From: Or Gerlitz Date: Thu, 11 May 2006 07:02:46 +0000 (+0300) Subject: IB/iser: iSER RDMA CM (CMA) and IB verbs interaction X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1cfa0a75dbef1d5bf687aacafabb023288f6b36a;p=linux-beck.git IB/iser: iSER RDMA CM (CMA) and IB verbs interaction This file contains the low level interaction with the RDMA CM and the IB verbs, where iSER is consumer of both. Signed-off-by: Or Gerlitz Signed-off-by: Roland Dreier --- diff --git a/drivers/infiniband/ulp/iser/iser_verbs.c b/drivers/infiniband/ulp/iser/iser_verbs.c new file mode 100644 index 000000000000..ff117bbf81b4 --- /dev/null +++ b/drivers/infiniband/ulp/iser/iser_verbs.c @@ -0,0 +1,827 @@ +/* + * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved. + * Copyright (c) 2005, 2006 Cisco Systems. 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 + * OpenIB.org BSD 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. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * $Id: iser_verbs.c 7051 2006-05-10 12:29:11Z ogerlitz $ + */ +#include +#include +#include +#include +#include +#include + +#include "iscsi_iser.h" + +#define ISCSI_ISER_MAX_CONN 8 +#define ISER_MAX_CQ_LEN ((ISER_QP_MAX_RECV_DTOS + \ + ISER_QP_MAX_REQ_DTOS) * \ + ISCSI_ISER_MAX_CONN) + +static void iser_cq_tasklet_fn(unsigned long data); +static void iser_cq_callback(struct ib_cq *cq, void *cq_context); +static void iser_comp_error_worker(void *data); + +static void iser_cq_event_callback(struct ib_event *cause, void *context) +{ + iser_err("got cq event %d \n", cause->event); +} + +static void iser_qp_event_callback(struct ib_event *cause, void *context) +{ + iser_err("got qp event %d\n",cause->event); +} + +/** + * iser_create_device_ib_res - creates Protection Domain (PD), Completion + * Queue (CQ), DMA Memory Region (DMA MR) with the device associated with + * the adapator. + * + * returns 0 on success, -1 on failure + */ +static int iser_create_device_ib_res(struct iser_device *device) +{ + device->pd = ib_alloc_pd(device->ib_device); + if (IS_ERR(device->pd)) + goto pd_err; + + device->cq = ib_create_cq(device->ib_device, + iser_cq_callback, + iser_cq_event_callback, + (void *)device, + ISER_MAX_CQ_LEN); + if (IS_ERR(device->cq)) + goto cq_err; + + if (ib_req_notify_cq(device->cq, IB_CQ_NEXT_COMP)) + goto cq_arm_err; + + tasklet_init(&device->cq_tasklet, + iser_cq_tasklet_fn, + (unsigned long)device); + + device->mr = ib_get_dma_mr(device->pd, + IB_ACCESS_LOCAL_WRITE); + if (IS_ERR(device->mr)) + goto dma_mr_err; + + return 0; + +dma_mr_err: + tasklet_kill(&device->cq_tasklet); +cq_arm_err: + ib_destroy_cq(device->cq); +cq_err: + ib_dealloc_pd(device->pd); +pd_err: + iser_err("failed to allocate an IB resource\n"); + return -1; +} + +/** + * iser_free_device_ib_res - destory/dealloc/dereg the DMA MR, + * CQ and PD created with the device associated with the adapator. + */ +static void iser_free_device_ib_res(struct iser_device *device) +{ + BUG_ON(device->mr == NULL); + + tasklet_kill(&device->cq_tasklet); + + (void)ib_dereg_mr(device->mr); + (void)ib_destroy_cq(device->cq); + (void)ib_dealloc_pd(device->pd); + + device->mr = NULL; + device->cq = NULL; + device->pd = NULL; +} + +/** + * iser_create_ib_conn_res - Creates FMR pool and Queue-Pair (QP) + * + * returns 0 on success, -1 on failure + */ +static int iser_create_ib_conn_res(struct iser_conn *ib_conn) +{ + struct iser_device *device; + struct ib_qp_init_attr init_attr; + int ret; + struct ib_fmr_pool_param params; + + BUG_ON(ib_conn->device == NULL); + + device = ib_conn->device; + + ib_conn->page_vec = kmalloc(sizeof(struct iser_page_vec) + + (sizeof(u64) * (ISCSI_ISER_SG_TABLESIZE +1)), + GFP_KERNEL); + if (!ib_conn->page_vec) { + ret = -ENOMEM; + goto alloc_err; + } + ib_conn->page_vec->pages = (u64 *) (ib_conn->page_vec + 1); + + params.page_shift = PAGE_SHIFT; + /* when the first/last SG element are not start/end * + * page aligned, the map whould be of N+1 pages */ + params.max_pages_per_fmr = ISCSI_ISER_SG_TABLESIZE + 1; + /* make the pool size twice the max number of SCSI commands * + * the ML is expected to queue, watermark for unmap at 50% */ + params.pool_size = ISCSI_XMIT_CMDS_MAX * 2; + params.dirty_watermark = ISCSI_XMIT_CMDS_MAX; + params.cache = 0; + params.flush_function = NULL; + params.access = (IB_ACCESS_LOCAL_WRITE | + IB_ACCESS_REMOTE_WRITE | + IB_ACCESS_REMOTE_READ); + + ib_conn->fmr_pool = ib_create_fmr_pool(device->pd, ¶ms); + if (IS_ERR(ib_conn->fmr_pool)) { + ret = PTR_ERR(ib_conn->fmr_pool); + goto fmr_pool_err; + } + + memset(&init_attr, 0, sizeof init_attr); + + init_attr.event_handler = iser_qp_event_callback; + init_attr.qp_context = (void *)ib_conn; + init_attr.send_cq = device->cq; + init_attr.recv_cq = device->cq; + init_attr.cap.max_send_wr = ISER_QP_MAX_REQ_DTOS; + init_attr.cap.max_recv_wr = ISER_QP_MAX_RECV_DTOS; + init_attr.cap.max_send_sge = MAX_REGD_BUF_VECTOR_LEN; + init_attr.cap.max_recv_sge = 2; + init_attr.sq_sig_type = IB_SIGNAL_REQ_WR; + init_attr.qp_type = IB_QPT_RC; + + ret = rdma_create_qp(ib_conn->cma_id, device->pd, &init_attr); + if (ret) + goto qp_err; + + ib_conn->qp = ib_conn->cma_id->qp; + iser_err("setting conn %p cma_id %p: fmr_pool %p qp %p\n", + ib_conn, ib_conn->cma_id, + ib_conn->fmr_pool, ib_conn->cma_id->qp); + return ret; + +qp_err: + (void)ib_destroy_fmr_pool(ib_conn->fmr_pool); +fmr_pool_err: + kfree(ib_conn->page_vec); +alloc_err: + iser_err("unable to alloc mem or create resource, err %d\n", ret); + return ret; +} + +/** + * releases the FMR pool, QP and CMA ID objects, returns 0 on success, + * -1 on failure + */ +static int iser_free_ib_conn_res(struct iser_conn *ib_conn) +{ + BUG_ON(ib_conn == NULL); + + iser_err("freeing conn %p cma_id %p fmr pool %p qp %p\n", + ib_conn, ib_conn->cma_id, + ib_conn->fmr_pool, ib_conn->qp); + + /* qp is created only once both addr & route are resolved */ + if (ib_conn->fmr_pool != NULL) + ib_destroy_fmr_pool(ib_conn->fmr_pool); + + if (ib_conn->qp != NULL) + rdma_destroy_qp(ib_conn->cma_id); + + if (ib_conn->cma_id != NULL) + rdma_destroy_id(ib_conn->cma_id); + + ib_conn->fmr_pool = NULL; + ib_conn->qp = NULL; + ib_conn->cma_id = NULL; + kfree(ib_conn->page_vec); + + return 0; +} + +/** + * based on the resolved device node GUID see if there already allocated + * device for this device. If there's no such, create one. + */ +static +struct iser_device *iser_device_find_by_ib_device(struct rdma_cm_id *cma_id) +{ + struct list_head *p_list; + struct iser_device *device = NULL; + + mutex_lock(&ig.device_list_mutex); + + p_list = ig.device_list.next; + while (p_list != &ig.device_list) { + device = list_entry(p_list, struct iser_device, ig_list); + /* find if there's a match using the node GUID */ + if (device->ib_device->node_guid == cma_id->device->node_guid) + break; + } + + if (device == NULL) { + device = kzalloc(sizeof *device, GFP_KERNEL); + if (device == NULL) + goto out; + /* assign this device to the device */ + device->ib_device = cma_id->device; + /* init the device and link it into ig device list */ + if (iser_create_device_ib_res(device)) { + kfree(device); + device = NULL; + goto out; + } + list_add(&device->ig_list, &ig.device_list); + } +out: + BUG_ON(device == NULL); + device->refcount++; + mutex_unlock(&ig.device_list_mutex); + return device; +} + +/* if there's no demand for this device, release it */ +static void iser_device_try_release(struct iser_device *device) +{ + mutex_lock(&ig.device_list_mutex); + device->refcount--; + iser_err("device %p refcount %d\n",device,device->refcount); + if (!device->refcount) { + iser_free_device_ib_res(device); + list_del(&device->ig_list); + kfree(device); + } + mutex_unlock(&ig.device_list_mutex); +} + +int iser_conn_state_comp(struct iser_conn *ib_conn, + enum iser_ib_conn_state comp) +{ + int ret; + + spin_lock_bh(&ib_conn->lock); + ret = (ib_conn->state == comp); + spin_unlock_bh(&ib_conn->lock); + return ret; +} + +static int iser_conn_state_comp_exch(struct iser_conn *ib_conn, + enum iser_ib_conn_state comp, + enum iser_ib_conn_state exch) +{ + int ret; + + spin_lock_bh(&ib_conn->lock); + if ((ret = (ib_conn->state == comp))) + ib_conn->state = exch; + spin_unlock_bh(&ib_conn->lock); + return ret; +} + +/** + * triggers start of the disconnect procedures and wait for them to be done + */ +void iser_conn_terminate(struct iser_conn *ib_conn) +{ + int err = 0; + + /* change the ib conn state only if the conn is UP, however always call + * rdma_disconnect since this is the only way to cause the CMA to change + * the QP state to ERROR + */ + + iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP, ISER_CONN_TERMINATING); + err = rdma_disconnect(ib_conn->cma_id); + if (err) + iser_err("Failed to disconnect, conn: 0x%p err %d\n", + ib_conn,err); + + wait_event_interruptible(ib_conn->wait, + ib_conn->state == ISER_CONN_DOWN); + + iser_conn_release(ib_conn); +} + +static void iser_connect_error(struct rdma_cm_id *cma_id) +{ + struct iser_conn *ib_conn; + ib_conn = (struct iser_conn *)cma_id->context; + + ib_conn->state = ISER_CONN_DOWN; + wake_up_interruptible(&ib_conn->wait); +} + +static void iser_addr_handler(struct rdma_cm_id *cma_id) +{ + struct iser_device *device; + struct iser_conn *ib_conn; + int ret; + + device = iser_device_find_by_ib_device(cma_id); + ib_conn = (struct iser_conn *)cma_id->context; + ib_conn->device = device; + + ret = rdma_resolve_route(cma_id, 1000); + if (ret) { + iser_err("resolve route failed: %d\n", ret); + iser_connect_error(cma_id); + } + return; +} + +static void iser_route_handler(struct rdma_cm_id *cma_id) +{ + struct rdma_conn_param conn_param; + int ret; + + ret = iser_create_ib_conn_res((struct iser_conn *)cma_id->context); + if (ret) + goto failure; + + iser_dbg("path.mtu is %d setting it to %d\n", + cma_id->route.path_rec->mtu, IB_MTU_1024); + + /* we must set the MTU to 1024 as this is what the target is assuming */ + if (cma_id->route.path_rec->mtu > IB_MTU_1024) + cma_id->route.path_rec->mtu = IB_MTU_1024; + + memset(&conn_param, 0, sizeof conn_param); + conn_param.responder_resources = 4; + conn_param.initiator_depth = 1; + conn_param.retry_count = 7; + conn_param.rnr_retry_count = 6; + + ret = rdma_connect(cma_id, &conn_param); + if (ret) { + iser_err("failure connecting: %d\n", ret); + goto failure; + } + + return; +failure: + iser_connect_error(cma_id); +} + +static void iser_connected_handler(struct rdma_cm_id *cma_id) +{ + struct iser_conn *ib_conn; + + ib_conn = (struct iser_conn *)cma_id->context; + ib_conn->state = ISER_CONN_UP; + wake_up_interruptible(&ib_conn->wait); +} + +static void iser_disconnected_handler(struct rdma_cm_id *cma_id) +{ + struct iser_conn *ib_conn; + + ib_conn = (struct iser_conn *)cma_id->context; + ib_conn->disc_evt_flag = 1; + + /* getting here when the state is UP means that the conn is being * + * terminated asynchronously from the iSCSI layer's perspective. */ + if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP, + ISER_CONN_TERMINATING)) + iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn, + ISCSI_ERR_CONN_FAILED); + + /* Complete the termination process if no posts are pending */ + if ((atomic_read(&ib_conn->post_recv_buf_count) == 0) && + (atomic_read(&ib_conn->post_send_buf_count) == 0)) { + ib_conn->state = ISER_CONN_DOWN; + wake_up_interruptible(&ib_conn->wait); + } +} + +static int iser_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event) +{ + int ret = 0; + + iser_err("event %d conn %p id %p\n",event->event,cma_id->context,cma_id); + + switch (event->event) { + case RDMA_CM_EVENT_ADDR_RESOLVED: + iser_addr_handler(cma_id); + break; + case RDMA_CM_EVENT_ROUTE_RESOLVED: + iser_route_handler(cma_id); + break; + case RDMA_CM_EVENT_ESTABLISHED: + iser_connected_handler(cma_id); + break; + case RDMA_CM_EVENT_ADDR_ERROR: + case RDMA_CM_EVENT_ROUTE_ERROR: + case RDMA_CM_EVENT_CONNECT_ERROR: + case RDMA_CM_EVENT_UNREACHABLE: + case RDMA_CM_EVENT_REJECTED: + iser_err("event: %d, error: %d\n", event->event, event->status); + iser_connect_error(cma_id); + break; + case RDMA_CM_EVENT_DISCONNECTED: + iser_disconnected_handler(cma_id); + break; + case RDMA_CM_EVENT_DEVICE_REMOVAL: + BUG(); + break; + case RDMA_CM_EVENT_CONNECT_RESPONSE: + BUG(); + break; + case RDMA_CM_EVENT_CONNECT_REQUEST: + default: + break; + } + return ret; +} + +int iser_conn_init(struct iser_conn **ibconn) +{ + struct iser_conn *ib_conn; + + ib_conn = kzalloc(sizeof *ib_conn, GFP_KERNEL); + if (!ib_conn) { + iser_err("can't alloc memory for struct iser_conn\n"); + return -ENOMEM; + } + ib_conn->state = ISER_CONN_INIT; + init_waitqueue_head(&ib_conn->wait); + atomic_set(&ib_conn->post_recv_buf_count, 0); + atomic_set(&ib_conn->post_send_buf_count, 0); + INIT_WORK(&ib_conn->comperror_work, iser_comp_error_worker, + ib_conn); + INIT_LIST_HEAD(&ib_conn->conn_list); + spin_lock_init(&ib_conn->lock); + + *ibconn = ib_conn; + return 0; +} + + /** + * starts the process of connecting to the target + * sleeps untill the connection is established or rejected + */ +int iser_connect(struct iser_conn *ib_conn, + struct sockaddr_in *src_addr, + struct sockaddr_in *dst_addr, + int non_blocking) +{ + struct sockaddr *src, *dst; + int err = 0; + + sprintf(ib_conn->name,"%d.%d.%d.%d:%d", + NIPQUAD(dst_addr->sin_addr.s_addr), dst_addr->sin_port); + + /* the device is known only --after-- address resolution */ + ib_conn->device = NULL; + + iser_err("connecting to: %d.%d.%d.%d, port 0x%x\n", + NIPQUAD(dst_addr->sin_addr), dst_addr->sin_port); + + ib_conn->state = ISER_CONN_PENDING; + + ib_conn->cma_id = rdma_create_id(iser_cma_handler, + (void *)ib_conn, + RDMA_PS_TCP); + if (IS_ERR(ib_conn->cma_id)) { + err = PTR_ERR(ib_conn->cma_id); + iser_err("rdma_create_id failed: %d\n", err); + goto id_failure; + } + + src = (struct sockaddr *)src_addr; + dst = (struct sockaddr *)dst_addr; + err = rdma_resolve_addr(ib_conn->cma_id, src, dst, 1000); + if (err) { + iser_err("rdma_resolve_addr failed: %d\n", err); + goto addr_failure; + } + + if (!non_blocking) { + wait_event_interruptible(ib_conn->wait, + (ib_conn->state != ISER_CONN_PENDING)); + + if (ib_conn->state != ISER_CONN_UP) { + err = -EIO; + goto connect_failure; + } + } + + mutex_lock(&ig.connlist_mutex); + list_add(&ib_conn->conn_list, &ig.connlist); + mutex_unlock(&ig.connlist_mutex); + return 0; + +id_failure: + ib_conn->cma_id = NULL; +addr_failure: + ib_conn->state = ISER_CONN_DOWN; +connect_failure: + iser_conn_release(ib_conn); + return err; +} + +/** + * Frees all conn objects and deallocs conn descriptor + */ +void iser_conn_release(struct iser_conn *ib_conn) +{ + struct iser_device *device = ib_conn->device; + + BUG_ON(ib_conn->state != ISER_CONN_DOWN); + + mutex_lock(&ig.connlist_mutex); + list_del(&ib_conn->conn_list); + mutex_unlock(&ig.connlist_mutex); + + iser_free_ib_conn_res(ib_conn); + ib_conn->device = NULL; + /* on EVENT_ADDR_ERROR there's no device yet for this conn */ + if (device != NULL) + iser_device_try_release(device); + kfree(ib_conn); +} + + +/** + * iser_reg_page_vec - Register physical memory + * + * returns: 0 on success, errno code on failure + */ +int iser_reg_page_vec(struct iser_conn *ib_conn, + struct iser_page_vec *page_vec, + struct iser_mem_reg *mem_reg) +{ + struct ib_pool_fmr *mem; + u64 io_addr; + u64 *page_list; + int status; + + page_list = page_vec->pages; + io_addr = page_list[0]; + + mem = ib_fmr_pool_map_phys(ib_conn->fmr_pool, + page_list, + page_vec->length, + &io_addr); + + if (IS_ERR(mem)) { + status = (int)PTR_ERR(mem); + iser_err("ib_fmr_pool_map_phys failed: %d\n", status); + return status; + } + + mem_reg->lkey = mem->fmr->lkey; + mem_reg->rkey = mem->fmr->rkey; + mem_reg->len = page_vec->length * PAGE_SIZE; + mem_reg->va = io_addr; + mem_reg->mem_h = (void *)mem; + + mem_reg->va += page_vec->offset; + mem_reg->len = page_vec->data_size; + + iser_dbg("PHYSICAL Mem.register, [PHYS p_array: 0x%p, sz: %d, " + "entry[0]: (0x%08lx,%ld)] -> " + "[lkey: 0x%08X mem_h: 0x%p va: 0x%08lX sz: %ld]\n", + page_vec, page_vec->length, + (unsigned long)page_vec->pages[0], + (unsigned long)page_vec->data_size, + (unsigned int)mem_reg->lkey, mem_reg->mem_h, + (unsigned long)mem_reg->va, (unsigned long)mem_reg->len); + return 0; +} + +/** + * Unregister (previosuly registered) memory. + */ +void iser_unreg_mem(struct iser_mem_reg *reg) +{ + int ret; + + iser_dbg("PHYSICAL Mem.Unregister mem_h %p\n",reg->mem_h); + + ret = ib_fmr_pool_unmap((struct ib_pool_fmr *)reg->mem_h); + if (ret) + iser_err("ib_fmr_pool_unmap failed %d\n", ret); + + reg->mem_h = NULL; +} + +/** + * iser_dto_to_iov - builds IOV from a dto descriptor + */ +static void iser_dto_to_iov(struct iser_dto *dto, struct ib_sge *iov, int iov_len) +{ + int i; + struct ib_sge *sge; + struct iser_regd_buf *regd_buf; + + if (dto->regd_vector_len > iov_len) { + iser_err("iov size %d too small for posting dto of len %d\n", + iov_len, dto->regd_vector_len); + BUG(); + } + + for (i = 0; i < dto->regd_vector_len; i++) { + sge = &iov[i]; + regd_buf = dto->regd[i]; + + sge->addr = regd_buf->reg.va; + sge->length = regd_buf->reg.len; + sge->lkey = regd_buf->reg.lkey; + + if (dto->used_sz[i] > 0) /* Adjust size */ + sge->length = dto->used_sz[i]; + + /* offset and length should not exceed the regd buf length */ + if (sge->length + dto->offset[i] > regd_buf->reg.len) { + iser_err("Used len:%ld + offset:%d, exceed reg.buf.len:" + "%ld in dto:0x%p [%d], va:0x%08lX\n", + (unsigned long)sge->length, dto->offset[i], + (unsigned long)regd_buf->reg.len, dto, i, + (unsigned long)sge->addr); + BUG(); + } + + sge->addr += dto->offset[i]; /* Adjust offset */ + } +} + +/** + * iser_post_recv - Posts a receive buffer. + * + * returns 0 on success, -1 on failure + */ +int iser_post_recv(struct iser_desc *rx_desc) +{ + int ib_ret, ret_val = 0; + struct ib_recv_wr recv_wr, *recv_wr_failed; + struct ib_sge iov[2]; + struct iser_conn *ib_conn; + struct iser_dto *recv_dto = &rx_desc->dto; + + /* Retrieve conn */ + ib_conn = recv_dto->conn->ib_conn; + + iser_dto_to_iov(recv_dto, iov, 2); + + recv_wr.next = NULL; + recv_wr.sg_list = iov; + recv_wr.num_sge = recv_dto->regd_vector_len; + recv_wr.wr_id = (unsigned long)rx_desc; + + atomic_inc(&ib_conn->post_recv_buf_count); + ib_ret = ib_post_recv(ib_conn->qp, &recv_wr, &recv_wr_failed); + if (ib_ret) { + iser_err("ib_post_recv failed ret=%d\n", ib_ret); + atomic_dec(&ib_conn->post_recv_buf_count); + ret_val = -1; + } + + return ret_val; +} + +/** + * iser_start_send - Initiate a Send DTO operation + * + * returns 0 on success, -1 on failure + */ +int iser_post_send(struct iser_desc *tx_desc) +{ + int ib_ret, ret_val = 0; + struct ib_send_wr send_wr, *send_wr_failed; + struct ib_sge iov[MAX_REGD_BUF_VECTOR_LEN]; + struct iser_conn *ib_conn; + struct iser_dto *dto = &tx_desc->dto; + + ib_conn = dto->conn->ib_conn; + + iser_dto_to_iov(dto, iov, MAX_REGD_BUF_VECTOR_LEN); + + send_wr.next = NULL; + send_wr.wr_id = (unsigned long)tx_desc; + send_wr.sg_list = iov; + send_wr.num_sge = dto->regd_vector_len; + send_wr.opcode = IB_WR_SEND; + send_wr.send_flags = dto->notify_enable ? IB_SEND_SIGNALED : 0; + + atomic_inc(&ib_conn->post_send_buf_count); + + ib_ret = ib_post_send(ib_conn->qp, &send_wr, &send_wr_failed); + if (ib_ret) { + iser_err("Failed to start SEND DTO, dto: 0x%p, IOV len: %d\n", + dto, dto->regd_vector_len); + iser_err("ib_post_send failed, ret:%d\n", ib_ret); + atomic_dec(&ib_conn->post_send_buf_count); + ret_val = -1; + } + + return ret_val; +} + +static void iser_comp_error_worker(void *data) +{ + struct iser_conn *ib_conn = data; + + /* getting here when the state is UP means that the conn is being * + * terminated asynchronously from the iSCSI layer's perspective. */ + if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP, + ISER_CONN_TERMINATING)) + iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn, + ISCSI_ERR_CONN_FAILED); + + /* complete the termination process if disconnect event was delivered * + * note there are no more non completed posts to the QP */ + if (ib_conn->disc_evt_flag) { + ib_conn->state = ISER_CONN_DOWN; + wake_up_interruptible(&ib_conn->wait); + } +} + +static void iser_handle_comp_error(struct iser_desc *desc) +{ + struct iser_dto *dto = &desc->dto; + struct iser_conn *ib_conn = dto->conn->ib_conn; + + iser_dto_buffs_release(dto); + + if (desc->type == ISCSI_RX) { + kfree(desc->data); + kmem_cache_free(ig.desc_cache, desc); + atomic_dec(&ib_conn->post_recv_buf_count); + } else { /* type is TX control/command/dataout */ + if (desc->type == ISCSI_TX_DATAOUT) + kmem_cache_free(ig.desc_cache, desc); + atomic_dec(&ib_conn->post_send_buf_count); + } + + if (atomic_read(&ib_conn->post_recv_buf_count) == 0 && + atomic_read(&ib_conn->post_send_buf_count) == 0) + schedule_work(&ib_conn->comperror_work); +} + +static void iser_cq_tasklet_fn(unsigned long data) +{ + struct iser_device *device = (struct iser_device *)data; + struct ib_cq *cq = device->cq; + struct ib_wc wc; + struct iser_desc *desc; + unsigned long xfer_len; + + while (ib_poll_cq(cq, 1, &wc) == 1) { + desc = (struct iser_desc *) (unsigned long) wc.wr_id; + BUG_ON(desc == NULL); + + if (wc.status == IB_WC_SUCCESS) { + if (desc->type == ISCSI_RX) { + xfer_len = (unsigned long)wc.byte_len; + iser_rcv_completion(desc, xfer_len); + } else /* type == ISCSI_TX_CONTROL/SCSI_CMD/DOUT */ + iser_snd_completion(desc); + } else { + iser_err("comp w. error op %d status %d\n",desc->type,wc.status); + iser_handle_comp_error(desc); + } + } + /* #warning "it is assumed here that arming CQ only once its empty" * + * " would not cause interrupts to be missed" */ + ib_req_notify_cq(cq, IB_CQ_NEXT_COMP); +} + +static void iser_cq_callback(struct ib_cq *cq, void *cq_context) +{ + struct iser_device *device = (struct iser_device *)cq_context; + + tasklet_schedule(&device->cq_tasklet); +}