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Date: Wed, 27 Sep 2017 12:52:50 +0200
From: David Sterba <dsterba@suse.cz>
To: Josef Bacik <josef@toxicpanda.com>
Cc: linux-btrfs@vger.kernel.org, kernel-team@fb.com
Subject: Re: [PATCH] btrfs: fix send ioctl on 32bit with 64bit kernel
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On Tue, Sep 26, 2017 at 04:40:09PM -0400, Josef Bacik wrote:
> We pass in a pointer in our send arg struct, this means the struct size doesn't
> match with 32bit user space and 64bit kernel space.  Fix this by adding a compat
> mode and doing the appropriate conversion.

How does this differ from the existing workaround that adds the 32bit
structure (btrfs_ioctl_timespec_32 and
btrfs_ioctl_received_subvol_args_32 at the top of ioctl.c) and the
btrfs_compat_ioctl() (at the end of ioctl.c)?