[PATCH 13/13] vfio: powerpc/spapr: Enable Dynamic DMA windows

@@ -190,18 +190,25 @@ static void tce_iommu_disable(struct tce_container *container)
 
 	container->enabled = false;
 
-	if (!container->grp || !current->mm)
+	if (!container->grp)
 		return;
 
 	data = iommu_group_get_iommudata(container->grp);
 	if (!data || !data->iommu_owner || !data->ops->get_table)
 		return;
 
-	tbl = data->ops->get_table(data, 0);
-	if (!tbl)
-		return;
+	if (current->mm) {
+		tbl = data->ops->get_table(data, 0);
+		if (tbl)
+			decrement_locked_vm(tbl);
 
-	decrement_locked_vm(tbl);
+		tbl = data->ops->get_table(data, 1);
+		if (tbl)
+			decrement_locked_vm(tbl);
+	}
+
+	if (data->ops->reset)
+		data->ops->reset(data);
 }
 
 static void *tce_iommu_open(unsigned long arg)

@@ -243,7 +250,7 @@ static long tce_iommu_ioctl(void *iommu_data,
 				 unsigned int cmd, unsigned long arg)
 {
 	struct tce_container *container = iommu_data;
-	unsigned long minsz;
+	unsigned long minsz, ddwsz;
 	long ret;
 
 	switch (cmd) {

@@ -288,6 +295,28 @@ static long tce_iommu_ioctl(void *iommu_data,
 		info.dma32_window_size = tbl->it_size << tbl->it_page_shift;
 		info.flags = 0;
 
+		ddwsz = offsetofend(struct vfio_iommu_spapr_tce_info,
+				page_size_mask);
+
+		if (info.argsz == ddwsz) {
+			if (data->ops->query && data->ops->create &&
+					data->ops->remove) {
+				info.flags |= VFIO_IOMMU_SPAPR_TCE_FLAG_DDW;
+
+				ret = data->ops->query(data,
+						&info.current_windows,
+						&info.windows_available,
+						&info.page_size_mask);
+				if (ret)
+					return ret;
+			} else {
+				info.current_windows = 0;
+				info.windows_available = 0;
+				info.page_size_mask = 0;
+			}
+			minsz = ddwsz;
+		}
+
 		if (copy_to_user((void __user *)arg, &info, minsz))
 			return -EFAULT;
 

@@ -412,12 +441,106 @@ static long tce_iommu_ioctl(void *iommu_data,
 		tce_iommu_disable(container);
 		mutex_unlock(&container->lock);
 		return 0;
+
 	case VFIO_EEH_PE_OP:
 		if (!container->grp)
 			return -ENODEV;
 
 		return vfio_spapr_iommu_eeh_ioctl(container->grp,
 						  cmd, arg);
+
+	case VFIO_IOMMU_SPAPR_TCE_CREATE: {
+		struct vfio_iommu_spapr_tce_create create;
+		struct spapr_tce_iommu_group *data;
+		struct iommu_table *tbl;
+
+		if (WARN_ON(!container->grp))
+			return -ENXIO;
+
+		data = iommu_group_get_iommudata(container->grp);
+
+		minsz = offsetofend(struct vfio_iommu_spapr_tce_create,
+				start_addr);
+
+		if (copy_from_user(&create, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (create.argsz < minsz)
+			return -EINVAL;
+
+		if (create.flags)
+			return -EINVAL;
+
+		if (!data->ops->create || !data->iommu_owner)
+			return -ENOSYS;
+
+		BUG_ON(!data || !data->ops || !data->ops->remove);
+
+		ret = data->ops->create(data, create.page_shift,
+				create.window_shift, &tbl);
+		if (ret)
+			return ret;
+
+		ret = try_increment_locked_vm(tbl);
+		if (ret) {
+			data->ops->remove(data, tbl);
+			return ret;
+		}
+
+		create.start_addr = tbl->it_offset << tbl->it_page_shift;
+
+		if (copy_to_user((void __user *)arg, &create, minsz)) {
+			data->ops->remove(data, tbl);
+			decrement_locked_vm(tbl);
+			return -EFAULT;
+		}
+		mutex_lock(&container->lock);
+		++container->windows_num;
+		mutex_unlock(&container->lock);
+
+		return ret;
+	}
+	case VFIO_IOMMU_SPAPR_TCE_REMOVE: {
+		struct vfio_iommu_spapr_tce_remove remove;
+		struct spapr_tce_iommu_group *data;
+		struct iommu_table *tbl;
+
+		if (WARN_ON(!container->grp))
+			return -ENXIO;
+
+		data = iommu_group_get_iommudata(container->grp);
+
+		minsz = offsetofend(struct vfio_iommu_spapr_tce_remove,
+				start_addr);
+
+		if (copy_from_user(&remove, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (remove.argsz < minsz)
+			return -EINVAL;
+
+		if (remove.flags)
+			return -EINVAL;
+
+		if (!data->ops->remove || !data->iommu_owner)
+			return -ENOSYS;
+
+		tbl = spapr_tce_find_table(container, data, remove.start_addr);
+		if (!tbl)
+			return -EINVAL;
+
+		ret = data->ops->remove(data, tbl);
+		if (ret)
+			return ret;
+
+		decrement_locked_vm(tbl);
+
+		mutex_lock(&container->lock);
+		--container->windows_num;
+		mutex_unlock(&container->lock);
+
+		return 0;
+	}
 	}
 
 	return -ENOTTY;

@@ -451,9 +451,13 @@ struct vfio_iommu_type1_dma_unmap {
  */
 struct vfio_iommu_spapr_tce_info {
 	__u32 argsz;
-	__u32 flags;			/* reserved for future use */
+	__u32 flags;
+#define VFIO_IOMMU_SPAPR_TCE_FLAG_DDW	1 /* Support dynamic windows */
 	__u32 dma32_window_start;	/* 32 bit window start (bytes) */
 	__u32 dma32_window_size;	/* 32 bit window size (bytes) */
+	__u32 current_windows;
+	__u32 windows_available;
+	__u32 page_size_mask;
 };
 
 #define VFIO_IOMMU_SPAPR_TCE_GET_INFO	_IO(VFIO_TYPE, VFIO_BASE + 12)

@@ -489,6 +493,25 @@ struct vfio_eeh_pe_op {
 
 #define VFIO_EEH_PE_OP			_IO(VFIO_TYPE, VFIO_BASE + 21)
 
+struct vfio_iommu_spapr_tce_create {
+	__u32 argsz;
+	__u32 flags;
+	/* in */
+	__u32 page_shift;
+	__u32 window_shift;
+	/* out */
+	__u64 start_addr;
+};
+#define VFIO_IOMMU_SPAPR_TCE_CREATE	_IO(VFIO_TYPE, VFIO_BASE + 18)
+
+struct vfio_iommu_spapr_tce_remove {
+	__u32 argsz;
+	__u32 flags;
+	/* in */
+	__u64 start_addr;
+};
+#define VFIO_IOMMU_SPAPR_TCE_REMOVE	_IO(VFIO_TYPE, VFIO_BASE + 19)
+
 /* ***************************************************************** */
 
 #endif /* _UAPIVFIO_H */