1 sysfs interface 1 sysfs interface
2 --------------- 2 ---------------
3 The pktcdvd module (packet writing driver) cre 3 The pktcdvd module (packet writing driver) creates the following files in the
4 sysfs: (<devid> is in the format major:minor) 4 sysfs: (<devid> is in the format major:minor)
5 5
6 What: /sys/class/pktcdvd/add 6 What: /sys/class/pktcdvd/add
7 What: /sys/class/pktcdvd/remove 7 What: /sys/class/pktcdvd/remove
8 What: /sys/class/pktcdvd/device_map 8 What: /sys/class/pktcdvd/device_map
9 Date: Oct. 2006 9 Date: Oct. 2006
10 KernelVersion: 2.6.20 10 KernelVersion: 2.6.20
11 Contact: Thomas Maier <balagi@justmail.d 11 Contact: Thomas Maier <balagi@justmail.de>
12 Description: 12 Description:
13 13
14 ========== ============== 14 ========== ==============================================
15 add (WO) Write a b 15 add (WO) Write a block device id (major:minor) to
16 create a new p 16 create a new pktcdvd device and map it to the
17 block device. 17 block device.
18 18
19 remove (WO) Write the 19 remove (WO) Write the pktcdvd device id (major:minor)
20 to remove the 20 to remove the pktcdvd device.
21 21
22 device_map (RO) Shows the 22 device_map (RO) Shows the device mapping in format:
23 pktcdvd[0-7] < 23 pktcdvd[0-7] <pktdevid> <blkdevid>
24 ========== ============== 24 ========== ==============================================
25 25
26 26
27 What: /sys/class/pktcdvd/pktcdvd[0-7 27 What: /sys/class/pktcdvd/pktcdvd[0-7]/dev
28 What: /sys/class/pktcdvd/pktcdvd[0-7 28 What: /sys/class/pktcdvd/pktcdvd[0-7]/uevent
29 Date: Oct. 2006 29 Date: Oct. 2006
30 KernelVersion: 2.6.20 30 KernelVersion: 2.6.20
31 Contact: Thomas Maier <balagi@justmail.d 31 Contact: Thomas Maier <balagi@justmail.de>
32 Description: 32 Description:
33 dev: (RO) Device id 33 dev: (RO) Device id
34 34
35 uevent: (WO) To send a uevent 35 uevent: (WO) To send a uevent
36 36
37 37
38 What: /sys/class/pktcdvd/pktcdvd[0-7 38 What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/packets_started
39 What: /sys/class/pktcdvd/pktcdvd[0-7 39 What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/packets_finished
40 What: /sys/class/pktcdvd/pktcdvd[0-7 40 What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/kb_written
41 What: /sys/class/pktcdvd/pktcdvd[0-7 41 What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/kb_read
42 What: /sys/class/pktcdvd/pktcdvd[0-7 42 What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/kb_read_gather
43 What: /sys/class/pktcdvd/pktcdvd[0-7 43 What: /sys/class/pktcdvd/pktcdvd[0-7]/stat/reset
44 Date: Oct. 2006 44 Date: Oct. 2006
45 KernelVersion: 2.6.20 45 KernelVersion: 2.6.20
46 Contact: Thomas Maier <balagi@justmail.d 46 Contact: Thomas Maier <balagi@justmail.de>
47 Description: 47 Description:
48 packets_started: (RO) N 48 packets_started: (RO) Number of started packets.
49 49
50 packets_finished: (RO) N 50 packets_finished: (RO) Number of finished packets.
51 51
52 kb_written: (RO) k 52 kb_written: (RO) kBytes written.
53 53
54 kb_read: (RO) k 54 kb_read: (RO) kBytes read.
55 55
56 kb_read_gather: (RO) k 56 kb_read_gather: (RO) kBytes read to fill write packets.
57 57
58 reset: (WO) W 58 reset: (WO) Write any value to it to reset
59 pktcdv 59 pktcdvd device statistic values, like
60 bytes 60 bytes read/written.
61 61
62 62
63 What: /sys/class/pktcdvd/pktcdvd[0-7 63 What: /sys/class/pktcdvd/pktcdvd[0-7]/write_queue/size
64 What: /sys/class/pktcdvd/pktcdvd[0-7 64 What: /sys/class/pktcdvd/pktcdvd[0-7]/write_queue/congestion_off
65 What: /sys/class/pktcdvd/pktcdvd[0-7 65 What: /sys/class/pktcdvd/pktcdvd[0-7]/write_queue/congestion_on
66 Date: Oct. 2006 66 Date: Oct. 2006
67 KernelVersion: 2.6.20 67 KernelVersion: 2.6.20
68 Contact: Thomas Maier <balagi@justmail.d 68 Contact: Thomas Maier <balagi@justmail.de>
69 Description: 69 Description:
70 ============== ============== 70 ============== ================================================
71 size (RO) Contains 71 size (RO) Contains the size of the bio write queue.
72 72
73 congestion_off (RW) If bio wr 73 congestion_off (RW) If bio write queue size is below this mark,
74 accept new bio 74 accept new bio requests from the block layer.
75 75
76 congestion_on (RW) If bio wr 76 congestion_on (RW) If bio write queue size is higher as this
77 mark, do no lo 77 mark, do no longer accept bio write requests
78 from the block 78 from the block layer and wait till the pktcdvd
79 device has pro 79 device has processed enough bio's so that bio
80 write queue si 80 write queue size is below congestion off mark.
81 A value of <= 81 A value of <= 0 disables congestion control.
82 ============== ============== 82 ============== ================================================
83 83
84 84
85 Example: 85 Example:
86 -------- 86 --------
87 To use the pktcdvd sysfs interface directly, y 87 To use the pktcdvd sysfs interface directly, you can do::
88 88
89 # create a new pktcdvd device mapped to /d 89 # create a new pktcdvd device mapped to /dev/hdc
90 echo "22:0" >/sys/class/pktcdvd/add 90 echo "22:0" >/sys/class/pktcdvd/add
91 cat /sys/class/pktcdvd/device_map 91 cat /sys/class/pktcdvd/device_map
92 # assuming device pktcdvd0 was created, lo 92 # assuming device pktcdvd0 was created, look at stat's
93 cat /sys/class/pktcdvd/pktcdvd0/stat/kb_wr 93 cat /sys/class/pktcdvd/pktcdvd0/stat/kb_written
94 # print the device id of the mapped block 94 # print the device id of the mapped block device
95 fgrep pktcdvd0 /sys/class/pktcdvd/device_m 95 fgrep pktcdvd0 /sys/class/pktcdvd/device_map
96 # remove device, using pktcdvd0 device id 96 # remove device, using pktcdvd0 device id 253:0
97 echo "253:0" >/sys/class/pktcdvd/remove 97 echo "253:0" >/sys/class/pktcdvd/remove
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.