diff mbox series

[v7,15/22] vfio-iommufd: Add detach_ioas support for physical VFIO devices

Message ID 20230316125534.17216-16-yi.l.liu@intel.com (mailing list archive)
State New, archived
Headers show
Series Add vfio_device cdev for iommufd support | expand

Commit Message

Yi Liu March 16, 2023, 12:55 p.m. UTC
this prepares for adding DETACH ioctl for physical VFIO devices.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 Documentation/driver-api/vfio.rst             |  8 +++++---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c             |  1 +
 drivers/vfio/iommufd.c                        | 20 +++++++++++++++++++
 .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c    |  2 ++
 drivers/vfio/pci/mlx5/main.c                  |  1 +
 drivers/vfio/pci/vfio_pci.c                   |  1 +
 drivers/vfio/platform/vfio_amba.c             |  1 +
 drivers/vfio/platform/vfio_platform.c         |  1 +
 drivers/vfio/vfio_main.c                      |  3 ++-
 include/linux/vfio.h                          |  8 +++++++-
 10 files changed, 41 insertions(+), 5 deletions(-)

Comments

Tian, Kevin March 17, 2023, 2:13 a.m. UTC | #1
> From: Liu, Yi L <yi.l.liu@intel.com>
> Sent: Thursday, March 16, 2023 8:55 PM
> 
> +void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev)
> +{
> +	lockdep_assert_held(&vdev->dev_set->lock);
> +
> +	if (WARN_ON(!vdev->iommufd_device) || !vdev->iommufd_attached)
> +		return;
> +

the 2nd check shouldn't be a WARN_ON. It's user-triggerable.
Yi Liu March 17, 2023, 3:06 a.m. UTC | #2
> From: Tian, Kevin <kevin.tian@intel.com>
> Sent: Friday, March 17, 2023 10:14 AM
> 
> > From: Liu, Yi L <yi.l.liu@intel.com>
> > Sent: Thursday, March 16, 2023 8:55 PM
> >
> > +void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev)
> > +{
> > +	lockdep_assert_held(&vdev->dev_set->lock);
> > +
> > +	if (WARN_ON(!vdev->iommufd_device) || !vdev->iommufd_attached)
> > +		return;
> > +
> 
> the 2nd check shouldn't be a WARN_ON. It's user-triggerable.

Yes. it has already been removed in this version.:)
Tian, Kevin March 17, 2023, 3:17 a.m. UTC | #3
> From: Liu, Yi L <yi.l.liu@intel.com>
> Sent: Friday, March 17, 2023 11:07 AM
> 
> > From: Tian, Kevin <kevin.tian@intel.com>
> > Sent: Friday, March 17, 2023 10:14 AM
> >
> > > From: Liu, Yi L <yi.l.liu@intel.com>
> > > Sent: Thursday, March 16, 2023 8:55 PM
> > >
> > > +void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev)
> > > +{
> > > +	lockdep_assert_held(&vdev->dev_set->lock);
> > > +
> > > +	if (WARN_ON(!vdev->iommufd_device) || !vdev->iommufd_attached)
> > > +		return;
> > > +
> >
> > the 2nd check shouldn't be a WARN_ON. It's user-triggerable.
> 
> Yes. it has already been removed in this version.:)

Huh, bad eyes. 
diff mbox series

Patch

diff --git a/Documentation/driver-api/vfio.rst b/Documentation/driver-api/vfio.rst
index 68abc089d6dd..363e12c90b87 100644
--- a/Documentation/driver-api/vfio.rst
+++ b/Documentation/driver-api/vfio.rst
@@ -279,6 +279,7 @@  similar to a file operations structure::
 					struct iommufd_ctx *ictx, u32 *out_device_id);
 		void	(*unbind_iommufd)(struct vfio_device *vdev);
 		int	(*attach_ioas)(struct vfio_device *vdev, u32 *pt_id);
+		void	(*detach_ioas)(struct vfio_device *vdev);
 		int	(*open_device)(struct vfio_device *vdev);
 		void	(*close_device)(struct vfio_device *vdev);
 		ssize_t	(*read)(struct vfio_device *vdev, char __user *buf,
@@ -315,9 +316,10 @@  container_of().
 	- The [un]bind_iommufd callbacks are issued when the device is bound to
 	  and unbound from iommufd.
 
-	- The attach_ioas callback is issued when the device is attached to an
-	  IOAS managed by the bound iommufd. The attached IOAS is automatically
-	  detached when the device is unbound from iommufd.
+	- The [de]attach_ioas callback is issued when the device is attached to
+	  and detached from an IOAS managed by the bound iommufd. However, the
+	  attached IOAS can also be automatically detached when the device is
+	  unbound from iommufd.
 
 	- The read/write/mmap callbacks implement the device region access defined
 	  by the device's own VFIO_DEVICE_GET_REGION_INFO ioctl.
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index c89a047a4cd8..d540cf683d93 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -594,6 +594,7 @@  static const struct vfio_device_ops vfio_fsl_mc_ops = {
 	.bind_iommufd	= vfio_iommufd_physical_bind,
 	.unbind_iommufd	= vfio_iommufd_physical_unbind,
 	.attach_ioas	= vfio_iommufd_physical_attach_ioas,
+	.detach_ioas	= vfio_iommufd_physical_detach_ioas,
 };
 
 static struct fsl_mc_driver vfio_fsl_mc_driver = {
diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c
index 32a3a57ebb34..563818340a18 100644
--- a/drivers/vfio/iommufd.c
+++ b/drivers/vfio/iommufd.c
@@ -107,6 +107,14 @@  int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id)
 {
 	int rc;
 
+	lockdep_assert_held(&vdev->dev_set->lock);
+
+	if (WARN_ON(!vdev->iommufd_device))
+		return -EINVAL;
+
+	if (vdev->iommufd_attached)
+		return -EBUSY;
+
 	rc = iommufd_device_attach(vdev->iommufd_device, pt_id);
 	if (rc)
 		return rc;
@@ -115,6 +123,18 @@  int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id)
 }
 EXPORT_SYMBOL_GPL(vfio_iommufd_physical_attach_ioas);
 
+void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev)
+{
+	lockdep_assert_held(&vdev->dev_set->lock);
+
+	if (WARN_ON(!vdev->iommufd_device) || !vdev->iommufd_attached)
+		return;
+
+	iommufd_device_detach(vdev->iommufd_device);
+	vdev->iommufd_attached = false;
+}
+EXPORT_SYMBOL_GPL(vfio_iommufd_physical_detach_ioas);
+
 /*
  * The emulated standard ops mean that vfio_device is going to use the
  * "mdev path" and will call vfio_pin_pages()/vfio_dma_rw(). Drivers using this
diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index a117eaf21c14..b2f9778c8366 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
@@ -1373,6 +1373,7 @@  static const struct vfio_device_ops hisi_acc_vfio_pci_migrn_ops = {
 	.bind_iommufd = vfio_iommufd_physical_bind,
 	.unbind_iommufd = vfio_iommufd_physical_unbind,
 	.attach_ioas = vfio_iommufd_physical_attach_ioas,
+	.detach_ioas = vfio_iommufd_physical_detach_ioas,
 };
 
 static const struct vfio_device_ops hisi_acc_vfio_pci_ops = {
@@ -1391,6 +1392,7 @@  static const struct vfio_device_ops hisi_acc_vfio_pci_ops = {
 	.bind_iommufd = vfio_iommufd_physical_bind,
 	.unbind_iommufd = vfio_iommufd_physical_unbind,
 	.attach_ioas = vfio_iommufd_physical_attach_ioas,
+	.detach_ioas = vfio_iommufd_physical_detach_ioas,
 };
 
 static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
diff --git a/drivers/vfio/pci/mlx5/main.c b/drivers/vfio/pci/mlx5/main.c
index e897537a9e8a..6fc3410989eb 100644
--- a/drivers/vfio/pci/mlx5/main.c
+++ b/drivers/vfio/pci/mlx5/main.c
@@ -1326,6 +1326,7 @@  static const struct vfio_device_ops mlx5vf_pci_ops = {
 	.bind_iommufd = vfio_iommufd_physical_bind,
 	.unbind_iommufd = vfio_iommufd_physical_unbind,
 	.attach_ioas = vfio_iommufd_physical_attach_ioas,
+	.detach_ioas = vfio_iommufd_physical_detach_ioas,
 };
 
 static int mlx5vf_pci_probe(struct pci_dev *pdev,
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 29091ee2e984..cb5b7f865d58 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -141,6 +141,7 @@  static const struct vfio_device_ops vfio_pci_ops = {
 	.bind_iommufd	= vfio_iommufd_physical_bind,
 	.unbind_iommufd	= vfio_iommufd_physical_unbind,
 	.attach_ioas	= vfio_iommufd_physical_attach_ioas,
+	.detach_ioas	= vfio_iommufd_physical_detach_ioas,
 };
 
 static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
diff --git a/drivers/vfio/platform/vfio_amba.c b/drivers/vfio/platform/vfio_amba.c
index 83fe54015595..6464b3939ebc 100644
--- a/drivers/vfio/platform/vfio_amba.c
+++ b/drivers/vfio/platform/vfio_amba.c
@@ -119,6 +119,7 @@  static const struct vfio_device_ops vfio_amba_ops = {
 	.bind_iommufd	= vfio_iommufd_physical_bind,
 	.unbind_iommufd	= vfio_iommufd_physical_unbind,
 	.attach_ioas	= vfio_iommufd_physical_attach_ioas,
+	.detach_ioas	= vfio_iommufd_physical_detach_ioas,
 };
 
 static const struct amba_id pl330_ids[] = {
diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c
index 22a1efca32a8..8cf22fa65baa 100644
--- a/drivers/vfio/platform/vfio_platform.c
+++ b/drivers/vfio/platform/vfio_platform.c
@@ -108,6 +108,7 @@  static const struct vfio_device_ops vfio_platform_ops = {
 	.bind_iommufd	= vfio_iommufd_physical_bind,
 	.unbind_iommufd	= vfio_iommufd_physical_unbind,
 	.attach_ioas	= vfio_iommufd_physical_attach_ioas,
+	.detach_ioas	= vfio_iommufd_physical_detach_ioas,
 };
 
 static struct platform_driver vfio_platform_driver = {
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index d54c03248794..eb53b1f8c828 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -258,7 +258,8 @@  static int __vfio_register_dev(struct vfio_device *device,
 	if (WARN_ON(IS_ENABLED(CONFIG_IOMMUFD) &&
 		    (!device->ops->bind_iommufd ||
 		     !device->ops->unbind_iommufd ||
-		     !device->ops->attach_ioas)))
+		     !device->ops->attach_ioas ||
+		     !device->ops->detach_ioas)))
 		return -EINVAL;
 
 	/*
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index a689c64432b7..4078133c0316 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -72,7 +72,9 @@  struct vfio_device {
  * @bind_iommufd: Called when binding the device to an iommufd
  * @unbind_iommufd: Opposite of bind_iommufd
  * @attach_ioas: Called when attaching device to an IOAS/HWPT managed by the
- *		 bound iommufd. Undo in unbind_iommufd.
+ *		 bound iommufd. Undo in unbind_iommufd if @detach_ioas is not
+ *		 called.
+ * @detach_ioas: Opposite of attach_ioas
  * @open_device: Called when the first file descriptor is opened for this device
  * @close_device: Opposite of open_device
  * @read: Perform read(2) on device file descriptor
@@ -96,6 +98,7 @@  struct vfio_device_ops {
 				struct iommufd_ctx *ictx, u32 *out_device_id);
 	void	(*unbind_iommufd)(struct vfio_device *vdev);
 	int	(*attach_ioas)(struct vfio_device *vdev, u32 *pt_id);
+	void	(*detach_ioas)(struct vfio_device *vdev);
 	int	(*open_device)(struct vfio_device *vdev);
 	void	(*close_device)(struct vfio_device *vdev);
 	ssize_t	(*read)(struct vfio_device *vdev, char __user *buf,
@@ -118,6 +121,7 @@  int vfio_iommufd_physical_bind(struct vfio_device *vdev,
 void vfio_iommufd_physical_unbind(struct vfio_device *vdev);
 struct iommufd_ctx *vfio_iommufd_physical_ictx(struct vfio_device *vdev);
 int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id);
+void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev);
 int vfio_iommufd_emulated_bind(struct vfio_device *vdev,
 			       struct iommufd_ctx *ictx, u32 *out_device_id);
 void vfio_iommufd_emulated_unbind(struct vfio_device *vdev);
@@ -132,6 +136,8 @@  int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id);
 	((struct iommufd_ctx * (*)(struct vfio_device *vdev)) NULL)
 #define vfio_iommufd_physical_attach_ioas \
 	((int (*)(struct vfio_device *vdev, u32 *pt_id)) NULL)
+#define vfio_iommufd_physical_detach_ioas \
+	((void (*)(struct vfio_device *vdev)) NULL)
 #define vfio_iommufd_emulated_bind                                      \
 	((int (*)(struct vfio_device *vdev, struct iommufd_ctx *ictx,   \
 		  u32 *out_device_id)) NULL)