[openib-general] [PATCH 3/6] iSER initiator iSCSI PDU and TX/RX completions processing
Or Gerlitz
ogerlitz at voltaire.com
Thu May 11 00:02:19 PDT 2006
This file contains the iSER initiator processing of iSCSI PDUs - controls,
commands and data-outs along with processing of TX and RX completions.
It interacts with the lower level iser code doing the memory registration
and and the cma and verbs calls.
Signed-off-by: Or Gerlitz <ogerlitz at voltaire.com>
--- /usr/src/linux-2.6.17-rc3/drivers/infiniband/ulp/iser-x/iser_initiator.c 1970-01-01 02:00:00.000000000 +0200
+++ /usr/src/linux-2.6.17-rc3/drivers/infiniband/ulp/iser/iser_initiator.c 2006-05-10 15:32:01.000000000 +0300
@@ -0,0 +1,734 @@
+/*
+ * Copyright (c) 2004, 2005, 2006 Voltaire, 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
+ * 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_initiator.c 6964 2006-05-07 11:11:43Z ogerlitz $
+ */
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <asm/io.h>
+#include <asm/scatterlist.h>
+#include <linux/scatterlist.h>
+#include <linux/kfifo.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+
+#include "iscsi_iser.h"
+
+/* Constant PDU lengths calculations */
+#define ISER_TOTAL_HEADERS_LEN (sizeof (struct iser_hdr) + \
+ sizeof (struct iscsi_hdr))
+
+/* iser_dto_add_regd_buff - increments the reference count for *
+ * the registered buffer & adds it to the DTO object */
+static void iser_dto_add_regd_buff(struct iser_dto *dto,
+ struct iser_regd_buf *regd_buf,
+ unsigned long use_offset,
+ unsigned long use_size)
+{
+ int add_idx;
+
+ atomic_inc(®d_buf->ref_count);
+
+ add_idx = dto->regd_vector_len;
+ dto->regd[add_idx] = regd_buf;
+ dto->used_sz[add_idx] = use_size;
+ dto->offset[add_idx] = use_offset;
+
+ dto->regd_vector_len++;
+}
+
+static int iser_dma_map_task_data(struct iscsi_iser_cmd_task *iser_ctask,
+ struct iser_data_buf *data,
+ enum iser_data_dir iser_dir,
+ enum dma_data_direction dma_dir)
+{
+ struct device *dma_device;
+
+ iser_ctask->dir[iser_dir] = 1;
+ dma_device = iser_ctask->iser_conn->ib_conn->device->ib_device->dma_device;
+
+ data->dma_nents = dma_map_sg(dma_device, data->buf, data->size, dma_dir);
+ if (data->dma_nents == 0) {
+ iser_err("dma_map_sg failed!!!\n");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static void iser_dma_unmap_task_data(struct iscsi_iser_cmd_task *iser_ctask)
+{
+ struct device *dma_device;
+ struct iser_data_buf *data;
+
+ dma_device = iser_ctask->iser_conn->ib_conn->device->ib_device->dma_device;
+
+ if (iser_ctask->dir[ISER_DIR_IN]) {
+ data = &iser_ctask->data[ISER_DIR_IN];
+ dma_unmap_sg(dma_device, data->buf, data->size, DMA_FROM_DEVICE);
+ }
+
+ if (iser_ctask->dir[ISER_DIR_OUT]) {
+ data = &iser_ctask->data[ISER_DIR_OUT];
+ dma_unmap_sg(dma_device, data->buf, data->size, DMA_TO_DEVICE);
+ }
+}
+
+/* Register user buffer memory and initialize passive rdma
+ * dto descriptor. Total data size is stored in
+ * iser_ctask->data[ISER_DIR_IN].data_len
+ */
+static int iser_prepare_read_cmd(struct iscsi_cmd_task *ctask,
+ unsigned int edtl)
+
+{
+ struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
+ struct iser_regd_buf *regd_buf;
+ int err;
+ struct iser_hdr *hdr = &iser_ctask->desc.iser_header;
+ struct iser_data_buf *buf_in = &iser_ctask->data[ISER_DIR_IN];
+
+ err = iser_dma_map_task_data(iser_ctask,
+ buf_in,
+ ISER_DIR_IN,
+ DMA_FROM_DEVICE);
+ if (err)
+ return err;
+
+ if (edtl > iser_ctask->data[ISER_DIR_IN].data_len) {
+ iser_err("Total data length: %ld, less than EDTL: "
+ "%d, in READ cmd BHS itt: %d, conn: 0x%p\n",
+ iser_ctask->data[ISER_DIR_IN].data_len, edtl,
+ ctask->itt, iser_ctask->iser_conn);
+ return -EINVAL;
+ }
+
+ err = iser_reg_rdma_mem(iser_ctask,ISER_DIR_IN);
+ if (err) {
+ iser_err("Failed to set up Data-IN RDMA\n");
+ return err;
+ }
+ regd_buf = &iser_ctask->rdma_regd[ISER_DIR_IN];
+
+ hdr->flags |= ISER_RSV;
+ hdr->read_stag = cpu_to_be32(regd_buf->reg.rkey);
+ hdr->read_va = cpu_to_be64(regd_buf->reg.va);
+
+ iser_dbg("Cmd itt:%d READ tags RKEY:%#.4X VA:%#llX\n",
+ ctask->itt, regd_buf->reg.rkey,
+ (unsigned long long)regd_buf->reg.va);
+
+ return 0;
+}
+
+/* Register user buffer memory and initialize passive rdma
+ * dto descriptor. Total data size is stored in
+ * ctask->data[ISER_DIR_OUT].data_len
+ */
+static int
+iser_prepare_write_cmd(struct iscsi_cmd_task *ctask,
+ unsigned int imm_sz,
+ unsigned int unsol_sz,
+ unsigned int edtl)
+{
+ struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
+ struct iser_regd_buf *regd_buf;
+ int err;
+ struct iser_dto *send_dto = &iser_ctask->desc.dto;
+ struct iser_hdr *hdr = &iser_ctask->desc.iser_header;
+ struct iser_data_buf *buf_out = &iser_ctask->data[ISER_DIR_OUT];
+
+ err = iser_dma_map_task_data(iser_ctask,
+ buf_out,
+ ISER_DIR_OUT,
+ DMA_TO_DEVICE);
+ if (err)
+ return err;
+
+ if (edtl > iser_ctask->data[ISER_DIR_OUT].data_len) {
+ iser_err("Total data length: %ld, less than EDTL: %d, "
+ "in WRITE cmd BHS itt: %d, conn: 0x%p\n",
+ iser_ctask->data[ISER_DIR_OUT].data_len,
+ edtl, ctask->itt, ctask->conn);
+ return -EINVAL;
+ }
+
+ err = iser_reg_rdma_mem(iser_ctask,ISER_DIR_OUT);
+ if (err != 0) {
+ iser_err("Failed to register write cmd RDMA mem\n");
+ return err;
+ }
+
+ regd_buf = &iser_ctask->rdma_regd[ISER_DIR_OUT];
+
+ if (unsol_sz < edtl) {
+ hdr->flags |= ISER_WSV;
+ hdr->write_stag = cpu_to_be32(regd_buf->reg.rkey);
+ hdr->write_va = cpu_to_be64(regd_buf->reg.va + unsol_sz);
+
+ iser_dbg("Cmd itt:%d, WRITE tags, RKEY:%#.4X "
+ "VA:%#llX + unsol:%d\n",
+ ctask->itt, regd_buf->reg.rkey,
+ (unsigned long long)regd_buf->reg.va, unsol_sz);
+ }
+
+ if (imm_sz > 0) {
+ iser_dbg("Cmd itt:%d, WRITE, adding imm.data sz: %d\n",
+ ctask->itt, imm_sz);
+ iser_dto_add_regd_buff(send_dto,
+ regd_buf,
+ 0,
+ imm_sz);
+ }
+
+ return 0;
+}
+
+/**
+ * iser_post_receive_control - allocates, initializes and posts receive DTO.
+ */
+static int iser_post_receive_control(struct iscsi_conn *conn)
+{
+ struct iscsi_iser_conn *iser_conn = conn->dd_data;
+ struct iser_desc *rx_desc;
+ struct iser_regd_buf *regd_hdr;
+ struct iser_regd_buf *regd_data;
+ struct iser_dto *recv_dto = NULL;
+ struct iser_device *device = iser_conn->ib_conn->device;
+ int rx_data_size, err = 0;
+
+ rx_desc = kmem_cache_alloc(ig.desc_cache, GFP_KERNEL);
+ if (rx_desc == NULL) {
+ iser_err("Failed to alloc desc for post recv\n");
+ return -ENOMEM;
+ }
+ rx_desc->type = ISCSI_RX;
+
+ /* for the login sequence we must support rx of upto 8K */
+ if (conn->c_stage == ISCSI_CONN_INITIAL_STAGE)
+ rx_data_size = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
+ else /* FIXME till user space sets conn->max_recv_dlength correctly */
+ rx_data_size = 128;
+
+ rx_desc->data = kmalloc(rx_data_size, GFP_KERNEL);
+ if (rx_desc->data == NULL) {
+ iser_err("Failed to alloc data buf for post recv\n");
+ err = -ENOMEM;
+ goto post_rx_kmalloc_failure;
+ }
+
+ recv_dto = &rx_desc->dto;
+ recv_dto->conn = iser_conn;
+ recv_dto->regd_vector_len = 0;
+
+ regd_hdr = &rx_desc->hdr_regd_buf;
+ memset(regd_hdr, 0, sizeof(struct iser_regd_buf));
+ regd_hdr->device = device;
+ regd_hdr->virt_addr = rx_desc; /* == &rx_desc->iser_header */
+ regd_hdr->data_size = ISER_TOTAL_HEADERS_LEN;
+
+ iser_reg_single(device, regd_hdr, DMA_FROM_DEVICE);
+
+ iser_dto_add_regd_buff(recv_dto, regd_hdr, 0, 0);
+
+ regd_data = &rx_desc->data_regd_buf;
+ memset(regd_data, 0, sizeof(struct iser_regd_buf));
+ regd_data->device = device;
+ regd_data->virt_addr = rx_desc->data;
+ regd_data->data_size = rx_data_size;
+
+ iser_reg_single(device, regd_data, DMA_FROM_DEVICE);
+
+ iser_dto_add_regd_buff(recv_dto, regd_data, 0, 0);
+
+ err = iser_post_recv(rx_desc);
+ if (!err)
+ return 0;
+
+ /* iser_post_recv failed */
+ iser_dto_buffs_release(recv_dto);
+ kfree(rx_desc->data);
+post_rx_kmalloc_failure:
+ kmem_cache_free(ig.desc_cache, rx_desc);
+ return err;
+}
+
+/* creates a new tx descriptor and adds header regd buffer */
+static void iser_create_send_desc(struct iscsi_iser_conn *iser_conn,
+ struct iser_desc *tx_desc)
+{
+ struct iser_regd_buf *regd_hdr = &tx_desc->hdr_regd_buf;
+ struct iser_dto *send_dto = &tx_desc->dto;
+
+ memset(regd_hdr, 0, sizeof(struct iser_regd_buf));
+ regd_hdr->device = iser_conn->ib_conn->device;
+ regd_hdr->virt_addr = tx_desc; /* == &tx_desc->iser_header */
+ regd_hdr->data_size = ISER_TOTAL_HEADERS_LEN;
+
+ send_dto->conn = iser_conn;
+ send_dto->notify_enable = 1;
+ send_dto->regd_vector_len = 0;
+
+ memset(&tx_desc->iser_header, 0, sizeof(struct iser_hdr));
+ tx_desc->iser_header.flags = ISER_VER;
+
+ iser_dto_add_regd_buff(send_dto, regd_hdr, 0, 0);
+}
+
+/**
+ * iser_conn_set_full_featured_mode - (iSER API)
+ */
+int iser_conn_set_full_featured_mode(struct iscsi_conn *conn)
+{
+ struct iscsi_iser_conn *iser_conn = conn->dd_data;
+
+ int i;
+ /* no need to keep it in a var, we are after login so if this should
+ * be negotiated, by now the result should be available here */
+ int initial_post_recv_bufs_num = ISER_MAX_RX_MISC_PDUS;
+
+ iser_dbg("Initially post: %d\n", initial_post_recv_bufs_num);
+
+ /* Check that there is no posted recv or send buffers left - */
+ /* they must be consumed during the login phase */
+ BUG_ON(atomic_read(&iser_conn->ib_conn->post_recv_buf_count) != 0);
+ BUG_ON(atomic_read(&iser_conn->ib_conn->post_send_buf_count) != 0);
+
+ /* Initial post receive buffers */
+ for (i = 0; i < initial_post_recv_bufs_num; i++) {
+ if (iser_post_receive_control(conn) != 0) {
+ iser_err("Failed to post recv bufs at:%d conn:0x%p\n",
+ i, conn);
+ return -ENOMEM;
+ }
+ }
+ iser_dbg("Posted %d post recv bufs, conn:0x%p\n", i, conn);
+ return 0;
+}
+
+static int
+iser_check_xmit(struct iscsi_conn *conn, void *task)
+{
+ int rc = 0;
+ struct iscsi_iser_conn *iser_conn = conn->dd_data;
+
+ write_lock_bh(conn->recv_lock);
+ if (atomic_read(&iser_conn->ib_conn->post_send_buf_count) ==
+ ISER_QP_MAX_REQ_DTOS) {
+ iser_dbg("%ld can't xmit task %p, suspending tx\n",jiffies,task);
+ set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+ rc = -EAGAIN;
+ }
+ write_unlock_bh(conn->recv_lock);
+ return rc;
+}
+
+
+/**
+ * iser_send_command - send command PDU
+ */
+int iser_send_command(struct iscsi_conn *conn,
+ struct iscsi_cmd_task *ctask)
+{
+ struct iscsi_iser_conn *iser_conn = conn->dd_data;
+ struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
+ struct iser_dto *send_dto = NULL;
+ unsigned long edtl;
+ int err = 0;
+ struct iser_data_buf *data_buf;
+
+ struct iscsi_cmd *hdr = ctask->hdr;
+ struct scsi_cmnd *sc = ctask->sc;
+
+ if (!iser_conn_state_comp(iser_conn->ib_conn, ISER_CONN_UP)) {
+ iser_err("Failed to send, conn: 0x%p is not up\n", iser_conn->ib_conn);
+ return -EPERM;
+ }
+ if (iser_check_xmit(conn, ctask))
+ return -EAGAIN;
+
+ edtl = ntohl(hdr->data_length);
+
+ /* build the tx desc regd header and add it to the tx desc dto */
+ iser_ctask->desc.type = ISCSI_TX_SCSI_COMMAND;
+ send_dto = &iser_ctask->desc.dto;
+ send_dto->ctask = iser_ctask;
+ iser_create_send_desc(iser_conn, &iser_ctask->desc);
+
+ if (hdr->flags & ISCSI_FLAG_CMD_READ)
+ data_buf = &iser_ctask->data[ISER_DIR_IN];
+ else
+ data_buf = &iser_ctask->data[ISER_DIR_OUT];
+
+ if (sc->use_sg) { /* using a scatter list */
+ data_buf->buf = sc->request_buffer;
+ data_buf->size = sc->use_sg;
+ } else { /* using a single buffer - convert it into one entry SG */
+ sg_init_one(&data_buf->sg_single,
+ sc->request_buffer, sc->request_bufflen);
+ data_buf->buf = &data_buf->sg_single;
+ data_buf->size = 1;
+ }
+
+ data_buf->data_len = sc->request_bufflen;
+
+ if (hdr->flags & ISCSI_FLAG_CMD_READ) {
+ err = iser_prepare_read_cmd(ctask, edtl);
+ if (err)
+ goto send_command_error;
+ }
+ if (hdr->flags & ISCSI_FLAG_CMD_WRITE) {
+ err = iser_prepare_write_cmd(ctask,
+ ctask->imm_count,
+ ctask->imm_count +
+ ctask->unsol_count,
+ edtl);
+ if (err)
+ goto send_command_error;
+ }
+
+ iser_reg_single(iser_conn->ib_conn->device,
+ send_dto->regd[0], DMA_TO_DEVICE);
+
+ if (iser_post_receive_control(conn) != 0) {
+ iser_err("post_recv failed!\n");
+ err = -ENOMEM;
+ goto send_command_error;
+ }
+
+ iser_ctask->status = ISER_TASK_STATUS_STARTED;
+
+ err = iser_post_send(&iser_ctask->desc);
+ if (!err)
+ return 0;
+
+send_command_error:
+ iser_dto_buffs_release(send_dto);
+ iser_err("conn %p failed ctask->itt %d err %d\n",conn, ctask->itt, err);
+ return err;
+}
+
+/**
+ * iser_send_data_out - send data out PDU
+ */
+int iser_send_data_out(struct iscsi_conn *conn,
+ struct iscsi_cmd_task *ctask,
+ struct iscsi_data *hdr)
+{
+ struct iscsi_iser_conn *iser_conn = conn->dd_data;
+ struct iscsi_iser_cmd_task *iser_ctask = ctask->dd_data;
+ struct iser_desc *tx_desc = NULL;
+ struct iser_dto *send_dto = NULL;
+ unsigned long buf_offset;
+ unsigned long data_seg_len;
+ unsigned int itt;
+ int err = 0;
+
+ if (!iser_conn_state_comp(iser_conn->ib_conn, ISER_CONN_UP)) {
+ iser_err("Failed to send, conn: 0x%p is not up\n", iser_conn->ib_conn);
+ return -EPERM;
+ }
+
+ if (iser_check_xmit(conn, ctask))
+ return -EAGAIN;
+
+ itt = ntohl(hdr->itt);
+ data_seg_len = ntoh24(hdr->dlength);
+ buf_offset = ntohl(hdr->offset);
+
+ iser_dbg("%s itt %d dseg_len %d offset %d\n",
+ __func__,(int)itt,(int)data_seg_len,(int)buf_offset);
+
+ tx_desc = kmem_cache_alloc(ig.desc_cache, GFP_KERNEL);
+ if (tx_desc == NULL) {
+ iser_err("Failed to alloc desc for post dataout\n");
+ return -ENOMEM;
+ }
+
+ tx_desc->type = ISCSI_TX_DATAOUT;
+ memcpy(&tx_desc->iscsi_header, hdr, sizeof(struct iscsi_hdr));
+
+ /* build the tx desc regd header and add it to the tx desc dto */
+ send_dto = &tx_desc->dto;
+ send_dto->ctask = iser_ctask;
+ iser_create_send_desc(iser_conn, tx_desc);
+
+ iser_reg_single(iser_conn->ib_conn->device,
+ send_dto->regd[0], DMA_TO_DEVICE);
+
+ /* all data was registered for RDMA, we can use the lkey */
+ iser_dto_add_regd_buff(send_dto,
+ &iser_ctask->rdma_regd[ISER_DIR_OUT],
+ buf_offset,
+ data_seg_len);
+
+ if (buf_offset + data_seg_len > iser_ctask->data[ISER_DIR_OUT].data_len) {
+ iser_err("Offset:%ld & DSL:%ld in Data-Out "
+ "inconsistent with total len:%ld, itt:%d\n",
+ buf_offset, data_seg_len,
+ iser_ctask->data[ISER_DIR_OUT].data_len, itt);
+ err = -EINVAL;
+ goto send_data_out_error;
+ }
+ iser_dbg("data-out itt: %d, offset: %ld, sz: %ld\n",
+ itt, buf_offset, data_seg_len);
+
+
+ err = iser_post_send(tx_desc);
+ if (!err)
+ return 0;
+
+send_data_out_error:
+ iser_dto_buffs_release(send_dto);
+ kmem_cache_free(ig.desc_cache, tx_desc);
+ iser_err("conn %p failed err %d\n",conn, err);
+ return err;
+}
+
+int iser_send_control(struct iscsi_conn *conn,
+ struct iscsi_mgmt_task *mtask)
+{
+ struct iscsi_iser_conn *iser_conn = conn->dd_data;
+ struct iser_desc *mdesc = mtask->dd_data;
+ struct iser_dto *send_dto = NULL;
+ unsigned int itt;
+ unsigned long data_seg_len;
+ int err = 0;
+ unsigned char opcode;
+ struct iser_regd_buf *regd_buf;
+ struct iser_device *device;
+
+ if (!iser_conn_state_comp(iser_conn->ib_conn, ISER_CONN_UP)) {
+ iser_err("Failed to send, conn: 0x%p is not up\n", iser_conn->ib_conn);
+ return -EPERM;
+ }
+
+ if (iser_check_xmit(conn,mtask))
+ return -EAGAIN;
+
+ /* build the tx desc regd header and add it to the tx desc dto */
+ mdesc->type = ISCSI_TX_CONTROL;
+ send_dto = &mdesc->dto;
+ send_dto->ctask = NULL;
+ iser_create_send_desc(iser_conn, mdesc);
+
+ device = iser_conn->ib_conn->device;
+
+ iser_reg_single(device, send_dto->regd[0], DMA_TO_DEVICE);
+
+ itt = ntohl(mtask->hdr->itt);
+ opcode = mtask->hdr->opcode & ISCSI_OPCODE_MASK;
+ data_seg_len = ntoh24(mtask->hdr->dlength);
+
+ if (data_seg_len > 0) {
+ regd_buf = &mdesc->data_regd_buf;
+ memset(regd_buf, 0, sizeof(struct iser_regd_buf));
+ regd_buf->device = device;
+ regd_buf->virt_addr = mtask->data;
+ regd_buf->data_size = mtask->data_count;
+ iser_reg_single(device, regd_buf,
+ DMA_TO_DEVICE);
+ iser_dto_add_regd_buff(send_dto, regd_buf,
+ 0,
+ data_seg_len);
+ }
+
+ if (iser_post_receive_control(conn) != 0) {
+ iser_err("post_rcv_buff failed!\n");
+ err = -ENOMEM;
+ goto send_control_error;
+ }
+
+ err = iser_post_send(mdesc);
+ if (!err)
+ return 0;
+
+send_control_error:
+ iser_dto_buffs_release(send_dto);
+ iser_err("conn %p failed err %d\n",conn, err);
+ return err;
+}
+
+/**
+ * iser_rcv_dto_completion - recv DTO completion
+ */
+void iser_rcv_completion(struct iser_desc *rx_desc,
+ unsigned long dto_xfer_len)
+{
+ struct iser_dto *dto = &rx_desc->dto;
+ struct iscsi_iser_conn *conn = dto->conn;
+ struct iscsi_session *session = conn->iscsi_conn->session;
+ struct iscsi_cmd_task *ctask;
+ struct iscsi_iser_cmd_task *iser_ctask;
+ struct iscsi_hdr *hdr;
+ char *rx_data = NULL;
+ int rx_data_len = 0;
+ unsigned int itt;
+ unsigned char opcode;
+
+ hdr = &rx_desc->iscsi_header;
+
+ iser_dbg("op 0x%x itt 0x%x\n", hdr->opcode,hdr->itt);
+
+ if (dto_xfer_len > ISER_TOTAL_HEADERS_LEN) { /* we have data */
+ rx_data_len = dto_xfer_len - ISER_TOTAL_HEADERS_LEN;
+ rx_data = dto->regd[1]->virt_addr;
+ rx_data += dto->offset[1];
+ }
+
+ opcode = hdr->opcode & ISCSI_OPCODE_MASK;
+
+ if (opcode == ISCSI_OP_SCSI_CMD_RSP) {
+ itt = hdr->itt & ISCSI_ITT_MASK; /* mask out cid and age bits */
+ if (!(itt < session->cmds_max))
+ iser_err("itt can't be matched to task!!!"
+ "conn %p opcode %d cmds_max %d itt %d\n",
+ conn->iscsi_conn,opcode,session->cmds_max,itt);
+ /* use the mapping given with the cmds array indexed by itt */
+ ctask = (struct iscsi_cmd_task *)session->cmds[itt];
+ iser_ctask = ctask->dd_data;
+ iser_dbg("itt %d ctask %p\n",itt,ctask);
+ iser_ctask->status = ISER_TASK_STATUS_COMPLETED;
+ iser_ctask_rdma_finalize(iser_ctask);
+ }
+
+ iser_dto_buffs_release(dto);
+
+ iscsi_iser_recv(conn->iscsi_conn, hdr, rx_data, rx_data_len);
+
+ kfree(rx_desc->data);
+ kmem_cache_free(ig.desc_cache, rx_desc);
+
+ /* decrementing conn->post_recv_buf_count only --after-- freeing the *
+ * task eliminates the need to worry on tasks which are completed in *
+ * parallel to the execution of iser_conn_term. So the code that waits *
+ * for the posted rx bufs refcount to become zero handles everything */
+ atomic_dec(&conn->ib_conn->post_recv_buf_count);
+}
+
+void iser_snd_completion(struct iser_desc *tx_desc)
+{
+ struct iser_dto *dto = &tx_desc->dto;
+ struct iscsi_iser_conn *iser_conn = dto->conn;
+ struct iscsi_conn *conn = iser_conn->iscsi_conn;
+ struct iscsi_mgmt_task *mtask;
+
+ iser_dbg("Initiator, Data sent dto=0x%p\n", dto);
+
+ iser_dto_buffs_release(dto);
+
+ if (tx_desc->type == ISCSI_TX_DATAOUT)
+ kmem_cache_free(ig.desc_cache, tx_desc);
+
+ atomic_dec(&iser_conn->ib_conn->post_send_buf_count);
+
+ write_lock(conn->recv_lock);
+ if (conn->suspend_tx) {
+ iser_dbg("%ld resuming tx\n",jiffies);
+ clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
+ scsi_queue_work(conn->session->host, &conn->xmitwork);
+ }
+ write_unlock(conn->recv_lock);
+
+ if (tx_desc->type == ISCSI_TX_CONTROL) {
+ /* this arithmetic is legal by libiscsi dd_data allocation */
+ mtask = (void *) ((long)(void *)tx_desc -
+ sizeof(struct iscsi_mgmt_task));
+ if (mtask->hdr->itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
+ struct iscsi_session *session = conn->session;
+
+ spin_lock(&conn->session->lock);
+ list_del(&mtask->running);
+ __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
+ sizeof(void*));
+ spin_unlock(&session->lock);
+ }
+ }
+}
+
+void iser_ctask_rdma_init(struct iscsi_iser_cmd_task *iser_ctask)
+
+{
+ iser_ctask->status = ISER_TASK_STATUS_INIT;
+
+ iser_ctask->dir[ISER_DIR_IN] = 0;
+ iser_ctask->dir[ISER_DIR_OUT] = 0;
+
+ iser_ctask->data[ISER_DIR_IN].data_len = 0;
+ iser_ctask->data[ISER_DIR_OUT].data_len = 0;
+
+ memset(&iser_ctask->rdma_regd[ISER_DIR_IN], 0,
+ sizeof(struct iser_regd_buf));
+ memset(&iser_ctask->rdma_regd[ISER_DIR_OUT], 0,
+ sizeof(struct iser_regd_buf));
+}
+
+void iser_ctask_rdma_finalize(struct iscsi_iser_cmd_task *iser_ctask)
+{
+ int deferred;
+
+ /* if we were reading, copy back to unaligned sglist,
+ * anyway dma_unmap and free the copy
+ */
+ if (iser_ctask->data_copy[ISER_DIR_IN].copy_buf != NULL)
+ iser_finalize_rdma_unaligned_sg(iser_ctask, ISER_DIR_IN);
+ if (iser_ctask->data_copy[ISER_DIR_OUT].copy_buf != NULL)
+ iser_finalize_rdma_unaligned_sg(iser_ctask, ISER_DIR_OUT);
+
+ if (iser_ctask->dir[ISER_DIR_IN]) {
+ deferred = iser_regd_buff_release
+ (&iser_ctask->rdma_regd[ISER_DIR_IN]);
+ if (deferred) {
+ iser_err("References remain for BUF-IN rdma reg\n");
+ BUG();
+ }
+ }
+
+ if (iser_ctask->dir[ISER_DIR_OUT]) {
+ deferred = iser_regd_buff_release
+ (&iser_ctask->rdma_regd[ISER_DIR_OUT]);
+ if (deferred) {
+ iser_err("References remain for BUF-OUT rdma reg\n");
+ BUG();
+ }
+ }
+
+ iser_dma_unmap_task_data(iser_ctask);
+}
+
+void iser_dto_buffs_release(struct iser_dto *dto)
+{
+ int i;
+
+ for (i = 0; i < dto->regd_vector_len; i++)
+ iser_regd_buff_release(dto->regd[i]);
+}
+
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