Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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/virtio_config.h>
6
7/* The ID for virtio_block */
8#define VIRTIO_ID_BLOCK 2
9
10/* Feature bits */
11#define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */
12#define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */
13#define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */
14#define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */
15#define VIRTIO_BLK_F_RO 5 /* Disk is read-only */
16#define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/
17
18struct virtio_blk_config
19{
20 /* The capacity (in 512-byte sectors). */
21 __u64 capacity;
22 /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */
23 __u32 size_max;
24 /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
25 __u32 seg_max;
26 /* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */
27 struct virtio_blk_geometry {
28 __u16 cylinders;
29 __u8 heads;
30 __u8 sectors;
31 } geometry;
32 /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */
33 __u32 blk_size;
34} __attribute__((packed));
35
36/* These two define direction. */
37#define VIRTIO_BLK_T_IN 0
38#define VIRTIO_BLK_T_OUT 1
39
40/* This bit says it's a scsi command, not an actual read or write. */
41#define VIRTIO_BLK_T_SCSI_CMD 2
42
43/* Barrier before this op. */
44#define VIRTIO_BLK_T_BARRIER 0x80000000
45
46/* This is the first element of the read scatter-gather list. */
47struct virtio_blk_outhdr
48{
49 /* VIRTIO_BLK_T* */
50 __u32 type;
51 /* io priority. */
52 __u32 ioprio;
53 /* Sector (ie. 512 byte offset) */
54 __u64 sector;
55};
56
57/* And this is the final byte of the write scatter-gather list. */
58#define VIRTIO_BLK_S_OK 0
59#define VIRTIO_BLK_S_IOERR 1
60#define VIRTIO_BLK_S_UNSUPP 2
61#endif /* _LINUX_VIRTIO_BLK_H */