consolidate qemu_iovec_memset{,_skip}() into single function and use existing iov_memset()

This patch combines two functions into one, and replaces
the implementation with already existing iov_memset() from
iov.c.

The new prototype of qemu_iovec_memset():
  size_t qemu_iovec_memset(qiov, size_t offset, int fillc, size_t bytes)
It is different from former qemu_iovec_memset_skip(), and
I want to make other functions to be consistent with it
too: first how much to skip, second what, and 3rd how many
of it.  It also returns actual number of bytes filled in,
which may be less than the requested `bytes' if qiov is
smaller than offset+bytes, in the same way iov_memset()
does.

While at it, use utility function iov_memset() from
iov.h in posix-aio-compat.c, where qiov was used.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

1 files changed, 3 insertions, 5 deletions

diff --git a/posix-aio-compat.c b/posix-aio-compat.c
index 68361f555a..96e4daf505 100644
--- a/posix-aio-compat.c
+++ b/posix-aio-compat.c
@@ -29,6 +29,7 @@
 #include "qemu-common.h"
 #include "trace.h"
 #include "block_int.h"
+#include "iov.h"
 
 #include "block/raw-posix-aio.h"
 
@@ -351,11 +352,8 @@ static void *aio_thread(void *unused)
             if (ret >= 0 && ret < aiocb->aio_nbytes && aiocb->common.bs->growable) {
                 /* A short read means that we have reached EOF. Pad the buffer
                  * with zeros for bytes after EOF. */
-                QEMUIOVector qiov;
-
-                qemu_iovec_init_external(&qiov, aiocb->aio_iov,
-                                         aiocb->aio_niov);
-                qemu_iovec_memset_skip(&qiov, 0, aiocb->aio_nbytes - ret, ret);
+                iov_memset(aiocb->aio_iov, aiocb->aio_niov, ret,
+                           0, aiocb->aio_nbytes - ret);
 
                 ret = aiocb->aio_nbytes;
             }