT_STACK_POINTER
-       select ARCH_HAS_DMA_ALLOC if M68K_NONCOHERENT_DMA && COLDFIRE
        select ARCH_HAS_DMA_PREP_COHERENT if M68K_NONCOHERENT_DMA && !COLDFIRE
        select ARCH_HAS_SYNC_DMA_FOR_DEVICE if M68K_NONCOHERENT_DMA
        select ARCH_HAVE_NMI_SAFE_CMPXCHG if RMW_INSNS

diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c
index f83870cfa79b37fcb86c738d1cda1a13d8ee5024..eef63d032abb53e7b20afb4a23e9da741e13386a 100644 (file)
--- a/arch/m68k/kernel/dma.c
+++ b/arch/m68k/kernel/dma.c
@@ -33,29 +33,6 @@ pgprot_t pgprot_dmacoherent(pgprot_t prot)
        }
        return prot;
 }
-#else
-void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
-               gfp_t gfp, unsigned long attrs)
-{
-       void *ret;
-
-       if (dev == NULL || (*dev->dma_mask < 0xffffffff))
-               gfp |= GFP_DMA;
-       ret = (void *)__get_free_pages(gfp, get_order(size));
-
-       if (ret != NULL) {
-               memset(ret, 0, size);
-               *dma_handle = virt_to_phys(ret);
-       }
-       return ret;
-}
-
-void arch_dma_free(struct device *dev, size_t size, void *vaddr,
-               dma_addr_t dma_handle, unsigned long attrs)
-{
-       free_pages((unsigned long)vaddr, get_order(size));
-}
-
 #endif /* CONFIG_MMU && !CONFIG_COLDFIRE */
 
 void arch_sync_dma_for_device(phys_addr_t handle, size_t size,