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 "qom/object.h"
  23
  24#define TYPE_VIRTIO_BLK "virtio-blk-device"
  25OBJECT_DECLARE_SIMPLE_TYPE(VirtIOBlock, VIRTIO_BLK)
  26
  27/* This is the last element of the write scatter-gather list */
  28struct virtio_blk_inhdr
  29{
  30    unsigned char status;
  31};
  32
  33#define VIRTIO_BLK_AUTO_NUM_QUEUES UINT16_MAX
  34
  35struct VirtIOBlkConf
  36{
  37    BlockConf conf;
  38    IOThread *iothread;
  39    char *serial;
  40    uint32_t request_merging;
  41    uint16_t num_queues;
  42    uint16_t queue_size;
  43    bool seg_max_adjust;
  44    uint32_t max_discard_sectors;
  45    uint32_t max_write_zeroes_sectors;
  46    bool x_enable_wce_if_config_wce;
  47};
  48
  49struct VirtIOBlockDataPlane;
  50
  51struct VirtIOBlockReq;
  52struct VirtIOBlock {
  53    VirtIODevice parent_obj;
  54    BlockBackend *blk;
  55    void *rq;
  56    QEMUBH *bh;
  57    VirtIOBlkConf conf;
  58    unsigned short sector_mask;
  59    bool original_wce;
  60    VMChangeStateEntry *change;
  61    bool dataplane_disabled;
  62    bool dataplane_started;
  63    struct VirtIOBlockDataPlane *dataplane;
  64    uint64_t host_features;
  65    size_t config_size;
  66};
  67
  68typedef struct VirtIOBlockReq {
  69    VirtQueueElement elem;
  70    int64_t sector_num;
  71    VirtIOBlock *dev;
  72    VirtQueue *vq;
  73    IOVDiscardUndo inhdr_undo;
  74    IOVDiscardUndo outhdr_undo;
  75    struct virtio_blk_inhdr *in;
  76    struct virtio_blk_outhdr out;
  77    QEMUIOVector qiov;
  78    size_t in_len;
  79    struct VirtIOBlockReq *next;
  80    struct VirtIOBlockReq *mr_next;
  81    BlockAcctCookie acct;
  82} VirtIOBlockReq;
  83
  84#define VIRTIO_BLK_MAX_MERGE_REQS 32
  85
  86typedef struct MultiReqBuffer {
  87    VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS];
  88    unsigned int num_reqs;
  89    bool is_write;
  90} MultiReqBuffer;
  91
  92bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq);
  93void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh);
  94
  95#endif
  96