iov: Add iov_to_buf and iov_size helpers

iov_to_buf() puts the buffer contents in the iov in a linearized buffer.

iov_size() gets the length of the contents in the iov.

The iov_to_buf() function is the memcpy_to_iovec() function that was
used in virtio-ballon.c.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/hw/iov.h b/hw/iov.h
index 5e3e54123d..60a85470bd 100644
--- a/hw/iov.h
+++ b/hw/iov.h
@@ -14,3 +14,6 @@
 
 size_t iov_from_buf(struct iovec *iov, unsigned int iovcnt,
                     const void *buf, size_t size);
+size_t iov_to_buf(const struct iovec *iov, const unsigned int iovcnt,
+                  void *buf, size_t offset, size_t size);
+size_t iov_size(const struct iovec *iov, const unsigned int iovcnt);