LXR linux/drivers/misc/mic/vop/vop

   1/*
   2 * Intel MIC Platform Software Stack (MPSS)
   3 *
   4 * Copyright(c) 2016 Intel Corporation.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License, version 2, as
   8 * published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it will be useful, but
  11 * WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13 * General Public License for more details.
  14 *
  15 * The full GNU General Public License is included in this distribution in
  16 * the file called "COPYING".
  17 *
  18 * Intel Virtio Over PCIe (VOP) driver.
  19 *
  20 */
  21#ifndef _VOP_MAIN_H_
  22#define _VOP_MAIN_H_
  23
  24#include <linux/vringh.h>
  25#include <linux/virtio_config.h>
  26#include <linux/virtio.h>
  27#include <linux/miscdevice.h>
  28
  29#include <linux/mic_common.h>
  30#include "../common/mic_dev.h"
  31
  32#include "../bus/vop_bus.h"
  33
  34/*
  35 * Note on endianness.
  36 * 1. Host can be both BE or LE
  37 * 2. Guest/card is LE. Host uses le_to_cpu to access desc/avail
  38 *    rings and ioreadXX/iowriteXX to access used ring.
  39 * 3. Device page exposed by host to guest contains LE values. Guest
  40 *    accesses these using ioreadXX/iowriteXX etc. This way in general we
  41 *    obey the virtio spec according to which guest works with native
  42 *    endianness and host is aware of guest endianness and does all
  43 *    required endianness conversion.
  44 * 4. Data provided from user space to guest (in ADD_DEVICE and
  45 *    CONFIG_CHANGE ioctl's) is not interpreted by the driver and should be
  46 *    in guest endianness.
  47 */
  48
  49/*
  50 * vop_info - Allocated per invocation of VOP probe
  51 *
  52 * @vpdev: VOP device
  53 * @hotplug_work: Handle virtio device creation, deletion and configuration
  54 * @cookie: Cookie received upon requesting a virtio configuration interrupt
  55 * @h2c_config_db: The doorbell used by the peer to indicate a config change
  56 * @vdev_list: List of "active" virtio devices injected in the peer node
  57 * @vop_mutex: Synchronize access to the device page as well as serialize
  58 *             creation/deletion of virtio devices on the peer node
  59 * @dp: Peer device page information
  60 * @dbg: Debugfs entry
  61 * @dma_ch: The DMA channel used by this transport for data transfers.
  62 * @name: Name for this transport used in misc device creation.
  63 * @miscdev: The misc device registered.
  64 */
  65struct vop_info {
  66        struct vop_device *vpdev;
  67        struct work_struct hotplug_work;
  68        struct mic_irq *cookie;
  69        int h2c_config_db;
  70        struct list_head vdev_list;
  71        struct mutex vop_mutex;
  72        void __iomem *dp;
  73        struct dentry *dbg;
  74        struct dma_chan *dma_ch;
  75        char name[16];
  76        struct miscdevice miscdev;
  77};
  78
  79/**
  80 * struct vop_vringh - Virtio ring host information.
  81 *
  82 * @vring: The VOP vring used for setting up user space mappings.
  83 * @vrh: The host VRINGH used for accessing the card vrings.
  84 * @riov: The VRINGH read kernel IOV.
  85 * @wiov: The VRINGH write kernel IOV.
  86 * @head: The VRINGH head index address passed to vringh_getdesc_kern(..).
  87 * @vr_mutex: Mutex for synchronizing access to the VRING.
  88 * @buf: Temporary kernel buffer used to copy in/out data
  89 * from/to the card via DMA.
  90 * @buf_da: dma address of buf.
  91 * @vdev: Back pointer to VOP virtio device for vringh_notify(..).
  92 */
  93struct vop_vringh {
  94        struct mic_vring vring;
  95        struct vringh vrh;
  96        struct vringh_kiov riov;
  97        struct vringh_kiov wiov;
  98        u16 head;
  99        struct mutex vr_mutex;
 100        void *buf;
 101        dma_addr_t buf_da;
 102        struct vop_vdev *vdev;
 103};
 104
 105/**
 106 * struct vop_vdev - Host information for a card Virtio device.
 107 *
 108 * @virtio_id - Virtio device id.
 109 * @waitq - Waitqueue to allow ring3 apps to poll.
 110 * @vpdev - pointer to VOP bus device.
 111 * @poll_wake - Used for waking up threads blocked in poll.
 112 * @out_bytes - Debug stats for number of bytes copied from host to card.
 113 * @in_bytes - Debug stats for number of bytes copied from card to host.
 114 * @out_bytes_dma - Debug stats for number of bytes copied from host to card
 115 * using DMA.
 116 * @in_bytes_dma - Debug stats for number of bytes copied from card to host
 117 * using DMA.
 118 * @tx_len_unaligned - Debug stats for number of bytes copied to the card where
 119 * the transfer length did not have the required DMA alignment.
 120 * @tx_dst_unaligned - Debug stats for number of bytes copied where the
 121 * destination address on the card did not have the required DMA alignment.
 122 * @vvr - Store per VRING data structures.
 123 * @virtio_bh_work - Work struct used to schedule virtio bottom half handling.
 124 * @dd - Virtio device descriptor.
 125 * @dc - Virtio device control fields.
 126 * @list - List of Virtio devices.
 127 * @virtio_db - The doorbell used by the card to interrupt the host.
 128 * @virtio_cookie - The cookie returned while requesting interrupts.
 129 * @vi: Transport information.
 130 * @vdev_mutex: Mutex synchronizing virtio device injection,
 131 *              removal and data transfers.
 132 * @destroy: Track if a virtio device is being destroyed.
 133 * @deleted: The virtio device has been deleted.
 134 */
 135struct vop_vdev {
 136        int virtio_id;
 137        wait_queue_head_t waitq;
 138        struct vop_device *vpdev;
 139        int poll_wake;
 140        unsigned long out_bytes;
 141        unsigned long in_bytes;
 142        unsigned long out_bytes_dma;
 143        unsigned long in_bytes_dma;
 144        unsigned long tx_len_unaligned;
 145        unsigned long tx_dst_unaligned;
 146        unsigned long rx_dst_unaligned;
 147        struct vop_vringh vvr[MIC_MAX_VRINGS];
 148        struct work_struct virtio_bh_work;
 149        struct mic_device_desc *dd;
 150        struct mic_device_ctrl *dc;
 151        struct list_head list;
 152        int virtio_db;
 153        struct mic_irq *virtio_cookie;
 154        struct vop_info *vi;
 155        struct mutex vdev_mutex;
 156        struct completion destroy;
 157        bool deleted;
 158};
 159
 160/* Helper API to check if a virtio device is running */
 161static inline bool vop_vdevup(struct vop_vdev *vdev)
 162{
 163        return !!vdev->dd->status;
 164}
 165
 166void vop_init_debugfs(struct vop_info *vi);
 167void vop_exit_debugfs(struct vop_info *vi);
 168int vop_host_init(struct vop_info *vi);
 169void vop_host_uninit(struct vop_info *vi);
 170#endif
 171