2018-02-13 16:18:16 +08:00
|
|
|
What: /sys/block/*/device/sw_activity
|
|
|
|
|
Date: Jun, 2008
|
|
|
|
|
KernelVersion: v2.6.27
|
|
|
|
|
Contact: linux-ide@vger.kernel.org
|
|
|
|
|
Description:
|
|
|
|
|
(RW) Used by drivers which support software controlled activity
|
|
|
|
|
LEDs.
|
|
|
|
|
|
|
|
|
|
It has the following valid values:
|
|
|
|
|
|
|
|
|
|
0 OFF - the LED is not activated on activity
|
|
|
|
|
1 BLINK_ON - the LED blinks on every 10ms when activity is
|
|
|
|
|
detected.
|
|
|
|
|
2 BLINK_OFF - the LED is on when idle, and blinks off
|
|
|
|
|
every 10ms when activity is detected.
|
|
|
|
|
|
|
|
|
|
Note that the user must turn sw_activity OFF it they wish to
|
|
|
|
|
control the activity LED via the em_message file.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
What: /sys/block/*/device/unload_heads
|
|
|
|
|
Date: Sep, 2008
|
|
|
|
|
KernelVersion: v2.6.28
|
|
|
|
|
Contact: linux-ide@vger.kernel.org
|
|
|
|
|
Description:
|
|
|
|
|
(RW) Hard disk shock protection
|
|
|
|
|
|
|
|
|
|
Writing an integer value to this file will take the heads of the
|
|
|
|
|
respective drive off the platter and block all I/O operations
|
|
|
|
|
for the specified number of milliseconds.
|
|
|
|
|
|
|
|
|
|
- If the device does not support the unload heads feature,
|
|
|
|
|
access is denied with -EOPNOTSUPP.
|
|
|
|
|
- The maximal value accepted for a timeout is 30000
|
|
|
|
|
milliseconds.
|
|
|
|
|
- A previously set timeout can be cancelled and disk can resume
|
|
|
|
|
normal operation immediately by specifying a timeout of 0.
|
|
|
|
|
- Some hard drives only comply with an earlier version of the
|
|
|
|
|
ATA standard, but support the unload feature nonetheless.
|
|
|
|
|
There is no safe way Linux can detect these devices, so this
|
|
|
|
|
is not enabled by default. If it is known that your device
|
|
|
|
|
does support the unload feature, then you can tell the kernel
|
|
|
|
|
to enable it by writing -1. It can be disabled again by
|
|
|
|
|
writing -2.
|
|
|
|
|
- Values below -2 are rejected with -EINVAL
|
|
|
|
|
|
|
|
|
|
For more information, see
|
2019-06-14 02:07:43 +08:00
|
|
|
Documentation/admin-guide/laptops/disk-shock-protection.rst
|
2018-02-13 16:18:16 +08:00
|
|
|
|
|
|
|
|
|
|
|
|
|
What: /sys/block/*/device/ncq_prio_enable
|
|
|
|
|
Date: Oct, 2016
|
|
|
|
|
KernelVersion: v4.10
|
|
|
|
|
Contact: linux-ide@vger.kernel.org
|
|
|
|
|
Description:
|
|
|
|
|
(RW) Write to the file to turn on or off the SATA ncq (native
|
|
|
|
|
command queueing) support. By default this feature is turned
|
|
|
|
|
off.
|
