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/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
19struct virtio_blk_config
20{
21 /* The capacity (in 512-byte sectors). */
22 __u64 capacity;
23 /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */
24 __u32 size_max;
25 /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
26 __u32 seg_max;
27 /* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */
28 struct virtio_blk_geometry {
29 __u16 cylinders;
30 __u8 heads;
31 __u8 sectors;
32 } geometry;
33 /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */
34 __u32 blk_size;
35} __attribute__((packed));
36
37/* These two define direction. */
38#define VIRTIO_BLK_T_IN 0
39#define VIRTIO_BLK_T_OUT 1
40
41/* This bit says it's a scsi command, not an actual read or write. */
42#define VIRTIO_BLK_T_SCSI_CMD 2
43
44/* Barrier before this op. */
45#define VIRTIO_BLK_T_BARRIER 0x80000000
46
47/* This is the first element of the read scatter-gather list. */
48struct virtio_blk_outhdr
49{
50 /* VIRTIO_BLK_T* */
51 __u32 type;
52 /* io priority. */
53 __u32 ioprio;
54 /* Sector (ie. 512 byte offset) */
55 __u64 sector;
56};
57
58/* And this is the final byte of the write scatter-gather list. */
59#define VIRTIO_BLK_S_OK 0
60#define VIRTIO_BLK_S_IOERR 1
61#define VIRTIO_BLK_S_UNSUPP 2
62#endif /* _LINUX_VIRTIO_BLK_H */