Re: [libvirt] [PATCH 1/6] Add virDomainGetBlockInfo API to query disk sizing

On Wed, Apr 28, 2010 at 01:54:45PM +0100, Daniel P. Berrange wrote: > Some applications need to be able to query a guest's disk info, > even for paths not managed by the storage pool APIs. This adds > a very simple API to get this information, modelled on the > virStorageVolGetInfo API, but with an extra field 'physical'. > Normally 'physical' and 'allocation' will be identical, but > in the case of a qcow2-like file stored inside a block device > 'physical' will give the block device size, while 'allocation' > will give the qcow2 image size [....] > + > +/** virDomainBlockInfo: > + * > + * This struct provides information about the size of a block device backing store > + * > + * Examples: > + * > + * - Fully allocated raw file in filesystem: > + * * capacity, allocation, physical: All the same > + * > + * - Sparse raw file in filesystem: > + * * capacity: logical size of the file > + * * allocation, physical: number of blocks allocated to file > + * > + * - qcow2 file in filesystem > + * * capacity: logical size from qcow2 header > + * * allocation, physical: logical size of the file / highest qcow extent (identical) > + * > + * - qcow2 file in a block device > + * * capacity: logical size from qcow2 header > + * * allocation: highest qcow extent written > + * * physical: size of the block device container > + */ Argh, forgot that in my previous review, we need to explicitely tell the size units, I expect bytes but we're unsing kB in some places so... > +typedef struct _virDomainBlockInfo virDomainBlockInfo; > +typedef virDomainBlockInfo *virDomainBlockInfoPtr; > +struct _virDomainBlockInfo { > + unsigned long long capacity; /* logical size of the block device backing image */ > + unsigned long long allocation; /* allocated extent of the block device backing image */ > + unsigned long long physical; /* physical size of the container of the backing image */ > +}; s/size/size in bytes/g