Linux kernel mirror (for testing)
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1#ifndef _LINUX_VIRTIO_BLK_H
2#define _LINUX_VIRTIO_BLK_H
3/* This header is BSD licensed so anyone can use the definitions to implement
4 * compatible drivers/servers. */
5#include <linux/types.h>
6#include <linux/virtio_config.h>
7
8/* The ID for virtio_block */
9#define VIRTIO_ID_BLOCK 2
10
11/* Feature bits */
12#define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */
13#define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */
14#define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */
15#define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */
16#define VIRTIO_BLK_F_RO 5 /* Disk is read-only */
17#define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/
18#define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */
19#define VIRTIO_BLK_F_IDENTIFY 8 /* ATA IDENTIFY supported */
20
21#define VIRTIO_BLK_ID_BYTES (sizeof(__u16[256])) /* IDENTIFY DATA */
22
23struct virtio_blk_config {
24 /* The capacity (in 512-byte sectors). */
25 __u64 capacity;
26 /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */
27 __u32 size_max;
28 /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
29 __u32 seg_max;
30 /* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */
31 struct virtio_blk_geometry {
32 __u16 cylinders;
33 __u8 heads;
34 __u8 sectors;
35 } geometry;
36 /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */
37 __u32 blk_size;
38 __u8 identify[VIRTIO_BLK_ID_BYTES];
39} __attribute__((packed));
40
41/* These two define direction. */
42#define VIRTIO_BLK_T_IN 0
43#define VIRTIO_BLK_T_OUT 1
44
45/* This bit says it's a scsi command, not an actual read or write. */
46#define VIRTIO_BLK_T_SCSI_CMD 2
47
48/* Barrier before this op. */
49#define VIRTIO_BLK_T_BARRIER 0x80000000
50
51/* This is the first element of the read scatter-gather list. */
52struct virtio_blk_outhdr {
53 /* VIRTIO_BLK_T* */
54 __u32 type;
55 /* io priority. */
56 __u32 ioprio;
57 /* Sector (ie. 512 byte offset) */
58 __u64 sector;
59};
60
61struct virtio_scsi_inhdr {
62 __u32 errors;
63 __u32 data_len;
64 __u32 sense_len;
65 __u32 residual;
66};
67
68/* And this is the final byte of the write scatter-gather list. */
69#define VIRTIO_BLK_S_OK 0
70#define VIRTIO_BLK_S_IOERR 1
71#define VIRTIO_BLK_S_UNSUPP 2
72#endif /* _LINUX_VIRTIO_BLK_H */