[openib-general] [PATCH v1/RFC] IB: Add SCSI RDMA Protocol (SRP) initiator
Troy Benjegerdes
hozer at hozed.org
Tue Sep 13 14:42:27 PDT 2005
Is there anyplace I can find an SRP target for Linux? What is available?
(Ideally, I'd like one for 2.6.1[3,4] )
On Tue, Sep 13, 2005 at 11:14:55AM -0700, Roland Dreier wrote:
> Sorry to interrupt the SAS arguments, but...
>
> Here's the latest version of the InfiniBand SRP initiator. I think
> it's ready for merging; I implemented error handling, which was the
> main thing pointed out from the generally positive reviews of my
> previous posting. I've done a decent amount of testing without seeing
> any problems, and John Kingman has also tested against his SRP target.
>
> Since this is a completely new driver and can't break anything,
> assuming the code looks good, does it seem OK to merge for 2.6.14?
>
> Thanks,
> Roland
>
>
> Add an InfiniBand SCSI RDMA Protocol (SRP) initiator. This lets us
> talk to InfiniBand SRP targets (storage devices).
>
> Signed-off-by: Roland Dreier <rolandd at cisco.com>
>
> ---
>
> drivers/infiniband/Kconfig | 2
> drivers/infiniband/Makefile | 1
> drivers/infiniband/ulp/srp/Kbuild | 3
> drivers/infiniband/ulp/srp/Kconfig | 11
> drivers/infiniband/ulp/srp/ib_srp.c | 1637 +++++++++++++++++++++++++++++++++++
> drivers/infiniband/ulp/srp/ib_srp.h | 324 +++++++
> 6 files changed, 1978 insertions(+), 0 deletions(-)
>
> 891de9c3d67dc4afc2e5c941bba96613bca81ae1
> diff --git a/drivers/infiniband/Kconfig b/drivers/infiniband/Kconfig
> --- a/drivers/infiniband/Kconfig
> +++ b/drivers/infiniband/Kconfig
> @@ -33,4 +33,6 @@ source "drivers/infiniband/hw/mthca/Kcon
>
> source "drivers/infiniband/ulp/ipoib/Kconfig"
>
> +source "drivers/infiniband/ulp/srp/Kconfig"
> +
> endmenu
> diff --git a/drivers/infiniband/Makefile b/drivers/infiniband/Makefile
> --- a/drivers/infiniband/Makefile
> +++ b/drivers/infiniband/Makefile
> @@ -1,3 +1,4 @@
> obj-$(CONFIG_INFINIBAND) += core/
> obj-$(CONFIG_INFINIBAND_MTHCA) += hw/mthca/
> obj-$(CONFIG_INFINIBAND_IPOIB) += ulp/ipoib/
> +obj-$(CONFIG_INFINIBAND_SRP) += ulp/srp/
> diff --git a/drivers/infiniband/ulp/srp/Kbuild b/drivers/infiniband/ulp/srp/Kbuild
> new file mode 100644
> --- /dev/null
> +++ b/drivers/infiniband/ulp/srp/Kbuild
> @@ -0,0 +1,3 @@
> +EXTRA_CFLAGS += -Idrivers/infiniband/include
> +
> +obj-$(CONFIG_INFINIBAND_SRP) += ib_srp.o
> diff --git a/drivers/infiniband/ulp/srp/Kconfig b/drivers/infiniband/ulp/srp/Kconfig
> new file mode 100644
> --- /dev/null
> +++ b/drivers/infiniband/ulp/srp/Kconfig
> @@ -0,0 +1,11 @@
> +config INFINIBAND_SRP
> + tristate "InfiniBand SCSI RDMA Protocol"
> + depends on INFINIBAND && SCSI
> + ---help---
> + Support for the SCSI RDMA Protocol over InfiniBand. This
> + allows you to access storage devices that speak SRP over
> + InfiniBand.
> +
> + The SRP protocol is defined by the INCITS T10 technical
> + committee. See <http://www.t10.org/>.
> +
> diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
> new file mode 100644
> --- /dev/null
> +++ b/drivers/infiniband/ulp/srp/ib_srp.c
> @@ -0,0 +1,1637 @@
> +/*
> + * Copyright (c) 2005 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: ib_srp.c 3395 2005-09-13 05:10:39Z roland $
> + */
> +
> +#include <linux/version.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/slab.h>
> +#include <linux/err.h>
> +#include <linux/string.h>
> +#include <linux/parser.h>
> +
> +#include <asm/atomic.h>
> +
> +#include <scsi/scsi.h>
> +#include <scsi/scsi_device.h>
> +#include <scsi/scsi_dbg.h>
> +
> +#include <rdma/ib_cache.h>
> +
> +#include "ib_srp.h"
> +
> +#define DRV_NAME "ib_srp"
> +#define PFX DRV_NAME ": "
> +#define DRV_VERSION "0.01"
> +#define DRV_RELDATE "January 11, 2005"
> +
> +MODULE_AUTHOR("Roland Dreier");
> +MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol driver");
> +MODULE_LICENSE("Dual BSD/GPL");
> +
> +static int topspin_workarounds = 1;
> +
> +module_param(topspin_workarounds, int, 0444);
> +MODULE_PARM_DESC(topspin_workarounds,
> + "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
> +
> +static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
> +
> +static void srp_add_one(struct ib_device *device);
> +static void srp_remove_one(struct ib_device *device);
> +static void srp_completion(struct ib_cq *cq, void *target_ptr);
> +static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
> +
> +static struct ib_client srp_client = {
> + .name = "srp",
> + .add = srp_add_one,
> + .remove = srp_remove_one
> +};
> +
> +static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
> +{
> + return (struct srp_target_port *) host->hostdata;
> +}
> +
> +static const char *srp_target_info(struct Scsi_Host *host)
> +{
> + return host_to_target(host)->target_name;
> +}
> +
> +static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
> + unsigned int __nocast gfp_mask,
> + enum dma_data_direction direction)
> +{
> + struct srp_iu *iu;
> +
> + iu = kmalloc(sizeof *iu, gfp_mask);
> + if (!iu)
> + goto out;
> +
> + iu->buf = kzalloc(size, gfp_mask);
> + if (!iu->buf)
> + goto out_free_iu;
> +
> + iu->dma = dma_map_single(host->dev->dma_device, iu->buf, size, direction);
> + if (dma_mapping_error(iu->dma))
> + goto out_free_buf;
> +
> + iu->size = size;
> + iu->direction = direction;
> +
> + return iu;
> +
> +out_free_buf:
> + kfree(iu->buf);
> +out_free_iu:
> + kfree(iu);
> +out:
> + return NULL;
> +}
> +
> +static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
> +{
> + if (!iu)
> + return;
> +
> + dma_unmap_single(host->dev->dma_device, iu->dma, iu->size, iu->direction);
> + kfree(iu->buf);
> + kfree(iu);
> +}
> +
> +static void srp_qp_event(struct ib_event *event, void *context)
> +{
> + printk(KERN_ERR PFX "QP event %d\n", event->event);
> +}
> +
> +static int srp_init_qp(struct srp_target_port *target,
> + struct ib_qp *qp)
> +{
> + struct ib_qp_attr *attr;
> + int ret;
> +
> + attr = kmalloc(sizeof *attr, GFP_KERNEL);
> + if (!attr)
> + return -ENOMEM;
> +
> + ret = ib_find_cached_pkey(target->srp_host->dev,
> + target->srp_host->port,
> + be16_to_cpu(target->path.pkey),
> + &attr->pkey_index);
> + if (ret)
> + return ret;
> +
> + attr->qp_state = IB_QPS_INIT;
> + attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
> + IB_ACCESS_REMOTE_WRITE);
> + attr->port_num = target->srp_host->port;
> +
> + return ib_modify_qp(qp, attr,
> + IB_QP_STATE |
> + IB_QP_PKEY_INDEX |
> + IB_QP_ACCESS_FLAGS |
> + IB_QP_PORT);
> +}
> +
> +static struct ib_qp *srp_create_qp(struct srp_target_port *target,
> + struct ib_qp_init_attr *init_attr)
> +{
> + struct ib_qp *qp;
> + int ret;
> +
> + qp = ib_create_qp(target->srp_host->pd, init_attr);
> + if (IS_ERR(qp))
> + return qp;
> +
> + ret = srp_init_qp(target, qp);
> + if (ret) {
> + ib_destroy_qp(qp);
> + qp = ERR_PTR(ret);
> + }
> +
> + return qp;
> +}
> +
> +static void srp_path_rec_completion(int status,
> + struct ib_sa_path_rec *pathrec,
> + void *target_ptr)
> +{
> + struct srp_target_port *target = target_ptr;
> + struct srp_host *host = target->srp_host;
> + struct ib_qp_init_attr *init_attr = NULL;
> +
> + if (status) {
> + printk(KERN_ERR PFX "Got failed path rec status %d\n", status);
> + target->status = status;
> + goto out;
> + }
> +
> + target->path = *pathrec;
> +
> + /*
> + * We may be getting a path for the second time because we
> + * were redirected to a different port. In that case, there's
> + * no reason to create our CQ and QP again.
> + */
> + if (target->cq) {
> + target->status = 0;
> + goto out;
> + }
> +
> + init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
> + if (!init_attr) {
> + target->status = -ENOMEM;
> + goto out;
> + }
> +
> + target->cq = ib_create_cq(host->dev, srp_completion,
> + NULL, target, SRP_CQ_SIZE);
> + if (IS_ERR(target->cq)) {
> + target->status = PTR_ERR(target->cq);
> + goto out_free;
> + }
> +
> + ib_req_notify_cq(target->cq, IB_CQ_NEXT_COMP);
> +
> + init_attr->event_handler = srp_qp_event;
> + init_attr->cap.max_send_wr = SRP_SQ_SIZE;
> + init_attr->cap.max_recv_wr = SRP_RQ_SIZE;
> + init_attr->cap.max_recv_sge = 1;
> + init_attr->cap.max_send_sge = 1;
> + init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
> + init_attr->qp_type = IB_QPT_RC;
> + init_attr->send_cq = target->cq;
> + init_attr->recv_cq = target->cq;
> +
> + target->qp = srp_create_qp(target, init_attr);
> + if (IS_ERR(target->qp)) {
> + target->status = PTR_ERR(target->qp);
> + ib_destroy_cq(target->cq);
> + goto out_free;
> + }
> +
> + target->status = 0;
> +
> +out_free:
> + kfree(init_attr);
> +
> +out:
> + complete(&target->done);
> +}
> +
> +static int srp_lookup_path(struct srp_target_port *target)
> +{
> + target->path.numb_path = 1;
> +
> + init_completion(&target->done);
> +
> + target->path_query_id = ib_sa_path_rec_get(target->srp_host->dev,
> + target->srp_host->port,
> + &target->path,
> + IB_SA_PATH_REC_DGID |
> + IB_SA_PATH_REC_SGID |
> + IB_SA_PATH_REC_NUMB_PATH |
> + IB_SA_PATH_REC_PKEY,
> + SRP_PATH_REC_TIMEOUT_MS,
> + GFP_KERNEL,
> + srp_path_rec_completion,
> + target, &target->path_query);
> + if (target->path_query_id < 0)
> + return target->path_query_id;
> +
> + wait_for_completion(&target->done);
> +
> + if (target->status < 0)
> + printk(KERN_WARNING PFX "Path record query failed\n");
> +
> + return target->status;
> +}
> +
> +static int srp_send_req(struct srp_target_port *target)
> +{
> + struct {
> + struct ib_cm_req_param param;
> + struct srp_login_req priv;
> + } *req = NULL;
> + int status;
> +
> + req = kzalloc(sizeof *req, GFP_KERNEL);
> + if (!req)
> + return -ENOMEM;
> +
> + req->param.primary_path = &target->path;
> + req->param.alternate_path = NULL;
> + req->param.service_id = target->service_id;
> + req->param.qp_num = target->qp->qp_num;
> + req->param.qp_type = target->qp->qp_type;
> + req->param.starting_psn = 0; /* XXX */
> + req->param.private_data = &req->priv;
> + req->param.private_data_len = sizeof req->priv;
> + req->param.responder_resources = 4;
> + req->param.remote_cm_response_timeout = 20;
> + req->param.flow_control = 1;
> + req->param.local_cm_response_timeout = 20;
> + req->param.retry_count = 7;
> + req->param.rnr_retry_count = 7;
> + req->param.max_cm_retries = 15;
> +
> + req->priv.opcode = SRP_LOGIN_REQ;
> + req->priv.tag = 0;
> + req->priv.req_it_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
> + req->priv.req_buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
> + SRP_BUF_FORMAT_INDIRECT);
> + memcpy(req->priv.initiator_port_id, target->srp_host->initiator_port_id, 16);
> + /*
> + * Topspin/Cisco SRP targets will reject our login unless we
> + * zero out the first 8 bytes of our initiator port ID. The
> + * second 8 bytes must be our local node GUID, but we always
> + * use that anyway.
> + */
> + if (topspin_workarounds && !memcmp(&target->ioc_guid, topspin_oui, 3)) {
> + printk(KERN_DEBUG PFX "Topspin/Cisco initiator port ID workaround "
> + "activated for target GUID %016llx\n",
> + (unsigned long long) be64_to_cpu(target->ioc_guid));
> + memset(req->priv.initiator_port_id, 0, 8);
> + }
> + memcpy(req->priv.target_port_id, &target->id_ext, 8);
> + memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
> +
> + status = ib_send_cm_req(target->cm_id, &req->param);
> + if (status) {
> + ib_destroy_qp(target->qp);
> + ib_destroy_cq(target->cq);
> + }
> +
> + return status;
> +}
> +
> +static void srp_disconnect_target(struct srp_target_port *target)
> +{
> + /* XXX should send SRP_I_LOGOUT request */
> +
> + init_completion(&target->done);
> + ib_send_cm_dreq(target->cm_id, NULL, 0);
> + wait_for_completion(&target->done);
> +}
> +
> +static void srp_free_target_ib(struct srp_target_port *target)
> +{
> + int i;
> +
> + ib_destroy_qp(target->qp);
> + ib_destroy_cq(target->cq);
> +
> + for (i = 0; i < SRP_RQ_SIZE; ++i)
> + srp_free_iu(target->srp_host, target->rx_ring[i]);
> + for (i = 0; i < SRP_SQ_SIZE + 1; ++i)
> + srp_free_iu(target->srp_host, target->tx_ring[i]);
> +}
> +
> +static void srp_remove_work(void *target_ptr)
> +{
> + struct srp_target_port *target = target_ptr;
> +
> + spin_lock_irq(target->scsi_host->host_lock);
> + if (target->state != SRP_TARGET_DEAD) {
> + spin_unlock_irq(target->scsi_host->host_lock);
> + scsi_host_put(target->scsi_host);
> + return;
> + }
> + target->state = SRP_TARGET_REMOVED;
> + spin_unlock_irq(target->scsi_host->host_lock);
> +
> + down(&target->srp_host->target_mutex);
> + list_del(&target->list);
> + up(&target->srp_host->target_mutex);
> +
> + scsi_remove_host(target->scsi_host);
> + ib_destroy_cm_id(target->cm_id);
> + srp_free_target_ib(target);
> + scsi_host_put(target->scsi_host);
> + /* And another put to really free the target port... */
> + scsi_host_put(target->scsi_host);
> +}
> +
> +static int srp_connect_target(struct srp_target_port *target)
> +{
> + int ret;
> +
> + while (1) {
> + init_completion(&target->done);
> + ret = srp_send_req(target);
> + if (ret)
> + return ret;
> + wait_for_completion(&target->done);
> +
> + /*
> + * The CM event handling code will set status to
> + * SRP_PORT_REDIRECT if we get a port redirect REJ
> + * back, or SRP_DLID_REDIRECT if we get a lid/qp
> + * redirect REJ back.
> + */
> + switch (target->status) {
> + case 0:
> + return 0;
> +
> + case SRP_PORT_REDIRECT:
> + ret = srp_lookup_path(target);
> + if (ret)
> + return ret;
> + break;
> +
> + case SRP_DLID_REDIRECT:
> + break;
> +
> + default:
> + return target->status;
> + }
> + }
> +}
> +
> +static int srp_reconnect_target(struct srp_target_port *target)
> +{
> + struct ib_qp_attr qp_attr;
> + struct srp_request *req;
> + struct ib_wc wc;
> + u32 remote_cm_qpn;
> + int ret;
> + int i;
> +
> + spin_lock_irq(target->scsi_host->host_lock);
> + if (target->state != SRP_TARGET_LIVE) {
> + spin_unlock_irq(target->scsi_host->host_lock);
> + return -EAGAIN;
> + }
> + target->state = SRP_TARGET_CONNECTING;
> + spin_unlock_irq(target->scsi_host->host_lock);
> +
> + remote_cm_qpn = target->cm_id->remote_cm_qpn;
> +
> + srp_disconnect_target(target);
> +
> + target->cm_id = ib_create_cm_id(srp_cm_handler, target);
> + if (IS_ERR(target->cm_id)) {
> + ret = PTR_ERR(target->cm_id);
> + target->cm_id = NULL;
> + goto err;
> + }
> +
> + target->cm_id->remote_cm_qpn = remote_cm_qpn;
> +
> + qp_attr.qp_state = IB_QPS_RESET;
> + ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
> + if (ret)
> + goto err;
> +
> + ret = srp_init_qp(target, target->qp);
> + if (ret)
> + goto err;
> +
> + while (ib_poll_cq(target->cq, 1, &wc) > 0)
> + ; /* nothing */
> +
> + list_for_each_entry(req, &target->req_queue, list) {
> + req->scmnd->result = DID_RESET << 16;
> + req->scmnd->scsi_done(req->scmnd);
> + }
> +
> + target->rx_head = 0;
> + target->rx_tail = 0;
> + target->tx_head = 0;
> + target->tx_tail = 0;
> + target->req_head = 0;
> + for (i = 0; i < SRP_SQ_SIZE - 1; ++i)
> + target->req_ring[i].next = i + 1;
> + target->req_ring[SRP_SQ_SIZE - 1].next = -1;
> + INIT_LIST_HEAD(&target->req_queue);
> +
> + ret = srp_connect_target(target);
> + if (ret)
> + goto err;
> +
> + spin_lock_irq(target->scsi_host->host_lock);
> + if (target->state == SRP_TARGET_CONNECTING) {
> + ret = 0;
> + target->state = SRP_TARGET_LIVE;
> + } else
> + ret = -EAGAIN;
> + spin_unlock_irq(target->scsi_host->host_lock);
> +
> + return ret;
> +
> +err:
> + printk(KERN_ERR PFX "reconnect failed, removing target port.\n");
> +
> + /*
> + * We couldn't reconnect, so kill our target port off.
> + * However, we have to defer the real removal because we might
> + * be in the context of the SCSI error handler now, which
> + * would deadlock if we call scsi_remove_host().
> + */
> + spin_lock_irq(target->scsi_host->host_lock);
> + if (target->state == SRP_TARGET_CONNECTING) {
> + target->state = SRP_TARGET_DEAD;
> + INIT_WORK(&target->work, srp_remove_work, target);
> + schedule_work(&target->work);
> + }
> + spin_unlock_irq(target->scsi_host->host_lock);
> +
> + return ret;
> +}
> +
> +static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
> + struct srp_iu *iu)
> +{
> + struct srp_cmd *cmd = iu->buf;
> + int len;
> + u8 fmt;
> +
> + if (!scmnd->request_buffer || scmnd->sc_data_direction == DMA_NONE)
> + return sizeof (struct srp_cmd);
> +
> + if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
> + scmnd->sc_data_direction != DMA_TO_DEVICE) {
> + printk(KERN_WARNING PFX "Unhandled data direction %d\n",
> + scmnd->sc_data_direction);
> + return -EINVAL;
> + }
> +
> + if (scmnd->use_sg) {
> + struct scatterlist *scat = scmnd->request_buffer;
> + int n;
> + int i;
> +
> + n = dma_map_sg(target->srp_host->dev->dma_device,
> + scat, scmnd->use_sg, scmnd->sc_data_direction);
> +
> + if (n == 1) {
> + struct srp_direct_buf *buf = (void *) cmd->add_data;
> +
> + fmt = SRP_DATA_DESC_DIRECT;
> +
> + buf->va = cpu_to_be64(sg_dma_address(scat));
> + buf->key = cpu_to_be32(target->srp_host->mr->rkey);
> + buf->len = cpu_to_be32(sg_dma_len(scat));
> +
> + len = sizeof (struct srp_cmd) +
> + sizeof (struct srp_direct_buf);
> + } else {
> + struct srp_indirect_buf *buf = (void *) cmd->add_data;
> + u32 datalen = 0;
> +
> + fmt = SRP_DATA_DESC_INDIRECT;
> +
> + if (scmnd->sc_data_direction == DMA_TO_DEVICE)
> + cmd->data_out_desc_cnt = n;
> + else
> + cmd->data_in_desc_cnt = n;
> +
> + buf->table_desc.va = cpu_to_be64(iu->dma +
> + sizeof *cmd +
> + sizeof *buf);
> + buf->table_desc.key =
> + cpu_to_be32(target->srp_host->mr->rkey);
> + buf->table_desc.len =
> + cpu_to_be32(n * sizeof (struct srp_direct_buf));
> +
> + for (i = 0; i < n; ++i) {
> + buf->desc_list[i].va = cpu_to_be64(sg_dma_address(&scat[i]));
> + buf->desc_list[i].key =
> + cpu_to_be32(target->srp_host->mr->rkey);
> + buf->desc_list[i].len = cpu_to_be32(sg_dma_len(&scat[i]));
> +
> + datalen += sg_dma_len(&scat[i]);
> + }
> +
> + buf->len = cpu_to_be32(datalen);
> +
> + len = sizeof (struct srp_cmd) +
> + sizeof (struct srp_indirect_buf) +
> + n * sizeof (struct srp_direct_buf);
> + }
> + } else {
> + struct srp_direct_buf *buf = (void *) cmd->add_data;
> + dma_addr_t dma;
> +
> + dma = dma_map_single(target->srp_host->dev->dma_device,
> + scmnd->request_buffer, scmnd->request_bufflen,
> + scmnd->sc_data_direction);
> + if (dma_mapping_error(dma)) {
> + printk(KERN_WARNING PFX "unable to map %p/%d (dir %d)\n",
> + scmnd->request_buffer, (int) scmnd->request_bufflen,
> + scmnd->sc_data_direction);
> + return -EINVAL;
> + }
> +
> + buf->va = cpu_to_be64(dma);
> + buf->key = cpu_to_be32(target->srp_host->mr->rkey);
> + buf->len = cpu_to_be32(scmnd->request_bufflen);
> +
> + fmt = SRP_DATA_DESC_DIRECT;
> +
> + len = sizeof (struct srp_cmd) + sizeof (struct srp_direct_buf);
> + }
> +
> + if (scmnd->sc_data_direction == DMA_TO_DEVICE)
> + cmd->buf_fmt = fmt << 4;
> + else
> + cmd->buf_fmt = fmt;
> +
> +
> + return len;
> +}
> +
> +static void srp_unmap_data(struct scsi_cmnd *scmnd,
> + struct srp_target_port *target,
> + struct srp_cmd *cmd)
> +{
> + if (!scmnd->request_buffer ||
> + (scmnd->sc_data_direction != DMA_TO_DEVICE &&
> + scmnd->sc_data_direction != DMA_FROM_DEVICE))
> + return;
> +
> + if (scmnd->use_sg)
> + dma_unmap_sg(target->srp_host->dev->dma_device,
> + (struct scatterlist *) scmnd->request_buffer,
> + scmnd->use_sg, scmnd->sc_data_direction);
> + else
> + dma_unmap_single(target->srp_host->dev->dma_device,
> + be64_to_cpu(((struct srp_direct_buf *) cmd->add_data)->va),
> + scmnd->request_bufflen,
> + scmnd->sc_data_direction);
> +}
> +
> +static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
> +{
> + struct srp_request *req;
> + struct scsi_cmnd *scmnd;
> + struct srp_iu *iu;
> + unsigned long flags;
> + s32 delta;
> +
> + delta = (s32) be32_to_cpu(rsp->req_lim_delta);
> +
> + spin_lock_irqsave(target->scsi_host->host_lock, flags);
> +
> + target->req_lim += delta;
> +
> + req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
> +
> + if (rsp->tag & SRP_TAG_TSK_MGMT) {
> + if (be32_to_cpu(rsp->resp_data_len) < 4)
> + req->tsk_status = -1;
> + else
> + req->tsk_status = rsp->data[3];
> + complete(&req->done);
> + } else {
> + iu = req->cmd;
> + scmnd = req->scmnd;
> + scmnd->result = rsp->status;
> +
> + if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
> + memcpy(scmnd->sense_buffer, rsp->data +
> + be32_to_cpu(rsp->resp_data_len),
> + min_t(int, be32_to_cpu(rsp->sense_data_len),
> + SCSI_SENSE_BUFFERSIZE));
> + }
> +
> + if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
> + scmnd->resid = be32_to_cpu(rsp->data_out_res_cnt);
> + else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
> + scmnd->resid = be32_to_cpu(rsp->data_in_res_cnt);
> +
> + srp_unmap_data(scmnd, target, iu->buf);
> +
> + if (!req->tsk_mgmt) {
> + req->scmnd = NULL;
> + scmnd->host_scribble = (void *) -1L;
> + scmnd->scsi_done(scmnd);
> +
> + list_del(&req->list);
> + req->next = target->req_head;
> + target->req_head = rsp->tag & ~SRP_TAG_TSK_MGMT;
> + } else
> + req->cmd_done = 1;
> + }
> +
> + spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
> +}
> +
> +static void srp_reconnect_work(void *target_ptr)
> +{
> + struct srp_target_port *target = target_ptr;
> +
> + srp_reconnect_target(target);
> +}
> +
> +static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
> +{
> + struct srp_iu *iu;
> + u8 opcode;
> +
> + iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
> +
> + dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
> + target->max_ti_iu_len, DMA_FROM_DEVICE);
> +
> + opcode = *(u8 *) iu->buf;
> +
> + if (0) {
> + int i;
> +
> + printk(KERN_ERR PFX "recv completion, opcode 0x%02x\n", opcode);
> +
> + for (i = 0; i < wc->byte_len; ++i) {
> + if (i % 8 == 0)
> + printk(KERN_ERR " [%02x] ", i);
> + printk(" %02x", ((u8 *) iu->buf)[i]);
> + if ((i + 1) % 8 == 0)
> + printk("\n");
> + }
> +
> + if (wc->byte_len % 8)
> + printk("\n");
> + }
> +
> + switch (opcode) {
> + case SRP_RSP:
> + srp_process_rsp(target, iu->buf);
> + break;
> +
> + case SRP_T_LOGOUT:
> + /* XXX Handle target logout */
> + printk(KERN_WARNING PFX "Got target logout request\n");
> + break;
> +
> + default:
> + printk(KERN_WARNING PFX "Unhandled SRP opcode 0x%02x\n", opcode);
> + break;
> + }
> +
> + dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
> + target->max_ti_iu_len, DMA_FROM_DEVICE);
> +
> + ++target->rx_tail;
> +}
> +
> +static void srp_completion(struct ib_cq *cq, void *target_ptr)
> +{
> + struct srp_target_port *target = target_ptr;
> + struct ib_wc wc;
> + unsigned long flags;
> +
> + ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
> + while (ib_poll_cq(cq, 1, &wc) > 0) {
> + if (wc.status) {
> + printk(KERN_ERR PFX "failed %s status %d\n",
> + wc.wr_id & SRP_OP_RECV ? "receive" : "send",
> + wc.status);
> + spin_lock_irqsave(target->scsi_host->host_lock, flags);
> + if (target->state == SRP_TARGET_LIVE)
> + schedule_work(&target->work);
> + spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
> + break;
> + }
> +
> + if (wc.wr_id & SRP_OP_RECV)
> + srp_handle_recv(target, &wc);
> + else
> + ++target->tx_tail;
> + }
> +}
> +
> +static int __srp_post_recv(struct srp_target_port *target,
> + unsigned int __nocast gfp_mask)
> +{
> + struct srp_iu *iu;
> + struct ib_sge list;
> + struct ib_recv_wr wr, *bad_wr;
> + unsigned int next;
> + int ret;
> +
> + next = target->rx_head & (SRP_RQ_SIZE - 1);
> + wr.wr_id = next | SRP_OP_RECV;
> + iu = target->rx_ring[next];
> +
> + list.addr = iu->dma;
> + list.length = iu->size;
> + list.lkey = target->srp_host->mr->lkey;
> +
> + wr.next = NULL;
> + wr.sg_list = &list;
> + wr.num_sge = 1;
> +
> + ret = ib_post_recv(target->qp, &wr, &bad_wr);
> + if (!ret)
> + ++target->rx_head;
> +
> + return ret;
> +}
> +
> +static int srp_post_recv(struct srp_target_port *target,
> + unsigned int __nocast gfp_mask)
> +{
> + unsigned long flags;
> + int ret;
> +
> + spin_lock_irqsave(target->scsi_host->host_lock, flags);
> + ret = __srp_post_recv(target, gfp_mask);
> + spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
> +
> + return ret;
> +}
> +
> +/*
> + * Must be called with target->scsi_host->host_lock held to protect
> + * req_lim and tx_head.
> + */
> +static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target)
> +{
> + if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
> + return NULL;
> +
> + return target->tx_ring[target->tx_head & SRP_SQ_SIZE];
> +}
> +
> +/*
> + * Must be called with target->scsi_host->host_lock held to protect
> + * req_lim and tx_head.
> + */
> +static int __srp_post_send(struct srp_target_port *target,
> + struct srp_iu *iu, int len)
> +{
> + struct ib_sge list;
> + struct ib_send_wr wr, *bad_wr;
> + int ret = 0;
> +
> + if (target->req_lim < 1) {
> + printk(KERN_ERR PFX "Target has req_lim %d\n", target->req_lim);
> + return -EAGAIN;
> + }
> +
> + list.addr = iu->dma;
> + list.length = len;
> + list.lkey = target->srp_host->mr->lkey;
> +
> + wr.next = NULL;
> + wr.wr_id = target->tx_head & SRP_SQ_SIZE;
> + wr.sg_list = &list;
> + wr.num_sge = 1;
> + wr.opcode = IB_WR_SEND;
> + wr.send_flags = IB_SEND_SIGNALED;
> +
> + ret = ib_post_send(target->qp, &wr, &bad_wr);
> +
> + if (!ret) {
> + ++target->tx_head;
> + --target->req_lim;
> + }
> +
> + return ret;
> +}
> +
> +static int srp_queuecommand(struct scsi_cmnd *scmnd,
> + void (*done)(struct scsi_cmnd *))
> +{
> + struct srp_target_port *target = host_to_target(scmnd->device->host);
> + struct srp_request *req;
> + struct srp_iu *iu;
> + struct srp_cmd *cmd;
> + long req_index;
> + int len;
> +
> + if (target->state == SRP_TARGET_CONNECTING)
> + goto err;
> +
> + if (target->state == SRP_TARGET_DEAD ||
> + target->state == SRP_TARGET_REMOVED) {
> + scmnd->result = DID_BAD_TARGET << 16;
> + done(scmnd);
> + return 0;
> + }
> +
> + iu = __srp_get_tx_iu(target);
> + if (!iu)
> + goto err;
> +
> + dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
> + SRP_MAX_IU_LEN, DMA_TO_DEVICE);
> +
> + req_index = target->req_head;
> +
> + scmnd->scsi_done = done;
> + scmnd->result = 0;
> + scmnd->host_scribble = (void *) req_index;
> +
> + cmd = iu->buf;
> + memset(cmd, 0, sizeof *cmd);
> +
> + cmd->opcode = SRP_CMD;
> + cmd->lun = cpu_to_be64((u64) scmnd->device->lun << 48);
> + cmd->tag = req_index;
> + memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
> +
> + req = &target->req_ring[req_index];
> +
> + req->scmnd = scmnd;
> + req->cmd = iu;
> + req->cmd_done = 0;
> + req->tsk_mgmt = NULL;
> +
> + len = srp_map_data(scmnd, target, iu);
> + if (len < 0) {
> + printk(KERN_ERR PFX "Failed to map data\n");
> + goto err;
> + }
> +
> + if (__srp_post_recv(target, GFP_ATOMIC)) {
> + printk(KERN_ERR PFX "Recv failed\n");
> + goto err_unmap;
> + }
> +
> + dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
> + SRP_MAX_IU_LEN, DMA_TO_DEVICE);
> +
> + if (__srp_post_send(target, iu, len)) {
> + printk(KERN_ERR PFX "Send failed\n");
> + goto err_unmap;
> + }
> +
> + target->req_head = req->next;
> + list_add_tail(&req->list, &target->req_queue);
> +
> + return 0;
> +
> +err_unmap:
> + srp_unmap_data(scmnd, target, cmd);
> +
> +err:
> + return SCSI_MLQUEUE_HOST_BUSY;
> +}
> +
> +static int srp_alloc_iu_bufs(struct srp_target_port *target)
> +{
> + int i;
> +
> + for (i = 0; i < SRP_RQ_SIZE; ++i) {
> + target->rx_ring[i] = srp_alloc_iu(target->srp_host,
> + target->max_ti_iu_len,
> + GFP_KERNEL, DMA_FROM_DEVICE);
> + if (!target->rx_ring[i])
> + goto err;
> + }
> +
> + for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
> + target->tx_ring[i] = srp_alloc_iu(target->srp_host,
> + SRP_MAX_IU_LEN,
> + GFP_KERNEL, DMA_TO_DEVICE);
> + if (!target->tx_ring[i])
> + goto err;
> + }
> +
> + return 0;
> +
> +err:
> + for (i = 0; i < SRP_RQ_SIZE; ++i) {
> + srp_free_iu(target->srp_host, target->rx_ring[i]);
> + target->rx_ring[i] = NULL;
> + }
> +
> + for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
> + srp_free_iu(target->srp_host, target->tx_ring[i]);
> + target->tx_ring[i] = NULL;
> + }
> +
> + return -ENOMEM;
> +}
> +
> +static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
> +{
> + struct srp_target_port *target = cm_id->context;
> + struct ib_class_port_info *cpi;
> + struct ib_qp_attr *qp_attr = NULL;
> + int attr_mask = 0;
> + int comp = 0;
> + int ret = 0;
> +
> + switch (event->event) {
> + case IB_CM_REQ_ERROR:
> + printk(KERN_DEBUG PFX "Sending CM REQ failed\n");
> + comp = 1;
> + target->status = -ECONNRESET;
> + break;
> +
> + case IB_CM_REP_RECEIVED:
> + comp = 1;
> +
> + {
> + struct srp_login_rsp *rsp = event->private_data;
> +
> + /* XXX check that opcode is SRP RSP */
> +
> + target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
> + target->req_lim = be32_to_cpu(rsp->req_lim_delta);
> +
> + target->scsi_host->can_queue = min(target->req_lim,
> + target->scsi_host->can_queue);
> + }
> +
> + target->status = srp_alloc_iu_bufs(target);
> + if (target->status)
> + break;
> +
> + qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
> + if (!qp_attr) {
> + target->status = -ENOMEM;
> + break;
> + }
> +
> + qp_attr->qp_state = IB_QPS_RTR;
> + target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
> + if (target->status)
> + break;
> +
> + qp_attr->rq_psn = 0; /* XXX */
> + attr_mask |= IB_QP_RQ_PSN;
> +
> + target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
> + if (target->status)
> + break;
> +
> + target->status = srp_post_recv(target, GFP_KERNEL);
> + if (target->status)
> + break;
> +
> + qp_attr->qp_state = IB_QPS_RTS;
> + target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
> + if (target->status)
> + break;
> +
> + target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
> + if (target->status)
> + break;
> +
> + target->status = ib_send_cm_rtu(cm_id, NULL, 0);
> + if (target->status)
> + break;
> +
> + break;
> +
> + case IB_CM_REJ_RECEIVED:
> + printk(KERN_DEBUG PFX "REJ received\n");
> + comp = 1;
> +
> + if (event->param.rej_rcvd.reason == IB_CM_REJ_PORT_CM_REDIRECT) {
> + cpi = event->param.rej_rcvd.ari;
> + target->path.dlid = cpi->redirect_lid;
> + target->path.pkey = cpi->redirect_pkey;
> + cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
> + memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
> +
> + target->status = target->path.dlid ?
> + SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
> + } else if (topspin_workarounds &&
> + !memcmp(&target->ioc_guid, topspin_oui, 3) &&
> + event->param.rej_rcvd.reason == IB_CM_REJ_PORT_REDIRECT) {
> + /*
> + * Topspin/Cisco SRP gateways incorrectly send
> + * reject reason code 25 when they mean 24
> + * (port redirect).
> + */
> + memcpy(target->path.dgid.raw,
> + event->param.rej_rcvd.ari, 16);
> +
> + printk(KERN_DEBUG PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
> + (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
> + (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
> +
> + target->status = SRP_PORT_REDIRECT;
> + } else {
> + printk(KERN_WARNING " REJ reason 0x%x\n",
> + event->param.rej_rcvd.reason);
> + target->status = -ECONNRESET;
> + ret = 1;
> + }
> +
> + break;
> +
> + case IB_CM_MRA_RECEIVED:
> + printk(KERN_ERR PFX "MRA received\n");
> + break;
> +
> + case IB_CM_DREP_RECEIVED:
> + break;
> +
> + case IB_CM_TIMEWAIT_EXIT:
> + printk(KERN_ERR PFX "connection closed\n");
> +
> + comp = 1;
> + ret = 1;
> + target->status = 0;
> + break;
> +
> + default:
> + printk(KERN_WARNING PFX "Unhandled CM event %d\n", event->event);
> + break;
> + }
> +
> + if (comp)
> + complete(&target->done);
> +
> + kfree(qp_attr);
> +
> + return ret;
> +}
> +
> +static int srp_send_tsk_mgmt(struct scsi_cmnd *scmnd, u8 func)
> +{
> + struct srp_target_port *target = host_to_target(scmnd->device->host);
> + struct srp_request *req;
> + struct srp_iu *iu;
> + struct srp_tsk_mgmt *tsk_mgmt;
> + int req_index;
> + int ret = FAILED;
> +
> + spin_lock_irq(target->scsi_host->host_lock);
> +
> + if (scmnd->host_scribble == (void *) -1L)
> + goto out;
> +
> + req_index = (long) scmnd->host_scribble;
> +
> + req = &target->req_ring[req_index];
> + init_completion(&req->done);
> +
> + iu = __srp_get_tx_iu(target);
> + if (!iu)
> + goto out;
> +
> + tsk_mgmt = iu->buf;
> + memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
> +
> + tsk_mgmt->opcode = SRP_TSK_MGMT;
> + tsk_mgmt->lun = cpu_to_be64((u64) scmnd->device->lun << 48);
> + tsk_mgmt->tag = req_index | SRP_TAG_TSK_MGMT;
> + tsk_mgmt->tsk_mgmt_func = func;
> + tsk_mgmt->task_tag = req_index;
> +
> + if (__srp_post_send(target, iu, sizeof tsk_mgmt))
> + goto out;
> +
> + req->tsk_mgmt = iu;
> +
> + spin_unlock_irq(target->scsi_host->host_lock);
> + if (!wait_for_completion_timeout(&req->done,
> + msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
> + return FAILED;
> + spin_lock_irq(target->scsi_host->host_lock);
> +
> + if (req->cmd_done) {
> + list_del(&req->list);
> + req->next = target->req_head;
> + target->req_head = req_index;
> +
> + scmnd->scsi_done(scmnd);
> + } else if (!req->tsk_status) {
> + scmnd->result = DID_ABORT << 16;
> + ret = SUCCESS;
> + }
> +
> +out:
> + spin_unlock_irq(target->scsi_host->host_lock);
> + return ret;
> +}
> +
> +static int srp_abort(struct scsi_cmnd *scmnd)
> +{
> + printk(KERN_ERR "SRP abort called\n");
> +
> + return srp_send_tsk_mgmt(scmnd, SRP_TSK_ABORT_TASK);
> +}
> +
> +static int srp_reset_device(struct scsi_cmnd *scmnd)
> +{
> + printk(KERN_ERR "SRP reset_device called\n");
> +
> + return srp_send_tsk_mgmt(scmnd, SRP_TSK_LUN_RESET);
> +}
> +
> +static int srp_reset_host(struct scsi_cmnd *scmnd)
> +{
> + struct srp_target_port *target = host_to_target(scmnd->device->host);
> + int ret = FAILED;
> +
> + printk(KERN_ERR PFX "SRP reset_host called\n");
> +
> + if (!srp_reconnect_target(target))
> + ret = SUCCESS;
> +
> + return ret;
> +}
> +
> +static struct scsi_host_template srp_template = {
> + .module = THIS_MODULE,
> + .name = DRV_NAME,
> + .info = srp_target_info,
> + .queuecommand = srp_queuecommand,
> + .eh_abort_handler = srp_abort,
> + .eh_device_reset_handler = srp_reset_device,
> + .eh_host_reset_handler = srp_reset_host,
> + .can_queue = SRP_SQ_SIZE,
> + .this_id = -1,
> + .sg_tablesize = SRP_MAX_INDIRECT,
> + .cmd_per_lun = SRP_SQ_SIZE,
> + .use_clustering = ENABLE_CLUSTERING
> +};
> +
> +static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
> +{
> + sprintf(target->target_name, "SRP.T10:%016llX",
> + (unsigned long long) be64_to_cpu(target->id_ext));
> +
> + if (scsi_add_host(target->scsi_host, host->dev->dma_device))
> + return -ENODEV;
> +
> + down(&host->target_mutex);
> + list_add_tail(&target->list, &host->target_list);
> + up(&host->target_mutex);
> +
> + target->state = SRP_TARGET_LIVE;
> +
> + /* XXX: are we supposed to have a definition of SCAN_WILD_CARD ?? */
> + scsi_scan_target(&target->scsi_host->shost_gendev,
> + 0, target->scsi_id, ~0, 0);
> +
> + return 0;
> +}
> +
> +static void srp_release_class_dev(struct class_device *class_dev)
> +{
> + struct srp_host *host =
> + container_of(class_dev, struct srp_host, class_dev);
> +
> + complete(&host->released);
> +}
> +
> +static struct class srp_class = {
> + .name = "infiniband_srp",
> + .release = srp_release_class_dev
> +};
> +
> +/*
> + * Target ports are added by writing
> + *
> + * id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
> + * pkey=<P_Key>,service_id=<service ID>
> + *
> + * to the add_target sysfs attribute.
> + */
> +enum {
> + SRP_OPT_ERR = 0,
> + SRP_OPT_ID_EXT = 1 << 0,
> + SRP_OPT_IOC_GUID = 1 << 1,
> + SRP_OPT_DGID = 1 << 2,
> + SRP_OPT_PKEY = 1 << 3,
> + SRP_OPT_SERVICE_ID = 1 << 4,
> + SRP_OPT_MAX_SECT = 1 << 5,
> + SRP_OPT_ALL = (SRP_OPT_ID_EXT |
> + SRP_OPT_IOC_GUID |
> + SRP_OPT_DGID |
> + SRP_OPT_PKEY |
> + SRP_OPT_SERVICE_ID),
> +};
> +
> +static match_table_t srp_opt_tokens = {
> + { SRP_OPT_ID_EXT, "id_ext=%s" },
> + { SRP_OPT_IOC_GUID, "ioc_guid=%s" },
> + { SRP_OPT_DGID, "dgid=%s" },
> + { SRP_OPT_PKEY, "pkey=%x" },
> + { SRP_OPT_SERVICE_ID, "service_id=%s" },
> + { SRP_OPT_MAX_SECT, "max_sect=%d" },
> + { SRP_OPT_ERR, NULL }
> +};
> +
> +static int srp_parse_options(const char *buf, struct srp_target_port *target)
> +{
> + char *options;
> + char *p;
> + char dgid[3];
> + substring_t args[MAX_OPT_ARGS];
> + int opt_mask = 0;
> + int token;
> + int ret = -EINVAL;
> + int i;
> +
> + options = kstrdup(buf, GFP_KERNEL);
> + if (!options)
> + return -ENOMEM;
> +
> + while ((p = strsep(&options, ",")) != NULL) {
> + if (!*p)
> + continue;
> +
> + token = match_token(p, srp_opt_tokens, args);
> + opt_mask |= token;
> +
> + switch (token) {
> + case SRP_OPT_ID_EXT:
> + p = match_strdup(args);
> + target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
> + kfree(p);
> + break;
> +
> + case SRP_OPT_IOC_GUID:
> + p = match_strdup(args);
> + target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
> + kfree(p);
> + break;
> +
> + case SRP_OPT_DGID:
> + p = match_strdup(args);
> + if (strlen(p) != 32)
> + goto out;
> +
> + for (i = 0; i < 16; ++i) {
> + strlcpy(dgid, p + i * 2, 3);
> + target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
> + }
> + break;
> +
> + case SRP_OPT_PKEY:
> + if (match_hex(args, &token))
> + goto out;
> + target->path.pkey = cpu_to_be16(token);
> + break;
> +
> + case SRP_OPT_SERVICE_ID:
> + p = match_strdup(args);
> + target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
> + kfree(p);
> + break;
> +
> + case SRP_OPT_MAX_SECT:
> + if (match_int(args, &token))
> + goto out;
> + target->scsi_host->max_sectors = token;
> + break;
> +
> + default:
> + goto out;
> + }
> + }
> +
> + if (opt_mask == SRP_OPT_ALL)
> + ret = 0;
> +
> +out:
> + kfree(options);
> + return ret;
> +}
> +
> +static ssize_t srp_create_target(struct class_device *class_dev,
> + const char *buf, size_t count)
> +{
> + struct srp_host *host =
> + container_of(class_dev, struct srp_host, class_dev);
> + struct Scsi_Host *target_host;
> + struct srp_target_port *target;
> + int ret;
> + int i;
> +
> + target_host = scsi_host_alloc(&srp_template,
> + sizeof (struct srp_target_port));
> + if (!target_host)
> + return -ENOMEM;
> +
> + target = host_to_target(target_host);
> + memset(target, 0, sizeof *target);
> +
> + target->scsi_host = target_host;
> + target->srp_host = host;
> +
> + INIT_WORK(&target->work, srp_reconnect_work, target);
> +
> + for (i = 0; i < SRP_SQ_SIZE - 1; ++i)
> + target->req_ring[i].next = i + 1;
> + target->req_ring[SRP_SQ_SIZE - 1].next = -1;
> + INIT_LIST_HEAD(&target->req_queue);
> +
> + ret = srp_parse_options(buf, target);
> + if (ret)
> + goto err;
> +
> + target->cm_id = ib_create_cm_id(srp_cm_handler, target);
> + if (IS_ERR(target->cm_id)) {
> + ret = PTR_ERR(target->cm_id);
> + goto err;
> + }
> +
> + ib_get_cached_gid(host->dev, host->port, 0, &target->path.sgid);
> +
> + printk(KERN_DEBUG PFX "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
> + "service_id %016llx dgid %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
> + (unsigned long long) be64_to_cpu(target->id_ext),
> + (unsigned long long) be64_to_cpu(target->ioc_guid),
> + be16_to_cpu(target->path.pkey),
> + (unsigned long long) be64_to_cpu(target->service_id),
> + (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[0]),
> + (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[2]),
> + (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[4]),
> + (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[6]),
> + (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[8]),
> + (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[10]),
> + (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[12]),
> + (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[14]));
> +
> + ret = srp_lookup_path(target);
> + if (ret) {
> + ib_destroy_cm_id(target->cm_id);
> + goto err;
> + }
> +
> + ret = srp_connect_target(target);
> + if (ret) {
> + printk(KERN_ERR PFX "Connection failed\n");
> + goto err;
> + }
> +
> + ret = srp_add_target(host, target);
> + if (ret)
> + goto err_disconnect;
> +
> + return count;
> +
> +err_disconnect:
> + init_completion(&target->done);
> + ib_send_cm_dreq(target->cm_id, NULL, 0);
> + wait_for_completion(&target->done);
> +
> + ib_destroy_qp(target->qp);
> + ib_destroy_cq(target->cq);
> +
> +err:
> + for (i = 0; i < SRP_RQ_SIZE; ++i)
> + srp_free_iu(target->srp_host, target->rx_ring[i]);
> + for (i = 0; i < SRP_SQ_SIZE + 1; ++i)
> + srp_free_iu(target->srp_host, target->tx_ring[i]);
> +
> + scsi_host_put(target_host);
> +
> + return ret;
> +}
> +
> +static CLASS_DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
> +
> +static struct srp_host *srp_add_port(struct ib_device *device,
> + __be64 node_guid, u8 port)
> +{
> + struct srp_host *host;
> +
> + host = kzalloc(sizeof *host, GFP_KERNEL);
> + if (!host)
> + return NULL;
> +
> + INIT_LIST_HEAD(&host->target_list);
> + init_MUTEX(&host->target_mutex);
> + init_completion(&host->released);
> + host->dev = device;
> + host->port = port;
> +
> + host->initiator_port_id[7] = port;
> + memcpy(host->initiator_port_id + 8, &node_guid, 8);
> +
> + host->pd = ib_alloc_pd(device);
> + if (IS_ERR(host->pd))
> + goto err_free;
> +
> + host->mr = ib_get_dma_mr(host->pd,
> + IB_ACCESS_LOCAL_WRITE |
> + IB_ACCESS_REMOTE_READ |
> + IB_ACCESS_REMOTE_WRITE);
> + if (IS_ERR(host->mr))
> + goto err_pd;
> +
> + host->class_dev.class = &srp_class;
> + host->class_dev.dev = device->dma_device;
> + snprintf(host->class_dev.class_id, BUS_ID_SIZE, "srp-%s-%d",
> + device->name, port);
> +
> + if (class_device_register(&host->class_dev))
> + goto err_mr;
> + if (class_device_create_file(&host->class_dev, &class_device_attr_add_target))
> + goto err_class;
> + /* XXX ibdev / port files as well */
> +
> + return host;
> +
> +err_class:
> + class_device_unregister(&host->class_dev);
> +
> +err_mr:
> + ib_dereg_mr(host->mr);
> +
> +err_pd:
> + ib_dealloc_pd(host->pd);
> +
> +err_free:
> + kfree(host);
> +
> + return NULL;
> +}
> +
> +static void srp_add_one(struct ib_device *device)
> +{
> + struct list_head *dev_list;
> + struct srp_host *host;
> + struct ib_device_attr *dev_attr;
> + int s, e, p;
> +
> + dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
> + if (!dev_attr)
> + return;
> +
> + if (ib_query_device(device, dev_attr)) {
> + printk(KERN_WARNING PFX "Couldn't query node GUID for %s.\n",
> + device->name);
> + goto out;
> + }
> +
> + dev_list = kmalloc(sizeof *dev_list, GFP_KERNEL);
> + if (!dev_list)
> + goto out;
> +
> + INIT_LIST_HEAD(dev_list);
> +
> + if (device->node_type == IB_NODE_SWITCH) {
> + s = 0;
> + e = 0;
> + } else {
> + s = 1;
> + e = device->phys_port_cnt;
> + }
> +
> + for (p = s; p <= e; ++p) {
> + host = srp_add_port(device, dev_attr->node_guid, p);
> + if (host)
> + list_add_tail(&host->list, dev_list);
> + }
> +
> + ib_set_client_data(device, &srp_client, dev_list);
> +
> +out:
> + kfree(dev_attr);
> +}
> +
> +static void srp_remove_one(struct ib_device *device)
> +{
> + struct list_head *dev_list;
> + struct srp_host *host, *tmp_host;
> + LIST_HEAD(target_list);
> + struct srp_target_port *target, *tmp_target;
> + unsigned long flags;
> +
> + dev_list = ib_get_client_data(device, &srp_client);
> +
> + list_for_each_entry_safe(host, tmp_host, dev_list, list) {
> + class_device_unregister(&host->class_dev);
> + /*
> + * Wait for the sysfs entry to go away, so that no new
> + * target ports can be created.
> + */
> + wait_for_completion(&host->released);
> +
> + /*
> + * Mark all target ports as removed, so we stop queueing
> + * commands and don't try to reconnect.
> + */
> + down(&host->target_mutex);
> + list_for_each_entry_safe(target, tmp_target,
> + &host->target_list, list) {
> + spin_lock_irqsave(target->scsi_host->host_lock, flags);
> + if (target->state != SRP_TARGET_REMOVED)
> + target->state = SRP_TARGET_REMOVED;
> + spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
> + }
> + up(&host->target_mutex);
> +
> + /*
> + * Wait for any reconnection tasks that may have
> + * started before we marked our target ports as
> + * removed, and any target port removal tasks.
> + */
> + flush_scheduled_work();
> +
> + list_for_each_entry_safe(target, tmp_target,
> + &host->target_list, list) {
> + scsi_remove_host(target->scsi_host);
> + srp_disconnect_target(target);
> + srp_free_target_ib(target);
> + scsi_host_put(target->scsi_host);
> + }
> +
> + ib_dereg_mr(host->mr);
> + ib_dealloc_pd(host->pd);
> + kfree(host);
> + }
> +
> + kfree(dev_list);
> +}
> +
> +static int __init srp_init_module(void)
> +{
> + int ret;
> +
> + ret = class_register(&srp_class);
> + if (ret) {
> + printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
> + return ret;
> + }
> +
> + ret = ib_register_client(&srp_client);
> + if (ret) {
> + printk(KERN_ERR PFX "couldn't register IB client\n");
> + class_unregister(&srp_class);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void __exit srp_cleanup_module(void)
> +{
> + ib_unregister_client(&srp_client);
> + class_unregister(&srp_class);
> +}
> +
> +module_init(srp_init_module);
> +module_exit(srp_cleanup_module);
> diff --git a/drivers/infiniband/ulp/srp/ib_srp.h b/drivers/infiniband/ulp/srp/ib_srp.h
> new file mode 100644
> --- /dev/null
> +++ b/drivers/infiniband/ulp/srp/ib_srp.h
> @@ -0,0 +1,324 @@
> +/*
> + * Copyright (c) 2005 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: ib_srp.h 3394 2005-09-13 05:04:31Z roland $
> + */
> +
> +#ifndef IB_SRP_H
> +#define IB_SRP_H
> +
> +#include <linux/types.h>
> +#include <linux/list.h>
> +
> +#include <asm/semaphore.h>
> +
> +#include <scsi/scsi_host.h>
> +#include <scsi/scsi_cmnd.h>
> +
> +#include <rdma/ib_verbs.h>
> +#include <rdma/ib_sa.h>
> +#include <rdma/ib_cm.h>
> +
> +enum {
> + SRP_PATH_REC_TIMEOUT_MS = 1000,
> + SRP_ABORT_TIMEOUT_MS = 5000,
> +
> + SRP_PORT_REDIRECT = 1,
> + SRP_DLID_REDIRECT = 2,
> +
> + SRP_MAX_IU_LEN = 256,
> +
> + SRP_RQ_SHIFT = 6,
> + SRP_RQ_SIZE = 1 << SRP_RQ_SHIFT,
> + SRP_SQ_SIZE = SRP_RQ_SIZE - 1,
> + SRP_CQ_SIZE = SRP_SQ_SIZE + SRP_RQ_SIZE,
> +
> + SRP_TAG_TSK_MGMT = 1 << (SRP_RQ_SHIFT + 1)
> +};
> +
> +#define SRP_OP_RECV (1 << 31)
> +#define SRP_MAX_INDIRECT ((SRP_MAX_IU_LEN - \
> + sizeof (struct srp_cmd) - \
> + sizeof (struct srp_indirect_buf)) / 16)
> +
> +enum srp_target_state {
> + SRP_TARGET_LIVE,
> + SRP_TARGET_CONNECTING,
> + SRP_TARGET_DEAD,
> + SRP_TARGET_REMOVED
> +};
> +
> +struct srp_host {
> + u8 initiator_port_id[16];
> + struct ib_device *dev;
> + u8 port;
> + struct ib_pd *pd;
> + struct ib_mr *mr;
> + struct class_device class_dev;
> + struct list_head target_list;
> + struct semaphore target_mutex;
> + struct completion released;
> + struct list_head list;
> +};
> +
> +struct srp_request {
> + struct list_head list;
> + struct scsi_cmnd *scmnd;
> + struct srp_iu *cmd;
> + struct srp_iu *tsk_mgmt;
> + struct completion done;
> + short next;
> + u8 cmd_done;
> + u8 tsk_status;
> +};
> +
> +struct srp_target_port {
> + __be64 id_ext;
> + __be64 ioc_guid;
> + __be64 service_id;
> + struct srp_host *srp_host;
> + struct Scsi_Host *scsi_host;
> + char target_name[32];
> + unsigned int scsi_id;
> +
> + struct ib_sa_path_rec path;
> + struct ib_sa_query *path_query;
> + int path_query_id;
> +
> + struct ib_cm_id *cm_id;
> + struct ib_cq *cq;
> + struct ib_qp *qp;
> +
> + int max_ti_iu_len;
> + s32 req_lim;
> +
> + unsigned rx_head;
> + unsigned rx_tail;
> + struct srp_iu *rx_ring[SRP_RQ_SIZE];
> +
> + unsigned tx_head;
> + unsigned tx_tail;
> + struct srp_iu *tx_ring[SRP_SQ_SIZE + 1];
> +
> + int req_head;
> + struct list_head req_queue;
> + struct srp_request req_ring[SRP_SQ_SIZE];
> +
> + struct work_struct work;
> +
> + struct list_head list;
> + struct completion done;
> + int status;
> + enum srp_target_state state;
> +};
> +
> +struct srp_iu {
> + dma_addr_t dma;
> + void *buf;
> + size_t size;
> + enum dma_data_direction direction;
> +};
> +
> +/*
> + * SRP protocol definitions
> + */
> +
> +enum {
> + SRP_LOGIN_REQ = 0x00,
> + SRP_TSK_MGMT = 0x01,
> + SRP_CMD = 0x02,
> + SRP_I_LOGOUT = 0x03,
> + SRP_LOGIN_RSP = 0xc0,
> + SRP_RSP = 0xc1,
> + SRP_LOGIN_REJ = 0xc2,
> + SRP_T_LOGOUT = 0x80,
> + SRP_CRED_REQ = 0x81,
> + SRP_AER_REQ = 0x82,
> + SRP_CRED_RSP = 0x41,
> + SRP_AER_RSP = 0x42
> +};
> +
> +enum {
> + SRP_BUF_FORMAT_DIRECT = 1 << 1,
> + SRP_BUF_FORMAT_INDIRECT = 1 << 2
> +};
> +
> +enum {
> + SRP_NO_DATA_DESC = 0,
> + SRP_DATA_DESC_DIRECT = 1,
> + SRP_DATA_DESC_INDIRECT = 2
> +};
> +
> +enum {
> + SRP_TSK_ABORT_TASK = 0x01,
> + SRP_TSK_ABORT_TASK_SET = 0x02,
> + SRP_TSK_CLEAR_TASK_SET = 0x04,
> + SRP_TSK_LUN_RESET = 0x08,
> + SRP_TSK_CLEAR_ACA = 0x40
> +};
> +
> +struct srp_direct_buf {
> + __be64 va;
> + __be32 key;
> + __be32 len;
> +};
> +
> +/*
> + * We need the packed attribute because the SRP spec puts the list of
> + * descriptors at an offset of 20, which is not aligned to the size
> + * of struct srp_direct_buf.
> + */
> +struct srp_indirect_buf {
> + struct srp_direct_buf table_desc;
> + __be32 len;
> + struct srp_direct_buf desc_list[0] __attribute__((packed));
> +};
> +
> +enum {
> + SRP_MULTICHAN_SINGLE = 0,
> + SRP_MULTICHAN_MULTI = 1
> +};
> +
> +struct srp_login_req {
> + u8 opcode;
> + u8 reserved1[7];
> + u64 tag;
> + __be32 req_it_iu_len;
> + u8 reserved2[4];
> + __be16 req_buf_fmt;
> + u8 req_flags;
> + u8 reserved3[5];
> + u8 initiator_port_id[16];
> + u8 target_port_id[16];
> +};
> +
> +struct srp_login_rsp {
> + u8 opcode;
> + u8 reserved1[3];
> + __be32 req_lim_delta;
> + u64 tag;
> + __be32 max_it_iu_len;
> + __be32 max_ti_iu_len;
> + __be16 buf_fmt;
> + u8 rsp_flags;
> + u8 reserved2[25];
> +};
> +
> +struct srp_login_rej {
> + u8 opcode;
> + u8 reserved1[3];
> + __be32 reason;
> + u64 tag;
> + u8 reserved2[8];
> + __be16 buf_fmt;
> + u8 reserved3[6];
> +};
> +
> +struct srp_i_logout {
> + u8 opcode;
> + u8 reserved[7];
> + u64 tag;
> +};
> +
> +struct srp_t_logout {
> + u8 opcode;
> + u8 sol_not;
> + u8 reserved[2];
> + __be32 reason;
> + u64 tag;
> +};
> +
> +/*
> + * We need the packed attribute because the SRP spec only aligns the
> + * 8-byte LUN field to 4 bytes.
> + */
> +struct srp_tsk_mgmt {
> + u8 opcode;
> + u8 sol_not;
> + u8 reserved1[6];
> + u64 tag;
> + u8 reserved2[4];
> + __be64 lun __attribute__((packed));
> + u8 reserved3[2];
> + u8 tsk_mgmt_func;
> + u8 reserved4;
> + u64 task_tag;
> + u8 reserved5[8];
> +};
> +
> +/*
> + * We need the packed attribute because the SRP spec only aligns the
> + * 8-byte LUN field to 4 bytes.
> + */
> +struct srp_cmd {
> + u8 opcode;
> + u8 sol_not;
> + u8 reserved1[3];
> + u8 buf_fmt;
> + u8 data_out_desc_cnt;
> + u8 data_in_desc_cnt;
> + u64 tag;
> + u8 reserved2[4];
> + __be64 lun __attribute__((packed));
> + u8 reserved3;
> + u8 task_attr;
> + u8 reserved4;
> + u8 add_cdb_len;
> + u8 cdb[16];
> + u8 add_data[0];
> +};
> +
> +enum {
> + SRP_RSP_FLAG_RSPVALID = 1 << 0,
> + SRP_RSP_FLAG_SNSVALID = 1 << 1,
> + SRP_RSP_FLAG_DOOVER = 1 << 2,
> + SRP_RSP_FLAG_DOUNDER = 1 << 3,
> + SRP_RSP_FLAG_DIOVER = 1 << 4,
> + SRP_RSP_FLAG_DIUNDER = 1 << 5
> +};
> +
> +struct srp_rsp {
> + u8 opcode;
> + u8 sol_not;
> + u8 reserved1[2];
> + __be32 req_lim_delta;
> + u64 tag;
> + u8 reserved2[2];
> + u8 flags;
> + u8 status;
> + __be32 data_out_res_cnt;
> + __be32 data_in_res_cnt;
> + __be32 sense_data_len;
> + __be32 resp_data_len;
> + u8 data[0];
> +};
> +
> +#endif /* IB_SRP_H */
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--
--------------------------------------------------------------------------
Troy Benjegerdes 'da hozer' hozer at hozed.org
Somone asked me why I work on this free (http://www.fsf.org/philosophy/)
software stuff and not get a real job. Charles Shultz had the best answer:
"Why do musicians compose symphonies and poets write poems? They do it
because life wouldn't have any meaning for them if they didn't. That's why
I draw cartoons. It's my life." -- Charles Shultz
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