[PATCH 11/19] AMD IOMMU: add device reference counting for protection domains

Joerg Roedel
2008-12-04T17:39:09Z

Impact: know how many devices are assigned to a domain

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
arch/x86/include/asm/amd_iommu_types.h | 1 +
arch/x86/kernel/amd_iommu.c | 3 ++-
2 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h
index b74d35f..90f77de 100644
--- a/arch/x86/include/asm/amd_iommu_types.h
+++ b/arch/x86/include/asm/amd_iommu_types.h
@@ -203,6 +203,7 @@ struct protection_domain {
int mode; /* paging mode (0-6 levels) */
u64 *pt_root; /* page table root pointer */
unsigned long flags; /* flags to find out type of domain */
+ unsigned dev_cnt; /* devices assigned to this domain */
void *priv; /* private data */
};

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index be626ad..afd2128 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -819,9 +819,10 @@ static void set_device_domain(struct amd_iommu *iommu,
u16 devid)
{
unsigned long flags;
-
u64 pte_root = virt_to_phys(domain->pt_root);

+ domain->dev_cnt += 1;
+
pte_root |= (domain->mode & DEV_ENTRY_MODE_MASK)
<< DEV_ENTRY_MODE_SHIFT;
pte_root |= IOMMU_PTE_IR | IOMMU_PTE_IW | IOMMU_PTE_P | IOMMU_PTE_TV;
--
1.5.6.4