diff mbox series

[01/25] arm64/iommu: handle non-remapped addresses in ->mmap and ->get_sgtable

Message ID 20190430105214.24628-2-hch@lst.de (mailing list archive)
State New, archived
Headers show
Series [01/25] arm64/iommu: handle non-remapped addresses in ->mmap and ->get_sgtable | expand

Commit Message

Christoph Hellwig April 30, 2019, 10:51 a.m. UTC 
DMA allocations that can't sleep may return non-remapped addresses, but
we do not properly handle them in the mmap and get_sgtable methods.
Resolve non-vmalloc addresses using virt_to_page to handle this corner
case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
---
 arch/arm64/mm/dma-mapping.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

Comments

Catalin Marinas May 3, 2019, 11:33 a.m. UTC | #1 
On Tue, Apr 30, 2019 at 06:51:50AM -0400, Christoph Hellwig wrote:
> DMA allocations that can't sleep may return non-remapped addresses, but
> we do not properly handle them in the mmap and get_sgtable methods.
> Resolve non-vmalloc addresses using virt_to_page to handle this corner
> case.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Robin Murphy <robin.murphy@arm.com>

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Christoph Hellwig May 7, 2019, 6:37 a.m. UTC | #2 
On Fri, May 03, 2019 at 12:33:53PM +0100, Catalin Marinas wrote:
> On Tue, Apr 30, 2019 at 06:51:50AM -0400, Christoph Hellwig wrote:
> > DMA allocations that can't sleep may return non-remapped addresses, but
> > we do not properly handle them in the mmap and get_sgtable methods.
> > Resolve non-vmalloc addresses using virt_to_page to handle this corner
> > case.
> > 
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> > Reviewed-by: Robin Murphy <robin.murphy@arm.com>
> 
> Acked-by: Catalin Marinas <catalin.marinas@arm.com>

Given that this is a bug fix mostly separate from the rest of the
series - do you want to pick it up for 5.2 and maybe add a Cc for
stable?
Will Deacon May 7, 2019, 9:05 a.m. UTC | #3 
On Tue, May 07, 2019 at 08:37:20AM +0200, Christoph Hellwig wrote:
> On Fri, May 03, 2019 at 12:33:53PM +0100, Catalin Marinas wrote:
> > On Tue, Apr 30, 2019 at 06:51:50AM -0400, Christoph Hellwig wrote:
> > > DMA allocations that can't sleep may return non-remapped addresses, but
> > > we do not properly handle them in the mmap and get_sgtable methods.
> > > Resolve non-vmalloc addresses using virt_to_page to handle this corner
> > > case.
> > > 
> > > Signed-off-by: Christoph Hellwig <hch@lst.de>
> > > Reviewed-by: Robin Murphy <robin.murphy@arm.com>
> > 
> > Acked-by: Catalin Marinas <catalin.marinas@arm.com>
> 
> Given that this is a bug fix mostly separate from the rest of the
> series - do you want to pick it up for 5.2 and maybe add a Cc for
> stable?

Sure thing; I'll probably send it after -rc1 unless we get some other fixes
in during the merge window.

Will
diff mbox series

Patch

diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 78c0a72f822c..674860e3e478 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -249,6 +249,11 @@  static int __iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 	if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
 		return ret;
 
+	if (!is_vmalloc_addr(cpu_addr)) {
+		unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr));
+		return __swiotlb_mmap_pfn(vma, pfn, size);
+	}
+
 	if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) {
 		/*
 		 * DMA_ATTR_FORCE_CONTIGUOUS allocations are always remapped,
@@ -272,6 +277,11 @@  static int __iommu_get_sgtable(struct device *dev, struct sg_table *sgt,
 	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 	struct vm_struct *area = find_vm_area(cpu_addr);
 
+	if (!is_vmalloc_addr(cpu_addr)) {
+		struct page *page = virt_to_page(cpu_addr);
+		return __swiotlb_get_sgtable_page(sgt, page, size);
+	}
+
 	if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) {
 		/*
 		 * DMA_ATTR_FORCE_CONTIGUOUS allocations are always remapped,