summaryrefslogtreecommitdiff
path: root/arch/x86/kernel
diff options
context:
space:
mode:
authorAlex Williamson <alex.williamson@redhat.com>2011-10-21 15:56:24 -0400
committerJoerg Roedel <joerg.roedel@amd.com>2011-11-15 12:22:31 +0100
commitbcb71abe7d4c5a0d0368c67da0a7def4fc73497a (patch)
tree3a043f872b234cb5c47cec1c01b4bbb69539fa0f /arch/x86/kernel
parent8fbdce659549d93dfb257ec4eabacf63a188e506 (diff)
iommu: Add option to group multi-function devices
The option iommu=group_mf indicates the that the iommu driver should expose all functions of a multi-function PCI device as the same iommu_device_group. This is useful for disallowing individual functions being exposed as independent devices to userspace as there are often hidden dependencies. Virtual functions are not affected by this option. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r--arch/x86/kernel/pci-dma.c11
1 files changed, 11 insertions, 0 deletions
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 80dc793b3f63..1c4d769e21ea 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -45,6 +45,15 @@ int iommu_detected __read_mostly = 0;
*/
int iommu_pass_through __read_mostly;
+/*
+ * Group multi-function PCI devices into a single device-group for the
+ * iommu_device_group interface. This tells the iommu driver to pretend
+ * it cannot distinguish between functions of a device, exposing only one
+ * group for the device. Useful for disallowing use of individual PCI
+ * functions from userspace drivers.
+ */
+int iommu_group_mf __read_mostly;
+
extern struct iommu_table_entry __iommu_table[], __iommu_table_end[];
/* Dummy device used for NULL arguments (normally ISA). */
@@ -169,6 +178,8 @@ static __init int iommu_setup(char *p)
#endif
if (!strncmp(p, "pt", 2))
iommu_pass_through = 1;
+ if (!strncmp(p, "group_mf", 8))
+ iommu_group_mf = 1;
gart_parse_options(p);