On 12/11/20 12:39 PM, Vladimir Sementsov-Ogievskiy wrote: > We are generally moving to int64_t for both offset and bytes parameters > on all io paths. > > Main motivation is realization of 64-bit write_zeroes operation for > fast zeroing large disk chunks, up to the whole disk. > > We chose signed type, to be consistent with off_t (which is signed) and > with possibility for signed return type (where negative value means > error). > > So, prepare bdrv_aligned_pwritev() now and convert the dependencies: > bdrv_co_write_req_prepare() and bdrv_co_write_req_finish() to signed > type bytes. > > Conversion of bdrv_co_write_req_prepare() and > bdrv_co_write_req_finish() is definitely safe, as all requests in > block/io must not overflow BDRV_MAX_LENGTH. Still add assertions. > > For bdrv_aligned_pwritev() 'bytes' type is widened, so callers are > safe. Let's check usage of the parameter inside the function. > > Passing to bdrv_co_write_req_prepare() and bdrv_co_write_req_finish() > is OK. > > Passing to qemu_iovec_* is OK after new assertion. All other callees > are already updated to int64_t. > > Checking alignment is not changed, offset + bytes and qiov_offset + > bytes calculations are safe (thanks to new assertions). > > max_transfer is kept to be int for now. It has a default of INT_MAX > here, and some drivers may rely on it. It's to be refactored later. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> > --- > block/io.c | 21 +++++++++++++-------- > 1 file changed, 13 insertions(+), 8 deletions(-) >
Reviewed-by: Eric Blake <ebl...@redhat.com> -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3226 Virtualization: qemu.org | libvirt.org
