Re: [Qemu-devel] [PATCHv3 3/9] allow qemu_iovec_from_buffer() to specify offset from which to start copying

[Kevin Wolf]

Am 12.03.2012 20:14, schrieb Michael Tokarev:
> Similar to
>  qemu_iovec_memset(QEMUIOVector *qiov, size_t offset,
>                    int c, size_t bytes);
> the new prototype is:
>  qemu_iovec_from_buf(QEMUIOVector *qiov, size_t offset,
>                      const void *buf, size_t bytes);
> 
> The processing starts at offset bytes within qiov.
> 
> This way, we may copy a bounce buffer directly to
> a middle of qiov.
> 
> This is exactly the same function as iov_from_buf() from
> iov.c, so use the existing implementation and rename it
> to qemu_iovec_from_buf() to be shorter and to match the
> utility function.
> 
> As with utility implementation, we now assert that the
> offset is inside actual iovec.  Nothing changed for
> current callers, because `offset' parameter is new.
> 
> While at it, stop using "bounce-qiov" in block/qcow2.c
> and copy decrypted data directly from cluster_data
> instead of recreating a temp qiov for doing that
> (Cc'ing kwolf for this change).

Looks good to me.

Kevin