Re: [Qemu-devel] [PATCH] Use DMADirection type for dma_bdrv_io

[Andreas Färber]

Am 22.02.2012 02:11, schrieb David Gibson:
> On Tue, Feb 21, 2012 at 10:09:01AM +0100, Kevin Wolf wrote:
>> Am 21.02.2012 09:35, schrieb Paolo Bonzini:
>>> On 02/20/2012 11:50 AM, Alexander Graf wrote:
>>>>>>     DMAAIOCB *dbs = qemu_aio_get(&dma_aio_pool, bs, cb, opaque);
>>>>>>
>>>>>> -    trace_dma_bdrv_io(dbs, bs, sector_num, to_dev);
>>>>>> +    trace_dma_bdrv_io(dbs, bs, sector_num, dir);
>>>> Was the trace wrong before or is it now? I don't see its definition 
>>>> changed anywhere.
>>>
>>> Not sure what you mean. :)
>>
>> trace-events:
>>
>> dma_bdrv_io(void *dbs, void *bs, int64_t sector_num, bool to_dev)
>> "dbs=%p bs=%p sector_num=%" PRId64 " to_dev=%d"
> 
> Ah, damnit.  Didn't find that file.  I'll resubmit with trace-events
> updated too.
> 
>> to_dev is declared bool here, and it should also be renamed to dir (the
>> unfortunate thing about DMADirection is that it swaps 0 and 1 compared
>> to bool to_dev... We need to check carefully that all occurrences have
>> been caught.)
> 
> Yeah.  And even more unfortunate that afaict there's no way to make
> gcc warn on enum<->bool conversions.  Still there are only about 4
> callers of dma_bdrv_io() - nearly everything uses the
> dma_bdrv_{read,write}() wrappers - so I'm confident I got them all.

Re all occurrences: megasas might be affected by such a change, too
(patch on the list).

Andreas

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