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envelope-from=zycai@linux.ibm.com; helo=mx0b-001b2d01.pphosted.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org The virtio-net device used a fixed header size that did not account for the num_buffers field used in VirtIO 1.0 or for the mergeable receive buffers feature. Use dynamic header sizing: 10 bytes for legacy mode and 12 bytes for VirtIO 1.0 or when VIRTIO_NET_F_MRG_RXBUF is enabled. This ensures correct packet handling across different VirtIO configurations. Signed-off-by: Zhuoying Cai --- pc-bios/s390-ccw/virtio-net.c | 30 ++++++++++++++++++++++++------ 1 file changed, 24 insertions(+), 6 deletions(-) diff --git a/pc-bios/s390-ccw/virtio-net.c b/pc-bios/s390-ccw/virtio-net.c index f58f7ffc55..afa728bc32 100644 --- a/pc-bios/s390-ccw/virtio-net.c +++ b/pc-bios/s390-ccw/virtio-net.c @@ -20,6 +20,7 @@ #include "s390-ccw.h" #include "virtio.h" #include "virtio-ccw.h" +#include "virtio-pci.h" #include "s390-time.h" #include "helper.h" @@ -28,6 +29,7 @@ #endif #define VIRTIO_NET_F_MAC_BIT (1 << 5) +#define VIRTIO_NET_F_MRG_RXBUF_BIT (1 << 15) #define VQ_RX 0 /* Receive queue */ #define VQ_TX 1 /* Transmit queue */ @@ -43,7 +45,18 @@ struct VirtioNetHdr { }; typedef struct VirtioNetHdr VirtioNetHdr; +struct VirtioNetHdrMrgRxbuf { + struct VirtioNetHdr hdr; + uint16_t num_buffers; /* Only with VIRTIO_NET_F_MRG_RXBUF or VIRTIO1 */ +}; +typedef struct VirtioNetHdrMrgRxbuf VirtioNetHdrMrgRxbuf; + +/* Header sizes for different modes */ +#define VIRTIO_NET_HDR_SIZE_LEGACY sizeof(VirtioNetHdr) +#define VIRTIO_NET_HDR_SIZE_V1 sizeof(VirtioNetHdrMrgRxbuf) + static uint16_t rx_last_idx; /* Last index in receive queue "used" ring */ +static int virtio_net_hdr_size; int virtio_net_init(void *mac_addr) { @@ -62,12 +75,17 @@ int virtio_net_init(void *mac_addr) return -1; } + virtio_net_hdr_size = ((vdev->guest_features[1] & VIRTIO_F_VERSION_1) || + (vdev->guest_features[0] & VIRTIO_NET_F_MRG_RXBUF_BIT)) + ? VIRTIO_NET_HDR_SIZE_V1 + : VIRTIO_NET_HDR_SIZE_LEGACY; + memcpy(mac_addr, vdev->config.net.mac, ETH_ALEN); for (i = 0; i < 64; i++) { - buf = malloc(ETH_MTU_SIZE + sizeof(VirtioNetHdr)); + buf = malloc(ETH_MTU_SIZE + virtio_net_hdr_size); IPL_assert(buf != NULL, "Can not allocate memory for receive buffers"); - vring_send_buf(rxvq, buf, ETH_MTU_SIZE + sizeof(VirtioNetHdr), + vring_send_buf(rxvq, buf, ETH_MTU_SIZE + virtio_net_hdr_size, VRING_DESC_F_WRITE); } vring_notify(rxvq); @@ -77,14 +95,14 @@ int virtio_net_init(void *mac_addr) int send(int fd, const void *buf, int len, int flags) { - VirtioNetHdr tx_hdr; + VirtioNetHdrMrgRxbuf tx_hdr; VDev *vdev = virtio_get_device(); VRing *txvq = &vdev->vrings[VQ_TX]; /* Set up header - we do not use anything special, so simply clear it */ memset(&tx_hdr, 0, sizeof(tx_hdr)); - vring_send_buf(txvq, &tx_hdr, sizeof(tx_hdr), VRING_DESC_F_NEXT); + vring_send_buf(txvq, &tx_hdr, virtio_net_hdr_size, VRING_DESC_F_NEXT); vring_send_buf(txvq, (void *)buf, len, VRING_HIDDEN_IS_CHAIN); while (!vr_poll(txvq)) { yield(); @@ -108,13 +126,13 @@ int recv(int fd, void *buf, int maxlen, int flags) return 0; } - len = rxvq->used->ring[rx_last_idx % rxvq->num].len - sizeof(VirtioNetHdr); + len = rxvq->used->ring[rx_last_idx % rxvq->num].len - virtio_net_hdr_size; if (len > maxlen) { puts("virtio-net: Receive buffer too small"); len = maxlen; } id = rxvq->used->ring[rx_last_idx % rxvq->num].id % rxvq->num; - pkt = (uint8_t *)(rxvq->desc[id].addr + sizeof(VirtioNetHdr)); + pkt = (uint8_t *)(rxvq->desc[id].addr + virtio_net_hdr_size); #if DEBUG_VIRTIO_NET /* Dump packet */ int i; -- 2.55.0