/*
* 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 <asm/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/version.h>
#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_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, 0);
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 |
IB_ACCESS_REMOTE_WRITE |
IB_ACCESS_REMOTE_READ);
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 = SHIFT_4K;
/* 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_DEF_XMIT_CMDS_MAX * 2;
params.dirty_watermark = ISCSI_DEF_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_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);
if (ib_conn->iser_conn)
ib_conn->iser_conn->ib_conn = NULL;
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 * SIZE_4K;
mem_reg->va = io_addr;
mem_reg->is_fmr = 1;
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->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->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_handle_comp_error(struct iser_desc *desc)
{
struct iser_dto *dto = &desc->dto;
struct iser_conn *ib_conn = dto->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) {
/* 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_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);
}
