x86: make GART to respect device's dma_mask about virtual mappings

Currently, GART IOMMU ingores device's dma_mask when it does virtual
mappings. So it could give a device a virtual address that the device
can't access to.

This patch fixes the above problem.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 28 insertions, 11 deletions

diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index 1b0c412566e5..9972c42ac925 100644
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -83,23 +83,34 @@ static unsigned long next_bit;  /* protected by iommu_bitmap_lock */
 static int need_flush;          /* global flush state. set for each gart wrap */
 
 static unsigned long alloc_iommu(struct device *dev, int size,
-                                 unsigned long align_mask)
+                                 unsigned long align_mask, u64 dma_mask)
 {
         unsigned long offset, flags;
         unsigned long boundary_size;
         unsigned long base_index;
+        unsigned long limit;
 
         base_index = ALIGN(iommu_bus_base & dma_get_seg_boundary(dev),
                            PAGE_SIZE) >> PAGE_SHIFT;
         boundary_size = ALIGN((unsigned long long)dma_get_seg_boundary(dev) + 1,
                               PAGE_SIZE) >> PAGE_SHIFT;
 
+        limit = iommu_device_max_index(iommu_pages,
+                                       DIV_ROUND_UP(iommu_bus_base, PAGE_SIZE),
+                                       dma_mask >> PAGE_SHIFT);
+
         spin_lock_irqsave(&iommu_bitmap_lock, flags);
-        offset = iommu_area_alloc(iommu_gart_bitmap, iommu_pages, next_bit,
+
+        if (limit <= next_bit) {
+                need_flush = 1;
+                next_bit = 0;
+        }
+
+        offset = iommu_area_alloc(iommu_gart_bitmap, limit, next_bit,
                                   size, base_index, boundary_size, align_mask);
-        if (offset == -1) {
+        if (offset == -1 && next_bit) {
                 need_flush = 1;
-                offset = iommu_area_alloc(iommu_gart_bitmap, iommu_pages, 0,
+                offset = iommu_area_alloc(iommu_gart_bitmap, limit, 0,
                                           size, base_index, boundary_size,
                                           align_mask);
         }
@@ -228,12 +239,14 @@ nonforced_iommu(struct device *dev, unsigned long addr, size_t size)
  * Caller needs to check if the iommu is needed and flush.
  */
 static dma_addr_t dma_map_area(struct device *dev, dma_addr_t phys_mem,
-                                size_t size, int dir, unsigned long align_mask)
+                               size_t size, int dir, unsigned long align_mask,
+                               u64 dma_mask)
 {
         unsigned long npages = iommu_num_pages(phys_mem, size);
-        unsigned long iommu_page = alloc_iommu(dev, npages, align_mask);
+        unsigned long iommu_page;
         int i;
 
+        iommu_page = alloc_iommu(dev, npages, align_mask, dma_mask);
         if (iommu_page == -1) {
                 if (!nonforced_iommu(dev, phys_mem, size))
                         return phys_mem;
@@ -263,7 +276,7 @@ gart_map_single(struct device *dev, phys_addr_t paddr, size_t size, int dir)
         if (!need_iommu(dev, paddr, size))
                 return paddr;
 
-        bus = dma_map_area(dev, paddr, size, dir, 0);
+        bus = dma_map_area(dev, paddr, size, dir, 0, dma_get_mask(dev));
         flush_gart();
 
         return bus;
@@ -314,6 +327,7 @@ static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg,
 {
         struct scatterlist *s;
         int i;
+        u64 dma_mask = dma_get_mask(dev);
 
 #ifdef CONFIG_IOMMU_DEBUG
         printk(KERN_DEBUG "dma_map_sg overflow\n");
@@ -323,7 +337,8 @@ static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg,
                 unsigned long addr = sg_phys(s);
 
                 if (nonforced_iommu(dev, addr, s->length)) {
-                        addr = dma_map_area(dev, addr, s->length, dir, 0);
+                        addr = dma_map_area(dev, addr, s->length, dir, 0,
+                                            dma_mask);
                         if (addr == bad_dma_address) {
                                 if (i > 0)
                                         gart_unmap_sg(dev, sg, i, dir);
@@ -345,14 +360,16 @@ static int __dma_map_cont(struct device *dev, struct scatterlist *start,
                           int nelems, struct scatterlist *sout,
                           unsigned long pages)
 {
-        unsigned long iommu_start = alloc_iommu(dev, pages, 0);
-        unsigned long iommu_page = iommu_start;
+        unsigned long iommu_start;
+        unsigned long iommu_page;
         struct scatterlist *s;
         int i;
 
+        iommu_start = alloc_iommu(dev, pages, 0, dma_get_mask(dev));
         if (iommu_start == -1)
                 return -1;
 
+        iommu_page = iommu_start;
         for_each_sg(start, s, nelems, i) {
                 unsigned long pages, addr;
                 unsigned long phys_addr = s->dma_address;
@@ -497,7 +514,7 @@ gart_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_addr,
         align_mask = (1UL << get_order(size)) - 1;
 
         *dma_addr = dma_map_area(dev, __pa(vaddr), size, DMA_BIDIRECTIONAL,
-                                 align_mask);
+                                 align_mask, dma_mask);
         flush_gart();
 
         if (*dma_addr != bad_dma_address)