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- // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
- /*
- * Copyright (c) 2014-2017 Oracle. All rights reserved.
- * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
- *
- * This software is available to you under a choice of one of two
- * licenses. You may choose to be licensed under the terms of the GNU
- * General Public License (GPL) Version 2, available from the file
- * COPYING in the main directory of this source tree, or the BSD-type
- * license below:
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following
- * disclaimer in the documentation and/or other materials provided
- * with the distribution.
- *
- * Neither the name of the Network Appliance, Inc. nor the names of
- * its contributors may be used to endorse or promote products
- * derived from this software without specific prior written
- * permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
- /*
- * verbs.c
- *
- * Encapsulates the major functions managing:
- * o adapters
- * o endpoints
- * o connections
- * o buffer memory
- */
- #include <linux/interrupt.h>
- #include <linux/slab.h>
- #include <linux/sunrpc/addr.h>
- #include <linux/sunrpc/svc_rdma.h>
- #include <linux/log2.h>
- #include <asm-generic/barrier.h>
- #include <asm/bitops.h>
- #include <rdma/ib_cm.h>
- #include "xprt_rdma.h"
- #include <trace/events/rpcrdma.h>
- /*
- * Globals/Macros
- */
- #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
- # define RPCDBG_FACILITY RPCDBG_TRANS
- #endif
- /*
- * internal functions
- */
- static int rpcrdma_sendctxs_create(struct rpcrdma_xprt *r_xprt);
- static void rpcrdma_sendctxs_destroy(struct rpcrdma_xprt *r_xprt);
- static void rpcrdma_sendctx_put_locked(struct rpcrdma_xprt *r_xprt,
- struct rpcrdma_sendctx *sc);
- static int rpcrdma_reqs_setup(struct rpcrdma_xprt *r_xprt);
- static void rpcrdma_reqs_reset(struct rpcrdma_xprt *r_xprt);
- static void rpcrdma_rep_destroy(struct rpcrdma_rep *rep);
- static void rpcrdma_reps_unmap(struct rpcrdma_xprt *r_xprt);
- static void rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt);
- static void rpcrdma_mrs_destroy(struct rpcrdma_xprt *r_xprt);
- static void rpcrdma_ep_get(struct rpcrdma_ep *ep);
- static int rpcrdma_ep_put(struct rpcrdma_ep *ep);
- static struct rpcrdma_regbuf *
- rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction,
- gfp_t flags);
- static void rpcrdma_regbuf_dma_unmap(struct rpcrdma_regbuf *rb);
- static void rpcrdma_regbuf_free(struct rpcrdma_regbuf *rb);
- /* Wait for outstanding transport work to finish. ib_drain_qp
- * handles the drains in the wrong order for us, so open code
- * them here.
- */
- static void rpcrdma_xprt_drain(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_ep *ep = r_xprt->rx_ep;
- struct rdma_cm_id *id = ep->re_id;
- /* Flush Receives, then wait for deferred Reply work
- * to complete.
- */
- ib_drain_rq(id->qp);
- /* Deferred Reply processing might have scheduled
- * local invalidations.
- */
- ib_drain_sq(id->qp);
- rpcrdma_ep_put(ep);
- }
- /**
- * rpcrdma_qp_event_handler - Handle one QP event (error notification)
- * @event: details of the event
- * @context: ep that owns QP where event occurred
- *
- * Called from the RDMA provider (device driver) possibly in an interrupt
- * context. The QP is always destroyed before the ID, so the ID will be
- * reliably available when this handler is invoked.
- */
- static void rpcrdma_qp_event_handler(struct ib_event *event, void *context)
- {
- struct rpcrdma_ep *ep = context;
- trace_xprtrdma_qp_event(ep, event);
- }
- /* Ensure xprt_force_disconnect() is invoked exactly once when a
- * connection is closed or lost. (The important thing is it needs
- * to be invoked "at least" once).
- */
- static void rpcrdma_force_disconnect(struct rpcrdma_ep *ep)
- {
- if (atomic_add_unless(&ep->re_force_disconnect, 1, 1))
- xprt_force_disconnect(ep->re_xprt);
- }
- /**
- * rpcrdma_flush_disconnect - Disconnect on flushed completion
- * @r_xprt: transport to disconnect
- * @wc: work completion entry
- *
- * Must be called in process context.
- */
- void rpcrdma_flush_disconnect(struct rpcrdma_xprt *r_xprt, struct ib_wc *wc)
- {
- if (wc->status != IB_WC_SUCCESS)
- rpcrdma_force_disconnect(r_xprt->rx_ep);
- }
- /**
- * rpcrdma_wc_send - Invoked by RDMA provider for each polled Send WC
- * @cq: completion queue
- * @wc: WCE for a completed Send WR
- *
- */
- static void rpcrdma_wc_send(struct ib_cq *cq, struct ib_wc *wc)
- {
- struct ib_cqe *cqe = wc->wr_cqe;
- struct rpcrdma_sendctx *sc =
- container_of(cqe, struct rpcrdma_sendctx, sc_cqe);
- struct rpcrdma_xprt *r_xprt = cq->cq_context;
- /* WARNING: Only wr_cqe and status are reliable at this point */
- trace_xprtrdma_wc_send(sc, wc);
- rpcrdma_sendctx_put_locked(r_xprt, sc);
- rpcrdma_flush_disconnect(r_xprt, wc);
- }
- /**
- * rpcrdma_wc_receive - Invoked by RDMA provider for each polled Receive WC
- * @cq: completion queue
- * @wc: WCE for a completed Receive WR
- *
- */
- static void rpcrdma_wc_receive(struct ib_cq *cq, struct ib_wc *wc)
- {
- struct ib_cqe *cqe = wc->wr_cqe;
- struct rpcrdma_rep *rep = container_of(cqe, struct rpcrdma_rep,
- rr_cqe);
- struct rpcrdma_xprt *r_xprt = cq->cq_context;
- /* WARNING: Only wr_cqe and status are reliable at this point */
- trace_xprtrdma_wc_receive(wc);
- --r_xprt->rx_ep->re_receive_count;
- if (wc->status != IB_WC_SUCCESS)
- goto out_flushed;
- /* status == SUCCESS means all fields in wc are trustworthy */
- rpcrdma_set_xdrlen(&rep->rr_hdrbuf, wc->byte_len);
- rep->rr_wc_flags = wc->wc_flags;
- rep->rr_inv_rkey = wc->ex.invalidate_rkey;
- ib_dma_sync_single_for_cpu(rdmab_device(rep->rr_rdmabuf),
- rdmab_addr(rep->rr_rdmabuf),
- wc->byte_len, DMA_FROM_DEVICE);
- rpcrdma_reply_handler(rep);
- return;
- out_flushed:
- rpcrdma_flush_disconnect(r_xprt, wc);
- rpcrdma_rep_destroy(rep);
- }
- static void rpcrdma_update_cm_private(struct rpcrdma_ep *ep,
- struct rdma_conn_param *param)
- {
- const struct rpcrdma_connect_private *pmsg = param->private_data;
- unsigned int rsize, wsize;
- /* Default settings for RPC-over-RDMA Version One */
- ep->re_implicit_roundup = xprt_rdma_pad_optimize;
- rsize = RPCRDMA_V1_DEF_INLINE_SIZE;
- wsize = RPCRDMA_V1_DEF_INLINE_SIZE;
- if (pmsg &&
- pmsg->cp_magic == rpcrdma_cmp_magic &&
- pmsg->cp_version == RPCRDMA_CMP_VERSION) {
- ep->re_implicit_roundup = true;
- rsize = rpcrdma_decode_buffer_size(pmsg->cp_send_size);
- wsize = rpcrdma_decode_buffer_size(pmsg->cp_recv_size);
- }
- if (rsize < ep->re_inline_recv)
- ep->re_inline_recv = rsize;
- if (wsize < ep->re_inline_send)
- ep->re_inline_send = wsize;
- rpcrdma_set_max_header_sizes(ep);
- }
- /**
- * rpcrdma_cm_event_handler - Handle RDMA CM events
- * @id: rdma_cm_id on which an event has occurred
- * @event: details of the event
- *
- * Called with @id's mutex held. Returns 1 if caller should
- * destroy @id, otherwise 0.
- */
- static int
- rpcrdma_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event)
- {
- struct sockaddr *sap = (struct sockaddr *)&id->route.addr.dst_addr;
- struct rpcrdma_ep *ep = id->context;
- might_sleep();
- switch (event->event) {
- case RDMA_CM_EVENT_ADDR_RESOLVED:
- case RDMA_CM_EVENT_ROUTE_RESOLVED:
- ep->re_async_rc = 0;
- complete(&ep->re_done);
- return 0;
- case RDMA_CM_EVENT_ADDR_ERROR:
- ep->re_async_rc = -EPROTO;
- complete(&ep->re_done);
- return 0;
- case RDMA_CM_EVENT_ROUTE_ERROR:
- ep->re_async_rc = -ENETUNREACH;
- complete(&ep->re_done);
- return 0;
- case RDMA_CM_EVENT_DEVICE_REMOVAL:
- pr_info("rpcrdma: removing device %s for %pISpc\n",
- ep->re_id->device->name, sap);
- fallthrough;
- case RDMA_CM_EVENT_ADDR_CHANGE:
- ep->re_connect_status = -ENODEV;
- goto disconnected;
- case RDMA_CM_EVENT_ESTABLISHED:
- rpcrdma_ep_get(ep);
- ep->re_connect_status = 1;
- rpcrdma_update_cm_private(ep, &event->param.conn);
- trace_xprtrdma_inline_thresh(ep);
- wake_up_all(&ep->re_connect_wait);
- break;
- case RDMA_CM_EVENT_CONNECT_ERROR:
- ep->re_connect_status = -ENOTCONN;
- goto wake_connect_worker;
- case RDMA_CM_EVENT_UNREACHABLE:
- ep->re_connect_status = -ENETUNREACH;
- goto wake_connect_worker;
- case RDMA_CM_EVENT_REJECTED:
- dprintk("rpcrdma: connection to %pISpc rejected: %s\n",
- sap, rdma_reject_msg(id, event->status));
- ep->re_connect_status = -ECONNREFUSED;
- if (event->status == IB_CM_REJ_STALE_CONN)
- ep->re_connect_status = -ENOTCONN;
- wake_connect_worker:
- wake_up_all(&ep->re_connect_wait);
- return 0;
- case RDMA_CM_EVENT_DISCONNECTED:
- ep->re_connect_status = -ECONNABORTED;
- disconnected:
- rpcrdma_force_disconnect(ep);
- return rpcrdma_ep_put(ep);
- default:
- break;
- }
- dprintk("RPC: %s: %pISpc on %s/frwr: %s\n", __func__, sap,
- ep->re_id->device->name, rdma_event_msg(event->event));
- return 0;
- }
- static struct rdma_cm_id *rpcrdma_create_id(struct rpcrdma_xprt *r_xprt,
- struct rpcrdma_ep *ep)
- {
- unsigned long wtimeout = msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT) + 1;
- struct rpc_xprt *xprt = &r_xprt->rx_xprt;
- struct rdma_cm_id *id;
- int rc;
- init_completion(&ep->re_done);
- id = rdma_create_id(xprt->xprt_net, rpcrdma_cm_event_handler, ep,
- RDMA_PS_TCP, IB_QPT_RC);
- if (IS_ERR(id))
- return id;
- ep->re_async_rc = -ETIMEDOUT;
- rc = rdma_resolve_addr(id, NULL, (struct sockaddr *)&xprt->addr,
- RDMA_RESOLVE_TIMEOUT);
- if (rc)
- goto out;
- rc = wait_for_completion_interruptible_timeout(&ep->re_done, wtimeout);
- if (rc < 0)
- goto out;
- rc = ep->re_async_rc;
- if (rc)
- goto out;
- ep->re_async_rc = -ETIMEDOUT;
- rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT);
- if (rc)
- goto out;
- rc = wait_for_completion_interruptible_timeout(&ep->re_done, wtimeout);
- if (rc < 0)
- goto out;
- rc = ep->re_async_rc;
- if (rc)
- goto out;
- return id;
- out:
- rdma_destroy_id(id);
- return ERR_PTR(rc);
- }
- static void rpcrdma_ep_destroy(struct kref *kref)
- {
- struct rpcrdma_ep *ep = container_of(kref, struct rpcrdma_ep, re_kref);
- if (ep->re_id->qp) {
- rdma_destroy_qp(ep->re_id);
- ep->re_id->qp = NULL;
- }
- if (ep->re_attr.recv_cq)
- ib_free_cq(ep->re_attr.recv_cq);
- ep->re_attr.recv_cq = NULL;
- if (ep->re_attr.send_cq)
- ib_free_cq(ep->re_attr.send_cq);
- ep->re_attr.send_cq = NULL;
- if (ep->re_pd)
- ib_dealloc_pd(ep->re_pd);
- ep->re_pd = NULL;
- kfree(ep);
- module_put(THIS_MODULE);
- }
- static noinline void rpcrdma_ep_get(struct rpcrdma_ep *ep)
- {
- kref_get(&ep->re_kref);
- }
- /* Returns:
- * %0 if @ep still has a positive kref count, or
- * %1 if @ep was destroyed successfully.
- */
- static noinline int rpcrdma_ep_put(struct rpcrdma_ep *ep)
- {
- return kref_put(&ep->re_kref, rpcrdma_ep_destroy);
- }
- static int rpcrdma_ep_create(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_connect_private *pmsg;
- struct ib_device *device;
- struct rdma_cm_id *id;
- struct rpcrdma_ep *ep;
- int rc;
- ep = kzalloc(sizeof(*ep), GFP_NOFS);
- if (!ep)
- return -ENOTCONN;
- ep->re_xprt = &r_xprt->rx_xprt;
- kref_init(&ep->re_kref);
- id = rpcrdma_create_id(r_xprt, ep);
- if (IS_ERR(id)) {
- kfree(ep);
- return PTR_ERR(id);
- }
- __module_get(THIS_MODULE);
- device = id->device;
- ep->re_id = id;
- ep->re_max_requests = r_xprt->rx_xprt.max_reqs;
- ep->re_inline_send = xprt_rdma_max_inline_write;
- ep->re_inline_recv = xprt_rdma_max_inline_read;
- rc = frwr_query_device(ep, device);
- if (rc)
- goto out_destroy;
- r_xprt->rx_buf.rb_max_requests = cpu_to_be32(ep->re_max_requests);
- ep->re_attr.event_handler = rpcrdma_qp_event_handler;
- ep->re_attr.qp_context = ep;
- ep->re_attr.srq = NULL;
- ep->re_attr.cap.max_inline_data = 0;
- ep->re_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
- ep->re_attr.qp_type = IB_QPT_RC;
- ep->re_attr.port_num = ~0;
- dprintk("RPC: %s: requested max: dtos: send %d recv %d; "
- "iovs: send %d recv %d\n",
- __func__,
- ep->re_attr.cap.max_send_wr,
- ep->re_attr.cap.max_recv_wr,
- ep->re_attr.cap.max_send_sge,
- ep->re_attr.cap.max_recv_sge);
- ep->re_send_batch = ep->re_max_requests >> 3;
- ep->re_send_count = ep->re_send_batch;
- init_waitqueue_head(&ep->re_connect_wait);
- ep->re_attr.send_cq = ib_alloc_cq_any(device, r_xprt,
- ep->re_attr.cap.max_send_wr,
- IB_POLL_WORKQUEUE);
- if (IS_ERR(ep->re_attr.send_cq)) {
- rc = PTR_ERR(ep->re_attr.send_cq);
- ep->re_attr.send_cq = NULL;
- goto out_destroy;
- }
- ep->re_attr.recv_cq = ib_alloc_cq_any(device, r_xprt,
- ep->re_attr.cap.max_recv_wr,
- IB_POLL_WORKQUEUE);
- if (IS_ERR(ep->re_attr.recv_cq)) {
- rc = PTR_ERR(ep->re_attr.recv_cq);
- ep->re_attr.recv_cq = NULL;
- goto out_destroy;
- }
- ep->re_receive_count = 0;
- /* Initialize cma parameters */
- memset(&ep->re_remote_cma, 0, sizeof(ep->re_remote_cma));
- /* Prepare RDMA-CM private message */
- pmsg = &ep->re_cm_private;
- pmsg->cp_magic = rpcrdma_cmp_magic;
- pmsg->cp_version = RPCRDMA_CMP_VERSION;
- pmsg->cp_flags |= RPCRDMA_CMP_F_SND_W_INV_OK;
- pmsg->cp_send_size = rpcrdma_encode_buffer_size(ep->re_inline_send);
- pmsg->cp_recv_size = rpcrdma_encode_buffer_size(ep->re_inline_recv);
- ep->re_remote_cma.private_data = pmsg;
- ep->re_remote_cma.private_data_len = sizeof(*pmsg);
- /* Client offers RDMA Read but does not initiate */
- ep->re_remote_cma.initiator_depth = 0;
- ep->re_remote_cma.responder_resources =
- min_t(int, U8_MAX, device->attrs.max_qp_rd_atom);
- /* Limit transport retries so client can detect server
- * GID changes quickly. RPC layer handles re-establishing
- * transport connection and retransmission.
- */
- ep->re_remote_cma.retry_count = 6;
- /* RPC-over-RDMA handles its own flow control. In addition,
- * make all RNR NAKs visible so we know that RPC-over-RDMA
- * flow control is working correctly (no NAKs should be seen).
- */
- ep->re_remote_cma.flow_control = 0;
- ep->re_remote_cma.rnr_retry_count = 0;
- ep->re_pd = ib_alloc_pd(device, 0);
- if (IS_ERR(ep->re_pd)) {
- rc = PTR_ERR(ep->re_pd);
- ep->re_pd = NULL;
- goto out_destroy;
- }
- rc = rdma_create_qp(id, ep->re_pd, &ep->re_attr);
- if (rc)
- goto out_destroy;
- r_xprt->rx_ep = ep;
- return 0;
- out_destroy:
- rpcrdma_ep_put(ep);
- rdma_destroy_id(id);
- return rc;
- }
- /**
- * rpcrdma_xprt_connect - Connect an unconnected transport
- * @r_xprt: controlling transport instance
- *
- * Returns 0 on success or a negative errno.
- */
- int rpcrdma_xprt_connect(struct rpcrdma_xprt *r_xprt)
- {
- struct rpc_xprt *xprt = &r_xprt->rx_xprt;
- struct rpcrdma_ep *ep;
- int rc;
- rc = rpcrdma_ep_create(r_xprt);
- if (rc)
- return rc;
- ep = r_xprt->rx_ep;
- xprt_clear_connected(xprt);
- rpcrdma_reset_cwnd(r_xprt);
- /* Bump the ep's reference count while there are
- * outstanding Receives.
- */
- rpcrdma_ep_get(ep);
- rpcrdma_post_recvs(r_xprt, 1, true);
- rc = rdma_connect(ep->re_id, &ep->re_remote_cma);
- if (rc)
- goto out;
- if (xprt->reestablish_timeout < RPCRDMA_INIT_REEST_TO)
- xprt->reestablish_timeout = RPCRDMA_INIT_REEST_TO;
- wait_event_interruptible(ep->re_connect_wait,
- ep->re_connect_status != 0);
- if (ep->re_connect_status <= 0) {
- rc = ep->re_connect_status;
- goto out;
- }
- rc = rpcrdma_sendctxs_create(r_xprt);
- if (rc) {
- rc = -ENOTCONN;
- goto out;
- }
- rc = rpcrdma_reqs_setup(r_xprt);
- if (rc) {
- rc = -ENOTCONN;
- goto out;
- }
- rpcrdma_mrs_create(r_xprt);
- out:
- trace_xprtrdma_connect(r_xprt, rc);
- return rc;
- }
- /**
- * rpcrdma_xprt_disconnect - Disconnect underlying transport
- * @r_xprt: controlling transport instance
- *
- * Caller serializes. Either the transport send lock is held,
- * or we're being called to destroy the transport.
- *
- * On return, @r_xprt is completely divested of all hardware
- * resources and prepared for the next ->connect operation.
- */
- void rpcrdma_xprt_disconnect(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_ep *ep = r_xprt->rx_ep;
- struct rdma_cm_id *id;
- int rc;
- if (!ep)
- return;
- id = ep->re_id;
- rc = rdma_disconnect(id);
- trace_xprtrdma_disconnect(r_xprt, rc);
- rpcrdma_xprt_drain(r_xprt);
- rpcrdma_reps_unmap(r_xprt);
- rpcrdma_reqs_reset(r_xprt);
- rpcrdma_mrs_destroy(r_xprt);
- rpcrdma_sendctxs_destroy(r_xprt);
- if (rpcrdma_ep_put(ep))
- rdma_destroy_id(id);
- r_xprt->rx_ep = NULL;
- }
- /* Fixed-size circular FIFO queue. This implementation is wait-free and
- * lock-free.
- *
- * Consumer is the code path that posts Sends. This path dequeues a
- * sendctx for use by a Send operation. Multiple consumer threads
- * are serialized by the RPC transport lock, which allows only one
- * ->send_request call at a time.
- *
- * Producer is the code path that handles Send completions. This path
- * enqueues a sendctx that has been completed. Multiple producer
- * threads are serialized by the ib_poll_cq() function.
- */
- /* rpcrdma_sendctxs_destroy() assumes caller has already quiesced
- * queue activity, and rpcrdma_xprt_drain has flushed all remaining
- * Send requests.
- */
- static void rpcrdma_sendctxs_destroy(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- unsigned long i;
- if (!buf->rb_sc_ctxs)
- return;
- for (i = 0; i <= buf->rb_sc_last; i++)
- kfree(buf->rb_sc_ctxs[i]);
- kfree(buf->rb_sc_ctxs);
- buf->rb_sc_ctxs = NULL;
- }
- static struct rpcrdma_sendctx *rpcrdma_sendctx_create(struct rpcrdma_ep *ep)
- {
- struct rpcrdma_sendctx *sc;
- sc = kzalloc(struct_size(sc, sc_sges, ep->re_attr.cap.max_send_sge),
- GFP_KERNEL);
- if (!sc)
- return NULL;
- sc->sc_cqe.done = rpcrdma_wc_send;
- return sc;
- }
- static int rpcrdma_sendctxs_create(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_sendctx *sc;
- unsigned long i;
- /* Maximum number of concurrent outstanding Send WRs. Capping
- * the circular queue size stops Send Queue overflow by causing
- * the ->send_request call to fail temporarily before too many
- * Sends are posted.
- */
- i = r_xprt->rx_ep->re_max_requests + RPCRDMA_MAX_BC_REQUESTS;
- buf->rb_sc_ctxs = kcalloc(i, sizeof(sc), GFP_KERNEL);
- if (!buf->rb_sc_ctxs)
- return -ENOMEM;
- buf->rb_sc_last = i - 1;
- for (i = 0; i <= buf->rb_sc_last; i++) {
- sc = rpcrdma_sendctx_create(r_xprt->rx_ep);
- if (!sc)
- return -ENOMEM;
- buf->rb_sc_ctxs[i] = sc;
- }
- buf->rb_sc_head = 0;
- buf->rb_sc_tail = 0;
- return 0;
- }
- /* The sendctx queue is not guaranteed to have a size that is a
- * power of two, thus the helpers in circ_buf.h cannot be used.
- * The other option is to use modulus (%), which can be expensive.
- */
- static unsigned long rpcrdma_sendctx_next(struct rpcrdma_buffer *buf,
- unsigned long item)
- {
- return likely(item < buf->rb_sc_last) ? item + 1 : 0;
- }
- /**
- * rpcrdma_sendctx_get_locked - Acquire a send context
- * @r_xprt: controlling transport instance
- *
- * Returns pointer to a free send completion context; or NULL if
- * the queue is empty.
- *
- * Usage: Called to acquire an SGE array before preparing a Send WR.
- *
- * The caller serializes calls to this function (per transport), and
- * provides an effective memory barrier that flushes the new value
- * of rb_sc_head.
- */
- struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_sendctx *sc;
- unsigned long next_head;
- next_head = rpcrdma_sendctx_next(buf, buf->rb_sc_head);
- if (next_head == READ_ONCE(buf->rb_sc_tail))
- goto out_emptyq;
- /* ORDER: item must be accessed _before_ head is updated */
- sc = buf->rb_sc_ctxs[next_head];
- /* Releasing the lock in the caller acts as a memory
- * barrier that flushes rb_sc_head.
- */
- buf->rb_sc_head = next_head;
- return sc;
- out_emptyq:
- /* The queue is "empty" if there have not been enough Send
- * completions recently. This is a sign the Send Queue is
- * backing up. Cause the caller to pause and try again.
- */
- xprt_wait_for_buffer_space(&r_xprt->rx_xprt);
- r_xprt->rx_stats.empty_sendctx_q++;
- return NULL;
- }
- /**
- * rpcrdma_sendctx_put_locked - Release a send context
- * @r_xprt: controlling transport instance
- * @sc: send context to release
- *
- * Usage: Called from Send completion to return a sendctxt
- * to the queue.
- *
- * The caller serializes calls to this function (per transport).
- */
- static void rpcrdma_sendctx_put_locked(struct rpcrdma_xprt *r_xprt,
- struct rpcrdma_sendctx *sc)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- unsigned long next_tail;
- /* Unmap SGEs of previously completed but unsignaled
- * Sends by walking up the queue until @sc is found.
- */
- next_tail = buf->rb_sc_tail;
- do {
- next_tail = rpcrdma_sendctx_next(buf, next_tail);
- /* ORDER: item must be accessed _before_ tail is updated */
- rpcrdma_sendctx_unmap(buf->rb_sc_ctxs[next_tail]);
- } while (buf->rb_sc_ctxs[next_tail] != sc);
- /* Paired with READ_ONCE */
- smp_store_release(&buf->rb_sc_tail, next_tail);
- xprt_write_space(&r_xprt->rx_xprt);
- }
- static void
- rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_ep *ep = r_xprt->rx_ep;
- unsigned int count;
- for (count = 0; count < ep->re_max_rdma_segs; count++) {
- struct rpcrdma_mr *mr;
- int rc;
- mr = kzalloc(sizeof(*mr), GFP_NOFS);
- if (!mr)
- break;
- rc = frwr_mr_init(r_xprt, mr);
- if (rc) {
- kfree(mr);
- break;
- }
- spin_lock(&buf->rb_lock);
- rpcrdma_mr_push(mr, &buf->rb_mrs);
- list_add(&mr->mr_all, &buf->rb_all_mrs);
- spin_unlock(&buf->rb_lock);
- }
- r_xprt->rx_stats.mrs_allocated += count;
- trace_xprtrdma_createmrs(r_xprt, count);
- }
- static void
- rpcrdma_mr_refresh_worker(struct work_struct *work)
- {
- struct rpcrdma_buffer *buf = container_of(work, struct rpcrdma_buffer,
- rb_refresh_worker);
- struct rpcrdma_xprt *r_xprt = container_of(buf, struct rpcrdma_xprt,
- rx_buf);
- rpcrdma_mrs_create(r_xprt);
- xprt_write_space(&r_xprt->rx_xprt);
- }
- /**
- * rpcrdma_mrs_refresh - Wake the MR refresh worker
- * @r_xprt: controlling transport instance
- *
- */
- void rpcrdma_mrs_refresh(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_ep *ep = r_xprt->rx_ep;
- /* If there is no underlying connection, it's no use
- * to wake the refresh worker.
- */
- if (ep->re_connect_status == 1) {
- /* The work is scheduled on a WQ_MEM_RECLAIM
- * workqueue in order to prevent MR allocation
- * from recursing into NFS during direct reclaim.
- */
- queue_work(xprtiod_workqueue, &buf->rb_refresh_worker);
- }
- }
- /**
- * rpcrdma_req_create - Allocate an rpcrdma_req object
- * @r_xprt: controlling r_xprt
- * @size: initial size, in bytes, of send and receive buffers
- * @flags: GFP flags passed to memory allocators
- *
- * Returns an allocated and fully initialized rpcrdma_req or NULL.
- */
- struct rpcrdma_req *rpcrdma_req_create(struct rpcrdma_xprt *r_xprt, size_t size,
- gfp_t flags)
- {
- struct rpcrdma_buffer *buffer = &r_xprt->rx_buf;
- struct rpcrdma_req *req;
- req = kzalloc(sizeof(*req), flags);
- if (req == NULL)
- goto out1;
- req->rl_sendbuf = rpcrdma_regbuf_alloc(size, DMA_TO_DEVICE, flags);
- if (!req->rl_sendbuf)
- goto out2;
- req->rl_recvbuf = rpcrdma_regbuf_alloc(size, DMA_NONE, flags);
- if (!req->rl_recvbuf)
- goto out3;
- INIT_LIST_HEAD(&req->rl_free_mrs);
- INIT_LIST_HEAD(&req->rl_registered);
- spin_lock(&buffer->rb_lock);
- list_add(&req->rl_all, &buffer->rb_allreqs);
- spin_unlock(&buffer->rb_lock);
- return req;
- out3:
- kfree(req->rl_sendbuf);
- out2:
- kfree(req);
- out1:
- return NULL;
- }
- /**
- * rpcrdma_req_setup - Per-connection instance setup of an rpcrdma_req object
- * @r_xprt: controlling transport instance
- * @req: rpcrdma_req object to set up
- *
- * Returns zero on success, and a negative errno on failure.
- */
- int rpcrdma_req_setup(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
- {
- struct rpcrdma_regbuf *rb;
- size_t maxhdrsize;
- /* Compute maximum header buffer size in bytes */
- maxhdrsize = rpcrdma_fixed_maxsz + 3 +
- r_xprt->rx_ep->re_max_rdma_segs * rpcrdma_readchunk_maxsz;
- maxhdrsize *= sizeof(__be32);
- rb = rpcrdma_regbuf_alloc(__roundup_pow_of_two(maxhdrsize),
- DMA_TO_DEVICE, GFP_KERNEL);
- if (!rb)
- goto out;
- if (!__rpcrdma_regbuf_dma_map(r_xprt, rb))
- goto out_free;
- req->rl_rdmabuf = rb;
- xdr_buf_init(&req->rl_hdrbuf, rdmab_data(rb), rdmab_length(rb));
- return 0;
- out_free:
- rpcrdma_regbuf_free(rb);
- out:
- return -ENOMEM;
- }
- /* ASSUMPTION: the rb_allreqs list is stable for the duration,
- * and thus can be walked without holding rb_lock. Eg. the
- * caller is holding the transport send lock to exclude
- * device removal or disconnection.
- */
- static int rpcrdma_reqs_setup(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_req *req;
- int rc;
- list_for_each_entry(req, &buf->rb_allreqs, rl_all) {
- rc = rpcrdma_req_setup(r_xprt, req);
- if (rc)
- return rc;
- }
- return 0;
- }
- static void rpcrdma_req_reset(struct rpcrdma_req *req)
- {
- /* Credits are valid for only one connection */
- req->rl_slot.rq_cong = 0;
- rpcrdma_regbuf_free(req->rl_rdmabuf);
- req->rl_rdmabuf = NULL;
- rpcrdma_regbuf_dma_unmap(req->rl_sendbuf);
- rpcrdma_regbuf_dma_unmap(req->rl_recvbuf);
- frwr_reset(req);
- }
- /* ASSUMPTION: the rb_allreqs list is stable for the duration,
- * and thus can be walked without holding rb_lock. Eg. the
- * caller is holding the transport send lock to exclude
- * device removal or disconnection.
- */
- static void rpcrdma_reqs_reset(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_req *req;
- list_for_each_entry(req, &buf->rb_allreqs, rl_all)
- rpcrdma_req_reset(req);
- }
- /* No locking needed here. This function is called only by the
- * Receive completion handler.
- */
- static noinline
- struct rpcrdma_rep *rpcrdma_rep_create(struct rpcrdma_xprt *r_xprt,
- bool temp)
- {
- struct rpcrdma_rep *rep;
- rep = kzalloc(sizeof(*rep), GFP_KERNEL);
- if (rep == NULL)
- goto out;
- rep->rr_rdmabuf = rpcrdma_regbuf_alloc(r_xprt->rx_ep->re_inline_recv,
- DMA_FROM_DEVICE, GFP_KERNEL);
- if (!rep->rr_rdmabuf)
- goto out_free;
- if (!rpcrdma_regbuf_dma_map(r_xprt, rep->rr_rdmabuf))
- goto out_free_regbuf;
- xdr_buf_init(&rep->rr_hdrbuf, rdmab_data(rep->rr_rdmabuf),
- rdmab_length(rep->rr_rdmabuf));
- rep->rr_cqe.done = rpcrdma_wc_receive;
- rep->rr_rxprt = r_xprt;
- rep->rr_recv_wr.next = NULL;
- rep->rr_recv_wr.wr_cqe = &rep->rr_cqe;
- rep->rr_recv_wr.sg_list = &rep->rr_rdmabuf->rg_iov;
- rep->rr_recv_wr.num_sge = 1;
- rep->rr_temp = temp;
- list_add(&rep->rr_all, &r_xprt->rx_buf.rb_all_reps);
- return rep;
- out_free_regbuf:
- rpcrdma_regbuf_free(rep->rr_rdmabuf);
- out_free:
- kfree(rep);
- out:
- return NULL;
- }
- /* No locking needed here. This function is invoked only by the
- * Receive completion handler, or during transport shutdown.
- */
- static void rpcrdma_rep_destroy(struct rpcrdma_rep *rep)
- {
- list_del(&rep->rr_all);
- rpcrdma_regbuf_free(rep->rr_rdmabuf);
- kfree(rep);
- }
- static struct rpcrdma_rep *rpcrdma_rep_get_locked(struct rpcrdma_buffer *buf)
- {
- struct llist_node *node;
- /* Calls to llist_del_first are required to be serialized */
- node = llist_del_first(&buf->rb_free_reps);
- if (!node)
- return NULL;
- return llist_entry(node, struct rpcrdma_rep, rr_node);
- }
- static void rpcrdma_rep_put(struct rpcrdma_buffer *buf,
- struct rpcrdma_rep *rep)
- {
- llist_add(&rep->rr_node, &buf->rb_free_reps);
- }
- static void rpcrdma_reps_unmap(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_rep *rep;
- list_for_each_entry(rep, &buf->rb_all_reps, rr_all) {
- rpcrdma_regbuf_dma_unmap(rep->rr_rdmabuf);
- rep->rr_temp = true;
- }
- }
- static void rpcrdma_reps_destroy(struct rpcrdma_buffer *buf)
- {
- struct rpcrdma_rep *rep;
- while ((rep = rpcrdma_rep_get_locked(buf)) != NULL)
- rpcrdma_rep_destroy(rep);
- }
- /**
- * rpcrdma_buffer_create - Create initial set of req/rep objects
- * @r_xprt: transport instance to (re)initialize
- *
- * Returns zero on success, otherwise a negative errno.
- */
- int rpcrdma_buffer_create(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- int i, rc;
- buf->rb_bc_srv_max_requests = 0;
- spin_lock_init(&buf->rb_lock);
- INIT_LIST_HEAD(&buf->rb_mrs);
- INIT_LIST_HEAD(&buf->rb_all_mrs);
- INIT_WORK(&buf->rb_refresh_worker, rpcrdma_mr_refresh_worker);
- INIT_LIST_HEAD(&buf->rb_send_bufs);
- INIT_LIST_HEAD(&buf->rb_allreqs);
- INIT_LIST_HEAD(&buf->rb_all_reps);
- rc = -ENOMEM;
- for (i = 0; i < r_xprt->rx_xprt.max_reqs; i++) {
- struct rpcrdma_req *req;
- req = rpcrdma_req_create(r_xprt, RPCRDMA_V1_DEF_INLINE_SIZE * 2,
- GFP_KERNEL);
- if (!req)
- goto out;
- list_add(&req->rl_list, &buf->rb_send_bufs);
- }
- init_llist_head(&buf->rb_free_reps);
- return 0;
- out:
- rpcrdma_buffer_destroy(buf);
- return rc;
- }
- /**
- * rpcrdma_req_destroy - Destroy an rpcrdma_req object
- * @req: unused object to be destroyed
- *
- * Relies on caller holding the transport send lock to protect
- * removing req->rl_all from buf->rb_all_reqs safely.
- */
- void rpcrdma_req_destroy(struct rpcrdma_req *req)
- {
- struct rpcrdma_mr *mr;
- list_del(&req->rl_all);
- while ((mr = rpcrdma_mr_pop(&req->rl_free_mrs))) {
- struct rpcrdma_buffer *buf = &mr->mr_xprt->rx_buf;
- spin_lock(&buf->rb_lock);
- list_del(&mr->mr_all);
- spin_unlock(&buf->rb_lock);
- frwr_release_mr(mr);
- }
- rpcrdma_regbuf_free(req->rl_recvbuf);
- rpcrdma_regbuf_free(req->rl_sendbuf);
- rpcrdma_regbuf_free(req->rl_rdmabuf);
- kfree(req);
- }
- /**
- * rpcrdma_mrs_destroy - Release all of a transport's MRs
- * @r_xprt: controlling transport instance
- *
- * Relies on caller holding the transport send lock to protect
- * removing mr->mr_list from req->rl_free_mrs safely.
- */
- static void rpcrdma_mrs_destroy(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_mr *mr;
- cancel_work_sync(&buf->rb_refresh_worker);
- spin_lock(&buf->rb_lock);
- while ((mr = list_first_entry_or_null(&buf->rb_all_mrs,
- struct rpcrdma_mr,
- mr_all)) != NULL) {
- list_del(&mr->mr_list);
- list_del(&mr->mr_all);
- spin_unlock(&buf->rb_lock);
- frwr_release_mr(mr);
- spin_lock(&buf->rb_lock);
- }
- spin_unlock(&buf->rb_lock);
- }
- /**
- * rpcrdma_buffer_destroy - Release all hw resources
- * @buf: root control block for resources
- *
- * ORDERING: relies on a prior rpcrdma_xprt_drain :
- * - No more Send or Receive completions can occur
- * - All MRs, reps, and reqs are returned to their free lists
- */
- void
- rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf)
- {
- rpcrdma_reps_destroy(buf);
- while (!list_empty(&buf->rb_send_bufs)) {
- struct rpcrdma_req *req;
- req = list_first_entry(&buf->rb_send_bufs,
- struct rpcrdma_req, rl_list);
- list_del(&req->rl_list);
- rpcrdma_req_destroy(req);
- }
- }
- /**
- * rpcrdma_mr_get - Allocate an rpcrdma_mr object
- * @r_xprt: controlling transport
- *
- * Returns an initialized rpcrdma_mr or NULL if no free
- * rpcrdma_mr objects are available.
- */
- struct rpcrdma_mr *
- rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_mr *mr;
- spin_lock(&buf->rb_lock);
- mr = rpcrdma_mr_pop(&buf->rb_mrs);
- spin_unlock(&buf->rb_lock);
- return mr;
- }
- /**
- * rpcrdma_mr_put - DMA unmap an MR and release it
- * @mr: MR to release
- *
- */
- void rpcrdma_mr_put(struct rpcrdma_mr *mr)
- {
- struct rpcrdma_xprt *r_xprt = mr->mr_xprt;
- if (mr->mr_dir != DMA_NONE) {
- trace_xprtrdma_mr_unmap(mr);
- ib_dma_unmap_sg(r_xprt->rx_ep->re_id->device,
- mr->mr_sg, mr->mr_nents, mr->mr_dir);
- mr->mr_dir = DMA_NONE;
- }
- rpcrdma_mr_push(mr, &mr->mr_req->rl_free_mrs);
- }
- /**
- * rpcrdma_reply_put - Put reply buffers back into pool
- * @buffers: buffer pool
- * @req: object to return
- *
- */
- void rpcrdma_reply_put(struct rpcrdma_buffer *buffers, struct rpcrdma_req *req)
- {
- if (req->rl_reply) {
- rpcrdma_rep_put(buffers, req->rl_reply);
- req->rl_reply = NULL;
- }
- }
- /**
- * rpcrdma_buffer_get - Get a request buffer
- * @buffers: Buffer pool from which to obtain a buffer
- *
- * Returns a fresh rpcrdma_req, or NULL if none are available.
- */
- struct rpcrdma_req *
- rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
- {
- struct rpcrdma_req *req;
- spin_lock(&buffers->rb_lock);
- req = list_first_entry_or_null(&buffers->rb_send_bufs,
- struct rpcrdma_req, rl_list);
- if (req)
- list_del_init(&req->rl_list);
- spin_unlock(&buffers->rb_lock);
- return req;
- }
- /**
- * rpcrdma_buffer_put - Put request/reply buffers back into pool
- * @buffers: buffer pool
- * @req: object to return
- *
- */
- void rpcrdma_buffer_put(struct rpcrdma_buffer *buffers, struct rpcrdma_req *req)
- {
- rpcrdma_reply_put(buffers, req);
- spin_lock(&buffers->rb_lock);
- list_add(&req->rl_list, &buffers->rb_send_bufs);
- spin_unlock(&buffers->rb_lock);
- }
- /**
- * rpcrdma_recv_buffer_put - Release rpcrdma_rep back to free list
- * @rep: rep to release
- *
- * Used after error conditions.
- */
- void rpcrdma_recv_buffer_put(struct rpcrdma_rep *rep)
- {
- rpcrdma_rep_put(&rep->rr_rxprt->rx_buf, rep);
- }
- /* Returns a pointer to a rpcrdma_regbuf object, or NULL.
- *
- * xprtrdma uses a regbuf for posting an outgoing RDMA SEND, or for
- * receiving the payload of RDMA RECV operations. During Long Calls
- * or Replies they may be registered externally via frwr_map.
- */
- static struct rpcrdma_regbuf *
- rpcrdma_regbuf_alloc(size_t size, enum dma_data_direction direction,
- gfp_t flags)
- {
- struct rpcrdma_regbuf *rb;
- rb = kmalloc(sizeof(*rb), flags);
- if (!rb)
- return NULL;
- rb->rg_data = kmalloc(size, flags);
- if (!rb->rg_data) {
- kfree(rb);
- return NULL;
- }
- rb->rg_device = NULL;
- rb->rg_direction = direction;
- rb->rg_iov.length = size;
- return rb;
- }
- /**
- * rpcrdma_regbuf_realloc - re-allocate a SEND/RECV buffer
- * @rb: regbuf to reallocate
- * @size: size of buffer to be allocated, in bytes
- * @flags: GFP flags
- *
- * Returns true if reallocation was successful. If false is
- * returned, @rb is left untouched.
- */
- bool rpcrdma_regbuf_realloc(struct rpcrdma_regbuf *rb, size_t size, gfp_t flags)
- {
- void *buf;
- buf = kmalloc(size, flags);
- if (!buf)
- return false;
- rpcrdma_regbuf_dma_unmap(rb);
- kfree(rb->rg_data);
- rb->rg_data = buf;
- rb->rg_iov.length = size;
- return true;
- }
- /**
- * __rpcrdma_regbuf_dma_map - DMA-map a regbuf
- * @r_xprt: controlling transport instance
- * @rb: regbuf to be mapped
- *
- * Returns true if the buffer is now DMA mapped to @r_xprt's device
- */
- bool __rpcrdma_regbuf_dma_map(struct rpcrdma_xprt *r_xprt,
- struct rpcrdma_regbuf *rb)
- {
- struct ib_device *device = r_xprt->rx_ep->re_id->device;
- if (rb->rg_direction == DMA_NONE)
- return false;
- rb->rg_iov.addr = ib_dma_map_single(device, rdmab_data(rb),
- rdmab_length(rb), rb->rg_direction);
- if (ib_dma_mapping_error(device, rdmab_addr(rb))) {
- trace_xprtrdma_dma_maperr(rdmab_addr(rb));
- return false;
- }
- rb->rg_device = device;
- rb->rg_iov.lkey = r_xprt->rx_ep->re_pd->local_dma_lkey;
- return true;
- }
- static void rpcrdma_regbuf_dma_unmap(struct rpcrdma_regbuf *rb)
- {
- if (!rb)
- return;
- if (!rpcrdma_regbuf_is_mapped(rb))
- return;
- ib_dma_unmap_single(rb->rg_device, rdmab_addr(rb), rdmab_length(rb),
- rb->rg_direction);
- rb->rg_device = NULL;
- }
- static void rpcrdma_regbuf_free(struct rpcrdma_regbuf *rb)
- {
- rpcrdma_regbuf_dma_unmap(rb);
- if (rb)
- kfree(rb->rg_data);
- kfree(rb);
- }
- /**
- * rpcrdma_post_sends - Post WRs to a transport's Send Queue
- * @r_xprt: controlling transport instance
- * @req: rpcrdma_req containing the Send WR to post
- *
- * Returns 0 if the post was successful, otherwise -ENOTCONN
- * is returned.
- */
- int rpcrdma_post_sends(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
- {
- struct ib_send_wr *send_wr = &req->rl_wr;
- struct rpcrdma_ep *ep = r_xprt->rx_ep;
- int rc;
- if (!ep->re_send_count || kref_read(&req->rl_kref) > 1) {
- send_wr->send_flags |= IB_SEND_SIGNALED;
- ep->re_send_count = ep->re_send_batch;
- } else {
- send_wr->send_flags &= ~IB_SEND_SIGNALED;
- --ep->re_send_count;
- }
- trace_xprtrdma_post_send(req);
- rc = frwr_send(r_xprt, req);
- if (rc)
- return -ENOTCONN;
- return 0;
- }
- /**
- * rpcrdma_post_recvs - Refill the Receive Queue
- * @r_xprt: controlling transport instance
- * @needed: current credit grant
- * @temp: mark Receive buffers to be deleted after one use
- *
- */
- void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, int needed, bool temp)
- {
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_ep *ep = r_xprt->rx_ep;
- struct ib_recv_wr *wr, *bad_wr;
- struct rpcrdma_rep *rep;
- int count, rc;
- rc = 0;
- count = 0;
- if (likely(ep->re_receive_count > needed))
- goto out;
- needed -= ep->re_receive_count;
- if (!temp)
- needed += RPCRDMA_MAX_RECV_BATCH;
- /* fast path: all needed reps can be found on the free list */
- wr = NULL;
- while (needed) {
- rep = rpcrdma_rep_get_locked(buf);
- if (rep && rep->rr_temp) {
- rpcrdma_rep_destroy(rep);
- continue;
- }
- if (!rep)
- rep = rpcrdma_rep_create(r_xprt, temp);
- if (!rep)
- break;
- trace_xprtrdma_post_recv(rep);
- rep->rr_recv_wr.next = wr;
- wr = &rep->rr_recv_wr;
- --needed;
- ++count;
- }
- if (!wr)
- goto out;
- rc = ib_post_recv(ep->re_id->qp, wr,
- (const struct ib_recv_wr **)&bad_wr);
- out:
- trace_xprtrdma_post_recvs(r_xprt, count, rc);
- if (rc) {
- for (wr = bad_wr; wr;) {
- struct rpcrdma_rep *rep;
- rep = container_of(wr, struct rpcrdma_rep, rr_recv_wr);
- wr = wr->next;
- rpcrdma_recv_buffer_put(rep);
- --count;
- }
- }
- ep->re_receive_count += count;
- return;
- }
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