[PATCH 16/24] iommu/amd: Introduce IOMMUFD vDevice support for AMD

[Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>]

Initialize vDevice for AMD vIOMMU by setting up the Device ID Mapping
table using the guest device ID.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
 drivers/iommu/amd/amd_iommu_types.h | 10 ++++++++++
 drivers/iommu/amd/iommufd.c         | 31 +++++++++++++++++++++++++++++
 drivers/iommu/amd/nested.c          | 27 ++++++++++++++++++++++---
 3 files changed, 65 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h
index 03346258e2dc..39aa872c2741 100644
--- a/drivers/iommu/amd/amd_iommu_types.h
+++ b/drivers/iommu/amd/amd_iommu_types.h
@@ -388,6 +388,11 @@
 #define DTE_GPT_LEVEL_SHIFT	54
 #define DTE_GPT_LEVEL_MASK	GENMASK_ULL(55, 54)
 
+/* vIOMMU bit fields */
+#define DTE_VIOMMU_EN_SHIFT		15
+#define DTE_VIOMMU_GDEVICEID_MASK	GENMASK_ULL(31, 16)
+#define DTE_VIOMMU_GUESTID_MASK		GENMASK_ULL(47, 32)
+
 #define GCR3_VALID		0x01ULL
 
 /* DTE[128:179] | DTE[184:191] */
@@ -895,6 +900,7 @@ struct iommu_dev_data {
 	bool defer_attach;
 
 	struct ratelimit_state rs;        /* Ratelimit IOPF messages */
+
 };
 
 /* Map HPET and IOAPIC ids to the devid used by the IOMMU */
@@ -1122,6 +1128,10 @@ struct amd_irte_ops {
 	void (*clear_allocated)(struct irq_remap_table *, int);
 };
 
+struct amd_iommu_vdevice {
+	struct iommufd_vdevice core;
+};
+
 #ifdef CONFIG_IRQ_REMAP
 extern struct amd_irte_ops irte_32_ops;
 extern struct amd_irte_ops irte_128_ops;
diff --git a/drivers/iommu/amd/iommufd.c b/drivers/iommu/amd/iommufd.c
index bfc4b0ec22a9..1975b2932107 100644
--- a/drivers/iommu/amd/iommufd.c
+++ b/drivers/iommu/amd/iommufd.c
@@ -9,6 +9,7 @@
 #include "amd_iommu.h"
 #include "amd_viommu.h"
 #include "amd_iommu_types.h"
+#include "../iommufd/iommufd_private.h"
 
 static const struct iommufd_viommu_ops amd_viommu_ops;
 
@@ -126,6 +127,34 @@ static void amd_iommufd_viommu_destroy(struct iommufd_viommu *viommu)
 	amd_iommu_gid_free(iommu, aviommu->gid);
 }
 
+/*
+ * Called from drivers/iommu/iommufd/viommu.c: iommufd_vdevice_alloc_ioctl()
+ */
+static int _amd_viommu_vdevice_init(struct iommufd_vdevice *vdev)
+{
+	struct iommu_dev_data *dev_data;
+	struct pci_dev *pdev = to_pci_dev(vdev->idev->dev);
+	struct iommufd_viommu *viommu = vdev->viommu;
+	struct amd_iommu_viommu *aviommu = container_of(viommu, struct amd_iommu_viommu, core);
+
+	if (!pdev) {
+		pr_err("%s: not a PCI device\n", __func__);
+		return -EINVAL;
+	}
+
+	dev_data = dev_iommu_priv_get(&pdev->dev);
+	if (!dev_data) {
+		pr_err("%s: Device not found (devid=%#x)\n",
+		       __func__, pci_dev_id(pdev));
+		return -EINVAL;
+	}
+
+	pr_debug("%s: gid=%#x, hdev_id=%#x, gdev_id=%#llx\n", __func__,
+		 aviommu->gid, pci_dev_id(pdev), vdev->virt_id);
+
+	return 0;
+}
+
 /*
  * See include/linux/iommufd.h
  * struct iommufd_viommu_ops - vIOMMU specific operations
@@ -133,4 +162,6 @@ static void amd_iommufd_viommu_destroy(struct iommufd_viommu *viommu)
 static const struct iommufd_viommu_ops amd_viommu_ops = {
 	.alloc_domain_nested = amd_iommu_alloc_domain_nested,
 	.destroy = amd_iommufd_viommu_destroy,
+	.vdevice_size = VDEVICE_STRUCT_SIZE(struct amd_iommu_vdevice, core),
+	.vdevice_init = _amd_viommu_vdevice_init,
 };
diff --git a/drivers/iommu/amd/nested.c b/drivers/iommu/amd/nested.c
index 81a5ae00225e..6f3ae2496160 100644
--- a/drivers/iommu/amd/nested.c
+++ b/drivers/iommu/amd/nested.c
@@ -10,6 +10,7 @@
 #include <uapi/linux/iommufd.h>
 
 #include "amd_iommu.h"
+#include "amd_viommu.h"
 
 static const struct iommu_domain_ops nested_domain_ops;
 
@@ -183,13 +184,16 @@ amd_iommu_alloc_domain_nested(struct iommufd_viommu *viommu, u32 flags,
 	return ERR_PTR(ret);
 }
 
-static void set_dte_nested(struct amd_iommu *iommu, struct iommu_domain *dom,
-			   struct iommu_dev_data *dev_data, struct dev_table_entry *new)
+static int set_dte_nested(struct amd_iommu *iommu, struct iommu_domain *dom,
+			  struct iommu_dev_data *dev_data, struct dev_table_entry *new)
 {
+	int ret;
+	u16 gid;
 	struct protection_domain *parent;
 	struct nested_domain *ndom = to_ndomain(dom);
 	struct iommu_hwpt_amd_guest *gdte = &ndom->gdte;
 	struct pt_iommu_amdv1_hw_info pt_info;
+	unsigned long gDevId;
 
 	/*
 	 * The nest parent domain is attached during the call to the
@@ -197,9 +201,15 @@ static void set_dte_nested(struct amd_iommu *iommu, struct iommu_domain *dom,
 	 * of the struct amd_iommu_viommu.parent.
 	 */
 	if (WARN_ON(!ndom->viommu || !ndom->viommu->parent))
-		return;
+		return -EINVAL;
 
+	gid = ndom->viommu->gid;
 	parent = ndom->viommu->parent;
+
+	ret = iommufd_viommu_get_vdev_id(&ndom->viommu->core, dev_data->dev, &gDevId);
+	if (ret)
+		return ret;
+
 	amd_iommu_make_clear_dte(iommu, dev_data->devid, new);
 
 	/* Retrieve the current pagetable info via the IOMMU PT API. */
@@ -227,6 +237,17 @@ static void set_dte_nested(struct amd_iommu *iommu, struct iommu_domain *dom,
 
 	/* Guest paging mode */
 	new->data[2] |= gdte->dte[2] & DTE_GPT_LEVEL_MASK;
+
+	/* vImuEn */
+	new->data[3] |= 1ULL << DTE_VIOMMU_EN_SHIFT;
+
+	/* GDeviceID */
+	new->data[3] |= FIELD_PREP(DTE_VIOMMU_GDEVICEID_MASK, (u16)gDevId);
+
+	/* GuestID */
+	new->data[3] |= FIELD_PREP(DTE_VIOMMU_GUESTID_MASK, gid);
+
+	return 0;
 }
 
 static int nested_attach_device(struct iommu_domain *dom, struct device *dev,
-- 
2.34.1