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 for linux-mtd@lists.infradead.org; Tue, 13 Mar 2012 12:39:49 +0000
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Subject: Re: MTD API locking and concurrency
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Robert Jarzmik <robert.jarzmik@free.fr>
Date: Tue, 13 Mar 2012 14:41:11 +0200
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On Tue, 2012-03-13 at 06:45 +0100, Robert Jarzmik wrote:
> Hi,
>=20
> I came across a concurrent usage of my MTD driver by UBIFS by doing
> an IOC_UBI_UPVOL. As my chip doesn't support multiple requests at a time,=
 I need
> to protect the access to chip registers.
>=20
> I wonder if mtd api function can be called in interrupt context.

No, this is not explicitely documented and you are welcome to send a
patch which adds a comment to mtd.h, but all the MTD API functions are
supposed to be called from sleeping context. IOW, the caller should keep
in mind that these functions may sleep.

--=20
Best Regards,
Artem Bityutskiy

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