[RFC, PATCH] XFS_TRANS_DEBUG fixes

[Christoph Hellwig]

On Fri, Dec 05, 2008 at 06:10:24PM +1100, Lachlan McIlroy wrote:
> Some of the things I had to do to get it to work (and could be done some other
> way) are:
> - all buffers that are logged need to be mapped into kernel space so the
>    debugging code can make a copy of the buffer data and compare it later.
>    The easiest way to do that is to make all buffers mapped in xfs_bug_get_flags()
>    when XFS_TRANS_DEBUG is set.

Need a comment similar to this next to the place that sets the flag.

> - Some bit setting functions (btst()/bset()/bfset()) appear to be missing so
>    I've coded up some trivial versions.  There maybe some linux kernel functions
>    that do the same thing.

Just use the Linu set_bit / clear_bit / test_bit / test_and_set_bit /
test_and_clear_bit helpers, or the __ prefixed versions if you don't
need atomicy.  Note that they want to have pointers to unsigned long
passed.