diff --git a/drivers/infiniband/core/rw.c b/drivers/infiniband/core/rw.c index 2c148457b589..518095d82d5d 100644 --- a/drivers/infiniband/core/rw.c +++ b/drivers/infiniband/core/rw.c @@ -1071,34 +1071,57 @@ unsigned int rdma_rw_mr_factor(struct ib_device *device, u32 port_num, } EXPORT_SYMBOL(rdma_rw_mr_factor); +/** + * rdma_rw_max_send_wr - compute max Send WRs needed for RDMA R/W contexts + * @dev: RDMA device + * @port_num: port number + * @max_rdma_ctxs: number of rdma_rw_ctx structures + * @create_flags: QP create flags (pass IB_QP_CREATE_INTEGRITY_EN if + * data integrity will be enabled on the QP) + * + * Returns the total number of Send Queue entries needed for + * @max_rdma_ctxs. The result accounts for memory registration and + * invalidation work requests when the device requires them. + * + * ULPs use this to size Send Queues and Send CQs before creating a + * Queue Pair. + */ +unsigned int rdma_rw_max_send_wr(struct ib_device *dev, u32 port_num, + unsigned int max_rdma_ctxs, u32 create_flags) +{ + unsigned int factor = 1; + unsigned int result; + + if (create_flags & IB_QP_CREATE_INTEGRITY_EN || + rdma_rw_can_use_mr(dev, port_num)) + factor += 2; /* reg + inv */ + + if (check_mul_overflow(factor, max_rdma_ctxs, &result)) + return UINT_MAX; + return result; +} +EXPORT_SYMBOL(rdma_rw_max_send_wr); + void rdma_rw_init_qp(struct ib_device *dev, struct ib_qp_init_attr *attr) { - u32 factor; + unsigned int factor = 1; WARN_ON_ONCE(attr->port_num == 0); /* - * Each context needs at least one RDMA READ or WRITE WR. - * - * For some hardware we might need more, eventually we should ask the - * HCA driver for a multiplier here. - */ - factor = 1; - - /* - * If the device needs MRs to perform RDMA READ or WRITE operations, - * we'll need two additional MRs for the registrations and the - * invalidation. + * If the device uses MRs to perform RDMA READ or WRITE operations, + * or if data integrity is enabled, account for registration and + * invalidation work requests. */ if (attr->create_flags & IB_QP_CREATE_INTEGRITY_EN || rdma_rw_can_use_mr(dev, attr->port_num)) - factor += 2; /* inv + reg */ + factor += 2; /* reg + inv */ attr->cap.max_send_wr += factor * attr->cap.max_rdma_ctxs; /* - * But maybe we were just too high in the sky and the device doesn't - * even support all we need, and we'll have to live with what we get.. + * The device might not support all we need, and we'll have to + * live with what we get. */ attr->cap.max_send_wr = min_t(u32, attr->cap.max_send_wr, dev->attrs.max_qp_wr); diff --git a/include/rdma/rw.h b/include/rdma/rw.h index 3400c017bfb6..6a1d08614e09 100644 --- a/include/rdma/rw.h +++ b/include/rdma/rw.h @@ -86,6 +86,8 @@ int rdma_rw_ctx_post(struct rdma_rw_ctx *ctx, struct ib_qp *qp, u32 port_num, unsigned int rdma_rw_mr_factor(struct ib_device *device, u32 port_num, unsigned int maxpages); +unsigned int rdma_rw_max_send_wr(struct ib_device *dev, u32 port_num, + unsigned int max_rdma_ctxs, u32 create_flags); void rdma_rw_init_qp(struct ib_device *dev, struct ib_qp_init_attr *attr); int rdma_rw_init_mrs(struct ib_qp *qp, struct ib_qp_init_attr *attr); void rdma_rw_cleanup_mrs(struct ib_qp *qp); diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index b7b318ad25c4..9b623849723e 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -462,7 +462,10 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) newxprt->sc_max_bc_requests = 2; } - /* Arbitrary estimate of the needed number of rdma_rw contexts. + /* Estimate the needed number of rdma_rw contexts. The maximum + * Read and Write chunks have one segment each. Each request + * can involve one Read chunk and either a Write chunk or Reply + * chunk; thus a factor of three. */ maxpayload = min(xprt->xpt_server->sv_max_payload, RPCSVC_MAXPAYLOAD_RDMA); @@ -470,7 +473,8 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) rdma_rw_mr_factor(dev, newxprt->sc_port_num, maxpayload >> PAGE_SHIFT); - newxprt->sc_sq_depth = rq_depth + ctxts; + newxprt->sc_sq_depth = rq_depth + + rdma_rw_max_send_wr(dev, newxprt->sc_port_num, ctxts, 0); if (newxprt->sc_sq_depth > dev->attrs.max_qp_wr) newxprt->sc_sq_depth = dev->attrs.max_qp_wr; atomic_set(&newxprt->sc_sq_avail, newxprt->sc_sq_depth);