2004-04-12 04:14:25

by Andy Lutomirski

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Subject: Re: [ACPI] Re: [PATCH] filling in ACPI method access via sysfs namespace

Alex Williamson wrote:

> On Sun, 2004-04-11 at 16:29, Matthew Wilcox wrote:
>
>>It seems unintuitive that you have to read the file for the method to
>>take effect. How about having the write function invoke the method and
>>(if there is a result) store it for later read-back via the read function?
>>It should be discarded on close, of course. A read() on a file with
>>no stored result should invoke the ACPI method (on the assumption this
>>is a parameter-less method) and return the result directly. Closing a
>>file should discard any result from the method.
>
>
> How's this? It behaves the way you described, but might be doing
> some questionable things with the buffer to get there. Is there a
> better place to store the return data than back into the buf passed to
> write() (aka file->private_data)? Without adding callbacks to
> open/close, I'm not sure how else we can dispose of the results on
> close. Thanks,

Is there any reason this shouldn't be an ioctl?

--Andy


2004-04-12 04:32:53

by Alex Williamson

[permalink] [raw]
Subject: Re: [ACPI] Re: [PATCH] filling in ACPI method access via sysfs namespace

On Sun, 2004-04-11 at 22:13, Andy Lutomirski wrote:

> Is there any reason this shouldn't be an ioctl?
>

See the thread John pointed me to on Friday:

http://sourceforge.net/mailarchive/message.php?msg_id=7455349

Matthew ended it with "sysfs does not support ioctls. case closed."
I'm rather fond of the methods living in the sysfs directory
structure...

Alex