diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/admin-guide/device-mapper/delay.rst | 41 | ||||
-rw-r--r-- | Documentation/admin-guide/device-mapper/dm-crypt.rst | 4 | ||||
-rw-r--r-- | Documentation/admin-guide/device-mapper/vdo.rst | 7 |
3 files changed, 42 insertions, 10 deletions
diff --git a/Documentation/admin-guide/device-mapper/delay.rst b/Documentation/admin-guide/device-mapper/delay.rst index 917ba8c33359..4d667228e744 100644 --- a/Documentation/admin-guide/device-mapper/delay.rst +++ b/Documentation/admin-guide/device-mapper/delay.rst @@ -3,29 +3,52 @@ dm-delay ======== Device-Mapper's "delay" target delays reads and/or writes -and maps them to different devices. +and/or flushs and optionally maps them to different devices. -Parameters:: +Arguments:: <device> <offset> <delay> [<write_device> <write_offset> <write_delay> [<flush_device> <flush_offset> <flush_delay>]] -With separate write parameters, the first set is only used for reads. +Table line has to either have 3, 6 or 9 arguments: + +3: apply offset and delay to read, write and flush operations on device + +6: apply offset and delay to device, also apply write_offset and write_delay + to write and flush operations on optionally different write_device with + optionally different sector offset + +9: same as 6 arguments plus define flush_offset and flush_delay explicitely + on/with optionally different flush_device/flush_offset. + Offsets are specified in sectors. + Delays are specified in milliseconds. + Example scripts =============== :: - #!/bin/sh - # Create device delaying rw operation for 500ms - echo "0 `blockdev --getsz $1` delay $1 0 500" | dmsetup create delayed + # + # Create mapped device named "delayed" delaying read, write and flush operations for 500ms. + # + dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 0 500" :: + #!/bin/sh + # + # Create mapped device delaying write and flush operations for 400ms and + # splitting reads to device $1 but writes and flushs to different device $2 + # to different offsets of 2048 and 4096 sectors respectively. + # + dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 2048 0 $2 4096 400" +:: #!/bin/sh - # Create device delaying only write operation for 500ms and - # splitting reads and writes to different devices $1 $2 - echo "0 `blockdev --getsz $1` delay $1 0 0 $2 0 500" | dmsetup create delayed + # + # Create mapped device delaying reads for 50ms, writes for 100ms and flushs for 333ms + # onto the same backing device at offset 0 sectors. + # + dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 0 50 $2 0 100 $1 0 333" diff --git a/Documentation/admin-guide/device-mapper/dm-crypt.rst b/Documentation/admin-guide/device-mapper/dm-crypt.rst index 48a48bd09372..9f8139ff97d6 100644 --- a/Documentation/admin-guide/device-mapper/dm-crypt.rst +++ b/Documentation/admin-guide/device-mapper/dm-crypt.rst @@ -160,6 +160,10 @@ iv_large_sectors The <iv_offset> must be multiple of <sector_size> (in 512 bytes units) if this flag is specified. +integrity_key_size:<bytes> + Use an integrity key of <bytes> size instead of using an integrity key size + of the digest size of the used HMAC algorithm. + Module parameters:: max_read_size diff --git a/Documentation/admin-guide/device-mapper/vdo.rst b/Documentation/admin-guide/device-mapper/vdo.rst index c69ac186863a..a14e6d3e787c 100644 --- a/Documentation/admin-guide/device-mapper/vdo.rst +++ b/Documentation/admin-guide/device-mapper/vdo.rst @@ -251,7 +251,12 @@ The messages are: by the vdostats userspace program to interpret the output buffer. - dump: + config: + Outputs useful vdo configuration information. Mostly used + by users who want to recreate a similar VDO volume and + want to know the creation configuration used. + + dump: Dumps many internal structures to the system log. This is not always safe to run, so it should only be used to debug a hung vdo. Optional parameters to specify structures to |