diff options
Diffstat (limited to 'net/sunrpc')
| -rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_transport.c | 1080 |
1 files changed, 1080 insertions, 0 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c new file mode 100644 index 0000000..f09444c --- /dev/null +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -0,0 +1,1080 @@ +/* + * Copyright (c) 2005-2007 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. + * + * Author: Tom Tucker <tom@opengridcomputing.com> + */ + +#include <linux/sunrpc/svc_xprt.h> +#include <linux/sunrpc/debug.h> +#include <linux/sunrpc/rpc_rdma.h> +#include <linux/spinlock.h> +#include <rdma/ib_verbs.h> +#include <rdma/rdma_cm.h> +#include <linux/sunrpc/svc_rdma.h> + +#define RPCDBG_FACILITY RPCDBG_SVCXPRT + +static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, + struct sockaddr *sa, int salen, + 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); +static int svc_rdma_has_wspace(struct svc_xprt *xprt); +static void rq_cq_reap(struct svcxprt_rdma *xprt); +static void sq_cq_reap(struct svcxprt_rdma *xprt); + +DECLARE_TASKLET(dto_tasklet, dto_tasklet_func, 0UL); +static DEFINE_SPINLOCK(dto_lock); +static LIST_HEAD(dto_xprt_q); + +static struct svc_xprt_ops svc_rdma_ops = { + .xpo_create = svc_rdma_create, + .xpo_recvfrom = svc_rdma_recvfrom, + .xpo_sendto = svc_rdma_sendto, + .xpo_release_rqst = svc_rdma_release_rqst, + .xpo_detach = svc_rdma_detach, + .xpo_free = svc_rdma_free, + .xpo_prep_reply_hdr = svc_rdma_prep_reply_hdr, + .xpo_has_wspace = svc_rdma_has_wspace, + .xpo_accept = svc_rdma_accept, +}; + +struct svc_xprt_class svc_rdma_class = { + .xcl_name = "rdma", + .xcl_owner = THIS_MODULE, + .xcl_ops = &svc_rdma_ops, + .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP, +}; + +static int rdma_bump_context_cache(struct svcxprt_rdma *xprt) +{ + int target; + int at_least_one = 0; + struct svc_rdma_op_ctxt *ctxt; + + target = min(xprt->sc_ctxt_cnt + xprt->sc_ctxt_bump, + xprt->sc_ctxt_max); + + spin_lock_bh(&xprt->sc_ctxt_lock); + while (xprt->sc_ctxt_cnt < target) { + xprt->sc_ctxt_cnt++; + spin_unlock_bh(&xprt->sc_ctxt_lock); + + ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL); + + spin_lock_bh(&xprt->sc_ctxt_lock); + if (ctxt) { + at_least_one = 1; + ctxt->next = xprt->sc_ctxt_head; + xprt->sc_ctxt_head = ctxt; + } else { + /* kmalloc failed...give up for now */ + xprt->sc_ctxt_cnt--; + break; + } + } + spin_unlock_bh(&xprt->sc_ctxt_lock); + dprintk("svcrdma: sc_ctxt_max=%d, sc_ctxt_cnt=%d\n", + xprt->sc_ctxt_max, xprt->sc_ctxt_cnt); + return at_least_one; +} + +struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt) +{ + struct svc_rdma_op_ctxt *ctxt; + + while (1) { + spin_lock_bh(&xprt->sc_ctxt_lock); + if (unlikely(xprt->sc_ctxt_head == NULL)) { + /* Try to bump my cache. */ + spin_unlock_bh(&xprt->sc_ctxt_lock); + + if (rdma_bump_context_cache(xprt)) + continue; + + printk(KERN_INFO "svcrdma: sleeping waiting for " + "context memory on xprt=%p\n", + xprt); + schedule_timeout_uninterruptible(msecs_to_jiffies(500)); + continue; + } + ctxt = xprt->sc_ctxt_head; + xprt->sc_ctxt_head = ctxt->next; + spin_unlock_bh(&xprt->sc_ctxt_lock); + ctxt->xprt = xprt; + INIT_LIST_HEAD(&ctxt->dto_q); + ctxt->count = 0; + break; + } + return ctxt; +} + +void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages) +{ + struct svcxprt_rdma *xprt; + int i; + + BUG_ON(!ctxt); + xprt = ctxt->xprt; + if (free_pages) + for (i = 0; i < ctxt->count; i++) + put_page(ctxt->pages[i]); + + for (i = 0; i < ctxt->count; i++) + dma_unmap_single(xprt->sc_cm_id->device->dma_device, + ctxt->sge[i].addr, + ctxt->sge[i].length, + ctxt->direction); + spin_lock_bh(&xprt->sc_ctxt_lock); + ctxt->next = xprt->sc_ctxt_head; + xprt->sc_ctxt_head = ctxt; + spin_unlock_bh(&xprt->sc_ctxt_lock); +} + +/* ib_cq event handler */ +static void cq_event_handler(struct ib_event *event, void *context) +{ + struct svc_xprt *xprt = context; + dprintk("svcrdma: received CQ event id=%d, context=%p\n", + event->event, context); + set_bit(XPT_CLOSE, &xprt->xpt_flags); +} + +/* QP event handler */ +static void qp_event_handler(struct ib_event *event, void *context) +{ + struct svc_xprt *xprt = context; + + switch (event->event) { + /* These are considered benign events */ + case IB_EVENT_PATH_MIG: + case IB_EVENT_COMM_EST: + case IB_EVENT_SQ_DRAINED: + case IB_EVENT_QP_LAST_WQE_REACHED: + dprintk("svcrdma: QP event %d received for QP=%p\n", + event->event, event->element.qp); + break; + /* These are considered fatal events */ + case IB_EVENT_PATH_MIG_ERR: + case IB_EVENT_QP_FATAL: + case IB_EVENT_QP_REQ_ERR: + case IB_EVENT_QP_ACCESS_ERR: + case IB_EVENT_DEVICE_FATAL: + default: + dprintk("svcrdma: QP ERROR event %d received for QP=%p, " + "closing transport\n", + event->event, event->element.qp); + set_bit(XPT_CLOSE, &xprt->xpt_flags); + break; + } +} + +/* + * Data Transfer Operation Tasklet + * + * Walks a list of transports with I/O pending, removing entries as + * they are added to the server's I/O pending list. Two bits indicate + * if SQ, RQ, or both have I/O pending. The dto_lock is an irqsave + * spinlock that serializes access to the transport list with the RQ + * and SQ interrupt handlers. + */ +static void dto_tasklet_func(unsigned long data) +{ + struct svcxprt_rdma *xprt; + unsigned long flags; + + spin_lock_irqsave(&dto_lock, flags); + while (!list_empty(&dto_xprt_q)) { + xprt = list_entry(dto_xprt_q.next, + struct svcxprt_rdma, sc_dto_q); + list_del_init(&xprt->sc_dto_q); + spin_unlock_irqrestore(&dto_lock, flags); + + if (test_and_clear_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags)) { + ib_req_notify_cq(xprt->sc_rq_cq, IB_CQ_NEXT_COMP); + rq_cq_reap(xprt); + set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags); + /* + * If data arrived before established event, + * don't enqueue. This defers RPC I/O until the + * RDMA connection is complete. + */ + if (!test_bit(RDMAXPRT_CONN_PENDING, &xprt->sc_flags)) + svc_xprt_enqueue(&xprt->sc_xprt); + } + + if (test_and_clear_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags)) { + ib_req_notify_cq(xprt->sc_sq_cq, IB_CQ_NEXT_COMP); + sq_cq_reap(xprt); + } + + spin_lock_irqsave(&dto_lock, flags); + } + spin_unlock_irqrestore(&dto_lock, flags); +} + +/* + * Receive Queue Completion Handler + * + * Since an RQ completion handler is called on interrupt context, we + * need to defer the handling of the I/O to a tasklet + */ +static void rq_comp_handler(struct ib_cq *cq, void *cq_context) +{ + struct svcxprt_rdma *xprt = cq_context; + unsigned long flags; + + /* + * Set the bit regardless of whether or not it's on the list + * because it may be on the list already due to an SQ + * completion. + */ + set_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags); + + /* + * If this transport is not already on the DTO transport queue, + * add it + */ + spin_lock_irqsave(&dto_lock, flags); + if (list_empty(&xprt->sc_dto_q)) + 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. */ + tasklet_schedule(&dto_tasklet); +} + +/* + * rq_cq_reap - Process the RQ CQ. + * + * Take all completing WC off the CQE and enqueue the associated DTO + * context on the dto_q for the transport. + */ +static void rq_cq_reap(struct svcxprt_rdma *xprt) +{ + int ret; + struct ib_wc wc; + struct svc_rdma_op_ctxt *ctxt = NULL; + + atomic_inc(&rdma_stat_rq_poll); + + spin_lock_bh(&xprt->sc_rq_dto_lock); + while ((ret = ib_poll_cq(xprt->sc_rq_cq, 1, &wc)) > 0) { + ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id; + ctxt->wc_status = wc.status; + ctxt->byte_len = wc.byte_len; + if (wc.status != IB_WC_SUCCESS) { + /* Close the transport */ + set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); + svc_rdma_put_context(ctxt, 1); + continue; + } + list_add_tail(&ctxt->dto_q, &xprt->sc_rq_dto_q); + } + spin_unlock_bh(&xprt->sc_rq_dto_lock); + + if (ctxt) + atomic_inc(&rdma_stat_rq_prod); +} + +/* + * Send Queue Completion Handler - potentially called on interrupt context. + */ +static void sq_cq_reap(struct svcxprt_rdma *xprt) +{ + struct svc_rdma_op_ctxt *ctxt = NULL; + struct ib_wc wc; + struct ib_cq *cq = xprt->sc_sq_cq; + int ret; + + atomic_inc(&rdma_stat_sq_poll); + while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) { + ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id; + xprt = ctxt->xprt; + + if (wc.status != IB_WC_SUCCESS) + /* Close the transport */ + set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); + + /* Decrement used SQ WR count */ + atomic_dec(&xprt->sc_sq_count); + wake_up(&xprt->sc_send_wait); + + switch (ctxt->wr_op) { + case IB_WR_SEND: + case IB_WR_RDMA_WRITE: + svc_rdma_put_context(ctxt, 1); + break; + + case IB_WR_RDMA_READ: + if (test_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags)) { + set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags); + set_bit(RDMACTXT_F_READ_DONE, &ctxt->flags); + spin_lock_bh(&xprt->sc_read_complete_lock); + list_add_tail(&ctxt->dto_q, + &xprt->sc_read_complete_q); + spin_unlock_bh(&xprt->sc_read_complete_lock); + svc_xprt_enqueue(&xprt->sc_xprt); + } + break; + + default: + printk(KERN_ERR "svcrdma: unexpected completion type, " + "opcode=%d, status=%d\n", + wc.opcode, wc.status); + break; + } + } + + if (ctxt) + atomic_inc(&rdma_stat_sq_prod); +} + +static void sq_comp_handler(struct ib_cq *cq, void *cq_context) +{ + struct svcxprt_rdma *xprt = cq_context; + unsigned long flags; + + /* + * Set the bit regardless of whether or not it's on the list + * because it may be on the list already due to an RQ + * completion. + */ + set_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags); + + /* + * If this transport is not already on the DTO transport queue, + * add it + */ + spin_lock_irqsave(&dto_lock, flags); + if (list_empty(&xprt->sc_dto_q)) + 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. */ + tasklet_schedule(&dto_tasklet); +} + +static void create_context_cache(struct svcxprt_rdma *xprt, + int ctxt_count, int ctxt_bump, int ctxt_max) +{ + struct svc_rdma_op_ctxt *ctxt; + int i; + + xprt->sc_ctxt_max = ctxt_max; + xprt->sc_ctxt_bump = ctxt_bump; + xprt->sc_ctxt_cnt = 0; + xprt->sc_ctxt_head = NULL; + for (i = 0; i < ctxt_count; i++) { + ctxt = kmalloc(sizeof(*ctxt), GFP_KERNEL); + if (ctxt) { + ctxt->next = xprt->sc_ctxt_head; + xprt->sc_ctxt_head = ctxt; + xprt->sc_ctxt_cnt++; + } + } +} + +static void destroy_context_cache(struct svc_rdma_op_ctxt *ctxt) +{ + struct svc_rdma_op_ctxt *next; + if (!ctxt) + return; + + do { + next = ctxt->next; + kfree(ctxt); + ctxt = next; + } while (next); +} + +static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv, + int listener) +{ + struct svcxprt_rdma *cma_xprt = kzalloc(sizeof *cma_xprt, GFP_KERNEL); + + if (!cma_xprt) + return NULL; + svc_xprt_init(&svc_rdma_class, &cma_xprt->sc_xprt, serv); + INIT_LIST_HEAD(&cma_xprt->sc_accept_q); + INIT_LIST_HEAD(&cma_xprt->sc_dto_q); + INIT_LIST_HEAD(&cma_xprt->sc_rq_dto_q); + INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q); + init_waitqueue_head(&cma_xprt->sc_send_wait); + + spin_lock_init(&cma_xprt->sc_lock); + spin_lock_init(&cma_xprt->sc_read_complete_lock); + spin_lock_init(&cma_xprt->sc_ctxt_lock); + spin_lock_init(&cma_xprt->sc_rq_dto_lock); + + cma_xprt->sc_ord = svcrdma_ord; + + cma_xprt->sc_max_req_size = svcrdma_max_req_size; + cma_xprt->sc_max_requests = svcrdma_max_requests; + cma_xprt->sc_sq_depth = svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT; + atomic_set(&cma_xprt->sc_sq_count, 0); + + if (!listener) { + int reqs = cma_xprt->sc_max_requests; + create_context_cache(cma_xprt, + reqs << 1, /* starting size */ + reqs, /* bump amount */ + reqs + + cma_xprt->sc_sq_depth + + RPCRDMA_MAX_THREADS + 1); /* max */ + if (!cma_xprt->sc_ctxt_head) { + kfree(cma_xprt); + return NULL; + } + clear_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags); + } else + set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags); + + return cma_xprt; +} + +struct page *svc_rdma_get_page(void) +{ + struct page *page; + + while ((page = alloc_page(GFP_KERNEL)) == NULL) { + /* If we can't get memory, wait a bit and try again */ + printk(KERN_INFO "svcrdma: out of memory...retrying in 1000 " + "jiffies.\n"); + schedule_timeout_uninterruptible(msecs_to_jiffies(1000)); + } + return page; +} + +int svc_rdma_post_recv(struct svcxprt_rdma *xprt) +{ + struct ib_recv_wr recv_wr, *bad_recv_wr; + struct svc_rdma_op_ctxt *ctxt; + struct page *page; + unsigned long pa; + int sge_no; + int buflen; + int ret; + + ctxt = svc_rdma_get_context(xprt); + buflen = 0; + ctxt->direction = DMA_FROM_DEVICE; + for (sge_no = 0; buflen < xprt->sc_max_req_size; sge_no++) { + BUG_ON(sge_no >= xprt->sc_max_sge); + page = svc_rdma_get_page(); + ctxt->pages[sge_no] = page; + pa = ib_dma_map_page(xprt->sc_cm_id->device, + page, 0, PAGE_SIZE, + DMA_FROM_DEVICE); + ctxt->sge[sge_no].addr = pa; + ctxt->sge[sge_no].length = PAGE_SIZE; + ctxt->sge[sge_no].lkey = xprt->sc_phys_mr->lkey; + buflen += PAGE_SIZE; + } + ctxt->count = sge_no; + recv_wr.next = NULL; + recv_wr.sg_list = &ctxt->sge[0]; + recv_wr.num_sge = ctxt->count; + recv_wr.wr_id = (u64)(unsigned long)ctxt; + + ret = ib_post_recv(xprt->sc_qp, &recv_wr, &bad_recv_wr); + return ret; +} + +/* + * This function handles the CONNECT_REQUEST event on a listening + * endpoint. It is passed the cma_id for the _new_ connection. The context in + * this cma_id is inherited from the listening cma_id and is the svc_xprt + * structure for the listening endpoint. + * + * This function creates a new xprt for the new connection and enqueues it on + * the accept queue for the listent xprt. When the listen thread is kicked, it + * will call the recvfrom method on the listen xprt which will accept the new + * connection. + */ +static void handle_connect_req(struct rdma_cm_id *new_cma_id) +{ + struct svcxprt_rdma *listen_xprt = new_cma_id->context; + struct svcxprt_rdma *newxprt; + + /* Create a new transport */ + newxprt = rdma_create_xprt(listen_xprt->sc_xprt.xpt_server, 0); + if (!newxprt) { + dprintk("svcrdma: failed to create new transport\n"); + return; + } + newxprt->sc_cm_id = new_cma_id; + new_cma_id->context = newxprt; + dprintk("svcrdma: Creating newxprt=%p, cm_id=%p, listenxprt=%p\n", + newxprt, newxprt->sc_cm_id, listen_xprt); + + /* + * Enqueue the new transport on the accept queue of the listening + * transport + */ + spin_lock_bh(&listen_xprt->sc_lock); + list_add_tail(&newxprt->sc_accept_q, &listen_xprt->sc_accept_q); + spin_unlock_bh(&listen_xprt->sc_lock); + + /* + * Can't use svc_xprt_received here because we are not on a + * rqstp thread + */ + set_bit(XPT_CONN, &listen_xprt->sc_xprt.xpt_flags); + svc_xprt_enqueue(&listen_xprt->sc_xprt); +} + +/* + * Handles events generated on the listening endpoint. These events will be + * either be incoming connect requests or adapter removal events. + */ +static int rdma_listen_handler(struct rdma_cm_id *cma_id, + struct rdma_cm_event *event) +{ + struct svcxprt_rdma *xprt = cma_id->context; + int ret = 0; + + switch (event->event) { + case RDMA_CM_EVENT_CONNECT_REQUEST: + dprintk("svcrdma: Connect request on cma_id=%p, xprt = %p, " + "event=%d\n", cma_id, cma_id->context, event->event); + handle_connect_req(cma_id); + break; + + case RDMA_CM_EVENT_ESTABLISHED: + /* Accept complete */ + dprintk("svcrdma: Connection completed on LISTEN xprt=%p, " + "cm_id=%p\n", xprt, cma_id); + break; + + case RDMA_CM_EVENT_DEVICE_REMOVAL: + dprintk("svcrdma: Device removal xprt=%p, cm_id=%p\n", + xprt, cma_id); + if (xprt) + set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); + break; + + default: + dprintk("svcrdma: Unexpected event on listening endpoint %p, " + "event=%d\n", cma_id, event->event); + break; + } + + return ret; +} + +static int rdma_cma_handler(struct rdma_cm_id *cma_id, + struct rdma_cm_event *event) +{ + struct svc_xprt *xprt = cma_id->context; + struct svcxprt_rdma *rdma = + container_of(xprt, struct svcxprt_rdma, sc_xprt); + switch (event->event) { + case RDMA_CM_EVENT_ESTABLISHED: + /* Accept complete */ + dprintk("svcrdma: Connection completed on DTO xprt=%p, " + "cm_id=%p\n", xprt, cma_id); + clear_bit(RDMAXPRT_CONN_PENDING, &rdma->sc_flags); + svc_xprt_enqueue(xprt); + break; + case RDMA_CM_EVENT_DISCONNECTED: + dprintk("svcrdma: Disconnect on DTO xprt=%p, cm_id=%p\n", + xprt, cma_id); + if (xprt) { + set_bit(XPT_CLOSE, &xprt->xpt_flags); + svc_xprt_enqueue(xprt); + } + break; + case RDMA_CM_EVENT_DEVICE_REMOVAL: + dprintk("svcrdma: Device removal cma_id=%p, xprt = %p, " + "event=%d\n", cma_id, xprt, event->event); + if (xprt) { + set_bit(XPT_CLOSE, &xprt->xpt_flags); + svc_xprt_enqueue(xprt); + } + break; + default: + dprintk("svcrdma: Unexpected event on DTO endpoint %p, " + "event=%d\n", cma_id, event->event); + break; + } + return 0; +} + +/* + * Create a listening RDMA service endpoint. + */ +static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, + struct sockaddr *sa, int salen, + int flags) +{ + struct rdma_cm_id *listen_id; + struct svcxprt_rdma *cma_xprt; + struct svc_xprt *xprt; + int ret; + + dprintk("svcrdma: Creating RDMA socket\n"); + + cma_xprt = rdma_create_xprt(serv, 1); + if (!cma_xprt) + return ERR_PTR(ENOMEM); + xprt = &cma_xprt->sc_xprt; + + listen_id = rdma_create_id(rdma_listen_handler, cma_xprt, RDMA_PS_TCP); + if (IS_ERR(listen_id)) { + rdma_destroy_xprt(cma_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); + dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret); + return ERR_PTR(ret); + } + cma_xprt->sc_cm_id = listen_id; + + ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG); + if (ret) { + rdma_destroy_id(listen_id); + rdma_destroy_xprt(cma_xprt); + dprintk("svcrdma: rdma_listen failed = %d\n", ret); + } + + /* + * We need to use the address from the cm_id in case the + * caller specified 0 for the port number. + */ + sa = (struct sockaddr *)&cma_xprt->sc_cm_id->route.addr.src_addr; + svc_xprt_set_local(&cma_xprt->sc_xprt, sa, salen); + + return &cma_xprt->sc_xprt; +} + +/* + * This is the xpo_recvfrom function for listening endpoints. Its + * purpose is to accept incoming connections. The CMA callback handler + * has already created a new transport and attached it to the new CMA + * ID. + * + * There is a queue of pending connections hung on the listening + * transport. This queue contains the new svc_xprt structure. This + * function takes svc_xprt structures off the accept_q and completes + * the connection. + */ +static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) +{ + struct svcxprt_rdma *listen_rdma; + struct svcxprt_rdma *newxprt = NULL; + struct rdma_conn_param conn_param; + struct ib_qp_init_attr qp_attr; + struct ib_device_attr devattr; + struct sockaddr *sa; + int ret; + int i; + + listen_rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt); + clear_bit(XPT_CONN, &xprt->xpt_flags); + /* Get the next entry off the accept list */ + spin_lock_bh(&listen_rdma->sc_lock); + if (!list_empty(&listen_rdma->sc_accept_q)) { + newxprt = list_entry(listen_rdma->sc_accept_q.next, + struct svcxprt_rdma, sc_accept_q); + list_del_init(&newxprt->sc_accept_q); + } + if (!list_empty(&listen_rdma->sc_accept_q)) + set_bit(XPT_CONN, &listen_rdma->sc_xprt.xpt_flags); + spin_unlock_bh(&listen_rdma->sc_lock); + if (!newxprt) + return NULL; + + dprintk("svcrdma: newxprt from accept queue = %p, cm_id=%p\n", + newxprt, newxprt->sc_cm_id); + + ret = ib_query_device(newxprt->sc_cm_id->device, &devattr); + if (ret) { + dprintk("svcrdma: could not query device attributes on " + "device %p, rc=%d\n", newxprt->sc_cm_id->device, ret); + goto errout; + } + + /* Qualify the transport resource defaults with the + * capabilities of this particular device */ + newxprt->sc_max_sge = min((size_t)devattr.max_sge, + (size_t)RPCSVC_MAXPAGES); + newxprt->sc_max_requests = min((size_t)devattr.max_qp_wr, + (size_t)svcrdma_max_requests); + newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests; + + newxprt->sc_ord = min((size_t)devattr.max_qp_rd_atom, + (size_t)svcrdma_ord); + + newxprt->sc_pd = ib_alloc_pd(newxprt->sc_cm_id->device); + if (IS_ERR(newxprt->sc_pd)) { + dprintk("svcrdma: error creating PD for connect request\n"); + goto errout; + } + newxprt->sc_sq_cq = ib_create_cq(newxprt->sc_cm_id->device, + sq_comp_handler, + cq_event_handler, + newxprt, + newxprt->sc_sq_depth, + 0); + if (IS_ERR(newxprt->sc_sq_cq)) { + dprintk("svcrdma: error creating SQ CQ for connect request\n"); + goto errout; + } + newxprt->sc_rq_cq = ib_create_cq(newxprt->sc_cm_id->device, + rq_comp_handler, + cq_event_handler, + newxprt, + newxprt->sc_max_requests, + 0); + if (IS_ERR(newxprt->sc_rq_cq)) { + dprintk("svcrdma: error creating RQ CQ for connect request\n"); + goto errout; + } + + memset(&qp_attr, 0, sizeof qp_attr); + qp_attr.event_handler = qp_event_handler; + qp_attr.qp_context = &newxprt->sc_xprt; + qp_attr.cap.max_send_wr = newxprt->sc_sq_depth; + qp_attr.cap.max_recv_wr = newxprt->sc_max_requests; + qp_attr.cap.max_send_sge = newxprt->sc_max_sge; + qp_attr.cap.max_recv_sge = newxprt->sc_max_sge; + qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; + qp_attr.qp_type = IB_QPT_RC; + qp_attr.send_cq = newxprt->sc_sq_cq; + qp_attr.recv_cq = newxprt->sc_rq_cq; + dprintk("svcrdma: newxprt->sc_cm_id=%p, newxprt->sc_pd=%p\n" + " cm_id->device=%p, sc_pd->device=%p\n" + " cap.max_send_wr = %d\n" + " cap.max_recv_wr = %d\n" + " cap.max_send_sge = %d\n" + " cap.max_recv_sge = %d\n", + newxprt->sc_cm_id, newxprt->sc_pd, + newxprt->sc_cm_id->device, newxprt->sc_pd->device, + qp_attr.cap.max_send_wr, + qp_attr.cap.max_recv_wr, + qp_attr.cap.max_send_sge, + qp_attr.cap.max_recv_sge); + + ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr); + if (ret) { + /* + * XXX: This is a hack. We need a xx_request_qp interface + * that will adjust the qp_attr's with a best-effort + * number + */ + qp_attr.cap.max_send_sge -= 2; + qp_attr.cap.max_recv_sge -= 2; + ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, + &qp_attr); + if (ret) { + dprintk("svcrdma: failed to create QP, ret=%d\n", ret); + goto errout; + } + newxprt->sc_max_sge = qp_attr.cap.max_send_sge; + newxprt->sc_max_sge = qp_attr.cap.max_recv_sge; + newxprt->sc_sq_depth = qp_attr.cap.max_send_wr; + newxprt->sc_max_requests = qp_attr.cap.max_recv_wr; + } + newxprt->sc_qp = newxprt->sc_cm_id->qp; + + /* Register all of physical memory */ + newxprt->sc_phys_mr = ib_get_dma_mr(newxprt->sc_pd, + IB_ACCESS_LOCAL_WRITE | + IB_ACCESS_REMOTE_WRITE); + if (IS_ERR(newxprt->sc_phys_mr)) { + dprintk("svcrdma: Failed to create DMA MR ret=%d\n", ret); + goto errout; + } + + /* Post receive buffers */ + for (i = 0; i < newxprt->sc_max_requests; i++) { + ret = svc_rdma_post_recv(newxprt); + if (ret) { + dprintk("svcrdma: failure posting receive buffers\n"); + goto errout; + } + } + + /* Swap out the handler */ + newxprt->sc_cm_id->event_handler = rdma_cma_handler; + + /* Accept Connection */ + set_bit(RDMAXPRT_CONN_PENDING, &newxprt->sc_flags); + memset(&conn_param, 0, sizeof conn_param); + conn_param.responder_resources = 0; + conn_param.initiator_depth = newxprt->sc_ord; + ret = rdma_accept(newxprt->sc_cm_id, &conn_param); + if (ret) { + dprintk("svcrdma: failed to accept new connection, ret=%d\n", + ret); + goto errout; + } + + dprintk("svcrdma: new connection %p accepted with the following " + "attributes:\n" + " local_ip : %d.%d.%d.%d\n" + " local_port : %d\n" + " remote_ip : %d.%d.%d.%d\n" + " remote_port : %d\n" + " max_sge : %d\n" + " sq_depth : %d\n" + " max_requests : %d\n" + " ord : %d\n", + newxprt, + NIPQUAD(((struct sockaddr_in *)&newxprt->sc_cm_id-> + route.addr.src_addr)->sin_addr.s_addr), + ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id-> + route.addr.src_addr)->sin_port), + NIPQUAD(((struct sockaddr_in *)&newxprt->sc_cm_id-> + route.addr.dst_addr)->sin_addr.s_addr), + ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id-> + route.addr.dst_addr)->sin_port), + newxprt->sc_max_sge, + newxprt->sc_sq_depth, + newxprt->sc_max_requests, + newxprt->sc_ord); + + /* Set the local and remote addresses in the transport */ + sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr; + svc_xprt_set_remote(&newxprt->sc_xprt, sa, svc_addr_len(sa)); + sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr; + svc_xprt_set_local(&newxprt->sc_xprt, sa, svc_addr_len(sa)); + + ib_req_notify_cq(newxprt->sc_sq_cq, IB_CQ_NEXT_COMP); + ib_req_notify_cq(newxprt->sc_rq_cq, IB_CQ_NEXT_COMP); + return &newxprt->sc_xprt; + + errout: + dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret); + rdma_destroy_id(newxprt->sc_cm_id); + rdma_destroy_xprt(newxprt); + return NULL; +} + +/* + * Post an RQ WQE to the RQ when the rqst is being released. This + * effectively returns an RQ credit to the client. The rq_xprt_ctxt + * will be null if the request is deferred due to an RDMA_READ or the + * transport had no data ready (EAGAIN). Note that an RPC deferred in + * svc_process will still return the credit, this is because the data + * is copied and no longer consume a WQE/WC. + */ +static void svc_rdma_release_rqst(struct svc_rqst *rqstp) +{ + int err; + struct svcxprt_rdma *rdma = + container_of(rqstp->rq_xprt, struct svcxprt_rdma, sc_xprt); + if (rqstp->rq_xprt_ctxt) { + BUG_ON(rqstp->rq_xprt_ctxt != rdma); + err = svc_rdma_post_recv(rdma); + if (err) + dprintk("svcrdma: failed to post an RQ WQE error=%d\n", + err); + } + rqstp->rq_xprt_ctxt = NULL; +} + +/* Disable data ready events for this connection */ +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. + */ + 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); +} + +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); + + if (xprt->sc_rq_cq && !IS_ERR(xprt->sc_rq_cq)) + ib_destroy_cq(xprt->sc_rq_cq); + + if (xprt->sc_phys_mr && !IS_ERR(xprt->sc_phys_mr)) + ib_dereg_mr(xprt->sc_phys_mr); + + if (xprt->sc_pd && !IS_ERR(xprt->sc_pd)) + ib_dealloc_pd(xprt->sc_pd); + + destroy_context_cache(xprt->sc_ctxt_head); +} + +static int svc_rdma_has_wspace(struct svc_xprt *xprt) +{ + struct svcxprt_rdma *rdma = + container_of(xprt, struct svcxprt_rdma, sc_xprt); + + /* + * If there are fewer SQ WR available than required to send a + * simple response, return false. + */ + if ((rdma->sc_sq_depth - atomic_read(&rdma->sc_sq_count) < 3)) + return 0; + + /* + * ...or there are already waiters on the SQ, + * return false. + */ + if (waitqueue_active(&rdma->sc_send_wait)) + return 0; + + /* Otherwise return true. */ + return 1; +} + +int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr) +{ + struct ib_send_wr *bad_wr; + int ret; + + if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags)) + return 0; + + BUG_ON(wr->send_flags != IB_SEND_SIGNALED); + BUG_ON(((struct svc_rdma_op_ctxt *)(unsigned long)wr->wr_id)->wr_op != + wr->opcode); + /* If the SQ is full, wait until an SQ entry is available */ + while (1) { + spin_lock_bh(&xprt->sc_lock); + if (xprt->sc_sq_depth == atomic_read(&xprt->sc_sq_count)) { + spin_unlock_bh(&xprt->sc_lock); + atomic_inc(&rdma_stat_sq_starve); + /* See if we can reap some SQ WR */ + sq_cq_reap(xprt); + + /* Wait until SQ WR available if SQ still full */ + wait_event(xprt->sc_send_wait, + atomic_read(&xprt->sc_sq_count) < + xprt->sc_sq_depth); + continue; + } + /* Bumped used SQ WR count and post */ + ret = ib_post_send(xprt->sc_qp, wr, &bad_wr); + if (!ret) + atomic_inc(&xprt->sc_sq_count); + else + dprintk("svcrdma: failed to post SQ WR rc=%d, " + "sc_sq_count=%d, sc_sq_depth=%d\n", + ret, atomic_read(&xprt->sc_sq_count), + xprt->sc_sq_depth); + spin_unlock_bh(&xprt->sc_lock); + break; + } + return ret; +} + +int svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp, + enum rpcrdma_errcode err) +{ + struct ib_send_wr err_wr; + struct ib_sge sge; + struct page *p; + struct svc_rdma_op_ctxt *ctxt; + u32 *va; + int length; + int ret; + + p = svc_rdma_get_page(); + va = page_address(p); + + /* XDR encode error */ + length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va); + + /* Prepare SGE for local address */ + sge.addr = ib_dma_map_page(xprt->sc_cm_id->device, + p, 0, PAGE_SIZE, DMA_FROM_DEVICE); + sge.lkey = xprt->sc_phys_mr->lkey; + sge.length = length; + + ctxt = svc_rdma_get_context(xprt); + ctxt->count = 1; + ctxt->pages[0] = p; + + /* Prepare SEND WR */ + memset(&err_wr, 0, sizeof err_wr); + ctxt->wr_op = IB_WR_SEND; + err_wr.wr_id = (unsigned long)ctxt; + err_wr.sg_list = &sge; + err_wr.num_sge = 1; + err_wr.opcode = IB_WR_SEND; + err_wr.send_flags = IB_SEND_SIGNALED; + + /* Post It */ + ret = svc_rdma_send(xprt, &err_wr); + if (ret) { + dprintk("svcrdma: Error posting send = %d\n", ret); + svc_rdma_put_context(ctxt, 1); + } + + return ret; +} |
