Re: [Qemu-devel] [PATCH] block: Change bdrv_commit to handle multiple sectors at once

[Kevin Wolf]

Am 16.07.2010 20:16, schrieb Christoph Hellwig:
> On Fri, Jul 16, 2010 at 06:17:36PM +0200, Kevin Wolf wrote:
>> +    buf = qemu_malloc(2048 * BDRV_SECTOR_SIZE);
> 
> Please add a COMMIT_BUF_SIZE #define instead of the hardcoded 2048 in
> various places.
> 
>>      for (i = 0; i < total_sectors;) {
>> +        if (drv->bdrv_is_allocated(bs, i, 2048, &n)) {
>>  
>> +            if (bdrv_read(bs, i, buf, n) != 0) {
>> +                ret = -EIO;
>> +                goto ro_cleanup;
>> +            }
>> +
>> +            if (bdrv_write(bs->backing_hd, i, buf, n) != 0) {
>> +                ret = -EIO;
>> +                goto ro_cleanup;
>> +            }
>>          }
>> +        i += n;
> 
> Maybe it's just me, but I'd prefer n getting a more descriptive name
> (e.g. sector) and moving the increment of it into the for loop, e.g.
> 
>       for (sector = 0; sector < total_sectors; sector += n) {
>               if (!drv->bdrv_is_allocated(bs, i, 2048, &n))
>                       continue;
>               ...
>       }

So you mean i should be renamed, not n, right? I'll change these points
in v2.

Kevin