On 05/25/2017 12:03 PM, Vladimir Sementsov-Ogievskiy wrote: > 25.05.2017 19:32, Eric Blake wrote: >> On 05/25/2017 10:26 AM, Vladimir Sementsov-Ogievskiy wrote: >>> Current comment is not clear enough: which sparseness is meant, coming >>> from sparse image format or from sparse file system? >>> >>> For example, if we have qcow2 above raw file on non-sparse file system, >>> this function will say nothing about unallocated (by qcow2 layer) >>> clusters. >>>
>>> + * Size of allocated in underlying file system area. Sparseness is >>> taken into >> Doesn't read well. Maybe: s/Size of allocated/Allocation size/ ? >> >>> + * account for sparse file systems. Return < 0 if error or unknown. >> I still don't get what we are trying to present. >> >> >> I think we still need to do a better job at writing a precise comment. >> > > bdrv_get_allocated_file_size is not related to qcow2, as qcow2 doesn't > support it. So, it is finally just raw_get_allocated_file_size, which > returns st.st_blocks * 512 after fstat(s->fd). > > It will correspond to qcow2 sparseness if qcow2 discarded corresponding > clusters in bs->file and if underlying fs is sparse. Okay, that helps. How about this wording: Allocation size of the underlying file system area. Sparseness is taken into account (holes do not contribute to this size). Return < 0 if error or unknown. -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org
signature.asc
Description: OpenPGP digital signature
