x86/dma: Remove dma_alloc_coherent_mask()

These days all devices (including the ISA fallback device) have a coherent
DMA mask set, so remove the workaround.

Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jon Mason <jdmason@kudzu.us>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Muli Ben-Yehuda <mulix@mulix.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: iommu@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/20180319103826.12853-3-hch@lst.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 1 insertions, 15 deletions

diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 5bb72d3f8337..e1c60899fdbc 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -53,20 +53,6 @@
  * API.
  */
 
-#ifndef CONFIG_X86
-static unsigned long dma_alloc_coherent_mask(struct device *dev,
-                                            gfp_t gfp)
-{
-        unsigned long dma_mask = 0;
-
-        dma_mask = dev->coherent_dma_mask;
-        if (!dma_mask)
-                dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
-
-        return dma_mask;
-}
-#endif
-
 #define XEN_SWIOTLB_ERROR_CODE  (~(dma_addr_t)0x0)
 
 static char *xen_io_tlb_start, *xen_io_tlb_end;
@@ -328,7 +314,7 @@ xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
                 return ret;
 
         if (hwdev && hwdev->coherent_dma_mask)
-                dma_mask = dma_alloc_coherent_mask(hwdev, flags);
+                dma_mask = hwdev->coherent_dma_mask;
 
         /* At this point dma_handle is the physical address, next we are
          * going to set it to the machine address.