[PATCH v2 09/26] iommu/amd: Introduce domain for IOMMU Private Address (IPA) region

[Suravee Suthikulpanit]

AMD vIOMMU introduces the IOMMU Private Address (IPA) region, which is
used to manage data structures necessary for IOMMU virtualization within
the guest.

Introduce a new domain specifically for IPA region for each IOMMU, which
is stored in struct amd_iommu.viommu_pdom. This domain uses AMD IOMMU v1
page table.

For more info, please see section vIOMMU Private Address Space of the IOMMU
specification [1].

[1] https://docs.amd.com/v/u/en-US/48882_3.10_PUB

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
 drivers/iommu/amd/amd_iommu.h       |  5 +++++
 drivers/iommu/amd/amd_iommu_types.h |  3 +++
 drivers/iommu/amd/iommu.c           |  9 ++++----
 drivers/iommu/amd/viommu.c          | 35 +++++++++++++++++++++++++++++
 4 files changed, 47 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/amd/amd_iommu.h b/drivers/iommu/amd/amd_iommu.h
index 2ce207529ea0..1aa79a26a127 100644
--- a/drivers/iommu/amd/amd_iommu.h
+++ b/drivers/iommu/amd/amd_iommu.h
@@ -31,6 +31,7 @@ void *__init iommu_alloc_4k_pages(struct amd_iommu *iommu,
 				  gfp_t gfp, size_t size);
 u8 __iomem * __init iommu_map_mmio_space(u64 address, u64 end);
 void __init iommu_unmap_mmio_space(struct amd_iommu *iommu);
+int iommu_flush_dte(struct amd_iommu *iommu, u16 devid);
 
 #ifdef CONFIG_AMD_IOMMU_DEBUGFS
 void amd_iommu_debugfs_setup(void);
@@ -39,6 +40,8 @@ static inline void amd_iommu_debugfs_setup(void) {}
 #endif
 
 extern bool amd_iommu_viommu;
+extern const struct pt_iommu_driver_ops amd_hw_driver_ops_v1;
+extern const struct iommu_domain_ops amdv1_ops;
 
 /* Needed for interrupt remapping */
 int amd_iommu_prepare(void);
@@ -56,6 +59,8 @@ extern bool amd_iommu_hatdis;
 /* Protection domain ops */
 void amd_iommu_init_identity_domain(void);
 struct protection_domain *protection_domain_alloc(void);
+struct iommu_domain *amd_iommu_domain_alloc_paging_v1(struct device *dev,
+						      u32 flags);
 struct iommu_domain *amd_iommu_domain_alloc_sva(struct device *dev,
 						struct mm_struct *mm);
 void amd_iommu_domain_free(struct iommu_domain *dom);
diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h
index 44fa1d6c64d6..02d359f09148 100644
--- a/drivers/iommu/amd/amd_iommu_types.h
+++ b/drivers/iommu/amd/amd_iommu_types.h
@@ -814,6 +814,9 @@ struct amd_iommu {
 
 	struct ida gid_ida;		 /* guest IDs for this IOMMU */
 	bool gid_ida_inited;
+
+	/* HW vIOMMU support */
+	struct protection_domain *viommu_pdom;
 };
 
 static inline struct amd_iommu *dev_to_amd_iommu(struct device *dev)
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 6f5ecc48f4ad..d89664eba898 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -1551,7 +1551,7 @@ static void domain_flush_complete(struct protection_domain *domain)
 		amd_iommu_completion_wait(pdom_iommu_info->iommu);
 }
 
-static int iommu_flush_dte(struct amd_iommu *iommu, u16 devid)
+int iommu_flush_dte(struct amd_iommu *iommu, u16 devid)
 {
 	struct iommu_cmd cmd;
 
@@ -2726,12 +2726,12 @@ static void amd_iommu_iotlb_sync(struct iommu_domain *domain,
 	iommu_put_pages_list(&gather->freelist);
 }
 
-static const struct pt_iommu_driver_ops amd_hw_driver_ops_v1 = {
+const struct pt_iommu_driver_ops amd_hw_driver_ops_v1 = {
 	.get_top_lock = amd_iommu_get_top_lock,
 	.change_top = amd_iommu_change_top,
 };
 
-static const struct iommu_domain_ops amdv1_ops = {
+const struct iommu_domain_ops amdv1_ops = {
 	IOMMU_PT_DOMAIN_OPS(amdv1),
 	.iotlb_sync_map = amd_iommu_iotlb_sync_map,
 	.flush_iotlb_all = amd_iommu_flush_iotlb_all,
@@ -2746,8 +2746,7 @@ static const struct iommu_dirty_ops amdv1_dirty_ops = {
 	.set_dirty_tracking = amd_iommu_set_dirty_tracking,
 };
 
-static struct iommu_domain *amd_iommu_domain_alloc_paging_v1(struct device *dev,
-							     u32 flags)
+struct iommu_domain *amd_iommu_domain_alloc_paging_v1(struct device *dev, u32 flags)
 {
 	struct pt_iommu_amdv1_cfg cfg = {};
 	struct protection_domain *domain;
diff --git a/drivers/iommu/amd/viommu.c b/drivers/iommu/amd/viommu.c
index 9e6eb2f977ec..63360eef6b0d 100644
--- a/drivers/iommu/amd/viommu.c
+++ b/drivers/iommu/amd/viommu.c
@@ -131,6 +131,37 @@ static int __init viommu_vf_vfcntl_init(struct amd_iommu *iommu)
 	return -ENOMEM;
 }
 
+static int viommu_private_space_init(struct amd_iommu *iommu)
+{
+	struct iommu_domain *dom;
+	struct protection_domain *pdom;
+	struct pt_iommu_amdv1_hw_info pt_info;
+
+	/*
+	 * Setup page table root pointer, Guest MMIO and
+	 * Cmdbuf Dirty Status regions.
+	 */
+	dom = amd_iommu_domain_alloc_paging_v1(&iommu->dev->dev, 0);
+	if (!dom) {
+		pr_err("%s: Failed to initialize private space\n", __func__);
+		goto err_out;
+	}
+
+	pdom = to_pdomain(dom);
+	iommu->viommu_pdom = pdom;
+
+	pt_iommu_amdv1_hw_info(&pdom->amdv1, &pt_info);
+	pr_debug("%s: devid=%#x, pte_root=%#llx\n",
+		 __func__, iommu->devid,
+		 (unsigned long long)pt_info.host_pt_root);
+
+	return 0;
+err_out:
+	if (dom)
+		amd_iommu_domain_free(dom);
+	return -ENOMEM;
+}
+
 /*
  * Returns VF MMIO BAR offset for the give guest ID which will be
  * mapped to guest vIOMMU 3rd 4K MMIO address
@@ -160,5 +191,9 @@ int __init amd_viommu_init(struct amd_iommu *iommu)
 
 	amd_viommu_gid_ida_init(iommu);
 
+	ret = viommu_private_space_init(iommu);
+	if (ret)
+		return ret;
+
 	return 0;
 }
-- 
2.34.1