From 50020fb6324465e478d6c8cdbf3c695f0a60358d Mon Sep 17 00:00:00 2001
From: Joerg Roedel <joerg.roedel@amd.com>
Date: Wed, 2 Sep 2009 15:38:40 +0200
Subject: [PATCH] x86/amd-iommu: Introduce increase_address_space function
This function will be used to increase the address space
size of a protection domain.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
arch/x86/include/asm/amd_iommu_types.h | 4 ++++
arch/x86/kernel/amd_iommu.c | 27 ++++++++++++++++++++++++++
2 files changed, 31 insertions(+)
diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h
index 97f3d09d3be5..1b4b3d6c9f04 100644
--- a/arch/x86/include/asm/amd_iommu_types.h
+++ b/arch/x86/include/asm/amd_iommu_types.h
@@ -160,6 +160,10 @@
((1ULL << PM_LEVEL_SHIFT((x))) - 1): \
(0xffffffffffffffffULL))
#define PM_LEVEL_INDEX(x, a) (((a) >> PM_LEVEL_SHIFT((x))) & 0x1ffULL)
+#define PM_LEVEL_ENC(x) (((x) << 9) & 0xe00ULL)
+#define PM_LEVEL_PDE(x, a) ((a) | PM_LEVEL_ENC((x)) | \
+ IOMMU_PTE_P | IOMMU_PTE_IR | IOMMU_PTE_IW)
+
#define IOMMU_PTE_L2_INDEX(address) (((address) >> 30) & 0x1ffULL)
#define IOMMU_PTE_L1_INDEX(address) (((address) >> 21) & 0x1ffULL)
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 5eab6a84b9cc..fc97b51f0287 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -1324,6 +1324,33 @@ static void update_domain(struct protection_domain *domain)
domain->updated = false;
}
+/*
+ * This function is used to add another level to an IO page table. Adding
+ * another level increases the size of the address space by 9 bits to a size up
+ * to 64 bits.
+ */
+static bool increase_address_space(struct protection_domain *domain,
+ gfp_t gfp)
+{
+ u64 *pte;
+
+ if (domain->mode == PAGE_MODE_6_LEVEL)
+ /* address space already 64 bit large */
+ return false;
+
+ pte = (void *)get_zeroed_page(gfp);
+ if (!pte)
+ return false;
+
+ *pte = PM_LEVEL_PDE(domain->mode,
+ virt_to_phys(domain->pt_root));
+ domain->pt_root = pte;
+ domain->mode += 1;
+ domain->updated = true;
+
+ return true;
+}
+
/*
* If the pte_page is not yet allocated this function is called
*/
--
2.34.1