On Fri, Feb 17, 2017 at 03:42:52PM -0600, Eric Blake wrote: > On 02/17/2017 03:37 PM, Jeff Cody wrote: > > On Fri, Feb 17, 2017 at 05:39:01PM +0100, Peter Lieven wrote: > >> if the passed qiov contains exactly one iov we can > >> pass the buffer directly. > >> > >> Signed-off-by: Peter Lieven <p...@kamp.de> > >> --- > >> block/nfs.c | 23 ++++++++++++++++------- > >> 1 file changed, 16 insertions(+), 7 deletions(-) > >> > >> diff --git a/block/nfs.c b/block/nfs.c > >> index ab5dcc2..bb4b75f 100644 > >> --- a/block/nfs.c > >> +++ b/block/nfs.c > >> @@ -295,20 +295,27 @@ static int coroutine_fn > >> nfs_co_pwritev(BlockDriverState *bs, uint64_t offset, > >> NFSClient *client = bs->opaque; > >> NFSRPC task; > >> char *buf = NULL; > >> + bool my_buffer = false; > > > > g_free() is a nop if buf is NULL, so there is no need for the my_buffer > > variable & check. > > Umm, yes there is: > > >> + if (iov->niov != 1) { > >> + buf = g_try_malloc(bytes); > >> + if (bytes && buf == NULL) { > >> + return -ENOMEM; > >> + } > >> + qemu_iovec_to_buf(iov, 0, buf, bytes); > >> + my_buffer = true; > >> + } else { > >> + buf = iov->iov[0].iov_base; > > If we took the else branch, then we definitely do not want to be calling > g_free(buf).
Doh! > > >> } > >> > >> - qemu_iovec_to_buf(iov, 0, buf, bytes); > >> - > >> if (nfs_pwrite_async(client->context, client->fh, > >> offset, bytes, buf, > >> nfs_co_generic_cb, &task) != 0) { > >> - g_free(buf); > >> + if (my_buffer) { > >> + g_free(buf); > >> + } > > It looks correct as-is to me. Indeed. Reviewed-by: Jeff Cody <jc...@redhat.com>