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 #include "qapi/qapi-types-virtio.h"
  25
  26 #define TYPE_VIRTIO_BLK "virtio-blk-device"
  27 OBJECT_DECLARE_SIMPLE_TYPE(VirtIOBlock, VIRTIO_BLK)
  28
  29 /* This is the last element of the write scatter-gather list */
  30 struct virtio_blk_inhdr
  31 {
  32     unsigned char status;
  33 };
  34
  35 #define VIRTIO_BLK_AUTO_NUM_QUEUES UINT16_MAX
  36
  37 struct VirtIOBlkConf
  38 {
  39     BlockConf conf;
  40     IOThread *iothread;
  41     IOThreadVirtQueueMappingList *iothread_vq_mapping_list;
  42     char *serial;
  43     uint32_t request_merging;
  44     uint16_t num_queues;
  45     uint16_t queue_size;
  46     bool seg_max_adjust;
  47     bool report_discard_granularity;
  48     uint32_t max_discard_sectors;
  49     uint32_t max_write_zeroes_sectors;
  50     bool x_enable_wce_if_config_wce;
  51 };
  52
  53 struct VirtIOBlockReq;
  54 struct VirtIOBlock {
  55     VirtIODevice parent_obj;
  56     BlockBackend *blk;
  57     QemuMutex rq_lock;
  58     struct VirtIOBlockReq *rq; /* protected by rq_lock */
  59     VirtIOBlkConf conf;
  60     unsigned short sector_mask;
  61     bool original_wce;
  62     VMChangeStateEntry *change;
  63     bool ioeventfd_disabled;
  64     bool ioeventfd_started;
  65     bool ioeventfd_starting;
  66     bool ioeventfd_stopping;
  67
  68     /*
  69      * The AioContext for each virtqueue. The BlockDriverState will use the
  70      * first element as its AioContext.
  71      */
  72     AioContext **vq_aio_context;
  73
  74     uint64_t host_features;
  75     size_t config_size;
  76     BlockRAMRegistrar blk_ram_registrar;
  77 };
  78
  79 typedef struct VirtIOBlockReq {
  80     VirtQueueElement elem;
  81     int64_t sector_num;
  82     VirtIOBlock *dev;
  83     VirtQueue *vq;
  84     IOVDiscardUndo inhdr_undo;
  85     IOVDiscardUndo outhdr_undo;
  86     struct virtio_blk_inhdr *in;
  87     struct virtio_blk_outhdr out;
  88     QEMUIOVector qiov;
  89     size_t in_len;
  90     struct VirtIOBlockReq *next;
  91     struct VirtIOBlockReq *mr_next;
  92     BlockAcctCookie acct;
  93 } VirtIOBlockReq;
  94
  95 #define VIRTIO_BLK_MAX_MERGE_REQS 32
  96
  97 typedef struct MultiReqBuffer {
  98     VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS];
  99     unsigned int num_reqs;
 100     bool is_write;
 101 } MultiReqBuffer;
 102
 103 void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq);
 104
 105 #endif