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Diffstat (limited to 'arch/x86/kernel/pci-dma.c')
-rw-r--r--arch/x86/kernel/pci-dma.c13
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 0a1408abcc6..d2f2c0158dc 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -16,6 +16,15 @@ EXPORT_SYMBOL(dma_ops);
static int iommu_sac_force __read_mostly;
+/*
+ * If this is disabled the IOMMU will use an optimized flushing strategy
+ * of only flushing when an mapping is reused. With it true the GART is
+ * flushed for every mapping. Problem is that doing the lazy flush seems
+ * to trigger bugs with some popular PCI cards, in particular 3ware (but
+ * has been also also seen with Qlogic at least).
+ */
+int iommu_fullflush;
+
#ifdef CONFIG_IOMMU_DEBUG
int panic_on_overflow __read_mostly = 1;
int force_iommu __read_mostly = 1;
@@ -171,6 +180,10 @@ static __init int iommu_setup(char *p)
}
if (!strncmp(p, "nomerge", 7))
iommu_merge = 0;
+ if (!strncmp(p, "fullflush", 8))
+ iommu_fullflush = 1;
+ if (!strncmp(p, "nofullflush", 11))
+ iommu_fullflush = 0;
if (!strncmp(p, "forcesac", 8))
iommu_sac_force = 1;
if (!strncmp(p, "allowdac", 8))