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Date: Thu, 19 Aug 2004 21:16:13 +1000
From: Paul Mackerras <paulus@samba.org>
To: akpm@osdl.org, viro@parcelfarce.linux.theplanet.co.uk
Cc: Olof Johansson <olof@austin.ibm.com>, linux-kernel@vger.kernel.org
Subject: Alignment of bitmaps for ext2_set_bit et al.
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What can we assume about the alignment of the bitmap pointer passed to
the ext2_{set,clear}_bit_atomic functions?  Can we assume that they
will be aligned to an long boundary (8 bytes on 64-bit)?

Olof has made a patch that uses atomics for these on ppc64 rather than
locking and unlocking a lock, but it will only work correctly if the
bitmap is always 8-byte aligned.

Paul.