Re: [PATCH 2/2] scsi: Use new __dma_buffer to align sense buffer in scsi_cmnd

From: Roland Dreier
Date: Fri Dec 21 2007 - 11:58:04 EST


> It's also incomplete as a fix because I don't see what guarantees the
> buffer size will always exceed cache line size

There's a macro trick that adds a pad member after the buffer too, so
that it gets rounded up to the cacheline size:

> +#define __dma_aligned __attribute__((aligned(ARCH_MIN_DMA_ALIGNMENT)))
> +#define __dma_buffer __dma_buffer_line(__LINE__)
> +#define __dma_buffer_line(line) __dma_aligned;\
> + char __dma_pad_##line[0] __dma_aligned

So that part is OK at least.

- R.
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