[U-Boot] [PATCH 2/2] ext2: Simplify partial sector access logic

Detlev Zundel dzu at denx.de
Wed Jun 29 15:04:29 CEST 2011


Hi Anton,

> Previously reading or writing zero full sectors (reading the end of
> one sector and the beginning of the next for example) was special
> cased and involved stack allocating a second sector buffer.  This
> change uses the same code path for this case as well as when there
> are a non-zero number of full sectors to access.  The result is
> easier to read and reduces the maximum stack used.

It's non-trivial to prove that your change is equivalent and
unfortunately I do not have enough time to do this.  If your tests work,
than this is certainly a good indication ;) The one thing I'd like to be
sure is that the previous code looks like it used the stack for whole
sectors but copied only parts of this to the provided address pointer.
Your new code looks like it always writes whole sectors to the provided
pointer.  Is this safe even if the caller allocated space without
overhead for whole sectors?

Cheers
  Detlev

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