xref: /openbsd/share/man/man4/vscsi.4 (revision 09467b48)
1.\"	$OpenBSD: vscsi.4,v 1.14 2017/09/12 15:06:20 schwarze Exp $
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3.\" Copyright (c) 2008 David Gwynne <dlg@openbsd.org>
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17.Dd $Mdocdate: September 12 2017 $
18.Dt VSCSI 4
19.Os
20.Sh NAME
21.Nm vscsi
22.Nd virtual SCSI controller
23.Sh SYNOPSIS
24.Cd "vscsi0 at root"
25.Pp
26.In sys/types.h
27.In sys/ioctl.h
28.In scsi/scsi_all.h
29.In dev/vscsivar.h
30.Sh DESCRIPTION
31The
32.Nm
33device takes commands from the kernel SCSI midlayer and makes them available
34to userland for handling.
35Using this interface it is possible to implement virtual SCSI devices that are
36usable by the kernel.
37.Pp
38The following
39.Xr ioctl 2
40commands are provided to allow userland to dequeue SCSI commands and reply to
41them:
42.Pp
43.Bl -tag -width Ds -compact
44.It Dv VSCSI_I2T Fa "struct vscsi_ioc_i2t *"
45Dequeue a SCSI command.
46If no SCSI commands are available to dequeue,
47.Xr ioctl 2
48will fail and set
49.Va errno
50to
51.Dv EAGAIN .
52.Pp
53When one or more SCSI commands are available to dequeue,
54.Xr select 2
55will indicate the descriptor as ready to read.
56.Bd -literal -offset indent
57struct vscsi_ioc_i2t {
58	int			tag;
59
60	u_int			target;
61	u_int			lun;
62
63	struct scsi_generic	cmd;
64	size_t			cmdlen;
65
66	size_t			datalen;
67	int			direction;
68#define VSCSI_DIR_NONE		0
69#define VSCSI_DIR_READ		1
70#define VSCSI_DIR_WRITE		2
71};
72.Ed
73.Pp
74.It Dv VSCSI_DATA_READ Fa "struct vscsi_ioc_data *"
75.It Dv VSCSI_DATA_WRITE Fa "struct vscsi_ioc_data *"
76Read or write data in response to a SCSI command identified by tag.
77.Bd -literal -offset indent
78struct vscsi_ioc_data {
79	int			tag;
80
81	void *			data;
82	size_t			datalen;
83};
84.Ed
85.Pp
86.It Dv VSCSI_T2I Fa "struct vscsi_ioc_t2i *"
87Signal completion of a SCSI command identified by tag.
88.Bd -literal -offset indent
89struct vscsi_ioc_t2i {
90	int			tag;
91
92	int			status;
93#define VSCSI_STAT_DONE		0
94#define VSCSI_STAT_SENSE	1
95#define VSCSI_STAT_RESET	2
96#define VSCSI_STAT_ERR		3
97	struct scsi_sense_data	sense;
98};
99.Ed
100.Pp
101.It Dv VSCSI_REQPROBE Fa "struct vscsi_ioc_devevent *"
102.It Dv VSCSI_REQDETACH Fa "struct vscsi_ioc_devevent *"
103Request a probe or a detach of the device at the addresses specified by the
104target and lun fields.
105.Bd -literal -offset indent
106struct vscsi_ioc_devevent {
107	u_int			target;
108	u_int			lun;
109};
110.Ed
111.El
112.Sh FILES
113.Bl -tag -width /dev/vscsi0
114.It /dev/vscsi0
115.El
116.Sh SEE ALSO
117.Xr ioctl 2 ,
118.Xr intro 4 ,
119.Xr scsi 4
120.Sh HISTORY
121The
122.Nm
123driver first appeared in
124.Ox 4.5 .
125.Sh AUTHORS
126.An David Gwynne Aq Mt dlg@openbsd.org .
127