Re: [Qemu-devel] [PATCH v2 05/14] exec.c: Convert subpage memory ops to _with_attrs

["Alex Bennée" <alex.bennee@linaro.org>]

Peter Maydell <peter.maydell@linaro.org> writes:

> On 17 April 2015 at 17:15, Alex Bennée <alex.bennee@linaro.org> wrote:
>>
>> Peter Maydell <peter.maydell@linaro.org> writes:
>>
>>> Convert the subpage memory ops to _with_attrs; this will allow
>>> us to pass the attributes through to the underlying access
>>> functions. (Nothing uses the attributes yet.)
>>>
>>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>>> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
>>> Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
>>> ---
>>>  exec.c | 33 +++++++++++++++++++++------------
>>>  1 file changed, 21 insertions(+), 12 deletions(-)
>>>
>>> diff --git a/exec.c b/exec.c
>>> index 34dafd2..bba6f26 100644
>>> --- a/exec.c
>>> +++ b/exec.c
>>> @@ -1941,8 +1941,8 @@ static const MemoryRegionOps watch_mem_ops = {
>>>      .endianness = DEVICE_NATIVE_ENDIAN,
>>>  };
>>>
>>> -static uint64_t subpage_read(void *opaque, hwaddr addr,
>>> -                             unsigned len)
>>> +static MemTxResult subpage_read(void *opaque, hwaddr addr, uint64_t *data,
>>> +                                unsigned len, MemTxAttrs attrs)
>>>  {
>>>      subpage_t *subpage = opaque;
>>>      uint8_t buf[8];
>>> @@ -1951,23 +1951,29 @@ static uint64_t subpage_read(void *opaque, hwaddr addr,
>>>      printf("%s: subpage %p len %u addr " TARGET_FMT_plx "\n", __func__,
>>>             subpage, len, addr);
>>>  #endif
>>> -    address_space_read(subpage->as, addr + subpage->base, buf, len);
>>> +    if (address_space_read(subpage->as, addr + subpage->base, buf, len)) {
>>> +        return MEMTX_DECODE_ERROR;
>>> +    }
>>
>> Doesn't this mean we loose potential other error bits that are returned
>> by address_space_read()? Would MEMTX_ERROR ever potentially be returned?
>
> At this point in the series address_space_read() returns a bool.
> In the next patch we change the return type of address_space_read()
> and this code is also changed to match (ie it returns the error
> value).

Ah yes, the jumping between patch and final tree confused me.

Have a:

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

>
> -- PMM

-- 
Alex Bennée