Signed-off-by: Dmitry Fleytman <dmi...@daynix.com>
Signed-off-by: Yan Vugenfirer <y...@daynix.com>
---
include/net/checksum.h | 8 ++++++++
net/checksum.c | 28 ++++++++++++++++++++++++++++
2 files changed, 36 insertions(+)
diff --git a/include/net/checksum.h b/include/net/checksum.h
index 171924c..289c16c 100644
--- a/include/net/checksum.h
+++ b/include/net/checksum.h
@@ -19,6 +19,7 @@
#define QEMU_NET_CHECKSUM_H
#include <stdint.h>
+#include "qemu-common.h"
uint32_t net_checksum_add_cont(int len, uint8_t *buf, int seq);
uint16_t net_checksum_finish(uint32_t sum);
@@ -38,4 +39,11 @@ net_raw_checksum(uint8_t *data, int length)
return net_checksum_finish(net_checksum_add(length, data));
}
+/**
+ * Checksum calculation for scatter-gather vector
+ */
+uint32_t net_checksum_add_iov(const struct iovec *iov,
+ const unsigned int iov_cnt,
+ uint32_t iov_off, uint32_t size);
+
#endif /* QEMU_NET_CHECKSUM_H */
diff --git a/net/checksum.c b/net/checksum.c
index 4fa5563..9c813ff 100644
--- a/net/checksum.c
+++ b/net/checksum.c
@@ -84,3 +84,31 @@ void net_checksum_calculate(uint8_t *data, int length)
data[14+hlen+csum_offset] = csum >> 8;
data[14+hlen+csum_offset+1] = csum & 0xff;
}
+
+uint32_t
+net_checksum_add_iov(const struct iovec *iov, const unsigned int iov_cnt,
+ uint32_t iov_off, uint32_t size)
+{
+ size_t iovec_off, buf_off;
+ unsigned int i;
+ uint32_t res = 0;
+ uint32_t seq = 0;
+
+ iovec_off = 0;
+ buf_off = 0;
+ for (i = 0; i < iov_cnt && size; i++) {
+ if (iov_off < (iovec_off + iov[i].iov_len)) {
+ size_t len = MIN((iovec_off + iov[i].iov_len) - iov_off , size);
+ void *chunk_buf = iov[i].iov_base + (iov_off - iovec_off);
+
+ res += net_checksum_add_cont(len, chunk_buf, seq);
+ seq += len;
+
+ buf_off += len;
+ iov_off += len;
+ size -= len;
+ }
+ iovec_off += iov[i].iov_len;
+ }
+ return res;
+}
--
1.7.11.7
