ANDROID: goldfish_pipe: An implementation of more parallel pipe

[firefly-linux-kernel-4.4.55.git] / drivers / platform / goldfish / goldfish_pipe.h

diff --git a/drivers/platform/goldfish/goldfish_pipe.h b/drivers/platform/goldfish/goldfish_pipe.h
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+++ b/drivers/platform/goldfish/goldfish_pipe.h
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+/*
+ * Copyright (C) 2016 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+#ifndef GOLDFISH_PIPE_H
+#define GOLDFISH_PIPE_H
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/miscdevice.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/bitops.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/goldfish.h>
+#include <linux/mm.h>
+#include <linux/acpi.h>
+
+
+/* Initialize the legacy version of the pipe device driver */
+int goldfish_pipe_device_init_v1(struct platform_device *pdev);
+
+/* Deinitialize the legacy version of the pipe device driver */
+void goldfish_pipe_device_deinit_v1(struct platform_device *pdev);
+
+/* Forward declarations for the device struct */
+struct goldfish_pipe;
+struct goldfish_pipe_device_buffers;
+
+/* The global driver data. Holds a reference to the i/o page used to
+ * communicate with the emulator, and a wake queue for blocked tasks
+ * waiting to be awoken.
+ */
+struct goldfish_pipe_dev {
+       /*
+        * Global device spinlock. Protects the following members:
+        *  - pipes, pipes_capacity
+        *  - [*pipes, *pipes + pipes_capacity) - array data
+        *  - first_signalled_pipe,
+        *      goldfish_pipe::prev_signalled,
+        *      goldfish_pipe::next_signalled,
+        *      goldfish_pipe::signalled_flags - all singnalled-related fields,
+        *                                       in all allocated pipes
+        *  - open_command_params - PIPE_CMD_OPEN-related buffers
+        *
+        * It looks like a lot of different fields, but the trick is that the only
+        * operation that happens often is the signalled pipes array manipulation.
+        * That's why it's OK for now to keep the rest of the fields under the same
+        * lock. If we notice too much contention because of PIPE_CMD_OPEN,
+        * then we should add a separate lock there.
+        */
+       spinlock_t lock;
+
+       /*
+        * Array of the pipes of |pipes_capacity| elements,
+        * indexed by goldfish_pipe::id
+        */
+       struct goldfish_pipe **pipes;
+       u32 pipes_capacity;
+
+       /* Pointers to the buffers host uses for interaction with this driver */
+       struct goldfish_pipe_dev_buffers *buffers;
+
+       /* Head of a doubly linked list of signalled pipes */
+       struct goldfish_pipe *first_signalled_pipe;
+
+       /* Some device-specific data */
+       int irq;
+       int version;
+       unsigned char __iomem *base;
+
+       /* v1-specific access parameters */
+       struct access_params *aps;
+};
+
+extern struct goldfish_pipe_dev pipe_dev[1];
+
+#endif /* GOLDFISH_PIPE_H */