Re: [PATCH 24/28] async_xor: use xor_gen

From: Dan Williams <djbw@kernel.org>
To: Christoph Hellwig <hch@lst.de>
Cc: Richard Henderson <richard.henderson@linaro.org>,
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Subject: Re: [PATCH 24/28] async_xor: use xor_gen
Date: Thu, 09 Apr 2026 20:19:47 -0700	[thread overview]
Message-ID: <69d86c53cfc4_2b31100e7@djbw-dev.notmuch> (raw)
In-Reply-To: <20260327061704.3707577-25-hch@lst.de>

Christoph Hellwig wrote:
> Replace use of the loop around xor_blocks with the easier to use xor_gen
> API.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  crypto/async_tx/async_xor.c | 34 ++++++++++------------------------
>  1 file changed, 10 insertions(+), 24 deletions(-)
[..]
> @@ -168,11 +156,10 @@ dma_xor_aligned_offsets(struct dma_device *device, unsigned int offset,
>   *
>   * honored flags: ASYNC_TX_ACK, ASYNC_TX_XOR_ZERO_DST, ASYNC_TX_XOR_DROP_DST
>   *
> - * xor_blocks always uses the dest as a source so the
> - * ASYNC_TX_XOR_ZERO_DST flag must be set to not include dest data in
> - * the calculation.  The assumption with dma engines is that they only
> - * use the destination buffer as a source when it is explicitly specified
> - * in the source list.
> + * xor_gen always uses the dest as a source so the ASYNC_TX_XOR_ZERO_DST flag
> + * must be set to not include dest data in the calculation.  The assumption with
> + * dma engines is that they only use the destination buffer as a source when it
> + * is explicitly specified in the source list.
>   *
>   * src_list note: if the dest is also a source it must be at index zero.
>   * The contents of this array will be overwritten if a scribble region
> @@ -259,11 +246,10 @@ EXPORT_SYMBOL_GPL(async_xor_offs);
>   *
>   * honored flags: ASYNC_TX_ACK, ASYNC_TX_XOR_ZERO_DST, ASYNC_TX_XOR_DROP_DST
>   *
> - * xor_blocks always uses the dest as a source so the
> - * ASYNC_TX_XOR_ZERO_DST flag must be set to not include dest data in
> - * the calculation.  The assumption with dma engines is that they only
> - * use the destination buffer as a source when it is explicitly specified
> - * in the source list.
> + * xor_gen always uses the dest as a source so the ASYNC_TX_XOR_ZERO_DST flag
> + * must be set to not include dest data in the calculation.  The assumption with
> + * dma engines is that they only use the destination buffer as a source when it
> + * is explicitly specified in the source list.

In retrospect, no need to duplicate this help, but as is:

Reviewed-by: Dan Williams <djbw@kernel.org>