[PATCH 06/11] iommu/amd: Refactor helper function for attaching / detaching device

[Vasant Hegde <vasant.hegde@amd.com>]

From: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>

To use the new helper function for setting up GCR3 table.

If system is booted with V2 page table then setup default GCR3 with
domain GCR3 pointer. So that all devices in the domain uses same page
table for translation. Also return page table setup status from
do_attach() function.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Co-developed-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
---
 drivers/iommu/amd/iommu.c | 54 ++++++++++++++++++++++++++++++++++++---
 1 file changed, 50 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index cc42732820dd..4fed3fbe069e 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -1821,15 +1821,41 @@ static void clear_dte_entry(struct amd_iommu *iommu, u16 devid)
 	amd_iommu_apply_erratum_63(iommu, devid);
 }
 
-static void do_attach(struct iommu_dev_data *dev_data,
-		      struct protection_domain *domain)
+/*
+ * Note: This is currently used when booting w/ amd_iommu=pgtbl_v2
+ */
+static int default_gcr3_init(struct iommu_dev_data *dev_data)
+{
+	struct gcr3_tbl_info *gcr3_info = &dev_data->gcr3_info;
+
+	/* By default, GCR3 is set to support non-PASID devices. */
+	gcr3_info->giov = true;
+
+	/*
+	 * By default, setup GCR3 table to support MAX PASIDs
+	 * support by the IOMMU HW.
+	 */
+	return setup_gcr3_table(dev_data->domain, -1);
+}
+
+static inline void default_gcr3_destroy(struct iommu_dev_data *dev_data)
+{
+	struct gcr3_tbl_info *gcr3_info = &dev_data->gcr3_info;
+
+	gcr3_info->giov = false;
+	free_gcr3_table(dev_data->domain);
+}
+
+static int do_attach(struct iommu_dev_data *dev_data,
+		     struct protection_domain *domain)
 {
 	struct amd_iommu *iommu;
 	bool ats;
+	int ret = 0;
 
 	iommu = amd_iommu_rlookup_iommu(dev_data->dev);
 	if (!iommu)
-		return;
+		return -EINVAL;
 	ats   = dev_data->ats_enabled;
 
 	/* Update data structures */
@@ -1844,12 +1870,27 @@ static void do_attach(struct iommu_dev_data *dev_data,
 	domain->dev_iommu[iommu->index] += 1;
 	domain->dev_cnt                 += 1;
 
+	if (domain->pd_mode == PD_MODE_V2) {
+		ret = default_gcr3_init(dev_data);
+		if (ret)
+			return ret;
+
+		ret = __set_gcr3(dev_data, 0,
+				 iommu_virt_to_phys(domain->iop.pgd));
+		if (ret) {
+			default_gcr3_destroy(dev_data);
+			return ret;
+		}
+	}
+
 	/* Update device table */
 	set_dte_entry(iommu, dev_data->devid, domain,
 		      ats, dev_data->ppr);
 	clone_aliases(iommu, dev_data->dev);
 
 	device_flush_dte(dev_data);
+
+	return ret;
 }
 
 static void do_detach(struct iommu_dev_data *dev_data)
@@ -1861,6 +1902,11 @@ static void do_detach(struct iommu_dev_data *dev_data)
 	if (!iommu)
 		return;
 
+	if (domain->pd_mode == PD_MODE_V2) {
+		__clear_gcr3(dev_data, 0);
+		default_gcr3_destroy(dev_data);
+	}
+
 	/* Update data structures */
 	dev_data->domain = NULL;
 	list_del(&dev_data->list);
@@ -1906,7 +1952,7 @@ static int attach_device(struct device *dev,
 	if (dev_is_pci(dev))
 		pdev_enable_caps(to_pci_dev(dev));
 
-	do_attach(dev_data, domain);
+	ret = do_attach(dev_data, domain);
 
 	/*
 	 * We might boot into a crash-kernel here. The crashed kernel
-- 
2.31.1