From 3e0629cb6c0518423c9e2671bbe8ec15dde5dcaf Mon Sep 17 00:00:00 2001 From: Jack Morgenstein Date: Thu, 11 Sep 2014 14:11:17 +0300 Subject: [PATCH] IB/mlx4: Avoid accessing netdevice when building RoCE qp1 header The source MAC is needed in RoCE when building the QP1 header. Currently, this is obtained from the source net device. However, the net device may not yet exist, or can be destroyed in parallel to this QP1 send operation (e.g through the VPI port change flow) so accessing it may cause a kernel crash. To fix this, we maintain a source MAC cache per port for the net device in struct mlx4_ib_roce. This cached MAC is initialized to be the default MAC address obtained during HCA initialization via QUERY_PORT. This cached MAC is updated via the netdev event notifier handler. Since the cached MAC is held in an atomic64 object, we do not need locking when accessing it. Signed-off-by: Jack Morgenstein Signed-off-by: Or Gerlitz Signed-off-by: Roland Dreier --- drivers/infiniband/hw/mlx4/main.c | 5 ++++ drivers/infiniband/hw/mlx4/mlx4_ib.h | 1 + drivers/infiniband/hw/mlx4/qp.c | 38 ++++++++++++++++------------ 3 files changed, 28 insertions(+), 16 deletions(-) diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c index c61bcee9ee8a..657ce0f810fd 100644 --- a/drivers/infiniband/hw/mlx4/main.c +++ b/drivers/infiniband/hw/mlx4/main.c @@ -1643,6 +1643,8 @@ static void mlx4_ib_update_qps(struct mlx4_ib_dev *ibdev, new_smac = mlx4_mac_to_u64(dev->dev_addr); read_unlock(&dev_base_lock); + atomic64_set(&ibdev->iboe.mac[port - 1], new_smac); + mutex_lock(&ibdev->qp1_proxy_lock[port - 1]); qp = ibdev->qp1_proxy[port - 1]; if (qp) { @@ -2190,6 +2192,9 @@ static void *mlx4_ib_add(struct mlx4_dev *dev) goto err_steer_free_bitmap; } + for (j = 1; j <= ibdev->dev->caps.num_ports; j++) + atomic64_set(&iboe->mac[j - 1], ibdev->dev->caps.def_mac[j]); + if (ib_register_device(&ibdev->ib_dev, NULL)) goto err_steer_free_bitmap; diff --git a/drivers/infiniband/hw/mlx4/mlx4_ib.h b/drivers/infiniband/hw/mlx4/mlx4_ib.h index e8cad3926bfc..6eb743f65f6f 100644 --- a/drivers/infiniband/hw/mlx4/mlx4_ib.h +++ b/drivers/infiniband/hw/mlx4/mlx4_ib.h @@ -451,6 +451,7 @@ struct mlx4_ib_iboe { spinlock_t lock; struct net_device *netdevs[MLX4_MAX_PORTS]; struct net_device *masters[MLX4_MAX_PORTS]; + atomic64_t mac[MLX4_MAX_PORTS]; struct notifier_block nb; struct notifier_block nb_inet; struct notifier_block nb_inet6; diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c index 67780452f0cf..25e0208588e6 100644 --- a/drivers/infiniband/hw/mlx4/qp.c +++ b/drivers/infiniband/hw/mlx4/qp.c @@ -1390,18 +1390,10 @@ static void update_mcg_macs(struct mlx4_ib_dev *dev, struct mlx4_ib_qp *qp) static int handle_eth_ud_smac_index(struct mlx4_ib_dev *dev, struct mlx4_ib_qp *qp, u8 *smac, struct mlx4_qp_context *context) { - struct net_device *ndev; u64 u64_mac; int smac_index; - - ndev = dev->iboe.netdevs[qp->port - 1]; - if (ndev) { - smac = ndev->dev_addr; - u64_mac = mlx4_mac_to_u64(smac); - } else { - u64_mac = dev->dev->caps.def_mac[qp->port]; - } + u64_mac = atomic64_read(&dev->iboe.mac[qp->port - 1]); context->pri_path.sched_queue = MLX4_IB_DEFAULT_SCHED_QUEUE | ((qp->port - 1) << 6); if (!qp->pri.smac) { @@ -2083,6 +2075,16 @@ static int build_sriov_qp0_header(struct mlx4_ib_sqp *sqp, return 0; } +static void mlx4_u64_to_smac(u8 *dst_mac, u64 src_mac) +{ + int i; + + for (i = ETH_ALEN; i; i--) { + dst_mac[i - 1] = src_mac & 0xff; + src_mac >>= 8; + } +} + static int build_mlx_header(struct mlx4_ib_sqp *sqp, struct ib_send_wr *wr, void *wqe, unsigned *mlx_seg_len) { @@ -2197,7 +2199,6 @@ static int build_mlx_header(struct mlx4_ib_sqp *sqp, struct ib_send_wr *wr, } if (is_eth) { - u8 *smac; struct in6_addr in6; u16 pcp = (be32_to_cpu(ah->av.ib.sl_tclass_flowlabel) >> 29) << 13; @@ -2210,12 +2211,17 @@ static int build_mlx_header(struct mlx4_ib_sqp *sqp, struct ib_send_wr *wr, memcpy(&ctrl->imm, ah->av.eth.mac + 2, 4); memcpy(&in6, sgid.raw, sizeof(in6)); - if (!mlx4_is_mfunc(to_mdev(ib_dev)->dev)) - smac = to_mdev(sqp->qp.ibqp.device)-> - iboe.netdevs[sqp->qp.port - 1]->dev_addr; - else /* use the src mac of the tunnel */ - smac = ah->av.eth.s_mac; - memcpy(sqp->ud_header.eth.smac_h, smac, 6); + if (!mlx4_is_mfunc(to_mdev(ib_dev)->dev)) { + u64 mac = atomic64_read(&to_mdev(ib_dev)->iboe.mac[sqp->qp.port - 1]); + u8 smac[ETH_ALEN]; + + mlx4_u64_to_smac(smac, mac); + memcpy(sqp->ud_header.eth.smac_h, smac, ETH_ALEN); + } else { + /* use the src mac of the tunnel */ + memcpy(sqp->ud_header.eth.smac_h, ah->av.eth.s_mac, ETH_ALEN); + } + if (!memcmp(sqp->ud_header.eth.smac_h, sqp->ud_header.eth.dmac_h, 6)) mlx->flags |= cpu_to_be32(MLX4_WQE_CTRL_FORCE_LOOPBACK); if (!is_vlan) { -- 2.30.2