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From: Frederic Gobry <frederic.gobry@smartdata.ch>
To: linux-mtd@lists.infradead.org
Subject: mmap question
Date: Tue, 4 Jun 2002 15:22:54 +0200	[thread overview]
Message-ID: <20020604132254.GA4911@rhin.smartdata.ch> (raw)

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Hi,

I need to port an in-memory database so that it can use mtd
devices. The program currently uses mmap in order to access a file as
permanent storage. I discovered that using this capability is not
possible on jffs2, as mmap does not accept MAP_SHARED.

In my framework, write operations are performed by explicit calls, but
the data must be readable as if it were in a direct-access
memory. Would it be possible to do that on jffs2 (for instance,
open/write/close sessions to modify the data, but with immediate
update on the mmapped version of the file)

Alternatively, would it possible to use a raw MTD device to provide
the equivalent service ? I don't need filesystem semantic, as the
program already considers the data as a sequence of pages on a
flash-like device.

Thanks for any suggestion,

Frédéric

-- 
Frédéric Gobry    SMARTDATA    	  
      ---         http://www.smartdata.ch
Software Engineer Lausanne - Switzerland
                  +41 21 693 84 98

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             reply	other threads:[~2002-06-04 13:22 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-06-04 13:22 Frederic Gobry [this message]
2002-07-01 13:14 ` mmap question Frederic Gobry
2002-07-11 16:19   ` Frederic Gobry
2002-07-11 19:15     ` Jörn Engel
2002-07-12  7:57       ` Frederic Gobry
2002-07-12 15:08         ` Jörn Engel
2002-07-15  7:41           ` Frederic Gobry
2002-07-12 15:21         ` David Woodhouse

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