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Diffstat (limited to 'Documentation/ABI/testing/sysfs-class-pktcdvd')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-pktcdvd | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-pktcdvd b/Documentation/ABI/testing/sysfs-class-pktcdvd new file mode 100644 index 000000000000..ba1ce626591d --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-pktcdvd @@ -0,0 +1,97 @@ +sysfs interface +--------------- +The pktcdvd module (packet writing driver) creates the following files in the +sysfs: (<devid> is in the format major:minor) + +What: /sys/class/pktcdvd/add +What: /sys/class/pktcdvd/remove +What: /sys/class/pktcdvd/device_map +Date: Oct. 2006 +KernelVersion: 2.6.20 +Contact: Thomas Maier <balagi@justmail.de> +Description: + + ========== ============================================== + add (WO) Write a block device id (major:minor) to + create a new pktcdvd device and map it to the + block device. + + remove (WO) Write the pktcdvd device id (major:minor) + to remove the pktcdvd device. + + device_map (RO) Shows the device mapping in format: + pktcdvd[0-7] <pktdevid> <blkdevid> + ========== ============================================== + + +What: /sys/class/pktcdvd/pktcdvd[0-7]/dev +What: /sys/class/pktcdvd/pktcdvd[0-7]/uevent +Date: Oct. 2006 +KernelVersion: 2.6.20 +Contact: Thomas Maier <balagi@justmail.de> +Description: + dev: (RO) Device id + + uevent: (WO) To send a uevent + + +What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/packets_started +What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/packets_finished +What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/kb_written +What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/kb_read +What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/kb_read_gather +What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/reset +Date: Oct. 2006 +KernelVersion: 2.6.20 +Contact: Thomas Maier <balagi@justmail.de> +Description: + packets_started: (RO) Number of started packets. + + packets_finished: (RO) Number of finished packets. + + kb_written: (RO) kBytes written. + + kb_read: (RO) kBytes read. + + kb_read_gather: (RO) kBytes read to fill write packets. + + reset: (WO) Write any value to it to reset + pktcdvd device statistic values, like + bytes read/written. + + +What: /sys/class/pktcdvd/pktcdvd[0-7]/write_queue/size +What: /sys/class/pktcdvd/pktcdvd[0-7]/write_queue/congestion_off +What: /sys/class/pktcdvd/pktcdvd[0-7]/write_queue/congestion_on +Date: Oct. 2006 +KernelVersion: 2.6.20 +Contact: Thomas Maier <balagi@justmail.de> +Description: + ============== ================================================ + size (RO) Contains the size of the bio write queue. + + congestion_off (RW) If bio write queue size is below this mark, + accept new bio requests from the block layer. + + congestion_on (RW) 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 |