[PATCH 05/31] x86/pci-calgary: handle page-less SG entries
From: Christoph Hellwig <hch@lst.de>
Date: 2015-08-12 07:09:12
Also in:
linux-alpha, linux-arch, linux-media, linux-mips, linuxppc-dev, lkml, sparclinux
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
For the iommu offset we just need and offset into the page. Calculate that using the physical address instead of using the virtual address so that we don't require a virtual mapping. Signed-off-by: Christoph Hellwig <hch@lst.de> --- arch/x86/kernel/pci-calgary_64.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kernel/pci-calgary_64.c b/arch/x86/kernel/pci-calgary_64.c
index 0497f71..8f1581d 100644
--- a/arch/x86/kernel/pci-calgary_64.c
+++ b/arch/x86/kernel/pci-calgary_64.c@@ -368,16 +368,14 @@ static int calgary_map_sg(struct device *dev, struct scatterlist *sg, { struct iommu_table *tbl = find_iommu_table(dev); struct scatterlist *s; - unsigned long vaddr; + unsigned long paddr; unsigned int npages; unsigned long entry; int i; for_each_sg(sg, s, nelems, i) { - BUG_ON(!sg_page(s)); - - vaddr = (unsigned long) sg_virt(s); - npages = iommu_num_pages(vaddr, s->length, PAGE_SIZE); + paddr = sg_phys(s); + npages = iommu_num_pages(paddr, s->length, PAGE_SIZE); entry = iommu_range_alloc(dev, tbl, npages); if (entry == DMA_ERROR_CODE) {
@@ -389,7 +387,7 @@ static int calgary_map_sg(struct device *dev, struct scatterlist *sg, s->dma_address = (entry << PAGE_SHIFT) | s->offset; /* insert into HW table */ - tce_build(tbl, entry, npages, vaddr & PAGE_MASK, dir); + tce_build(tbl, entry, npages, paddr & PAGE_MASK, dir); s->dma_length = s->length; }
--
1.9.1