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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Tong Zhang' <ztong0001@gmail.com>, Anders Larsen <al@alarsen.net>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH v3] qnx4: qnx4_block_map error handling
Thread-Topic: [PATCH v3] qnx4: qnx4_block_map error handling
Thread-Index: AQHWsW4xl10PEzYX6kyh1cQHa4gGXqm2Oy4Q
Date:   Tue, 3 Nov 2020 10:54:02 +0000
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 <20201102231420.1833852-1-ztong0001@gmail.com>
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From: Tong Zhang
> Sent: 02 November 2020 23:14
> 
> qnx4_block_map() may return -EIO on funny qnx4 fs image, in this case do
> not interpret -EIO as a correct block number

That commit message is now wrong.

Also 'blknum' is only 'unsigned long' so ~0ull is wrong.
It can be worth injecting an error and checking the error
propagation works.

What is the actual maximum file size?
Is there actually an 'out of range' blknum value
that can be used to signify an error without
changing the return value to 'long long'.

	David

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