From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Sat, 26 Mar 2016 01:10:07 -0500
From: Eric Biggers <ebiggers3@gmail.com>
To: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux FS Dev Mailing List <linux-fsdevel@vger.kernel.org>,
	Linux F2FS Dev Mailing List
	<linux-f2fs-devel@lists.sourceforge.net>
Subject: Re: [GIT PULL] f2fs updates for v4.6
Message-ID: <20160326061007.GA24620@zzz>
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 <20160321184520.GA8199@jaegeuk.gateway>
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Why was the XTS tweak initialization changed in commit 0b81d0779072 ("fs crypto:
move per-file encryption from f2fs tree to fs/crypto")?

Old code:

       memcpy(xts_tweak, &index, sizeof(index));
       memset(&xts_tweak[sizeof(index)], 0,
                       F2FS_XTS_TWEAK_SIZE - sizeof(index));

New code:
       memcpy(xts_tweak, &inode->i_ino, sizeof(index));
       memset(&xts_tweak[sizeof(index)], 0,
                       FS_XTS_TWEAK_SIZE - sizeof(index));

Now the XTS tweak is the same for all pages of each inode.