VServer 1.9.2 (patch-2.6.8.1-vs1.9.2.diff)

[linux-2.6.git] / arch / x86_64 / kernel / pci-gart.c

diff --git a/arch/x86_64/kernel/pci-gart.c b/arch/x86_64/kernel/pci-gart.c
index fd1c2d7..09fde74 100644 (file)
--- a/arch/x86_64/kernel/pci-gart.c
+++ b/arch/x86_64/kernel/pci-gart.c
@@ -70,6 +70,8 @@ int iommu_fullflush = 1;
 static spinlock_t iommu_bitmap_lock = SPIN_LOCK_UNLOCKED;
 static unsigned long *iommu_gart_bitmap; /* guarded by iommu_bitmap_lock */
 
+static u32 gart_unmapped_entry; 
+
 #define GPTE_VALID    1
 #define GPTE_COHERENT 2
 #define GPTE_ENCODE(x) \
@@ -147,8 +149,6 @@ static void free_iommu(unsigned long offset, int size)
 static void flush_gart(struct pci_dev *dev)
 { 
        unsigned long flags;
-       int bus = dev ? dev->bus->number : -1;
-       cpumask_const_t bus_cpumask = pcibus_to_cpumask(bus);
        int flushed = 0;
        int i;
 
@@ -158,8 +158,6 @@ static void flush_gart(struct pci_dev *dev)
                        u32 w;
                        if (!northbridges[i]) 
                                continue;
-                       if (bus >= 0 && !(cpu_isset_const(i, bus_cpumask)))
-                               continue;
                        pci_write_config_dword(northbridges[i], 0x9c, 
                                               northbridge_flush_word[i] | 1); 
                        /* Make sure the hardware actually executed the flush. */
@@ -169,7 +167,7 @@ static void flush_gart(struct pci_dev *dev)
                        flushed++;
                } 
                if (!flushed) 
-                       printk("nothing to flush? %d\n", bus);
+                       printk("nothing to flush?\n");
                need_flush = 0;
        } 
        spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
@@ -255,7 +253,7 @@ void pci_free_consistent(struct pci_dev *hwdev, size_t size,
 #define SET_LEAK(x) if (iommu_leak_tab) \
                        iommu_leak_tab[x] = __builtin_return_address(0);
 #define CLEAR_LEAK(x) if (iommu_leak_tab) \
-                       iommu_leak_tab[x] = 0;
+                       iommu_leak_tab[x] = NULL;
 
 /* Debugging aid for drivers that don't free their IOMMU tables */
 static void **iommu_leak_tab; 
@@ -479,6 +477,11 @@ int pci_map_sg(struct pci_dev *dev, struct scatterlist *sg, int nents, int dir)
        unsigned long pages = 0;
        int need = 0, nextneed;
 
+#ifdef CONFIG_SWIOTLB
+       if (swiotlb)
+               return swiotlb_map_sg(&dev->dev,sg,nents,dir);
+#endif
+
        BUG_ON(dir == PCI_DMA_NONE);
        if (nents == 0) 
                return 0;
@@ -562,7 +565,7 @@ void pci_unmap_single(struct pci_dev *hwdev, dma_addr_t dma_addr,
        iommu_page = (dma_addr - iommu_bus_base)>>PAGE_SHIFT;   
        npages = to_pages(dma_addr, size);
        for (i = 0; i < npages; i++) { 
-               iommu_gatt_base[iommu_page + i] = 0; 
+               iommu_gatt_base[iommu_page + i] = gart_unmapped_entry; 
                CLEAR_LEAK(iommu_page + i);
        }
        free_iommu(iommu_page, npages);
@@ -729,7 +732,8 @@ static int __init pci_iommu_init(void)
        unsigned long aper_size;
        unsigned long iommu_start;
        struct pci_dev *dev;
-               
+       unsigned long scratch;
+       long i;
 
 #ifndef CONFIG_AGP_AMD64
        no_agp = 1; 
@@ -766,7 +770,7 @@ static int __init pci_iommu_init(void)
                        return -1;
                }
        } 
-       
+
        aper_size = info.aper_size * 1024 * 1024;       
        iommu_size = check_iommu_size(info.aper_base, aper_size); 
        iommu_pages = iommu_size >> PAGE_SHIFT; 
@@ -815,6 +819,19 @@ static int __init pci_iommu_init(void)
         */
        clear_kernel_mapping((unsigned long)__va(iommu_bus_base), iommu_size);
 
+       /* 
+        * Try to workaround a bug (thanks to BenH) 
+        * Set unmapped entries to a scratch page instead of 0. 
+        * Any prefetches that hit unmapped entries won't get an bus abort
+        * then.
+        */
+       scratch = get_zeroed_page(GFP_KERNEL); 
+       if (!scratch) 
+               panic("Cannot allocate iommu scratch page");
+       gart_unmapped_entry = GPTE_ENCODE(__pa(scratch));
+       for (i = EMERGENCY_PAGES; i < iommu_pages; i++) 
+               iommu_gatt_base[i] = gart_unmapped_entry;
+
        for_all_nb(dev) {
                u32 flag; 
                int cpu = PCI_SLOT(dev->devfn) - 24;