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Date: Tue, 03 Apr 2012 19:53:23 +0800
From: Zhi Hui Li <zhihuili@linux.vnet.ibm.com>
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Subject: Re: [Qemu-devel] [PATCH v3] Replace bdrv_* to bdrv_aio_* functions
 in DMA mode in fdc.c.
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: zhihuili@cn.ibm.com, QEMU-devel <qemu-devel@nongnu.org>


I think what you say up is right, I will correct them, thank you very much!

>> +        bdrv_aio_readv(cur_drv->bs, fd_sector(cur_drv),
>> +&fdctrl->qiov, fdc_sector_num, fdctrl_read_DMA_cb, opaque_cb);
>> +        return dma_len;
>
> Should be return 0 since we haven't completed I/O yet.
>
> Stefan
>
>

I think the return value is not used not, so no matter what is returned 
it not necessary.

if set the dma_len = 0, when call void DMA_set_return(int nret)
function will return the real value;

:)