73 lines
2.7 KiB
Text
73 lines
2.7 KiB
Text
|
What: /sys/class/pktcdvd/
|
||
|
|
Date: Oct. 2006
|
||
|
|
KernelVersion: 2.6.19
|
||
|
|
Contact: Thomas Maier <balagi@justmail.de>
|
||
|
|
Description:
|
||
|
|
|
||
|
|
sysfs interface
|
||
|
|
---------------
|
||
|
|
|
||
|
|
The pktcdvd module (packet writing driver) creates
|
||
|
|
these files in the sysfs:
|
||
|
|
(<devid> is in format major:minor )
|
||
|
|
|
||
|
|
/sys/class/pktcdvd/
|
||
|
|
add (0200) Write a block device id (major:minor)
|
||
|
|
to create a new pktcdvd device and map
|
||
|
|
it to the block device.
|
||
|
|
|
||
|
|
remove (0200) Write the pktcdvd device id (major:minor)
|
||
|
|
to it to remove the pktcdvd device.
|
||
|
|
|
||
|
|
device_map (0444) Shows the device mapping in format:
|
||
|
|
pktcdvd[0-7] <pktdevid> <blkdevid>
|
||
|
|
|
||
|
|
/sys/class/pktcdvd/pktcdvd[0-7]/
|
||
|
|
dev (0444) Device id
|
||
|
|
uevent (0200) To send an uevent.
|
||
|
|
|
||
|
|
/sys/class/pktcdvd/pktcdvd[0-7]/stat/
|
||
|
|
packets_started (0444) Number of started packets.
|
||
|
|
packets_finished (0444) Number of finished packets.
|
||
|
|
|
||
|
|
kb_written (0444) kBytes written.
|
||
|
|
kb_read (0444) kBytes read.
|
||
|
|
kb_read_gather (0444) kBytes read to fill write packets.
|
||
|
|
|
||
|
|
reset (0200) Write any value to it to reset
|
||
|
|
pktcdvd device statistic values, like
|
||
|
|
bytes read/written.
|
||
|
|
|
||
|
|
/sys/class/pktcdvd/pktcdvd[0-7]/write_queue/
|
||
|
|
size (0444) Contains the size of the bio write
|
||
|
|
queue.
|
||
|
|
|
||
|
|
congestion_off (0644) If bio write queue size is below
|
||
|
|
this mark, accept new bio requests
|
||
|
|
from the block layer.
|
||
|
|
|
||
|
|
congestion_on (0644) If bio write queue size is higher
|
||
|
|
as this mark, do no longer accept
|
||
|
|
bio write requests from the block
|
||
|
|
layer and wait till the pktcdvd
|
||
|
|
device has processed enough bio's
|
||
|
|
so that bio write queue size is
|
||
|
|
below congestion off mark.
|
||
|
|
A value of <= 0 disables congestion
|
||
|
|
control.
|
||
|
|
|
||
|
|
|
||
|
|
Example:
|
||
|
|
--------
|
||
|
|
To use the pktcdvd sysfs interface directly, you can do:
|
||
|
|
|
||
|
|
# create a new pktcdvd device mapped to /dev/hdc
|
||
|
|
echo "22:0" >/sys/class/pktcdvd/add
|
||
|
|
cat /sys/class/pktcdvd/device_map
|
||
|
|
# assuming device pktcdvd0 was created, look at stat's
|
||
|
|
cat /sys/class/pktcdvd/pktcdvd0/stat/kb_written
|
||
|
|
# print the device id of the mapped block device
|
||
|
|
fgrep pktcdvd0 /sys/class/pktcdvd/device_map
|
||
|
|
# remove device, using pktcdvd0 device id 253:0
|
||
|
|
echo "253:0" >/sys/class/pktcdvd/remove
|