LXR qemu/include/hw/virtio/virtio-blk.h

   1/*
   2 * Virtio Block Device
   3 *
   4 * Copyright IBM, Corp. 2007
   5 *
   6 * Authors:
   7 *  Anthony Liguori   <aliguori@us.ibm.com>
   8 *
   9 * This work is licensed under the terms of the GNU GPL, version 2.  See
  10 * the COPYING file in the top-level directory.
  11 *
  12 */
  13
  14#ifndef QEMU_VIRTIO_BLK_H
  15#define QEMU_VIRTIO_BLK_H
  16
  17#include "standard-headers/linux/virtio_blk.h"
  18#include "hw/virtio/virtio.h"
  19#include "hw/block/block.h"
  20#include "sysemu/iothread.h"
  21#include "sysemu/block-backend.h"
  22#include "sysemu/block-ram-registrar.h"
  23#include "qom/object.h"
  24
  25#define TYPE_VIRTIO_BLK "virtio-blk-device"
  26OBJECT_DECLARE_SIMPLE_TYPE(VirtIOBlock, VIRTIO_BLK)
  27
  28/* This is the last element of the write scatter-gather list */
  29struct virtio_blk_inhdr
  30{
  31    unsigned char status;
  32};
  33
  34#define VIRTIO_BLK_AUTO_NUM_QUEUES UINT16_MAX
  35
  36struct VirtIOBlkConf
  37{
  38    BlockConf conf;
  39    IOThread *iothread;
  40    char *serial;
  41    uint32_t request_merging;
  42    uint16_t num_queues;
  43    uint16_t queue_size;
  44    bool seg_max_adjust;
  45    bool report_discard_granularity;
  46    uint32_t max_discard_sectors;
  47    uint32_t max_write_zeroes_sectors;
  48    bool x_enable_wce_if_config_wce;
  49};
  50
  51struct VirtIOBlockDataPlane;
  52
  53struct VirtIOBlockReq;
  54struct VirtIOBlock {
  55    VirtIODevice parent_obj;
  56    BlockBackend *blk;
  57    void *rq;
  58    QEMUBH *bh;
  59    VirtIOBlkConf conf;
  60    unsigned short sector_mask;
  61    bool original_wce;
  62    VMChangeStateEntry *change;
  63    bool dataplane_disabled;
  64    bool dataplane_started;
  65    struct VirtIOBlockDataPlane *dataplane;
  66    uint64_t host_features;
  67    size_t config_size;
  68    BlockRAMRegistrar blk_ram_registrar;
  69};
  70
  71typedef struct VirtIOBlockReq {
  72    VirtQueueElement elem;
  73    int64_t sector_num;
  74    VirtIOBlock *dev;
  75    VirtQueue *vq;
  76    IOVDiscardUndo inhdr_undo;
  77    IOVDiscardUndo outhdr_undo;
  78    struct virtio_blk_inhdr *in;
  79    struct virtio_blk_outhdr out;
  80    QEMUIOVector qiov;
  81    size_t in_len;
  82    struct VirtIOBlockReq *next;
  83    struct VirtIOBlockReq *mr_next;
  84    BlockAcctCookie acct;
  85} VirtIOBlockReq;
  86
  87#define VIRTIO_BLK_MAX_MERGE_REQS 32
  88
  89typedef struct MultiReqBuffer {
  90    VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS];
  91    unsigned int num_reqs;
  92    bool is_write;
  93} MultiReqBuffer;
  94
  95void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq);
  96void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh);
  97
  98#endif
  99