From cf5f86a7d47df149857ba2fb72f9c6c9da46af2e Mon Sep 17 00:00:00 2001

From: Dave Jiang <dave.jiang@intel.com>

Date: Tue, 20 Apr 2021 11:46:46 -0700

Subject: [PATCH] dmaengine: idxd: enable SVA feature for IOMMU

Git-commit: cf5f86a7d47df149857ba2fb72f9c6c9da46af2e

Patch-mainline: v5.13-rc1

References: bsc#1192931

Enable IOMMU_DEV_FEAT_SVA before attempt to bind pasid. This is needed

according to iommu_sva_bind_device() comment. Currently Intel IOMMU code

does this before bind call. It really needs to be controlled by the driver.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Link: https://lore.kernel.org/r/161894440621.3202472.17644507396206848134.stgit@djiang5-desk3.ch.intel.com

Signed-off-by: Vinod Koul <vkoul@kernel.org>

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 drivers/dma/idxd/init.c |   19 ++++++++++++++-----

 1 file changed, 14 insertions(+), 5 deletions(-)

--- a/drivers/dma/idxd/init.c

+++ b/drivers/dma/idxd/init.c

@@ -328,11 +328,18 @@ static int idxd_probe(struct idxd_device

 	dev_dbg(dev, "IDXD reset complete\n");

 	if (IS_ENABLED(CONFIG_INTEL_IDXD_SVM) && sva) {

-		rc = idxd_enable_system_pasid(idxd);

-		if (rc < 0)

-			dev_warn(dev, "Failed to enable PASID. No SVA support: %d\n", rc);

-		else

-			set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags);

+		rc = iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA);

+		if (rc == 0) {

+			rc = idxd_enable_system_pasid(idxd);

+			if (rc < 0) {

+				iommu_dev_disable_feature(dev, IOMMU_DEV_FEAT_SVA);

+				dev_warn(dev, "Failed to enable PASID. No SVA support: %d\n", rc);

+			} else {

+				set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags);

+			}

+		} else {

+			dev_warn(dev, "Unable to turn on SVA feature.\n");

+		}

 	} else if (!sva) {

 		dev_warn(dev, "User forced SVA off via module param.\n");

 	}

@@ -369,6 +376,7 @@ static int idxd_probe(struct idxd_device

  err_setup:

 	if (device_pasid_enabled(idxd))

 		idxd_disable_system_pasid(idxd);

+	iommu_dev_disable_feature(dev, IOMMU_DEV_FEAT_SVA);

 	return rc;

 }

@@ -523,6 +531,7 @@ static void idxd_remove(struct pci_dev *

 	mutex_lock(&idxd_idr_lock);

 	idr_remove(&idxd_idrs[idxd->type], idxd->id);

 	mutex_unlock(&idxd_idr_lock);

+	iommu_dev_disable_feature(&pdev->dev, IOMMU_DEV_FEAT_SVA);

 }

 static struct pci_driver idxd_pci_driver = {