ib_srp.c 99.4 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/lockdep.h>
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#include <rdma/ib_cache.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	"2.0"
#define DRV_RELDATE	"July 26, 2015"
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MODULE_AUTHOR("Roland Dreier");
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MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator");
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MODULE_LICENSE("Dual BSD/GPL");
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MODULE_INFO(release_date, DRV_RELDATE);
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#if !defined(CONFIG_DYNAMIC_DEBUG)
#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt)
#define DYNAMIC_DEBUG_BRANCH(descriptor) false
#endif

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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 = true;
static bool register_always = true;
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static bool never_register;
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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,
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		 "Default max number of gather/scatter entries (default is 12, max is " __stringify(SG_MAX_SEGMENTS) ")");
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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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module_param(never_register, bool, 0444);
MODULE_PARM_DESC(never_register, "Never register memory");

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static const 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 unsigned ch_count;
module_param(ch_count, uint, 0444);
MODULE_PARM_DESC(ch_count,
		 "Number of RDMA channels to use for communication with an SRP target. Using more than one channel improves performance if the HCA supports multiple completion vectors. The default value is the minimum of four times the number of online CPU sockets and the number of completion vectors supported by the HCA.");

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static void srp_add_one(struct ib_device *device);
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static void srp_remove_one(struct ib_device *device, void *client_data);
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static void srp_recv_done(struct ib_cq *cq, struct ib_wc *wc);
static void srp_handle_qp_err(struct ib_cq *cq, struct ib_wc *wc,
		const char *opname);
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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;

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	res = srp_parse_tmo(&tmo, val);
	if (res)
		goto out;

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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;
}

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static const struct kernel_param_ops srp_tmo_ops = {
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	.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 %s (%d)\n",
		 ib_event_msg(event->event), 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_cached_pkey(target->srp_host->srp_dev->dev,
				  target->srp_host->port,
				  be16_to_cpu(target->pkey),
				  &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;
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	if (rdma_cap_opa_ah(target->srp_host->srp_dev->dev,
			    target->srp_host->port))
		ch->path.rec_type = SA_PATH_REC_TYPE_OPA;
	else
		ch->path.rec_type = SA_PATH_REC_TYPE_IB;
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	ch->path.sgid = target->sgid;
	ch->path.dgid = target->orig_dgid;
	ch->path.pkey = target->pkey;
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	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));
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	fmr_param.pool_size	    = target->mr_pool_size;
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	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->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;
	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++) {
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		mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG,
				 max_page_list_len);
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		if (IS_ERR(mr)) {
			ret = PTR_ERR(mr);
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			if (ret == -ENOMEM)
				pr_info("%s: ib_alloc_mr() failed. Try to reduce max_cmd_per_lun, max_sect or ch_count\n",
					dev_name(&device->dev));
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			goto destroy_pool;
		}
		d->mr = mr;
		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;

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

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/**
 * srp_destroy_qp() - destroy an RDMA queue pair
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 * @ch: SRP RDMA channel.
468
 *
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 * Drain the qp before destroying it.  This avoids that the receive
 * completion handler can access the queue pair while it is
471 472
 * being destroyed.
 */
473
static void srp_destroy_qp(struct srp_rdma_ch *ch)
474
{
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	spin_lock_irq(&ch->lock);
	ib_process_cq_direct(ch->send_cq, -1);
	spin_unlock_irq(&ch->lock);

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	ib_drain_qp(ch->qp);
	ib_destroy_qp(ch->qp);
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}

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static int srp_create_ch_ib(struct srp_rdma_ch *ch)
484
{
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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;
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	const int m = 1 + dev->use_fast_reg * target->mr_per_cmd * 2;
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	int ret;

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

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	/* queue_size + 1 for ib_drain_rq() */
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	recv_cq = ib_alloc_cq(dev->dev, ch, target->queue_size + 1,
				ch->comp_vector, IB_POLL_SOFTIRQ);
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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_alloc_cq(dev->dev, ch, m * target->queue_size,
				ch->comp_vector, IB_POLL_DIRECT);
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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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	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 + 1;
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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) {
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		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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	} else if (dev->use_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->qp)
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		srp_destroy_qp(ch);
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	if (ch->recv_cq)
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		ib_free_cq(ch->recv_cq);
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	if (ch->send_cq)
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		ib_free_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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	if (dev->use_fast_reg) {
		if (ch->fr_pool)
			srp_destroy_fr_pool(ch->fr_pool);
		ch->fr_pool = fr_pool;
	} else if (dev->use_fmr) {
		if (ch->fmr_pool)
			ib_destroy_fmr_pool(ch->fmr_pool);
		ch->fmr_pool = fmr_pool;
	}

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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_free_cq(send_cq);
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err_recv_cq:
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	ib_free_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
592
 * invoked. Hence the ch->[rt]x_ring checks.
593
 */
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static void srp_free_ch_ib(struct srp_target_port *target,
			   struct srp_rdma_ch *ch)
596
{
597
	struct srp_device *dev = target->srp_host->srp_dev;
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	int i;

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	if (!ch->target)
		return;

603 604 605
	if (ch->cm_id) {
		ib_destroy_cm_id(ch->cm_id);
		ch->cm_id = NULL;
606 607
	}

B
Bart Van Assche 已提交
608 609 610 611
	/* If srp_new_cm_id() succeeded but srp_create_ch_ib() not, return. */
	if (!ch->qp)
		return;

612
	if (dev->use_fast_reg) {
613 614
		if (ch->fr_pool)
			srp_destroy_fr_pool(ch->fr_pool);
615
	} else if (dev->use_fmr) {
616 617
		if (ch->fmr_pool)
			ib_destroy_fmr_pool(ch->fmr_pool);
618
	}
C
Christoph Hellwig 已提交
619

620
	srp_destroy_qp(ch);
C
Christoph Hellwig 已提交
621 622
	ib_free_cq(ch->send_cq);
	ib_free_cq(ch->recv_cq);
623

B
Bart Van Assche 已提交
624 625 626 627 628 629 630 631
	/*
	 * Avoid that the SCSI error handler tries to use this channel after
	 * it has been freed. The SCSI error handler can namely continue
	 * trying to perform recovery actions after scsi_remove_host()
	 * returned.
	 */
	ch->target = NULL;

632 633
	ch->qp = NULL;
	ch->send_cq = ch->recv_cq = NULL;
634

635
	if (ch->rx_ring) {
636
		for (i = 0; i < target->queue_size; ++i)
637 638 639
			srp_free_iu(target->srp_host, ch->rx_ring[i]);
		kfree(ch->rx_ring);
		ch->rx_ring = NULL;
640
	}
641
	if (ch->tx_ring) {
642
		for (i = 0; i < target->queue_size; ++i)
643 644 645
			srp_free_iu(target->srp_host, ch->tx_ring[i]);
		kfree(ch->tx_ring);
		ch->tx_ring = NULL;
646
	}
647 648 649
}

static void srp_path_rec_completion(int status,
650
				    struct sa_path_rec *pathrec,
651
				    void *ch_ptr)
652
{
653 654
	struct srp_rdma_ch *ch = ch_ptr;
	struct srp_target_port *target = ch->target;
655

656
	ch->status = status;
657
	if (status)
658 659
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "Got failed path rec status %d\n", status);
660
	else
661 662
		ch->path = *pathrec;
	complete(&ch->done);
663 664
}

665
static int srp_lookup_path(struct srp_rdma_ch *ch)
666
{
667
	struct srp_target_port *target = ch->target;
668
	int ret = -ENODEV;
669

670 671 672 673
	ch->path.numb_path = 1;

	init_completion(&ch->done);

674 675 676 677 678 679 680
	/*
	 * Avoid that the SCSI host can be removed by srp_remove_target()
	 * before srp_path_rec_completion() is called.
	 */
	if (!scsi_host_get(target->scsi_host))
		goto out;

681 682 683 684 685 686 687 688 689 690 691 692 693
	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);
694 695 696
	ret = ch->path_query_id;
	if (ret < 0)
		goto put;
697 698

	ret = wait_for_completion_interruptible(&ch->done);
699
	if (ret < 0)
700
		goto put;
701

702 703
	ret = ch->status;
	if (ret < 0)
704 705
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Path record query failed\n");
706

707 708 709 710 711
put:
	scsi_host_put(target->scsi_host);

out:
	return ret;
712 713
}

B
Bart Van Assche 已提交
714
static int srp_send_req(struct srp_rdma_ch *ch, bool multich)
715
{
716
	struct srp_target_port *target = ch->target;
717 718 719 720 721 722 723 724 725 726
	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;

727
	req->param.primary_path		      = &ch->path;
728 729
	req->param.alternate_path 	      = NULL;
	req->param.service_id 		      = target->service_id;
730 731
	req->param.qp_num		      = ch->qp->qp_num;
	req->param.qp_type		      = ch->qp->qp_type;
732 733 734 735 736 737 738 739 740 741 742 743 744 745
	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;
746
	req->param.retry_count                = target->tl_retry_count;
747 748 749 750 751
	req->param.rnr_retry_count 	      = 7;
	req->param.max_cm_retries 	      = 15;

	req->priv.opcode     	= SRP_LOGIN_REQ;
	req->priv.tag        	= 0;
752
	req->priv.req_it_iu_len = cpu_to_be32(target->max_iu_len);
753 754
	req->priv.req_buf_fmt 	= cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
					      SRP_BUF_FORMAT_INDIRECT);
B
Bart Van Assche 已提交
755 756
	req->priv.req_flags	= (multich ? SRP_MULTICHAN_MULTI :
				   SRP_MULTICHAN_SINGLE);
757
	/*
R
Roland Dreier 已提交
758
	 * In the published SRP specification (draft rev. 16a), the
759 760 761 762 763 764 765 766 767
	 * 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,
768
		       &target->sgid.global.interface_id, 8);
769
		memcpy(req->priv.initiator_port_id + 8,
770
		       &target->initiator_ext, 8);
771 772 773 774
		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,
775 776
		       &target->initiator_ext, 8);
		memcpy(req->priv.initiator_port_id + 8,
777
		       &target->sgid.global.interface_id, 8);
778 779 780 781
		memcpy(req->priv.target_port_id,     &target->id_ext, 8);
		memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
	}

782 783
	/*
	 * Topspin/Cisco SRP targets will reject our login unless we
784 785
	 * zero out the first 8 bytes of our initiator port ID and set
	 * the second 8 bytes to the local node GUID.
786
	 */
787
	if (srp_target_is_topspin(target)) {
788 789 790
		shost_printk(KERN_DEBUG, target->scsi_host,
			     PFX "Topspin/Cisco initiator port ID workaround "
			     "activated for target GUID %016llx\n",
791
			     be64_to_cpu(target->ioc_guid));
792
		memset(req->priv.initiator_port_id, 0, 8);
793
		memcpy(req->priv.initiator_port_id + 8,
794
		       &target->srp_host->srp_dev->dev->node_guid, 8);
795 796
	}

797
	status = ib_send_cm_req(ch->cm_id, &req->param);
798 799 800 801 802 803

	kfree(req);

	return status;
}

804 805 806 807 808 809 810 811 812 813 814 815
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)
816
		queue_work(srp_remove_wq, &target->remove_work);
817 818 819 820

	return changed;
}

821 822
static void srp_disconnect_target(struct srp_target_port *target)
{
B
Bart Van Assche 已提交
823 824
	struct srp_rdma_ch *ch;
	int i;
825

826
	/* XXX should send SRP_I_LOGOUT request */
827

828 829 830 831 832 833
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		ch->connected = false;
		if (ch->cm_id && ib_send_cm_dreq(ch->cm_id, NULL, 0)) {
			shost_printk(KERN_DEBUG, target->scsi_host,
				     PFX "Sending CM DREQ failed\n");
834
		}
835
	}
836 837
}

838 839
static void srp_free_req_data(struct srp_target_port *target,
			      struct srp_rdma_ch *ch)
840
{
841 842
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
843 844 845
	struct srp_request *req;
	int i;

846
	if (!ch->req_ring)
847 848 849
		return;

	for (i = 0; i < target->req_ring_size; ++i) {
850
		req = &ch->req_ring[i];
851
		if (dev->use_fast_reg) {
852
			kfree(req->fr_list);
853
		} else {
854
			kfree(req->fmr_list);
855 856
			kfree(req->map_page);
		}
857 858 859 860 861 862
		if (req->indirect_dma_addr) {
			ib_dma_unmap_single(ibdev, req->indirect_dma_addr,
					    target->indirect_size,
					    DMA_TO_DEVICE);
		}
		kfree(req->indirect_desc);
863
	}
864

865 866
	kfree(ch->req_ring);
	ch->req_ring = NULL;
867 868
}

869
static int srp_alloc_req_data(struct srp_rdma_ch *ch)
870
{
871
	struct srp_target_port *target = ch->target;
872 873 874
	struct srp_device *srp_dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = srp_dev->dev;
	struct srp_request *req;
875
	void *mr_list;
876 877 878
	dma_addr_t dma_addr;
	int i, ret = -ENOMEM;

879 880 881
	ch->req_ring = kcalloc(target->req_ring_size, sizeof(*ch->req_ring),
			       GFP_KERNEL);
	if (!ch->req_ring)
882 883 884
		goto out;

	for (i = 0; i < target->req_ring_size; ++i) {
885
		req = &ch->req_ring[i];
886
		mr_list = kmalloc(target->mr_per_cmd * sizeof(void *),
887 888 889
				  GFP_KERNEL);
		if (!mr_list)
			goto out;
890
		if (srp_dev->use_fast_reg) {
891
			req->fr_list = mr_list;
892
		} else {
893
			req->fmr_list = mr_list;
894 895 896 897 898
			req->map_page = kmalloc(srp_dev->max_pages_per_mr *
						sizeof(void *), GFP_KERNEL);
			if (!req->map_page)
				goto out;
		}
899
		req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
900
		if (!req->indirect_desc)
901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916
			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;
	}
	ret = 0;

out:
	return ret;
}

917 918 919 920 921 922 923 924 925 926 927 928 929 930 931
/**
 * 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);
}

932 933
static void srp_remove_target(struct srp_target_port *target)
{
B
Bart Van Assche 已提交
934 935
	struct srp_rdma_ch *ch;
	int i;
936

937 938
	WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);

939
	srp_del_scsi_host_attr(target->scsi_host);
940
	srp_rport_get(target->rport);
941 942
	srp_remove_host(target->scsi_host);
	scsi_remove_host(target->scsi_host);
943
	srp_stop_rport_timers(target->rport);
944
	srp_disconnect_target(target);
B
Bart Van Assche 已提交
945 946 947 948
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		srp_free_ch_ib(target, ch);
	}
949
	cancel_work_sync(&target->tl_err_work);
950
	srp_rport_put(target->rport);
B
Bart Van Assche 已提交
951 952 953 954 955 956
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		srp_free_req_data(target, ch);
	}
	kfree(target->ch);
	target->ch = NULL;
957 958 959 960 961

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

962 963 964
	scsi_host_put(target->scsi_host);
}

D
David Howells 已提交
965
static void srp_remove_work(struct work_struct *work)
966
{
D
David Howells 已提交
967
	struct srp_target_port *target =
968
		container_of(work, struct srp_target_port, remove_work);
969

970
	WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
971

972
	srp_remove_target(target);
973 974
}

975 976 977 978 979 980 981
static void srp_rport_delete(struct srp_rport *rport)
{
	struct srp_target_port *target = rport->lld_data;

	srp_queue_remove_work(target);
}

982 983 984 985 986 987 988 989 990 991 992 993 994 995
/**
 * srp_connected_ch() - number of connected channels
 * @target: SRP target port.
 */
static int srp_connected_ch(struct srp_target_port *target)
{
	int i, c = 0;

	for (i = 0; i < target->ch_count; i++)
		c += target->ch[i].connected;

	return c;
}

B
Bart Van Assche 已提交
996
static int srp_connect_ch(struct srp_rdma_ch *ch, bool multich)
997
{
998
	struct srp_target_port *target = ch->target;
999 1000
	int ret;

1001
	WARN_ON_ONCE(!multich && srp_connected_ch(target) > 0);
1002

1003
	ret = srp_lookup_path(ch);
1004
	if (ret)
B
Bart Van Assche 已提交
1005
		goto out;
1006 1007

	while (1) {
1008
		init_completion(&ch->done);
B
Bart Van Assche 已提交
1009
		ret = srp_send_req(ch, multich);
1010
		if (ret)
B
Bart Van Assche 已提交
1011
			goto out;
1012
		ret = wait_for_completion_interruptible(&ch->done);
1013
		if (ret < 0)
B
Bart Van Assche 已提交
1014
			goto out;
1015 1016 1017 1018 1019 1020 1021

		/*
		 * 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.
		 */
B
Bart Van Assche 已提交
1022 1023
		ret = ch->status;
		switch (ret) {
1024
		case 0:
1025
			ch->connected = true;
B
Bart Van Assche 已提交
1026
			goto out;
1027 1028

		case SRP_PORT_REDIRECT:
1029
			ret = srp_lookup_path(ch);
1030
			if (ret)
B
Bart Van Assche 已提交
1031
				goto out;
1032 1033 1034 1035 1036
			break;

		case SRP_DLID_REDIRECT:
			break;

D
David Dillow 已提交
1037 1038
		case SRP_STALE_CONN:
			shost_printk(KERN_ERR, target->scsi_host, PFX
1039
				     "giving up on stale connection\n");
B
Bart Van Assche 已提交
1040 1041
			ret = -ECONNRESET;
			goto out;
D
David Dillow 已提交
1042

1043
		default:
B
Bart Van Assche 已提交
1044
			goto out;
1045 1046
		}
	}
B
Bart Van Assche 已提交
1047 1048 1049

out:
	return ret <= 0 ? ret : -ENODEV;
1050 1051
}

C
Christoph Hellwig 已提交
1052 1053 1054 1055 1056 1057 1058
static void srp_inv_rkey_err_done(struct ib_cq *cq, struct ib_wc *wc)
{
	srp_handle_qp_err(cq, wc, "INV RKEY");
}

static int srp_inv_rkey(struct srp_request *req, struct srp_rdma_ch *ch,
		u32 rkey)
1059 1060 1061 1062 1063 1064 1065 1066 1067 1068
{
	struct ib_send_wr *bad_wr;
	struct ib_send_wr wr = {
		.opcode		    = IB_WR_LOCAL_INV,
		.next		    = NULL,
		.num_sge	    = 0,
		.send_flags	    = 0,
		.ex.invalidate_rkey = rkey,
	};

C
Christoph Hellwig 已提交
1069 1070
	wr.wr_cqe = &req->reg_cqe;
	req->reg_cqe.done = srp_inv_rkey_err_done;
1071
	return ib_post_send(ch->qp, &wr, &bad_wr);
1072 1073
}

1074
static void srp_unmap_data(struct scsi_cmnd *scmnd,
1075
			   struct srp_rdma_ch *ch,
1076 1077
			   struct srp_request *req)
{
1078
	struct srp_target_port *target = ch->target;
1079 1080 1081
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
	int i, res;
1082

1083
	if (!scsi_sglist(scmnd) ||
1084 1085 1086 1087
	    (scmnd->sc_data_direction != DMA_TO_DEVICE &&
	     scmnd->sc_data_direction != DMA_FROM_DEVICE))
		return;

1088 1089 1090 1091
	if (dev->use_fast_reg) {
		struct srp_fr_desc **pfr;

		for (i = req->nmdesc, pfr = req->fr_list; i > 0; i--, pfr++) {
C
Christoph Hellwig 已提交
1092
			res = srp_inv_rkey(req, ch, (*pfr)->mr->rkey);
1093 1094 1095 1096 1097 1098 1099 1100 1101
			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)
1102
			srp_fr_pool_put(ch->fr_pool, req->fr_list,
1103
					req->nmdesc);
1104
	} else if (dev->use_fmr) {
1105 1106 1107 1108 1109
		struct ib_pool_fmr **pfmr;

		for (i = req->nmdesc, pfmr = req->fmr_list; i > 0; i--, pfmr++)
			ib_fmr_pool_unmap(*pfmr);
	}
1110

1111 1112
	ib_dma_unmap_sg(ibdev, scsi_sglist(scmnd), scsi_sg_count(scmnd),
			scmnd->sc_data_direction);
1113 1114
}

B
Bart Van Assche 已提交
1115 1116
/**
 * srp_claim_req - Take ownership of the scmnd associated with a request.
1117
 * @ch: SRP RDMA channel.
B
Bart Van Assche 已提交
1118
 * @req: SRP request.
1119
 * @sdev: If not NULL, only take ownership for this SCSI device.
B
Bart Van Assche 已提交
1120 1121 1122 1123 1124 1125
 * @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.
 */
1126
static struct scsi_cmnd *srp_claim_req(struct srp_rdma_ch *ch,
B
Bart Van Assche 已提交
1127
				       struct srp_request *req,
1128
				       struct scsi_device *sdev,
B
Bart Van Assche 已提交
1129 1130 1131 1132
				       struct scsi_cmnd *scmnd)
{
	unsigned long flags;

1133
	spin_lock_irqsave(&ch->lock, flags);
1134 1135 1136
	if (req->scmnd &&
	    (!sdev || req->scmnd->device == sdev) &&
	    (!scmnd || req->scmnd == scmnd)) {
B
Bart Van Assche 已提交
1137 1138 1139 1140 1141
		scmnd = req->scmnd;
		req->scmnd = NULL;
	} else {
		scmnd = NULL;
	}
1142
	spin_unlock_irqrestore(&ch->lock, flags);
B
Bart Van Assche 已提交
1143 1144 1145 1146 1147

	return scmnd;
}

/**
B
Bart Van Assche 已提交
1148
 * srp_free_req() - Unmap data and adjust ch->req_lim.
1149
 * @ch:     SRP RDMA channel.
1150 1151 1152
 * @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
1153
 */
1154 1155
static void srp_free_req(struct srp_rdma_ch *ch, struct srp_request *req,
			 struct scsi_cmnd *scmnd, s32 req_lim_delta)
1156
{
1157 1158
	unsigned long flags;

1159
	srp_unmap_data(scmnd, ch, req);
B
Bart Van Assche 已提交
1160

1161 1162 1163
	spin_lock_irqsave(&ch->lock, flags);
	ch->req_lim += req_lim_delta;
	spin_unlock_irqrestore(&ch->lock, flags);
1164 1165
}

1166 1167
static void srp_finish_req(struct srp_rdma_ch *ch, struct srp_request *req,
			   struct scsi_device *sdev, int result)
1168
{
1169
	struct scsi_cmnd *scmnd = srp_claim_req(ch, req, sdev, NULL);
B
Bart Van Assche 已提交
1170 1171

	if (scmnd) {
1172
		srp_free_req(ch, req, scmnd, 0);
1173
		scmnd->result = result;
B
Bart Van Assche 已提交
1174 1175
		scmnd->scsi_done(scmnd);
	}
1176 1177
}

1178
static void srp_terminate_io(struct srp_rport *rport)
1179
{
1180
	struct srp_target_port *target = rport->lld_data;
B
Bart Van Assche 已提交
1181
	struct srp_rdma_ch *ch;
1182 1183
	struct Scsi_Host *shost = target->scsi_host;
	struct scsi_device *sdev;
B
Bart Van Assche 已提交
1184
	int i, j;
1185

1186 1187 1188 1189 1190 1191 1192
	/*
	 * 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);

B
Bart Van Assche 已提交
1193 1194
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
1195

B
Bart Van Assche 已提交
1196 1197 1198 1199 1200 1201
		for (j = 0; j < target->req_ring_size; ++j) {
			struct srp_request *req = &ch->req_ring[j];

			srp_finish_req(ch, req, NULL,
				       DID_TRANSPORT_FAILFAST << 16);
		}
1202 1203
	}
}
1204

1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216
/*
 * 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;
B
Bart Van Assche 已提交
1217 1218 1219
	struct srp_rdma_ch *ch;
	int i, j, ret = 0;
	bool multich = false;
1220

1221
	srp_disconnect_target(target);
1222 1223 1224 1225

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

1226
	/*
1227 1228 1229
	 * 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.
1230
	 */
B
Bart Van Assche 已提交
1231 1232 1233
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		ret += srp_new_cm_id(ch);
1234
	}
B
Bart Van Assche 已提交
1235 1236 1237 1238
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		for (j = 0; j < target->req_ring_size; ++j) {
			struct srp_request *req = &ch->req_ring[j];
1239

B
Bart Van Assche 已提交
1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250
			srp_finish_req(ch, req, NULL, DID_RESET << 16);
		}
	}
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		/*
		 * Whether or not creating a new CM ID succeeded, create a new
		 * QP. This guarantees that all completion callback function
		 * invocations have finished before request resetting starts.
		 */
		ret += srp_create_ch_ib(ch);
1251

B
Bart Van Assche 已提交
1252 1253 1254 1255
		INIT_LIST_HEAD(&ch->free_tx);
		for (j = 0; j < target->queue_size; ++j)
			list_add(&ch->tx_ring[j]->list, &ch->free_tx);
	}
1256 1257 1258

	target->qp_in_error = false;

B
Bart Van Assche 已提交
1259 1260
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
1261
		if (ret)
B
Bart Van Assche 已提交
1262 1263 1264 1265
			break;
		ret = srp_connect_ch(ch, multich);
		multich = true;
	}
1266

1267 1268 1269
	if (ret == 0)
		shost_printk(KERN_INFO, target->scsi_host,
			     PFX "reconnect succeeded\n");
1270 1271 1272 1273

	return ret;
}

1274 1275
static void srp_map_desc(struct srp_map_state *state, dma_addr_t dma_addr,
			 unsigned int dma_len, u32 rkey)
1276
{
1277
	struct srp_direct_buf *desc = state->desc;
1278

1279 1280
	WARN_ON_ONCE(!dma_len);

1281 1282 1283
	desc->va = cpu_to_be64(dma_addr);
	desc->key = cpu_to_be32(rkey);
	desc->len = cpu_to_be32(dma_len);
1284

1285 1286 1287 1288
	state->total_len += dma_len;
	state->desc++;
	state->ndesc++;
}
1289

1290
static int srp_map_finish_fmr(struct srp_map_state *state,
1291
			      struct srp_rdma_ch *ch)
1292
{
1293 1294
	struct srp_target_port *target = ch->target;
	struct srp_device *dev = target->srp_host->srp_dev;
1295
	struct ib_pd *pd = target->pd;
1296 1297
	struct ib_pool_fmr *fmr;
	u64 io_addr = 0;
1298

1299 1300 1301 1302
	if (state->fmr.next >= state->fmr.end) {
		shost_printk(KERN_ERR, ch->target->scsi_host,
			     PFX "Out of MRs (mr_per_cmd = %d)\n",
			     ch->target->mr_per_cmd);
1303
		return -ENOMEM;
1304
	}
1305

S
Sagi Grimberg 已提交
1306 1307 1308 1309 1310
	WARN_ON_ONCE(!dev->use_fmr);

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

1311
	if (state->npages == 1 && (pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) {
S
Sagi Grimberg 已提交
1312
		srp_map_desc(state, state->base_dma_addr, state->dma_len,
1313
			     pd->unsafe_global_rkey);
S
Sagi Grimberg 已提交
1314 1315 1316
		goto reset_state;
	}

1317
	fmr = ib_fmr_pool_map_phys(ch->fmr_pool, state->pages,
1318 1319 1320
				   state->npages, io_addr);
	if (IS_ERR(fmr))
		return PTR_ERR(fmr);
1321

1322
	*state->fmr.next++ = fmr;
1323
	state->nmdesc++;
1324

1325 1326
	srp_map_desc(state, state->base_dma_addr & ~dev->mr_page_mask,
		     state->dma_len, fmr->fmr->rkey);
1327

S
Sagi Grimberg 已提交
1328 1329 1330 1331
reset_state:
	state->npages = 0;
	state->dma_len = 0;

1332 1333 1334
	return 0;
}

C
Christoph Hellwig 已提交
1335 1336 1337 1338 1339
static void srp_reg_mr_err_done(struct ib_cq *cq, struct ib_wc *wc)
{
	srp_handle_qp_err(cq, wc, "FAST REG");
}

1340 1341 1342 1343 1344 1345
/*
 * Map up to sg_nents elements of state->sg where *sg_offset_p is the offset
 * where to start in the first element. If sg_offset_p != NULL then
 * *sg_offset_p is updated to the offset in state->sg[retval] of the first
 * byte that has not yet been mapped.
 */
1346
static int srp_map_finish_fr(struct srp_map_state *state,
C
Christoph Hellwig 已提交
1347
			     struct srp_request *req,
1348 1349
			     struct srp_rdma_ch *ch, int sg_nents,
			     unsigned int *sg_offset_p)
1350
{
1351
	struct srp_target_port *target = ch->target;
1352
	struct srp_device *dev = target->srp_host->srp_dev;
1353
	struct ib_pd *pd = target->pd;
1354
	struct ib_send_wr *bad_wr;
1355
	struct ib_reg_wr wr;
1356 1357
	struct srp_fr_desc *desc;
	u32 rkey;
1358
	int n, err;
1359

1360 1361 1362 1363
	if (state->fr.next >= state->fr.end) {
		shost_printk(KERN_ERR, ch->target->scsi_host,
			     PFX "Out of MRs (mr_per_cmd = %d)\n",
			     ch->target->mr_per_cmd);
1364
		return -ENOMEM;
1365
	}
1366

S
Sagi Grimberg 已提交
1367 1368
	WARN_ON_ONCE(!dev->use_fast_reg);

1369
	if (sg_nents == 1 && (pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) {
1370 1371 1372 1373
		unsigned int sg_offset = sg_offset_p ? *sg_offset_p : 0;

		srp_map_desc(state, sg_dma_address(state->sg) + sg_offset,
			     sg_dma_len(state->sg) - sg_offset,
1374
			     pd->unsafe_global_rkey);
1375 1376
		if (sg_offset_p)
			*sg_offset_p = 0;
1377
		return 1;
S
Sagi Grimberg 已提交
1378 1379
	}

1380
	desc = srp_fr_pool_get(ch->fr_pool);
1381 1382 1383 1384 1385 1386
	if (!desc)
		return -ENOMEM;

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

1387 1388
	n = ib_map_mr_sg(desc->mr, state->sg, sg_nents, sg_offset_p,
			 dev->mr_page_size);
1389 1390
	if (unlikely(n < 0)) {
		srp_fr_pool_put(ch->fr_pool, &desc, 1);
1391
		pr_debug("%s: ib_map_mr_sg(%d, %d) returned %d.\n",
1392
			 dev_name(&req->scmnd->device->sdev_gendev), sg_nents,
1393
			 sg_offset_p ? *sg_offset_p : -1, n);
1394
		return n;
1395
	}
1396

1397
	WARN_ON_ONCE(desc->mr->length == 0);
1398

C
Christoph Hellwig 已提交
1399 1400
	req->reg_cqe.done = srp_reg_mr_err_done;

1401 1402
	wr.wr.next = NULL;
	wr.wr.opcode = IB_WR_REG_MR;
C
Christoph Hellwig 已提交
1403
	wr.wr.wr_cqe = &req->reg_cqe;
1404 1405 1406 1407 1408 1409 1410
	wr.wr.num_sge = 0;
	wr.wr.send_flags = 0;
	wr.mr = desc->mr;
	wr.key = desc->mr->rkey;
	wr.access = (IB_ACCESS_LOCAL_WRITE |
		     IB_ACCESS_REMOTE_READ |
		     IB_ACCESS_REMOTE_WRITE);
1411

1412
	*state->fr.next++ = desc;
1413 1414
	state->nmdesc++;

1415 1416
	srp_map_desc(state, desc->mr->iova,
		     desc->mr->length, desc->mr->rkey);
1417

S
Sagi Grimberg 已提交
1418
	err = ib_post_send(ch->qp, &wr.wr, &bad_wr);
1419 1420
	if (unlikely(err)) {
		WARN_ON_ONCE(err == -ENOMEM);
S
Sagi Grimberg 已提交
1421
		return err;
1422
	}
S
Sagi Grimberg 已提交
1423

1424
	return n;
1425 1426
}

1427
static int srp_map_sg_entry(struct srp_map_state *state,
1428
			    struct srp_rdma_ch *ch,
1429
			    struct scatterlist *sg)
1430
{
1431
	struct srp_target_port *target = ch->target;
1432 1433 1434 1435
	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);
1436
	unsigned int len = 0;
1437 1438
	int ret;

1439
	WARN_ON_ONCE(!dma_len);
1440

1441
	while (dma_len) {
1442
		unsigned offset = dma_addr & ~dev->mr_page_mask;
1443 1444 1445

		if (state->npages == dev->max_pages_per_mr ||
		    (state->npages > 0 && offset != 0)) {
1446
			ret = srp_map_finish_fmr(state, ch);
1447 1448 1449 1450
			if (ret)
				return ret;
		}

1451
		len = min_t(unsigned int, dma_len, dev->mr_page_size - offset);
1452

1453 1454
		if (!state->npages)
			state->base_dma_addr = dma_addr;
1455
		state->pages[state->npages++] = dma_addr & dev->mr_page_mask;
1456
		state->dma_len += len;
1457 1458 1459 1460
		dma_addr += len;
		dma_len -= len;
	}

1461
	/*
1462
	 * If the end of the MR is not on a page boundary then we need to
1463
	 * close it out and start a new one -- we can only merge at page
1464
	 * boundaries.
1465 1466
	 */
	ret = 0;
1467
	if ((dma_addr & ~dev->mr_page_mask) != 0)
1468
		ret = srp_map_finish_fmr(state, ch);
1469 1470 1471
	return ret;
}

S
Sagi Grimberg 已提交
1472 1473 1474
static int srp_map_sg_fmr(struct srp_map_state *state, struct srp_rdma_ch *ch,
			  struct srp_request *req, struct scatterlist *scat,
			  int count)
1475 1476
{
	struct scatterlist *sg;
1477
	int i, ret;
1478

S
Sagi Grimberg 已提交
1479 1480
	state->pages = req->map_page;
	state->fmr.next = req->fmr_list;
1481
	state->fmr.end = req->fmr_list + ch->target->mr_per_cmd;
S
Sagi Grimberg 已提交
1482 1483

	for_each_sg(scat, sg, count, i) {
1484
		ret = srp_map_sg_entry(state, ch, sg);
S
Sagi Grimberg 已提交
1485 1486
		if (ret)
			return ret;
1487
	}
1488

1489
	ret = srp_map_finish_fmr(state, ch);
S
Sagi Grimberg 已提交
1490 1491 1492 1493 1494 1495 1496 1497 1498 1499
	if (ret)
		return ret;

	return 0;
}

static int srp_map_sg_fr(struct srp_map_state *state, struct srp_rdma_ch *ch,
			 struct srp_request *req, struct scatterlist *scat,
			 int count)
{
1500 1501
	unsigned int sg_offset = 0;

1502
	state->fr.next = req->fr_list;
1503
	state->fr.end = req->fr_list + ch->target->mr_per_cmd;
1504
	state->sg = scat;
S
Sagi Grimberg 已提交
1505

1506 1507 1508
	if (count == 0)
		return 0;

B
Bart Van Assche 已提交
1509
	while (count) {
1510
		int i, n;
S
Sagi Grimberg 已提交
1511

1512
		n = srp_map_finish_fr(state, req, ch, count, &sg_offset);
1513 1514 1515
		if (unlikely(n < 0))
			return n;

B
Bart Van Assche 已提交
1516
		count -= n;
1517 1518 1519
		for (i = 0; i < n; i++)
			state->sg = sg_next(state->sg);
	}
S
Sagi Grimberg 已提交
1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535

	return 0;
}

static int srp_map_sg_dma(struct srp_map_state *state, struct srp_rdma_ch *ch,
			  struct srp_request *req, struct scatterlist *scat,
			  int count)
{
	struct srp_target_port *target = ch->target;
	struct srp_device *dev = target->srp_host->srp_dev;
	struct scatterlist *sg;
	int i;

	for_each_sg(scat, sg, count, i) {
		srp_map_desc(state, ib_sg_dma_address(dev->dev, sg),
			     ib_sg_dma_len(dev->dev, sg),
1536
			     target->pd->unsafe_global_rkey);
1537
	}
1538

S
Sagi Grimberg 已提交
1539
	return 0;
1540 1541
}

1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557
/*
 * Register the indirect data buffer descriptor with the HCA.
 *
 * Note: since the indirect data buffer descriptor has been allocated with
 * kmalloc() it is guaranteed that this buffer is a physically contiguous
 * memory buffer.
 */
static int srp_map_idb(struct srp_rdma_ch *ch, struct srp_request *req,
		       void **next_mr, void **end_mr, u32 idb_len,
		       __be32 *idb_rkey)
{
	struct srp_target_port *target = ch->target;
	struct srp_device *dev = target->srp_host->srp_dev;
	struct srp_map_state state;
	struct srp_direct_buf idb_desc;
	u64 idb_pages[1];
1558
	struct scatterlist idb_sg[1];
1559 1560 1561 1562 1563 1564 1565 1566 1567
	int ret;

	memset(&state, 0, sizeof(state));
	memset(&idb_desc, 0, sizeof(idb_desc));
	state.gen.next = next_mr;
	state.gen.end = end_mr;
	state.desc = &idb_desc;
	state.base_dma_addr = req->indirect_dma_addr;
	state.dma_len = idb_len;
1568 1569 1570

	if (dev->use_fast_reg) {
		state.sg = idb_sg;
1571
		sg_init_one(idb_sg, req->indirect_desc, idb_len);
1572
		idb_sg->dma_address = req->indirect_dma_addr; /* hack! */
1573 1574 1575
#ifdef CONFIG_NEED_SG_DMA_LENGTH
		idb_sg->dma_length = idb_sg->length;	      /* hack^2 */
#endif
1576
		ret = srp_map_finish_fr(&state, req, ch, 1, NULL);
1577 1578
		if (ret < 0)
			return ret;
1579
		WARN_ON_ONCE(ret < 1);
1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590
	} else if (dev->use_fmr) {
		state.pages = idb_pages;
		state.pages[0] = (req->indirect_dma_addr &
				  dev->mr_page_mask);
		state.npages = 1;
		ret = srp_map_finish_fmr(&state, ch);
		if (ret < 0)
			return ret;
	} else {
		return -EINVAL;
	}
1591 1592 1593

	*idb_rkey = idb_desc.key;

1594
	return 0;
1595 1596
}

1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620
static void srp_check_mapping(struct srp_map_state *state,
			      struct srp_rdma_ch *ch, struct srp_request *req,
			      struct scatterlist *scat, int count)
{
	struct srp_device *dev = ch->target->srp_host->srp_dev;
	struct srp_fr_desc **pfr;
	u64 desc_len = 0, mr_len = 0;
	int i;

	for (i = 0; i < state->ndesc; i++)
		desc_len += be32_to_cpu(req->indirect_desc[i].len);
	if (dev->use_fast_reg)
		for (i = 0, pfr = req->fr_list; i < state->nmdesc; i++, pfr++)
			mr_len += (*pfr)->mr->length;
	else if (dev->use_fmr)
		for (i = 0; i < state->nmdesc; i++)
			mr_len += be32_to_cpu(req->indirect_desc[i].len);
	if (desc_len != scsi_bufflen(req->scmnd) ||
	    mr_len > scsi_bufflen(req->scmnd))
		pr_err("Inconsistent: scsi len %d <> desc len %lld <> mr len %lld; ndesc %d; nmdesc = %d\n",
		       scsi_bufflen(req->scmnd), desc_len, mr_len,
		       state->ndesc, state->nmdesc);
}

1621 1622 1623 1624 1625 1626 1627 1628 1629
/**
 * srp_map_data() - map SCSI data buffer onto an SRP request
 * @scmnd: SCSI command to map
 * @ch: SRP RDMA channel
 * @req: SRP request
 *
 * Returns the length in bytes of the SRP_CMD IU or a negative value if
 * mapping failed.
 */
1630
static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_rdma_ch *ch,
1631 1632
			struct srp_request *req)
{
1633
	struct srp_target_port *target = ch->target;
1634
	struct ib_pd *pd = target->pd;
1635
	struct scatterlist *scat;
1636
	struct srp_cmd *cmd = req->cmd->buf;
1637
	int len, nents, count, ret;
1638 1639
	struct srp_device *dev;
	struct ib_device *ibdev;
1640 1641
	struct srp_map_state state;
	struct srp_indirect_buf *indirect_hdr;
1642 1643
	u32 idb_len, table_len;
	__be32 idb_rkey;
1644
	u8 fmt;
1645

1646
	if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
1647 1648 1649 1650
		return sizeof (struct srp_cmd);

	if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
	    scmnd->sc_data_direction != DMA_TO_DEVICE) {
1651 1652 1653
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled data direction %d\n",
			     scmnd->sc_data_direction);
1654 1655 1656
		return -EINVAL;
	}

1657 1658
	nents = scsi_sg_count(scmnd);
	scat  = scsi_sglist(scmnd);
1659

1660
	dev = target->srp_host->srp_dev;
1661 1662 1663
	ibdev = dev->dev;

	count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
1664 1665
	if (unlikely(count == 0))
		return -EIO;
1666 1667 1668

	fmt = SRP_DATA_DESC_DIRECT;
	len = sizeof (struct srp_cmd) +	sizeof (struct srp_direct_buf);
1669

1670
	if (count == 1 && (pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) {
1671 1672 1673 1674 1675 1676
		/*
		 * 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.
		 */
1677
		struct srp_direct_buf *buf = (void *) cmd->add_data;
1678

1679
		buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
1680
		buf->key = cpu_to_be32(pd->unsafe_global_rkey);
1681
		buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
1682

1683
		req->nmdesc = 0;
1684 1685 1686
		goto map_complete;
	}

1687 1688 1689
	/*
	 * We have more than one scatter/gather entry, so build our indirect
	 * descriptor table, trying to merge as many entries as we can.
1690 1691 1692
	 */
	indirect_hdr = (void *) cmd->add_data;

1693 1694 1695
	ib_dma_sync_single_for_cpu(ibdev, req->indirect_dma_addr,
				   target->indirect_size, DMA_TO_DEVICE);

1696
	memset(&state, 0, sizeof(state));
B
Bart Van Assche 已提交
1697
	state.desc = req->indirect_desc;
S
Sagi Grimberg 已提交
1698
	if (dev->use_fast_reg)
1699
		ret = srp_map_sg_fr(&state, ch, req, scat, count);
S
Sagi Grimberg 已提交
1700
	else if (dev->use_fmr)
1701
		ret = srp_map_sg_fmr(&state, ch, req, scat, count);
S
Sagi Grimberg 已提交
1702
	else
1703 1704 1705 1706
		ret = srp_map_sg_dma(&state, ch, req, scat, count);
	req->nmdesc = state.nmdesc;
	if (ret < 0)
		goto unmap;
1707

1708 1709 1710
	{
		DEFINE_DYNAMIC_DEBUG_METADATA(ddm,
			"Memory mapping consistency check");
1711
		if (DYNAMIC_DEBUG_BRANCH(ddm))
1712 1713
			srp_check_mapping(&state, ch, req, scat, count);
	}
1714

1715 1716 1717 1718 1719
	/* 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.
1720 1721
	 */
	if (state.ndesc == 1) {
1722 1723
		/*
		 * Memory registration collapsed the sg-list into one entry,
1724 1725 1726
		 * so use a direct descriptor.
		 */
		struct srp_direct_buf *buf = (void *) cmd->add_data;
1727

1728
		*buf = req->indirect_desc[0];
1729
		goto map_complete;
1730 1731
	}

1732 1733 1734 1735
	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");
1736 1737
		ret = -EIO;
		goto unmap;
1738 1739 1740
	}

	count = min(state.ndesc, target->cmd_sg_cnt);
1741
	table_len = state.ndesc * sizeof (struct srp_direct_buf);
1742
	idb_len = sizeof(struct srp_indirect_buf) + table_len;
1743 1744 1745

	fmt = SRP_DATA_DESC_INDIRECT;
	len = sizeof(struct srp_cmd) + sizeof (struct srp_indirect_buf);
1746
	len += count * sizeof (struct srp_direct_buf);
1747

1748 1749
	memcpy(indirect_hdr->desc_list, req->indirect_desc,
	       count * sizeof (struct srp_direct_buf));
1750

1751
	if (!(pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) {
1752 1753 1754
		ret = srp_map_idb(ch, req, state.gen.next, state.gen.end,
				  idb_len, &idb_rkey);
		if (ret < 0)
1755
			goto unmap;
1756 1757
		req->nmdesc++;
	} else {
1758
		idb_rkey = cpu_to_be32(pd->unsafe_global_rkey);
1759 1760
	}

1761
	indirect_hdr->table_desc.va = cpu_to_be64(req->indirect_dma_addr);
1762
	indirect_hdr->table_desc.key = idb_rkey;
1763 1764 1765 1766
	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)
1767
		cmd->data_out_desc_cnt = count;
1768
	else
1769 1770 1771 1772
		cmd->data_in_desc_cnt = count;

	ib_dma_sync_single_for_device(ibdev, req->indirect_dma_addr, table_len,
				      DMA_TO_DEVICE);
1773 1774

map_complete:
1775 1776 1777 1778 1779 1780
	if (scmnd->sc_data_direction == DMA_TO_DEVICE)
		cmd->buf_fmt = fmt << 4;
	else
		cmd->buf_fmt = fmt;

	return len;
1781 1782 1783

unmap:
	srp_unmap_data(scmnd, ch, req);
1784 1785
	if (ret == -ENOMEM && req->nmdesc >= target->mr_pool_size)
		ret = -E2BIG;
1786
	return ret;
1787 1788
}

1789 1790 1791
/*
 * Return an IU and possible credit to the free pool
 */
1792
static void srp_put_tx_iu(struct srp_rdma_ch *ch, struct srp_iu *iu,
1793 1794 1795 1796
			  enum srp_iu_type iu_type)
{
	unsigned long flags;

1797 1798
	spin_lock_irqsave(&ch->lock, flags);
	list_add(&iu->list, &ch->free_tx);
1799
	if (iu_type != SRP_IU_RSP)
1800 1801
		++ch->req_lim;
	spin_unlock_irqrestore(&ch->lock, flags);
1802 1803
}

1804
/*
1805
 * Must be called with ch->lock held to protect req_lim and free_tx.
1806
 * If IU is not sent, it must be returned using srp_put_tx_iu().
1807 1808 1809 1810 1811 1812 1813 1814 1815 1816
 *
 * 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.
 */
1817
static struct srp_iu *__srp_get_tx_iu(struct srp_rdma_ch *ch,
1818 1819
				      enum srp_iu_type iu_type)
{
1820
	struct srp_target_port *target = ch->target;
1821 1822 1823
	s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
	struct srp_iu *iu;

1824 1825
	lockdep_assert_held(&ch->lock);

C
Christoph Hellwig 已提交
1826
	ib_process_cq_direct(ch->send_cq, -1);
1827

1828
	if (list_empty(&ch->free_tx))
1829 1830 1831
		return NULL;

	/* Initiator responses to target requests do not consume credits */
1832
	if (iu_type != SRP_IU_RSP) {
1833
		if (ch->req_lim <= rsv) {
1834 1835 1836 1837
			++target->zero_req_lim;
			return NULL;
		}

1838
		--ch->req_lim;
1839 1840
	}

1841
	iu = list_first_entry(&ch->free_tx, struct srp_iu, list);
1842
	list_del(&iu->list);
1843 1844 1845
	return iu;
}

1846 1847 1848 1849 1850
/*
 * Note: if this function is called from inside ib_drain_sq() then it will
 * be called without ch->lock being held. If ib_drain_sq() dequeues a WQE
 * with status IB_WC_SUCCESS then that's a bug.
 */
C
Christoph Hellwig 已提交
1851 1852 1853 1854 1855 1856 1857 1858 1859 1860
static void srp_send_done(struct ib_cq *cq, struct ib_wc *wc)
{
	struct srp_iu *iu = container_of(wc->wr_cqe, struct srp_iu, cqe);
	struct srp_rdma_ch *ch = cq->cq_context;

	if (unlikely(wc->status != IB_WC_SUCCESS)) {
		srp_handle_qp_err(cq, wc, "SEND");
		return;
	}

1861 1862
	lockdep_assert_held(&ch->lock);

C
Christoph Hellwig 已提交
1863 1864 1865
	list_add(&iu->list, &ch->free_tx);
}

1866
static int srp_post_send(struct srp_rdma_ch *ch, struct srp_iu *iu, int len)
1867
{
1868
	struct srp_target_port *target = ch->target;
1869 1870 1871 1872 1873
	struct ib_sge list;
	struct ib_send_wr wr, *bad_wr;

	list.addr   = iu->dma;
	list.length = len;
1874
	list.lkey   = target->lkey;
1875

C
Christoph Hellwig 已提交
1876 1877
	iu->cqe.done = srp_send_done;

1878
	wr.next       = NULL;
C
Christoph Hellwig 已提交
1879
	wr.wr_cqe     = &iu->cqe;
1880 1881 1882 1883 1884
	wr.sg_list    = &list;
	wr.num_sge    = 1;
	wr.opcode     = IB_WR_SEND;
	wr.send_flags = IB_SEND_SIGNALED;

1885
	return ib_post_send(ch->qp, &wr, &bad_wr);
1886 1887
}

1888
static int srp_post_recv(struct srp_rdma_ch *ch, struct srp_iu *iu)
1889
{
1890
	struct srp_target_port *target = ch->target;
1891
	struct ib_recv_wr wr, *bad_wr;
1892
	struct ib_sge list;
1893 1894 1895

	list.addr   = iu->dma;
	list.length = iu->size;
1896
	list.lkey   = target->lkey;
1897

C
Christoph Hellwig 已提交
1898 1899
	iu->cqe.done = srp_recv_done;

1900
	wr.next     = NULL;
C
Christoph Hellwig 已提交
1901
	wr.wr_cqe   = &iu->cqe;
1902 1903 1904
	wr.sg_list  = &list;
	wr.num_sge  = 1;

1905
	return ib_post_recv(ch->qp, &wr, &bad_wr);
1906 1907
}

1908
static void srp_process_rsp(struct srp_rdma_ch *ch, struct srp_rsp *rsp)
1909
{
1910
	struct srp_target_port *target = ch->target;
1911 1912 1913 1914 1915
	struct srp_request *req;
	struct scsi_cmnd *scmnd;
	unsigned long flags;

	if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
1916 1917
		spin_lock_irqsave(&ch->lock, flags);
		ch->req_lim += be32_to_cpu(rsp->req_lim_delta);
1918 1919 1920 1921 1922 1923 1924 1925 1926 1927
		if (rsp->tag == ch->tsk_mgmt_tag) {
			ch->tsk_mgmt_status = -1;
			if (be32_to_cpu(rsp->resp_data_len) >= 4)
				ch->tsk_mgmt_status = rsp->data[3];
			complete(&ch->tsk_mgmt_done);
		} else {
			shost_printk(KERN_ERR, target->scsi_host,
				     "Received tsk mgmt response too late for tag %#llx\n",
				     rsp->tag);
		}
1928
		spin_unlock_irqrestore(&ch->lock, flags);
1929
	} else {
B
Bart Van Assche 已提交
1930
		scmnd = scsi_host_find_tag(target->scsi_host, rsp->tag);
1931
		if (scmnd && scmnd->host_scribble) {
B
Bart Van Assche 已提交
1932 1933
			req = (void *)scmnd->host_scribble;
			scmnd = srp_claim_req(ch, req, NULL, scmnd);
1934 1935
		} else {
			scmnd = NULL;
B
Bart Van Assche 已提交
1936
		}
B
Bart Van Assche 已提交
1937
		if (!scmnd) {
1938
			shost_printk(KERN_ERR, target->scsi_host,
B
Bart Van Assche 已提交
1939 1940
				     "Null scmnd for RSP w/tag %#016llx received on ch %td / QP %#x\n",
				     rsp->tag, ch - target->ch, ch->qp->qp_num);
B
Bart Van Assche 已提交
1941

1942 1943 1944
			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
1945 1946 1947

			return;
		}
1948 1949 1950 1951 1952 1953 1954 1955 1956
		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
1957
		if (unlikely(rsp->flags & SRP_RSP_FLAG_DIUNDER))
1958
			scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
B
Bart Van Assche 已提交
1959 1960 1961 1962 1963 1964
		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));
1965

1966
		srp_free_req(ch, req, scmnd,
B
Bart Van Assche 已提交
1967 1968
			     be32_to_cpu(rsp->req_lim_delta));

1969 1970
		scmnd->host_scribble = NULL;
		scmnd->scsi_done(scmnd);
1971 1972 1973
	}
}

1974
static int srp_response_common(struct srp_rdma_ch *ch, s32 req_delta,
1975 1976
			       void *rsp, int len)
{
1977
	struct srp_target_port *target = ch->target;
1978
	struct ib_device *dev = target->srp_host->srp_dev->dev;
1979 1980
	unsigned long flags;
	struct srp_iu *iu;
1981
	int err;
1982

1983 1984 1985 1986
	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);
1987

1988 1989 1990
	if (!iu) {
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "no IU available to send response\n");
1991
		return 1;
1992 1993 1994 1995 1996 1997
	}

	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);

1998
	err = srp_post_send(ch, iu, len);
1999
	if (err) {
2000 2001
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "unable to post response: %d\n", err);
2002
		srp_put_tx_iu(ch, iu, SRP_IU_RSP);
2003
	}
2004 2005 2006 2007

	return err;
}

2008
static void srp_process_cred_req(struct srp_rdma_ch *ch,
2009 2010 2011 2012 2013 2014 2015 2016
				 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);

2017 2018
	if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
		shost_printk(KERN_ERR, ch->target->scsi_host, PFX
2019 2020 2021
			     "problems processing SRP_CRED_REQ\n");
}

2022
static void srp_process_aer_req(struct srp_rdma_ch *ch,
2023 2024
				struct srp_aer_req *req)
{
2025
	struct srp_target_port *target = ch->target;
2026 2027 2028 2029 2030 2031 2032
	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
B
Bart Van Assche 已提交
2033
		     "ignoring AER for LUN %llu\n", scsilun_to_int(&req->lun));
2034

2035
	if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
2036 2037 2038 2039
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "problems processing SRP_AER_REQ\n");
}

C
Christoph Hellwig 已提交
2040
static void srp_recv_done(struct ib_cq *cq, struct ib_wc *wc)
2041
{
C
Christoph Hellwig 已提交
2042 2043
	struct srp_iu *iu = container_of(wc->wr_cqe, struct srp_iu, cqe);
	struct srp_rdma_ch *ch = cq->cq_context;
2044
	struct srp_target_port *target = ch->target;
2045
	struct ib_device *dev = target->srp_host->srp_dev->dev;
2046
	int res;
2047 2048
	u8 opcode;

C
Christoph Hellwig 已提交
2049 2050 2051 2052 2053
	if (unlikely(wc->status != IB_WC_SUCCESS)) {
		srp_handle_qp_err(cq, wc, "RECV");
		return;
	}

2054
	ib_dma_sync_single_for_cpu(dev, iu->dma, ch->max_ti_iu_len,
2055
				   DMA_FROM_DEVICE);
2056 2057 2058 2059

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

	if (0) {
2060 2061
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "recv completion, opcode 0x%02x\n", opcode);
B
Bart Van Assche 已提交
2062 2063
		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
			       iu->buf, wc->byte_len, true);
2064 2065 2066 2067
	}

	switch (opcode) {
	case SRP_RSP:
2068
		srp_process_rsp(ch, iu->buf);
2069 2070
		break;

2071
	case SRP_CRED_REQ:
2072
		srp_process_cred_req(ch, iu->buf);
2073 2074 2075
		break;

	case SRP_AER_REQ:
2076
		srp_process_aer_req(ch, iu->buf);
2077 2078
		break;

2079 2080
	case SRP_T_LOGOUT:
		/* XXX Handle target logout */
2081 2082
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Got target logout request\n");
2083 2084 2085
		break;

	default:
2086 2087
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled SRP opcode 0x%02x\n", opcode);
2088 2089 2090
		break;
	}

2091
	ib_dma_sync_single_for_device(dev, iu->dma, ch->max_ti_iu_len,
2092
				      DMA_FROM_DEVICE);
2093

2094
	res = srp_post_recv(ch, iu);
2095 2096 2097
	if (res != 0)
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "Recv failed with error code %d\n", res);
2098 2099
}

2100 2101
/**
 * srp_tl_err_work() - handle a transport layer error
2102
 * @work: Work structure embedded in an SRP target port.
2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115
 *
 * 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);
}

C
Christoph Hellwig 已提交
2116 2117
static void srp_handle_qp_err(struct ib_cq *cq, struct ib_wc *wc,
		const char *opname)
2118
{
C
Christoph Hellwig 已提交
2119
	struct srp_rdma_ch *ch = cq->cq_context;
2120 2121
	struct srp_target_port *target = ch->target;

2122
	if (ch->connected && !target->qp_in_error) {
C
Christoph Hellwig 已提交
2123 2124 2125 2126
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "failed %s status %s (%d) for CQE %p\n",
			     opname, ib_wc_status_msg(wc->status), wc->status,
			     wc->wr_cqe);
2127
		queue_work(system_long_wq, &target->tl_err_work);
2128
	}
2129 2130 2131
	target->qp_in_error = true;
}

2132
static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
2133
{
2134
	struct srp_target_port *target = host_to_target(shost);
2135
	struct srp_rport *rport = target->rport;
2136
	struct srp_rdma_ch *ch;
2137 2138 2139
	struct srp_request *req;
	struct srp_iu *iu;
	struct srp_cmd *cmd;
2140
	struct ib_device *dev;
2141
	unsigned long flags;
B
Bart Van Assche 已提交
2142 2143
	u32 tag;
	u16 idx;
2144
	int len, ret;
2145 2146 2147 2148 2149 2150 2151 2152 2153 2154
	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);
2155

2156 2157 2158
	scmnd->result = srp_chkready(target->rport);
	if (unlikely(scmnd->result))
		goto err;
2159

B
Bart Van Assche 已提交
2160 2161
	WARN_ON_ONCE(scmnd->request->tag < 0);
	tag = blk_mq_unique_tag(scmnd->request);
B
Bart Van Assche 已提交
2162
	ch = &target->ch[blk_mq_unique_tag_to_hwq(tag)];
B
Bart Van Assche 已提交
2163 2164 2165 2166
	idx = blk_mq_unique_tag_to_tag(tag);
	WARN_ONCE(idx >= target->req_ring_size, "%s: tag %#x: idx %d >= %d\n",
		  dev_name(&shost->shost_gendev), tag, idx,
		  target->req_ring_size);
2167 2168 2169 2170

	spin_lock_irqsave(&ch->lock, flags);
	iu = __srp_get_tx_iu(ch, SRP_IU_CMD);
	spin_unlock_irqrestore(&ch->lock, flags);
2171

B
Bart Van Assche 已提交
2172 2173 2174 2175
	if (!iu)
		goto err;

	req = &ch->req_ring[idx];
2176
	dev = target->srp_host->srp_dev->dev;
2177
	ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len,
2178
				   DMA_TO_DEVICE);
2179

2180
	scmnd->host_scribble = (void *) req;
2181 2182 2183 2184 2185

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

	cmd->opcode = SRP_CMD;
B
Bart Van Assche 已提交
2186
	int_to_scsilun(scmnd->device->lun, &cmd->lun);
B
Bart Van Assche 已提交
2187
	cmd->tag    = tag;
2188 2189 2190 2191 2192
	memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);

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

2193
	len = srp_map_data(scmnd, ch, req);
2194
	if (len < 0) {
2195
		shost_printk(KERN_ERR, target->scsi_host,
2196 2197 2198 2199
			     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
2200
		 * max_pages_per_mr sg-list elements, tell the SCSI mid-layer
2201 2202 2203 2204
		 * to reduce queue depth temporarily.
		 */
		scmnd->result = len == -ENOMEM ?
			DID_OK << 16 | QUEUE_FULL << 1 : DID_ERROR << 16;
2205
		goto err_iu;
2206 2207
	}

2208
	ib_dma_sync_single_for_device(dev, iu->dma, target->max_iu_len,
2209
				      DMA_TO_DEVICE);
2210

2211
	if (srp_post_send(ch, iu, len)) {
2212
		shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
2213 2214 2215
		goto err_unmap;
	}

2216 2217
	ret = 0;

2218 2219 2220 2221
unlock_rport:
	if (in_scsi_eh)
		mutex_unlock(&rport->mutex);

2222
	return ret;
2223 2224

err_unmap:
2225
	srp_unmap_data(scmnd, ch, req);
2226

2227
err_iu:
2228
	srp_put_tx_iu(ch, iu, SRP_IU_CMD);
2229

2230 2231 2232 2233 2234 2235
	/*
	 * Avoid that the loops that iterate over the request ring can
	 * encounter a dangling SCSI command pointer.
	 */
	req->scmnd = NULL;

2236 2237 2238 2239 2240 2241 2242
err:
	if (scmnd->result) {
		scmnd->scsi_done(scmnd);
		ret = 0;
	} else {
		ret = SCSI_MLQUEUE_HOST_BUSY;
	}
2243

2244
	goto unlock_rport;
2245 2246
}

2247 2248
/*
 * Note: the resources allocated in this function are freed in
2249
 * srp_free_ch_ib().
2250
 */
2251
static int srp_alloc_iu_bufs(struct srp_rdma_ch *ch)
2252
{
2253
	struct srp_target_port *target = ch->target;
2254 2255
	int i;

2256 2257 2258
	ch->rx_ring = kcalloc(target->queue_size, sizeof(*ch->rx_ring),
			      GFP_KERNEL);
	if (!ch->rx_ring)
2259
		goto err_no_ring;
2260 2261 2262
	ch->tx_ring = kcalloc(target->queue_size, sizeof(*ch->tx_ring),
			      GFP_KERNEL);
	if (!ch->tx_ring)
2263 2264 2265
		goto err_no_ring;

	for (i = 0; i < target->queue_size; ++i) {
2266 2267 2268 2269
		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])
2270 2271 2272
			goto err;
	}

2273
	for (i = 0; i < target->queue_size; ++i) {
2274 2275 2276 2277
		ch->tx_ring[i] = srp_alloc_iu(target->srp_host,
					      target->max_iu_len,
					      GFP_KERNEL, DMA_TO_DEVICE);
		if (!ch->tx_ring[i])
2278
			goto err;
2279

2280
		list_add(&ch->tx_ring[i]->list, &ch->free_tx);
2281 2282 2283 2284 2285
	}

	return 0;

err:
2286
	for (i = 0; i < target->queue_size; ++i) {
2287 2288
		srp_free_iu(target->srp_host, ch->rx_ring[i]);
		srp_free_iu(target->srp_host, ch->tx_ring[i]);
2289 2290
	}

2291 2292

err_no_ring:
2293 2294 2295 2296
	kfree(ch->tx_ring);
	ch->tx_ring = NULL;
	kfree(ch->rx_ring);
	ch->rx_ring = NULL;
2297

2298 2299 2300
	return -ENOMEM;
}

2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327
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;
}

2328
static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
2329
			       const struct srp_login_rsp *lrsp,
2330
			       struct srp_rdma_ch *ch)
2331
{
2332
	struct srp_target_port *target = ch->target;
2333 2334 2335 2336 2337 2338
	struct ib_qp_attr *qp_attr = NULL;
	int attr_mask = 0;
	int ret;
	int i;

	if (lrsp->opcode == SRP_LOGIN_RSP) {
2339 2340
		ch->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len);
		ch->req_lim       = be32_to_cpu(lrsp->req_lim_delta);
2341 2342 2343 2344 2345 2346

		/*
		 * Reserve credits for task management so we don't
		 * bounce requests back to the SCSI mid-layer.
		 */
		target->scsi_host->can_queue
2347
			= min(ch->req_lim - SRP_TSK_MGMT_SQ_SIZE,
2348
			      target->scsi_host->can_queue);
2349 2350 2351
		target->scsi_host->cmd_per_lun
			= min_t(int, target->scsi_host->can_queue,
				target->scsi_host->cmd_per_lun);
2352 2353 2354 2355 2356 2357 2358
	} else {
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);
		ret = -ECONNRESET;
		goto error;
	}

2359 2360
	if (!ch->rx_ring) {
		ret = srp_alloc_iu_bufs(ch);
2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374
		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;

2375
	ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2376 2377 2378
	if (ret)
		goto error_free;

2379
	for (i = 0; i < target->queue_size; i++) {
2380 2381 2382
		struct srp_iu *iu = ch->rx_ring[i];

		ret = srp_post_recv(ch, iu);
2383 2384 2385 2386 2387 2388 2389 2390 2391
		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;

2392 2393
	target->rq_tmo_jiffies = srp_compute_rq_tmo(qp_attr, attr_mask);

2394
	ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2395 2396 2397 2398 2399 2400 2401 2402 2403
	if (ret)
		goto error_free;

	ret = ib_send_cm_rtu(cm_id, NULL, 0);

error_free:
	kfree(qp_attr);

error:
2404
	ch->status = ret;
2405 2406
}

2407 2408
static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
			       struct ib_cm_event *event,
2409
			       struct srp_rdma_ch *ch)
2410
{
2411
	struct srp_target_port *target = ch->target;
2412
	struct Scsi_Host *shost = target->scsi_host;
2413 2414 2415 2416 2417 2418
	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;
2419
		sa_path_set_dlid(&ch->path, ntohs(cpi->redirect_lid));
2420
		ch->path.pkey = cpi->redirect_pkey;
2421
		cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
2422
		memcpy(ch->path.dgid.raw, cpi->redirect_gid, 16);
2423

2424
		ch->status = sa_path_get_dlid(&ch->path) ?
2425 2426 2427 2428
			SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
		break;

	case IB_CM_REJ_PORT_REDIRECT:
2429
		if (srp_target_is_topspin(target)) {
2430 2431 2432 2433 2434
			/*
			 * Topspin/Cisco SRP gateways incorrectly send
			 * reject reason code 25 when they mean 24
			 * (port redirect).
			 */
2435
			memcpy(ch->path.dgid.raw,
2436 2437
			       event->param.rej_rcvd.ari, 16);

2438 2439
			shost_printk(KERN_DEBUG, shost,
				     PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
2440 2441
				     be64_to_cpu(ch->path.dgid.global.subnet_prefix),
				     be64_to_cpu(ch->path.dgid.global.interface_id));
2442

2443
			ch->status = SRP_PORT_REDIRECT;
2444
		} else {
2445 2446
			shost_printk(KERN_WARNING, shost,
				     "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
2447
			ch->status = -ECONNRESET;
2448 2449 2450 2451
		}
		break;

	case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
2452 2453
		shost_printk(KERN_WARNING, shost,
			    "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
2454
		ch->status = -ECONNRESET;
2455 2456 2457 2458 2459 2460 2461 2462 2463
		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)
2464 2465
				shost_printk(KERN_WARNING, shost,
					     PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
2466
			else
B
Bart Van Assche 已提交
2467 2468
				shost_printk(KERN_WARNING, shost, PFX
					     "SRP LOGIN from %pI6 to %pI6 REJECTED, reason 0x%08x\n",
2469 2470
					     target->sgid.raw,
					     target->orig_dgid.raw, reason);
2471
		} else
2472 2473 2474
			shost_printk(KERN_WARNING, shost,
				     "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
				     " opcode 0x%02x\n", opcode);
2475
		ch->status = -ECONNRESET;
2476 2477
		break;

D
David Dillow 已提交
2478 2479
	case IB_CM_REJ_STALE_CONN:
		shost_printk(KERN_WARNING, shost, "  REJ reason: stale connection\n");
2480
		ch->status = SRP_STALE_CONN;
D
David Dillow 已提交
2481 2482
		break;

2483
	default:
2484 2485
		shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
			     event->param.rej_rcvd.reason);
2486
		ch->status = -ECONNRESET;
2487 2488 2489 2490 2491
	}
}

static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
{
2492 2493
	struct srp_rdma_ch *ch = cm_id->context;
	struct srp_target_port *target = ch->target;
2494 2495 2496 2497
	int comp = 0;

	switch (event->event) {
	case IB_CM_REQ_ERROR:
2498 2499
		shost_printk(KERN_DEBUG, target->scsi_host,
			     PFX "Sending CM REQ failed\n");
2500
		comp = 1;
2501
		ch->status = -ECONNRESET;
2502 2503 2504 2505
		break;

	case IB_CM_REP_RECEIVED:
		comp = 1;
2506
		srp_cm_rep_handler(cm_id, event->private_data, ch);
2507 2508 2509
		break;

	case IB_CM_REJ_RECEIVED:
2510
		shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
2511 2512
		comp = 1;

2513
		srp_cm_rej_handler(cm_id, event, ch);
2514 2515
		break;

2516
	case IB_CM_DREQ_RECEIVED:
2517 2518
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "DREQ received - connection closed\n");
2519
		ch->connected = false;
2520
		if (ib_send_cm_drep(cm_id, NULL, 0))
2521 2522
			shost_printk(KERN_ERR, target->scsi_host,
				     PFX "Sending CM DREP failed\n");
2523
		queue_work(system_long_wq, &target->tl_err_work);
2524 2525 2526
		break;

	case IB_CM_TIMEWAIT_EXIT:
2527 2528
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "connection closed\n");
2529
		comp = 1;
2530

2531
		ch->status = 0;
2532 2533
		break;

2534 2535 2536 2537 2538
	case IB_CM_MRA_RECEIVED:
	case IB_CM_DREQ_ERROR:
	case IB_CM_DREP_RECEIVED:
		break;

2539
	default:
2540 2541
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled CM event %d\n", event->event);
2542 2543 2544 2545
		break;
	}

	if (comp)
2546
		complete(&ch->done);
2547 2548 2549 2550

	return 0;
}

2551 2552 2553 2554 2555 2556 2557 2558
/**
 * srp_change_queue_depth - setting device queue depth
 * @sdev: scsi device struct
 * @qdepth: requested queue depth
 *
 * Returns queue depth.
 */
static int
2559
srp_change_queue_depth(struct scsi_device *sdev, int qdepth)
2560
{
2561
	if (!sdev->tagged_supported)
2562
		qdepth = 1;
2563
	return scsi_change_queue_depth(sdev, qdepth);
2564 2565
}

B
Bart Van Assche 已提交
2566
static int srp_send_tsk_mgmt(struct srp_rdma_ch *ch, u64 req_tag, u64 lun,
2567
			     u8 func, u8 *status)
2568
{
2569
	struct srp_target_port *target = ch->target;
2570
	struct srp_rport *rport = target->rport;
2571
	struct ib_device *dev = target->srp_host->srp_dev->dev;
2572 2573
	struct srp_iu *iu;
	struct srp_tsk_mgmt *tsk_mgmt;
2574
	int res;
2575

2576
	if (!ch->connected || target->qp_in_error)
2577 2578
		return -1;

2579
	/*
2580
	 * Lock the rport mutex to avoid that srp_create_ch_ib() is
2581 2582 2583
	 * invoked while a task management function is being sent.
	 */
	mutex_lock(&rport->mutex);
2584 2585 2586
	spin_lock_irq(&ch->lock);
	iu = __srp_get_tx_iu(ch, SRP_IU_TSK_MGMT);
	spin_unlock_irq(&ch->lock);
2587

2588 2589 2590
	if (!iu) {
		mutex_unlock(&rport->mutex);

2591
		return -1;
2592
	}
2593

2594 2595
	ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
				   DMA_TO_DEVICE);
2596 2597 2598 2599
	tsk_mgmt = iu->buf;
	memset(tsk_mgmt, 0, sizeof *tsk_mgmt);

	tsk_mgmt->opcode 	= SRP_TSK_MGMT;
B
Bart Van Assche 已提交
2600
	int_to_scsilun(lun, &tsk_mgmt->lun);
2601
	tsk_mgmt->tsk_mgmt_func = func;
2602
	tsk_mgmt->task_tag	= req_tag;
2603

2604 2605 2606 2607 2608 2609 2610
	spin_lock_irq(&ch->lock);
	ch->tsk_mgmt_tag = (ch->tsk_mgmt_tag + 1) | SRP_TAG_TSK_MGMT;
	tsk_mgmt->tag = ch->tsk_mgmt_tag;
	spin_unlock_irq(&ch->lock);

	init_completion(&ch->tsk_mgmt_done);

2611 2612
	ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
				      DMA_TO_DEVICE);
2613 2614
	if (srp_post_send(ch, iu, sizeof(*tsk_mgmt))) {
		srp_put_tx_iu(ch, iu, SRP_IU_TSK_MGMT);
2615 2616
		mutex_unlock(&rport->mutex);

2617 2618
		return -1;
	}
2619 2620 2621 2622
	res = wait_for_completion_timeout(&ch->tsk_mgmt_done,
					msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS));
	if (res > 0 && status)
		*status = ch->tsk_mgmt_status;
2623
	mutex_unlock(&rport->mutex);
2624

2625
	WARN_ON_ONCE(res < 0);
2626

2627
	return res > 0 ? 0 : -1;
2628 2629
}

2630 2631
static int srp_abort(struct scsi_cmnd *scmnd)
{
2632
	struct srp_target_port *target = host_to_target(scmnd->device->host);
2633
	struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
B
Bart Van Assche 已提交
2634
	u32 tag;
B
Bart Van Assche 已提交
2635
	u16 ch_idx;
2636
	struct srp_rdma_ch *ch;
2637
	int ret;
2638

2639
	shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
2640

B
Bart Van Assche 已提交
2641
	if (!req)
2642
		return SUCCESS;
B
Bart Van Assche 已提交
2643
	tag = blk_mq_unique_tag(scmnd->request);
B
Bart Van Assche 已提交
2644 2645 2646 2647 2648 2649 2650 2651
	ch_idx = blk_mq_unique_tag_to_hwq(tag);
	if (WARN_ON_ONCE(ch_idx >= target->ch_count))
		return SUCCESS;
	ch = &target->ch[ch_idx];
	if (!srp_claim_req(ch, req, NULL, scmnd))
		return SUCCESS;
	shost_printk(KERN_ERR, target->scsi_host,
		     "Sending SRP abort for tag %#x\n", tag);
B
Bart Van Assche 已提交
2652
	if (srp_send_tsk_mgmt(ch, tag, scmnd->device->lun,
2653
			      SRP_TSK_ABORT_TASK, NULL) == 0)
2654
		ret = SUCCESS;
2655
	else if (target->rport->state == SRP_RPORT_LOST)
2656
		ret = FAST_IO_FAIL;
2657 2658
	else
		ret = FAILED;
2659
	srp_free_req(ch, req, scmnd, 0);
B
Bart Van Assche 已提交
2660
	scmnd->result = DID_ABORT << 16;
2661
	scmnd->scsi_done(scmnd);
2662

2663
	return ret;
2664 2665 2666 2667
}

static int srp_reset_device(struct scsi_cmnd *scmnd)
{
2668
	struct srp_target_port *target = host_to_target(scmnd->device->host);
B
Bart Van Assche 已提交
2669
	struct srp_rdma_ch *ch;
2670
	int i;
2671
	u8 status;
2672

2673
	shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
2674

B
Bart Van Assche 已提交
2675
	ch = &target->ch[0];
2676
	if (srp_send_tsk_mgmt(ch, SRP_TAG_NO_REQ, scmnd->device->lun,
2677
			      SRP_TSK_LUN_RESET, &status))
2678
		return FAILED;
2679
	if (status)
2680 2681
		return FAILED;

B
Bart Van Assche 已提交
2682 2683 2684 2685
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		for (i = 0; i < target->req_ring_size; ++i) {
			struct srp_request *req = &ch->req_ring[i];
2686

B
Bart Van Assche 已提交
2687 2688
			srp_finish_req(ch, req, scmnd->device, DID_RESET << 16);
		}
2689
	}
2690 2691

	return SUCCESS;
2692 2693 2694 2695 2696 2697
}

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

2698
	shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
2699

2700
	return srp_reconnect_rport(target->rport) == 0 ? SUCCESS : FAILED;
2701 2702
}

2703 2704 2705 2706 2707 2708
static int srp_slave_alloc(struct scsi_device *sdev)
{
	struct Scsi_Host *shost = sdev->host;
	struct srp_target_port *target = host_to_target(shost);
	struct srp_device *srp_dev = target->srp_host->srp_dev;

2709
	if (true)
2710 2711 2712 2713 2714 2715
		blk_queue_virt_boundary(sdev->request_queue,
					~srp_dev->mr_page_mask);

	return 0;
}

2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730
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;
}

2731 2732
static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
			   char *buf)
2733
{
2734
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2735

2736
	return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->id_ext));
2737 2738
}

2739 2740
static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
			     char *buf)
2741
{
2742
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2743

2744
	return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->ioc_guid));
2745 2746
}

2747 2748
static ssize_t show_service_id(struct device *dev,
			       struct device_attribute *attr, char *buf)
2749
{
2750
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2751

2752
	return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->service_id));
2753 2754
}

2755 2756
static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
			 char *buf)
2757
{
2758
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2759

2760
	return sprintf(buf, "0x%04x\n", be16_to_cpu(target->pkey));
2761 2762
}

B
Bart Van Assche 已提交
2763 2764 2765 2766 2767
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));

2768
	return sprintf(buf, "%pI6\n", target->sgid.raw);
B
Bart Van Assche 已提交
2769 2770
}

2771 2772
static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
			 char *buf)
2773
{
2774
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
B
Bart Van Assche 已提交
2775
	struct srp_rdma_ch *ch = &target->ch[0];
2776

2777
	return sprintf(buf, "%pI6\n", ch->path.dgid.raw);
2778 2779
}

2780 2781
static ssize_t show_orig_dgid(struct device *dev,
			      struct device_attribute *attr, char *buf)
2782
{
2783
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2784

2785
	return sprintf(buf, "%pI6\n", target->orig_dgid.raw);
2786 2787
}

2788 2789 2790 2791
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));
B
Bart Van Assche 已提交
2792 2793
	struct srp_rdma_ch *ch;
	int i, req_lim = INT_MAX;
2794

B
Bart Van Assche 已提交
2795 2796 2797 2798 2799
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		req_lim = min(req_lim, ch->req_lim);
	}
	return sprintf(buf, "%d\n", req_lim);
2800 2801
}

2802 2803
static ssize_t show_zero_req_lim(struct device *dev,
				 struct device_attribute *attr, char *buf)
2804
{
2805
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2806 2807 2808 2809

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

2810 2811
static ssize_t show_local_ib_port(struct device *dev,
				  struct device_attribute *attr, char *buf)
2812
{
2813
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2814 2815 2816 2817

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

2818 2819
static ssize_t show_local_ib_device(struct device *dev,
				    struct device_attribute *attr, char *buf)
2820
{
2821
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2822

2823
	return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
2824 2825
}

B
Bart Van Assche 已提交
2826 2827 2828 2829 2830 2831 2832 2833
static ssize_t show_ch_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->ch_count);
}

2834 2835 2836 2837 2838 2839 2840 2841
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);
}

2842 2843 2844 2845 2846 2847 2848 2849
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);
}

2850 2851 2852 2853 2854 2855 2856 2857
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);
}

2858 2859 2860 2861 2862 2863 2864 2865
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");
}

2866 2867 2868 2869
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
2870
static DEVICE_ATTR(sgid,	    S_IRUGO, show_sgid,		   NULL);
2871 2872
static DEVICE_ATTR(dgid,	    S_IRUGO, show_dgid,		   NULL);
static DEVICE_ATTR(orig_dgid,	    S_IRUGO, show_orig_dgid,	   NULL);
2873
static DEVICE_ATTR(req_lim,         S_IRUGO, show_req_lim,         NULL);
2874 2875 2876
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);
B
Bart Van Assche 已提交
2877
static DEVICE_ATTR(ch_count,        S_IRUGO, show_ch_count,        NULL);
2878
static DEVICE_ATTR(comp_vector,     S_IRUGO, show_comp_vector,     NULL);
2879
static DEVICE_ATTR(tl_retry_count,  S_IRUGO, show_tl_retry_count,  NULL);
2880
static DEVICE_ATTR(cmd_sg_entries,  S_IRUGO, show_cmd_sg_entries,  NULL);
2881
static DEVICE_ATTR(allow_ext_sg,    S_IRUGO, show_allow_ext_sg,    NULL);
2882 2883 2884 2885 2886 2887

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
2888
	&dev_attr_sgid,
2889 2890
	&dev_attr_dgid,
	&dev_attr_orig_dgid,
2891
	&dev_attr_req_lim,
2892 2893 2894
	&dev_attr_zero_req_lim,
	&dev_attr_local_ib_port,
	&dev_attr_local_ib_device,
B
Bart Van Assche 已提交
2895
	&dev_attr_ch_count,
2896
	&dev_attr_comp_vector,
2897
	&dev_attr_tl_retry_count,
2898
	&dev_attr_cmd_sg_entries,
2899
	&dev_attr_allow_ext_sg,
2900 2901 2902
	NULL
};

2903 2904
static struct scsi_host_template srp_template = {
	.module				= THIS_MODULE,
R
Roland Dreier 已提交
2905 2906
	.name				= "InfiniBand SRP initiator",
	.proc_name			= DRV_NAME,
2907
	.slave_alloc			= srp_slave_alloc,
2908
	.slave_configure		= srp_slave_configure,
2909 2910
	.info				= srp_target_info,
	.queuecommand			= srp_queuecommand,
2911
	.change_queue_depth             = srp_change_queue_depth,
2912
	.eh_timed_out			= srp_timed_out,
2913 2914 2915
	.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
2916
	.skip_settle_delay		= true,
2917
	.sg_tablesize			= SRP_DEF_SG_TABLESIZE,
2918
	.can_queue			= SRP_DEFAULT_CMD_SQ_SIZE,
2919
	.this_id			= -1,
2920
	.cmd_per_lun			= SRP_DEFAULT_CMD_SQ_SIZE,
2921
	.use_clustering			= ENABLE_CLUSTERING,
B
Bart Van Assche 已提交
2922
	.shost_attrs			= srp_host_attrs,
2923
	.track_queue_depth		= 1,
2924 2925
};

2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936
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;
}

2937 2938 2939 2940 2941 2942 2943
/*
 * Return values:
 * < 0 upon failure. Caller is responsible for SRP target port cleanup.
 * 0 and target->state == SRP_TARGET_REMOVED if asynchronous target port
 *    removal has been scheduled.
 * 0 and target->state != SRP_TARGET_REMOVED upon success.
 */
2944 2945
static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
{
2946 2947 2948
	struct srp_rport_identifiers ids;
	struct srp_rport *rport;

2949
	target->state = SRP_TARGET_SCANNING;
2950
	sprintf(target->target_name, "SRP.T10:%016llX",
2951
		be64_to_cpu(target->id_ext));
2952

2953
	if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dev.parent))
2954 2955
		return -ENODEV;

2956 2957
	memcpy(ids.port_id, &target->id_ext, 8);
	memcpy(ids.port_id + 8, &target->ioc_guid, 8);
2958
	ids.roles = SRP_RPORT_ROLE_TARGET;
2959 2960 2961 2962 2963 2964
	rport = srp_rport_add(target->scsi_host, &ids);
	if (IS_ERR(rport)) {
		scsi_remove_host(target->scsi_host);
		return PTR_ERR(rport);
	}

2965
	rport->lld_data = target;
2966
	target->rport = rport;
2967

2968
	spin_lock(&host->target_lock);
2969
	list_add_tail(&target->list, &host->target_list);
2970
	spin_unlock(&host->target_lock);
2971 2972

	scsi_scan_target(&target->scsi_host->shost_gendev,
2973
			 0, target->scsi_id, SCAN_WILD_CARD, SCSI_SCAN_INITIAL);
2974

2975 2976
	if (srp_connected_ch(target) < target->ch_count ||
	    target->qp_in_error) {
2977 2978 2979 2980 2981 2982
		shost_printk(KERN_INFO, target->scsi_host,
			     PFX "SCSI scan failed - removing SCSI host\n");
		srp_queue_remove_work(target);
		goto out;
	}

2983
	pr_debug("%s: SCSI scan succeeded - detected %d LUNs\n",
2984 2985 2986 2987 2988 2989 2990 2991 2992
		 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:
2993 2994 2995
	return 0;
}

2996
static void srp_release_dev(struct device *dev)
2997 2998
{
	struct srp_host *host =
2999
		container_of(dev, struct srp_host, dev);
3000 3001 3002 3003 3004 3005

	complete(&host->released);
}

static struct class srp_class = {
	.name    = "infiniband_srp",
3006
	.dev_release = srp_release_dev
3007 3008
};

3009 3010
/**
 * srp_conn_unique() - check whether the connection to a target is unique
3011 3012
 * @host:   SRP host.
 * @target: SRP target port.
3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040
 */
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;
}

3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056
/*
 * 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,
3057
	SRP_OPT_MAX_CMD_PER_LUN	= 1 << 6,
3058
	SRP_OPT_IO_CLASS	= 1 << 7,
3059
	SRP_OPT_INITIATOR_EXT	= 1 << 8,
3060
	SRP_OPT_CMD_SG_ENTRIES	= 1 << 9,
3061 3062
	SRP_OPT_ALLOW_EXT_SG	= 1 << 10,
	SRP_OPT_SG_TABLESIZE	= 1 << 11,
3063
	SRP_OPT_COMP_VECTOR	= 1 << 12,
3064
	SRP_OPT_TL_RETRY_COUNT	= 1 << 13,
3065
	SRP_OPT_QUEUE_SIZE	= 1 << 14,
3066 3067 3068 3069 3070 3071 3072
	SRP_OPT_ALL		= (SRP_OPT_ID_EXT	|
				   SRP_OPT_IOC_GUID	|
				   SRP_OPT_DGID		|
				   SRP_OPT_PKEY		|
				   SRP_OPT_SERVICE_ID),
};

3073
static const match_table_t srp_opt_tokens = {
3074 3075 3076 3077 3078 3079 3080
	{ 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" 	},
3081
	{ SRP_OPT_IO_CLASS,		"io_class=%x"		},
3082
	{ SRP_OPT_INITIATOR_EXT,	"initiator_ext=%s"	},
3083
	{ SRP_OPT_CMD_SG_ENTRIES,	"cmd_sg_entries=%u"	},
3084 3085
	{ SRP_OPT_ALLOW_EXT_SG,		"allow_ext_sg=%u"	},
	{ SRP_OPT_SG_TABLESIZE,		"sg_tablesize=%u"	},
3086
	{ SRP_OPT_COMP_VECTOR,		"comp_vector=%u"	},
3087
	{ SRP_OPT_TL_RETRY_COUNT,	"tl_retry_count=%u"	},
3088
	{ SRP_OPT_QUEUE_SIZE,		"queue_size=%d"		},
3089
	{ SRP_OPT_ERR,			NULL 			}
3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107
};

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;
3108
	while ((p = strsep(&sep_opt, ",\n")) != NULL) {
3109 3110 3111 3112 3113 3114 3115 3116 3117
		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);
3118 3119 3120 3121
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3122 3123 3124 3125 3126 3127
			target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

		case SRP_OPT_IOC_GUID:
			p = match_strdup(args);
3128 3129 3130 3131
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3132 3133 3134 3135 3136 3137
			target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

		case SRP_OPT_DGID:
			p = match_strdup(args);
3138 3139 3140 3141
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3142
			if (strlen(p) != 32) {
3143
				pr_warn("bad dest GID parameter '%s'\n", p);
3144
				kfree(p);
3145 3146 3147 3148
				goto out;
			}

			for (i = 0; i < 16; ++i) {
3149 3150 3151 3152 3153 3154 3155
				strlcpy(dgid, p + i * 2, sizeof(dgid));
				if (sscanf(dgid, "%hhx",
					   &target->orig_dgid.raw[i]) < 1) {
					ret = -EINVAL;
					kfree(p);
					goto out;
				}
3156
			}
3157
			kfree(p);
3158 3159 3160 3161
			break;

		case SRP_OPT_PKEY:
			if (match_hex(args, &token)) {
3162
				pr_warn("bad P_Key parameter '%s'\n", p);
3163 3164
				goto out;
			}
3165
			target->pkey = cpu_to_be16(token);
3166 3167 3168 3169
			break;

		case SRP_OPT_SERVICE_ID:
			p = match_strdup(args);
3170 3171 3172 3173
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3174 3175 3176 3177 3178 3179
			target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

		case SRP_OPT_MAX_SECT:
			if (match_int(args, &token)) {
3180
				pr_warn("bad max sect parameter '%s'\n", p);
3181 3182 3183 3184 3185
				goto out;
			}
			target->scsi_host->max_sectors = token;
			break;

3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197
		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;

3198
		case SRP_OPT_MAX_CMD_PER_LUN:
3199
			if (match_int(args, &token) || token < 1) {
3200 3201
				pr_warn("bad max cmd_per_lun parameter '%s'\n",
					p);
3202 3203
				goto out;
			}
3204
			target->scsi_host->cmd_per_lun = token;
3205 3206
			break;

3207 3208
		case SRP_OPT_IO_CLASS:
			if (match_hex(args, &token)) {
3209
				pr_warn("bad IO class parameter '%s'\n", p);
3210 3211 3212 3213
				goto out;
			}
			if (token != SRP_REV10_IB_IO_CLASS &&
			    token != SRP_REV16A_IB_IO_CLASS) {
3214 3215 3216
				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);
3217 3218 3219 3220 3221
				goto out;
			}
			target->io_class = token;
			break;

3222 3223
		case SRP_OPT_INITIATOR_EXT:
			p = match_strdup(args);
3224 3225 3226 3227
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3228 3229 3230 3231
			target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

3232 3233
		case SRP_OPT_CMD_SG_ENTRIES:
			if (match_int(args, &token) || token < 1 || token > 255) {
3234 3235
				pr_warn("bad max cmd_sg_entries parameter '%s'\n",
					p);
3236 3237 3238 3239 3240
				goto out;
			}
			target->cmd_sg_cnt = token;
			break;

3241 3242
		case SRP_OPT_ALLOW_EXT_SG:
			if (match_int(args, &token)) {
3243
				pr_warn("bad allow_ext_sg parameter '%s'\n", p);
3244 3245 3246 3247 3248 3249 3250
				goto out;
			}
			target->allow_ext_sg = !!token;
			break;

		case SRP_OPT_SG_TABLESIZE:
			if (match_int(args, &token) || token < 1 ||
3251
					token > SG_MAX_SEGMENTS) {
3252 3253
				pr_warn("bad max sg_tablesize parameter '%s'\n",
					p);
3254 3255 3256 3257 3258
				goto out;
			}
			target->sg_tablesize = token;
			break;

3259 3260 3261 3262 3263 3264 3265 3266
		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;

3267 3268 3269 3270 3271 3272 3273 3274 3275
		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;

3276
		default:
3277 3278
			pr_warn("unknown parameter or missing value '%s' in target creation request\n",
				p);
3279 3280 3281 3282 3283 3284 3285 3286 3287 3288
			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))
3289 3290
				pr_warn("target creation request is missing parameter '%s'\n",
					srp_opt_tokens[i].pattern);
3291

3292 3293 3294 3295 3296 3297
	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);

3298 3299 3300 3301 3302
out:
	kfree(options);
	return ret;
}

3303 3304
static ssize_t srp_create_target(struct device *dev,
				 struct device_attribute *attr,
3305 3306 3307
				 const char *buf, size_t count)
{
	struct srp_host *host =
3308
		container_of(dev, struct srp_host, dev);
3309 3310
	struct Scsi_Host *target_host;
	struct srp_target_port *target;
3311
	struct srp_rdma_ch *ch;
3312 3313
	struct srp_device *srp_dev = host->srp_dev;
	struct ib_device *ibdev = srp_dev->dev;
B
Bart Van Assche 已提交
3314
	int ret, node_idx, node, cpu, i;
3315
	unsigned int max_sectors_per_mr, mr_per_cmd = 0;
B
Bart Van Assche 已提交
3316
	bool multich = false;
3317 3318 3319 3320 3321 3322

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

3323
	target_host->transportt  = ib_srp_transport_template;
3324 3325
	target_host->max_channel = 0;
	target_host->max_id      = 1;
B
Bart Van Assche 已提交
3326
	target_host->max_lun     = -1LL;
A
Arne Redlich 已提交
3327
	target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
R
Roland Dreier 已提交
3328

3329 3330
	target = host_to_target(target_host);

3331 3332 3333
	target->io_class	= SRP_REV16A_IB_IO_CLASS;
	target->scsi_host	= target_host;
	target->srp_host	= host;
3334
	target->pd		= host->srp_dev->pd;
J
Jason Gunthorpe 已提交
3335
	target->lkey		= host->srp_dev->pd->local_dma_lkey;
3336
	target->cmd_sg_cnt	= cmd_sg_entries;
3337 3338
	target->sg_tablesize	= indirect_sg_entries ? : cmd_sg_entries;
	target->allow_ext_sg	= allow_ext_sg;
3339
	target->tl_retry_count	= 7;
3340
	target->queue_size	= SRP_DEFAULT_QUEUE_SIZE;
3341

3342 3343 3344 3345 3346 3347
	/*
	 * Avoid that the SCSI host can be removed by srp_remove_target()
	 * before this function returns.
	 */
	scsi_host_get(target->scsi_host);

3348 3349 3350
	ret = mutex_lock_interruptible(&host->add_target_mutex);
	if (ret < 0)
		goto put;
3351

3352 3353
	ret = srp_parse_options(buf, target);
	if (ret)
3354
		goto out;
3355

3356 3357
	target->req_ring_size = target->queue_size - SRP_TSK_MGMT_SQ_SIZE;

3358 3359 3360 3361 3362 3363 3364
	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;
3365
		goto out;
3366 3367
	}

3368
	if (!srp_dev->has_fmr && !srp_dev->has_fr && !target->allow_ext_sg &&
3369
	    target->cmd_sg_cnt < target->sg_tablesize) {
3370
		pr_warn("No MR pool and no external indirect descriptors, limiting sg_tablesize to cmd_sg_cnt\n");
3371 3372 3373
		target->sg_tablesize = target->cmd_sg_cnt;
	}

3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397
	if (srp_dev->use_fast_reg || srp_dev->use_fmr) {
		/*
		 * FR and FMR can only map one HCA page per entry. If the
		 * start address is not aligned on a HCA page boundary two
		 * entries will be used for the head and the tail although
		 * these two entries combined contain at most one HCA page of
		 * data. Hence the "+ 1" in the calculation below.
		 *
		 * The indirect data buffer descriptor is contiguous so the
		 * memory for that buffer will only be registered if
		 * register_always is true. Hence add one to mr_per_cmd if
		 * register_always has been set.
		 */
		max_sectors_per_mr = srp_dev->max_pages_per_mr <<
				  (ilog2(srp_dev->mr_page_size) - 9);
		mr_per_cmd = register_always +
			(target->scsi_host->max_sectors + 1 +
			 max_sectors_per_mr - 1) / max_sectors_per_mr;
		pr_debug("max_sectors = %u; max_pages_per_mr = %u; mr_page_size = %u; max_sectors_per_mr = %u; mr_per_cmd = %u\n",
			 target->scsi_host->max_sectors,
			 srp_dev->max_pages_per_mr, srp_dev->mr_page_size,
			 max_sectors_per_mr, mr_per_cmd);
	}

3398
	target_host->sg_tablesize = target->sg_tablesize;
3399 3400
	target->mr_pool_size = target->scsi_host->can_queue * mr_per_cmd;
	target->mr_per_cmd = mr_per_cmd;
3401 3402
	target->indirect_size = target->sg_tablesize *
				sizeof (struct srp_direct_buf);
3403 3404 3405 3406
	target->max_iu_len = sizeof (struct srp_cmd) +
			     sizeof (struct srp_indirect_buf) +
			     target->cmd_sg_cnt * sizeof (struct srp_direct_buf);

3407
	INIT_WORK(&target->tl_err_work, srp_tl_err_work);
3408
	INIT_WORK(&target->remove_work, srp_remove_work);
3409
	spin_lock_init(&target->lock);
3410
	ret = ib_query_gid(ibdev, host->port, 0, &target->sgid, NULL);
3411
	if (ret)
3412
		goto out;
3413

B
Bart Van Assche 已提交
3414 3415 3416 3417 3418 3419 3420 3421 3422
	ret = -ENOMEM;
	target->ch_count = max_t(unsigned, num_online_nodes(),
				 min(ch_count ? :
				     min(4 * num_online_nodes(),
					 ibdev->num_comp_vectors),
				     num_online_cpus()));
	target->ch = kcalloc(target->ch_count, sizeof(*target->ch),
			     GFP_KERNEL);
	if (!target->ch)
3423
		goto out;
3424

B
Bart Van Assche 已提交
3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452
	node_idx = 0;
	for_each_online_node(node) {
		const int ch_start = (node_idx * target->ch_count /
				      num_online_nodes());
		const int ch_end = ((node_idx + 1) * target->ch_count /
				    num_online_nodes());
		const int cv_start = (node_idx * ibdev->num_comp_vectors /
				      num_online_nodes() + target->comp_vector)
				     % ibdev->num_comp_vectors;
		const int cv_end = ((node_idx + 1) * ibdev->num_comp_vectors /
				    num_online_nodes() + target->comp_vector)
				   % ibdev->num_comp_vectors;
		int cpu_idx = 0;

		for_each_online_cpu(cpu) {
			if (cpu_to_node(cpu) != node)
				continue;
			if (ch_start + cpu_idx >= ch_end)
				continue;
			ch = &target->ch[ch_start + cpu_idx];
			ch->target = target;
			ch->comp_vector = cv_start == cv_end ? cv_start :
				cv_start + cpu_idx % (cv_end - cv_start);
			spin_lock_init(&ch->lock);
			INIT_LIST_HEAD(&ch->free_tx);
			ret = srp_new_cm_id(ch);
			if (ret)
				goto err_disconnect;
3453

B
Bart Van Assche 已提交
3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464
			ret = srp_create_ch_ib(ch);
			if (ret)
				goto err_disconnect;

			ret = srp_alloc_req_data(ch);
			if (ret)
				goto err_disconnect;

			ret = srp_connect_ch(ch, multich);
			if (ret) {
				shost_printk(KERN_ERR, target->scsi_host,
3465
					     PFX "Connection %d/%d to %pI6 failed\n",
B
Bart Van Assche 已提交
3466
					     ch_start + cpu_idx,
3467 3468
					     target->ch_count,
					     ch->target->orig_dgid.raw);
B
Bart Van Assche 已提交
3469
				if (node_idx == 0 && cpu_idx == 0) {
B
Bart Van Assche 已提交
3470
					goto free_ch;
B
Bart Van Assche 已提交
3471 3472 3473 3474
				} else {
					srp_free_ch_ib(target, ch);
					srp_free_req_data(target, ch);
					target->ch_count = ch - target->ch;
3475
					goto connected;
B
Bart Van Assche 已提交
3476 3477 3478 3479 3480 3481 3482
				}
			}

			multich = true;
			cpu_idx++;
		}
		node_idx++;
3483 3484
	}

3485
connected:
B
Bart Van Assche 已提交
3486 3487
	target->scsi_host->nr_hw_queues = target->ch_count;

3488 3489 3490 3491
	ret = srp_add_target(host, target);
	if (ret)
		goto err_disconnect;

3492 3493 3494 3495 3496
	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),
3497
			     be16_to_cpu(target->pkey),
3498
			     be64_to_cpu(target->service_id),
3499
			     target->sgid.raw, target->orig_dgid.raw);
3500
	}
B
Bart Van Assche 已提交
3501

3502 3503 3504 3505
	ret = count;

out:
	mutex_unlock(&host->add_target_mutex);
3506

3507
put:
3508
	scsi_host_put(target->scsi_host);
3509 3510
	if (ret < 0)
		scsi_host_put(target->scsi_host);
3511

3512
	return ret;
3513 3514 3515 3516

err_disconnect:
	srp_disconnect_target(target);

B
Bart Van Assche 已提交
3517
free_ch:
B
Bart Van Assche 已提交
3518 3519 3520 3521 3522
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		srp_free_ch_ib(target, ch);
		srp_free_req_data(target, ch);
	}
3523

B
Bart Van Assche 已提交
3524
	kfree(target->ch);
3525
	goto out;
3526 3527
}

3528
static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
3529

3530 3531
static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
			  char *buf)
3532
{
3533
	struct srp_host *host = container_of(dev, struct srp_host, dev);
3534

3535
	return sprintf(buf, "%s\n", host->srp_dev->dev->name);
3536 3537
}

3538
static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
3539

3540 3541
static ssize_t show_port(struct device *dev, struct device_attribute *attr,
			 char *buf)
3542
{
3543
	struct srp_host *host = container_of(dev, struct srp_host, dev);
3544 3545 3546 3547

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

3548
static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
3549

3550
static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
3551 3552 3553 3554 3555 3556 3557 3558
{
	struct srp_host *host;

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

	INIT_LIST_HEAD(&host->target_list);
3559
	spin_lock_init(&host->target_lock);
3560
	init_completion(&host->released);
3561
	mutex_init(&host->add_target_mutex);
3562
	host->srp_dev = device;
3563 3564
	host->port = port;

3565
	host->dev.class = &srp_class;
3566
	host->dev.parent = device->dev->dev.parent;
3567
	dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
3568

3569
	if (device_register(&host->dev))
3570
		goto free_host;
3571
	if (device_create_file(&host->dev, &dev_attr_add_target))
3572
		goto err_class;
3573
	if (device_create_file(&host->dev, &dev_attr_ibdev))
3574
		goto err_class;
3575
	if (device_create_file(&host->dev, &dev_attr_port))
3576 3577 3578 3579 3580
		goto err_class;

	return host;

err_class:
3581
	device_unregister(&host->dev);
3582

3583
free_host:
3584 3585 3586 3587 3588 3589 3590
	kfree(host);

	return NULL;
}

static void srp_add_one(struct ib_device *device)
{
3591
	struct srp_device *srp_dev;
3592
	struct ib_device_attr *attr = &device->attrs;
3593
	struct srp_host *host;
3594
	int mr_page_shift, p;
3595
	u64 max_pages_per_mr;
3596
	unsigned int flags = 0;
3597

3598
	srp_dev = kzalloc(sizeof(*srp_dev), GFP_KERNEL);
3599
	if (!srp_dev)
3600
		return;
3601 3602 3603

	/*
	 * Use the smallest page size supported by the HCA, down to a
3604 3605
	 * minimum of 4096 bytes. We're unlikely to build large sglists
	 * out of smaller entries.
3606
	 */
3607
	mr_page_shift		= max(12, ffs(attr->page_size_cap) - 1);
3608 3609
	srp_dev->mr_page_size	= 1 << mr_page_shift;
	srp_dev->mr_page_mask	= ~((u64) srp_dev->mr_page_size - 1);
3610
	max_pages_per_mr	= attr->max_mr_size;
3611
	do_div(max_pages_per_mr, srp_dev->mr_page_size);
3612
	pr_debug("%s: %llu / %u = %llu <> %u\n", __func__,
3613
		 attr->max_mr_size, srp_dev->mr_page_size,
3614
		 max_pages_per_mr, SRP_MAX_PAGES_PER_MR);
3615 3616
	srp_dev->max_pages_per_mr = min_t(u64, SRP_MAX_PAGES_PER_MR,
					  max_pages_per_mr);
3617 3618 3619

	srp_dev->has_fmr = (device->alloc_fmr && device->dealloc_fmr &&
			    device->map_phys_fmr && device->unmap_fmr);
3620
	srp_dev->has_fr = (attr->device_cap_flags &
3621
			   IB_DEVICE_MEM_MGT_EXTENSIONS);
3622
	if (!never_register && !srp_dev->has_fmr && !srp_dev->has_fr) {
3623
		dev_warn(&device->dev, "neither FMR nor FR is supported\n");
3624
	} else if (!never_register &&
3625
		   attr->max_mr_size >= 2 * srp_dev->mr_page_size) {
3626 3627 3628 3629
		srp_dev->use_fast_reg = (srp_dev->has_fr &&
					 (!srp_dev->has_fmr || prefer_fr));
		srp_dev->use_fmr = !srp_dev->use_fast_reg && srp_dev->has_fmr;
	}
3630

3631 3632 3633 3634
	if (never_register || !register_always ||
	    (!srp_dev->has_fmr && !srp_dev->has_fr))
		flags |= IB_PD_UNSAFE_GLOBAL_RKEY;

3635 3636 3637
	if (srp_dev->use_fast_reg) {
		srp_dev->max_pages_per_mr =
			min_t(u32, srp_dev->max_pages_per_mr,
3638
			      attr->max_fast_reg_page_list_len);
3639
	}
3640 3641
	srp_dev->mr_max_size	= srp_dev->mr_page_size *
				   srp_dev->max_pages_per_mr;
3642
	pr_debug("%s: mr_page_shift = %d, device->max_mr_size = %#llx, device->max_fast_reg_page_list_len = %u, max_pages_per_mr = %d, mr_max_size = %#x\n",
3643 3644
		 device->name, mr_page_shift, attr->max_mr_size,
		 attr->max_fast_reg_page_list_len,
3645
		 srp_dev->max_pages_per_mr, srp_dev->mr_max_size);
3646 3647 3648 3649

	INIT_LIST_HEAD(&srp_dev->dev_list);

	srp_dev->dev = device;
3650
	srp_dev->pd  = ib_alloc_pd(device, flags);
3651 3652 3653 3654
	if (IS_ERR(srp_dev->pd))
		goto free_dev;


3655
	for (p = rdma_start_port(device); p <= rdma_end_port(device); ++p) {
3656
		host = srp_add_port(srp_dev, p);
3657
		if (host)
3658
			list_add_tail(&host->list, &srp_dev->dev_list);
3659 3660
	}

3661
	ib_set_client_data(device, &srp_client, srp_dev);
3662
	return;
3663 3664 3665

free_dev:
	kfree(srp_dev);
3666 3667
}

3668
static void srp_remove_one(struct ib_device *device, void *client_data)
3669
{
3670
	struct srp_device *srp_dev;
3671
	struct srp_host *host, *tmp_host;
3672
	struct srp_target_port *target;
3673

3674
	srp_dev = client_data;
3675 3676
	if (!srp_dev)
		return;
3677

3678
	list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
3679
		device_unregister(&host->dev);
3680 3681 3682 3683 3684 3685 3686
		/*
		 * Wait for the sysfs entry to go away, so that no new
		 * target ports can be created.
		 */
		wait_for_completion(&host->released);

		/*
3687
		 * Remove all target ports.
3688
		 */
3689
		spin_lock(&host->target_lock);
3690 3691
		list_for_each_entry(target, &host->target_list, list)
			srp_queue_remove_work(target);
3692
		spin_unlock(&host->target_lock);
3693 3694

		/*
3695
		 * Wait for tl_err and target port removal tasks.
3696
		 */
3697
		flush_workqueue(system_long_wq);
3698
		flush_workqueue(srp_remove_wq);
3699 3700 3701 3702

		kfree(host);
	}

3703 3704 3705
	ib_dealloc_pd(srp_dev->pd);

	kfree(srp_dev);
3706 3707
}

3708
static struct srp_function_template ib_srp_transport_functions = {
3709 3710
	.has_rport_state	 = true,
	.reset_timer_if_blocked	 = true,
3711
	.reconnect_delay	 = &srp_reconnect_delay,
3712 3713 3714
	.fast_io_fail_tmo	 = &srp_fast_io_fail_tmo,
	.dev_loss_tmo		 = &srp_dev_loss_tmo,
	.reconnect		 = srp_rport_reconnect,
3715
	.rport_delete		 = srp_rport_delete,
3716
	.terminate_rport_io	 = srp_terminate_io,
3717 3718
};

3719 3720 3721 3722
static int __init srp_init_module(void)
{
	int ret;

3723
	if (srp_sg_tablesize) {
3724
		pr_warn("srp_sg_tablesize is deprecated, please use cmd_sg_entries\n");
3725 3726 3727 3728 3729 3730 3731 3732
		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) {
3733
		pr_warn("Clamping cmd_sg_entries to 255\n");
3734
		cmd_sg_entries = 255;
3735 3736
	}

3737 3738 3739
	if (!indirect_sg_entries)
		indirect_sg_entries = cmd_sg_entries;
	else if (indirect_sg_entries < cmd_sg_entries) {
3740 3741
		pr_warn("Bumping up indirect_sg_entries to match cmd_sg_entries (%u)\n",
			cmd_sg_entries);
3742 3743 3744
		indirect_sg_entries = cmd_sg_entries;
	}

3745 3746 3747 3748 3749 3750
	if (indirect_sg_entries > SG_MAX_SEGMENTS) {
		pr_warn("Clamping indirect_sg_entries to %u\n",
			SG_MAX_SEGMENTS);
		indirect_sg_entries = SG_MAX_SEGMENTS;
	}

3751
	srp_remove_wq = create_workqueue("srp_remove");
3752 3753
	if (!srp_remove_wq) {
		ret = -ENOMEM;
3754 3755 3756 3757
		goto out;
	}

	ret = -ENOMEM;
3758 3759 3760
	ib_srp_transport_template =
		srp_attach_transport(&ib_srp_transport_functions);
	if (!ib_srp_transport_template)
3761
		goto destroy_wq;
3762

3763 3764
	ret = class_register(&srp_class);
	if (ret) {
3765
		pr_err("couldn't register class infiniband_srp\n");
3766
		goto release_tr;
3767 3768
	}

3769 3770
	ib_sa_register_client(&srp_sa_client);

3771 3772
	ret = ib_register_client(&srp_client);
	if (ret) {
3773
		pr_err("couldn't register IB client\n");
3774
		goto unreg_sa;
3775 3776
	}

3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789
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;
3790 3791 3792 3793 3794
}

static void __exit srp_cleanup_module(void)
{
	ib_unregister_client(&srp_client);
3795
	ib_sa_unregister_client(&srp_sa_client);
3796
	class_unregister(&srp_class);
3797
	srp_release_transport(ib_srp_transport_template);
3798
	destroy_workqueue(srp_remove_wq);
3799 3800 3801 3802
}

module_init(srp_init_module);
module_exit(srp_cleanup_module);