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    bool report_discard_granularity;
  45    uint32_t max_discard_sectors;
  46    uint32_t max_write_zeroes_sectors;
  47    bool x_enable_wce_if_config_wce;
  48};
  49
  50struct VirtIOBlockDataPlane;
  51
  52struct VirtIOBlockReq;
  53struct VirtIOBlock {
  54    VirtIODevice parent_obj;
  55    BlockBackend *blk;
  56    void *rq;
  57    QEMUBH *bh;
  58    VirtIOBlkConf conf;
  59    unsigned short sector_mask;
  60    bool original_wce;
  61    VMChangeStateEntry *change;
  62    bool dataplane_disabled;
  63    bool dataplane_started;
  64    struct VirtIOBlockDataPlane *dataplane;
  65    uint64_t host_features;
  66    size_t config_size;
  67};
  68
  69typedef struct VirtIOBlockReq {
  70    VirtQueueElement elem;
  71    int64_t sector_num;
  72    VirtIOBlock *dev;
  73    VirtQueue *vq;
  74    IOVDiscardUndo inhdr_undo;
  75    IOVDiscardUndo outhdr_undo;
  76    struct virtio_blk_inhdr *in;
  77    struct virtio_blk_outhdr out;
  78    QEMUIOVector qiov;
  79    size_t in_len;
  80    struct VirtIOBlockReq *next;
  81    struct VirtIOBlockReq *mr_next;
  82    BlockAcctCookie acct;
  83} VirtIOBlockReq;
  84
  85#define VIRTIO_BLK_MAX_MERGE_REQS 32
  86
  87typedef struct MultiReqBuffer {
  88    VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS];
  89    unsigned int num_reqs;
  90    bool is_write;
  91} MultiReqBuffer;
  92
  93bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq);
  94void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh);
  95
  96#endif
  97