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