Merge tag 'vfio-v4.10-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - VFIO updates for v4.10 primarily include a new Mediated Device
   interface, which essentially allows software defined devices to be
   exposed to users through VFIO. The host vendor driver providing this
   virtual device polices, or mediates user access to the device.

   These devices often incorporate portions of real devices, for
   instance the primary initial users of this interface expose vGPUs
   which allow the user to map mediated devices, or mdevs, to a portion
   of a physical GPU. QEMU composes these mdevs into PCI representations
   using the existing VFIO user API. This enables both Intel KVM-GT
   support, which is also expected to arrive into Linux mainline during
   the v4.10 merge window, as well as NVIDIA vGPU, and also Channel I/O
   devices (aka CCW devices) for s390 virtualization support. (Kirti
   Wankhede, Neo Jia)

 - Drop unnecessary uses of pcibios_err_to_errno() (Cao Jin)

 - Fixes to VFIO capability chain handling (Eric Auger)

 - Error handling fixes for fallout from mdev (Christophe JAILLET)

 - Notifiers to expose struct kvm to mdev vendor drivers (Jike Song)

 - type1 IOMMU model search fixes (Kirti Wankhede, Neo Jia)

* tag 'vfio-v4.10-rc1' of git://github.com/awilliam/linux-vfio: (30 commits)
  vfio iommu type1: Fix size argument to vfio_find_dma() in pin_pages/unpin_pages
  vfio iommu type1: Fix size argument to vfio_find_dma() during DMA UNMAP.
  vfio iommu type1: WARN_ON if notifier block is not unregistered
  kvm: set/clear kvm to/from vfio_group when group add/delete
  vfio: support notifier chain in vfio_group
  vfio: vfio_register_notifier: classify iommu notifier
  vfio: Fix handling of error returned by 'vfio_group_get_from_dev()'
  vfio: fix vfio_info_cap_add/shift
  vfio/pci: Drop unnecessary pcibios_err_to_errno()
  MAINTAINERS: Add entry VFIO based Mediated device drivers
  docs: Sample driver to demonstrate how to use Mediated device framework.
  docs: Sysfs ABI for mediated device framework
  docs: Add Documentation for Mediated devices
  vfio: Define device_api strings
  vfio_platform: Updated to use vfio_set_irqs_validate_and_prepare()
  vfio_pci: Updated to use vfio_set_irqs_validate_and_prepare()
  vfio: Introduce vfio_set_irqs_validate_and_prepare()
  vfio_pci: Update vfio_pci to use vfio_info_add_capability()
  vfio: Introduce common function to add capabilities
  vfio iommu: Add blocking notifier to notify DMA_UNMAP
  ...

1 files changed, 438 insertions, 23 deletions

diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index d1d70e0b011b..9901c4671e2f 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -86,6 +86,8 @@ struct vfio_group {
 	struct mutex			unbound_lock;
 	atomic_t			opened;
 	bool				noiommu;
+	struct kvm			*kvm;
+	struct blocking_notifier_head	notifier;
 };
 
 struct vfio_device {
@@ -339,6 +341,7 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group)
 #ifdef CONFIG_VFIO_NOIOMMU
 	group->noiommu = (iommu_group_get_iommudata(iommu_group) == &noiommu);
 #endif
+	BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);
 
 	group->nb.notifier_call = vfio_iommu_group_notifier;
 
@@ -480,6 +483,21 @@ static struct vfio_group *vfio_group_get_from_minor(int minor)
 	return group;
 }
 
+static struct vfio_group *vfio_group_get_from_dev(struct device *dev)
+{
+	struct iommu_group *iommu_group;
+	struct vfio_group *group;
+
+	iommu_group = iommu_group_get(dev);
+	if (!iommu_group)
+		return NULL;
+
+	group = vfio_group_get_from_iommu(iommu_group);
+	iommu_group_put(iommu_group);
+
+	return group;
+}
+
 /**
  * Device objects - create, release, get, put, search
  */
@@ -811,16 +829,10 @@ EXPORT_SYMBOL_GPL(vfio_add_group_dev);
  */
 struct vfio_device *vfio_device_get_from_dev(struct device *dev)
 {
-	struct iommu_group *iommu_group;
 	struct vfio_group *group;
 	struct vfio_device *device;
 
-	iommu_group = iommu_group_get(dev);
-	if (!iommu_group)
-		return NULL;
-
-	group = vfio_group_get_from_iommu(iommu_group);
-	iommu_group_put(iommu_group);
+	group = vfio_group_get_from_dev(dev);
 	if (!group)
 		return NULL;
 
@@ -1376,6 +1388,23 @@ static bool vfio_group_viable(struct vfio_group *group)
 					 group, vfio_dev_viable) == 0);
 }
 
+static int vfio_group_add_container_user(struct vfio_group *group)
+{
+	if (!atomic_inc_not_zero(&group->container_users))
+		return -EINVAL;
+
+	if (group->noiommu) {
+		atomic_dec(&group->container_users);
+		return -EPERM;
+	}
+	if (!group->container->iommu_driver || !vfio_group_viable(group)) {
+		atomic_dec(&group->container_users);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static const struct file_operations vfio_device_fops;
 
 static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
@@ -1555,6 +1584,9 @@ static int vfio_group_fops_release(struct inode *inode, struct file *filep)
 
 	filep->private_data = NULL;
 
+	/* Any user didn't unregister? */
+	WARN_ON(group->notifier.head);
+
 	vfio_group_try_dissolve_container(group);
 
 	atomic_dec(&group->opened);
@@ -1685,23 +1717,14 @@ static const struct file_operations vfio_device_fops = {
 struct vfio_group *vfio_group_get_external_user(struct file *filep)
 {
 	struct vfio_group *group = filep->private_data;
+	int ret;
 
 	if (filep->f_op != &vfio_group_fops)
 		return ERR_PTR(-EINVAL);
 
-	if (!atomic_inc_not_zero(&group->container_users))
-		return ERR_PTR(-EINVAL);
-
-	if (group->noiommu) {
-		atomic_dec(&group->container_users);
-		return ERR_PTR(-EPERM);
-	}
-
-	if (!group->container->iommu_driver ||
-			!vfio_group_viable(group)) {
-		atomic_dec(&group->container_users);
-		return ERR_PTR(-EINVAL);
-	}
+	ret = vfio_group_add_container_user(group);
+	if (ret)
+		return ERR_PTR(ret);
 
 	vfio_group_get(group);
 
@@ -1763,7 +1786,7 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps,
 	header->version = version;
 
 	/* Add to the end of the capability chain */
-	for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next)
+	for (tmp = buf; tmp->next; tmp = buf + tmp->next)
 		; /* nothing */
 
 	tmp->next = caps->size;
@@ -1776,11 +1799,403 @@ EXPORT_SYMBOL_GPL(vfio_info_cap_add);
 void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
 {
 	struct vfio_info_cap_header *tmp;
+	void *buf = (void *)caps->buf;
 
-	for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next - offset)
+	for (tmp = buf; tmp->next; tmp = buf + tmp->next - offset)
 		tmp->next += offset;
 }
-EXPORT_SYMBOL_GPL(vfio_info_cap_shift);
+EXPORT_SYMBOL(vfio_info_cap_shift);
+
+static int sparse_mmap_cap(struct vfio_info_cap *caps, void *cap_type)
+{
+	struct vfio_info_cap_header *header;
+	struct vfio_region_info_cap_sparse_mmap *sparse_cap, *sparse = cap_type;
+	size_t size;
+
+	size = sizeof(*sparse) + sparse->nr_areas *  sizeof(*sparse->areas);
+	header = vfio_info_cap_add(caps, size,
+				   VFIO_REGION_INFO_CAP_SPARSE_MMAP, 1);
+	if (IS_ERR(header))
+		return PTR_ERR(header);
+
+	sparse_cap = container_of(header,
+			struct vfio_region_info_cap_sparse_mmap, header);
+	sparse_cap->nr_areas = sparse->nr_areas;
+	memcpy(sparse_cap->areas, sparse->areas,
+	       sparse->nr_areas * sizeof(*sparse->areas));
+	return 0;
+}
+
+static int region_type_cap(struct vfio_info_cap *caps, void *cap_type)
+{
+	struct vfio_info_cap_header *header;
+	struct vfio_region_info_cap_type *type_cap, *cap = cap_type;
+
+	header = vfio_info_cap_add(caps, sizeof(*cap),
+				   VFIO_REGION_INFO_CAP_TYPE, 1);
+	if (IS_ERR(header))
+		return PTR_ERR(header);
+
+	type_cap = container_of(header, struct vfio_region_info_cap_type,
+				header);
+	type_cap->type = cap->type;
+	type_cap->subtype = cap->subtype;
+	return 0;
+}
+
+int vfio_info_add_capability(struct vfio_info_cap *caps, int cap_type_id,
+			     void *cap_type)
+{
+	int ret = -EINVAL;
+
+	if (!cap_type)
+		return 0;
+
+	switch (cap_type_id) {
+	case VFIO_REGION_INFO_CAP_SPARSE_MMAP:
+		ret = sparse_mmap_cap(caps, cap_type);
+		break;
+
+	case VFIO_REGION_INFO_CAP_TYPE:
+		ret = region_type_cap(caps, cap_type);
+		break;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(vfio_info_add_capability);
+
+int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr, int num_irqs,
+				       int max_irq_type, size_t *data_size)
+{
+	unsigned long minsz;
+	size_t size;
+
+	minsz = offsetofend(struct vfio_irq_set, count);
+
+	if ((hdr->argsz < minsz) || (hdr->index >= max_irq_type) ||
+	    (hdr->count >= (U32_MAX - hdr->start)) ||
+	    (hdr->flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
+				VFIO_IRQ_SET_ACTION_TYPE_MASK)))
+		return -EINVAL;
+
+	if (data_size)
+		*data_size = 0;
+
+	if (hdr->start >= num_irqs || hdr->start + hdr->count > num_irqs)
+		return -EINVAL;
+
+	switch (hdr->flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
+	case VFIO_IRQ_SET_DATA_NONE:
+		size = 0;
+		break;
+	case VFIO_IRQ_SET_DATA_BOOL:
+		size = sizeof(uint8_t);
+		break;
+	case VFIO_IRQ_SET_DATA_EVENTFD:
+		size = sizeof(int32_t);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (size) {
+		if (hdr->argsz - minsz < hdr->count * size)
+			return -EINVAL;
+
+		if (!data_size)
+			return -EINVAL;
+
+		*data_size = hdr->count * size;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare);
+
+/*
+ * Pin a set of guest PFNs and return their associated host PFNs for local
+ * domain only.
+ * @dev [in]     : device
+ * @user_pfn [in]: array of user/guest PFNs to be unpinned.
+ * @npage [in]   : count of elements in user_pfn array.  This count should not
+ *		   be greater VFIO_PIN_PAGES_MAX_ENTRIES.
+ * @prot [in]    : protection flags
+ * @phys_pfn[out]: array of host PFNs
+ * Return error or number of pages pinned.
+ */
+int vfio_pin_pages(struct device *dev, unsigned long *user_pfn, int npage,
+		   int prot, unsigned long *phys_pfn)
+{
+	struct vfio_container *container;
+	struct vfio_group *group;
+	struct vfio_iommu_driver *driver;
+	int ret;
+
+	if (!dev || !user_pfn || !phys_pfn || !npage)
+		return -EINVAL;
+
+	if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
+		return -E2BIG;
+
+	group = vfio_group_get_from_dev(dev);
+	if (!group)
+		return -ENODEV;
+
+	ret = vfio_group_add_container_user(group);
+	if (ret)
+		goto err_pin_pages;
+
+	container = group->container;
+	down_read(&container->group_lock);
+
+	driver = container->iommu_driver;
+	if (likely(driver && driver->ops->pin_pages))
+		ret = driver->ops->pin_pages(container->iommu_data, user_pfn,
+					     npage, prot, phys_pfn);
+	else
+		ret = -ENOTTY;
+
+	up_read(&container->group_lock);
+	vfio_group_try_dissolve_container(group);
+
+err_pin_pages:
+	vfio_group_put(group);
+	return ret;
+}
+EXPORT_SYMBOL(vfio_pin_pages);
+
+/*
+ * Unpin set of host PFNs for local domain only.
+ * @dev [in]     : device
+ * @user_pfn [in]: array of user/guest PFNs to be unpinned. Number of user/guest
+ *		   PFNs should not be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
+ * @npage [in]   : count of elements in user_pfn array.  This count should not
+ *                 be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
+ * Return error or number of pages unpinned.
+ */
+int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
+{
+	struct vfio_container *container;
+	struct vfio_group *group;
+	struct vfio_iommu_driver *driver;
+	int ret;
+
+	if (!dev || !user_pfn || !npage)
+		return -EINVAL;
+
+	if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
+		return -E2BIG;
+
+	group = vfio_group_get_from_dev(dev);
+	if (!group)
+		return -ENODEV;
+
+	ret = vfio_group_add_container_user(group);
+	if (ret)
+		goto err_unpin_pages;
+
+	container = group->container;
+	down_read(&container->group_lock);
+
+	driver = container->iommu_driver;
+	if (likely(driver && driver->ops->unpin_pages))
+		ret = driver->ops->unpin_pages(container->iommu_data, user_pfn,
+					       npage);
+	else
+		ret = -ENOTTY;
+
+	up_read(&container->group_lock);
+	vfio_group_try_dissolve_container(group);
+
+err_unpin_pages:
+	vfio_group_put(group);
+	return ret;
+}
+EXPORT_SYMBOL(vfio_unpin_pages);
+
+static int vfio_register_iommu_notifier(struct vfio_group *group,
+					unsigned long *events,
+					struct notifier_block *nb)
+{
+	struct vfio_container *container;
+	struct vfio_iommu_driver *driver;
+	int ret;
+
+	ret = vfio_group_add_container_user(group);
+	if (ret)
+		return -EINVAL;
+
+	container = group->container;
+	down_read(&container->group_lock);
+
+	driver = container->iommu_driver;
+	if (likely(driver && driver->ops->register_notifier))
+		ret = driver->ops->register_notifier(container->iommu_data,
+						     events, nb);
+	else
+		ret = -ENOTTY;
+
+	up_read(&container->group_lock);
+	vfio_group_try_dissolve_container(group);
+
+	return ret;
+}
+
+static int vfio_unregister_iommu_notifier(struct vfio_group *group,
+					  struct notifier_block *nb)
+{
+	struct vfio_container *container;
+	struct vfio_iommu_driver *driver;
+	int ret;
+
+	ret = vfio_group_add_container_user(group);
+	if (ret)
+		return -EINVAL;
+
+	container = group->container;
+	down_read(&container->group_lock);
+
+	driver = container->iommu_driver;
+	if (likely(driver && driver->ops->unregister_notifier))
+		ret = driver->ops->unregister_notifier(container->iommu_data,
+						       nb);
+	else
+		ret = -ENOTTY;
+
+	up_read(&container->group_lock);
+	vfio_group_try_dissolve_container(group);
+
+	return ret;
+}
+
+void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm)
+{
+	group->kvm = kvm;
+	blocking_notifier_call_chain(&group->notifier,
+				VFIO_GROUP_NOTIFY_SET_KVM, kvm);
+}
+EXPORT_SYMBOL_GPL(vfio_group_set_kvm);
+
+static int vfio_register_group_notifier(struct vfio_group *group,
+					unsigned long *events,
+					struct notifier_block *nb)
+{
+	struct vfio_container *container;
+	int ret;
+	bool set_kvm = false;
+
+	if (*events & VFIO_GROUP_NOTIFY_SET_KVM)
+		set_kvm = true;
+
+	/* clear known events */
+	*events &= ~VFIO_GROUP_NOTIFY_SET_KVM;
+
+	/* refuse to continue if still events remaining */
+	if (*events)
+		return -EINVAL;
+
+	ret = vfio_group_add_container_user(group);
+	if (ret)
+		return -EINVAL;
+
+	container = group->container;
+	down_read(&container->group_lock);
+
+	ret = blocking_notifier_chain_register(&group->notifier, nb);
+
+	/*
+	 * The attaching of kvm and vfio_group might already happen, so
+	 * here we replay once upon registration.
+	 */
+	if (!ret && set_kvm && group->kvm)
+		blocking_notifier_call_chain(&group->notifier,
+					VFIO_GROUP_NOTIFY_SET_KVM, group->kvm);
+
+	up_read(&container->group_lock);
+	vfio_group_try_dissolve_container(group);
+
+	return ret;
+}
+
+static int vfio_unregister_group_notifier(struct vfio_group *group,
+					 struct notifier_block *nb)
+{
+	struct vfio_container *container;
+	int ret;
+
+	ret = vfio_group_add_container_user(group);
+	if (ret)
+		return -EINVAL;
+
+	container = group->container;
+	down_read(&container->group_lock);
+
+	ret = blocking_notifier_chain_unregister(&group->notifier, nb);
+
+	up_read(&container->group_lock);
+	vfio_group_try_dissolve_container(group);
+
+	return ret;
+}
+
+int vfio_register_notifier(struct device *dev, enum vfio_notify_type type,
+			   unsigned long *events, struct notifier_block *nb)
+{
+	struct vfio_group *group;
+	int ret;
+
+	if (!dev || !nb || !events || (*events == 0))
+		return -EINVAL;
+
+	group = vfio_group_get_from_dev(dev);
+	if (!group)
+		return -ENODEV;
+
+	switch (type) {
+	case VFIO_IOMMU_NOTIFY:
+		ret = vfio_register_iommu_notifier(group, events, nb);
+		break;
+	case VFIO_GROUP_NOTIFY:
+		ret = vfio_register_group_notifier(group, events, nb);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	vfio_group_put(group);
+	return ret;
+}
+EXPORT_SYMBOL(vfio_register_notifier);
+
+int vfio_unregister_notifier(struct device *dev, enum vfio_notify_type type,
+			     struct notifier_block *nb)
+{
+	struct vfio_group *group;
+	int ret;
+
+	if (!dev || !nb)
+		return -EINVAL;
+
+	group = vfio_group_get_from_dev(dev);
+	if (!group)
+		return -ENODEV;
+
+	switch (type) {
+	case VFIO_IOMMU_NOTIFY:
+		ret = vfio_unregister_iommu_notifier(group, nb);
+		break;
+	case VFIO_GROUP_NOTIFY:
+		ret = vfio_unregister_group_notifier(group, nb);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	vfio_group_put(group);
+	return ret;
+}
+EXPORT_SYMBOL(vfio_unregister_notifier);
 
 /**
  * Module/class support