Merge tag 'vfio-v5.15-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Fix dma-valid return WAITED implementation (Anthony Yznaga)

 - SPDX license cleanups (Cai Huoqing)

 - Split vfio-pci-core from vfio-pci and enhance PCI driver matching to
   support future vendor provided vfio-pci variants (Yishai Hadas, Max
   Gurtovoy, Jason Gunthorpe)

 - Replace duplicated reflck with core support for managing first open,
   last close, and device sets (Jason Gunthorpe, Max Gurtovoy, Yishai
   Hadas)

 - Fix non-modular mdev support and don't nag about request callback
   support (Christoph Hellwig)

 - Add semaphore to protect instruction intercept handler and replace
   open-coded locks in vfio-ap driver (Tony Krowiak)

 - Convert vfio-ap to vfio_register_group_dev() API (Jason Gunthorpe)

* tag 'vfio-v5.15-rc1' of git://github.com/awilliam/linux-vfio: (37 commits)
  vfio/pci: Introduce vfio_pci_core.ko
  vfio: Use kconfig if XX/endif blocks instead of repeating 'depends on'
  vfio: Use select for eventfd
  PCI / VFIO: Add 'override_only' support for VFIO PCI sub system
  PCI: Add 'override_only' field to struct pci_device_id
  vfio/pci: Move module parameters to vfio_pci.c
  vfio/pci: Move igd initialization to vfio_pci.c
  vfio/pci: Split the pci_driver code out of vfio_pci_core.c
  vfio/pci: Include vfio header in vfio_pci_core.h
  vfio/pci: Rename ops functions to fit core namings
  vfio/pci: Rename vfio_pci_device to vfio_pci_core_device
  vfio/pci: Rename vfio_pci_private.h to vfio_pci_core.h
  vfio/pci: Rename vfio_pci.c to vfio_pci_core.c
  vfio/ap_ops: Convert to use vfio_register_group_dev()
  s390/vfio-ap: replace open coded locks for VFIO_GROUP_NOTIFY_SET_KVM notification
  s390/vfio-ap: r/w lock for PQAP interception handler function pointer
  vfio/type1: Fix vfio_find_dma_valid return
  vfio-pci/zdev: Remove repeated verbose license text
  vfio: platform: reset: Convert to SPDX identifier
  vfio: Remove struct vfio_device_ops open/release
  ...

1 files changed, 19 insertions, 21 deletions

diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 6c0f229db36a..c313ab4d1f4e 100644
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -129,7 +129,7 @@ static dev_t		mbochs_devt;
 static struct class	*mbochs_class;
 static struct cdev	mbochs_cdev;
 static struct device	mbochs_dev;
-static int		mbochs_used_mbytes;
+static atomic_t mbochs_avail_mbytes;
 static const struct vfio_device_ops mbochs_dev_ops;
 
 struct vfio_region_info_ext {
@@ -507,18 +507,22 @@ static int mbochs_reset(struct mdev_state *mdev_state)
 
 static int mbochs_probe(struct mdev_device *mdev)
 {
+	int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
 	const struct mbochs_type *type =
 		&mbochs_types[mdev_get_type_group_id(mdev)];
 	struct device *dev = mdev_dev(mdev);
 	struct mdev_state *mdev_state;
 	int ret = -ENOMEM;
 
-	if (type->mbytes + mbochs_used_mbytes > max_mbytes)
-		return -ENOMEM;
+	do {
+		if (avail_mbytes < type->mbytes)
+			return -ENOSPC;
+	} while (!atomic_try_cmpxchg(&mbochs_avail_mbytes, &avail_mbytes,
+				     avail_mbytes - type->mbytes));
 
 	mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
 	if (mdev_state == NULL)
-		return -ENOMEM;
+		goto err_avail;
 	vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mbochs_dev_ops);
 
 	mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL);
@@ -549,17 +553,18 @@ static int mbochs_probe(struct mdev_device *mdev)
 	mbochs_create_config_space(mdev_state);
 	mbochs_reset(mdev_state);
 
-	mbochs_used_mbytes += type->mbytes;
-
 	ret = vfio_register_group_dev(&mdev_state->vdev);
 	if (ret)
 		goto err_mem;
 	dev_set_drvdata(&mdev->dev, mdev_state);
 	return 0;
-
 err_mem:
+	vfio_uninit_group_dev(&mdev_state->vdev);
+	kfree(mdev_state->pages);
 	kfree(mdev_state->vconfig);
 	kfree(mdev_state);
+err_avail:
+	atomic_add(type->mbytes, &mbochs_avail_mbytes);
 	return ret;
 }
 
@@ -567,8 +572,9 @@ static void mbochs_remove(struct mdev_device *mdev)
 {
 	struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
 
-	mbochs_used_mbytes -= mdev_state->type->mbytes;
 	vfio_unregister_group_dev(&mdev_state->vdev);
+	vfio_uninit_group_dev(&mdev_state->vdev);
+	atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes);
 	kfree(mdev_state->pages);
 	kfree(mdev_state->vconfig);
 	kfree(mdev_state);
@@ -1272,15 +1278,7 @@ static long mbochs_ioctl(struct vfio_device *vdev, unsigned int cmd,
 	return -ENOTTY;
 }
 
-static int mbochs_open(struct vfio_device *vdev)
-{
-	if (!try_module_get(THIS_MODULE))
-		return -ENODEV;
-
-	return 0;
-}
-
-static void mbochs_close(struct vfio_device *vdev)
+static void mbochs_close_device(struct vfio_device *vdev)
 {
 	struct mdev_state *mdev_state =
 		container_of(vdev, struct mdev_state, vdev);
@@ -1300,7 +1298,6 @@ static void mbochs_close(struct vfio_device *vdev)
 	mbochs_put_pages(mdev_state);
 
 	mutex_unlock(&mdev_state->ops_lock);
-	module_put(THIS_MODULE);
 }
 
 static ssize_t
@@ -1355,7 +1352,7 @@ static ssize_t available_instances_show(struct mdev_type *mtype,
 {
 	const struct mbochs_type *type =
 		&mbochs_types[mtype_get_type_group_id(mtype)];
-	int count = (max_mbytes - mbochs_used_mbytes) / type->mbytes;
+	int count = atomic_read(&mbochs_avail_mbytes) / type->mbytes;
 
 	return sprintf(buf, "%d\n", count);
 }
@@ -1399,8 +1396,7 @@ static struct attribute_group *mdev_type_groups[] = {
 };
 
 static const struct vfio_device_ops mbochs_dev_ops = {
-	.open = mbochs_open,
-	.release = mbochs_close,
+	.close_device = mbochs_close_device,
 	.read = mbochs_read,
 	.write = mbochs_write,
 	.ioctl = mbochs_ioctl,
@@ -1437,6 +1433,8 @@ static int __init mbochs_dev_init(void)
 {
 	int ret = 0;
 
+	atomic_set(&mbochs_avail_mbytes, max_mbytes);
+
 	ret = alloc_chrdev_region(&mbochs_devt, 0, MINORMASK + 1, MBOCHS_NAME);
 	if (ret < 0) {
 		pr_err("Error: failed to register mbochs_dev, err: %d\n", ret);