[PATCH 6.4 279/800] iommu/virtio: Detach domain on endpoint release

Greg Kroah-Hartman
2023-07-16T20:07:35Z

From: Jean-Philippe Brucker <jean-philippe@linaro.org>

[ Upstream commit 809d0810e3520da669d231303608cdf5fe5c1a70 ]

When an endpoint is released, for example a PCIe VF being destroyed or a
function hot-unplugged, it should be detached from its domain. Send a
DETACH request.

Fixes: edcd69ab9a32 ("iommu: Add virtio-iommu driver")
Reported-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Link: https://lore.kernel.org/all/15bf1b00-3aa0-973a-3a86-3fa5c4d41d2c@daynix.com/
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Tested-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Link: https://lore.kernel.org/r/20230515113946.1017624-2-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iommu/virtio-iommu.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)

diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 5b8fe9bfa9a5b..fd316a37d7562 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -788,6 +788,29 @@ static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev)
return 0;
}

+static void viommu_detach_dev(struct viommu_endpoint *vdev)
+{
+ int i;
+ struct virtio_iommu_req_detach req;
+ struct viommu_domain *vdomain = vdev->vdomain;
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(vdev->dev);
+
+ if (!vdomain)
+ return;
+
+ req = (struct virtio_iommu_req_detach) {
+ .head.type = VIRTIO_IOMMU_T_DETACH,
+ .domain = cpu_to_le32(vdomain->id),
+ };
+
+ for (i = 0; i < fwspec->num_ids; i++) {
+ req.endpoint = cpu_to_le32(fwspec->ids[i]);
+ WARN_ON(viommu_send_req_sync(vdev->viommu, &req, sizeof(req)));
+ }
+ vdomain->nr_endpoints--;
+ vdev->vdomain = NULL;
+}
+
static int viommu_map_pages(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t pgsize, size_t pgcount,
int prot, gfp_t gfp, size_t *mapped)
@@ -990,6 +1013,7 @@ static void viommu_release_device(struct device *dev)
{
struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);

+ viommu_detach_dev(vdev);
iommu_put_resv_regions(dev, &vdev->resv_regions);
kfree(vdev);
}
--
2.39.2