xref: /openbmc/qemu/include/hw/virtio/virtio-blk.h (revision d9d3aaea)
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 };
42 
43 struct VirtIOBlockDataPlane;
44 
45 struct VirtIOBlockReq;
46 typedef struct VirtIOBlock {
47     VirtIODevice parent_obj;
48     BlockBackend *blk;
49     VirtQueue *vq;
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     struct virtio_blk_inhdr *in;
66     struct virtio_blk_outhdr out;
67     QEMUIOVector qiov;
68     size_t in_len;
69     struct VirtIOBlockReq *next;
70     struct VirtIOBlockReq *mr_next;
71     BlockAcctCookie acct;
72 } VirtIOBlockReq;
73 
74 #define VIRTIO_BLK_MAX_MERGE_REQS 32
75 
76 typedef struct MultiReqBuffer {
77     VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS];
78     unsigned int num_reqs;
79     bool is_write;
80 } MultiReqBuffer;
81 
82 void virtio_blk_init_request(VirtIOBlock *s, VirtIOBlockReq *req);
83 void virtio_blk_free_request(VirtIOBlockReq *req);
84 
85 void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb);
86 
87 void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb);
88 
89 void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq);
90 
91 #endif
92