xref: /qemu/include/hw/virtio/virtio-blk.h (revision 6402cbbb)
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     void *rq;
51     QEMUBH *bh;
52     VirtIOBlkConf conf;
53     unsigned short sector_mask;
54     bool original_wce;
55     VMChangeStateEntry *change;
56     bool dataplane_disabled;
57     bool dataplane_started;
58     struct VirtIOBlockDataPlane *dataplane;
59 } VirtIOBlock;
60 
61 typedef struct VirtIOBlockReq {
62     VirtQueueElement elem;
63     int64_t sector_num;
64     VirtIOBlock *dev;
65     VirtQueue *vq;
66     struct virtio_blk_inhdr *in;
67     struct virtio_blk_outhdr out;
68     QEMUIOVector qiov;
69     size_t in_len;
70     struct VirtIOBlockReq *next;
71     struct VirtIOBlockReq *mr_next;
72     BlockAcctCookie acct;
73 } VirtIOBlockReq;
74 
75 #define VIRTIO_BLK_MAX_MERGE_REQS 32
76 
77 typedef struct MultiReqBuffer {
78     VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS];
79     unsigned int num_reqs;
80     bool is_write;
81 } MultiReqBuffer;
82 
83 bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq);
84 
85 #endif
86