[PATCH 05/13] vfio/fsl: Move to the device set infrastructure

Jason Gunthorpe jgg at nvidia.com
Thu Jul 15 00:20:34 UTC 2021


FSL uses the internal reflck to implement the open_device() functionality,
conversion to the core code is straightforward.

The decision on which set to be part of is trivially based on the
is_fsl_mc_bus_dprc() and we use a 'struct device *' pointer as the set_id.

It isn't entirely clear what the device set lock is actually protecting,
but I think it is related to the interrupt setup.

Signed-off-by: Yishai Hadas <yishaih at nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/vfio/fsl-mc/vfio_fsl_mc.c         | 152 ++++------------------
 drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c    |   6 +-
 drivers/vfio/fsl-mc/vfio_fsl_mc_private.h |   7 -
 3 files changed, 26 insertions(+), 139 deletions(-)

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 3d2be06e1bc146..49b93de05d5d62 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -19,81 +19,10 @@
 
 static struct fsl_mc_driver vfio_fsl_mc_driver;
 
-static DEFINE_MUTEX(reflck_lock);
-
-static void vfio_fsl_mc_reflck_get(struct vfio_fsl_mc_reflck *reflck)
-{
-	kref_get(&reflck->kref);
-}
-
-static void vfio_fsl_mc_reflck_release(struct kref *kref)
-{
-	struct vfio_fsl_mc_reflck *reflck = container_of(kref,
-						      struct vfio_fsl_mc_reflck,
-						      kref);
-
-	mutex_destroy(&reflck->lock);
-	kfree(reflck);
-	mutex_unlock(&reflck_lock);
-}
-
-static void vfio_fsl_mc_reflck_put(struct vfio_fsl_mc_reflck *reflck)
-{
-	kref_put_mutex(&reflck->kref, vfio_fsl_mc_reflck_release, &reflck_lock);
-}
-
-static struct vfio_fsl_mc_reflck *vfio_fsl_mc_reflck_alloc(void)
-{
-	struct vfio_fsl_mc_reflck *reflck;
-
-	reflck = kzalloc(sizeof(*reflck), GFP_KERNEL);
-	if (!reflck)
-		return ERR_PTR(-ENOMEM);
-
-	kref_init(&reflck->kref);
-	mutex_init(&reflck->lock);
-
-	return reflck;
-}
-
-static int vfio_fsl_mc_reflck_attach(struct vfio_fsl_mc_device *vdev)
-{
-	int ret = 0;
-
-	mutex_lock(&reflck_lock);
-	if (is_fsl_mc_bus_dprc(vdev->mc_dev)) {
-		vdev->reflck = vfio_fsl_mc_reflck_alloc();
-		ret = PTR_ERR_OR_ZERO(vdev->reflck);
-	} else {
-		struct device *mc_cont_dev = vdev->mc_dev->dev.parent;
-		struct vfio_device *device;
-		struct vfio_fsl_mc_device *cont_vdev;
-
-		device = vfio_device_get_from_dev(mc_cont_dev);
-		if (!device) {
-			ret = -ENODEV;
-			goto unlock;
-		}
-
-		cont_vdev =
-			container_of(device, struct vfio_fsl_mc_device, vdev);
-		if (!cont_vdev || !cont_vdev->reflck) {
-			vfio_device_put(device);
-			ret = -ENODEV;
-			goto unlock;
-		}
-		vfio_fsl_mc_reflck_get(cont_vdev->reflck);
-		vdev->reflck = cont_vdev->reflck;
-		vfio_device_put(device);
-	}
-
-unlock:
-	mutex_unlock(&reflck_lock);
-	return ret;
-}
-
-static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
+static int vfio_fsl_mc_open_device(struct vfio_device *core_vdev)
 {
+	struct vfio_fsl_mc_device *vdev =
+		container_of(core_vdev, struct vfio_fsl_mc_device, vdev);
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	int count = mc_dev->obj_desc.region_count;
 	int i;
@@ -136,58 +65,30 @@ static void vfio_fsl_mc_regions_cleanup(struct vfio_fsl_mc_device *vdev)
 	kfree(vdev->regions);
 }
 
-static int vfio_fsl_mc_open(struct vfio_device *core_vdev)
-{
-	struct vfio_fsl_mc_device *vdev =
-		container_of(core_vdev, struct vfio_fsl_mc_device, vdev);
-	int ret = 0;
-
-	mutex_lock(&vdev->reflck->lock);
-	if (!vdev->refcnt) {
-		ret = vfio_fsl_mc_regions_init(vdev);
-		if (ret)
-			goto out;
-	}
-	vdev->refcnt++;
-out:
-	mutex_unlock(&vdev->reflck->lock);
 
-	return ret;
-}
-
-static void vfio_fsl_mc_release(struct vfio_device *core_vdev)
+static void vfio_fsl_mc_close_device(struct vfio_device *core_vdev)
 {
 	struct vfio_fsl_mc_device *vdev =
 		container_of(core_vdev, struct vfio_fsl_mc_device, vdev);
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
+	struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
 	int ret;
 
-	mutex_lock(&vdev->reflck->lock);
+	vfio_fsl_mc_regions_cleanup(vdev);
 
-	if (!(--vdev->refcnt)) {
-		struct fsl_mc_device *mc_dev = vdev->mc_dev;
-		struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
-		struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
-
-		vfio_fsl_mc_regions_cleanup(vdev);
+	/* reset the device before cleaning up the interrupts */
+	ret = dprc_reset_container(mc_cont->mc_io, 0, mc_cont->mc_handle,
+				   mc_cont->obj_desc.id,
+				   DPRC_RESET_OPTION_NON_RECURSIVE);
 
-		/* reset the device before cleaning up the interrupts */
-		ret = dprc_reset_container(mc_cont->mc_io, 0,
-		      mc_cont->mc_handle,
-			  mc_cont->obj_desc.id,
-			  DPRC_RESET_OPTION_NON_RECURSIVE);
+	if (WARN_ON(ret))
+		dev_warn(&mc_cont->dev,
+			 "VFIO_FLS_MC: reset device has failed (%d)\n", ret);
 
-		if (ret) {
-			dev_warn(&mc_cont->dev, "VFIO_FLS_MC: reset device has failed (%d)\n",
-				 ret);
-			WARN_ON(1);
-		}
+	vfio_fsl_mc_irqs_cleanup(vdev);
 
-		vfio_fsl_mc_irqs_cleanup(vdev);
-
-		fsl_mc_cleanup_irq_pool(mc_cont);
-	}
-
-	mutex_unlock(&vdev->reflck->lock);
+	fsl_mc_cleanup_irq_pool(mc_cont);
 }
 
 static long vfio_fsl_mc_ioctl(struct vfio_device *core_vdev,
@@ -504,8 +405,8 @@ static int vfio_fsl_mc_mmap(struct vfio_device *core_vdev,
 
 static const struct vfio_device_ops vfio_fsl_mc_ops = {
 	.name		= "vfio-fsl-mc",
-	.open		= vfio_fsl_mc_open,
-	.release	= vfio_fsl_mc_release,
+	.open_device	= vfio_fsl_mc_open_device,
+	.close_device	= vfio_fsl_mc_close_device,
 	.ioctl		= vfio_fsl_mc_ioctl,
 	.read		= vfio_fsl_mc_read,
 	.write		= vfio_fsl_mc_write,
@@ -625,13 +526,15 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 	vdev->mc_dev = mc_dev;
 	mutex_init(&vdev->igate);
 
-	ret = vfio_fsl_mc_reflck_attach(vdev);
+	ret = vfio_assign_device_set(&vdev->vdev, is_fsl_mc_bus_dprc(mc_dev) ?
+							  &mc_dev->dev :
+							  mc_dev->dev.parent);
 	if (ret)
 		goto out_uninit;
 
 	ret = vfio_fsl_mc_init_device(vdev);
 	if (ret)
-		goto out_reflck;
+		goto out_uninit;
 
 	ret = vfio_register_group_dev(&vdev->vdev);
 	if (ret) {
@@ -639,12 +542,6 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 		goto out_device;
 	}
 
-	/*
-	 * This triggers recursion into vfio_fsl_mc_probe() on another device
-	 * and the vfio_fsl_mc_reflck_attach() must succeed, which relies on the
-	 * vfio_add_group_dev() above. It has no impact on this vdev, so it is
-	 * safe to be after the vfio device is made live.
-	 */
 	ret = vfio_fsl_mc_scan_container(mc_dev);
 	if (ret)
 		goto out_group_dev;
@@ -655,8 +552,6 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 	vfio_unregister_group_dev(&vdev->vdev);
 out_device:
 	vfio_fsl_uninit_device(vdev);
-out_reflck:
-	vfio_fsl_mc_reflck_put(vdev->reflck);
 out_uninit:
 	vfio_uninit_group_dev(&vdev->vdev);
 	kfree(vdev);
@@ -676,7 +571,6 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
 	dprc_remove_devices(mc_dev, NULL, 0);
 	vfio_fsl_uninit_device(vdev);
 	vfio_uninit_group_dev(&vdev->vdev);
-	vfio_fsl_mc_reflck_put(vdev->reflck);
 
 	kfree(vdev);
 	vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
index 0d9f3002df7f51..77e584093a233d 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
@@ -120,7 +120,7 @@ static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
 	if (start != 0 || count != 1)
 		return -EINVAL;
 
-	mutex_lock(&vdev->reflck->lock);
+	mutex_lock(&vdev->vdev.dev_set->lock);
 	ret = fsl_mc_populate_irq_pool(mc_cont,
 			FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
 	if (ret)
@@ -129,7 +129,7 @@ static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
 	ret = vfio_fsl_mc_irqs_allocate(vdev);
 	if (ret)
 		goto unlock;
-	mutex_unlock(&vdev->reflck->lock);
+	mutex_unlock(&vdev->vdev.dev_set->lock);
 
 	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
 		s32 fd = *(s32 *)data;
@@ -154,7 +154,7 @@ static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
 	return 0;
 
 unlock:
-	mutex_unlock(&vdev->reflck->lock);
+	mutex_unlock(&vdev->vdev.dev_set->lock);
 	return ret;
 
 }
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index 89700e00e77d10..4ad63ececb914b 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -22,11 +22,6 @@ struct vfio_fsl_mc_irq {
 	char            *name;
 };
 
-struct vfio_fsl_mc_reflck {
-	struct kref		kref;
-	struct mutex		lock;
-};
-
 struct vfio_fsl_mc_region {
 	u32			flags;
 	u32			type;
@@ -39,9 +34,7 @@ struct vfio_fsl_mc_device {
 	struct vfio_device		vdev;
 	struct fsl_mc_device		*mc_dev;
 	struct notifier_block        nb;
-	int				refcnt;
 	struct vfio_fsl_mc_region	*regions;
-	struct vfio_fsl_mc_reflck   *reflck;
 	struct mutex         igate;
 	struct vfio_fsl_mc_irq      *mc_irqs;
 };
-- 
2.32.0



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