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New sentence, new line. 

Use more/better formatting.
Fix a typo.
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wiz 2016-11-28 11:54:18 +00:00
parent 9185ad93b5
commit 238875cdff
1 changed files with 32 additions and 22 deletions
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54
share/man/man9/dksubr.9
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@ -1,4 +1,4 @@
.\" $NetBSD: dksubr.9,v 1.1 2016/11/28 11:00:24 mlelstv Exp $
.\" $NetBSD: dksubr.9,v 1.2 2016/11/28 11:54:18 wiz Exp $
.\"
.\" Copyright (c) 2016 The NetBSD Foundation, Inc.
.\" All rights reserved.
@ -87,7 +87,8 @@
.Fn dk_getdisklabel "struct dk_softc *" "dev_t"
.Sh DESCRIPTION
The disk driver subroutines provide common functionality for all disk drivers
to reduce the amount of replicated code. For many disk drivers, their
to reduce the amount of replicated code.
For many disk drivers, their
corresponding entry points can be made mostly stubs.
.Pp
The subroutines encapsulate data structures found in a driver's softc
@ -97,7 +98,7 @@ struct dk_softc {
device_t sc_dev;
struct disk sc_dkdev;
struct bufq_state sc_bufq;
krndsoruce_t sc_rnd_source;
krndsource_t sc_rnd_source;
...
}
.Ed
@ -129,7 +130,8 @@ callback to handle initialization steps.
.It Fn dk_close
Handles close steps for the
.Xr disk 9
framework. The driver may provide the
framework.
The driver may provide the
.Nm d_lastclose
callback to handle finalization steps.
.Nm dk_open
@ -142,7 +144,7 @@ these to the
.Nm d_discard
callback.
.It Fn dk_size
returns dump size information from the
Returns dump size information from the
.Xr disklabel 9
and opens and closes the driver when necessary.
.It Fn dk_dump
@ -154,17 +156,20 @@ callback in appropriate chunks determined by the
callback.
.It Fn dk_ioctl
Handles the ioctls
.Nm DIOCKLABEL
.Nm DIOCWLABEL
.Nm DIOCGDEFLABEL
.Nm DIOCGSTRATEGY
.Nm DIOCSSTRATEGY
.Dv DIOCKLABEL ,
.Dv DIOCWLABEL ,
.Dv DIOCGDEFLABEL ,
.Dv DIOCGSTRATEGY ,
and
.Dv DIOCSSTRATEGY
and passes other disk ioctls through the
.Xr disk 9
framework. Returns
framework.
Returns
.Nm ENOTTY
when an ioctl isn't implemented. This routine is run as a fallback to
handle commands, that are not specific to the driver.
when an ioctl isn't implemented.
This routine is run as a fallback to
handle commands that are not specific to the driver.
.It Fn dk_strategy
Validates parameters, computes raw block numbers, queues a buffer for I/O
and triggers queue processing by calling
@ -172,7 +177,8 @@ and triggers queue processing by calling
.It Fn dk_strategy_defer
Alternative to
.Nm dk_strategy
that only queues the buffer. Drivers that implement a separate I/O thread
that only queues the buffer.
Drivers that implement a separate I/O thread
can use
.Nm dk_strategy_defer
within their own strategy routine and signal the thread through a private
@ -185,12 +191,16 @@ The driver must then call
.Nm dk_start
to trigger queue processing.
.It Fn dk_start
If bp != NULL put it into the queue. Run the
If
.Ar bp != Dv NULL
put it into the queue.
Run the
.Nm d_diskstart
callback for every buffer until the queue is empty or the callback returns
.Nm EAGAIN .
In the latter case, the buffer is saved and issued on the
next queue run. This also calls
next queue run.
This also calls
.Nm disk_busy
accordingly to handle I/O metrics.
.It Fn dk_done
@ -201,8 +211,8 @@ logs errors, calls
to handle I/O metrics and collects entropy for the
.Xr cprng 9 .
.It Fn dk_drain
Aborts all queued I/O. This function must be called instead
of
Aborts all queued I/O.
This function must be called instead of
.Fn bufq_drain
to cooperate with
.Nm dk_start .
@ -250,8 +260,8 @@ Truncate I/O size to the driver limit.
Issue a single I/O requests, called by
.Nm dk_dump .
.It Fn d_lastclose
Private cleanup after last user is finished. Often used to
flush write caches.
Private cleanup after last user is finished.
Often used to flush write caches.
.It Fn d_discard
Issue a single I/O request to invalidate a disk region.
.It Fn d_firstopen
@ -282,6 +292,6 @@ The framework includes a
.Nm dk_lookup
helper function, that is used by the
.Xr cgd 4
driver to open a vnode for a block device. This looks too generic
driver to open a vnode for a block device.
This looks too generic
and should be put somewhere better (and be renamed).