misc: mic: Add data structures for the VOP driver

/*

 * Intel MIC Platform Software Stack (MPSS)

 *

 * Copyright(c) 2016 Intel Corporation.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms 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.

 *

 * The full GNU General Public License is included in this distribution in

 * the file called "COPYING".

 *

 * Intel Virtio Over PCIe (VOP) driver.

 *

 */

#ifndef _VOP_MAIN_H_

#define _VOP_MAIN_H_

#include <linux/vringh.h>

#include <linux/virtio_config.h>

#include <linux/virtio.h>

#include <linux/miscdevice.h>

#include <linux/mic_common.h>

#include "../common/mic_dev.h"

#include "../bus/vop_bus.h"

/*

 * Note on endianness.

 * 1. Host can be both BE or LE

 * 2. Guest/card is LE. Host uses le_to_cpu to access desc/avail

 *    rings and ioreadXX/iowriteXX to access used ring.

 * 3. Device page exposed by host to guest contains LE values. Guest

 *    accesses these using ioreadXX/iowriteXX etc. This way in general we

 *    obey the virtio spec according to which guest works with native

 *    endianness and host is aware of guest endianness and does all

 *    required endianness conversion.

 * 4. Data provided from user space to guest (in ADD_DEVICE and

 *    CONFIG_CHANGE ioctl's) is not interpreted by the driver and should be

 *    in guest endianness.

 */

/*

 * vop_info - Allocated per invocation of VOP probe

 *

 * @vpdev: VOP device

 * @hotplug_work: Handle virtio device creation, deletion and configuration

 * @cookie: Cookie received upon requesting a virtio configuration interrupt

 * @h2c_config_db: The doorbell used by the peer to indicate a config change

 * @vdev_list: List of "active" virtio devices injected in the peer node

 * @vop_mutex: Synchronize access to the device page as well as serialize

 *             creation/deletion of virtio devices on the peer node

 * @dp: Peer device page information

 * @dbg: Debugfs entry

 * @dma_ch: The DMA channel used by this transport for data transfers.

 * @name: Name for this transport used in misc device creation.

 * @miscdev: The misc device registered.

 */

struct vop_info {

	struct vop_device *vpdev;

	struct work_struct hotplug_work;

	struct mic_irq *cookie;

	int h2c_config_db;

	struct list_head vdev_list;

	struct mutex vop_mutex;

	void __iomem *dp;

	struct dentry *dbg;

	struct dma_chan *dma_ch;

	char name[16];

	struct miscdevice miscdev;

};

/**

 * struct vop_vringh - Virtio ring host information.

 *

 * @vring: The VOP vring used for setting up user space mappings.

 * @vrh: The host VRINGH used for accessing the card vrings.

 * @riov: The VRINGH read kernel IOV.

 * @wiov: The VRINGH write kernel IOV.

 * @head: The VRINGH head index address passed to vringh_getdesc_kern(..).

 * @vr_mutex: Mutex for synchronizing access to the VRING.

 * @buf: Temporary kernel buffer used to copy in/out data

 * from/to the card via DMA.

 * @buf_da: dma address of buf.

 * @vdev: Back pointer to VOP virtio device for vringh_notify(..).

 */

struct vop_vringh {

	struct mic_vring vring;

	struct vringh vrh;

	struct vringh_kiov riov;

	struct vringh_kiov wiov;

	u16 head;

	struct mutex vr_mutex;

	void *buf;

	dma_addr_t buf_da;

	struct vop_vdev *vdev;

};

/**

 * struct vop_vdev - Host information for a card Virtio device.

 *

 * @virtio_id - Virtio device id.

 * @waitq - Waitqueue to allow ring3 apps to poll.

 * @vpdev - pointer to VOP bus device.

 * @poll_wake - Used for waking up threads blocked in poll.

 * @out_bytes - Debug stats for number of bytes copied from host to card.

 * @in_bytes - Debug stats for number of bytes copied from card to host.

 * @out_bytes_dma - Debug stats for number of bytes copied from host to card

 * using DMA.

 * @in_bytes_dma - Debug stats for number of bytes copied from card to host

 * using DMA.

 * @tx_len_unaligned - Debug stats for number of bytes copied to the card where

 * the transfer length did not have the required DMA alignment.

 * @tx_dst_unaligned - Debug stats for number of bytes copied where the

 * destination address on the card did not have the required DMA alignment.

 * @vvr - Store per VRING data structures.

 * @virtio_bh_work - Work struct used to schedule virtio bottom half handling.

 * @dd - Virtio device descriptor.

 * @dc - Virtio device control fields.

 * @list - List of Virtio devices.

 * @virtio_db - The doorbell used by the card to interrupt the host.

 * @virtio_cookie - The cookie returned while requesting interrupts.

 * @vi: Transport information.

 * @vdev_mutex: Mutex synchronizing virtio device injection,

 *              removal and data transfers.

 * @destroy: Track if a virtio device is being destroyed.

 * @deleted: The virtio device has been deleted.

 */

struct vop_vdev {

	int virtio_id;

	wait_queue_head_t waitq;

	struct vop_device *vpdev;

	int poll_wake;

	unsigned long out_bytes;

	unsigned long in_bytes;

	unsigned long out_bytes_dma;

	unsigned long in_bytes_dma;

	unsigned long tx_len_unaligned;

	unsigned long tx_dst_unaligned;

	unsigned long rx_dst_unaligned;

	struct vop_vringh vvr[MIC_MAX_VRINGS];

	struct work_struct virtio_bh_work;

	struct mic_device_desc *dd;

	struct mic_device_ctrl *dc;

	struct list_head list;

	int virtio_db;

	struct mic_irq *virtio_cookie;

	struct vop_info *vi;

	struct mutex vdev_mutex;

	struct completion destroy;

	bool deleted;

};

/* Helper API to check if a virtio device is running */

static inline bool vop_vdevup(struct vop_vdev *vdev)

{

	return !!vdev->dd->status;

}

void vop_init_debugfs(struct vop_info *vi);

void vop_exit_debugfs(struct vop_info *vi);

int vop_host_init(struct vop_info *vi);

void vop_host_uninit(struct vop_info *vi);

#endif