2 * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
3 * Copyright (c) 2005, 2006 Cisco Systems. All rights reserved.
5 * This software is available to you under a choice of one of two
6 * licenses. You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the
9 * OpenIB.org BSD license below:
11 * Redistribution and use in source and binary forms, with or
12 * without modification, are permitted provided that the following
15 * - Redistributions of source code must retain the above
16 * copyright notice, this list of conditions and the following
19 * - Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials
22 * provided with the distribution.
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/delay.h>
37 #include "iscsi_iser.h"
39 #define ISCSI_ISER_MAX_CONN 8
40 #define ISER_MAX_CQ_LEN ((ISER_QP_MAX_RECV_DTOS + \
41 ISER_QP_MAX_REQ_DTOS) * \
44 static void iser_cq_tasklet_fn(unsigned long data);
45 static void iser_cq_callback(struct ib_cq *cq, void *cq_context);
47 static void iser_cq_event_callback(struct ib_event *cause, void *context)
49 iser_err("got cq event %d \n", cause->event);
52 static void iser_qp_event_callback(struct ib_event *cause, void *context)
54 iser_err("got qp event %d\n",cause->event);
58 * iser_create_device_ib_res - creates Protection Domain (PD), Completion
59 * Queue (CQ), DMA Memory Region (DMA MR) with the device associated with
62 * returns 0 on success, -1 on failure
64 static int iser_create_device_ib_res(struct iser_device *device)
66 device->pd = ib_alloc_pd(device->ib_device);
67 if (IS_ERR(device->pd))
70 device->cq = ib_create_cq(device->ib_device,
72 iser_cq_event_callback,
75 if (IS_ERR(device->cq))
78 if (ib_req_notify_cq(device->cq, IB_CQ_NEXT_COMP))
81 tasklet_init(&device->cq_tasklet,
83 (unsigned long)device);
85 device->mr = ib_get_dma_mr(device->pd, IB_ACCESS_LOCAL_WRITE |
86 IB_ACCESS_REMOTE_WRITE |
87 IB_ACCESS_REMOTE_READ);
88 if (IS_ERR(device->mr))
94 tasklet_kill(&device->cq_tasklet);
96 ib_destroy_cq(device->cq);
98 ib_dealloc_pd(device->pd);
100 iser_err("failed to allocate an IB resource\n");
105 * iser_free_device_ib_res - destroy/dealloc/dereg the DMA MR,
106 * CQ and PD created with the device associated with the adapator.
108 static void iser_free_device_ib_res(struct iser_device *device)
110 BUG_ON(device->mr == NULL);
112 tasklet_kill(&device->cq_tasklet);
114 (void)ib_dereg_mr(device->mr);
115 (void)ib_destroy_cq(device->cq);
116 (void)ib_dealloc_pd(device->pd);
124 * iser_create_ib_conn_res - Creates FMR pool and Queue-Pair (QP)
126 * returns 0 on success, -1 on failure
128 static int iser_create_ib_conn_res(struct iser_conn *ib_conn)
130 struct iser_device *device;
131 struct ib_qp_init_attr init_attr;
133 struct ib_fmr_pool_param params;
135 BUG_ON(ib_conn->device == NULL);
137 device = ib_conn->device;
139 ib_conn->page_vec = kmalloc(sizeof(struct iser_page_vec) +
140 (sizeof(u64) * (ISCSI_ISER_SG_TABLESIZE +1)),
142 if (!ib_conn->page_vec) {
146 ib_conn->page_vec->pages = (u64 *) (ib_conn->page_vec + 1);
148 params.page_shift = SHIFT_4K;
149 /* when the first/last SG element are not start/end *
150 * page aligned, the map whould be of N+1 pages */
151 params.max_pages_per_fmr = ISCSI_ISER_SG_TABLESIZE + 1;
152 /* make the pool size twice the max number of SCSI commands *
153 * the ML is expected to queue, watermark for unmap at 50% */
154 params.pool_size = ISCSI_DEF_XMIT_CMDS_MAX * 2;
155 params.dirty_watermark = ISCSI_DEF_XMIT_CMDS_MAX;
157 params.flush_function = NULL;
158 params.access = (IB_ACCESS_LOCAL_WRITE |
159 IB_ACCESS_REMOTE_WRITE |
160 IB_ACCESS_REMOTE_READ);
162 ib_conn->fmr_pool = ib_create_fmr_pool(device->pd, ¶ms);
163 if (IS_ERR(ib_conn->fmr_pool)) {
164 ret = PTR_ERR(ib_conn->fmr_pool);
168 memset(&init_attr, 0, sizeof init_attr);
170 init_attr.event_handler = iser_qp_event_callback;
171 init_attr.qp_context = (void *)ib_conn;
172 init_attr.send_cq = device->cq;
173 init_attr.recv_cq = device->cq;
174 init_attr.cap.max_send_wr = ISER_QP_MAX_REQ_DTOS;
175 init_attr.cap.max_recv_wr = ISER_QP_MAX_RECV_DTOS;
176 init_attr.cap.max_send_sge = MAX_REGD_BUF_VECTOR_LEN;
177 init_attr.cap.max_recv_sge = 2;
178 init_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
179 init_attr.qp_type = IB_QPT_RC;
181 ret = rdma_create_qp(ib_conn->cma_id, device->pd, &init_attr);
185 ib_conn->qp = ib_conn->cma_id->qp;
186 iser_err("setting conn %p cma_id %p: fmr_pool %p qp %p\n",
187 ib_conn, ib_conn->cma_id,
188 ib_conn->fmr_pool, ib_conn->cma_id->qp);
192 (void)ib_destroy_fmr_pool(ib_conn->fmr_pool);
194 kfree(ib_conn->page_vec);
196 iser_err("unable to alloc mem or create resource, err %d\n", ret);
201 * releases the FMR pool, QP and CMA ID objects, returns 0 on success,
204 static int iser_free_ib_conn_res(struct iser_conn *ib_conn)
206 BUG_ON(ib_conn == NULL);
208 iser_err("freeing conn %p cma_id %p fmr pool %p qp %p\n",
209 ib_conn, ib_conn->cma_id,
210 ib_conn->fmr_pool, ib_conn->qp);
212 /* qp is created only once both addr & route are resolved */
213 if (ib_conn->fmr_pool != NULL)
214 ib_destroy_fmr_pool(ib_conn->fmr_pool);
216 if (ib_conn->qp != NULL)
217 rdma_destroy_qp(ib_conn->cma_id);
219 if (ib_conn->cma_id != NULL)
220 rdma_destroy_id(ib_conn->cma_id);
222 ib_conn->fmr_pool = NULL;
224 ib_conn->cma_id = NULL;
225 kfree(ib_conn->page_vec);
231 * based on the resolved device node GUID see if there already allocated
232 * device for this device. If there's no such, create one.
235 struct iser_device *iser_device_find_by_ib_device(struct rdma_cm_id *cma_id)
237 struct iser_device *device;
239 mutex_lock(&ig.device_list_mutex);
241 list_for_each_entry(device, &ig.device_list, ig_list)
242 /* find if there's a match using the node GUID */
243 if (device->ib_device->node_guid == cma_id->device->node_guid)
246 device = kzalloc(sizeof *device, GFP_KERNEL);
250 /* assign this device to the device */
251 device->ib_device = cma_id->device;
252 /* init the device and link it into ig device list */
253 if (iser_create_device_ib_res(device)) {
258 list_add(&device->ig_list, &ig.device_list);
263 mutex_unlock(&ig.device_list_mutex);
267 /* if there's no demand for this device, release it */
268 static void iser_device_try_release(struct iser_device *device)
270 mutex_lock(&ig.device_list_mutex);
272 iser_err("device %p refcount %d\n",device,device->refcount);
273 if (!device->refcount) {
274 iser_free_device_ib_res(device);
275 list_del(&device->ig_list);
278 mutex_unlock(&ig.device_list_mutex);
281 int iser_conn_state_comp(struct iser_conn *ib_conn,
282 enum iser_ib_conn_state comp)
286 spin_lock_bh(&ib_conn->lock);
287 ret = (ib_conn->state == comp);
288 spin_unlock_bh(&ib_conn->lock);
292 static int iser_conn_state_comp_exch(struct iser_conn *ib_conn,
293 enum iser_ib_conn_state comp,
294 enum iser_ib_conn_state exch)
298 spin_lock_bh(&ib_conn->lock);
299 if ((ret = (ib_conn->state == comp)))
300 ib_conn->state = exch;
301 spin_unlock_bh(&ib_conn->lock);
306 * Frees all conn objects and deallocs conn descriptor
308 static void iser_conn_release(struct iser_conn *ib_conn)
310 struct iser_device *device = ib_conn->device;
312 BUG_ON(ib_conn->state != ISER_CONN_DOWN);
314 mutex_lock(&ig.connlist_mutex);
315 list_del(&ib_conn->conn_list);
316 mutex_unlock(&ig.connlist_mutex);
318 iser_free_ib_conn_res(ib_conn);
319 ib_conn->device = NULL;
320 /* on EVENT_ADDR_ERROR there's no device yet for this conn */
322 iser_device_try_release(device);
323 if (ib_conn->iser_conn)
324 ib_conn->iser_conn->ib_conn = NULL;
325 iscsi_destroy_endpoint(ib_conn->ep);
328 void iser_conn_get(struct iser_conn *ib_conn)
330 atomic_inc(&ib_conn->refcount);
333 void iser_conn_put(struct iser_conn *ib_conn)
335 if (atomic_dec_and_test(&ib_conn->refcount))
336 iser_conn_release(ib_conn);
340 * triggers start of the disconnect procedures and wait for them to be done
342 void iser_conn_terminate(struct iser_conn *ib_conn)
346 /* change the ib conn state only if the conn is UP, however always call
347 * rdma_disconnect since this is the only way to cause the CMA to change
348 * the QP state to ERROR
351 iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP, ISER_CONN_TERMINATING);
352 err = rdma_disconnect(ib_conn->cma_id);
354 iser_err("Failed to disconnect, conn: 0x%p err %d\n",
357 wait_event_interruptible(ib_conn->wait,
358 ib_conn->state == ISER_CONN_DOWN);
360 iser_conn_put(ib_conn);
363 static void iser_connect_error(struct rdma_cm_id *cma_id)
365 struct iser_conn *ib_conn;
366 ib_conn = (struct iser_conn *)cma_id->context;
368 ib_conn->state = ISER_CONN_DOWN;
369 wake_up_interruptible(&ib_conn->wait);
372 static void iser_addr_handler(struct rdma_cm_id *cma_id)
374 struct iser_device *device;
375 struct iser_conn *ib_conn;
378 device = iser_device_find_by_ib_device(cma_id);
380 iser_err("device lookup/creation failed\n");
381 iser_connect_error(cma_id);
385 ib_conn = (struct iser_conn *)cma_id->context;
386 ib_conn->device = device;
388 ret = rdma_resolve_route(cma_id, 1000);
390 iser_err("resolve route failed: %d\n", ret);
391 iser_connect_error(cma_id);
395 static void iser_route_handler(struct rdma_cm_id *cma_id)
397 struct rdma_conn_param conn_param;
400 ret = iser_create_ib_conn_res((struct iser_conn *)cma_id->context);
404 memset(&conn_param, 0, sizeof conn_param);
405 conn_param.responder_resources = 4;
406 conn_param.initiator_depth = 1;
407 conn_param.retry_count = 7;
408 conn_param.rnr_retry_count = 6;
410 ret = rdma_connect(cma_id, &conn_param);
412 iser_err("failure connecting: %d\n", ret);
418 iser_connect_error(cma_id);
421 static void iser_connected_handler(struct rdma_cm_id *cma_id)
423 struct iser_conn *ib_conn;
425 ib_conn = (struct iser_conn *)cma_id->context;
426 ib_conn->state = ISER_CONN_UP;
427 wake_up_interruptible(&ib_conn->wait);
430 static void iser_disconnected_handler(struct rdma_cm_id *cma_id)
432 struct iser_conn *ib_conn;
434 ib_conn = (struct iser_conn *)cma_id->context;
435 ib_conn->disc_evt_flag = 1;
437 /* getting here when the state is UP means that the conn is being *
438 * terminated asynchronously from the iSCSI layer's perspective. */
439 if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP,
440 ISER_CONN_TERMINATING))
441 iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn,
442 ISCSI_ERR_CONN_FAILED);
444 /* Complete the termination process if no posts are pending */
445 if ((atomic_read(&ib_conn->post_recv_buf_count) == 0) &&
446 (atomic_read(&ib_conn->post_send_buf_count) == 0)) {
447 ib_conn->state = ISER_CONN_DOWN;
448 wake_up_interruptible(&ib_conn->wait);
452 static int iser_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
456 iser_err("event %d conn %p id %p\n",event->event,cma_id->context,cma_id);
458 switch (event->event) {
459 case RDMA_CM_EVENT_ADDR_RESOLVED:
460 iser_addr_handler(cma_id);
462 case RDMA_CM_EVENT_ROUTE_RESOLVED:
463 iser_route_handler(cma_id);
465 case RDMA_CM_EVENT_ESTABLISHED:
466 iser_connected_handler(cma_id);
468 case RDMA_CM_EVENT_ADDR_ERROR:
469 case RDMA_CM_EVENT_ROUTE_ERROR:
470 case RDMA_CM_EVENT_CONNECT_ERROR:
471 case RDMA_CM_EVENT_UNREACHABLE:
472 case RDMA_CM_EVENT_REJECTED:
473 iser_err("event: %d, error: %d\n", event->event, event->status);
474 iser_connect_error(cma_id);
476 case RDMA_CM_EVENT_DISCONNECTED:
477 case RDMA_CM_EVENT_DEVICE_REMOVAL:
478 case RDMA_CM_EVENT_ADDR_CHANGE:
479 iser_disconnected_handler(cma_id);
482 iser_err("Unexpected RDMA CM event (%d)\n", event->event);
488 void iser_conn_init(struct iser_conn *ib_conn)
490 ib_conn->state = ISER_CONN_INIT;
491 init_waitqueue_head(&ib_conn->wait);
492 atomic_set(&ib_conn->post_recv_buf_count, 0);
493 atomic_set(&ib_conn->post_send_buf_count, 0);
494 atomic_set(&ib_conn->refcount, 1);
495 INIT_LIST_HEAD(&ib_conn->conn_list);
496 spin_lock_init(&ib_conn->lock);
500 * starts the process of connecting to the target
501 * sleeps until the connection is established or rejected
503 int iser_connect(struct iser_conn *ib_conn,
504 struct sockaddr_in *src_addr,
505 struct sockaddr_in *dst_addr,
508 struct sockaddr *src, *dst;
511 sprintf(ib_conn->name, "%pI4:%d",
512 &dst_addr->sin_addr.s_addr, dst_addr->sin_port);
514 /* the device is known only --after-- address resolution */
515 ib_conn->device = NULL;
517 iser_err("connecting to: %pI4, port 0x%x\n",
518 &dst_addr->sin_addr, dst_addr->sin_port);
520 ib_conn->state = ISER_CONN_PENDING;
522 ib_conn->cma_id = rdma_create_id(iser_cma_handler,
525 if (IS_ERR(ib_conn->cma_id)) {
526 err = PTR_ERR(ib_conn->cma_id);
527 iser_err("rdma_create_id failed: %d\n", err);
531 src = (struct sockaddr *)src_addr;
532 dst = (struct sockaddr *)dst_addr;
533 err = rdma_resolve_addr(ib_conn->cma_id, src, dst, 1000);
535 iser_err("rdma_resolve_addr failed: %d\n", err);
540 wait_event_interruptible(ib_conn->wait,
541 (ib_conn->state != ISER_CONN_PENDING));
543 if (ib_conn->state != ISER_CONN_UP) {
545 goto connect_failure;
549 mutex_lock(&ig.connlist_mutex);
550 list_add(&ib_conn->conn_list, &ig.connlist);
551 mutex_unlock(&ig.connlist_mutex);
555 ib_conn->cma_id = NULL;
557 ib_conn->state = ISER_CONN_DOWN;
559 iser_conn_release(ib_conn);
564 * iser_reg_page_vec - Register physical memory
566 * returns: 0 on success, errno code on failure
568 int iser_reg_page_vec(struct iser_conn *ib_conn,
569 struct iser_page_vec *page_vec,
570 struct iser_mem_reg *mem_reg)
572 struct ib_pool_fmr *mem;
577 page_list = page_vec->pages;
578 io_addr = page_list[0];
580 mem = ib_fmr_pool_map_phys(ib_conn->fmr_pool,
586 status = (int)PTR_ERR(mem);
587 iser_err("ib_fmr_pool_map_phys failed: %d\n", status);
591 mem_reg->lkey = mem->fmr->lkey;
592 mem_reg->rkey = mem->fmr->rkey;
593 mem_reg->len = page_vec->length * SIZE_4K;
594 mem_reg->va = io_addr;
596 mem_reg->mem_h = (void *)mem;
598 mem_reg->va += page_vec->offset;
599 mem_reg->len = page_vec->data_size;
601 iser_dbg("PHYSICAL Mem.register, [PHYS p_array: 0x%p, sz: %d, "
602 "entry[0]: (0x%08lx,%ld)] -> "
603 "[lkey: 0x%08X mem_h: 0x%p va: 0x%08lX sz: %ld]\n",
604 page_vec, page_vec->length,
605 (unsigned long)page_vec->pages[0],
606 (unsigned long)page_vec->data_size,
607 (unsigned int)mem_reg->lkey, mem_reg->mem_h,
608 (unsigned long)mem_reg->va, (unsigned long)mem_reg->len);
613 * Unregister (previosuly registered) memory.
615 void iser_unreg_mem(struct iser_mem_reg *reg)
619 iser_dbg("PHYSICAL Mem.Unregister mem_h %p\n",reg->mem_h);
621 ret = ib_fmr_pool_unmap((struct ib_pool_fmr *)reg->mem_h);
623 iser_err("ib_fmr_pool_unmap failed %d\n", ret);
629 * iser_dto_to_iov - builds IOV from a dto descriptor
631 static void iser_dto_to_iov(struct iser_dto *dto, struct ib_sge *iov, int iov_len)
635 struct iser_regd_buf *regd_buf;
637 if (dto->regd_vector_len > iov_len) {
638 iser_err("iov size %d too small for posting dto of len %d\n",
639 iov_len, dto->regd_vector_len);
643 for (i = 0; i < dto->regd_vector_len; i++) {
645 regd_buf = dto->regd[i];
647 sge->addr = regd_buf->reg.va;
648 sge->length = regd_buf->reg.len;
649 sge->lkey = regd_buf->reg.lkey;
651 if (dto->used_sz[i] > 0) /* Adjust size */
652 sge->length = dto->used_sz[i];
654 /* offset and length should not exceed the regd buf length */
655 if (sge->length + dto->offset[i] > regd_buf->reg.len) {
656 iser_err("Used len:%ld + offset:%d, exceed reg.buf.len:"
657 "%ld in dto:0x%p [%d], va:0x%08lX\n",
658 (unsigned long)sge->length, dto->offset[i],
659 (unsigned long)regd_buf->reg.len, dto, i,
660 (unsigned long)sge->addr);
664 sge->addr += dto->offset[i]; /* Adjust offset */
669 * iser_post_recv - Posts a receive buffer.
671 * returns 0 on success, -1 on failure
673 int iser_post_recv(struct iser_desc *rx_desc)
675 int ib_ret, ret_val = 0;
676 struct ib_recv_wr recv_wr, *recv_wr_failed;
677 struct ib_sge iov[2];
678 struct iser_conn *ib_conn;
679 struct iser_dto *recv_dto = &rx_desc->dto;
682 ib_conn = recv_dto->ib_conn;
684 iser_dto_to_iov(recv_dto, iov, 2);
687 recv_wr.sg_list = iov;
688 recv_wr.num_sge = recv_dto->regd_vector_len;
689 recv_wr.wr_id = (unsigned long)rx_desc;
691 atomic_inc(&ib_conn->post_recv_buf_count);
692 ib_ret = ib_post_recv(ib_conn->qp, &recv_wr, &recv_wr_failed);
694 iser_err("ib_post_recv failed ret=%d\n", ib_ret);
695 atomic_dec(&ib_conn->post_recv_buf_count);
703 * iser_start_send - Initiate a Send DTO operation
705 * returns 0 on success, -1 on failure
707 int iser_post_send(struct iser_desc *tx_desc)
709 int ib_ret, ret_val = 0;
710 struct ib_send_wr send_wr, *send_wr_failed;
711 struct ib_sge iov[MAX_REGD_BUF_VECTOR_LEN];
712 struct iser_conn *ib_conn;
713 struct iser_dto *dto = &tx_desc->dto;
715 ib_conn = dto->ib_conn;
717 iser_dto_to_iov(dto, iov, MAX_REGD_BUF_VECTOR_LEN);
720 send_wr.wr_id = (unsigned long)tx_desc;
721 send_wr.sg_list = iov;
722 send_wr.num_sge = dto->regd_vector_len;
723 send_wr.opcode = IB_WR_SEND;
724 send_wr.send_flags = dto->notify_enable ? IB_SEND_SIGNALED : 0;
726 atomic_inc(&ib_conn->post_send_buf_count);
728 ib_ret = ib_post_send(ib_conn->qp, &send_wr, &send_wr_failed);
730 iser_err("Failed to start SEND DTO, dto: 0x%p, IOV len: %d\n",
731 dto, dto->regd_vector_len);
732 iser_err("ib_post_send failed, ret:%d\n", ib_ret);
733 atomic_dec(&ib_conn->post_send_buf_count);
740 static void iser_handle_comp_error(struct iser_desc *desc)
742 struct iser_dto *dto = &desc->dto;
743 struct iser_conn *ib_conn = dto->ib_conn;
745 iser_dto_buffs_release(dto);
747 if (desc->type == ISCSI_RX) {
749 kmem_cache_free(ig.desc_cache, desc);
750 atomic_dec(&ib_conn->post_recv_buf_count);
751 } else { /* type is TX control/command/dataout */
752 if (desc->type == ISCSI_TX_DATAOUT)
753 kmem_cache_free(ig.desc_cache, desc);
754 atomic_dec(&ib_conn->post_send_buf_count);
757 if (atomic_read(&ib_conn->post_recv_buf_count) == 0 &&
758 atomic_read(&ib_conn->post_send_buf_count) == 0) {
759 /* getting here when the state is UP means that the conn is *
760 * being terminated asynchronously from the iSCSI layer's *
762 if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP,
763 ISER_CONN_TERMINATING))
764 iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn,
765 ISCSI_ERR_CONN_FAILED);
767 /* complete the termination process if disconnect event was delivered *
768 * note there are no more non completed posts to the QP */
769 if (ib_conn->disc_evt_flag) {
770 ib_conn->state = ISER_CONN_DOWN;
771 wake_up_interruptible(&ib_conn->wait);
776 static void iser_cq_tasklet_fn(unsigned long data)
778 struct iser_device *device = (struct iser_device *)data;
779 struct ib_cq *cq = device->cq;
781 struct iser_desc *desc;
782 unsigned long xfer_len;
784 while (ib_poll_cq(cq, 1, &wc) == 1) {
785 desc = (struct iser_desc *) (unsigned long) wc.wr_id;
786 BUG_ON(desc == NULL);
788 if (wc.status == IB_WC_SUCCESS) {
789 if (desc->type == ISCSI_RX) {
790 xfer_len = (unsigned long)wc.byte_len;
791 iser_rcv_completion(desc, xfer_len);
792 } else /* type == ISCSI_TX_CONTROL/SCSI_CMD/DOUT */
793 iser_snd_completion(desc);
795 iser_err("comp w. error op %d status %d\n",desc->type,wc.status);
796 iser_handle_comp_error(desc);
799 /* #warning "it is assumed here that arming CQ only once its empty" *
800 * " would not cause interrupts to be missed" */
801 ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
804 static void iser_cq_callback(struct ib_cq *cq, void *cq_context)
806 struct iser_device *device = (struct iser_device *)cq_context;
808 tasklet_schedule(&device->cq_tasklet);