Re: [PATCH 2/8] PM: suspend_block: Add driver to access suspend blockers from user-space

Arve Hjønnevåg
2010-05-26T10:47:29Z

2010/5/26 Peter Zijlstra <peterz@infradead.org>:
> On Fri, 2010-05-21 at 15:46 -0700, Arve Hjønnevåg wrote:
>> +To create a suspend blocker from user space, open the suspend_blocker
>> special
>> +device file:
>> +
>> +    fd = open("/dev/suspend_blocker", O_RDWR | O_CLOEXEC);
>> +
>> +then optionally call:
>> +
>> +    ioctl(fd, SUSPEND_BLOCKER_IOCTL_SET_NAME(strlen(name)), name);
>> +
>> +To activate the suspend blocker call:
>> +
>> +    ioctl(fd, SUSPEND_BLOCKER_IOCTL_BLOCK);
>> +
>> +To deactivate it call:
>> +
>> +    ioctl(fd, SUSPEND_BLOCKER_IOCTL_UNBLOCK);
>> +
>> +To destroy the suspend blocker, close the device:
>> +
>> +    close(fd);
>
> Urgh, please let the open() be BLOCK, the close() be UNBLOCK, and keep
> the SET_NAME thing if you really care.
>

That would be very inefficient.

--
Arve Hjønnevåg