diff options
| -rw-r--r-- | include/net/checksum.h | 12 | ||||
| -rw-r--r-- | net/checksum.c | 29 |
2 files changed, 41 insertions, 0 deletions
diff --git a/include/net/checksum.h b/include/net/checksum.h index 3e7b93d094..80203fb6e0 100644 --- a/include/net/checksum.h +++ b/include/net/checksum.h @@ -38,4 +38,16 @@ net_raw_checksum(uint8_t *data, int length) return net_checksum_finish(net_checksum_add(length, data)); } +/** + * net_checksum_add_iov: scatter-gather vector checksumming + * + * @iov: input scatter-gather array + * @iov_cnt: number of array elements + * @iov_off: starting iov offset for checksumming + * @size: length of data to be checksummed + */ +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 4fa5563e7c..14c08550e0 100644 --- a/net/checksum.c +++ b/net/checksum.c @@ -15,6 +15,7 @@ * along with this program; if not, see <http://www.gnu.org/licenses/>. */ +#include "qemu-common.h" #include "net/checksum.h" #define PROTO_TCP 6 @@ -84,3 +85,31 @@ 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; +} |