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Change-Id: I14b6becc908a0ac215769c32ee9c43db192ae6c8
diff --git a/kernel/ethosu_buffer.h b/kernel/ethosu_buffer.h
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+/*
+ * (C) COPYRIGHT 2020 ARM Limited. All rights reserved.
+ *
+ * This program is free software and is provided to you under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation, and any use by you of this program is subject to the terms
+ * of such GNU licence.
+ *
+ * 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, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#ifndef ETHOSU_BUFFER_H
+#define ETHOSU_BUFFER_H
+
+/****************************************************************************
+ * Includes
+ ****************************************************************************/
+
+#include <linux/kref.h>
+#include <linux/types.h>
+
+/****************************************************************************
+ * Types
+ ****************************************************************************/
+
+struct ethosu_device;
+struct device;
+
+/**
+ * struct ethosu_buffer - Buffer
+ * @dev: Device
+ * @file: File
+ * @kref: Reference counting
+ * @capacity: Maximum capacity of the buffer
+ * @offset: Offset to first byte of buffer
+ * @size: Size of the data in the buffer
+ * @cpu_addr: Kernel mapped address
+ * @dma_addr: DMA address
+ * @dma_addr_orig: Original DMA address before range mapping
+ *
+ * 'offset + size' must not be larger than 'capacity'.
+ */
+struct ethosu_buffer {
+ struct ethosu_device *edev;
+ struct file *file;
+ struct kref kref;
+ size_t capacity;
+ size_t offset;
+ size_t size;
+ void *cpu_addr;
+ dma_addr_t dma_addr;
+ dma_addr_t dma_addr_orig;
+};
+
+/****************************************************************************
+ * Functions
+ ****************************************************************************/
+
+/**
+ * ethosu_buffer_create() - Create buffer
+ *
+ * This function must be called in the context of a user space process.
+ *
+ * Return: fd on success, else error code.
+ */
+int ethosu_buffer_create(struct ethosu_device *edev,
+ size_t capacity);
+
+/**
+ * ethosu_buffer_get_from_fd() - Get buffer handle from fd
+ *
+ * This function must be called from a user space context.
+ *
+ * Return: Pointer on success, else ERR_PTR.
+ */
+struct ethosu_buffer *ethosu_buffer_get_from_fd(int fd);
+
+/**
+ * ethosu_buffer_get() - Put buffer
+ */
+void ethosu_buffer_get(struct ethosu_buffer *buf);
+
+/**
+ * ethosu_buffer_put() - Put buffer
+ */
+void ethosu_buffer_put(struct ethosu_buffer *buf);
+
+/**
+ * ethosu_buffer_resize() - Resize and validate buffer
+ *
+ * Return: 0 on success, else error code.
+ */
+int ethosu_buffer_resize(struct ethosu_buffer *buf,
+ size_t size,
+ size_t offset);
+
+#endif /* ETHOSU_BUFFER_H */