linux/drivers/misc/mic/host/mic_virtio.h

139 lines
4.4 KiB
C

/*
* Intel MIC Platform Software Stack (MPSS)
*
* Copyright(c) 2013 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 MIC Host driver.
*
*/
#ifndef MIC_VIRTIO_H
#define MIC_VIRTIO_H
#include <linux/virtio_config.h>
#include <linux/mic_ioctl.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.
*/
/**
* struct mic_vringh - Virtio ring host information.
*
* @vring: The MIC 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.
* @mvdev: Back pointer to MIC virtio device for vringh_notify(..).
*/
struct mic_vringh {
struct mic_vring vring;
struct vringh vrh;
struct vringh_kiov riov;
struct vringh_kiov wiov;
u16 head;
struct mutex vr_mutex;
struct mic_vdev *mvdev;
};
/**
* struct mic_vdev - Host information for a card Virtio device.
*
* @virtio_id - Virtio device id.
* @waitq - Waitqueue to allow ring3 apps to poll.
* @mdev - Back pointer to host MIC 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.
* @mvr - 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.
*/
struct mic_vdev {
int virtio_id;
wait_queue_head_t waitq;
struct mic_device *mdev;
int poll_wake;
unsigned long out_bytes;
unsigned long in_bytes;
struct mic_vringh mvr[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;
};
void mic_virtio_uninit(struct mic_device *mdev);
int mic_virtio_add_device(struct mic_vdev *mvdev,
void __user *argp);
void mic_virtio_del_device(struct mic_vdev *mvdev);
int mic_virtio_config_change(struct mic_vdev *mvdev,
void __user *argp);
int mic_virtio_copy_desc(struct mic_vdev *mvdev,
struct mic_copy_desc *request);
void mic_virtio_reset_devices(struct mic_device *mdev);
void mic_bh_handler(struct work_struct *work);
/* Helper API to obtain the MIC PCIe device */
static inline struct device *mic_dev(struct mic_vdev *mvdev)
{
return mvdev->mdev->sdev->parent;
}
/* Helper API to check if a virtio device is initialized */
static inline int mic_vdev_inited(struct mic_vdev *mvdev)
{
/* Device has not been created yet */
if (!mvdev->dd || !mvdev->dd->type) {
dev_err(mic_dev(mvdev), "%s %d err %d\n",
__func__, __LINE__, -EINVAL);
return -EINVAL;
}
/* Device has been removed/deleted */
if (mvdev->dd->type == -1) {
dev_err(mic_dev(mvdev), "%s %d err %d\n",
__func__, __LINE__, -ENODEV);
return -ENODEV;
}
return 0;
}
/* Helper API to check if a virtio device is running */
static inline bool mic_vdevup(struct mic_vdev *mvdev)
{
return !!mvdev->dd->status;
}
#endif