dma-direct: make uncached_kernel_address more general

Rename the symbol to arch_dma_set_uncached, and pass a size to it as
well as allow an error return.  That will allow reusing this hook for
in-place pagetable remapping.

As the in-place remap doesn't always require an explicit cache flush,
also detangle ARCH_HAS_DMA_PREP_COHERENT from ARCH_HAS_DMA_SET_UNCACHED.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>

2 files changed, 2 insertions, 2 deletions

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 32ee759a3fda..de229424b659 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -6,7 +6,7 @@ config XTENSA
 	select ARCH_HAS_DMA_PREP_COHERENT if MMU
 	select ARCH_HAS_SYNC_DMA_FOR_CPU if MMU
 	select ARCH_HAS_SYNC_DMA_FOR_DEVICE if MMU
-	select ARCH_HAS_UNCACHED_SEGMENT if MMU
+	select ARCH_HAS_DMA_SET_UNCACHED if MMU
 	select ARCH_USE_QUEUED_RWLOCKS
 	select ARCH_USE_QUEUED_SPINLOCKS
 	select ARCH_WANT_FRAME_POINTERS
diff --git a/arch/xtensa/kernel/pci-dma.c b/arch/xtensa/kernel/pci-dma.c
index 6a685545d5c9..17c4384f8495 100644
--- a/arch/xtensa/kernel/pci-dma.c
+++ b/arch/xtensa/kernel/pci-dma.c
@@ -92,7 +92,7 @@ void arch_dma_prep_coherent(struct page *page, size_t size)
  * coherent DMA memory operations when CONFIG_MMU is not enabled.
  */
 #ifdef CONFIG_MMU
-void *uncached_kernel_address(void *p)
+void *arch_dma_set_uncached(void *p, size_t size)
 {
 	return p + XCHAL_KSEG_BYPASS_VADDR - XCHAL_KSEG_CACHED_VADDR;
 }