AMD IOMMU: add device reference counting for protection domains

Impact: know how many devices are assigned to a domain

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h
index 4862a5b..1c769f4 100644 (file)
--- 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 5c465c9..8b45bc4 100644 (file)
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -825,9 +825,10 @@ 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;