[PATCH v3 4/6] vfio-iommufd: Make vfio_iommufd_emulated_bind() return iommufd_access ID

Yi Liu
2023-03-27T09:34:45Z

vfio device cdev needs to return iommufd_access ID to userspace if
bind_iommufd succeeds.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
drivers/iommu/iommufd/device.c | 4 +++-
drivers/iommu/iommufd/selftest.c | 3 ++-
drivers/vfio/iommufd.c | 2 +-
include/linux/iommufd.h | 2 +-
4 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index 6999a10b5496..25115d401d8f 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -426,6 +426,7 @@ void iommufd_access_destroy_object(struct iommufd_object *obj)
* @ioas_id: ID for a IOMMUFD_OBJ_IOAS
* @ops: Driver's ops to associate with the access
* @data: Opaque data to pass into ops functions
+ * @id: Output ID number to return to userspace for this access
*
* An iommufd_access allows a driver to read/write to the IOAS without using
* DMA. The underlying CPU memory can be accessed using the
@@ -435,7 +436,7 @@ void iommufd_access_destroy_object(struct iommufd_object *obj)
*/
struct iommufd_access *
iommufd_access_create(struct iommufd_ctx *ictx,
- const struct iommufd_access_ops *ops, void *data)
+ const struct iommufd_access_ops *ops, void *data, u32 *id)
{
struct iommufd_access *access;

@@ -460,6 +461,7 @@ iommufd_access_create(struct iommufd_ctx *ictx,
access->ictx = ictx;
iommufd_ctx_get(ictx);
iommufd_object_finalize(ictx, &access->obj);
+ *id = access->obj.id;
return access;
}
EXPORT_SYMBOL_NS_GPL(iommufd_access_create, IOMMUFD);
diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c
index 1e89e1a8c5f0..e6e04dceffe3 100644
--- a/drivers/iommu/iommufd/selftest.c
+++ b/drivers/iommu/iommufd/selftest.c
@@ -554,6 +554,7 @@ static int iommufd_test_create_access(struct iommufd_ucmd *ucmd,
struct iommu_test_cmd *cmd = ucmd->cmd;
struct selftest_access *staccess;
struct iommufd_access *access;
+ u32 id;
int fdno;
int rc;

@@ -575,7 +576,7 @@ static int iommufd_test_create_access(struct iommufd_ucmd *ucmd,
(flags & MOCK_FLAGS_ACCESS_CREATE_NEEDS_PIN_PAGES) ?
&selftest_access_ops_pin :
&selftest_access_ops,
- staccess);
+ staccess, &id);
if (IS_ERR(access)) {
rc = PTR_ERR(access);
goto out_put_fdno;
diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c
index 78e2486586d7..1ee558c0be25 100644
--- a/drivers/vfio/iommufd.c
+++ b/drivers/vfio/iommufd.c
@@ -142,7 +142,7 @@ int vfio_iommufd_emulated_bind(struct vfio_device *vdev,

lockdep_assert_held(&vdev->dev_set->lock);

- user = iommufd_access_create(ictx, &vfio_user_ops, vdev);
+ user = iommufd_access_create(ictx, &vfio_user_ops, vdev, out_device_id);
if (IS_ERR(user))
return PTR_ERR(user);
vdev->iommufd_access = user;
diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h
index 155d3630aedc..1129a36a74c4 100644
--- a/include/linux/iommufd.h
+++ b/include/linux/iommufd.h
@@ -41,7 +41,7 @@ enum {

struct iommufd_access *
iommufd_access_create(struct iommufd_ctx *ictx,
- const struct iommufd_access_ops *ops, void *data);
+ const struct iommufd_access_ops *ops, void *data, u32 *id);
void iommufd_access_destroy(struct iommufd_access *access);
int iommufd_access_attach(struct iommufd_access *access, u32 ioas_id);

--
2.34.1