summaryrefslogtreecommitdiffstats
path: root/kernel/Documentation/ABI/testing/sysfs-class-pktcdvd
diff options
context:
space:
mode:
authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/ABI/testing/sysfs-class-pktcdvd
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/Documentation/ABI/testing/sysfs-class-pktcdvd')
-rw-r--r--kernel/Documentation/ABI/testing/sysfs-class-pktcdvd72
1 files changed, 72 insertions, 0 deletions
diff --git a/kernel/Documentation/ABI/testing/sysfs-class-pktcdvd b/kernel/Documentation/ABI/testing/sysfs-class-pktcdvd
new file mode 100644
index 000000000..b1c3f0263
--- /dev/null
+++ b/kernel/Documentation/ABI/testing/sysfs-class-pktcdvd
@@ -0,0 +1,72 @@
+What: /sys/class/pktcdvd/
+Date: Oct. 2006
+KernelVersion: 2.6.20
+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