[tip:x86/dma] x86/dma/amd_gart: Use dma_direct_{alloc,free}()

From: tip-bot for Christoph Hellwig
Date: Fri Mar 23 2018 - 15:51:13 EST


Commit-ID: 51c7eeba7975c1d2a02eefd00ece6de25176f5f3
Gitweb: https://git.kernel.org/tip/51c7eeba7975c1d2a02eefd00ece6de25176f5f3
Author: Christoph Hellwig <hch@xxxxxx>
AuthorDate: Mon, 19 Mar 2018 11:38:18 +0100
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Tue, 20 Mar 2018 10:01:57 +0100

x86/dma/amd_gart: Use dma_direct_{alloc,free}()

This gains support for CMA allocations for the force_iommu case, and
cleans up the code a bit.

Tested-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: Jon Mason <jdmason@xxxxxxxx>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Muli Ben-Yehuda <mulix@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20180319103826.12853-7-hch@xxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/kernel/amd_gart_64.c | 36 ++++++++++++++----------------------
1 file changed, 14 insertions(+), 22 deletions(-)

diff --git a/arch/x86/kernel/amd_gart_64.c b/arch/x86/kernel/amd_gart_64.c
index 79ac6caaaabb..f299d8a479bb 100644
--- a/arch/x86/kernel/amd_gart_64.c
+++ b/arch/x86/kernel/amd_gart_64.c
@@ -480,29 +480,21 @@ static void *
gart_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_addr,
gfp_t flag, unsigned long attrs)
{
- dma_addr_t paddr;
- unsigned long align_mask;
- struct page *page;
-
- if (force_iommu && dev->coherent_dma_mask > DMA_BIT_MASK(24)) {
- flag &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
- page = alloc_pages(flag | __GFP_ZERO, get_order(size));
- if (!page)
- return NULL;
-
- align_mask = (1UL << get_order(size)) - 1;
- paddr = dma_map_area(dev, page_to_phys(page), size,
- DMA_BIDIRECTIONAL, align_mask);
-
- flush_gart();
- if (paddr != bad_dma_addr) {
- *dma_addr = paddr;
- return page_address(page);
- }
- __free_pages(page, get_order(size));
- } else
- return dma_direct_alloc(dev, size, dma_addr, flag, attrs);
+ void *vaddr;
+
+ vaddr = dma_direct_alloc(dev, size, dma_addr, flag, attrs);
+ if (!vaddr ||
+ !force_iommu || dev->coherent_dma_mask <= DMA_BIT_MASK(24))
+ return vaddr;

+ *dma_addr = dma_map_area(dev, virt_to_phys(vaddr), size,
+ DMA_BIDIRECTIONAL, (1UL << get_order(size)) - 1);
+ flush_gart();
+ if (unlikely(*dma_addr == bad_dma_addr))
+ goto out_free;
+ return vaddr;
+out_free:
+ dma_direct_free(dev, size, vaddr, *dma_addr, attrs);
return NULL;
}