diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_transport.c | 96 |
1 files changed, 58 insertions, 38 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index f09444c451bc..16fd3f6718ff 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -54,7 +54,6 @@ static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, int flags); static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt); static void svc_rdma_release_rqst(struct svc_rqst *); -static void rdma_destroy_xprt(struct svcxprt_rdma *xprt); static void dto_tasklet_func(unsigned long data); static void svc_rdma_detach(struct svc_xprt *xprt); static void svc_rdma_free(struct svc_xprt *xprt); @@ -247,6 +246,7 @@ static void dto_tasklet_func(unsigned long data) sq_cq_reap(xprt); } + svc_xprt_put(&xprt->sc_xprt); spin_lock_irqsave(&dto_lock, flags); } spin_unlock_irqrestore(&dto_lock, flags); @@ -275,8 +275,10 @@ static void rq_comp_handler(struct ib_cq *cq, void *cq_context) * add it */ spin_lock_irqsave(&dto_lock, flags); - if (list_empty(&xprt->sc_dto_q)) + if (list_empty(&xprt->sc_dto_q)) { + svc_xprt_get(&xprt->sc_xprt); list_add_tail(&xprt->sc_dto_q, &dto_xprt_q); + } spin_unlock_irqrestore(&dto_lock, flags); /* Tasklet does all the work to avoid irqsave locks. */ @@ -386,8 +388,10 @@ static void sq_comp_handler(struct ib_cq *cq, void *cq_context) * add it */ spin_lock_irqsave(&dto_lock, flags); - if (list_empty(&xprt->sc_dto_q)) + if (list_empty(&xprt->sc_dto_q)) { + svc_xprt_get(&xprt->sc_xprt); list_add_tail(&xprt->sc_dto_q, &dto_xprt_q); + } spin_unlock_irqrestore(&dto_lock, flags); /* Tasklet does all the work to avoid irqsave locks. */ @@ -611,6 +615,7 @@ static int rdma_cma_handler(struct rdma_cm_id *cma_id, switch (event->event) { case RDMA_CM_EVENT_ESTABLISHED: /* Accept complete */ + svc_xprt_get(xprt); dprintk("svcrdma: Connection completed on DTO xprt=%p, " "cm_id=%p\n", xprt, cma_id); clear_bit(RDMAXPRT_CONN_PENDING, &rdma->sc_flags); @@ -661,15 +666,15 @@ static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, listen_id = rdma_create_id(rdma_listen_handler, cma_xprt, RDMA_PS_TCP); if (IS_ERR(listen_id)) { - rdma_destroy_xprt(cma_xprt); + svc_xprt_put(&cma_xprt->sc_xprt); dprintk("svcrdma: rdma_create_id failed = %ld\n", PTR_ERR(listen_id)); return (void *)listen_id; } ret = rdma_bind_addr(listen_id, sa); if (ret) { - rdma_destroy_xprt(cma_xprt); rdma_destroy_id(listen_id); + svc_xprt_put(&cma_xprt->sc_xprt); dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret); return ERR_PTR(ret); } @@ -678,8 +683,9 @@ static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG); if (ret) { rdma_destroy_id(listen_id); - rdma_destroy_xprt(cma_xprt); + svc_xprt_put(&cma_xprt->sc_xprt); dprintk("svcrdma: rdma_listen failed = %d\n", ret); + return ERR_PTR(ret); } /* @@ -820,6 +826,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) newxprt->sc_sq_depth = qp_attr.cap.max_send_wr; newxprt->sc_max_requests = qp_attr.cap.max_recv_wr; } + svc_xprt_get(&newxprt->sc_xprt); newxprt->sc_qp = newxprt->sc_cm_id->qp; /* Register all of physical memory */ @@ -891,8 +898,15 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) errout: dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret); + /* Take a reference in case the DTO handler runs */ + svc_xprt_get(&newxprt->sc_xprt); + if (newxprt->sc_qp && !IS_ERR(newxprt->sc_qp)) { + ib_destroy_qp(newxprt->sc_qp); + svc_xprt_put(&newxprt->sc_xprt); + } rdma_destroy_id(newxprt->sc_cm_id); - rdma_destroy_xprt(newxprt); + /* This call to put will destroy the transport */ + svc_xprt_put(&newxprt->sc_xprt); return NULL; } @@ -919,54 +933,60 @@ static void svc_rdma_release_rqst(struct svc_rqst *rqstp) rqstp->rq_xprt_ctxt = NULL; } -/* Disable data ready events for this connection */ +/* + * When connected, an svc_xprt has at least three references: + * + * - A reference held by the QP. We still hold that here because this + * code deletes the QP and puts the reference. + * + * - A reference held by the cm_id between the ESTABLISHED and + * DISCONNECTED events. If the remote peer disconnected first, this + * reference could be gone. + * + * - A reference held by the svc_recv code that called this function + * as part of close processing. + * + * At a minimum two references should still be held. + */ static void svc_rdma_detach(struct svc_xprt *xprt) { struct svcxprt_rdma *rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt); - unsigned long flags; - dprintk("svc: svc_rdma_detach(%p)\n", xprt); - /* - * Shutdown the connection. This will ensure we don't get any - * more events from the provider. - */ + + /* Disconnect and flush posted WQE */ rdma_disconnect(rdma->sc_cm_id); - rdma_destroy_id(rdma->sc_cm_id); - /* We may already be on the DTO list */ - spin_lock_irqsave(&dto_lock, flags); - if (!list_empty(&rdma->sc_dto_q)) - list_del_init(&rdma->sc_dto_q); - spin_unlock_irqrestore(&dto_lock, flags); + /* Destroy the QP if present (not a listener) */ + if (rdma->sc_qp && !IS_ERR(rdma->sc_qp)) { + ib_destroy_qp(rdma->sc_qp); + svc_xprt_put(xprt); + } + + /* Destroy the CM ID */ + rdma_destroy_id(rdma->sc_cm_id); } static void svc_rdma_free(struct svc_xprt *xprt) { struct svcxprt_rdma *rdma = (struct svcxprt_rdma *)xprt; dprintk("svcrdma: svc_rdma_free(%p)\n", rdma); - rdma_destroy_xprt(rdma); - kfree(rdma); -} - -static void rdma_destroy_xprt(struct svcxprt_rdma *xprt) -{ - if (xprt->sc_qp && !IS_ERR(xprt->sc_qp)) - ib_destroy_qp(xprt->sc_qp); - - if (xprt->sc_sq_cq && !IS_ERR(xprt->sc_sq_cq)) - ib_destroy_cq(xprt->sc_sq_cq); + /* We should only be called from kref_put */ + BUG_ON(atomic_read(&xprt->xpt_ref.refcount) != 0); + if (rdma->sc_sq_cq && !IS_ERR(rdma->sc_sq_cq)) + ib_destroy_cq(rdma->sc_sq_cq); - if (xprt->sc_rq_cq && !IS_ERR(xprt->sc_rq_cq)) - ib_destroy_cq(xprt->sc_rq_cq); + if (rdma->sc_rq_cq && !IS_ERR(rdma->sc_rq_cq)) + ib_destroy_cq(rdma->sc_rq_cq); - if (xprt->sc_phys_mr && !IS_ERR(xprt->sc_phys_mr)) - ib_dereg_mr(xprt->sc_phys_mr); + if (rdma->sc_phys_mr && !IS_ERR(rdma->sc_phys_mr)) + ib_dereg_mr(rdma->sc_phys_mr); - if (xprt->sc_pd && !IS_ERR(xprt->sc_pd)) - ib_dealloc_pd(xprt->sc_pd); + if (rdma->sc_pd && !IS_ERR(rdma->sc_pd)) + ib_dealloc_pd(rdma->sc_pd); - destroy_context_cache(xprt->sc_ctxt_head); + destroy_context_cache(rdma->sc_ctxt_head); + kfree(rdma); } static int svc_rdma_has_wspace(struct svc_xprt *xprt) |