[PATCH -mm] intel-iommu sg chaining support

FUJITA Tomonori
2007-09-29T12:17:24Z

x86_64 defines ARCH_HAS_SG_CHAIN. So if IOMMU implementations don't
support sg chaining, we will get data corruption.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
---
drivers/pci/intel-iommu.c | 32 ++++++++++++++++----------------
1 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index dab329f..4668995 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1963,7 +1963,7 @@ static void intel_free_coherent(struct device *hwdev, size_t size,
}

#define SG_ENT_VIRT_ADDRESS(sg) (page_address((sg)->page) + (sg)->offset)
-static void intel_unmap_sg(struct device *hwdev, struct scatterlist *sg,
+static void intel_unmap_sg(struct device *hwdev, struct scatterlist *sglist,
int nelems, int dir)
{
int i;
@@ -1973,16 +1973,17 @@ static void intel_unmap_sg(struct device *hwdev, struct scatterlist *sg,
struct iova *iova;
size_t size = 0;
void *addr;
+ struct scatterlist *sg;

if (pdev->sysdata == DUMMY_DEVICE_DOMAIN_INFO)
return;

domain = find_domain(pdev);

- iova = find_iova(&domain->iovad, IOVA_PFN(sg[0].dma_address));
+ iova = find_iova(&domain->iovad, IOVA_PFN(sglist[0].dma_address));
if (!iova)
return;
- for (i = 0; i < nelems; i++, sg++) {
+ for_each_sg(sglist, sg, nelems, i) {
addr = SG_ENT_VIRT_ADDRESS(sg);
size += aligned_size((u64)addr, sg->length);
}
@@ -2003,20 +2004,20 @@ static void intel_unmap_sg(struct device *hwdev, struct scatterlist *sg,
}

static int intel_nontranslate_map_sg(struct device *hddev,
- struct scatterlist *sg, int nelems, int dir)
+ struct scatterlist *sglist, int nelems, int dir)
{
int i;
+ struct scatterlist *sg;

- for (i = 0; i < nelems; i++) {
- struct scatterlist *s = &sg[i];
- BUG_ON(!s->page);
- s->dma_address = virt_to_bus(SG_ENT_VIRT_ADDRESS(s));
- s->dma_length = s->length;
+ for_each_sg(sglist, sg, nelems, i) {
+ BUG_ON(!sg->page);
+ sg->dma_address = virt_to_bus(SG_ENT_VIRT_ADDRESS(sg));
+ sg->dma_length = sg->length;
}
return nelems;
}

-static int intel_map_sg(struct device *hwdev, struct scatterlist *sg,
+static int intel_map_sg(struct device *hwdev, struct scatterlist *sglist,
int nelems, int dir)
{
void *addr;
@@ -2028,18 +2029,18 @@ static int intel_map_sg(struct device *hwdev, struct scatterlist *sg,
size_t offset = 0;
struct iova *iova = NULL;
int ret;
- struct scatterlist *orig_sg = sg;
+ struct scatterlist *sg;
unsigned long start_addr;

BUG_ON(dir == DMA_NONE);
if (pdev->sysdata == DUMMY_DEVICE_DOMAIN_INFO)
- return intel_nontranslate_map_sg(hwdev, sg, nelems, dir);
+ return intel_nontranslate_map_sg(hwdev, sglist, nelems, dir);

domain = get_valid_domain_for_dev(pdev);
if (!domain)
return 0;

- for (i = 0; i < nelems; i++, sg++) {
+ for_each_sg(sglist, sg, nelems, i) {
addr = SG_ENT_VIRT_ADDRESS(sg);
addr = (void *)virt_to_phys(addr);
size += aligned_size((u64)addr, sg->length);
@@ -2047,7 +2048,7 @@ static int intel_map_sg(struct device *hwdev, struct scatterlist *sg,

iova = __intel_alloc_iova(hwdev, domain, size);
if (!iova) {
- orig_sg->dma_length = 0;
+ sglist->dma_length = 0;
return 0;
}

@@ -2063,8 +2064,7 @@ static int intel_map_sg(struct device *hwdev, struct scatterlist *sg,

start_addr = iova->pfn_lo << PAGE_SHIFT_4K;
offset = 0;
- sg = orig_sg;
- for (i = 0; i < nelems; i++, sg++) {
+ for_each_sg(sglist, sg, nelems, i) {
addr = SG_ENT_VIRT_ADDRESS(sg);
addr = (void *)virt_to_phys(addr);
size = aligned_size((u64)addr, sg->length);
--
1.5.2.4