ib_srp.c 89.0 KB
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/*
 * 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.
 */

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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#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 <linux/random.h>
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#include <linux/jiffies.h>
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#include <linux/atomic.h>
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#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_dbg.h>
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#include <scsi/scsi_tcq.h>
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#include <scsi/srp.h>
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#include <scsi/scsi_transport_srp.h>
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#include "ib_srp.h"

#define DRV_NAME	"ib_srp"
#define PFX		DRV_NAME ": "
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#define DRV_VERSION	"1.0"
#define DRV_RELDATE	"July 1, 2013"
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MODULE_AUTHOR("Roland Dreier");
MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
		   "v" DRV_VERSION " (" DRV_RELDATE ")");
MODULE_LICENSE("Dual BSD/GPL");

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static unsigned int srp_sg_tablesize;
static unsigned int cmd_sg_entries;
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static unsigned int indirect_sg_entries;
static bool allow_ext_sg;
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static bool prefer_fr;
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static bool register_always;
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static int topspin_workarounds = 1;
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module_param(srp_sg_tablesize, uint, 0444);
MODULE_PARM_DESC(srp_sg_tablesize, "Deprecated name for cmd_sg_entries");
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module_param(cmd_sg_entries, uint, 0444);
MODULE_PARM_DESC(cmd_sg_entries,
		 "Default number of gather/scatter entries in the SRP command (default is 12, max 255)");
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module_param(indirect_sg_entries, uint, 0444);
MODULE_PARM_DESC(indirect_sg_entries,
		 "Default max number of gather/scatter entries (default is 12, max is " __stringify(SCSI_MAX_SG_CHAIN_SEGMENTS) ")");

module_param(allow_ext_sg, bool, 0444);
MODULE_PARM_DESC(allow_ext_sg,
		  "Default behavior when there are more than cmd_sg_entries S/G entries after mapping; fails the request when false (default false)");

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module_param(topspin_workarounds, int, 0444);
MODULE_PARM_DESC(topspin_workarounds,
		 "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");

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module_param(prefer_fr, bool, 0444);
MODULE_PARM_DESC(prefer_fr,
"Whether to use fast registration if both FMR and fast registration are supported");

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module_param(register_always, bool, 0444);
MODULE_PARM_DESC(register_always,
		 "Use memory registration even for contiguous memory regions");

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static struct kernel_param_ops srp_tmo_ops;

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static int srp_reconnect_delay = 10;
module_param_cb(reconnect_delay, &srp_tmo_ops, &srp_reconnect_delay,
		S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(reconnect_delay, "Time between successive reconnect attempts");

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static int srp_fast_io_fail_tmo = 15;
module_param_cb(fast_io_fail_tmo, &srp_tmo_ops, &srp_fast_io_fail_tmo,
		S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(fast_io_fail_tmo,
		 "Number of seconds between the observation of a transport"
		 " layer error and failing all I/O. \"off\" means that this"
		 " functionality is disabled.");

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static int srp_dev_loss_tmo = 600;
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module_param_cb(dev_loss_tmo, &srp_tmo_ops, &srp_dev_loss_tmo,
		S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(dev_loss_tmo,
		 "Maximum number of seconds that the SRP transport should"
		 " insulate transport layer errors. After this time has been"
		 " exceeded the SCSI host is removed. Should be"
		 " between 1 and " __stringify(SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
		 " if fast_io_fail_tmo has not been set. \"off\" means that"
		 " this functionality is disabled.");

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static void srp_add_one(struct ib_device *device);
static void srp_remove_one(struct ib_device *device);
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static void srp_recv_completion(struct ib_cq *cq, void *ch_ptr);
static void srp_send_completion(struct ib_cq *cq, void *ch_ptr);
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static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);

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static struct scsi_transport_template *ib_srp_transport_template;
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static struct workqueue_struct *srp_remove_wq;
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static struct ib_client srp_client = {
	.name   = "srp",
	.add    = srp_add_one,
	.remove = srp_remove_one
};

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static struct ib_sa_client srp_sa_client;

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static int srp_tmo_get(char *buffer, const struct kernel_param *kp)
{
	int tmo = *(int *)kp->arg;

	if (tmo >= 0)
		return sprintf(buffer, "%d", tmo);
	else
		return sprintf(buffer, "off");
}

static int srp_tmo_set(const char *val, const struct kernel_param *kp)
{
	int tmo, res;

	if (strncmp(val, "off", 3) != 0) {
		res = kstrtoint(val, 0, &tmo);
		if (res)
			goto out;
	} else {
		tmo = -1;
	}
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	if (kp->arg == &srp_reconnect_delay)
		res = srp_tmo_valid(tmo, srp_fast_io_fail_tmo,
				    srp_dev_loss_tmo);
	else if (kp->arg == &srp_fast_io_fail_tmo)
		res = srp_tmo_valid(srp_reconnect_delay, tmo, srp_dev_loss_tmo);
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	else
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		res = srp_tmo_valid(srp_reconnect_delay, srp_fast_io_fail_tmo,
				    tmo);
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	if (res)
		goto out;
	*(int *)kp->arg = tmo;

out:
	return res;
}

static struct kernel_param_ops srp_tmo_ops = {
	.get = srp_tmo_get,
	.set = srp_tmo_set,
};

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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;
}

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static int srp_target_is_topspin(struct srp_target_port *target)
{
	static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
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	static const u8 cisco_oui[3]   = { 0x00, 0x1b, 0x0d };
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	return topspin_workarounds &&
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		(!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
		 !memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
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}

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static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
				   gfp_t 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;

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	iu->dma = ib_dma_map_single(host->srp_dev->dev, iu->buf, size,
				    direction);
	if (ib_dma_mapping_error(host->srp_dev->dev, iu->dma))
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		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;

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	ib_dma_unmap_single(host->srp_dev->dev, iu->dma, iu->size,
			    iu->direction);
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	kfree(iu->buf);
	kfree(iu);
}

static void srp_qp_event(struct ib_event *event, void *context)
{
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	pr_debug("QP event %d\n", event->event);
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}

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;

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	ret = ib_find_pkey(target->srp_host->srp_dev->dev,
			   target->srp_host->port,
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			   be16_to_cpu(target->pkey),
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			   &attr->pkey_index);
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	if (ret)
		goto out;

	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;

	ret = ib_modify_qp(qp, attr,
			   IB_QP_STATE		|
			   IB_QP_PKEY_INDEX	|
			   IB_QP_ACCESS_FLAGS	|
			   IB_QP_PORT);

out:
	kfree(attr);
	return ret;
}

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static int srp_new_cm_id(struct srp_rdma_ch *ch)
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{
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	struct srp_target_port *target = ch->target;
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	struct ib_cm_id *new_cm_id;

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	new_cm_id = ib_create_cm_id(target->srp_host->srp_dev->dev,
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				    srp_cm_handler, ch);
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	if (IS_ERR(new_cm_id))
		return PTR_ERR(new_cm_id);

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	if (ch->cm_id)
		ib_destroy_cm_id(ch->cm_id);
	ch->cm_id = new_cm_id;
	ch->path.sgid = target->sgid;
	ch->path.dgid = target->orig_dgid;
	ch->path.pkey = target->pkey;
	ch->path.service_id = target->service_id;
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	return 0;
}

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static struct ib_fmr_pool *srp_alloc_fmr_pool(struct srp_target_port *target)
{
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_fmr_pool_param fmr_param;

	memset(&fmr_param, 0, sizeof(fmr_param));
	fmr_param.pool_size	    = target->scsi_host->can_queue;
	fmr_param.dirty_watermark   = fmr_param.pool_size / 4;
	fmr_param.cache		    = 1;
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	fmr_param.max_pages_per_fmr = dev->max_pages_per_mr;
	fmr_param.page_shift	    = ilog2(dev->mr_page_size);
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	fmr_param.access	    = (IB_ACCESS_LOCAL_WRITE |
				       IB_ACCESS_REMOTE_WRITE |
				       IB_ACCESS_REMOTE_READ);

	return ib_create_fmr_pool(dev->pd, &fmr_param);
}

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/**
 * srp_destroy_fr_pool() - free the resources owned by a pool
 * @pool: Fast registration pool to be destroyed.
 */
static void srp_destroy_fr_pool(struct srp_fr_pool *pool)
{
	int i;
	struct srp_fr_desc *d;

	if (!pool)
		return;

	for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) {
		if (d->frpl)
			ib_free_fast_reg_page_list(d->frpl);
		if (d->mr)
			ib_dereg_mr(d->mr);
	}
	kfree(pool);
}

/**
 * srp_create_fr_pool() - allocate and initialize a pool for fast registration
 * @device:            IB device to allocate fast registration descriptors for.
 * @pd:                Protection domain associated with the FR descriptors.
 * @pool_size:         Number of descriptors to allocate.
 * @max_page_list_len: Maximum fast registration work request page list length.
 */
static struct srp_fr_pool *srp_create_fr_pool(struct ib_device *device,
					      struct ib_pd *pd, int pool_size,
					      int max_page_list_len)
{
	struct srp_fr_pool *pool;
	struct srp_fr_desc *d;
	struct ib_mr *mr;
	struct ib_fast_reg_page_list *frpl;
	int i, ret = -EINVAL;

	if (pool_size <= 0)
		goto err;
	ret = -ENOMEM;
	pool = kzalloc(sizeof(struct srp_fr_pool) +
		       pool_size * sizeof(struct srp_fr_desc), GFP_KERNEL);
	if (!pool)
		goto err;
	pool->size = pool_size;
	pool->max_page_list_len = max_page_list_len;
	spin_lock_init(&pool->lock);
	INIT_LIST_HEAD(&pool->free_list);

	for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) {
		mr = ib_alloc_fast_reg_mr(pd, max_page_list_len);
		if (IS_ERR(mr)) {
			ret = PTR_ERR(mr);
			goto destroy_pool;
		}
		d->mr = mr;
		frpl = ib_alloc_fast_reg_page_list(device, max_page_list_len);
		if (IS_ERR(frpl)) {
			ret = PTR_ERR(frpl);
			goto destroy_pool;
		}
		d->frpl = frpl;
		list_add_tail(&d->entry, &pool->free_list);
	}

out:
	return pool;

destroy_pool:
	srp_destroy_fr_pool(pool);

err:
	pool = ERR_PTR(ret);
	goto out;
}

/**
 * srp_fr_pool_get() - obtain a descriptor suitable for fast registration
 * @pool: Pool to obtain descriptor from.
 */
static struct srp_fr_desc *srp_fr_pool_get(struct srp_fr_pool *pool)
{
	struct srp_fr_desc *d = NULL;
	unsigned long flags;

	spin_lock_irqsave(&pool->lock, flags);
	if (!list_empty(&pool->free_list)) {
		d = list_first_entry(&pool->free_list, typeof(*d), entry);
		list_del(&d->entry);
	}
	spin_unlock_irqrestore(&pool->lock, flags);

	return d;
}

/**
 * srp_fr_pool_put() - put an FR descriptor back in the free list
 * @pool: Pool the descriptor was allocated from.
 * @desc: Pointer to an array of fast registration descriptor pointers.
 * @n:    Number of descriptors to put back.
 *
 * Note: The caller must already have queued an invalidation request for
 * desc->mr->rkey before calling this function.
 */
static void srp_fr_pool_put(struct srp_fr_pool *pool, struct srp_fr_desc **desc,
			    int n)
{
	unsigned long flags;
	int i;

	spin_lock_irqsave(&pool->lock, flags);
	for (i = 0; i < n; i++)
		list_add(&desc[i]->entry, &pool->free_list);
	spin_unlock_irqrestore(&pool->lock, flags);
}

static struct srp_fr_pool *srp_alloc_fr_pool(struct srp_target_port *target)
{
	struct srp_device *dev = target->srp_host->srp_dev;

	return srp_create_fr_pool(dev->dev, dev->pd,
				  target->scsi_host->can_queue,
				  dev->max_pages_per_mr);
}

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static int srp_create_ch_ib(struct srp_rdma_ch *ch)
452
{
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	struct srp_target_port *target = ch->target;
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	struct srp_device *dev = target->srp_host->srp_dev;
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	struct ib_qp_init_attr *init_attr;
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	struct ib_cq *recv_cq, *send_cq;
	struct ib_qp *qp;
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	struct ib_fmr_pool *fmr_pool = NULL;
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	struct srp_fr_pool *fr_pool = NULL;
	const int m = 1 + dev->use_fast_reg;
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	int ret;

	init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
	if (!init_attr)
		return -ENOMEM;

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	recv_cq = ib_create_cq(dev->dev, srp_recv_completion, NULL, ch,
			       target->queue_size, ch->comp_vector);
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	if (IS_ERR(recv_cq)) {
		ret = PTR_ERR(recv_cq);
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		goto err;
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	}

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	send_cq = ib_create_cq(dev->dev, srp_send_completion, NULL, ch,
			       m * target->queue_size, ch->comp_vector);
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	if (IS_ERR(send_cq)) {
		ret = PTR_ERR(send_cq);
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		goto err_recv_cq;
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	}

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	ib_req_notify_cq(recv_cq, IB_CQ_NEXT_COMP);
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	init_attr->event_handler       = srp_qp_event;
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	init_attr->cap.max_send_wr     = m * target->queue_size;
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	init_attr->cap.max_recv_wr     = target->queue_size;
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	init_attr->cap.max_recv_sge    = 1;
	init_attr->cap.max_send_sge    = 1;
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	init_attr->sq_sig_type         = IB_SIGNAL_REQ_WR;
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	init_attr->qp_type             = IB_QPT_RC;
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	init_attr->send_cq             = send_cq;
	init_attr->recv_cq             = recv_cq;
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	qp = ib_create_qp(dev->pd, init_attr);
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	if (IS_ERR(qp)) {
		ret = PTR_ERR(qp);
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		goto err_send_cq;
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	}

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	ret = srp_init_qp(target, qp);
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	if (ret)
		goto err_qp;
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	if (dev->use_fast_reg && dev->has_fr) {
		fr_pool = srp_alloc_fr_pool(target);
		if (IS_ERR(fr_pool)) {
			ret = PTR_ERR(fr_pool);
			shost_printk(KERN_WARNING, target->scsi_host, PFX
				     "FR pool allocation failed (%d)\n", ret);
			goto err_qp;
		}
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		if (ch->fr_pool)
			srp_destroy_fr_pool(ch->fr_pool);
		ch->fr_pool = fr_pool;
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	} else if (!dev->use_fast_reg && dev->has_fmr) {
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		fmr_pool = srp_alloc_fmr_pool(target);
		if (IS_ERR(fmr_pool)) {
			ret = PTR_ERR(fmr_pool);
			shost_printk(KERN_WARNING, target->scsi_host, PFX
				     "FMR pool allocation failed (%d)\n", ret);
			goto err_qp;
		}
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		if (ch->fmr_pool)
			ib_destroy_fmr_pool(ch->fmr_pool);
		ch->fmr_pool = fmr_pool;
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	}

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	if (ch->qp)
		ib_destroy_qp(ch->qp);
	if (ch->recv_cq)
		ib_destroy_cq(ch->recv_cq);
	if (ch->send_cq)
		ib_destroy_cq(ch->send_cq);
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	ch->qp = qp;
	ch->recv_cq = recv_cq;
	ch->send_cq = send_cq;
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	kfree(init_attr);
	return 0;

err_qp:
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	ib_destroy_qp(qp);
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err_send_cq:
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	ib_destroy_cq(send_cq);
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err_recv_cq:
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	ib_destroy_cq(recv_cq);
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err:
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	kfree(init_attr);
	return ret;
}

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/*
 * Note: this function may be called without srp_alloc_iu_bufs() having been
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 * invoked. Hence the ch->[rt]x_ring checks.
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 */
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static void srp_free_ch_ib(struct srp_target_port *target,
			   struct srp_rdma_ch *ch)
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{
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	struct srp_device *dev = target->srp_host->srp_dev;
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	int i;

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	if (ch->cm_id) {
		ib_destroy_cm_id(ch->cm_id);
		ch->cm_id = NULL;
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	}

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	if (dev->use_fast_reg) {
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		if (ch->fr_pool)
			srp_destroy_fr_pool(ch->fr_pool);
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	} else {
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		if (ch->fmr_pool)
			ib_destroy_fmr_pool(ch->fmr_pool);
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	}
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	ib_destroy_qp(ch->qp);
	ib_destroy_cq(ch->send_cq);
	ib_destroy_cq(ch->recv_cq);
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	ch->qp = NULL;
	ch->send_cq = ch->recv_cq = NULL;
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	if (ch->rx_ring) {
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		for (i = 0; i < target->queue_size; ++i)
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			srp_free_iu(target->srp_host, ch->rx_ring[i]);
		kfree(ch->rx_ring);
		ch->rx_ring = NULL;
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	}
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	if (ch->tx_ring) {
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		for (i = 0; i < target->queue_size; ++i)
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			srp_free_iu(target->srp_host, ch->tx_ring[i]);
		kfree(ch->tx_ring);
		ch->tx_ring = NULL;
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	}
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}

static void srp_path_rec_completion(int status,
				    struct ib_sa_path_rec *pathrec,
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				    void *ch_ptr)
601
{
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	struct srp_rdma_ch *ch = ch_ptr;
	struct srp_target_port *target = ch->target;
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	ch->status = status;
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	if (status)
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		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "Got failed path rec status %d\n", status);
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	else
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		ch->path = *pathrec;
	complete(&ch->done);
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}

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static int srp_lookup_path(struct srp_rdma_ch *ch)
615
{
616
	struct srp_target_port *target = ch->target;
617 618
	int ret;

619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639
	ch->path.numb_path = 1;

	init_completion(&ch->done);

	ch->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
					       target->srp_host->srp_dev->dev,
					       target->srp_host->port,
					       &ch->path,
					       IB_SA_PATH_REC_SERVICE_ID |
					       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,
					       ch, &ch->path_query);
	if (ch->path_query_id < 0)
		return ch->path_query_id;

	ret = wait_for_completion_interruptible(&ch->done);
640 641
	if (ret < 0)
		return ret;
642

643
	if (ch->status < 0)
644 645
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Path record query failed\n");
646

647
	return ch->status;
648 649
}

650
static int srp_send_req(struct srp_rdma_ch *ch)
651
{
652
	struct srp_target_port *target = ch->target;
653 654 655 656 657 658 659 660 661 662
	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;

663
	req->param.primary_path		      = &ch->path;
664 665
	req->param.alternate_path 	      = NULL;
	req->param.service_id 		      = target->service_id;
666 667
	req->param.qp_num		      = ch->qp->qp_num;
	req->param.qp_type		      = ch->qp->qp_type;
668 669 670 671 672 673 674 675 676 677 678 679 680 681
	req->param.private_data 	      = &req->priv;
	req->param.private_data_len 	      = sizeof req->priv;
	req->param.flow_control 	      = 1;

	get_random_bytes(&req->param.starting_psn, 4);
	req->param.starting_psn 	     &= 0xffffff;

	/*
	 * Pick some arbitrary defaults here; we could make these
	 * module parameters if anyone cared about setting them.
	 */
	req->param.responder_resources	      = 4;
	req->param.remote_cm_response_timeout = 20;
	req->param.local_cm_response_timeout  = 20;
682
	req->param.retry_count                = target->tl_retry_count;
683 684 685 686 687
	req->param.rnr_retry_count 	      = 7;
	req->param.max_cm_retries 	      = 15;

	req->priv.opcode     	= SRP_LOGIN_REQ;
	req->priv.tag        	= 0;
688
	req->priv.req_it_iu_len = cpu_to_be32(target->max_iu_len);
689 690
	req->priv.req_buf_fmt 	= cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
					      SRP_BUF_FORMAT_INDIRECT);
691
	/*
R
Roland Dreier 已提交
692
	 * In the published SRP specification (draft rev. 16a), the
693 694 695 696 697 698 699 700 701
	 * port identifier format is 8 bytes of ID extension followed
	 * by 8 bytes of GUID.  Older drafts put the two halves in the
	 * opposite order, so that the GUID comes first.
	 *
	 * Targets conforming to these obsolete drafts can be
	 * recognized by the I/O Class they report.
	 */
	if (target->io_class == SRP_REV10_IB_IO_CLASS) {
		memcpy(req->priv.initiator_port_id,
702
		       &target->sgid.global.interface_id, 8);
703
		memcpy(req->priv.initiator_port_id + 8,
704
		       &target->initiator_ext, 8);
705 706 707 708
		memcpy(req->priv.target_port_id,     &target->ioc_guid, 8);
		memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
	} else {
		memcpy(req->priv.initiator_port_id,
709 710
		       &target->initiator_ext, 8);
		memcpy(req->priv.initiator_port_id + 8,
711
		       &target->sgid.global.interface_id, 8);
712 713 714 715
		memcpy(req->priv.target_port_id,     &target->id_ext, 8);
		memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
	}

716 717
	/*
	 * Topspin/Cisco SRP targets will reject our login unless we
718 719
	 * zero out the first 8 bytes of our initiator port ID and set
	 * the second 8 bytes to the local node GUID.
720
	 */
721
	if (srp_target_is_topspin(target)) {
722 723 724 725
		shost_printk(KERN_DEBUG, target->scsi_host,
			     PFX "Topspin/Cisco initiator port ID workaround "
			     "activated for target GUID %016llx\n",
			     (unsigned long long) be64_to_cpu(target->ioc_guid));
726
		memset(req->priv.initiator_port_id, 0, 8);
727
		memcpy(req->priv.initiator_port_id + 8,
728
		       &target->srp_host->srp_dev->dev->node_guid, 8);
729 730
	}

731
	status = ib_send_cm_req(ch->cm_id, &req->param);
732 733 734 735 736 737

	kfree(req);

	return status;
}

738 739 740 741 742 743 744 745 746 747 748 749
static bool srp_queue_remove_work(struct srp_target_port *target)
{
	bool changed = false;

	spin_lock_irq(&target->lock);
	if (target->state != SRP_TARGET_REMOVED) {
		target->state = SRP_TARGET_REMOVED;
		changed = true;
	}
	spin_unlock_irq(&target->lock);

	if (changed)
750
		queue_work(srp_remove_wq, &target->remove_work);
751 752 753 754

	return changed;
}

755 756 757 758 759 760 761 762 763 764 765 766 767 768 769
static bool srp_change_conn_state(struct srp_target_port *target,
				  bool connected)
{
	bool changed = false;

	spin_lock_irq(&target->lock);
	if (target->connected != connected) {
		target->connected = connected;
		changed = true;
	}
	spin_unlock_irq(&target->lock);

	return changed;
}

770 771
static void srp_disconnect_target(struct srp_target_port *target)
{
772 773
	struct srp_rdma_ch *ch = &target->ch;

774 775
	if (srp_change_conn_state(target, false)) {
		/* XXX should send SRP_I_LOGOUT request */
776

777
		if (ib_send_cm_dreq(ch->cm_id, NULL, 0)) {
778 779 780
			shost_printk(KERN_DEBUG, target->scsi_host,
				     PFX "Sending CM DREQ failed\n");
		}
781
	}
782 783
}

784 785
static void srp_free_req_data(struct srp_target_port *target,
			      struct srp_rdma_ch *ch)
786
{
787 788
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
789 790 791
	struct srp_request *req;
	int i;

792
	if (!ch->req_ring)
793 794 795
		return;

	for (i = 0; i < target->req_ring_size; ++i) {
796
		req = &ch->req_ring[i];
797 798 799 800
		if (dev->use_fast_reg)
			kfree(req->fr_list);
		else
			kfree(req->fmr_list);
801
		kfree(req->map_page);
802 803 804 805 806 807
		if (req->indirect_dma_addr) {
			ib_dma_unmap_single(ibdev, req->indirect_dma_addr,
					    target->indirect_size,
					    DMA_TO_DEVICE);
		}
		kfree(req->indirect_desc);
808
	}
809

810 811
	kfree(ch->req_ring);
	ch->req_ring = NULL;
812 813
}

814
static int srp_alloc_req_data(struct srp_rdma_ch *ch)
815
{
816
	struct srp_target_port *target = ch->target;
817 818 819
	struct srp_device *srp_dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = srp_dev->dev;
	struct srp_request *req;
820
	void *mr_list;
821 822 823
	dma_addr_t dma_addr;
	int i, ret = -ENOMEM;

824
	INIT_LIST_HEAD(&ch->free_reqs);
825

826 827 828
	ch->req_ring = kcalloc(target->req_ring_size, sizeof(*ch->req_ring),
			       GFP_KERNEL);
	if (!ch->req_ring)
829 830 831
		goto out;

	for (i = 0; i < target->req_ring_size; ++i) {
832
		req = &ch->req_ring[i];
833 834 835 836 837 838 839 840
		mr_list = kmalloc(target->cmd_sg_cnt * sizeof(void *),
				  GFP_KERNEL);
		if (!mr_list)
			goto out;
		if (srp_dev->use_fast_reg)
			req->fr_list = mr_list;
		else
			req->fmr_list = mr_list;
841
		req->map_page = kmalloc(srp_dev->max_pages_per_mr *
842
					sizeof(void *), GFP_KERNEL);
843 844
		if (!req->map_page)
			goto out;
845
		req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
846
		if (!req->indirect_desc)
847 848 849 850 851 852 853 854 855 856
			goto out;

		dma_addr = ib_dma_map_single(ibdev, req->indirect_desc,
					     target->indirect_size,
					     DMA_TO_DEVICE);
		if (ib_dma_mapping_error(ibdev, dma_addr))
			goto out;

		req->indirect_dma_addr = dma_addr;
		req->index = i;
857
		list_add_tail(&req->list, &ch->free_reqs);
858 859 860 861 862 863 864
	}
	ret = 0;

out:
	return ret;
}

865 866 867 868 869 870 871 872 873 874 875 876 877 878 879
/**
 * srp_del_scsi_host_attr() - Remove attributes defined in the host template.
 * @shost: SCSI host whose attributes to remove from sysfs.
 *
 * Note: Any attributes defined in the host template and that did not exist
 * before invocation of this function will be ignored.
 */
static void srp_del_scsi_host_attr(struct Scsi_Host *shost)
{
	struct device_attribute **attr;

	for (attr = shost->hostt->shost_attrs; attr && *attr; ++attr)
		device_remove_file(&shost->shost_dev, *attr);
}

880 881
static void srp_remove_target(struct srp_target_port *target)
{
882 883
	struct srp_rdma_ch *ch = &target->ch;

884 885
	WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);

886
	srp_del_scsi_host_attr(target->scsi_host);
887
	srp_rport_get(target->rport);
888 889
	srp_remove_host(target->scsi_host);
	scsi_remove_host(target->scsi_host);
890
	srp_stop_rport_timers(target->rport);
891
	srp_disconnect_target(target);
892
	srp_free_ch_ib(target, ch);
893
	cancel_work_sync(&target->tl_err_work);
894
	srp_rport_put(target->rport);
895
	srp_free_req_data(target, ch);
896 897 898 899 900

	spin_lock(&target->srp_host->target_lock);
	list_del(&target->list);
	spin_unlock(&target->srp_host->target_lock);

901 902 903
	scsi_host_put(target->scsi_host);
}

D
David Howells 已提交
904
static void srp_remove_work(struct work_struct *work)
905
{
D
David Howells 已提交
906
	struct srp_target_port *target =
907
		container_of(work, struct srp_target_port, remove_work);
908

909
	WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
910

911
	srp_remove_target(target);
912 913
}

914 915 916 917 918 919 920
static void srp_rport_delete(struct srp_rport *rport)
{
	struct srp_target_port *target = rport->lld_data;

	srp_queue_remove_work(target);
}

921
static int srp_connect_ch(struct srp_rdma_ch *ch)
922
{
923
	struct srp_target_port *target = ch->target;
924 925
	int ret;

926 927
	WARN_ON_ONCE(target->connected);

928 929
	target->qp_in_error = false;

930
	ret = srp_lookup_path(ch);
931 932 933 934
	if (ret)
		return ret;

	while (1) {
935 936
		init_completion(&ch->done);
		ret = srp_send_req(ch);
937 938
		if (ret)
			return ret;
939
		ret = wait_for_completion_interruptible(&ch->done);
940 941
		if (ret < 0)
			return ret;
942 943 944 945 946 947 948

		/*
		 * 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.
		 */
949
		switch (ch->status) {
950
		case 0:
951
			srp_change_conn_state(target, true);
952 953 954
			return 0;

		case SRP_PORT_REDIRECT:
955
			ret = srp_lookup_path(ch);
956 957 958 959 960 961 962
			if (ret)
				return ret;
			break;

		case SRP_DLID_REDIRECT:
			break;

D
David Dillow 已提交
963 964
		case SRP_STALE_CONN:
			shost_printk(KERN_ERR, target->scsi_host, PFX
965
				     "giving up on stale connection\n");
966 967
			ch->status = -ECONNRESET;
			return ch->status;
D
David Dillow 已提交
968

969
		default:
970
			return ch->status;
971 972 973 974
		}
	}
}

975
static int srp_inv_rkey(struct srp_rdma_ch *ch, u32 rkey)
976 977 978 979 980 981 982 983 984 985 986
{
	struct ib_send_wr *bad_wr;
	struct ib_send_wr wr = {
		.opcode		    = IB_WR_LOCAL_INV,
		.wr_id		    = LOCAL_INV_WR_ID_MASK,
		.next		    = NULL,
		.num_sge	    = 0,
		.send_flags	    = 0,
		.ex.invalidate_rkey = rkey,
	};

987
	return ib_post_send(ch->qp, &wr, &bad_wr);
988 989
}

990
static void srp_unmap_data(struct scsi_cmnd *scmnd,
991
			   struct srp_rdma_ch *ch,
992 993
			   struct srp_request *req)
{
994
	struct srp_target_port *target = ch->target;
995 996 997
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
	int i, res;
998

999
	if (!scsi_sglist(scmnd) ||
1000 1001 1002 1003
	    (scmnd->sc_data_direction != DMA_TO_DEVICE &&
	     scmnd->sc_data_direction != DMA_FROM_DEVICE))
		return;

1004 1005 1006 1007
	if (dev->use_fast_reg) {
		struct srp_fr_desc **pfr;

		for (i = req->nmdesc, pfr = req->fr_list; i > 0; i--, pfr++) {
1008
			res = srp_inv_rkey(ch, (*pfr)->mr->rkey);
1009 1010 1011 1012 1013 1014 1015 1016 1017
			if (res < 0) {
				shost_printk(KERN_ERR, target->scsi_host, PFX
				  "Queueing INV WR for rkey %#x failed (%d)\n",
				  (*pfr)->mr->rkey, res);
				queue_work(system_long_wq,
					   &target->tl_err_work);
			}
		}
		if (req->nmdesc)
1018
			srp_fr_pool_put(ch->fr_pool, req->fr_list,
1019 1020 1021 1022 1023 1024 1025
					req->nmdesc);
	} else {
		struct ib_pool_fmr **pfmr;

		for (i = req->nmdesc, pfmr = req->fmr_list; i > 0; i--, pfmr++)
			ib_fmr_pool_unmap(*pfmr);
	}
1026

1027 1028
	ib_dma_unmap_sg(ibdev, scsi_sglist(scmnd), scsi_sg_count(scmnd),
			scmnd->sc_data_direction);
1029 1030
}

B
Bart Van Assche 已提交
1031 1032
/**
 * srp_claim_req - Take ownership of the scmnd associated with a request.
1033
 * @ch: SRP RDMA channel.
B
Bart Van Assche 已提交
1034
 * @req: SRP request.
1035
 * @sdev: If not NULL, only take ownership for this SCSI device.
B
Bart Van Assche 已提交
1036 1037 1038 1039 1040 1041
 * @scmnd: If NULL, take ownership of @req->scmnd. If not NULL, only take
 *         ownership of @req->scmnd if it equals @scmnd.
 *
 * Return value:
 * Either NULL or a pointer to the SCSI command the caller became owner of.
 */
1042
static struct scsi_cmnd *srp_claim_req(struct srp_rdma_ch *ch,
B
Bart Van Assche 已提交
1043
				       struct srp_request *req,
1044
				       struct scsi_device *sdev,
B
Bart Van Assche 已提交
1045 1046 1047 1048
				       struct scsi_cmnd *scmnd)
{
	unsigned long flags;

1049
	spin_lock_irqsave(&ch->lock, flags);
1050 1051 1052
	if (req->scmnd &&
	    (!sdev || req->scmnd->device == sdev) &&
	    (!scmnd || req->scmnd == scmnd)) {
B
Bart Van Assche 已提交
1053 1054 1055 1056 1057
		scmnd = req->scmnd;
		req->scmnd = NULL;
	} else {
		scmnd = NULL;
	}
1058
	spin_unlock_irqrestore(&ch->lock, flags);
B
Bart Van Assche 已提交
1059 1060 1061 1062 1063 1064

	return scmnd;
}

/**
 * srp_free_req() - Unmap data and add request to the free request list.
1065
 * @ch:     SRP RDMA channel.
1066 1067 1068
 * @req:    Request to be freed.
 * @scmnd:  SCSI command associated with @req.
 * @req_lim_delta: Amount to be added to @target->req_lim.
B
Bart Van Assche 已提交
1069
 */
1070 1071
static void srp_free_req(struct srp_rdma_ch *ch, struct srp_request *req,
			 struct scsi_cmnd *scmnd, s32 req_lim_delta)
1072
{
1073 1074
	unsigned long flags;

1075
	srp_unmap_data(scmnd, ch, req);
B
Bart Van Assche 已提交
1076

1077 1078 1079 1080
	spin_lock_irqsave(&ch->lock, flags);
	ch->req_lim += req_lim_delta;
	list_add_tail(&req->list, &ch->free_reqs);
	spin_unlock_irqrestore(&ch->lock, flags);
1081 1082
}

1083 1084
static void srp_finish_req(struct srp_rdma_ch *ch, struct srp_request *req,
			   struct scsi_device *sdev, int result)
1085
{
1086
	struct scsi_cmnd *scmnd = srp_claim_req(ch, req, sdev, NULL);
B
Bart Van Assche 已提交
1087 1088

	if (scmnd) {
1089
		srp_free_req(ch, req, scmnd, 0);
1090
		scmnd->result = result;
B
Bart Van Assche 已提交
1091 1092
		scmnd->scsi_done(scmnd);
	}
1093 1094
}

1095
static void srp_terminate_io(struct srp_rport *rport)
1096
{
1097
	struct srp_target_port *target = rport->lld_data;
1098
	struct srp_rdma_ch *ch = &target->ch;
1099 1100
	struct Scsi_Host *shost = target->scsi_host;
	struct scsi_device *sdev;
1101 1102
	int i;

1103 1104 1105 1106 1107 1108 1109
	/*
	 * Invoking srp_terminate_io() while srp_queuecommand() is running
	 * is not safe. Hence the warning statement below.
	 */
	shost_for_each_device(sdev, shost)
		WARN_ON_ONCE(sdev->request_queue->request_fn_active);

1110
	for (i = 0; i < target->req_ring_size; ++i) {
1111 1112 1113
		struct srp_request *req = &ch->req_ring[i];

		srp_finish_req(ch, req, NULL, DID_TRANSPORT_FAILFAST << 16);
1114 1115
	}
}
1116

1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128
/*
 * It is up to the caller to ensure that srp_rport_reconnect() calls are
 * serialized and that no concurrent srp_queuecommand(), srp_abort(),
 * srp_reset_device() or srp_reset_host() calls will occur while this function
 * is in progress. One way to realize that is not to call this function
 * directly but to call srp_reconnect_rport() instead since that last function
 * serializes calls of this function via rport->mutex and also blocks
 * srp_queuecommand() calls before invoking this function.
 */
static int srp_rport_reconnect(struct srp_rport *rport)
{
	struct srp_target_port *target = rport->lld_data;
1129
	struct srp_rdma_ch *ch = &target->ch;
1130
	int i, ret;
1131

1132
	srp_disconnect_target(target);
1133 1134 1135 1136

	if (target->state == SRP_TARGET_SCANNING)
		return -ENODEV;

1137
	/*
1138 1139 1140
	 * Now get a new local CM ID so that we avoid confusing the target in
	 * case things are really fouled up. Doing so also ensures that all CM
	 * callbacks will have finished before a new QP is allocated.
1141
	 */
1142
	ret = srp_new_cm_id(ch);
1143

1144
	for (i = 0; i < target->req_ring_size; ++i) {
1145 1146 1147
		struct srp_request *req = &ch->req_ring[i];

		srp_finish_req(ch, req, NULL, DID_RESET << 16);
1148
	}
1149

1150 1151 1152 1153 1154
	/*
	 * Whether or not creating a new CM ID succeeded, create a new
	 * QP. This guarantees that all callback functions for the old QP have
	 * finished before any send requests are posted on the new QP.
	 */
1155
	ret += srp_create_ch_ib(ch);
1156

1157
	INIT_LIST_HEAD(&ch->free_tx);
1158
	for (i = 0; i < target->queue_size; ++i)
1159
		list_add(&ch->tx_ring[i]->list, &ch->free_tx);
1160

1161
	if (ret == 0)
1162
		ret = srp_connect_ch(ch);
1163

1164 1165 1166
	if (ret == 0)
		shost_printk(KERN_INFO, target->scsi_host,
			     PFX "reconnect succeeded\n");
1167 1168 1169 1170

	return ret;
}

1171 1172
static void srp_map_desc(struct srp_map_state *state, dma_addr_t dma_addr,
			 unsigned int dma_len, u32 rkey)
1173
{
1174
	struct srp_direct_buf *desc = state->desc;
1175

1176 1177 1178
	desc->va = cpu_to_be64(dma_addr);
	desc->key = cpu_to_be32(rkey);
	desc->len = cpu_to_be32(dma_len);
1179

1180 1181 1182 1183
	state->total_len += dma_len;
	state->desc++;
	state->ndesc++;
}
1184

1185
static int srp_map_finish_fmr(struct srp_map_state *state,
1186
			      struct srp_rdma_ch *ch)
1187 1188 1189
{
	struct ib_pool_fmr *fmr;
	u64 io_addr = 0;
1190

1191
	fmr = ib_fmr_pool_map_phys(ch->fmr_pool, state->pages,
1192 1193 1194
				   state->npages, io_addr);
	if (IS_ERR(fmr))
		return PTR_ERR(fmr);
1195

1196
	*state->next_fmr++ = fmr;
1197
	state->nmdesc++;
1198

1199
	srp_map_desc(state, 0, state->dma_len, fmr->fmr->rkey);
1200

1201 1202 1203
	return 0;
}

1204
static int srp_map_finish_fr(struct srp_map_state *state,
1205
			     struct srp_rdma_ch *ch)
1206
{
1207
	struct srp_target_port *target = ch->target;
1208 1209 1210 1211 1212 1213
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_send_wr *bad_wr;
	struct ib_send_wr wr;
	struct srp_fr_desc *desc;
	u32 rkey;

1214
	desc = srp_fr_pool_get(ch->fr_pool);
1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242
	if (!desc)
		return -ENOMEM;

	rkey = ib_inc_rkey(desc->mr->rkey);
	ib_update_fast_reg_key(desc->mr, rkey);

	memcpy(desc->frpl->page_list, state->pages,
	       sizeof(state->pages[0]) * state->npages);

	memset(&wr, 0, sizeof(wr));
	wr.opcode = IB_WR_FAST_REG_MR;
	wr.wr_id = FAST_REG_WR_ID_MASK;
	wr.wr.fast_reg.iova_start = state->base_dma_addr;
	wr.wr.fast_reg.page_list = desc->frpl;
	wr.wr.fast_reg.page_list_len = state->npages;
	wr.wr.fast_reg.page_shift = ilog2(dev->mr_page_size);
	wr.wr.fast_reg.length = state->dma_len;
	wr.wr.fast_reg.access_flags = (IB_ACCESS_LOCAL_WRITE |
				       IB_ACCESS_REMOTE_READ |
				       IB_ACCESS_REMOTE_WRITE);
	wr.wr.fast_reg.rkey = desc->mr->lkey;

	*state->next_fr++ = desc;
	state->nmdesc++;

	srp_map_desc(state, state->base_dma_addr, state->dma_len,
		     desc->mr->rkey);

1243
	return ib_post_send(ch->qp, &wr, &bad_wr);
1244 1245
}

1246
static int srp_finish_mapping(struct srp_map_state *state,
1247
			      struct srp_rdma_ch *ch)
1248
{
1249
	struct srp_target_port *target = ch->target;
1250 1251 1252 1253 1254
	int ret = 0;

	if (state->npages == 0)
		return 0;

1255
	if (state->npages == 1 && !register_always)
1256
		srp_map_desc(state, state->base_dma_addr, state->dma_len,
1257 1258
			     target->rkey);
	else
1259
		ret = target->srp_host->srp_dev->use_fast_reg ?
1260 1261
			srp_map_finish_fr(state, ch) :
			srp_map_finish_fmr(state, ch);
1262 1263 1264

	if (ret == 0) {
		state->npages = 0;
1265
		state->dma_len = 0;
1266 1267 1268 1269 1270
	}

	return ret;
}

1271 1272 1273 1274 1275 1276 1277 1278
static void srp_map_update_start(struct srp_map_state *state,
				 struct scatterlist *sg, int sg_index,
				 dma_addr_t dma_addr)
{
	state->unmapped_sg = sg;
	state->unmapped_index = sg_index;
	state->unmapped_addr = dma_addr;
}
1279

1280
static int srp_map_sg_entry(struct srp_map_state *state,
1281
			    struct srp_rdma_ch *ch,
1282
			    struct scatterlist *sg, int sg_index,
1283
			    bool use_mr)
1284
{
1285
	struct srp_target_port *target = ch->target;
1286 1287 1288 1289 1290 1291 1292 1293 1294 1295
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
	dma_addr_t dma_addr = ib_sg_dma_address(ibdev, sg);
	unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
	unsigned int len;
	int ret;

	if (!dma_len)
		return 0;

1296 1297 1298 1299
	if (!use_mr) {
		/*
		 * Once we're in direct map mode for a request, we don't
		 * go back to FMR or FR mode, so no need to update anything
1300 1301 1302 1303
		 * other than the descriptor.
		 */
		srp_map_desc(state, dma_addr, dma_len, target->rkey);
		return 0;
1304
	}
1305

1306 1307 1308 1309 1310
	/*
	 * Since not all RDMA HW drivers support non-zero page offsets for
	 * FMR, if we start at an offset into a page, don't merge into the
	 * current FMR mapping. Finish it out, and use the kernel's MR for
	 * this sg entry.
1311
	 */
1312 1313
	if ((!dev->use_fast_reg && dma_addr & ~dev->mr_page_mask) ||
	    dma_len > dev->mr_max_size) {
1314
		ret = srp_finish_mapping(state, ch);
1315 1316 1317 1318 1319 1320
		if (ret)
			return ret;

		srp_map_desc(state, dma_addr, dma_len, target->rkey);
		srp_map_update_start(state, NULL, 0, 0);
		return 0;
1321 1322
	}

1323 1324 1325 1326 1327
	/*
	 * If this is the first sg that will be mapped via FMR or via FR, save
	 * our position. We need to know the first unmapped entry, its index,
	 * and the first unmapped address within that entry to be able to
	 * restart mapping after an error.
1328 1329 1330
	 */
	if (!state->unmapped_sg)
		srp_map_update_start(state, sg, sg_index, dma_addr);
1331

1332
	while (dma_len) {
1333 1334
		unsigned offset = dma_addr & ~dev->mr_page_mask;
		if (state->npages == dev->max_pages_per_mr || offset != 0) {
1335
			ret = srp_finish_mapping(state, ch);
1336 1337
			if (ret)
				return ret;
1338

1339 1340 1341
			srp_map_update_start(state, sg, sg_index, dma_addr);
		}

1342
		len = min_t(unsigned int, dma_len, dev->mr_page_size - offset);
1343

1344 1345
		if (!state->npages)
			state->base_dma_addr = dma_addr;
1346
		state->pages[state->npages++] = dma_addr & dev->mr_page_mask;
1347
		state->dma_len += len;
1348 1349 1350 1351
		dma_addr += len;
		dma_len -= len;
	}

1352 1353
	/*
	 * If the last entry of the MR wasn't a full page, then we need to
1354 1355 1356 1357
	 * close it out and start a new one -- we can only merge at page
	 * boundries.
	 */
	ret = 0;
1358
	if (len != dev->mr_page_size) {
1359
		ret = srp_finish_mapping(state, ch);
1360 1361 1362
		if (!ret)
			srp_map_update_start(state, NULL, 0, 0);
	}
1363 1364 1365
	return ret;
}

1366 1367 1368
static int srp_map_sg(struct srp_map_state *state, struct srp_rdma_ch *ch,
		      struct srp_request *req, struct scatterlist *scat,
		      int count)
1369
{
1370
	struct srp_target_port *target = ch->target;
1371 1372 1373
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
	struct scatterlist *sg;
1374 1375
	int i;
	bool use_mr;
1376 1377 1378

	state->desc	= req->indirect_desc;
	state->pages	= req->map_page;
1379 1380
	if (dev->use_fast_reg) {
		state->next_fr = req->fr_list;
1381
		use_mr = !!ch->fr_pool;
1382 1383
	} else {
		state->next_fmr = req->fmr_list;
1384
		use_mr = !!ch->fmr_pool;
1385
	}
1386 1387

	for_each_sg(scat, sg, count, i) {
1388
		if (srp_map_sg_entry(state, ch, sg, i, use_mr)) {
1389 1390 1391 1392
			/*
			 * Memory registration failed, so backtrack to the
			 * first unmapped entry and continue on without using
			 * memory registration.
1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404
			 */
			dma_addr_t dma_addr;
			unsigned int dma_len;

backtrack:
			sg = state->unmapped_sg;
			i = state->unmapped_index;

			dma_addr = ib_sg_dma_address(ibdev, sg);
			dma_len = ib_sg_dma_len(ibdev, sg);
			dma_len -= (state->unmapped_addr - dma_addr);
			dma_addr = state->unmapped_addr;
1405
			use_mr = false;
1406 1407 1408 1409
			srp_map_desc(state, dma_addr, dma_len, target->rkey);
		}
	}

1410
	if (use_mr && srp_finish_mapping(state, ch))
1411 1412
		goto backtrack;

1413
	req->nmdesc = state->nmdesc;
1414 1415

	return 0;
1416 1417
}

1418
static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_rdma_ch *ch,
1419 1420
			struct srp_request *req)
{
1421
	struct srp_target_port *target = ch->target;
1422
	struct scatterlist *scat;
1423
	struct srp_cmd *cmd = req->cmd->buf;
1424
	int len, nents, count;
1425 1426
	struct srp_device *dev;
	struct ib_device *ibdev;
1427 1428 1429 1430
	struct srp_map_state state;
	struct srp_indirect_buf *indirect_hdr;
	u32 table_len;
	u8 fmt;
1431

1432
	if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
1433 1434 1435 1436
		return sizeof (struct srp_cmd);

	if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
	    scmnd->sc_data_direction != DMA_TO_DEVICE) {
1437 1438 1439
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled data direction %d\n",
			     scmnd->sc_data_direction);
1440 1441 1442
		return -EINVAL;
	}

1443 1444
	nents = scsi_sg_count(scmnd);
	scat  = scsi_sglist(scmnd);
1445

1446
	dev = target->srp_host->srp_dev;
1447 1448 1449
	ibdev = dev->dev;

	count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
1450 1451
	if (unlikely(count == 0))
		return -EIO;
1452 1453 1454

	fmt = SRP_DATA_DESC_DIRECT;
	len = sizeof (struct srp_cmd) +	sizeof (struct srp_direct_buf);
1455

1456
	if (count == 1 && !register_always) {
1457 1458 1459 1460 1461 1462
		/*
		 * The midlayer only generated a single gather/scatter
		 * entry, or DMA mapping coalesced everything to a
		 * single entry.  So a direct descriptor along with
		 * the DMA MR suffices.
		 */
1463
		struct srp_direct_buf *buf = (void *) cmd->add_data;
1464

1465
		buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
1466
		buf->key = cpu_to_be32(target->rkey);
1467
		buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
1468

1469
		req->nmdesc = 0;
1470 1471 1472
		goto map_complete;
	}

1473 1474 1475
	/*
	 * We have more than one scatter/gather entry, so build our indirect
	 * descriptor table, trying to merge as many entries as we can.
1476 1477 1478
	 */
	indirect_hdr = (void *) cmd->add_data;

1479 1480 1481
	ib_dma_sync_single_for_cpu(ibdev, req->indirect_dma_addr,
				   target->indirect_size, DMA_TO_DEVICE);

1482
	memset(&state, 0, sizeof(state));
1483
	srp_map_sg(&state, ch, req, scat, count);
1484

1485 1486 1487 1488 1489
	/* We've mapped the request, now pull as much of the indirect
	 * descriptor table as we can into the command buffer. If this
	 * target is not using an external indirect table, we are
	 * guaranteed to fit into the command, as the SCSI layer won't
	 * give us more S/G entries than we allow.
1490 1491
	 */
	if (state.ndesc == 1) {
1492 1493
		/*
		 * Memory registration collapsed the sg-list into one entry,
1494 1495 1496
		 * so use a direct descriptor.
		 */
		struct srp_direct_buf *buf = (void *) cmd->add_data;
1497

1498
		*buf = req->indirect_desc[0];
1499
		goto map_complete;
1500 1501
	}

1502 1503 1504 1505 1506 1507 1508 1509
	if (unlikely(target->cmd_sg_cnt < state.ndesc &&
						!target->allow_ext_sg)) {
		shost_printk(KERN_ERR, target->scsi_host,
			     "Could not fit S/G list into SRP_CMD\n");
		return -EIO;
	}

	count = min(state.ndesc, target->cmd_sg_cnt);
1510 1511 1512 1513
	table_len = state.ndesc * sizeof (struct srp_direct_buf);

	fmt = SRP_DATA_DESC_INDIRECT;
	len = sizeof(struct srp_cmd) + sizeof (struct srp_indirect_buf);
1514
	len += count * sizeof (struct srp_direct_buf);
1515

1516 1517
	memcpy(indirect_hdr->desc_list, req->indirect_desc,
	       count * sizeof (struct srp_direct_buf));
1518

1519
	indirect_hdr->table_desc.va = cpu_to_be64(req->indirect_dma_addr);
1520 1521 1522 1523 1524
	indirect_hdr->table_desc.key = cpu_to_be32(target->rkey);
	indirect_hdr->table_desc.len = cpu_to_be32(table_len);
	indirect_hdr->len = cpu_to_be32(state.total_len);

	if (scmnd->sc_data_direction == DMA_TO_DEVICE)
1525
		cmd->data_out_desc_cnt = count;
1526
	else
1527 1528 1529 1530
		cmd->data_in_desc_cnt = count;

	ib_dma_sync_single_for_device(ibdev, req->indirect_dma_addr, table_len,
				      DMA_TO_DEVICE);
1531 1532

map_complete:
1533 1534 1535 1536 1537 1538 1539 1540
	if (scmnd->sc_data_direction == DMA_TO_DEVICE)
		cmd->buf_fmt = fmt << 4;
	else
		cmd->buf_fmt = fmt;

	return len;
}

1541 1542 1543
/*
 * Return an IU and possible credit to the free pool
 */
1544
static void srp_put_tx_iu(struct srp_rdma_ch *ch, struct srp_iu *iu,
1545 1546 1547 1548
			  enum srp_iu_type iu_type)
{
	unsigned long flags;

1549 1550
	spin_lock_irqsave(&ch->lock, flags);
	list_add(&iu->list, &ch->free_tx);
1551
	if (iu_type != SRP_IU_RSP)
1552 1553
		++ch->req_lim;
	spin_unlock_irqrestore(&ch->lock, flags);
1554 1555
}

1556
/*
1557
 * Must be called with ch->lock held to protect req_lim and free_tx.
1558
 * If IU is not sent, it must be returned using srp_put_tx_iu().
1559 1560 1561 1562 1563 1564 1565 1566 1567 1568
 *
 * Note:
 * An upper limit for the number of allocated information units for each
 * request type is:
 * - SRP_IU_CMD: SRP_CMD_SQ_SIZE, since the SCSI mid-layer never queues
 *   more than Scsi_Host.can_queue requests.
 * - SRP_IU_TSK_MGMT: SRP_TSK_MGMT_SQ_SIZE.
 * - SRP_IU_RSP: 1, since a conforming SRP target never sends more than
 *   one unanswered SRP request to an initiator.
 */
1569
static struct srp_iu *__srp_get_tx_iu(struct srp_rdma_ch *ch,
1570 1571
				      enum srp_iu_type iu_type)
{
1572
	struct srp_target_port *target = ch->target;
1573 1574 1575
	s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
	struct srp_iu *iu;

1576
	srp_send_completion(ch->send_cq, ch);
1577

1578
	if (list_empty(&ch->free_tx))
1579 1580 1581
		return NULL;

	/* Initiator responses to target requests do not consume credits */
1582
	if (iu_type != SRP_IU_RSP) {
1583
		if (ch->req_lim <= rsv) {
1584 1585 1586 1587
			++target->zero_req_lim;
			return NULL;
		}

1588
		--ch->req_lim;
1589 1590
	}

1591
	iu = list_first_entry(&ch->free_tx, struct srp_iu, list);
1592
	list_del(&iu->list);
1593 1594 1595
	return iu;
}

1596
static int srp_post_send(struct srp_rdma_ch *ch, struct srp_iu *iu, int len)
1597
{
1598
	struct srp_target_port *target = ch->target;
1599 1600 1601 1602 1603
	struct ib_sge list;
	struct ib_send_wr wr, *bad_wr;

	list.addr   = iu->dma;
	list.length = len;
1604
	list.lkey   = target->lkey;
1605 1606

	wr.next       = NULL;
1607
	wr.wr_id      = (uintptr_t) iu;
1608 1609 1610 1611 1612
	wr.sg_list    = &list;
	wr.num_sge    = 1;
	wr.opcode     = IB_WR_SEND;
	wr.send_flags = IB_SEND_SIGNALED;

1613
	return ib_post_send(ch->qp, &wr, &bad_wr);
1614 1615
}

1616
static int srp_post_recv(struct srp_rdma_ch *ch, struct srp_iu *iu)
1617
{
1618
	struct srp_target_port *target = ch->target;
1619
	struct ib_recv_wr wr, *bad_wr;
1620
	struct ib_sge list;
1621 1622 1623

	list.addr   = iu->dma;
	list.length = iu->size;
1624
	list.lkey   = target->lkey;
1625 1626

	wr.next     = NULL;
1627
	wr.wr_id    = (uintptr_t) iu;
1628 1629 1630
	wr.sg_list  = &list;
	wr.num_sge  = 1;

1631
	return ib_post_recv(ch->qp, &wr, &bad_wr);
1632 1633
}

1634
static void srp_process_rsp(struct srp_rdma_ch *ch, struct srp_rsp *rsp)
1635
{
1636
	struct srp_target_port *target = ch->target;
1637 1638 1639 1640 1641
	struct srp_request *req;
	struct scsi_cmnd *scmnd;
	unsigned long flags;

	if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
1642 1643 1644
		spin_lock_irqsave(&ch->lock, flags);
		ch->req_lim += be32_to_cpu(rsp->req_lim_delta);
		spin_unlock_irqrestore(&ch->lock, flags);
1645

1646
		ch->tsk_mgmt_status = -1;
1647
		if (be32_to_cpu(rsp->resp_data_len) >= 4)
1648 1649
			ch->tsk_mgmt_status = rsp->data[3];
		complete(&ch->tsk_mgmt_done);
1650
	} else {
1651 1652
		req = &ch->req_ring[rsp->tag];
		scmnd = srp_claim_req(ch, req, NULL, NULL);
B
Bart Van Assche 已提交
1653
		if (!scmnd) {
1654 1655 1656
			shost_printk(KERN_ERR, target->scsi_host,
				     "Null scmnd for RSP w/tag %016llx\n",
				     (unsigned long long) rsp->tag);
B
Bart Van Assche 已提交
1657

1658 1659 1660
			spin_lock_irqsave(&ch->lock, flags);
			ch->req_lim += be32_to_cpu(rsp->req_lim_delta);
			spin_unlock_irqrestore(&ch->lock, flags);
B
Bart Van Assche 已提交
1661 1662 1663

			return;
		}
1664 1665 1666 1667 1668 1669 1670 1671 1672
		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));
		}

B
Bart Van Assche 已提交
1673
		if (unlikely(rsp->flags & SRP_RSP_FLAG_DIUNDER))
1674
			scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
B
Bart Van Assche 已提交
1675 1676 1677 1678 1679 1680
		else if (unlikely(rsp->flags & SRP_RSP_FLAG_DIOVER))
			scsi_set_resid(scmnd, -be32_to_cpu(rsp->data_in_res_cnt));
		else if (unlikely(rsp->flags & SRP_RSP_FLAG_DOUNDER))
			scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
		else if (unlikely(rsp->flags & SRP_RSP_FLAG_DOOVER))
			scsi_set_resid(scmnd, -be32_to_cpu(rsp->data_out_res_cnt));
1681

1682
		srp_free_req(ch, req, scmnd,
B
Bart Van Assche 已提交
1683 1684
			     be32_to_cpu(rsp->req_lim_delta));

1685 1686
		scmnd->host_scribble = NULL;
		scmnd->scsi_done(scmnd);
1687 1688 1689
	}
}

1690
static int srp_response_common(struct srp_rdma_ch *ch, s32 req_delta,
1691 1692
			       void *rsp, int len)
{
1693
	struct srp_target_port *target = ch->target;
1694
	struct ib_device *dev = target->srp_host->srp_dev->dev;
1695 1696
	unsigned long flags;
	struct srp_iu *iu;
1697
	int err;
1698

1699 1700 1701 1702
	spin_lock_irqsave(&ch->lock, flags);
	ch->req_lim += req_delta;
	iu = __srp_get_tx_iu(ch, SRP_IU_RSP);
	spin_unlock_irqrestore(&ch->lock, flags);
1703

1704 1705 1706
	if (!iu) {
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "no IU available to send response\n");
1707
		return 1;
1708 1709 1710 1711 1712 1713
	}

	ib_dma_sync_single_for_cpu(dev, iu->dma, len, DMA_TO_DEVICE);
	memcpy(iu->buf, rsp, len);
	ib_dma_sync_single_for_device(dev, iu->dma, len, DMA_TO_DEVICE);

1714
	err = srp_post_send(ch, iu, len);
1715
	if (err) {
1716 1717
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "unable to post response: %d\n", err);
1718
		srp_put_tx_iu(ch, iu, SRP_IU_RSP);
1719
	}
1720 1721 1722 1723

	return err;
}

1724
static void srp_process_cred_req(struct srp_rdma_ch *ch,
1725 1726 1727 1728 1729 1730 1731 1732
				 struct srp_cred_req *req)
{
	struct srp_cred_rsp rsp = {
		.opcode = SRP_CRED_RSP,
		.tag = req->tag,
	};
	s32 delta = be32_to_cpu(req->req_lim_delta);

1733 1734
	if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
		shost_printk(KERN_ERR, ch->target->scsi_host, PFX
1735 1736 1737
			     "problems processing SRP_CRED_REQ\n");
}

1738
static void srp_process_aer_req(struct srp_rdma_ch *ch,
1739 1740
				struct srp_aer_req *req)
{
1741
	struct srp_target_port *target = ch->target;
1742 1743 1744 1745 1746 1747 1748 1749 1750
	struct srp_aer_rsp rsp = {
		.opcode = SRP_AER_RSP,
		.tag = req->tag,
	};
	s32 delta = be32_to_cpu(req->req_lim_delta);

	shost_printk(KERN_ERR, target->scsi_host, PFX
		     "ignoring AER for LUN %llu\n", be64_to_cpu(req->lun));

1751
	if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
1752 1753 1754 1755
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "problems processing SRP_AER_REQ\n");
}

1756
static void srp_handle_recv(struct srp_rdma_ch *ch, struct ib_wc *wc)
1757
{
1758
	struct srp_target_port *target = ch->target;
1759
	struct ib_device *dev = target->srp_host->srp_dev->dev;
1760
	struct srp_iu *iu = (struct srp_iu *) (uintptr_t) wc->wr_id;
1761
	int res;
1762 1763
	u8 opcode;

1764
	ib_dma_sync_single_for_cpu(dev, iu->dma, ch->max_ti_iu_len,
1765
				   DMA_FROM_DEVICE);
1766 1767 1768 1769

	opcode = *(u8 *) iu->buf;

	if (0) {
1770 1771
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "recv completion, opcode 0x%02x\n", opcode);
B
Bart Van Assche 已提交
1772 1773
		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
			       iu->buf, wc->byte_len, true);
1774 1775 1776 1777
	}

	switch (opcode) {
	case SRP_RSP:
1778
		srp_process_rsp(ch, iu->buf);
1779 1780
		break;

1781
	case SRP_CRED_REQ:
1782
		srp_process_cred_req(ch, iu->buf);
1783 1784 1785
		break;

	case SRP_AER_REQ:
1786
		srp_process_aer_req(ch, iu->buf);
1787 1788
		break;

1789 1790
	case SRP_T_LOGOUT:
		/* XXX Handle target logout */
1791 1792
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Got target logout request\n");
1793 1794 1795
		break;

	default:
1796 1797
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled SRP opcode 0x%02x\n", opcode);
1798 1799 1800
		break;
	}

1801
	ib_dma_sync_single_for_device(dev, iu->dma, ch->max_ti_iu_len,
1802
				      DMA_FROM_DEVICE);
1803

1804
	res = srp_post_recv(ch, iu);
1805 1806 1807
	if (res != 0)
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "Recv failed with error code %d\n", res);
1808 1809
}

1810 1811
/**
 * srp_tl_err_work() - handle a transport layer error
1812
 * @work: Work structure embedded in an SRP target port.
1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825
 *
 * Note: This function may get invoked before the rport has been created,
 * hence the target->rport test.
 */
static void srp_tl_err_work(struct work_struct *work)
{
	struct srp_target_port *target;

	target = container_of(work, struct srp_target_port, tl_err_work);
	if (target->rport)
		srp_start_tl_fail_timers(target->rport);
}

1826 1827
static void srp_handle_qp_err(u64 wr_id, enum ib_wc_status wc_status,
			      bool send_err, struct srp_target_port *target)
1828
{
1829
	if (target->connected && !target->qp_in_error) {
1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843
		if (wr_id & LOCAL_INV_WR_ID_MASK) {
			shost_printk(KERN_ERR, target->scsi_host, PFX
				     "LOCAL_INV failed with status %d\n",
				     wc_status);
		} else if (wr_id & FAST_REG_WR_ID_MASK) {
			shost_printk(KERN_ERR, target->scsi_host, PFX
				     "FAST_REG_MR failed status %d\n",
				     wc_status);
		} else {
			shost_printk(KERN_ERR, target->scsi_host,
				     PFX "failed %s status %d for iu %p\n",
				     send_err ? "send" : "receive",
				     wc_status, (void *)(uintptr_t)wr_id);
		}
1844
		queue_work(system_long_wq, &target->tl_err_work);
1845
	}
1846 1847 1848
	target->qp_in_error = true;
}

1849
static void srp_recv_completion(struct ib_cq *cq, void *ch_ptr)
1850
{
1851
	struct srp_rdma_ch *ch = ch_ptr;
1852 1853 1854 1855
	struct ib_wc wc;

	ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
	while (ib_poll_cq(cq, 1, &wc) > 0) {
1856
		if (likely(wc.status == IB_WC_SUCCESS)) {
1857
			srp_handle_recv(ch, &wc);
1858
		} else {
1859 1860
			srp_handle_qp_err(wc.wr_id, wc.status, false,
					  ch->target);
1861
		}
1862 1863 1864
	}
}

1865
static void srp_send_completion(struct ib_cq *cq, void *ch_ptr)
1866
{
1867
	struct srp_rdma_ch *ch = ch_ptr;
1868
	struct ib_wc wc;
1869
	struct srp_iu *iu;
1870 1871

	while (ib_poll_cq(cq, 1, &wc) > 0) {
1872 1873
		if (likely(wc.status == IB_WC_SUCCESS)) {
			iu = (struct srp_iu *) (uintptr_t) wc.wr_id;
1874
			list_add(&iu->list, &ch->free_tx);
1875
		} else {
1876 1877
			srp_handle_qp_err(wc.wr_id, wc.status, true,
					  ch->target);
1878
		}
1879 1880 1881
	}
}

1882
static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
1883
{
1884
	struct srp_target_port *target = host_to_target(shost);
1885
	struct srp_rport *rport = target->rport;
1886
	struct srp_rdma_ch *ch;
1887 1888 1889
	struct srp_request *req;
	struct srp_iu *iu;
	struct srp_cmd *cmd;
1890
	struct ib_device *dev;
1891
	unsigned long flags;
1892
	int len, ret;
1893 1894 1895 1896 1897 1898 1899 1900 1901 1902
	const bool in_scsi_eh = !in_interrupt() && current == shost->ehandler;

	/*
	 * The SCSI EH thread is the only context from which srp_queuecommand()
	 * can get invoked for blocked devices (SDEV_BLOCK /
	 * SDEV_CREATED_BLOCK). Avoid racing with srp_reconnect_rport() by
	 * locking the rport mutex if invoked from inside the SCSI EH.
	 */
	if (in_scsi_eh)
		mutex_lock(&rport->mutex);
1903

1904 1905 1906
	scmnd->result = srp_chkready(target->rport);
	if (unlikely(scmnd->result))
		goto err;
1907

1908 1909 1910 1911
	ch = &target->ch;

	spin_lock_irqsave(&ch->lock, flags);
	iu = __srp_get_tx_iu(ch, SRP_IU_CMD);
1912
	if (!iu)
1913 1914
		goto err_unlock;

1915
	req = list_first_entry(&ch->free_reqs, struct srp_request, list);
1916
	list_del(&req->list);
1917
	spin_unlock_irqrestore(&ch->lock, flags);
1918

1919
	dev = target->srp_host->srp_dev->dev;
1920
	ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len,
1921
				   DMA_TO_DEVICE);
1922

1923
	scmnd->host_scribble = (void *) req;
1924 1925 1926 1927 1928 1929

	cmd = iu->buf;
	memset(cmd, 0, sizeof *cmd);

	cmd->opcode = SRP_CMD;
	cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
1930
	cmd->tag    = req->index;
1931 1932 1933 1934 1935
	memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);

	req->scmnd    = scmnd;
	req->cmd      = iu;

1936
	len = srp_map_data(scmnd, ch, req);
1937
	if (len < 0) {
1938
		shost_printk(KERN_ERR, target->scsi_host,
1939 1940 1941 1942
			     PFX "Failed to map data (%d)\n", len);
		/*
		 * If we ran out of memory descriptors (-ENOMEM) because an
		 * application is queuing many requests with more than
1943
		 * max_pages_per_mr sg-list elements, tell the SCSI mid-layer
1944 1945 1946 1947
		 * to reduce queue depth temporarily.
		 */
		scmnd->result = len == -ENOMEM ?
			DID_OK << 16 | QUEUE_FULL << 1 : DID_ERROR << 16;
1948
		goto err_iu;
1949 1950
	}

1951
	ib_dma_sync_single_for_device(dev, iu->dma, target->max_iu_len,
1952
				      DMA_TO_DEVICE);
1953

1954
	if (srp_post_send(ch, iu, len)) {
1955
		shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
1956 1957 1958
		goto err_unmap;
	}

1959 1960
	ret = 0;

1961 1962 1963 1964
unlock_rport:
	if (in_scsi_eh)
		mutex_unlock(&rport->mutex);

1965
	return ret;
1966 1967

err_unmap:
1968
	srp_unmap_data(scmnd, ch, req);
1969

1970
err_iu:
1971
	srp_put_tx_iu(ch, iu, SRP_IU_CMD);
1972

1973 1974 1975 1976 1977 1978
	/*
	 * Avoid that the loops that iterate over the request ring can
	 * encounter a dangling SCSI command pointer.
	 */
	req->scmnd = NULL;

1979 1980
	spin_lock_irqsave(&ch->lock, flags);
	list_add(&req->list, &ch->free_reqs);
1981 1982

err_unlock:
1983
	spin_unlock_irqrestore(&ch->lock, flags);
1984

1985 1986 1987 1988 1989 1990 1991
err:
	if (scmnd->result) {
		scmnd->scsi_done(scmnd);
		ret = 0;
	} else {
		ret = SCSI_MLQUEUE_HOST_BUSY;
	}
1992

1993
	goto unlock_rport;
1994 1995
}

1996 1997
/*
 * Note: the resources allocated in this function are freed in
1998
 * srp_free_ch_ib().
1999
 */
2000
static int srp_alloc_iu_bufs(struct srp_rdma_ch *ch)
2001
{
2002
	struct srp_target_port *target = ch->target;
2003 2004
	int i;

2005 2006 2007
	ch->rx_ring = kcalloc(target->queue_size, sizeof(*ch->rx_ring),
			      GFP_KERNEL);
	if (!ch->rx_ring)
2008
		goto err_no_ring;
2009 2010 2011
	ch->tx_ring = kcalloc(target->queue_size, sizeof(*ch->tx_ring),
			      GFP_KERNEL);
	if (!ch->tx_ring)
2012 2013 2014
		goto err_no_ring;

	for (i = 0; i < target->queue_size; ++i) {
2015 2016 2017 2018
		ch->rx_ring[i] = srp_alloc_iu(target->srp_host,
					      ch->max_ti_iu_len,
					      GFP_KERNEL, DMA_FROM_DEVICE);
		if (!ch->rx_ring[i])
2019 2020 2021
			goto err;
	}

2022
	for (i = 0; i < target->queue_size; ++i) {
2023 2024 2025 2026
		ch->tx_ring[i] = srp_alloc_iu(target->srp_host,
					      target->max_iu_len,
					      GFP_KERNEL, DMA_TO_DEVICE);
		if (!ch->tx_ring[i])
2027
			goto err;
2028

2029
		list_add(&ch->tx_ring[i]->list, &ch->free_tx);
2030 2031 2032 2033 2034
	}

	return 0;

err:
2035
	for (i = 0; i < target->queue_size; ++i) {
2036 2037
		srp_free_iu(target->srp_host, ch->rx_ring[i]);
		srp_free_iu(target->srp_host, ch->tx_ring[i]);
2038 2039
	}

2040 2041

err_no_ring:
2042 2043 2044 2045
	kfree(ch->tx_ring);
	ch->tx_ring = NULL;
	kfree(ch->rx_ring);
	ch->rx_ring = NULL;
2046

2047 2048 2049
	return -ENOMEM;
}

2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076
static uint32_t srp_compute_rq_tmo(struct ib_qp_attr *qp_attr, int attr_mask)
{
	uint64_t T_tr_ns, max_compl_time_ms;
	uint32_t rq_tmo_jiffies;

	/*
	 * According to section 11.2.4.2 in the IBTA spec (Modify Queue Pair,
	 * table 91), both the QP timeout and the retry count have to be set
	 * for RC QP's during the RTR to RTS transition.
	 */
	WARN_ON_ONCE((attr_mask & (IB_QP_TIMEOUT | IB_QP_RETRY_CNT)) !=
		     (IB_QP_TIMEOUT | IB_QP_RETRY_CNT));

	/*
	 * Set target->rq_tmo_jiffies to one second more than the largest time
	 * it can take before an error completion is generated. See also
	 * C9-140..142 in the IBTA spec for more information about how to
	 * convert the QP Local ACK Timeout value to nanoseconds.
	 */
	T_tr_ns = 4096 * (1ULL << qp_attr->timeout);
	max_compl_time_ms = qp_attr->retry_cnt * 4 * T_tr_ns;
	do_div(max_compl_time_ms, NSEC_PER_MSEC);
	rq_tmo_jiffies = msecs_to_jiffies(max_compl_time_ms + 1000);

	return rq_tmo_jiffies;
}

2077 2078
static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
			       struct srp_login_rsp *lrsp,
2079
			       struct srp_rdma_ch *ch)
2080
{
2081
	struct srp_target_port *target = ch->target;
2082 2083 2084 2085 2086 2087
	struct ib_qp_attr *qp_attr = NULL;
	int attr_mask = 0;
	int ret;
	int i;

	if (lrsp->opcode == SRP_LOGIN_RSP) {
2088 2089
		ch->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len);
		ch->req_lim       = be32_to_cpu(lrsp->req_lim_delta);
2090 2091 2092 2093 2094 2095

		/*
		 * Reserve credits for task management so we don't
		 * bounce requests back to the SCSI mid-layer.
		 */
		target->scsi_host->can_queue
2096
			= min(ch->req_lim - SRP_TSK_MGMT_SQ_SIZE,
2097
			      target->scsi_host->can_queue);
2098 2099 2100
		target->scsi_host->cmd_per_lun
			= min_t(int, target->scsi_host->can_queue,
				target->scsi_host->cmd_per_lun);
2101 2102 2103 2104 2105 2106 2107
	} else {
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);
		ret = -ECONNRESET;
		goto error;
	}

2108 2109
	if (!ch->rx_ring) {
		ret = srp_alloc_iu_bufs(ch);
2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123
		if (ret)
			goto error;
	}

	ret = -ENOMEM;
	qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
	if (!qp_attr)
		goto error;

	qp_attr->qp_state = IB_QPS_RTR;
	ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
	if (ret)
		goto error_free;

2124
	ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2125 2126 2127
	if (ret)
		goto error_free;

2128
	for (i = 0; i < target->queue_size; i++) {
2129 2130 2131
		struct srp_iu *iu = ch->rx_ring[i];

		ret = srp_post_recv(ch, iu);
2132 2133 2134 2135 2136 2137 2138 2139 2140
		if (ret)
			goto error_free;
	}

	qp_attr->qp_state = IB_QPS_RTS;
	ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
	if (ret)
		goto error_free;

2141 2142
	target->rq_tmo_jiffies = srp_compute_rq_tmo(qp_attr, attr_mask);

2143
	ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2144 2145 2146 2147 2148 2149 2150 2151 2152
	if (ret)
		goto error_free;

	ret = ib_send_cm_rtu(cm_id, NULL, 0);

error_free:
	kfree(qp_attr);

error:
2153
	ch->status = ret;
2154 2155
}

2156 2157
static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
			       struct ib_cm_event *event,
2158
			       struct srp_rdma_ch *ch)
2159
{
2160
	struct srp_target_port *target = ch->target;
2161
	struct Scsi_Host *shost = target->scsi_host;
2162 2163 2164 2165 2166 2167
	struct ib_class_port_info *cpi;
	int opcode;

	switch (event->param.rej_rcvd.reason) {
	case IB_CM_REJ_PORT_CM_REDIRECT:
		cpi = event->param.rej_rcvd.ari;
2168 2169
		ch->path.dlid = cpi->redirect_lid;
		ch->path.pkey = cpi->redirect_pkey;
2170
		cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
2171
		memcpy(ch->path.dgid.raw, cpi->redirect_gid, 16);
2172

2173
		ch->status = ch->path.dlid ?
2174 2175 2176 2177
			SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
		break;

	case IB_CM_REJ_PORT_REDIRECT:
2178
		if (srp_target_is_topspin(target)) {
2179 2180 2181 2182 2183
			/*
			 * Topspin/Cisco SRP gateways incorrectly send
			 * reject reason code 25 when they mean 24
			 * (port redirect).
			 */
2184
			memcpy(ch->path.dgid.raw,
2185 2186
			       event->param.rej_rcvd.ari, 16);

2187 2188
			shost_printk(KERN_DEBUG, shost,
				     PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
2189 2190
				     be64_to_cpu(ch->path.dgid.global.subnet_prefix),
				     be64_to_cpu(ch->path.dgid.global.interface_id));
2191

2192
			ch->status = SRP_PORT_REDIRECT;
2193
		} else {
2194 2195
			shost_printk(KERN_WARNING, shost,
				     "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
2196
			ch->status = -ECONNRESET;
2197 2198 2199 2200
		}
		break;

	case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
2201 2202
		shost_printk(KERN_WARNING, shost,
			    "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
2203
		ch->status = -ECONNRESET;
2204 2205 2206 2207 2208 2209 2210 2211 2212
		break;

	case IB_CM_REJ_CONSUMER_DEFINED:
		opcode = *(u8 *) event->private_data;
		if (opcode == SRP_LOGIN_REJ) {
			struct srp_login_rej *rej = event->private_data;
			u32 reason = be32_to_cpu(rej->reason);

			if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
2213 2214
				shost_printk(KERN_WARNING, shost,
					     PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
2215
			else
B
Bart Van Assche 已提交
2216 2217
				shost_printk(KERN_WARNING, shost, PFX
					     "SRP LOGIN from %pI6 to %pI6 REJECTED, reason 0x%08x\n",
2218 2219
					     target->sgid.raw,
					     target->orig_dgid.raw, reason);
2220
		} else
2221 2222 2223
			shost_printk(KERN_WARNING, shost,
				     "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
				     " opcode 0x%02x\n", opcode);
2224
		ch->status = -ECONNRESET;
2225 2226
		break;

D
David Dillow 已提交
2227 2228
	case IB_CM_REJ_STALE_CONN:
		shost_printk(KERN_WARNING, shost, "  REJ reason: stale connection\n");
2229
		ch->status = SRP_STALE_CONN;
D
David Dillow 已提交
2230 2231
		break;

2232
	default:
2233 2234
		shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
			     event->param.rej_rcvd.reason);
2235
		ch->status = -ECONNRESET;
2236 2237 2238 2239 2240
	}
}

static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
{
2241 2242
	struct srp_rdma_ch *ch = cm_id->context;
	struct srp_target_port *target = ch->target;
2243 2244 2245 2246
	int comp = 0;

	switch (event->event) {
	case IB_CM_REQ_ERROR:
2247 2248
		shost_printk(KERN_DEBUG, target->scsi_host,
			     PFX "Sending CM REQ failed\n");
2249
		comp = 1;
2250
		ch->status = -ECONNRESET;
2251 2252 2253 2254
		break;

	case IB_CM_REP_RECEIVED:
		comp = 1;
2255
		srp_cm_rep_handler(cm_id, event->private_data, ch);
2256 2257 2258
		break;

	case IB_CM_REJ_RECEIVED:
2259
		shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
2260 2261
		comp = 1;

2262
		srp_cm_rej_handler(cm_id, event, ch);
2263 2264
		break;

2265
	case IB_CM_DREQ_RECEIVED:
2266 2267
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "DREQ received - connection closed\n");
2268
		srp_change_conn_state(target, false);
2269
		if (ib_send_cm_drep(cm_id, NULL, 0))
2270 2271
			shost_printk(KERN_ERR, target->scsi_host,
				     PFX "Sending CM DREP failed\n");
2272
		queue_work(system_long_wq, &target->tl_err_work);
2273 2274 2275
		break;

	case IB_CM_TIMEWAIT_EXIT:
2276 2277
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "connection closed\n");
2278
		comp = 1;
2279

2280
		ch->status = 0;
2281 2282
		break;

2283 2284 2285 2286 2287
	case IB_CM_MRA_RECEIVED:
	case IB_CM_DREQ_ERROR:
	case IB_CM_DREP_RECEIVED:
		break;

2288
	default:
2289 2290
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled CM event %d\n", event->event);
2291 2292 2293 2294
		break;
	}

	if (comp)
2295
		complete(&ch->done);
2296 2297 2298 2299

	return 0;
}

2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319
/**
 * srp_change_queue_depth - setting device queue depth
 * @sdev: scsi device struct
 * @qdepth: requested queue depth
 * @reason: SCSI_QDEPTH_DEFAULT/SCSI_QDEPTH_QFULL/SCSI_QDEPTH_RAMP_UP
 * (see include/scsi/scsi_host.h for definition)
 *
 * Returns queue depth.
 */
static int
srp_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
{
	struct Scsi_Host *shost = sdev->host;
	int max_depth;
	if (reason == SCSI_QDEPTH_DEFAULT || reason == SCSI_QDEPTH_RAMP_UP) {
		max_depth = shost->can_queue;
		if (!sdev->tagged_supported)
			max_depth = 1;
		if (qdepth > max_depth)
			qdepth = max_depth;
2320
		scsi_adjust_queue_depth(sdev, qdepth);
2321 2322 2323 2324 2325 2326 2327 2328
	} else if (reason == SCSI_QDEPTH_QFULL)
		scsi_track_queue_full(sdev, qdepth);
	else
		return -EOPNOTSUPP;

	return sdev->queue_depth;
}

2329 2330
static int srp_send_tsk_mgmt(struct srp_rdma_ch *ch, u64 req_tag,
			     unsigned int lun, u8 func)
2331
{
2332
	struct srp_target_port *target = ch->target;
2333
	struct srp_rport *rport = target->rport;
2334
	struct ib_device *dev = target->srp_host->srp_dev->dev;
2335 2336 2337
	struct srp_iu *iu;
	struct srp_tsk_mgmt *tsk_mgmt;

2338 2339 2340
	if (!target->connected || target->qp_in_error)
		return -1;

2341
	init_completion(&ch->tsk_mgmt_done);
2342

2343
	/*
2344
	 * Lock the rport mutex to avoid that srp_create_ch_ib() is
2345 2346 2347
	 * invoked while a task management function is being sent.
	 */
	mutex_lock(&rport->mutex);
2348 2349 2350
	spin_lock_irq(&ch->lock);
	iu = __srp_get_tx_iu(ch, SRP_IU_TSK_MGMT);
	spin_unlock_irq(&ch->lock);
2351

2352 2353 2354
	if (!iu) {
		mutex_unlock(&rport->mutex);

2355
		return -1;
2356
	}
2357

2358 2359
	ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
				   DMA_TO_DEVICE);
2360 2361 2362 2363
	tsk_mgmt = iu->buf;
	memset(tsk_mgmt, 0, sizeof *tsk_mgmt);

	tsk_mgmt->opcode 	= SRP_TSK_MGMT;
2364 2365
	tsk_mgmt->lun		= cpu_to_be64((u64) lun << 48);
	tsk_mgmt->tag		= req_tag | SRP_TAG_TSK_MGMT;
2366
	tsk_mgmt->tsk_mgmt_func = func;
2367
	tsk_mgmt->task_tag	= req_tag;
2368

2369 2370
	ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
				      DMA_TO_DEVICE);
2371 2372
	if (srp_post_send(ch, iu, sizeof(*tsk_mgmt))) {
		srp_put_tx_iu(ch, iu, SRP_IU_TSK_MGMT);
2373 2374
		mutex_unlock(&rport->mutex);

2375 2376
		return -1;
	}
2377
	mutex_unlock(&rport->mutex);
2378

2379
	if (!wait_for_completion_timeout(&ch->tsk_mgmt_done,
2380
					 msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
2381
		return -1;
2382

2383 2384 2385
	return 0;
}

2386 2387
static int srp_abort(struct scsi_cmnd *scmnd)
{
2388
	struct srp_target_port *target = host_to_target(scmnd->device->host);
2389
	struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
2390
	struct srp_rdma_ch *ch;
2391
	int ret;
2392

2393
	shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
2394

2395 2396
	ch = &target->ch;
	if (!req || !srp_claim_req(ch, req, NULL, scmnd))
2397
		return SUCCESS;
2398
	if (srp_send_tsk_mgmt(ch, req->index, scmnd->device->lun,
2399
			      SRP_TSK_ABORT_TASK) == 0)
2400
		ret = SUCCESS;
2401
	else if (target->rport->state == SRP_RPORT_LOST)
2402
		ret = FAST_IO_FAIL;
2403 2404
	else
		ret = FAILED;
2405
	srp_free_req(ch, req, scmnd, 0);
B
Bart Van Assche 已提交
2406
	scmnd->result = DID_ABORT << 16;
2407
	scmnd->scsi_done(scmnd);
2408

2409
	return ret;
2410 2411 2412 2413
}

static int srp_reset_device(struct scsi_cmnd *scmnd)
{
2414
	struct srp_target_port *target = host_to_target(scmnd->device->host);
2415
	struct srp_rdma_ch *ch = &target->ch;
2416
	int i;
2417

2418
	shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
2419

2420
	if (srp_send_tsk_mgmt(ch, SRP_TAG_NO_REQ, scmnd->device->lun,
2421
			      SRP_TSK_LUN_RESET))
2422
		return FAILED;
2423
	if (ch->tsk_mgmt_status)
2424 2425
		return FAILED;

2426
	for (i = 0; i < target->req_ring_size; ++i) {
2427 2428 2429
		struct srp_request *req = &ch->req_ring[i];

		srp_finish_req(ch, req, scmnd->device, DID_RESET << 16);
2430
	}
2431 2432

	return SUCCESS;
2433 2434 2435 2436 2437 2438
}

static int srp_reset_host(struct scsi_cmnd *scmnd)
{
	struct srp_target_port *target = host_to_target(scmnd->device->host);

2439
	shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
2440

2441
	return srp_reconnect_rport(target->rport) == 0 ? SUCCESS : FAILED;
2442 2443
}

2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458
static int srp_slave_configure(struct scsi_device *sdev)
{
	struct Scsi_Host *shost = sdev->host;
	struct srp_target_port *target = host_to_target(shost);
	struct request_queue *q = sdev->request_queue;
	unsigned long timeout;

	if (sdev->type == TYPE_DISK) {
		timeout = max_t(unsigned, 30 * HZ, target->rq_tmo_jiffies);
		blk_queue_rq_timeout(q, timeout);
	}

	return 0;
}

2459 2460
static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
			   char *buf)
2461
{
2462
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2463 2464 2465 2466 2467

	return sprintf(buf, "0x%016llx\n",
		       (unsigned long long) be64_to_cpu(target->id_ext));
}

2468 2469
static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
			     char *buf)
2470
{
2471
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2472 2473 2474 2475 2476

	return sprintf(buf, "0x%016llx\n",
		       (unsigned long long) be64_to_cpu(target->ioc_guid));
}

2477 2478
static ssize_t show_service_id(struct device *dev,
			       struct device_attribute *attr, char *buf)
2479
{
2480
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2481 2482 2483 2484 2485

	return sprintf(buf, "0x%016llx\n",
		       (unsigned long long) be64_to_cpu(target->service_id));
}

2486 2487
static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
			 char *buf)
2488
{
2489
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2490

2491
	return sprintf(buf, "0x%04x\n", be16_to_cpu(target->pkey));
2492 2493
}

B
Bart Van Assche 已提交
2494 2495 2496 2497 2498
static ssize_t show_sgid(struct device *dev, struct device_attribute *attr,
			 char *buf)
{
	struct srp_target_port *target = host_to_target(class_to_shost(dev));

2499
	return sprintf(buf, "%pI6\n", target->sgid.raw);
B
Bart Van Assche 已提交
2500 2501
}

2502 2503
static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
			 char *buf)
2504
{
2505
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2506
	struct srp_rdma_ch *ch = &target->ch;
2507

2508
	return sprintf(buf, "%pI6\n", ch->path.dgid.raw);
2509 2510
}

2511 2512
static ssize_t show_orig_dgid(struct device *dev,
			      struct device_attribute *attr, char *buf)
2513
{
2514
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2515

2516
	return sprintf(buf, "%pI6\n", target->orig_dgid.raw);
2517 2518
}

2519 2520 2521 2522 2523
static ssize_t show_req_lim(struct device *dev,
			    struct device_attribute *attr, char *buf)
{
	struct srp_target_port *target = host_to_target(class_to_shost(dev));

2524
	return sprintf(buf, "%d\n", target->ch.req_lim);
2525 2526
}

2527 2528
static ssize_t show_zero_req_lim(struct device *dev,
				 struct device_attribute *attr, char *buf)
2529
{
2530
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2531 2532 2533 2534

	return sprintf(buf, "%d\n", target->zero_req_lim);
}

2535 2536
static ssize_t show_local_ib_port(struct device *dev,
				  struct device_attribute *attr, char *buf)
2537
{
2538
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2539 2540 2541 2542

	return sprintf(buf, "%d\n", target->srp_host->port);
}

2543 2544
static ssize_t show_local_ib_device(struct device *dev,
				    struct device_attribute *attr, char *buf)
2545
{
2546
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2547

2548
	return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
2549 2550
}

2551 2552 2553 2554 2555 2556 2557 2558
static ssize_t show_comp_vector(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct srp_target_port *target = host_to_target(class_to_shost(dev));

	return sprintf(buf, "%d\n", target->comp_vector);
}

2559 2560 2561 2562 2563 2564 2565 2566
static ssize_t show_tl_retry_count(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	struct srp_target_port *target = host_to_target(class_to_shost(dev));

	return sprintf(buf, "%d\n", target->tl_retry_count);
}

2567 2568 2569 2570 2571 2572 2573 2574
static ssize_t show_cmd_sg_entries(struct device *dev,
				   struct device_attribute *attr, char *buf)
{
	struct srp_target_port *target = host_to_target(class_to_shost(dev));

	return sprintf(buf, "%u\n", target->cmd_sg_cnt);
}

2575 2576 2577 2578 2579 2580 2581 2582
static ssize_t show_allow_ext_sg(struct device *dev,
				 struct device_attribute *attr, char *buf)
{
	struct srp_target_port *target = host_to_target(class_to_shost(dev));

	return sprintf(buf, "%s\n", target->allow_ext_sg ? "true" : "false");
}

2583 2584 2585 2586
static DEVICE_ATTR(id_ext,	    S_IRUGO, show_id_ext,	   NULL);
static DEVICE_ATTR(ioc_guid,	    S_IRUGO, show_ioc_guid,	   NULL);
static DEVICE_ATTR(service_id,	    S_IRUGO, show_service_id,	   NULL);
static DEVICE_ATTR(pkey,	    S_IRUGO, show_pkey,		   NULL);
B
Bart Van Assche 已提交
2587
static DEVICE_ATTR(sgid,	    S_IRUGO, show_sgid,		   NULL);
2588 2589
static DEVICE_ATTR(dgid,	    S_IRUGO, show_dgid,		   NULL);
static DEVICE_ATTR(orig_dgid,	    S_IRUGO, show_orig_dgid,	   NULL);
2590
static DEVICE_ATTR(req_lim,         S_IRUGO, show_req_lim,         NULL);
2591 2592 2593
static DEVICE_ATTR(zero_req_lim,    S_IRUGO, show_zero_req_lim,	   NULL);
static DEVICE_ATTR(local_ib_port,   S_IRUGO, show_local_ib_port,   NULL);
static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
2594
static DEVICE_ATTR(comp_vector,     S_IRUGO, show_comp_vector,     NULL);
2595
static DEVICE_ATTR(tl_retry_count,  S_IRUGO, show_tl_retry_count,  NULL);
2596
static DEVICE_ATTR(cmd_sg_entries,  S_IRUGO, show_cmd_sg_entries,  NULL);
2597
static DEVICE_ATTR(allow_ext_sg,    S_IRUGO, show_allow_ext_sg,    NULL);
2598 2599 2600 2601 2602 2603

static struct device_attribute *srp_host_attrs[] = {
	&dev_attr_id_ext,
	&dev_attr_ioc_guid,
	&dev_attr_service_id,
	&dev_attr_pkey,
B
Bart Van Assche 已提交
2604
	&dev_attr_sgid,
2605 2606
	&dev_attr_dgid,
	&dev_attr_orig_dgid,
2607
	&dev_attr_req_lim,
2608 2609 2610
	&dev_attr_zero_req_lim,
	&dev_attr_local_ib_port,
	&dev_attr_local_ib_device,
2611
	&dev_attr_comp_vector,
2612
	&dev_attr_tl_retry_count,
2613
	&dev_attr_cmd_sg_entries,
2614
	&dev_attr_allow_ext_sg,
2615 2616 2617
	NULL
};

2618 2619
static struct scsi_host_template srp_template = {
	.module				= THIS_MODULE,
R
Roland Dreier 已提交
2620 2621
	.name				= "InfiniBand SRP initiator",
	.proc_name			= DRV_NAME,
2622
	.slave_configure		= srp_slave_configure,
2623 2624
	.info				= srp_target_info,
	.queuecommand			= srp_queuecommand,
2625
	.change_queue_depth             = srp_change_queue_depth,
2626
	.change_queue_type              = scsi_change_queue_type,
2627 2628 2629
	.eh_abort_handler		= srp_abort,
	.eh_device_reset_handler	= srp_reset_device,
	.eh_host_reset_handler		= srp_reset_host,
B
Bart Van Assche 已提交
2630
	.skip_settle_delay		= true,
2631
	.sg_tablesize			= SRP_DEF_SG_TABLESIZE,
2632
	.can_queue			= SRP_DEFAULT_CMD_SQ_SIZE,
2633
	.this_id			= -1,
2634
	.cmd_per_lun			= SRP_DEFAULT_CMD_SQ_SIZE,
2635 2636
	.use_clustering			= ENABLE_CLUSTERING,
	.shost_attrs			= srp_host_attrs
2637 2638
};

2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649
static int srp_sdev_count(struct Scsi_Host *host)
{
	struct scsi_device *sdev;
	int c = 0;

	shost_for_each_device(sdev, host)
		c++;

	return c;
}

2650 2651
static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
{
2652 2653 2654
	struct srp_rport_identifiers ids;
	struct srp_rport *rport;

2655
	target->state = SRP_TARGET_SCANNING;
2656 2657 2658
	sprintf(target->target_name, "SRP.T10:%016llX",
		 (unsigned long long) be64_to_cpu(target->id_ext));

2659
	if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
2660 2661
		return -ENODEV;

2662 2663
	memcpy(ids.port_id, &target->id_ext, 8);
	memcpy(ids.port_id + 8, &target->ioc_guid, 8);
2664
	ids.roles = SRP_RPORT_ROLE_TARGET;
2665 2666 2667 2668 2669 2670
	rport = srp_rport_add(target->scsi_host, &ids);
	if (IS_ERR(rport)) {
		scsi_remove_host(target->scsi_host);
		return PTR_ERR(rport);
	}

2671
	rport->lld_data = target;
2672
	target->rport = rport;
2673

2674
	spin_lock(&host->target_lock);
2675
	list_add_tail(&target->list, &host->target_list);
2676
	spin_unlock(&host->target_lock);
2677 2678

	scsi_scan_target(&target->scsi_host->shost_gendev,
2679
			 0, target->scsi_id, SCAN_WILD_CARD, 0);
2680

2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697
	if (!target->connected || target->qp_in_error) {
		shost_printk(KERN_INFO, target->scsi_host,
			     PFX "SCSI scan failed - removing SCSI host\n");
		srp_queue_remove_work(target);
		goto out;
	}

	pr_debug(PFX "%s: SCSI scan succeeded - detected %d LUNs\n",
		 dev_name(&target->scsi_host->shost_gendev),
		 srp_sdev_count(target->scsi_host));

	spin_lock_irq(&target->lock);
	if (target->state == SRP_TARGET_SCANNING)
		target->state = SRP_TARGET_LIVE;
	spin_unlock_irq(&target->lock);

out:
2698 2699 2700
	return 0;
}

2701
static void srp_release_dev(struct device *dev)
2702 2703
{
	struct srp_host *host =
2704
		container_of(dev, struct srp_host, dev);
2705 2706 2707 2708 2709 2710

	complete(&host->released);
}

static struct class srp_class = {
	.name    = "infiniband_srp",
2711
	.dev_release = srp_release_dev
2712 2713
};

2714 2715
/**
 * srp_conn_unique() - check whether the connection to a target is unique
2716 2717
 * @host:   SRP host.
 * @target: SRP target port.
2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745
 */
static bool srp_conn_unique(struct srp_host *host,
			    struct srp_target_port *target)
{
	struct srp_target_port *t;
	bool ret = false;

	if (target->state == SRP_TARGET_REMOVED)
		goto out;

	ret = true;

	spin_lock(&host->target_lock);
	list_for_each_entry(t, &host->target_list, list) {
		if (t != target &&
		    target->id_ext == t->id_ext &&
		    target->ioc_guid == t->ioc_guid &&
		    target->initiator_ext == t->initiator_ext) {
			ret = false;
			break;
		}
	}
	spin_unlock(&host->target_lock);

out:
	return ret;
}

2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761
/*
 * 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,
2762
	SRP_OPT_MAX_CMD_PER_LUN	= 1 << 6,
2763
	SRP_OPT_IO_CLASS	= 1 << 7,
2764
	SRP_OPT_INITIATOR_EXT	= 1 << 8,
2765
	SRP_OPT_CMD_SG_ENTRIES	= 1 << 9,
2766 2767
	SRP_OPT_ALLOW_EXT_SG	= 1 << 10,
	SRP_OPT_SG_TABLESIZE	= 1 << 11,
2768
	SRP_OPT_COMP_VECTOR	= 1 << 12,
2769
	SRP_OPT_TL_RETRY_COUNT	= 1 << 13,
2770
	SRP_OPT_QUEUE_SIZE	= 1 << 14,
2771 2772 2773 2774 2775 2776 2777
	SRP_OPT_ALL		= (SRP_OPT_ID_EXT	|
				   SRP_OPT_IOC_GUID	|
				   SRP_OPT_DGID		|
				   SRP_OPT_PKEY		|
				   SRP_OPT_SERVICE_ID),
};

2778
static const match_table_t srp_opt_tokens = {
2779 2780 2781 2782 2783 2784 2785
	{ 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_MAX_CMD_PER_LUN,	"max_cmd_per_lun=%d" 	},
2786
	{ SRP_OPT_IO_CLASS,		"io_class=%x"		},
2787
	{ SRP_OPT_INITIATOR_EXT,	"initiator_ext=%s"	},
2788
	{ SRP_OPT_CMD_SG_ENTRIES,	"cmd_sg_entries=%u"	},
2789 2790
	{ SRP_OPT_ALLOW_EXT_SG,		"allow_ext_sg=%u"	},
	{ SRP_OPT_SG_TABLESIZE,		"sg_tablesize=%u"	},
2791
	{ SRP_OPT_COMP_VECTOR,		"comp_vector=%u"	},
2792
	{ SRP_OPT_TL_RETRY_COUNT,	"tl_retry_count=%u"	},
2793
	{ SRP_OPT_QUEUE_SIZE,		"queue_size=%d"		},
2794
	{ SRP_OPT_ERR,			NULL 			}
2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822
};

static int srp_parse_options(const char *buf, struct srp_target_port *target)
{
	char *options, *sep_opt;
	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;

	sep_opt = options;
	while ((p = strsep(&sep_opt, ",")) != 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);
2823 2824 2825 2826
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
2827 2828 2829 2830 2831 2832
			target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

		case SRP_OPT_IOC_GUID:
			p = match_strdup(args);
2833 2834 2835 2836
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
2837 2838 2839 2840 2841 2842
			target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

		case SRP_OPT_DGID:
			p = match_strdup(args);
2843 2844 2845 2846
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
2847
			if (strlen(p) != 32) {
2848
				pr_warn("bad dest GID parameter '%s'\n", p);
2849
				kfree(p);
2850 2851 2852 2853
				goto out;
			}

			for (i = 0; i < 16; ++i) {
2854 2855 2856 2857 2858 2859 2860
				strlcpy(dgid, p + i * 2, sizeof(dgid));
				if (sscanf(dgid, "%hhx",
					   &target->orig_dgid.raw[i]) < 1) {
					ret = -EINVAL;
					kfree(p);
					goto out;
				}
2861
			}
2862
			kfree(p);
2863 2864 2865 2866
			break;

		case SRP_OPT_PKEY:
			if (match_hex(args, &token)) {
2867
				pr_warn("bad P_Key parameter '%s'\n", p);
2868 2869
				goto out;
			}
2870
			target->pkey = cpu_to_be16(token);
2871 2872 2873 2874
			break;

		case SRP_OPT_SERVICE_ID:
			p = match_strdup(args);
2875 2876 2877 2878
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
2879 2880 2881 2882 2883 2884
			target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

		case SRP_OPT_MAX_SECT:
			if (match_int(args, &token)) {
2885
				pr_warn("bad max sect parameter '%s'\n", p);
2886 2887 2888 2889 2890
				goto out;
			}
			target->scsi_host->max_sectors = token;
			break;

2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902
		case SRP_OPT_QUEUE_SIZE:
			if (match_int(args, &token) || token < 1) {
				pr_warn("bad queue_size parameter '%s'\n", p);
				goto out;
			}
			target->scsi_host->can_queue = token;
			target->queue_size = token + SRP_RSP_SQ_SIZE +
					     SRP_TSK_MGMT_SQ_SIZE;
			if (!(opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
				target->scsi_host->cmd_per_lun = token;
			break;

2903
		case SRP_OPT_MAX_CMD_PER_LUN:
2904
			if (match_int(args, &token) || token < 1) {
2905 2906
				pr_warn("bad max cmd_per_lun parameter '%s'\n",
					p);
2907 2908
				goto out;
			}
2909
			target->scsi_host->cmd_per_lun = token;
2910 2911
			break;

2912 2913
		case SRP_OPT_IO_CLASS:
			if (match_hex(args, &token)) {
2914
				pr_warn("bad IO class parameter '%s'\n", p);
2915 2916 2917 2918
				goto out;
			}
			if (token != SRP_REV10_IB_IO_CLASS &&
			    token != SRP_REV16A_IB_IO_CLASS) {
2919 2920 2921
				pr_warn("unknown IO class parameter value %x specified (use %x or %x).\n",
					token, SRP_REV10_IB_IO_CLASS,
					SRP_REV16A_IB_IO_CLASS);
2922 2923 2924 2925 2926
				goto out;
			}
			target->io_class = token;
			break;

2927 2928
		case SRP_OPT_INITIATOR_EXT:
			p = match_strdup(args);
2929 2930 2931 2932
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
2933 2934 2935 2936
			target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

2937 2938
		case SRP_OPT_CMD_SG_ENTRIES:
			if (match_int(args, &token) || token < 1 || token > 255) {
2939 2940
				pr_warn("bad max cmd_sg_entries parameter '%s'\n",
					p);
2941 2942 2943 2944 2945
				goto out;
			}
			target->cmd_sg_cnt = token;
			break;

2946 2947
		case SRP_OPT_ALLOW_EXT_SG:
			if (match_int(args, &token)) {
2948
				pr_warn("bad allow_ext_sg parameter '%s'\n", p);
2949 2950 2951 2952 2953 2954 2955 2956
				goto out;
			}
			target->allow_ext_sg = !!token;
			break;

		case SRP_OPT_SG_TABLESIZE:
			if (match_int(args, &token) || token < 1 ||
					token > SCSI_MAX_SG_CHAIN_SEGMENTS) {
2957 2958
				pr_warn("bad max sg_tablesize parameter '%s'\n",
					p);
2959 2960 2961 2962 2963
				goto out;
			}
			target->sg_tablesize = token;
			break;

2964 2965 2966 2967 2968 2969 2970 2971
		case SRP_OPT_COMP_VECTOR:
			if (match_int(args, &token) || token < 0) {
				pr_warn("bad comp_vector parameter '%s'\n", p);
				goto out;
			}
			target->comp_vector = token;
			break;

2972 2973 2974 2975 2976 2977 2978 2979 2980
		case SRP_OPT_TL_RETRY_COUNT:
			if (match_int(args, &token) || token < 2 || token > 7) {
				pr_warn("bad tl_retry_count parameter '%s' (must be a number between 2 and 7)\n",
					p);
				goto out;
			}
			target->tl_retry_count = token;
			break;

2981
		default:
2982 2983
			pr_warn("unknown parameter or missing value '%s' in target creation request\n",
				p);
2984 2985 2986 2987 2988 2989 2990 2991 2992 2993
			goto out;
		}
	}

	if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
		ret = 0;
	else
		for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
			if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
			    !(srp_opt_tokens[i].token & opt_mask))
2994 2995
				pr_warn("target creation request is missing parameter '%s'\n",
					srp_opt_tokens[i].pattern);
2996

2997 2998 2999 3000 3001 3002
	if (target->scsi_host->cmd_per_lun > target->scsi_host->can_queue
	    && (opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
		pr_warn("cmd_per_lun = %d > queue_size = %d\n",
			target->scsi_host->cmd_per_lun,
			target->scsi_host->can_queue);

3003 3004 3005 3006 3007
out:
	kfree(options);
	return ret;
}

3008 3009
static ssize_t srp_create_target(struct device *dev,
				 struct device_attribute *attr,
3010 3011 3012
				 const char *buf, size_t count)
{
	struct srp_host *host =
3013
		container_of(dev, struct srp_host, dev);
3014 3015
	struct Scsi_Host *target_host;
	struct srp_target_port *target;
3016
	struct srp_rdma_ch *ch;
3017 3018
	struct srp_device *srp_dev = host->srp_dev;
	struct ib_device *ibdev = srp_dev->dev;
3019
	int ret;
3020 3021 3022 3023 3024 3025

	target_host = scsi_host_alloc(&srp_template,
				      sizeof (struct srp_target_port));
	if (!target_host)
		return -ENOMEM;

3026
	target_host->transportt  = ib_srp_transport_template;
3027 3028
	target_host->max_channel = 0;
	target_host->max_id      = 1;
A
Arne Redlich 已提交
3029 3030
	target_host->max_lun     = SRP_MAX_LUN;
	target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
R
Roland Dreier 已提交
3031

3032 3033
	target = host_to_target(target_host);

3034 3035 3036 3037 3038 3039
	target->io_class	= SRP_REV16A_IB_IO_CLASS;
	target->scsi_host	= target_host;
	target->srp_host	= host;
	target->lkey		= host->srp_dev->mr->lkey;
	target->rkey		= host->srp_dev->mr->rkey;
	target->cmd_sg_cnt	= cmd_sg_entries;
3040 3041
	target->sg_tablesize	= indirect_sg_entries ? : cmd_sg_entries;
	target->allow_ext_sg	= allow_ext_sg;
3042
	target->tl_retry_count	= 7;
3043
	target->queue_size	= SRP_DEFAULT_QUEUE_SIZE;
3044

3045 3046 3047 3048 3049 3050
	/*
	 * Avoid that the SCSI host can be removed by srp_remove_target()
	 * before this function returns.
	 */
	scsi_host_get(target->scsi_host);

3051 3052
	mutex_lock(&host->add_target_mutex);

3053 3054 3055 3056
	ret = srp_parse_options(buf, target);
	if (ret)
		goto err;

3057 3058
	target->req_ring_size = target->queue_size - SRP_TSK_MGMT_SQ_SIZE;

3059 3060 3061 3062 3063 3064 3065 3066 3067 3068
	if (!srp_conn_unique(target->srp_host, target)) {
		shost_printk(KERN_INFO, target->scsi_host,
			     PFX "Already connected to target port with id_ext=%016llx;ioc_guid=%016llx;initiator_ext=%016llx\n",
			     be64_to_cpu(target->id_ext),
			     be64_to_cpu(target->ioc_guid),
			     be64_to_cpu(target->initiator_ext));
		ret = -EEXIST;
		goto err;
	}

3069
	if (!srp_dev->has_fmr && !srp_dev->has_fr && !target->allow_ext_sg &&
3070
	    target->cmd_sg_cnt < target->sg_tablesize) {
3071
		pr_warn("No MR pool and no external indirect descriptors, limiting sg_tablesize to cmd_sg_cnt\n");
3072 3073 3074 3075 3076 3077
		target->sg_tablesize = target->cmd_sg_cnt;
	}

	target_host->sg_tablesize = target->sg_tablesize;
	target->indirect_size = target->sg_tablesize *
				sizeof (struct srp_direct_buf);
3078 3079 3080 3081
	target->max_iu_len = sizeof (struct srp_cmd) +
			     sizeof (struct srp_indirect_buf) +
			     target->cmd_sg_cnt * sizeof (struct srp_direct_buf);

3082
	INIT_WORK(&target->tl_err_work, srp_tl_err_work);
3083
	INIT_WORK(&target->remove_work, srp_remove_work);
3084
	spin_lock_init(&target->lock);
3085 3086 3087 3088 3089 3090
	ch = &target->ch;
	ch->target = target;
	ch->comp_vector = target->comp_vector;
	spin_lock_init(&ch->lock);
	INIT_LIST_HEAD(&ch->free_tx);
	ret = srp_alloc_req_data(ch);
3091 3092
	if (ret)
		goto err_free_mem;
3093

3094
	ret = ib_query_gid(ibdev, host->port, 0, &target->sgid);
3095 3096
	if (ret)
		goto err_free_mem;
3097

3098
	ret = srp_create_ch_ib(ch);
3099
	if (ret)
3100
		goto err_free_mem;
3101

3102
	ret = srp_new_cm_id(ch);
D
David Dillow 已提交
3103
	if (ret)
3104
		goto err_free_ib;
3105

3106
	ret = srp_connect_ch(ch);
3107
	if (ret) {
3108 3109
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "Connection failed\n");
3110
		goto err_free_ib;
3111 3112 3113 3114 3115 3116
	}

	ret = srp_add_target(host, target);
	if (ret)
		goto err_disconnect;

3117 3118 3119 3120 3121
	if (target->state != SRP_TARGET_REMOVED) {
		shost_printk(KERN_DEBUG, target->scsi_host, PFX
			     "new target: id_ext %016llx ioc_guid %016llx pkey %04x service_id %016llx sgid %pI6 dgid %pI6\n",
			     be64_to_cpu(target->id_ext),
			     be64_to_cpu(target->ioc_guid),
3122
			     be16_to_cpu(target->pkey),
3123
			     be64_to_cpu(target->service_id),
3124
			     target->sgid.raw, target->orig_dgid.raw);
3125
	}
B
Bart Van Assche 已提交
3126

3127 3128 3129 3130
	ret = count;

out:
	mutex_unlock(&host->add_target_mutex);
3131 3132 3133

	scsi_host_put(target->scsi_host);

3134
	return ret;
3135 3136 3137 3138

err_disconnect:
	srp_disconnect_target(target);

3139
err_free_ib:
3140
	srp_free_ch_ib(target, ch);
3141

3142
err_free_mem:
3143
	srp_free_req_data(target, ch);
3144

3145 3146
err:
	scsi_host_put(target_host);
3147
	goto out;
3148 3149
}

3150
static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
3151

3152 3153
static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
			  char *buf)
3154
{
3155
	struct srp_host *host = container_of(dev, struct srp_host, dev);
3156

3157
	return sprintf(buf, "%s\n", host->srp_dev->dev->name);
3158 3159
}

3160
static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
3161

3162 3163
static ssize_t show_port(struct device *dev, struct device_attribute *attr,
			 char *buf)
3164
{
3165
	struct srp_host *host = container_of(dev, struct srp_host, dev);
3166 3167 3168 3169

	return sprintf(buf, "%d\n", host->port);
}

3170
static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
3171

3172
static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
3173 3174 3175 3176 3177 3178 3179 3180
{
	struct srp_host *host;

	host = kzalloc(sizeof *host, GFP_KERNEL);
	if (!host)
		return NULL;

	INIT_LIST_HEAD(&host->target_list);
3181
	spin_lock_init(&host->target_lock);
3182
	init_completion(&host->released);
3183
	mutex_init(&host->add_target_mutex);
3184
	host->srp_dev = device;
3185 3186
	host->port = port;

3187 3188
	host->dev.class = &srp_class;
	host->dev.parent = device->dev->dma_device;
3189
	dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
3190

3191
	if (device_register(&host->dev))
3192
		goto free_host;
3193
	if (device_create_file(&host->dev, &dev_attr_add_target))
3194
		goto err_class;
3195
	if (device_create_file(&host->dev, &dev_attr_ibdev))
3196
		goto err_class;
3197
	if (device_create_file(&host->dev, &dev_attr_port))
3198 3199 3200 3201 3202
		goto err_class;

	return host;

err_class:
3203
	device_unregister(&host->dev);
3204

3205
free_host:
3206 3207 3208 3209 3210 3211 3212
	kfree(host);

	return NULL;
}

static void srp_add_one(struct ib_device *device)
{
3213 3214
	struct srp_device *srp_dev;
	struct ib_device_attr *dev_attr;
3215
	struct srp_host *host;
3216 3217
	int mr_page_shift, s, e, p;
	u64 max_pages_per_mr;
3218

3219 3220
	dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
	if (!dev_attr)
3221
		return;
3222

3223
	if (ib_query_device(device, dev_attr)) {
3224
		pr_warn("Query device failed for %s\n", device->name);
3225 3226 3227 3228 3229 3230 3231
		goto free_attr;
	}

	srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
	if (!srp_dev)
		goto free_attr;

3232 3233
	srp_dev->has_fmr = (device->alloc_fmr && device->dealloc_fmr &&
			    device->map_phys_fmr && device->unmap_fmr);
3234 3235 3236 3237 3238 3239 3240
	srp_dev->has_fr = (dev_attr->device_cap_flags &
			   IB_DEVICE_MEM_MGT_EXTENSIONS);
	if (!srp_dev->has_fmr && !srp_dev->has_fr)
		dev_warn(&device->dev, "neither FMR nor FR is supported\n");

	srp_dev->use_fast_reg = (srp_dev->has_fr &&
				 (!srp_dev->has_fmr || prefer_fr));
3241

3242 3243
	/*
	 * Use the smallest page size supported by the HCA, down to a
3244 3245
	 * minimum of 4096 bytes. We're unlikely to build large sglists
	 * out of smaller entries.
3246
	 */
3247 3248 3249 3250 3251 3252 3253
	mr_page_shift		= max(12, ffs(dev_attr->page_size_cap) - 1);
	srp_dev->mr_page_size	= 1 << mr_page_shift;
	srp_dev->mr_page_mask	= ~((u64) srp_dev->mr_page_size - 1);
	max_pages_per_mr	= dev_attr->max_mr_size;
	do_div(max_pages_per_mr, srp_dev->mr_page_size);
	srp_dev->max_pages_per_mr = min_t(u64, SRP_MAX_PAGES_PER_MR,
					  max_pages_per_mr);
3254 3255 3256 3257 3258
	if (srp_dev->use_fast_reg) {
		srp_dev->max_pages_per_mr =
			min_t(u32, srp_dev->max_pages_per_mr,
			      dev_attr->max_fast_reg_page_list_len);
	}
3259 3260
	srp_dev->mr_max_size	= srp_dev->mr_page_size *
				   srp_dev->max_pages_per_mr;
3261
	pr_debug("%s: mr_page_shift = %d, dev_attr->max_mr_size = %#llx, dev_attr->max_fast_reg_page_list_len = %u, max_pages_per_mr = %d, mr_max_size = %#x\n",
3262
		 device->name, mr_page_shift, dev_attr->max_mr_size,
3263
		 dev_attr->max_fast_reg_page_list_len,
3264
		 srp_dev->max_pages_per_mr, srp_dev->mr_max_size);
3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279

	INIT_LIST_HEAD(&srp_dev->dev_list);

	srp_dev->dev = device;
	srp_dev->pd  = ib_alloc_pd(device);
	if (IS_ERR(srp_dev->pd))
		goto free_dev;

	srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
				    IB_ACCESS_LOCAL_WRITE |
				    IB_ACCESS_REMOTE_READ |
				    IB_ACCESS_REMOTE_WRITE);
	if (IS_ERR(srp_dev->mr))
		goto err_pd;

T
Tom Tucker 已提交
3280
	if (device->node_type == RDMA_NODE_IB_SWITCH) {
3281 3282 3283 3284 3285 3286 3287 3288
		s = 0;
		e = 0;
	} else {
		s = 1;
		e = device->phys_port_cnt;
	}

	for (p = s; p <= e; ++p) {
3289
		host = srp_add_port(srp_dev, p);
3290
		if (host)
3291
			list_add_tail(&host->list, &srp_dev->dev_list);
3292 3293
	}

3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305
	ib_set_client_data(device, &srp_client, srp_dev);

	goto free_attr;

err_pd:
	ib_dealloc_pd(srp_dev->pd);

free_dev:
	kfree(srp_dev);

free_attr:
	kfree(dev_attr);
3306 3307 3308 3309
}

static void srp_remove_one(struct ib_device *device)
{
3310
	struct srp_device *srp_dev;
3311
	struct srp_host *host, *tmp_host;
3312
	struct srp_target_port *target;
3313

3314
	srp_dev = ib_get_client_data(device, &srp_client);
3315 3316
	if (!srp_dev)
		return;
3317

3318
	list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
3319
		device_unregister(&host->dev);
3320 3321 3322 3323 3324 3325 3326
		/*
		 * Wait for the sysfs entry to go away, so that no new
		 * target ports can be created.
		 */
		wait_for_completion(&host->released);

		/*
3327
		 * Remove all target ports.
3328
		 */
3329
		spin_lock(&host->target_lock);
3330 3331
		list_for_each_entry(target, &host->target_list, list)
			srp_queue_remove_work(target);
3332
		spin_unlock(&host->target_lock);
3333 3334

		/*
3335
		 * Wait for tl_err and target port removal tasks.
3336
		 */
3337
		flush_workqueue(system_long_wq);
3338
		flush_workqueue(srp_remove_wq);
3339 3340 3341 3342

		kfree(host);
	}

3343 3344 3345 3346
	ib_dereg_mr(srp_dev->mr);
	ib_dealloc_pd(srp_dev->pd);

	kfree(srp_dev);
3347 3348
}

3349
static struct srp_function_template ib_srp_transport_functions = {
3350 3351
	.has_rport_state	 = true,
	.reset_timer_if_blocked	 = true,
3352
	.reconnect_delay	 = &srp_reconnect_delay,
3353 3354 3355
	.fast_io_fail_tmo	 = &srp_fast_io_fail_tmo,
	.dev_loss_tmo		 = &srp_dev_loss_tmo,
	.reconnect		 = srp_rport_reconnect,
3356
	.rport_delete		 = srp_rport_delete,
3357
	.terminate_rport_io	 = srp_terminate_io,
3358 3359
};

3360 3361 3362 3363
static int __init srp_init_module(void)
{
	int ret;

3364
	BUILD_BUG_ON(FIELD_SIZEOF(struct ib_wc, wr_id) < sizeof(void *));
3365

3366
	if (srp_sg_tablesize) {
3367
		pr_warn("srp_sg_tablesize is deprecated, please use cmd_sg_entries\n");
3368 3369 3370 3371 3372 3373 3374 3375
		if (!cmd_sg_entries)
			cmd_sg_entries = srp_sg_tablesize;
	}

	if (!cmd_sg_entries)
		cmd_sg_entries = SRP_DEF_SG_TABLESIZE;

	if (cmd_sg_entries > 255) {
3376
		pr_warn("Clamping cmd_sg_entries to 255\n");
3377
		cmd_sg_entries = 255;
3378 3379
	}

3380 3381 3382
	if (!indirect_sg_entries)
		indirect_sg_entries = cmd_sg_entries;
	else if (indirect_sg_entries < cmd_sg_entries) {
3383 3384
		pr_warn("Bumping up indirect_sg_entries to match cmd_sg_entries (%u)\n",
			cmd_sg_entries);
3385 3386 3387
		indirect_sg_entries = cmd_sg_entries;
	}

3388
	srp_remove_wq = create_workqueue("srp_remove");
3389 3390
	if (!srp_remove_wq) {
		ret = -ENOMEM;
3391 3392 3393 3394
		goto out;
	}

	ret = -ENOMEM;
3395 3396 3397
	ib_srp_transport_template =
		srp_attach_transport(&ib_srp_transport_functions);
	if (!ib_srp_transport_template)
3398
		goto destroy_wq;
3399

3400 3401
	ret = class_register(&srp_class);
	if (ret) {
3402
		pr_err("couldn't register class infiniband_srp\n");
3403
		goto release_tr;
3404 3405
	}

3406 3407
	ib_sa_register_client(&srp_sa_client);

3408 3409
	ret = ib_register_client(&srp_client);
	if (ret) {
3410
		pr_err("couldn't register IB client\n");
3411
		goto unreg_sa;
3412 3413
	}

3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426
out:
	return ret;

unreg_sa:
	ib_sa_unregister_client(&srp_sa_client);
	class_unregister(&srp_class);

release_tr:
	srp_release_transport(ib_srp_transport_template);

destroy_wq:
	destroy_workqueue(srp_remove_wq);
	goto out;
3427 3428 3429 3430 3431
}

static void __exit srp_cleanup_module(void)
{
	ib_unregister_client(&srp_client);
3432
	ib_sa_unregister_client(&srp_sa_client);
3433
	class_unregister(&srp_class);
3434
	srp_release_transport(ib_srp_transport_template);
3435
	destroy_workqueue(srp_remove_wq);
3436 3437 3438 3439
}

module_init(srp_init_module);
module_exit(srp_cleanup_module);