[PATCH] Calgary: allow compiling Calgary in but not using it by default

This patch makes it possible to compile Calgary in but not use it by
default. In this mode, use 'iommu=calgary' to activate it.

Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
Signed-off-by: Andi Kleen <ak@suse.de>

1 files changed, 5 insertions, 0 deletions

diff --git a/arch/x86_64/kernel/pci-dma.c b/arch/x86_64/kernel/pci-dma.c
index f8d857453f8a..683b7a5c1ab3 100644
--- a/arch/x86_64/kernel/pci-dma.c
+++ b/arch/x86_64/kernel/pci-dma.c
@@ -296,6 +296,11 @@ __init int iommu_setup(char *p)
                 gart_parse_options(p);
 #endif
 
+#ifdef CONFIG_CALGARY_IOMMU
+                if (!strncmp(p, "calgary", 7))
+                        use_calgary = 1;
+#endif /* CONFIG_CALGARY_IOMMU */
+
                 p += strcspn(p, ",");
                 if (*p == ',')
                         ++p;