/*
* Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
* Copyright (c) 2013 Mellanox Technologies. 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.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/scatterlist.h>
#include <linux/kfifo.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_host.h>
#include "iscsi_iser.h"
/* Register user buffer memory and initialize passive rdma
* dto descriptor. Total data size is stored in
* iser_task->data[ISER_DIR_IN].data_len
*/
static int iser_prepare_read_cmd(struct iscsi_task *task,
unsigned int edtl)
{
struct iscsi_iser_task *iser_task = task->dd_data;
struct iser_regd_buf *regd_buf;
int err;
struct iser_hdr *hdr = &iser_task->desc.iser_header;
struct iser_data_buf *buf_in = &iser_task->data[ISER_DIR_IN];
err = iser_dma_map_task_data(iser_task,
buf_in,
ISER_DIR_IN,
DMA_FROM_DEVICE);
if (err)
return err;
if (edtl > iser_task->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_task->data[ISER_DIR_IN].data_len, edtl,
task->itt, iser_task->iser_conn);
return -EINVAL;
}
err = iser_reg_rdma_mem(iser_task,ISER_DIR_IN);
if (err) {
iser_err("Failed to set up Data-IN RDMA\n");
return err;
}
regd_buf = &iser_task->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",
task->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
* task->data[ISER_DIR_OUT].data_len
*/
static int
iser_prepare_write_cmd(struct iscsi_task *task,
unsigned int imm_sz,
unsigned int unsol_sz,
unsigned int edtl)
{
struct iscsi_iser_task *iser_task = task->dd_data;
struct iser_regd_buf *regd_buf;
int err;
struct iser_hdr *hdr = &iser_task->desc.iser_header;
struct iser_data_buf *buf_out = &iser_task->data[ISER_DIR_OUT];
struct ib_sge *tx_dsg = &iser_task->desc.tx_sg[1];
err = iser_dma_map_task_data(iser_task,
buf_out,
ISER_DIR_OUT,
DMA_TO_DEVICE);
if (err)
return err;
if (edtl > iser_task->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_task->data[ISER_DIR_OUT].data_len,
edtl, task->itt, task->conn);
return -EINVAL;
}
err = iser_reg_rdma_mem(iser_task,ISER_DIR_OUT);
if (err != 0) {
iser_err("Failed to register write cmd RDMA mem\n");
return err;
}
regd_buf = &iser_task->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",
task->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",
task->itt, imm_sz);
tx_dsg->addr = regd_buf->reg.va;
tx_dsg->length = imm_sz;
tx_dsg->lkey = regd_buf->reg.lkey;
iser_task->desc.num_sge = 2;
}
return 0;
}
/* creates a new tx descriptor and adds header regd buffer */
static void iser_create_send_desc(struct iser_conn *ib_conn,
struct iser_tx_desc *tx_desc)
{
struct iser_device *device = ib_conn->device;
ib_dma_sync_single_for_cpu(device->ib_device,
tx_desc->dma_addr, ISER_HEADERS_LEN, DMA_TO_DEVICE);
memset(&tx_desc->iser_header, 0, sizeof(struct iser_hdr));
tx_desc->iser_header.flags = ISER_VER;
tx_desc->num_sge = 1;
if (tx_desc->tx_sg[0].lkey != device->mr->lkey) {
tx_desc->tx_sg[0].lkey = device->mr->lkey;
iser_dbg("sdesc %p lkey mismatch, fixing\n", tx_desc);
}
}
int iser_alloc_rx_descriptors(struct iser_conn *ib_conn)
{
int i, j;
u64 dma_addr;
struct iser_rx_desc *rx_desc;
struct ib_sge *rx_sg;
struct iser_device *device = ib_conn->device;
ib_conn->rx_descs = kmalloc(ISER_QP_MAX_RECV_DTOS *
sizeof(struct iser_rx_desc), GFP_KERNEL);
if (!ib_conn->rx_descs)
goto rx_desc_alloc_fail;
rx_desc = ib_conn->rx_descs;
for (i = 0; i < ISER_QP_MAX_RECV_DTOS; i++, rx_desc++) {
dma_addr = ib_dma_map_single(device->ib_device, (void *)rx_desc,
ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
if (ib_dma_mapping_error(device->ib_device, dma_addr))
goto rx_desc_dma_map_failed;
rx_desc->dma_addr = dma_addr;
rx_sg = &rx_desc->rx_sg;
rx_sg->addr = rx_desc->dma_addr;
rx_sg->length = ISER_RX_PAYLOAD_SIZE;
rx_sg->lkey = device->mr->lkey;
}
ib_conn->rx_desc_head = 0;
return 0;
rx_desc_dma_map_failed:
rx_desc = ib_conn->rx_descs;
for (j = 0; j < i; j++, rx_desc++)
ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr,
ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
kfree(ib_conn->rx_descs);
ib_conn->rx_descs = NULL;
rx_desc_alloc_fail:
iser_err("failed allocating rx descriptors / data buffers\n");
return -ENOMEM;
}
void iser_free_rx_descriptors(struct iser_conn *ib_conn)
{
int i;
struct iser_rx_desc *rx_desc;
struct iser_device *device = ib_conn->device;
if (!ib_conn->rx_descs)
return;
rx_desc = ib_conn->rx_descs;
for (i = 0; i < ISER_QP_MAX_RECV_DTOS; i++, rx_desc++)
ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr,
ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
kfree(ib_conn->rx_descs);
}
static int iser_post_rx_bufs(struct iscsi_conn *conn, struct iscsi_hdr *req)
{
struct iscsi_iser_conn *iser_conn = conn->dd_data;
iser_dbg("req op %x flags %x\n", req->opcode, req->flags);
/* check if this is the last login - going to full feature phase */
if ((req->flags & ISCSI_FULL_FEATURE_PHASE) != ISCSI_FULL_FEATURE_PHASE)
return 0;
/*
* Check that there is one posted recv buffer (for the last login
* response) and no posted send buffers left - they must have been
* consumed during previous login phases.
*/
WARN_ON(iser_conn->ib_conn->post_recv_buf_count != 1);
WARN_ON(atomic_read(&iser_conn->ib_conn->post_send_buf_count) != 0);
iser_dbg("Initially post: %d\n", ISER_MIN_POSTED_RX);
/* Initial post receive buffers */
if (iser_post_recvm(iser_conn->ib_conn, ISER_MIN_POSTED_RX))
return -ENOMEM;
return 0;
}
/**
* iser_send_command - send command PDU
*/
int iser_send_command(struct iscsi_conn *conn,
struct iscsi_task *task)
{
struct iscsi_iser_conn *iser_conn = conn->dd_data;
struct iscsi_iser_task *iser_task = task->dd_data;
unsigned long edtl;
int err;
struct iser_data_buf *data_buf;
struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)task->hdr;
struct scsi_cmnd *sc = task->sc;
struct iser_tx_desc *tx_desc = &iser_task->desc;
edtl = ntohl(hdr->data_length);
/* build the tx desc regd header and add it to the tx desc dto */
tx_desc->type = ISCSI_TX_SCSI_COMMAND;
iser_create_send_desc(iser_conn->ib_conn, tx_desc);
if (hdr->flags & ISCSI_FLAG_CMD_READ)
data_buf = &iser_task->data[ISER_DIR_IN];
else
data_buf = &iser_task->data[ISER_DIR_OUT];
if (scsi_sg_count(sc)) { /* using a scatter list */
data_buf->buf = scsi_sglist(sc);
data_buf->size = scsi_sg_count(sc);
}
data_buf->data_len = scsi_bufflen(sc);
if (hdr->flags & ISCSI_FLAG_CMD_READ) {
err = iser_prepare_read_cmd(task, edtl);
if (err)
goto send_command_error;
}
if (hdr->flags & ISCSI_FLAG_CMD_WRITE) {
err = iser_prepare_write_cmd(task,
task->imm_count,
task->imm_count +
task->unsol_r2t.data_length,
edtl);
if (err)
goto send_command_error;
}
iser_task->status = ISER_TASK_STATUS_STARTED;
err = iser_post_send(iser_conn->ib_conn, tx_desc);
if (!err)
return 0;
send_command_error:
iser_err("conn %p failed task->itt %d err %d\n",conn, task->itt, err);
return err;
}
/**
* iser_send_data_out - send data out PDU
*/
int iser_send_data_out(struct iscsi_conn *conn,
struct iscsi_task *task,
struct iscsi_data *hdr)
{
struct iscsi_iser_conn *iser_conn = conn->dd_data;
struct iscsi_iser_task *iser_task = task->dd_data;
struct iser_tx_desc *tx_desc = NULL;
struct iser_regd_buf *regd_buf;
unsigned long buf_offset;
unsigned long data_seg_len;
uint32_t itt;
int err = 0;
struct ib_sge *tx_dsg;
itt = (__force uint32_t)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_zalloc(ig.desc_cache, GFP_ATOMIC);
if (tx_desc == NULL) {
iser_err("Failed to alloc desc for post dataout\n");
return -ENOMEM;
}
tx_desc->type = ISCSI_TX_DATAOUT;
tx_desc->iser_header.flags = ISER_VER;
memcpy(&tx_desc->iscsi_header, hdr, sizeof(struct iscsi_hdr));
/* build the tx desc */
iser_initialize_task_headers(task, tx_desc);
regd_buf = &iser_task->rdma_regd[ISER_DIR_OUT];
tx_dsg = &tx_desc->tx_sg[1];
tx_dsg->addr = regd_buf->reg.va + buf_offset;
tx_dsg->length = data_seg_len;
tx_dsg->lkey = regd_buf->reg.lkey;
tx_desc->num_sge = 2;
if (buf_offset + data_seg_len > iser_task->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_task->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(iser_conn->ib_conn, tx_desc);
if (!err)
return 0;
send_data_out_error:
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_task *task)
{
struct iscsi_iser_conn *iser_conn = conn->dd_data;
struct iscsi_iser_task *iser_task = task->dd_data;
struct iser_tx_desc *mdesc = &iser_task->desc;
unsigned long data_seg_len;
int err = 0;
struct iser_device *device;
struct iser_conn *ib_conn = iser_conn->ib_conn;
/* build the tx desc regd header and add it to the tx desc dto */
mdesc->type = ISCSI_TX_CONTROL;
iser_create_send_desc(iser_conn->ib_conn, mdesc);
device = iser_conn->ib_conn->device;
data_seg_len = ntoh24(task->hdr->dlength);
if (data_seg_len > 0) {
struct ib_sge *tx_dsg = &mdesc->tx_sg[1];
if (task != conn->login_task) {
iser_err("data present on non login task!!!\n");
goto send_control_error;
}
ib_dma_sync_single_for_cpu(device->ib_device,
ib_conn->login_req_dma, task->data_count,
DMA_TO_DEVICE);
memcpy(iser_conn->ib_conn->login_req_buf, task->data,
task->data_count);
ib_dma_sync_single_for_device(device->ib_device,
ib_conn->login_req_dma, task->data_count,
DMA_TO_DEVICE);
tx_dsg->addr = iser_conn->ib_conn->login_req_dma;
tx_dsg->length = task->data_count;
tx_dsg->lkey = device->mr->lkey;
mdesc->num_sge = 2;
}
if (task == conn->login_task) {
err = iser_post_recvl(iser_conn->ib_conn);
if (err)
goto send_control_error;
err = iser_post_rx_bufs(conn, task->hdr);
if (err)
goto send_control_error;
}
err = iser_post_send(iser_conn->ib_conn, mdesc);
if (!err)
return 0;
send_control_error:
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_rx_desc *rx_desc,
unsigned long rx_xfer_len,
struct iser_conn *ib_conn)
{
struct iscsi_iser_conn *conn = ib_conn->iser_conn;
struct iscsi_hdr *hdr;
u64 rx_dma;
int rx_buflen, outstanding, count, err;
/* differentiate between login to all other PDUs */
if ((char *)rx_desc == ib_conn->login_resp_buf) {
rx_dma = ib_conn->login_resp_dma;
rx_buflen = ISER_RX_LOGIN_SIZE;
} else {
rx_dma = rx_desc->dma_addr;
rx_buflen = ISER_RX_PAYLOAD_SIZE;
}
ib_dma_sync_single_for_cpu(ib_conn->device->ib_device, rx_dma,
rx_buflen, DMA_FROM_DEVICE);
hdr = &rx_desc->iscsi_header;
iser_dbg("op 0x%x itt 0x%x dlen %d\n", hdr->opcode,
hdr->itt, (int)(rx_xfer_len - ISER_HEADERS_LEN));
iscsi_iser_recv(conn->iscsi_conn, hdr,
rx_desc->data, rx_xfer_len - ISER_HEADERS_LEN);
ib_dma_sync_single_for_device(ib_conn->device->ib_device, rx_dma,
rx_buflen, DMA_FROM_DEVICE);
/* 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 */
conn->ib_conn->post_recv_buf_count--;
if (rx_dma == ib_conn->login_resp_dma)
return;
outstanding = ib_conn->post_recv_buf_count;
if (outstanding + ISER_MIN_POSTED_RX <= ISER_QP_MAX_RECV_DTOS) {
count = min(ISER_QP_MAX_RECV_DTOS - outstanding,
ISER_MIN_POSTED_RX);
err = iser_post_recvm(ib_conn, count);
if (err)
iser_err("posting %d rx bufs err %d\n", count, err);
}
}
void iser_snd_completion(struct iser_tx_desc *tx_desc,
struct iser_conn *ib_conn)
{
struct iscsi_task *task;
struct iser_device *device = ib_conn->device;
if (tx_desc->type == ISCSI_TX_DATAOUT) {
ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr,
ISER_HEADERS_LEN, DMA_TO_DEVICE);
kmem_cache_free(ig.desc_cache, tx_desc);
}
atomic_dec(&ib_conn->post_send_buf_count);
if (tx_desc->type == ISCSI_TX_CONTROL) {
/* this arithmetic is legal by libiscsi dd_data allocation */
task = (void *) ((long)(void *)tx_desc -
sizeof(struct iscsi_task));
if (task->hdr->itt == RESERVED_ITT)
iscsi_put_task(task);
}
}
void iser_task_rdma_init(struct iscsi_iser_task *iser_task)
{
iser_task->status = ISER_TASK_STATUS_INIT;
iser_task->dir[ISER_DIR_IN] = 0;
iser_task->dir[ISER_DIR_OUT] = 0;
iser_task->data[ISER_DIR_IN].data_len = 0;
iser_task->data[ISER_DIR_OUT].data_len = 0;
memset(&iser_task->rdma_regd[ISER_DIR_IN], 0,
sizeof(struct iser_regd_buf));
memset(&iser_task->rdma_regd[ISER_DIR_OUT], 0,
sizeof(struct iser_regd_buf));
}
void iser_task_rdma_finalize(struct iscsi_iser_task *iser_task)
{
int is_rdma_aligned = 1;
struct iser_regd_buf *regd;
/* if we were reading, copy back to unaligned sglist,
* anyway dma_unmap and free the copy
*/
if (iser_task->data_copy[ISER_DIR_IN].copy_buf != NULL) {
is_rdma_aligned = 0;
iser_finalize_rdma_unaligned_sg(iser_task, ISER_DIR_IN);
}
if (iser_task->data_copy[ISER_DIR_OUT].copy_buf != NULL) {
is_rdma_aligned = 0;
iser_finalize_rdma_unaligned_sg(iser_task, ISER_DIR_OUT);
}
if (iser_task->dir[ISER_DIR_IN]) {
regd = &iser_task->rdma_regd[ISER_DIR_IN];
if (regd->reg.is_fmr)
iser_unreg_mem(®d->reg);
}
if (iser_task->dir[ISER_DIR_OUT]) {
regd = &iser_task->rdma_regd[ISER_DIR_OUT];
if (regd->reg.is_fmr)
iser_unreg_mem(®d->reg);
}
/* if the data was unaligned, it was already unmapped and then copied */
if (is_rdma_aligned)
iser_dma_unmap_task_data(iser_task);
}