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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _NE_MISC_DEV_H_
+#define _NE_MISC_DEV_H_
+
+#include <linux/cpumask.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/pci.h>
+#include <linux/wait.h>
+
+/* Entry in vCPU IDs list. */
+struct ne_vcpu_id {
+ /* CPU id associated with a given slot, apic id on x86. */
+ u32 vcpu_id;
+
+ struct list_head vcpu_id_list_entry;
+};
+
+/* Entry in memory regions list. */
+struct ne_mem_region {
+ struct list_head mem_region_list_entry;
+
+ /* Number of pages that make up the memory region. */
+ unsigned long nr_pages;
+
+ /* Pages that make up the user space memory region. */
+ struct page **pages;
+};
+
+/* Per-enclave data used for enclave lifetime management. */
+struct ne_enclave {
+ /**
+ * CPU pool with siblings of already allocated CPUs to an enclave.
+ * This is used when a CPU pool is set, to be able to know the CPU
+ * siblings for the hyperthreading (HT) setup.
+ */
+ cpumask_var_t cpu_siblings;
+
+ struct list_head enclave_list_entry;
+
+ /* Mutex for accessing this internal state. */
+ struct mutex enclave_info_mutex;
+
+ /**
+ * Wait queue used for out-of-band event notifications
+ * triggered from the PCI device event handler to the enclave
+ * process via the poll function.
+ */
+ wait_queue_head_t eventq;
+
+ /* Variable used to determine if the out-of-band event was triggered. */
+ bool has_event;
+
+ /**
+ * The maximum number of memory regions that can be handled by the
+ * lower levels.
+ */
+ u64 max_mem_regions;
+
+ /* Enclave memory regions list. */
+ struct list_head mem_regions_list;
+
+ /* Enclave process abstraction mm data struct. */
+ struct mm_struct *mm;
+
+ /* PCI device used for enclave lifetime management. */
+ struct pci_dev *pdev;
+
+ /* Slot unique id mapped to the enclave. */
+ u64 slot_uid;
+
+ /* Enclave state, updated during enclave lifetime. */
+ u16 state;
+
+ /* Enclave vCPUs list. */
+ struct list_head vcpu_ids_list;
+};
+
+/**
+ * States available for an enclave.
+ *
+ * TODO: Determine if the following states are exposing enough information
+ * to the kernel driver.
+ */
+enum ne_state {
+ /* NE_ENCLAVE_START ioctl was never issued for the enclave. */
+ NE_STATE_INIT = 0,
+
+ /**
+ * NE_ENCLAVE_START ioctl was issued and the enclave is running
+ * as expected.
+ */
+ NE_STATE_RUNNING = 2,
+
+ /* Enclave exited without userspace interaction. */
+ NE_STATE_STOPPED = U16_MAX,
+};
+
+/* Nitro Enclaves (NE) misc device */
+extern struct miscdevice ne_miscdevice;
+
+#endif /* _NE_MISC_DEV_H_ */