drivers/misc/mic/vop/vop_main.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Intel MIC Platform Software Stack (MPSS)
   4  *
   5  * Copyright(c) 2016 Intel Corporation.
   6  *
   7  * Intel Virtio Over PCIe (VOP) driver.
   8  */
   9 #ifndef _VOP_MAIN_H_
  10 #define _VOP_MAIN_H_
  11
  12 #include <linux/vringh.h>
  13 #include <linux/virtio_config.h>
  14 #include <linux/virtio.h>
  15 #include <linux/miscdevice.h>
  16
  17 #include <linux/mic_common.h>
  18 #include "../common/mic_dev.h"
  19
  20 #include "../bus/vop_bus.h"
  21
  22 /*
  23  * Note on endianness.
  24  * 1. Host can be both BE or LE
  25  * 2. Guest/card is LE. Host uses le_to_cpu to access desc/avail
  26  *    rings and ioreadXX/iowriteXX to access used ring.
  27  * 3. Device page exposed by host to guest contains LE values. Guest
  28  *    accesses these using ioreadXX/iowriteXX etc. This way in general we
  29  *    obey the virtio spec according to which guest works with native
  30  *    endianness and host is aware of guest endianness and does all
  31  *    required endianness conversion.
  32  * 4. Data provided from user space to guest (in ADD_DEVICE and
  33  *    CONFIG_CHANGE ioctl's) is not interpreted by the driver and should be
  34  *    in guest endianness.
  35  */
  36
  37 /*
  38  * vop_info - Allocated per invocation of VOP probe
  39  *
  40  * @vpdev: VOP device
  41  * @hotplug_work: Handle virtio device creation, deletion and configuration
  42  * @cookie: Cookie received upon requesting a virtio configuration interrupt
  43  * @h2c_config_db: The doorbell used by the peer to indicate a config change
  44  * @vdev_list: List of "active" virtio devices injected in the peer node
  45  * @vop_mutex: Synchronize access to the device page as well as serialize
  46  *             creation/deletion of virtio devices on the peer node
  47  * @dp: Peer device page information
  48  * @dbg: Debugfs entry
  49  * @dma_ch: The DMA channel used by this transport for data transfers.
  50  * @name: Name for this transport used in misc device creation.
  51  * @miscdev: The misc device registered.
  52  */
  53 struct vop_info {
  54         struct vop_device *vpdev;
  55         struct work_struct hotplug_work;
  56         struct mic_irq *cookie;
  57         int h2c_config_db;
  58         struct list_head vdev_list;
  59         struct mutex vop_mutex;
  60         void __iomem *dp;
  61         struct dentry *dbg;
  62         struct dma_chan *dma_ch;
  63         char name[16];
  64         struct miscdevice miscdev;
  65 };
  66
  67 /**
  68  * struct vop_vringh - Virtio ring host information.
  69  *
  70  * @vring: The VOP vring used for setting up user space mappings.
  71  * @vrh: The host VRINGH used for accessing the card vrings.
  72  * @riov: The VRINGH read kernel IOV.
  73  * @wiov: The VRINGH write kernel IOV.
  74  * @head: The VRINGH head index address passed to vringh_getdesc_kern(..).
  75  * @vr_mutex: Mutex for synchronizing access to the VRING.
  76  * @buf: Temporary kernel buffer used to copy in/out data
  77  * from/to the card via DMA.
  78  * @buf_da: dma address of buf.
  79  * @vdev: Back pointer to VOP virtio device for vringh_notify(..).
  80  */
  81 struct vop_vringh {
  82         struct mic_vring vring;
  83         struct vringh vrh;
  84         struct vringh_kiov riov;
  85         struct vringh_kiov wiov;
  86         u16 head;
  87         struct mutex vr_mutex;
  88         void *buf;
  89         dma_addr_t buf_da;
  90         struct vop_vdev *vdev;
  91 };
  92
  93 /**
  94  * struct vop_vdev - Host information for a card Virtio device.
  95  *
  96  * @virtio_id - Virtio device id.
  97  * @waitq - Waitqueue to allow ring3 apps to poll.
  98  * @vpdev - pointer to VOP bus device.
  99  * @poll_wake - Used for waking up threads blocked in poll.
 100  * @out_bytes - Debug stats for number of bytes copied from host to card.
 101  * @in_bytes - Debug stats for number of bytes copied from card to host.
 102  * @out_bytes_dma - Debug stats for number of bytes copied from host to card
 103  * using DMA.
 104  * @in_bytes_dma - Debug stats for number of bytes copied from card to host
 105  * using DMA.
 106  * @tx_len_unaligned - Debug stats for number of bytes copied to the card where
 107  * the transfer length did not have the required DMA alignment.
 108  * @tx_dst_unaligned - Debug stats for number of bytes copied where the
 109  * destination address on the card did not have the required DMA alignment.
 110  * @vvr - Store per VRING data structures.
 111  * @virtio_bh_work - Work struct used to schedule virtio bottom half handling.
 112  * @dd - Virtio device descriptor.
 113  * @dc - Virtio device control fields.
 114  * @list - List of Virtio devices.
 115  * @virtio_db - The doorbell used by the card to interrupt the host.
 116  * @virtio_cookie - The cookie returned while requesting interrupts.
 117  * @vi: Transport information.
 118  * @vdev_mutex: Mutex synchronizing virtio device injection,
 119  *              removal and data transfers.
 120  * @destroy: Track if a virtio device is being destroyed.
 121  * @deleted: The virtio device has been deleted.
 122  */
 123 struct vop_vdev {
 124         int virtio_id;
 125         wait_queue_head_t waitq;
 126         struct vop_device *vpdev;
 127         int poll_wake;
 128         unsigned long out_bytes;
 129         unsigned long in_bytes;
 130         unsigned long out_bytes_dma;
 131         unsigned long in_bytes_dma;
 132         unsigned long tx_len_unaligned;
 133         unsigned long tx_dst_unaligned;
 134         unsigned long rx_dst_unaligned;
 135         struct vop_vringh vvr[MIC_MAX_VRINGS];
 136         struct work_struct virtio_bh_work;
 137         struct mic_device_desc *dd;
 138         struct mic_device_ctrl *dc;
 139         struct list_head list;
 140         int virtio_db;
 141         struct mic_irq *virtio_cookie;
 142         struct vop_info *vi;
 143         struct mutex vdev_mutex;
 144         struct completion destroy;
 145         bool deleted;
 146 };
 147
 148 /* Helper API to check if a virtio device is running */
 149 static inline bool vop_vdevup(struct vop_vdev *vdev)
 150 {
 151         return !!vdev->dd->status;
 152 }
 153
 154 void vop_init_debugfs(struct vop_info *vi);
 155 void vop_exit_debugfs(struct vop_info *vi);
 156 int vop_host_init(struct vop_info *vi);
 157 void vop_host_uninit(struct vop_info *vi);
 158 #endif