Re: [Qemu-devel] [PATCH v3 13/14] block: Remove "growable" from BDS

[Max Reitz <mreitz@redhat.com>]

On 2015-02-02 at 14:46, Kevin Wolf wrote:
> Am 26.01.2015 um 16:00 hat Max Reitz geschrieben:
>> Now that request clamping is done in the BlockBackend, the "growable"
>> field can be removed from the BlockDriverState. All BDSs are now treated
>> as being "growable" (that is, they are allowed to grow; they are not
>> necessarily actually able to).
>>
>> Signed-off-by: Max Reitz <mreitz@redhat.com>
>> ---
>>   block.c                   | 24 +++++-------------------
>>   block/qcow2.c             |  6 ------
>>   block/raw-posix.c         |  2 +-
>>   block/raw-win32.c         |  2 +-
>>   block/sheepdog.c          |  2 +-
>>   include/block/block_int.h |  3 ---
>>   6 files changed, 8 insertions(+), 31 deletions(-)
>>
>> diff --git a/block.c b/block.c
>> index d45e4dd..356a857 100644
>> --- a/block.c
>> +++ b/block.c
>> @@ -970,7 +970,6 @@ static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
>>       bs->zero_beyond_eof = true;
>>       open_flags = bdrv_open_flags(bs, flags);
>>       bs->read_only = !(open_flags & BDRV_O_RDWR);
>> -    bs->growable = !!(flags & BDRV_O_PROTOCOL);
>>   
>>       if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) {
>>           error_setg(errp,
>> @@ -1885,7 +1884,6 @@ void bdrv_close(BlockDriverState *bs)
>>           bs->encrypted = 0;
>>           bs->valid_key = 0;
>>           bs->sg = 0;
>> -        bs->growable = 0;
>>           bs->zero_beyond_eof = false;
>>           QDECREF(bs->options);
>>           bs->options = NULL;
>> @@ -2645,25 +2643,13 @@ exit:
>>   static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
>>                                      size_t size)
>>   {
>> -    int64_t len;
>> -
>>       if (size > INT_MAX) {
>>           return -EIO;
>>       }
>>   
>> -    if (!bdrv_is_inserted(bs))
>> +    if (!bdrv_is_inserted(bs)) {
>>           return -ENOMEDIUM;
>> -
>> -    if (bs->growable)
>> -        return 0;
>> -
>> -    len = bdrv_getlength(bs);
>> -
>> -    if (offset < 0)
>> -        return -EIO;
> Wouldn't it be better to keep this one, even though bs->growable used to
> disable it?

Indeed, there shouldn't be any harm in keeping it.

Max