ib_srp.c 98.3 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 <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_VERSION(DRV_VERSION);
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;
	ch->path.sgid = target->sgid;
	ch->path.dgid = target->orig_dgid;
	ch->path.pkey = target->pkey;
	ch->path.service_id = target->service_id;
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	return 0;
}

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

	memset(&fmr_param, 0, sizeof(fmr_param));
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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;
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	enum ib_mr_type mr_type;
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	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);

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	if (device->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG)
		mr_type = IB_MR_TYPE_SG_GAPS;
	else
		mr_type = IB_MR_TYPE_MEM_REG;

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	for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) {
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		mr = ib_alloc_mr(pd, mr_type, 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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 * @qp: RDMA queue pair.
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 *
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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
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 * being destroyed.
 */
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static void srp_destroy_qp(struct ib_qp *qp)
474
{
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	ib_drain_rq(qp);
	ib_destroy_qp(qp);
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}

479
static int srp_create_ch_ib(struct srp_rdma_ch *ch)
480
{
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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->qp);
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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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	srp_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
588
 * invoked. Hence the ch->[rt]x_ring checks.
589
 */
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static void srp_free_ch_ib(struct srp_target_port *target,
			   struct srp_rdma_ch *ch)
592
{
593
	struct srp_device *dev = target->srp_host->srp_dev;
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	int i;

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	if (!ch->target)
		return;

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

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Bart Van Assche 已提交
604 605 606 607
	/* If srp_new_cm_id() succeeded but srp_create_ch_ib() not, return. */
	if (!ch->qp)
		return;

608
	if (dev->use_fast_reg) {
609 610
		if (ch->fr_pool)
			srp_destroy_fr_pool(ch->fr_pool);
611
	} else if (dev->use_fmr) {
612 613
		if (ch->fmr_pool)
			ib_destroy_fmr_pool(ch->fmr_pool);
614
	}
C
Christoph Hellwig 已提交
615

616
	srp_destroy_qp(ch->qp);
C
Christoph Hellwig 已提交
617 618
	ib_free_cq(ch->send_cq);
	ib_free_cq(ch->recv_cq);
619

B
Bart Van Assche 已提交
620 621 622 623 624 625 626 627
	/*
	 * 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;

628 629
	ch->qp = NULL;
	ch->send_cq = ch->recv_cq = NULL;
630

631
	if (ch->rx_ring) {
632
		for (i = 0; i < target->queue_size; ++i)
633 634 635
			srp_free_iu(target->srp_host, ch->rx_ring[i]);
		kfree(ch->rx_ring);
		ch->rx_ring = NULL;
636
	}
637
	if (ch->tx_ring) {
638
		for (i = 0; i < target->queue_size; ++i)
639 640 641
			srp_free_iu(target->srp_host, ch->tx_ring[i]);
		kfree(ch->tx_ring);
		ch->tx_ring = NULL;
642
	}
643 644 645 646
}

static void srp_path_rec_completion(int status,
				    struct ib_sa_path_rec *pathrec,
647
				    void *ch_ptr)
648
{
649 650
	struct srp_rdma_ch *ch = ch_ptr;
	struct srp_target_port *target = ch->target;
651

652
	ch->status = status;
653
	if (status)
654 655
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "Got failed path rec status %d\n", status);
656
	else
657 658
		ch->path = *pathrec;
	complete(&ch->done);
659 660
}

661
static int srp_lookup_path(struct srp_rdma_ch *ch)
662
{
663
	struct srp_target_port *target = ch->target;
664 665
	int ret;

666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686
	ch->path.numb_path = 1;

	init_completion(&ch->done);

	ch->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
					       target->srp_host->srp_dev->dev,
					       target->srp_host->port,
					       &ch->path,
					       IB_SA_PATH_REC_SERVICE_ID |
					       IB_SA_PATH_REC_DGID	 |
					       IB_SA_PATH_REC_SGID	 |
					       IB_SA_PATH_REC_NUMB_PATH	 |
					       IB_SA_PATH_REC_PKEY,
					       SRP_PATH_REC_TIMEOUT_MS,
					       GFP_KERNEL,
					       srp_path_rec_completion,
					       ch, &ch->path_query);
	if (ch->path_query_id < 0)
		return ch->path_query_id;

	ret = wait_for_completion_interruptible(&ch->done);
687 688
	if (ret < 0)
		return ret;
689

690
	if (ch->status < 0)
691 692
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Path record query failed\n");
693

694
	return ch->status;
695 696
}

B
Bart Van Assche 已提交
697
static int srp_send_req(struct srp_rdma_ch *ch, bool multich)
698
{
699
	struct srp_target_port *target = ch->target;
700 701 702 703 704 705 706 707 708 709
	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;

710
	req->param.primary_path		      = &ch->path;
711 712
	req->param.alternate_path 	      = NULL;
	req->param.service_id 		      = target->service_id;
713 714
	req->param.qp_num		      = ch->qp->qp_num;
	req->param.qp_type		      = ch->qp->qp_type;
715 716 717 718 719 720 721 722 723 724 725 726 727 728
	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;
729
	req->param.retry_count                = target->tl_retry_count;
730 731 732 733 734
	req->param.rnr_retry_count 	      = 7;
	req->param.max_cm_retries 	      = 15;

	req->priv.opcode     	= SRP_LOGIN_REQ;
	req->priv.tag        	= 0;
735
	req->priv.req_it_iu_len = cpu_to_be32(target->max_iu_len);
736 737
	req->priv.req_buf_fmt 	= cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
					      SRP_BUF_FORMAT_INDIRECT);
B
Bart Van Assche 已提交
738 739
	req->priv.req_flags	= (multich ? SRP_MULTICHAN_MULTI :
				   SRP_MULTICHAN_SINGLE);
740
	/*
R
Roland Dreier 已提交
741
	 * In the published SRP specification (draft rev. 16a), the
742 743 744 745 746 747 748 749 750
	 * 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,
751
		       &target->sgid.global.interface_id, 8);
752
		memcpy(req->priv.initiator_port_id + 8,
753
		       &target->initiator_ext, 8);
754 755 756 757
		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,
758 759
		       &target->initiator_ext, 8);
		memcpy(req->priv.initiator_port_id + 8,
760
		       &target->sgid.global.interface_id, 8);
761 762 763 764
		memcpy(req->priv.target_port_id,     &target->id_ext, 8);
		memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
	}

765 766
	/*
	 * Topspin/Cisco SRP targets will reject our login unless we
767 768
	 * zero out the first 8 bytes of our initiator port ID and set
	 * the second 8 bytes to the local node GUID.
769
	 */
770
	if (srp_target_is_topspin(target)) {
771 772 773
		shost_printk(KERN_DEBUG, target->scsi_host,
			     PFX "Topspin/Cisco initiator port ID workaround "
			     "activated for target GUID %016llx\n",
774
			     be64_to_cpu(target->ioc_guid));
775
		memset(req->priv.initiator_port_id, 0, 8);
776
		memcpy(req->priv.initiator_port_id + 8,
777
		       &target->srp_host->srp_dev->dev->node_guid, 8);
778 779
	}

780
	status = ib_send_cm_req(ch->cm_id, &req->param);
781 782 783 784 785 786

	kfree(req);

	return status;
}

787 788 789 790 791 792 793 794 795 796 797 798
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)
799
		queue_work(srp_remove_wq, &target->remove_work);
800 801 802 803

	return changed;
}

804 805
static void srp_disconnect_target(struct srp_target_port *target)
{
B
Bart Van Assche 已提交
806 807
	struct srp_rdma_ch *ch;
	int i;
808

809
	/* XXX should send SRP_I_LOGOUT request */
810

811 812 813 814 815 816
	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");
817
		}
818
	}
819 820
}

821 822
static void srp_free_req_data(struct srp_target_port *target,
			      struct srp_rdma_ch *ch)
823
{
824 825
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
826 827 828
	struct srp_request *req;
	int i;

829
	if (!ch->req_ring)
830 831 832
		return;

	for (i = 0; i < target->req_ring_size; ++i) {
833
		req = &ch->req_ring[i];
834
		if (dev->use_fast_reg) {
835
			kfree(req->fr_list);
836
		} else {
837
			kfree(req->fmr_list);
838 839
			kfree(req->map_page);
		}
840 841 842 843 844 845
		if (req->indirect_dma_addr) {
			ib_dma_unmap_single(ibdev, req->indirect_dma_addr,
					    target->indirect_size,
					    DMA_TO_DEVICE);
		}
		kfree(req->indirect_desc);
846
	}
847

848 849
	kfree(ch->req_ring);
	ch->req_ring = NULL;
850 851
}

852
static int srp_alloc_req_data(struct srp_rdma_ch *ch)
853
{
854
	struct srp_target_port *target = ch->target;
855 856 857
	struct srp_device *srp_dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = srp_dev->dev;
	struct srp_request *req;
858
	void *mr_list;
859 860 861
	dma_addr_t dma_addr;
	int i, ret = -ENOMEM;

862 863 864
	ch->req_ring = kcalloc(target->req_ring_size, sizeof(*ch->req_ring),
			       GFP_KERNEL);
	if (!ch->req_ring)
865 866 867
		goto out;

	for (i = 0; i < target->req_ring_size; ++i) {
868
		req = &ch->req_ring[i];
869
		mr_list = kmalloc(target->mr_per_cmd * sizeof(void *),
870 871 872
				  GFP_KERNEL);
		if (!mr_list)
			goto out;
873
		if (srp_dev->use_fast_reg) {
874
			req->fr_list = mr_list;
875
		} else {
876
			req->fmr_list = mr_list;
877 878 879 880 881
			req->map_page = kmalloc(srp_dev->max_pages_per_mr *
						sizeof(void *), GFP_KERNEL);
			if (!req->map_page)
				goto out;
		}
882
		req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
883
		if (!req->indirect_desc)
884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899
			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;
}

900 901 902 903 904 905 906 907 908 909 910 911 912 913 914
/**
 * 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);
}

915 916
static void srp_remove_target(struct srp_target_port *target)
{
B
Bart Van Assche 已提交
917 918
	struct srp_rdma_ch *ch;
	int i;
919

920 921
	WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);

922
	srp_del_scsi_host_attr(target->scsi_host);
923
	srp_rport_get(target->rport);
924 925
	srp_remove_host(target->scsi_host);
	scsi_remove_host(target->scsi_host);
926
	srp_stop_rport_timers(target->rport);
927
	srp_disconnect_target(target);
B
Bart Van Assche 已提交
928 929 930 931
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		srp_free_ch_ib(target, ch);
	}
932
	cancel_work_sync(&target->tl_err_work);
933
	srp_rport_put(target->rport);
B
Bart Van Assche 已提交
934 935 936 937 938 939
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		srp_free_req_data(target, ch);
	}
	kfree(target->ch);
	target->ch = NULL;
940 941 942 943 944

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

945 946 947
	scsi_host_put(target->scsi_host);
}

D
David Howells 已提交
948
static void srp_remove_work(struct work_struct *work)
949
{
D
David Howells 已提交
950
	struct srp_target_port *target =
951
		container_of(work, struct srp_target_port, remove_work);
952

953
	WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
954

955
	srp_remove_target(target);
956 957
}

958 959 960 961 962 963 964
static void srp_rport_delete(struct srp_rport *rport)
{
	struct srp_target_port *target = rport->lld_data;

	srp_queue_remove_work(target);
}

965 966 967 968 969 970 971 972 973 974 975 976 977 978
/**
 * 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
979
static int srp_connect_ch(struct srp_rdma_ch *ch, bool multich)
980
{
981
	struct srp_target_port *target = ch->target;
982 983
	int ret;

984
	WARN_ON_ONCE(!multich && srp_connected_ch(target) > 0);
985

986
	ret = srp_lookup_path(ch);
987
	if (ret)
B
Bart Van Assche 已提交
988
		goto out;
989 990

	while (1) {
991
		init_completion(&ch->done);
B
Bart Van Assche 已提交
992
		ret = srp_send_req(ch, multich);
993
		if (ret)
B
Bart Van Assche 已提交
994
			goto out;
995
		ret = wait_for_completion_interruptible(&ch->done);
996
		if (ret < 0)
B
Bart Van Assche 已提交
997
			goto out;
998 999 1000 1001 1002 1003 1004

		/*
		 * 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
1005 1006
		ret = ch->status;
		switch (ret) {
1007
		case 0:
1008
			ch->connected = true;
B
Bart Van Assche 已提交
1009
			goto out;
1010 1011

		case SRP_PORT_REDIRECT:
1012
			ret = srp_lookup_path(ch);
1013
			if (ret)
B
Bart Van Assche 已提交
1014
				goto out;
1015 1016 1017 1018 1019
			break;

		case SRP_DLID_REDIRECT:
			break;

D
David Dillow 已提交
1020 1021
		case SRP_STALE_CONN:
			shost_printk(KERN_ERR, target->scsi_host, PFX
1022
				     "giving up on stale connection\n");
B
Bart Van Assche 已提交
1023 1024
			ret = -ECONNRESET;
			goto out;
D
David Dillow 已提交
1025

1026
		default:
B
Bart Van Assche 已提交
1027
			goto out;
1028 1029
		}
	}
B
Bart Van Assche 已提交
1030 1031 1032

out:
	return ret <= 0 ? ret : -ENODEV;
1033 1034
}

C
Christoph Hellwig 已提交
1035 1036 1037 1038 1039 1040 1041
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)
1042 1043 1044 1045 1046 1047 1048 1049 1050 1051
{
	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
1052 1053
	wr.wr_cqe = &req->reg_cqe;
	req->reg_cqe.done = srp_inv_rkey_err_done;
1054
	return ib_post_send(ch->qp, &wr, &bad_wr);
1055 1056
}

1057
static void srp_unmap_data(struct scsi_cmnd *scmnd,
1058
			   struct srp_rdma_ch *ch,
1059 1060
			   struct srp_request *req)
{
1061
	struct srp_target_port *target = ch->target;
1062 1063 1064
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
	int i, res;
1065

1066
	if (!scsi_sglist(scmnd) ||
1067 1068 1069 1070
	    (scmnd->sc_data_direction != DMA_TO_DEVICE &&
	     scmnd->sc_data_direction != DMA_FROM_DEVICE))
		return;

1071 1072 1073 1074
	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
1075
			res = srp_inv_rkey(req, ch, (*pfr)->mr->rkey);
1076 1077 1078 1079 1080 1081 1082 1083 1084
			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)
1085
			srp_fr_pool_put(ch->fr_pool, req->fr_list,
1086
					req->nmdesc);
1087
	} else if (dev->use_fmr) {
1088 1089 1090 1091 1092
		struct ib_pool_fmr **pfmr;

		for (i = req->nmdesc, pfmr = req->fmr_list; i > 0; i--, pfmr++)
			ib_fmr_pool_unmap(*pfmr);
	}
1093

1094 1095
	ib_dma_unmap_sg(ibdev, scsi_sglist(scmnd), scsi_sg_count(scmnd),
			scmnd->sc_data_direction);
1096 1097
}

B
Bart Van Assche 已提交
1098 1099
/**
 * srp_claim_req - Take ownership of the scmnd associated with a request.
1100
 * @ch: SRP RDMA channel.
B
Bart Van Assche 已提交
1101
 * @req: SRP request.
1102
 * @sdev: If not NULL, only take ownership for this SCSI device.
B
Bart Van Assche 已提交
1103 1104 1105 1106 1107 1108
 * @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.
 */
1109
static struct scsi_cmnd *srp_claim_req(struct srp_rdma_ch *ch,
B
Bart Van Assche 已提交
1110
				       struct srp_request *req,
1111
				       struct scsi_device *sdev,
B
Bart Van Assche 已提交
1112 1113 1114 1115
				       struct scsi_cmnd *scmnd)
{
	unsigned long flags;

1116
	spin_lock_irqsave(&ch->lock, flags);
1117 1118 1119
	if (req->scmnd &&
	    (!sdev || req->scmnd->device == sdev) &&
	    (!scmnd || req->scmnd == scmnd)) {
B
Bart Van Assche 已提交
1120 1121 1122 1123 1124
		scmnd = req->scmnd;
		req->scmnd = NULL;
	} else {
		scmnd = NULL;
	}
1125
	spin_unlock_irqrestore(&ch->lock, flags);
B
Bart Van Assche 已提交
1126 1127 1128 1129 1130

	return scmnd;
}

/**
B
Bart Van Assche 已提交
1131
 * srp_free_req() - Unmap data and adjust ch->req_lim.
1132
 * @ch:     SRP RDMA channel.
1133 1134 1135
 * @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
1136
 */
1137 1138
static void srp_free_req(struct srp_rdma_ch *ch, struct srp_request *req,
			 struct scsi_cmnd *scmnd, s32 req_lim_delta)
1139
{
1140 1141
	unsigned long flags;

1142
	srp_unmap_data(scmnd, ch, req);
B
Bart Van Assche 已提交
1143

1144 1145 1146
	spin_lock_irqsave(&ch->lock, flags);
	ch->req_lim += req_lim_delta;
	spin_unlock_irqrestore(&ch->lock, flags);
1147 1148
}

1149 1150
static void srp_finish_req(struct srp_rdma_ch *ch, struct srp_request *req,
			   struct scsi_device *sdev, int result)
1151
{
1152
	struct scsi_cmnd *scmnd = srp_claim_req(ch, req, sdev, NULL);
B
Bart Van Assche 已提交
1153 1154

	if (scmnd) {
1155
		srp_free_req(ch, req, scmnd, 0);
1156
		scmnd->result = result;
B
Bart Van Assche 已提交
1157 1158
		scmnd->scsi_done(scmnd);
	}
1159 1160
}

1161
static void srp_terminate_io(struct srp_rport *rport)
1162
{
1163
	struct srp_target_port *target = rport->lld_data;
B
Bart Van Assche 已提交
1164
	struct srp_rdma_ch *ch;
1165 1166
	struct Scsi_Host *shost = target->scsi_host;
	struct scsi_device *sdev;
B
Bart Van Assche 已提交
1167
	int i, j;
1168

1169 1170 1171 1172 1173 1174 1175
	/*
	 * 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
1176 1177
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
1178

B
Bart Van Assche 已提交
1179 1180 1181 1182 1183 1184
		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);
		}
1185 1186
	}
}
1187

1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199
/*
 * 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
1200 1201 1202
	struct srp_rdma_ch *ch;
	int i, j, ret = 0;
	bool multich = false;
1203

1204
	srp_disconnect_target(target);
1205 1206 1207 1208

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

1209
	/*
1210 1211 1212
	 * 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.
1213
	 */
B
Bart Van Assche 已提交
1214 1215 1216
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		ret += srp_new_cm_id(ch);
1217
	}
B
Bart Van Assche 已提交
1218 1219 1220 1221
	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];
1222

B
Bart Van Assche 已提交
1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233
			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);
1234

B
Bart Van Assche 已提交
1235 1236 1237 1238
		INIT_LIST_HEAD(&ch->free_tx);
		for (j = 0; j < target->queue_size; ++j)
			list_add(&ch->tx_ring[j]->list, &ch->free_tx);
	}
1239 1240 1241

	target->qp_in_error = false;

B
Bart Van Assche 已提交
1242 1243
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
1244
		if (ret)
B
Bart Van Assche 已提交
1245 1246 1247 1248
			break;
		ret = srp_connect_ch(ch, multich);
		multich = true;
	}
1249

1250 1251 1252
	if (ret == 0)
		shost_printk(KERN_INFO, target->scsi_host,
			     PFX "reconnect succeeded\n");
1253 1254 1255 1256

	return ret;
}

1257 1258
static void srp_map_desc(struct srp_map_state *state, dma_addr_t dma_addr,
			 unsigned int dma_len, u32 rkey)
1259
{
1260
	struct srp_direct_buf *desc = state->desc;
1261

1262 1263
	WARN_ON_ONCE(!dma_len);

1264 1265 1266
	desc->va = cpu_to_be64(dma_addr);
	desc->key = cpu_to_be32(rkey);
	desc->len = cpu_to_be32(dma_len);
1267

1268 1269 1270 1271
	state->total_len += dma_len;
	state->desc++;
	state->ndesc++;
}
1272

1273
static int srp_map_finish_fmr(struct srp_map_state *state,
1274
			      struct srp_rdma_ch *ch)
1275
{
1276 1277
	struct srp_target_port *target = ch->target;
	struct srp_device *dev = target->srp_host->srp_dev;
1278
	struct ib_pd *pd = target->pd;
1279 1280
	struct ib_pool_fmr *fmr;
	u64 io_addr = 0;
1281

1282 1283 1284 1285
	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);
1286
		return -ENOMEM;
1287
	}
1288

S
Sagi Grimberg 已提交
1289 1290 1291 1292 1293
	WARN_ON_ONCE(!dev->use_fmr);

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

1294
	if (state->npages == 1 && (pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) {
S
Sagi Grimberg 已提交
1295
		srp_map_desc(state, state->base_dma_addr, state->dma_len,
1296
			     pd->unsafe_global_rkey);
S
Sagi Grimberg 已提交
1297 1298 1299
		goto reset_state;
	}

1300
	fmr = ib_fmr_pool_map_phys(ch->fmr_pool, state->pages,
1301 1302 1303
				   state->npages, io_addr);
	if (IS_ERR(fmr))
		return PTR_ERR(fmr);
1304

1305
	*state->fmr.next++ = fmr;
1306
	state->nmdesc++;
1307

1308 1309
	srp_map_desc(state, state->base_dma_addr & ~dev->mr_page_mask,
		     state->dma_len, fmr->fmr->rkey);
1310

S
Sagi Grimberg 已提交
1311 1312 1313 1314
reset_state:
	state->npages = 0;
	state->dma_len = 0;

1315 1316 1317
	return 0;
}

C
Christoph Hellwig 已提交
1318 1319 1320 1321 1322
static void srp_reg_mr_err_done(struct ib_cq *cq, struct ib_wc *wc)
{
	srp_handle_qp_err(cq, wc, "FAST REG");
}

1323 1324 1325 1326 1327 1328
/*
 * 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.
 */
1329
static int srp_map_finish_fr(struct srp_map_state *state,
C
Christoph Hellwig 已提交
1330
			     struct srp_request *req,
1331 1332
			     struct srp_rdma_ch *ch, int sg_nents,
			     unsigned int *sg_offset_p)
1333
{
1334
	struct srp_target_port *target = ch->target;
1335
	struct srp_device *dev = target->srp_host->srp_dev;
1336
	struct ib_pd *pd = target->pd;
1337
	struct ib_send_wr *bad_wr;
1338
	struct ib_reg_wr wr;
1339 1340
	struct srp_fr_desc *desc;
	u32 rkey;
1341
	int n, err;
1342

1343 1344 1345 1346
	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);
1347
		return -ENOMEM;
1348
	}
1349

S
Sagi Grimberg 已提交
1350 1351
	WARN_ON_ONCE(!dev->use_fast_reg);

1352
	if (sg_nents == 1 && (pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) {
1353 1354 1355 1356
		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,
1357
			     pd->unsafe_global_rkey);
1358 1359
		if (sg_offset_p)
			*sg_offset_p = 0;
1360
		return 1;
S
Sagi Grimberg 已提交
1361 1362
	}

1363
	desc = srp_fr_pool_get(ch->fr_pool);
1364 1365 1366 1367 1368 1369
	if (!desc)
		return -ENOMEM;

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

1370 1371
	n = ib_map_mr_sg(desc->mr, state->sg, sg_nents, sg_offset_p,
			 dev->mr_page_size);
1372 1373
	if (unlikely(n < 0)) {
		srp_fr_pool_put(ch->fr_pool, &desc, 1);
1374
		pr_debug("%s: ib_map_mr_sg(%d, %d) returned %d.\n",
1375
			 dev_name(&req->scmnd->device->sdev_gendev), sg_nents,
1376
			 sg_offset_p ? *sg_offset_p : -1, n);
1377
		return n;
1378
	}
1379

1380
	WARN_ON_ONCE(desc->mr->length == 0);
1381

C
Christoph Hellwig 已提交
1382 1383
	req->reg_cqe.done = srp_reg_mr_err_done;

1384 1385
	wr.wr.next = NULL;
	wr.wr.opcode = IB_WR_REG_MR;
C
Christoph Hellwig 已提交
1386
	wr.wr.wr_cqe = &req->reg_cqe;
1387 1388 1389 1390 1391 1392 1393
	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);
1394

1395
	*state->fr.next++ = desc;
1396 1397
	state->nmdesc++;

1398 1399
	srp_map_desc(state, desc->mr->iova,
		     desc->mr->length, desc->mr->rkey);
1400

S
Sagi Grimberg 已提交
1401
	err = ib_post_send(ch->qp, &wr.wr, &bad_wr);
1402 1403
	if (unlikely(err)) {
		WARN_ON_ONCE(err == -ENOMEM);
S
Sagi Grimberg 已提交
1404
		return err;
1405
	}
S
Sagi Grimberg 已提交
1406

1407
	return n;
1408 1409
}

1410
static int srp_map_sg_entry(struct srp_map_state *state,
1411
			    struct srp_rdma_ch *ch,
1412
			    struct scatterlist *sg)
1413
{
1414
	struct srp_target_port *target = ch->target;
1415 1416 1417 1418
	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);
1419
	unsigned int len = 0;
1420 1421
	int ret;

1422
	WARN_ON_ONCE(!dma_len);
1423

1424
	while (dma_len) {
1425
		unsigned offset = dma_addr & ~dev->mr_page_mask;
1426 1427 1428

		if (state->npages == dev->max_pages_per_mr ||
		    (state->npages > 0 && offset != 0)) {
1429
			ret = srp_map_finish_fmr(state, ch);
1430 1431 1432 1433
			if (ret)
				return ret;
		}

1434
		len = min_t(unsigned int, dma_len, dev->mr_page_size - offset);
1435

1436 1437
		if (!state->npages)
			state->base_dma_addr = dma_addr;
1438
		state->pages[state->npages++] = dma_addr & dev->mr_page_mask;
1439
		state->dma_len += len;
1440 1441 1442 1443
		dma_addr += len;
		dma_len -= len;
	}

1444
	/*
1445
	 * If the end of the MR is not on a page boundary then we need to
1446
	 * close it out and start a new one -- we can only merge at page
1447
	 * boundaries.
1448 1449
	 */
	ret = 0;
1450
	if ((dma_addr & ~dev->mr_page_mask) != 0)
1451
		ret = srp_map_finish_fmr(state, ch);
1452 1453 1454
	return ret;
}

S
Sagi Grimberg 已提交
1455 1456 1457
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)
1458 1459
{
	struct scatterlist *sg;
1460
	int i, ret;
1461

S
Sagi Grimberg 已提交
1462 1463
	state->pages = req->map_page;
	state->fmr.next = req->fmr_list;
1464
	state->fmr.end = req->fmr_list + ch->target->mr_per_cmd;
S
Sagi Grimberg 已提交
1465 1466

	for_each_sg(scat, sg, count, i) {
1467
		ret = srp_map_sg_entry(state, ch, sg);
S
Sagi Grimberg 已提交
1468 1469
		if (ret)
			return ret;
1470
	}
1471

1472
	ret = srp_map_finish_fmr(state, ch);
S
Sagi Grimberg 已提交
1473 1474 1475 1476 1477 1478 1479 1480 1481 1482
	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)
{
1483 1484
	unsigned int sg_offset = 0;

1485
	state->fr.next = req->fr_list;
1486
	state->fr.end = req->fr_list + ch->target->mr_per_cmd;
1487
	state->sg = scat;
S
Sagi Grimberg 已提交
1488

1489 1490 1491
	if (count == 0)
		return 0;

B
Bart Van Assche 已提交
1492
	while (count) {
1493
		int i, n;
S
Sagi Grimberg 已提交
1494

1495
		n = srp_map_finish_fr(state, req, ch, count, &sg_offset);
1496 1497 1498
		if (unlikely(n < 0))
			return n;

B
Bart Van Assche 已提交
1499
		count -= n;
1500 1501 1502
		for (i = 0; i < n; i++)
			state->sg = sg_next(state->sg);
	}
S
Sagi Grimberg 已提交
1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518

	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),
1519
			     target->pd->unsafe_global_rkey);
1520
	}
1521

S
Sagi Grimberg 已提交
1522
	return 0;
1523 1524
}

1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540
/*
 * 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];
1541
	struct scatterlist idb_sg[1];
1542 1543 1544 1545 1546 1547 1548 1549 1550
	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;
1551 1552 1553

	if (dev->use_fast_reg) {
		state.sg = idb_sg;
1554
		sg_init_one(idb_sg, req->indirect_desc, idb_len);
1555
		idb_sg->dma_address = req->indirect_dma_addr; /* hack! */
1556 1557 1558
#ifdef CONFIG_NEED_SG_DMA_LENGTH
		idb_sg->dma_length = idb_sg->length;	      /* hack^2 */
#endif
1559
		ret = srp_map_finish_fr(&state, req, ch, 1, NULL);
1560 1561
		if (ret < 0)
			return ret;
1562
		WARN_ON_ONCE(ret < 1);
1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573
	} 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;
	}
1574 1575 1576

	*idb_rkey = idb_desc.key;

1577
	return 0;
1578 1579
}

1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603
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);
}

1604 1605 1606 1607 1608 1609 1610 1611 1612
/**
 * 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.
 */
1613
static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_rdma_ch *ch,
1614 1615
			struct srp_request *req)
{
1616
	struct srp_target_port *target = ch->target;
1617
	struct ib_pd *pd = target->pd;
1618
	struct scatterlist *scat;
1619
	struct srp_cmd *cmd = req->cmd->buf;
1620
	int len, nents, count, ret;
1621 1622
	struct srp_device *dev;
	struct ib_device *ibdev;
1623 1624
	struct srp_map_state state;
	struct srp_indirect_buf *indirect_hdr;
1625 1626
	u32 idb_len, table_len;
	__be32 idb_rkey;
1627
	u8 fmt;
1628

1629
	if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
1630 1631 1632 1633
		return sizeof (struct srp_cmd);

	if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
	    scmnd->sc_data_direction != DMA_TO_DEVICE) {
1634 1635 1636
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled data direction %d\n",
			     scmnd->sc_data_direction);
1637 1638 1639
		return -EINVAL;
	}

1640 1641
	nents = scsi_sg_count(scmnd);
	scat  = scsi_sglist(scmnd);
1642

1643
	dev = target->srp_host->srp_dev;
1644 1645 1646
	ibdev = dev->dev;

	count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
1647 1648
	if (unlikely(count == 0))
		return -EIO;
1649 1650 1651

	fmt = SRP_DATA_DESC_DIRECT;
	len = sizeof (struct srp_cmd) +	sizeof (struct srp_direct_buf);
1652

1653
	if (count == 1 && (pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) {
1654 1655 1656 1657 1658 1659
		/*
		 * 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.
		 */
1660
		struct srp_direct_buf *buf = (void *) cmd->add_data;
1661

1662
		buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
1663
		buf->key = cpu_to_be32(pd->unsafe_global_rkey);
1664
		buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
1665

1666
		req->nmdesc = 0;
1667 1668 1669
		goto map_complete;
	}

1670 1671 1672
	/*
	 * We have more than one scatter/gather entry, so build our indirect
	 * descriptor table, trying to merge as many entries as we can.
1673 1674 1675
	 */
	indirect_hdr = (void *) cmd->add_data;

1676 1677 1678
	ib_dma_sync_single_for_cpu(ibdev, req->indirect_dma_addr,
				   target->indirect_size, DMA_TO_DEVICE);

1679
	memset(&state, 0, sizeof(state));
B
Bart Van Assche 已提交
1680
	state.desc = req->indirect_desc;
S
Sagi Grimberg 已提交
1681
	if (dev->use_fast_reg)
1682
		ret = srp_map_sg_fr(&state, ch, req, scat, count);
S
Sagi Grimberg 已提交
1683
	else if (dev->use_fmr)
1684
		ret = srp_map_sg_fmr(&state, ch, req, scat, count);
S
Sagi Grimberg 已提交
1685
	else
1686 1687 1688 1689
		ret = srp_map_sg_dma(&state, ch, req, scat, count);
	req->nmdesc = state.nmdesc;
	if (ret < 0)
		goto unmap;
1690

1691 1692 1693
	{
		DEFINE_DYNAMIC_DEBUG_METADATA(ddm,
			"Memory mapping consistency check");
1694
		if (DYNAMIC_DEBUG_BRANCH(ddm))
1695 1696
			srp_check_mapping(&state, ch, req, scat, count);
	}
1697

1698 1699 1700 1701 1702
	/* 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.
1703 1704
	 */
	if (state.ndesc == 1) {
1705 1706
		/*
		 * Memory registration collapsed the sg-list into one entry,
1707 1708 1709
		 * so use a direct descriptor.
		 */
		struct srp_direct_buf *buf = (void *) cmd->add_data;
1710

1711
		*buf = req->indirect_desc[0];
1712
		goto map_complete;
1713 1714
	}

1715 1716 1717 1718
	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");
1719 1720
		ret = -EIO;
		goto unmap;
1721 1722 1723
	}

	count = min(state.ndesc, target->cmd_sg_cnt);
1724
	table_len = state.ndesc * sizeof (struct srp_direct_buf);
1725
	idb_len = sizeof(struct srp_indirect_buf) + table_len;
1726 1727 1728

	fmt = SRP_DATA_DESC_INDIRECT;
	len = sizeof(struct srp_cmd) + sizeof (struct srp_indirect_buf);
1729
	len += count * sizeof (struct srp_direct_buf);
1730

1731 1732
	memcpy(indirect_hdr->desc_list, req->indirect_desc,
	       count * sizeof (struct srp_direct_buf));
1733

1734
	if (!(pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) {
1735 1736 1737
		ret = srp_map_idb(ch, req, state.gen.next, state.gen.end,
				  idb_len, &idb_rkey);
		if (ret < 0)
1738
			goto unmap;
1739 1740
		req->nmdesc++;
	} else {
1741
		idb_rkey = cpu_to_be32(pd->unsafe_global_rkey);
1742 1743
	}

1744
	indirect_hdr->table_desc.va = cpu_to_be64(req->indirect_dma_addr);
1745
	indirect_hdr->table_desc.key = idb_rkey;
1746 1747 1748 1749
	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)
1750
		cmd->data_out_desc_cnt = count;
1751
	else
1752 1753 1754 1755
		cmd->data_in_desc_cnt = count;

	ib_dma_sync_single_for_device(ibdev, req->indirect_dma_addr, table_len,
				      DMA_TO_DEVICE);
1756 1757

map_complete:
1758 1759 1760 1761 1762 1763
	if (scmnd->sc_data_direction == DMA_TO_DEVICE)
		cmd->buf_fmt = fmt << 4;
	else
		cmd->buf_fmt = fmt;

	return len;
1764 1765 1766

unmap:
	srp_unmap_data(scmnd, ch, req);
1767 1768
	if (ret == -ENOMEM && req->nmdesc >= target->mr_pool_size)
		ret = -E2BIG;
1769
	return ret;
1770 1771
}

1772 1773 1774
/*
 * Return an IU and possible credit to the free pool
 */
1775
static void srp_put_tx_iu(struct srp_rdma_ch *ch, struct srp_iu *iu,
1776 1777 1778 1779
			  enum srp_iu_type iu_type)
{
	unsigned long flags;

1780 1781
	spin_lock_irqsave(&ch->lock, flags);
	list_add(&iu->list, &ch->free_tx);
1782
	if (iu_type != SRP_IU_RSP)
1783 1784
		++ch->req_lim;
	spin_unlock_irqrestore(&ch->lock, flags);
1785 1786
}

1787
/*
1788
 * Must be called with ch->lock held to protect req_lim and free_tx.
1789
 * If IU is not sent, it must be returned using srp_put_tx_iu().
1790 1791 1792 1793 1794 1795 1796 1797 1798 1799
 *
 * 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.
 */
1800
static struct srp_iu *__srp_get_tx_iu(struct srp_rdma_ch *ch,
1801 1802
				      enum srp_iu_type iu_type)
{
1803
	struct srp_target_port *target = ch->target;
1804 1805 1806
	s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
	struct srp_iu *iu;

C
Christoph Hellwig 已提交
1807
	ib_process_cq_direct(ch->send_cq, -1);
1808

1809
	if (list_empty(&ch->free_tx))
1810 1811 1812
		return NULL;

	/* Initiator responses to target requests do not consume credits */
1813
	if (iu_type != SRP_IU_RSP) {
1814
		if (ch->req_lim <= rsv) {
1815 1816 1817 1818
			++target->zero_req_lim;
			return NULL;
		}

1819
		--ch->req_lim;
1820 1821
	}

1822
	iu = list_first_entry(&ch->free_tx, struct srp_iu, list);
1823
	list_del(&iu->list);
1824 1825 1826
	return iu;
}

C
Christoph Hellwig 已提交
1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839
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;
	}

	list_add(&iu->list, &ch->free_tx);
}

1840
static int srp_post_send(struct srp_rdma_ch *ch, struct srp_iu *iu, int len)
1841
{
1842
	struct srp_target_port *target = ch->target;
1843 1844 1845 1846 1847
	struct ib_sge list;
	struct ib_send_wr wr, *bad_wr;

	list.addr   = iu->dma;
	list.length = len;
1848
	list.lkey   = target->lkey;
1849

C
Christoph Hellwig 已提交
1850 1851
	iu->cqe.done = srp_send_done;

1852
	wr.next       = NULL;
C
Christoph Hellwig 已提交
1853
	wr.wr_cqe     = &iu->cqe;
1854 1855 1856 1857 1858
	wr.sg_list    = &list;
	wr.num_sge    = 1;
	wr.opcode     = IB_WR_SEND;
	wr.send_flags = IB_SEND_SIGNALED;

1859
	return ib_post_send(ch->qp, &wr, &bad_wr);
1860 1861
}

1862
static int srp_post_recv(struct srp_rdma_ch *ch, struct srp_iu *iu)
1863
{
1864
	struct srp_target_port *target = ch->target;
1865
	struct ib_recv_wr wr, *bad_wr;
1866
	struct ib_sge list;
1867 1868 1869

	list.addr   = iu->dma;
	list.length = iu->size;
1870
	list.lkey   = target->lkey;
1871

C
Christoph Hellwig 已提交
1872 1873
	iu->cqe.done = srp_recv_done;

1874
	wr.next     = NULL;
C
Christoph Hellwig 已提交
1875
	wr.wr_cqe   = &iu->cqe;
1876 1877 1878
	wr.sg_list  = &list;
	wr.num_sge  = 1;

1879
	return ib_post_recv(ch->qp, &wr, &bad_wr);
1880 1881
}

1882
static void srp_process_rsp(struct srp_rdma_ch *ch, struct srp_rsp *rsp)
1883
{
1884
	struct srp_target_port *target = ch->target;
1885 1886 1887 1888 1889
	struct srp_request *req;
	struct scsi_cmnd *scmnd;
	unsigned long flags;

	if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
1890 1891 1892
		spin_lock_irqsave(&ch->lock, flags);
		ch->req_lim += be32_to_cpu(rsp->req_lim_delta);
		spin_unlock_irqrestore(&ch->lock, flags);
1893

1894
		ch->tsk_mgmt_status = -1;
1895
		if (be32_to_cpu(rsp->resp_data_len) >= 4)
1896 1897
			ch->tsk_mgmt_status = rsp->data[3];
		complete(&ch->tsk_mgmt_done);
1898
	} else {
B
Bart Van Assche 已提交
1899 1900 1901 1902 1903
		scmnd = scsi_host_find_tag(target->scsi_host, rsp->tag);
		if (scmnd) {
			req = (void *)scmnd->host_scribble;
			scmnd = srp_claim_req(ch, req, NULL, scmnd);
		}
B
Bart Van Assche 已提交
1904
		if (!scmnd) {
1905
			shost_printk(KERN_ERR, target->scsi_host,
B
Bart Van Assche 已提交
1906 1907
				     "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
1908

1909 1910 1911
			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
1912 1913 1914

			return;
		}
1915 1916 1917 1918 1919 1920 1921 1922 1923
		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
1924
		if (unlikely(rsp->flags & SRP_RSP_FLAG_DIUNDER))
1925
			scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
B
Bart Van Assche 已提交
1926 1927 1928 1929 1930 1931
		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));
1932

1933
		srp_free_req(ch, req, scmnd,
B
Bart Van Assche 已提交
1934 1935
			     be32_to_cpu(rsp->req_lim_delta));

1936 1937
		scmnd->host_scribble = NULL;
		scmnd->scsi_done(scmnd);
1938 1939 1940
	}
}

1941
static int srp_response_common(struct srp_rdma_ch *ch, s32 req_delta,
1942 1943
			       void *rsp, int len)
{
1944
	struct srp_target_port *target = ch->target;
1945
	struct ib_device *dev = target->srp_host->srp_dev->dev;
1946 1947
	unsigned long flags;
	struct srp_iu *iu;
1948
	int err;
1949

1950 1951 1952 1953
	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);
1954

1955 1956 1957
	if (!iu) {
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "no IU available to send response\n");
1958
		return 1;
1959 1960 1961 1962 1963 1964
	}

	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);

1965
	err = srp_post_send(ch, iu, len);
1966
	if (err) {
1967 1968
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "unable to post response: %d\n", err);
1969
		srp_put_tx_iu(ch, iu, SRP_IU_RSP);
1970
	}
1971 1972 1973 1974

	return err;
}

1975
static void srp_process_cred_req(struct srp_rdma_ch *ch,
1976 1977 1978 1979 1980 1981 1982 1983
				 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);

1984 1985
	if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
		shost_printk(KERN_ERR, ch->target->scsi_host, PFX
1986 1987 1988
			     "problems processing SRP_CRED_REQ\n");
}

1989
static void srp_process_aer_req(struct srp_rdma_ch *ch,
1990 1991
				struct srp_aer_req *req)
{
1992
	struct srp_target_port *target = ch->target;
1993 1994 1995 1996 1997 1998 1999
	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
2000
		     "ignoring AER for LUN %llu\n", scsilun_to_int(&req->lun));
2001

2002
	if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
2003 2004 2005 2006
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "problems processing SRP_AER_REQ\n");
}

C
Christoph Hellwig 已提交
2007
static void srp_recv_done(struct ib_cq *cq, struct ib_wc *wc)
2008
{
C
Christoph Hellwig 已提交
2009 2010
	struct srp_iu *iu = container_of(wc->wr_cqe, struct srp_iu, cqe);
	struct srp_rdma_ch *ch = cq->cq_context;
2011
	struct srp_target_port *target = ch->target;
2012
	struct ib_device *dev = target->srp_host->srp_dev->dev;
2013
	int res;
2014 2015
	u8 opcode;

C
Christoph Hellwig 已提交
2016 2017 2018 2019 2020
	if (unlikely(wc->status != IB_WC_SUCCESS)) {
		srp_handle_qp_err(cq, wc, "RECV");
		return;
	}

2021
	ib_dma_sync_single_for_cpu(dev, iu->dma, ch->max_ti_iu_len,
2022
				   DMA_FROM_DEVICE);
2023 2024 2025 2026

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

	if (0) {
2027 2028
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "recv completion, opcode 0x%02x\n", opcode);
B
Bart Van Assche 已提交
2029 2030
		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
			       iu->buf, wc->byte_len, true);
2031 2032 2033 2034
	}

	switch (opcode) {
	case SRP_RSP:
2035
		srp_process_rsp(ch, iu->buf);
2036 2037
		break;

2038
	case SRP_CRED_REQ:
2039
		srp_process_cred_req(ch, iu->buf);
2040 2041 2042
		break;

	case SRP_AER_REQ:
2043
		srp_process_aer_req(ch, iu->buf);
2044 2045
		break;

2046 2047
	case SRP_T_LOGOUT:
		/* XXX Handle target logout */
2048 2049
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Got target logout request\n");
2050 2051 2052
		break;

	default:
2053 2054
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled SRP opcode 0x%02x\n", opcode);
2055 2056 2057
		break;
	}

2058
	ib_dma_sync_single_for_device(dev, iu->dma, ch->max_ti_iu_len,
2059
				      DMA_FROM_DEVICE);
2060

2061
	res = srp_post_recv(ch, iu);
2062 2063 2064
	if (res != 0)
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "Recv failed with error code %d\n", res);
2065 2066
}

2067 2068
/**
 * srp_tl_err_work() - handle a transport layer error
2069
 * @work: Work structure embedded in an SRP target port.
2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082
 *
 * 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
2083 2084
static void srp_handle_qp_err(struct ib_cq *cq, struct ib_wc *wc,
		const char *opname)
2085
{
C
Christoph Hellwig 已提交
2086
	struct srp_rdma_ch *ch = cq->cq_context;
2087 2088
	struct srp_target_port *target = ch->target;

2089
	if (ch->connected && !target->qp_in_error) {
C
Christoph Hellwig 已提交
2090 2091 2092 2093
		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);
2094
		queue_work(system_long_wq, &target->tl_err_work);
2095
	}
2096 2097 2098
	target->qp_in_error = true;
}

2099
static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
2100
{
2101
	struct srp_target_port *target = host_to_target(shost);
2102
	struct srp_rport *rport = target->rport;
2103
	struct srp_rdma_ch *ch;
2104 2105 2106
	struct srp_request *req;
	struct srp_iu *iu;
	struct srp_cmd *cmd;
2107
	struct ib_device *dev;
2108
	unsigned long flags;
B
Bart Van Assche 已提交
2109 2110
	u32 tag;
	u16 idx;
2111
	int len, ret;
2112 2113 2114 2115 2116 2117 2118 2119 2120 2121
	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);
2122

2123 2124 2125
	scmnd->result = srp_chkready(target->rport);
	if (unlikely(scmnd->result))
		goto err;
2126

B
Bart Van Assche 已提交
2127 2128
	WARN_ON_ONCE(scmnd->request->tag < 0);
	tag = blk_mq_unique_tag(scmnd->request);
B
Bart Van Assche 已提交
2129
	ch = &target->ch[blk_mq_unique_tag_to_hwq(tag)];
B
Bart Van Assche 已提交
2130 2131 2132 2133
	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);
2134 2135 2136 2137

	spin_lock_irqsave(&ch->lock, flags);
	iu = __srp_get_tx_iu(ch, SRP_IU_CMD);
	spin_unlock_irqrestore(&ch->lock, flags);
2138

B
Bart Van Assche 已提交
2139 2140 2141 2142
	if (!iu)
		goto err;

	req = &ch->req_ring[idx];
2143
	dev = target->srp_host->srp_dev->dev;
2144
	ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len,
2145
				   DMA_TO_DEVICE);
2146

2147
	scmnd->host_scribble = (void *) req;
2148 2149 2150 2151 2152

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

	cmd->opcode = SRP_CMD;
B
Bart Van Assche 已提交
2153
	int_to_scsilun(scmnd->device->lun, &cmd->lun);
B
Bart Van Assche 已提交
2154
	cmd->tag    = tag;
2155 2156 2157 2158 2159
	memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);

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

2160
	len = srp_map_data(scmnd, ch, req);
2161
	if (len < 0) {
2162
		shost_printk(KERN_ERR, target->scsi_host,
2163 2164 2165 2166
			     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
2167
		 * max_pages_per_mr sg-list elements, tell the SCSI mid-layer
2168 2169 2170 2171
		 * to reduce queue depth temporarily.
		 */
		scmnd->result = len == -ENOMEM ?
			DID_OK << 16 | QUEUE_FULL << 1 : DID_ERROR << 16;
2172
		goto err_iu;
2173 2174
	}

2175
	ib_dma_sync_single_for_device(dev, iu->dma, target->max_iu_len,
2176
				      DMA_TO_DEVICE);
2177

2178
	if (srp_post_send(ch, iu, len)) {
2179
		shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
2180 2181 2182
		goto err_unmap;
	}

2183 2184
	ret = 0;

2185 2186 2187 2188
unlock_rport:
	if (in_scsi_eh)
		mutex_unlock(&rport->mutex);

2189
	return ret;
2190 2191

err_unmap:
2192
	srp_unmap_data(scmnd, ch, req);
2193

2194
err_iu:
2195
	srp_put_tx_iu(ch, iu, SRP_IU_CMD);
2196

2197 2198 2199 2200 2201 2202
	/*
	 * Avoid that the loops that iterate over the request ring can
	 * encounter a dangling SCSI command pointer.
	 */
	req->scmnd = NULL;

2203 2204 2205 2206 2207 2208 2209
err:
	if (scmnd->result) {
		scmnd->scsi_done(scmnd);
		ret = 0;
	} else {
		ret = SCSI_MLQUEUE_HOST_BUSY;
	}
2210

2211
	goto unlock_rport;
2212 2213
}

2214 2215
/*
 * Note: the resources allocated in this function are freed in
2216
 * srp_free_ch_ib().
2217
 */
2218
static int srp_alloc_iu_bufs(struct srp_rdma_ch *ch)
2219
{
2220
	struct srp_target_port *target = ch->target;
2221 2222
	int i;

2223 2224 2225
	ch->rx_ring = kcalloc(target->queue_size, sizeof(*ch->rx_ring),
			      GFP_KERNEL);
	if (!ch->rx_ring)
2226
		goto err_no_ring;
2227 2228 2229
	ch->tx_ring = kcalloc(target->queue_size, sizeof(*ch->tx_ring),
			      GFP_KERNEL);
	if (!ch->tx_ring)
2230 2231 2232
		goto err_no_ring;

	for (i = 0; i < target->queue_size; ++i) {
2233 2234 2235 2236
		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])
2237 2238 2239
			goto err;
	}

2240
	for (i = 0; i < target->queue_size; ++i) {
2241 2242 2243 2244
		ch->tx_ring[i] = srp_alloc_iu(target->srp_host,
					      target->max_iu_len,
					      GFP_KERNEL, DMA_TO_DEVICE);
		if (!ch->tx_ring[i])
2245
			goto err;
2246

2247
		list_add(&ch->tx_ring[i]->list, &ch->free_tx);
2248 2249 2250 2251 2252
	}

	return 0;

err:
2253
	for (i = 0; i < target->queue_size; ++i) {
2254 2255
		srp_free_iu(target->srp_host, ch->rx_ring[i]);
		srp_free_iu(target->srp_host, ch->tx_ring[i]);
2256 2257
	}

2258 2259

err_no_ring:
2260 2261 2262 2263
	kfree(ch->tx_ring);
	ch->tx_ring = NULL;
	kfree(ch->rx_ring);
	ch->rx_ring = NULL;
2264

2265 2266 2267
	return -ENOMEM;
}

2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294
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;
}

2295
static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
2296
			       const struct srp_login_rsp *lrsp,
2297
			       struct srp_rdma_ch *ch)
2298
{
2299
	struct srp_target_port *target = ch->target;
2300 2301 2302 2303 2304 2305
	struct ib_qp_attr *qp_attr = NULL;
	int attr_mask = 0;
	int ret;
	int i;

	if (lrsp->opcode == SRP_LOGIN_RSP) {
2306 2307
		ch->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len);
		ch->req_lim       = be32_to_cpu(lrsp->req_lim_delta);
2308 2309 2310 2311 2312 2313

		/*
		 * Reserve credits for task management so we don't
		 * bounce requests back to the SCSI mid-layer.
		 */
		target->scsi_host->can_queue
2314
			= min(ch->req_lim - SRP_TSK_MGMT_SQ_SIZE,
2315
			      target->scsi_host->can_queue);
2316 2317 2318
		target->scsi_host->cmd_per_lun
			= min_t(int, target->scsi_host->can_queue,
				target->scsi_host->cmd_per_lun);
2319 2320 2321 2322 2323 2324 2325
	} else {
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);
		ret = -ECONNRESET;
		goto error;
	}

2326 2327
	if (!ch->rx_ring) {
		ret = srp_alloc_iu_bufs(ch);
2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341
		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;

2342
	ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2343 2344 2345
	if (ret)
		goto error_free;

2346
	for (i = 0; i < target->queue_size; i++) {
2347 2348 2349
		struct srp_iu *iu = ch->rx_ring[i];

		ret = srp_post_recv(ch, iu);
2350 2351 2352 2353 2354 2355 2356 2357 2358
		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;

2359 2360
	target->rq_tmo_jiffies = srp_compute_rq_tmo(qp_attr, attr_mask);

2361
	ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2362 2363 2364 2365 2366 2367 2368 2369 2370
	if (ret)
		goto error_free;

	ret = ib_send_cm_rtu(cm_id, NULL, 0);

error_free:
	kfree(qp_attr);

error:
2371
	ch->status = ret;
2372 2373
}

2374 2375
static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
			       struct ib_cm_event *event,
2376
			       struct srp_rdma_ch *ch)
2377
{
2378
	struct srp_target_port *target = ch->target;
2379
	struct Scsi_Host *shost = target->scsi_host;
2380 2381 2382 2383 2384 2385
	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;
2386 2387
		ch->path.dlid = cpi->redirect_lid;
		ch->path.pkey = cpi->redirect_pkey;
2388
		cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
2389
		memcpy(ch->path.dgid.raw, cpi->redirect_gid, 16);
2390

2391
		ch->status = ch->path.dlid ?
2392 2393 2394 2395
			SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
		break;

	case IB_CM_REJ_PORT_REDIRECT:
2396
		if (srp_target_is_topspin(target)) {
2397 2398 2399 2400 2401
			/*
			 * Topspin/Cisco SRP gateways incorrectly send
			 * reject reason code 25 when they mean 24
			 * (port redirect).
			 */
2402
			memcpy(ch->path.dgid.raw,
2403 2404
			       event->param.rej_rcvd.ari, 16);

2405 2406
			shost_printk(KERN_DEBUG, shost,
				     PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
2407 2408
				     be64_to_cpu(ch->path.dgid.global.subnet_prefix),
				     be64_to_cpu(ch->path.dgid.global.interface_id));
2409

2410
			ch->status = SRP_PORT_REDIRECT;
2411
		} else {
2412 2413
			shost_printk(KERN_WARNING, shost,
				     "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
2414
			ch->status = -ECONNRESET;
2415 2416 2417 2418
		}
		break;

	case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
2419 2420
		shost_printk(KERN_WARNING, shost,
			    "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
2421
		ch->status = -ECONNRESET;
2422 2423 2424 2425 2426 2427 2428 2429 2430
		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)
2431 2432
				shost_printk(KERN_WARNING, shost,
					     PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
2433
			else
B
Bart Van Assche 已提交
2434 2435
				shost_printk(KERN_WARNING, shost, PFX
					     "SRP LOGIN from %pI6 to %pI6 REJECTED, reason 0x%08x\n",
2436 2437
					     target->sgid.raw,
					     target->orig_dgid.raw, reason);
2438
		} else
2439 2440 2441
			shost_printk(KERN_WARNING, shost,
				     "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
				     " opcode 0x%02x\n", opcode);
2442
		ch->status = -ECONNRESET;
2443 2444
		break;

D
David Dillow 已提交
2445 2446
	case IB_CM_REJ_STALE_CONN:
		shost_printk(KERN_WARNING, shost, "  REJ reason: stale connection\n");
2447
		ch->status = SRP_STALE_CONN;
D
David Dillow 已提交
2448 2449
		break;

2450
	default:
2451 2452
		shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
			     event->param.rej_rcvd.reason);
2453
		ch->status = -ECONNRESET;
2454 2455 2456 2457 2458
	}
}

static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
{
2459 2460
	struct srp_rdma_ch *ch = cm_id->context;
	struct srp_target_port *target = ch->target;
2461 2462 2463 2464
	int comp = 0;

	switch (event->event) {
	case IB_CM_REQ_ERROR:
2465 2466
		shost_printk(KERN_DEBUG, target->scsi_host,
			     PFX "Sending CM REQ failed\n");
2467
		comp = 1;
2468
		ch->status = -ECONNRESET;
2469 2470 2471 2472
		break;

	case IB_CM_REP_RECEIVED:
		comp = 1;
2473
		srp_cm_rep_handler(cm_id, event->private_data, ch);
2474 2475 2476
		break;

	case IB_CM_REJ_RECEIVED:
2477
		shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
2478 2479
		comp = 1;

2480
		srp_cm_rej_handler(cm_id, event, ch);
2481 2482
		break;

2483
	case IB_CM_DREQ_RECEIVED:
2484 2485
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "DREQ received - connection closed\n");
2486
		ch->connected = false;
2487
		if (ib_send_cm_drep(cm_id, NULL, 0))
2488 2489
			shost_printk(KERN_ERR, target->scsi_host,
				     PFX "Sending CM DREP failed\n");
2490
		queue_work(system_long_wq, &target->tl_err_work);
2491 2492 2493
		break;

	case IB_CM_TIMEWAIT_EXIT:
2494 2495
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "connection closed\n");
2496
		comp = 1;
2497

2498
		ch->status = 0;
2499 2500
		break;

2501 2502 2503 2504 2505
	case IB_CM_MRA_RECEIVED:
	case IB_CM_DREQ_ERROR:
	case IB_CM_DREP_RECEIVED:
		break;

2506
	default:
2507 2508
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled CM event %d\n", event->event);
2509 2510 2511 2512
		break;
	}

	if (comp)
2513
		complete(&ch->done);
2514 2515 2516 2517

	return 0;
}

2518 2519 2520 2521 2522 2523 2524 2525
/**
 * srp_change_queue_depth - setting device queue depth
 * @sdev: scsi device struct
 * @qdepth: requested queue depth
 *
 * Returns queue depth.
 */
static int
2526
srp_change_queue_depth(struct scsi_device *sdev, int qdepth)
2527
{
2528
	if (!sdev->tagged_supported)
2529
		qdepth = 1;
2530
	return scsi_change_queue_depth(sdev, qdepth);
2531 2532
}

B
Bart Van Assche 已提交
2533 2534
static int srp_send_tsk_mgmt(struct srp_rdma_ch *ch, u64 req_tag, u64 lun,
			     u8 func)
2535
{
2536
	struct srp_target_port *target = ch->target;
2537
	struct srp_rport *rport = target->rport;
2538
	struct ib_device *dev = target->srp_host->srp_dev->dev;
2539 2540 2541
	struct srp_iu *iu;
	struct srp_tsk_mgmt *tsk_mgmt;

2542
	if (!ch->connected || target->qp_in_error)
2543 2544
		return -1;

2545
	init_completion(&ch->tsk_mgmt_done);
2546

2547
	/*
2548
	 * Lock the rport mutex to avoid that srp_create_ch_ib() is
2549 2550 2551
	 * invoked while a task management function is being sent.
	 */
	mutex_lock(&rport->mutex);
2552 2553 2554
	spin_lock_irq(&ch->lock);
	iu = __srp_get_tx_iu(ch, SRP_IU_TSK_MGMT);
	spin_unlock_irq(&ch->lock);
2555

2556 2557 2558
	if (!iu) {
		mutex_unlock(&rport->mutex);

2559
		return -1;
2560
	}
2561

2562 2563
	ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
				   DMA_TO_DEVICE);
2564 2565 2566 2567
	tsk_mgmt = iu->buf;
	memset(tsk_mgmt, 0, sizeof *tsk_mgmt);

	tsk_mgmt->opcode 	= SRP_TSK_MGMT;
B
Bart Van Assche 已提交
2568
	int_to_scsilun(lun, &tsk_mgmt->lun);
2569
	tsk_mgmt->tag		= req_tag | SRP_TAG_TSK_MGMT;
2570
	tsk_mgmt->tsk_mgmt_func = func;
2571
	tsk_mgmt->task_tag	= req_tag;
2572

2573 2574
	ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
				      DMA_TO_DEVICE);
2575 2576
	if (srp_post_send(ch, iu, sizeof(*tsk_mgmt))) {
		srp_put_tx_iu(ch, iu, SRP_IU_TSK_MGMT);
2577 2578
		mutex_unlock(&rport->mutex);

2579 2580
		return -1;
	}
2581
	mutex_unlock(&rport->mutex);
2582

2583
	if (!wait_for_completion_timeout(&ch->tsk_mgmt_done,
2584
					 msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
2585
		return -1;
2586

2587 2588 2589
	return 0;
}

2590 2591
static int srp_abort(struct scsi_cmnd *scmnd)
{
2592
	struct srp_target_port *target = host_to_target(scmnd->device->host);
2593
	struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
B
Bart Van Assche 已提交
2594
	u32 tag;
B
Bart Van Assche 已提交
2595
	u16 ch_idx;
2596
	struct srp_rdma_ch *ch;
2597
	int ret;
2598

2599
	shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
2600

B
Bart Van Assche 已提交
2601
	if (!req)
2602
		return SUCCESS;
B
Bart Van Assche 已提交
2603
	tag = blk_mq_unique_tag(scmnd->request);
B
Bart Van Assche 已提交
2604 2605 2606 2607 2608 2609 2610 2611
	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
2612
	if (srp_send_tsk_mgmt(ch, tag, scmnd->device->lun,
2613
			      SRP_TSK_ABORT_TASK) == 0)
2614
		ret = SUCCESS;
2615
	else if (target->rport->state == SRP_RPORT_LOST)
2616
		ret = FAST_IO_FAIL;
2617 2618
	else
		ret = FAILED;
2619
	srp_free_req(ch, req, scmnd, 0);
B
Bart Van Assche 已提交
2620
	scmnd->result = DID_ABORT << 16;
2621
	scmnd->scsi_done(scmnd);
2622

2623
	return ret;
2624 2625 2626 2627
}

static int srp_reset_device(struct scsi_cmnd *scmnd)
{
2628
	struct srp_target_port *target = host_to_target(scmnd->device->host);
B
Bart Van Assche 已提交
2629
	struct srp_rdma_ch *ch;
2630
	int i;
2631

2632
	shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
2633

B
Bart Van Assche 已提交
2634
	ch = &target->ch[0];
2635
	if (srp_send_tsk_mgmt(ch, SRP_TAG_NO_REQ, scmnd->device->lun,
2636
			      SRP_TSK_LUN_RESET))
2637
		return FAILED;
2638
	if (ch->tsk_mgmt_status)
2639 2640
		return FAILED;

B
Bart Van Assche 已提交
2641 2642 2643 2644
	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];
2645

B
Bart Van Assche 已提交
2646 2647
			srp_finish_req(ch, req, scmnd->device, DID_RESET << 16);
		}
2648
	}
2649 2650

	return SUCCESS;
2651 2652 2653 2654 2655 2656
}

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

2657
	shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
2658

2659
	return srp_reconnect_rport(target->rport) == 0 ? SUCCESS : FAILED;
2660 2661
}

2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675
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;
	struct ib_device *ibdev = srp_dev->dev;

	if (!(ibdev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG))
		blk_queue_virt_boundary(sdev->request_queue,
					~srp_dev->mr_page_mask);

	return 0;
}

2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690
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;
}

2691 2692
static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
			   char *buf)
2693
{
2694
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2695

2696
	return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->id_ext));
2697 2698
}

2699 2700
static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
			     char *buf)
2701
{
2702
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2703

2704
	return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->ioc_guid));
2705 2706
}

2707 2708
static ssize_t show_service_id(struct device *dev,
			       struct device_attribute *attr, char *buf)
2709
{
2710
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2711

2712
	return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->service_id));
2713 2714
}

2715 2716
static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
			 char *buf)
2717
{
2718
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2719

2720
	return sprintf(buf, "0x%04x\n", be16_to_cpu(target->pkey));
2721 2722
}

B
Bart Van Assche 已提交
2723 2724 2725 2726 2727
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));

2728
	return sprintf(buf, "%pI6\n", target->sgid.raw);
B
Bart Van Assche 已提交
2729 2730
}

2731 2732
static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
			 char *buf)
2733
{
2734
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
B
Bart Van Assche 已提交
2735
	struct srp_rdma_ch *ch = &target->ch[0];
2736

2737
	return sprintf(buf, "%pI6\n", ch->path.dgid.raw);
2738 2739
}

2740 2741
static ssize_t show_orig_dgid(struct device *dev,
			      struct device_attribute *attr, char *buf)
2742
{
2743
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2744

2745
	return sprintf(buf, "%pI6\n", target->orig_dgid.raw);
2746 2747
}

2748 2749 2750 2751
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
2752 2753
	struct srp_rdma_ch *ch;
	int i, req_lim = INT_MAX;
2754

B
Bart Van Assche 已提交
2755 2756 2757 2758 2759
	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);
2760 2761
}

2762 2763
static ssize_t show_zero_req_lim(struct device *dev,
				 struct device_attribute *attr, char *buf)
2764
{
2765
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2766 2767 2768 2769

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

2770 2771
static ssize_t show_local_ib_port(struct device *dev,
				  struct device_attribute *attr, char *buf)
2772
{
2773
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2774 2775 2776 2777

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

2778 2779
static ssize_t show_local_ib_device(struct device *dev,
				    struct device_attribute *attr, char *buf)
2780
{
2781
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
2782

2783
	return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
2784 2785
}

B
Bart Van Assche 已提交
2786 2787 2788 2789 2790 2791 2792 2793
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);
}

2794 2795 2796 2797 2798 2799 2800 2801
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);
}

2802 2803 2804 2805 2806 2807 2808 2809
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);
}

2810 2811 2812 2813 2814 2815 2816 2817
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);
}

2818 2819 2820 2821 2822 2823 2824 2825
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");
}

2826 2827 2828 2829
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
2830
static DEVICE_ATTR(sgid,	    S_IRUGO, show_sgid,		   NULL);
2831 2832
static DEVICE_ATTR(dgid,	    S_IRUGO, show_dgid,		   NULL);
static DEVICE_ATTR(orig_dgid,	    S_IRUGO, show_orig_dgid,	   NULL);
2833
static DEVICE_ATTR(req_lim,         S_IRUGO, show_req_lim,         NULL);
2834 2835 2836
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
2837
static DEVICE_ATTR(ch_count,        S_IRUGO, show_ch_count,        NULL);
2838
static DEVICE_ATTR(comp_vector,     S_IRUGO, show_comp_vector,     NULL);
2839
static DEVICE_ATTR(tl_retry_count,  S_IRUGO, show_tl_retry_count,  NULL);
2840
static DEVICE_ATTR(cmd_sg_entries,  S_IRUGO, show_cmd_sg_entries,  NULL);
2841
static DEVICE_ATTR(allow_ext_sg,    S_IRUGO, show_allow_ext_sg,    NULL);
2842 2843 2844 2845 2846 2847

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
2848
	&dev_attr_sgid,
2849 2850
	&dev_attr_dgid,
	&dev_attr_orig_dgid,
2851
	&dev_attr_req_lim,
2852 2853 2854
	&dev_attr_zero_req_lim,
	&dev_attr_local_ib_port,
	&dev_attr_local_ib_device,
B
Bart Van Assche 已提交
2855
	&dev_attr_ch_count,
2856
	&dev_attr_comp_vector,
2857
	&dev_attr_tl_retry_count,
2858
	&dev_attr_cmd_sg_entries,
2859
	&dev_attr_allow_ext_sg,
2860 2861 2862
	NULL
};

2863 2864
static struct scsi_host_template srp_template = {
	.module				= THIS_MODULE,
R
Roland Dreier 已提交
2865 2866
	.name				= "InfiniBand SRP initiator",
	.proc_name			= DRV_NAME,
2867
	.slave_alloc			= srp_slave_alloc,
2868
	.slave_configure		= srp_slave_configure,
2869 2870
	.info				= srp_target_info,
	.queuecommand			= srp_queuecommand,
2871
	.change_queue_depth             = srp_change_queue_depth,
2872 2873 2874
	.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
2875
	.skip_settle_delay		= true,
2876
	.sg_tablesize			= SRP_DEF_SG_TABLESIZE,
2877
	.can_queue			= SRP_DEFAULT_CMD_SQ_SIZE,
2878
	.this_id			= -1,
2879
	.cmd_per_lun			= SRP_DEFAULT_CMD_SQ_SIZE,
2880
	.use_clustering			= ENABLE_CLUSTERING,
B
Bart Van Assche 已提交
2881
	.shost_attrs			= srp_host_attrs,
2882
	.track_queue_depth		= 1,
2883 2884
};

2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895
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;
}

2896 2897 2898 2899 2900 2901 2902
/*
 * 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.
 */
2903 2904
static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
{
2905 2906 2907
	struct srp_rport_identifiers ids;
	struct srp_rport *rport;

2908
	target->state = SRP_TARGET_SCANNING;
2909
	sprintf(target->target_name, "SRP.T10:%016llX",
2910
		be64_to_cpu(target->id_ext));
2911

2912
	if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
2913 2914
		return -ENODEV;

2915 2916
	memcpy(ids.port_id, &target->id_ext, 8);
	memcpy(ids.port_id + 8, &target->ioc_guid, 8);
2917
	ids.roles = SRP_RPORT_ROLE_TARGET;
2918 2919 2920 2921 2922 2923
	rport = srp_rport_add(target->scsi_host, &ids);
	if (IS_ERR(rport)) {
		scsi_remove_host(target->scsi_host);
		return PTR_ERR(rport);
	}

2924
	rport->lld_data = target;
2925
	target->rport = rport;
2926

2927
	spin_lock(&host->target_lock);
2928
	list_add_tail(&target->list, &host->target_list);
2929
	spin_unlock(&host->target_lock);
2930 2931

	scsi_scan_target(&target->scsi_host->shost_gendev,
2932
			 0, target->scsi_id, SCAN_WILD_CARD, SCSI_SCAN_INITIAL);
2933

2934 2935
	if (srp_connected_ch(target) < target->ch_count ||
	    target->qp_in_error) {
2936 2937 2938 2939 2940 2941
		shost_printk(KERN_INFO, target->scsi_host,
			     PFX "SCSI scan failed - removing SCSI host\n");
		srp_queue_remove_work(target);
		goto out;
	}

2942
	pr_debug("%s: SCSI scan succeeded - detected %d LUNs\n",
2943 2944 2945 2946 2947 2948 2949 2950 2951
		 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:
2952 2953 2954
	return 0;
}

2955
static void srp_release_dev(struct device *dev)
2956 2957
{
	struct srp_host *host =
2958
		container_of(dev, struct srp_host, dev);
2959 2960 2961 2962 2963 2964

	complete(&host->released);
}

static struct class srp_class = {
	.name    = "infiniband_srp",
2965
	.dev_release = srp_release_dev
2966 2967
};

2968 2969
/**
 * srp_conn_unique() - check whether the connection to a target is unique
2970 2971
 * @host:   SRP host.
 * @target: SRP target port.
2972 2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999
 */
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;
}

3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015
/*
 * 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,
3016
	SRP_OPT_MAX_CMD_PER_LUN	= 1 << 6,
3017
	SRP_OPT_IO_CLASS	= 1 << 7,
3018
	SRP_OPT_INITIATOR_EXT	= 1 << 8,
3019
	SRP_OPT_CMD_SG_ENTRIES	= 1 << 9,
3020 3021
	SRP_OPT_ALLOW_EXT_SG	= 1 << 10,
	SRP_OPT_SG_TABLESIZE	= 1 << 11,
3022
	SRP_OPT_COMP_VECTOR	= 1 << 12,
3023
	SRP_OPT_TL_RETRY_COUNT	= 1 << 13,
3024
	SRP_OPT_QUEUE_SIZE	= 1 << 14,
3025 3026 3027 3028 3029 3030 3031
	SRP_OPT_ALL		= (SRP_OPT_ID_EXT	|
				   SRP_OPT_IOC_GUID	|
				   SRP_OPT_DGID		|
				   SRP_OPT_PKEY		|
				   SRP_OPT_SERVICE_ID),
};

3032
static const match_table_t srp_opt_tokens = {
3033 3034 3035 3036 3037 3038 3039
	{ 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" 	},
3040
	{ SRP_OPT_IO_CLASS,		"io_class=%x"		},
3041
	{ SRP_OPT_INITIATOR_EXT,	"initiator_ext=%s"	},
3042
	{ SRP_OPT_CMD_SG_ENTRIES,	"cmd_sg_entries=%u"	},
3043 3044
	{ SRP_OPT_ALLOW_EXT_SG,		"allow_ext_sg=%u"	},
	{ SRP_OPT_SG_TABLESIZE,		"sg_tablesize=%u"	},
3045
	{ SRP_OPT_COMP_VECTOR,		"comp_vector=%u"	},
3046
	{ SRP_OPT_TL_RETRY_COUNT,	"tl_retry_count=%u"	},
3047
	{ SRP_OPT_QUEUE_SIZE,		"queue_size=%d"		},
3048
	{ SRP_OPT_ERR,			NULL 			}
3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066
};

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;
3067
	while ((p = strsep(&sep_opt, ",\n")) != NULL) {
3068 3069 3070 3071 3072 3073 3074 3075 3076
		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);
3077 3078 3079 3080
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3081 3082 3083 3084 3085 3086
			target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

		case SRP_OPT_IOC_GUID:
			p = match_strdup(args);
3087 3088 3089 3090
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3091 3092 3093 3094 3095 3096
			target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

		case SRP_OPT_DGID:
			p = match_strdup(args);
3097 3098 3099 3100
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3101
			if (strlen(p) != 32) {
3102
				pr_warn("bad dest GID parameter '%s'\n", p);
3103
				kfree(p);
3104 3105 3106 3107
				goto out;
			}

			for (i = 0; i < 16; ++i) {
3108 3109 3110 3111 3112 3113 3114
				strlcpy(dgid, p + i * 2, sizeof(dgid));
				if (sscanf(dgid, "%hhx",
					   &target->orig_dgid.raw[i]) < 1) {
					ret = -EINVAL;
					kfree(p);
					goto out;
				}
3115
			}
3116
			kfree(p);
3117 3118 3119 3120
			break;

		case SRP_OPT_PKEY:
			if (match_hex(args, &token)) {
3121
				pr_warn("bad P_Key parameter '%s'\n", p);
3122 3123
				goto out;
			}
3124
			target->pkey = cpu_to_be16(token);
3125 3126 3127 3128
			break;

		case SRP_OPT_SERVICE_ID:
			p = match_strdup(args);
3129 3130 3131 3132
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3133 3134 3135 3136 3137 3138
			target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

		case SRP_OPT_MAX_SECT:
			if (match_int(args, &token)) {
3139
				pr_warn("bad max sect parameter '%s'\n", p);
3140 3141 3142 3143 3144
				goto out;
			}
			target->scsi_host->max_sectors = token;
			break;

3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156
		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;

3157
		case SRP_OPT_MAX_CMD_PER_LUN:
3158
			if (match_int(args, &token) || token < 1) {
3159 3160
				pr_warn("bad max cmd_per_lun parameter '%s'\n",
					p);
3161 3162
				goto out;
			}
3163
			target->scsi_host->cmd_per_lun = token;
3164 3165
			break;

3166 3167
		case SRP_OPT_IO_CLASS:
			if (match_hex(args, &token)) {
3168
				pr_warn("bad IO class parameter '%s'\n", p);
3169 3170 3171 3172
				goto out;
			}
			if (token != SRP_REV10_IB_IO_CLASS &&
			    token != SRP_REV16A_IB_IO_CLASS) {
3173 3174 3175
				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);
3176 3177 3178 3179 3180
				goto out;
			}
			target->io_class = token;
			break;

3181 3182
		case SRP_OPT_INITIATOR_EXT:
			p = match_strdup(args);
3183 3184 3185 3186
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3187 3188 3189 3190
			target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
			kfree(p);
			break;

3191 3192
		case SRP_OPT_CMD_SG_ENTRIES:
			if (match_int(args, &token) || token < 1 || token > 255) {
3193 3194
				pr_warn("bad max cmd_sg_entries parameter '%s'\n",
					p);
3195 3196 3197 3198 3199
				goto out;
			}
			target->cmd_sg_cnt = token;
			break;

3200 3201
		case SRP_OPT_ALLOW_EXT_SG:
			if (match_int(args, &token)) {
3202
				pr_warn("bad allow_ext_sg parameter '%s'\n", p);
3203 3204 3205 3206 3207 3208 3209
				goto out;
			}
			target->allow_ext_sg = !!token;
			break;

		case SRP_OPT_SG_TABLESIZE:
			if (match_int(args, &token) || token < 1 ||
3210
					token > SG_MAX_SEGMENTS) {
3211 3212
				pr_warn("bad max sg_tablesize parameter '%s'\n",
					p);
3213 3214 3215 3216 3217
				goto out;
			}
			target->sg_tablesize = token;
			break;

3218 3219 3220 3221 3222 3223 3224 3225
		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;

3226 3227 3228 3229 3230 3231 3232 3233 3234
		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;

3235
		default:
3236 3237
			pr_warn("unknown parameter or missing value '%s' in target creation request\n",
				p);
3238 3239 3240 3241 3242 3243 3244 3245 3246 3247
			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))
3248 3249
				pr_warn("target creation request is missing parameter '%s'\n",
					srp_opt_tokens[i].pattern);
3250

3251 3252 3253 3254 3255 3256
	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);

3257 3258 3259 3260 3261
out:
	kfree(options);
	return ret;
}

3262 3263
static ssize_t srp_create_target(struct device *dev,
				 struct device_attribute *attr,
3264 3265 3266
				 const char *buf, size_t count)
{
	struct srp_host *host =
3267
		container_of(dev, struct srp_host, dev);
3268 3269
	struct Scsi_Host *target_host;
	struct srp_target_port *target;
3270
	struct srp_rdma_ch *ch;
3271 3272
	struct srp_device *srp_dev = host->srp_dev;
	struct ib_device *ibdev = srp_dev->dev;
B
Bart Van Assche 已提交
3273
	int ret, node_idx, node, cpu, i;
3274
	unsigned int max_sectors_per_mr, mr_per_cmd = 0;
B
Bart Van Assche 已提交
3275
	bool multich = false;
3276 3277 3278 3279 3280 3281

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

3282
	target_host->transportt  = ib_srp_transport_template;
3283 3284
	target_host->max_channel = 0;
	target_host->max_id      = 1;
B
Bart Van Assche 已提交
3285
	target_host->max_lun     = -1LL;
A
Arne Redlich 已提交
3286
	target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
R
Roland Dreier 已提交
3287

3288 3289
	target = host_to_target(target_host);

3290 3291 3292
	target->io_class	= SRP_REV16A_IB_IO_CLASS;
	target->scsi_host	= target_host;
	target->srp_host	= host;
3293
	target->pd		= host->srp_dev->pd;
J
Jason Gunthorpe 已提交
3294
	target->lkey		= host->srp_dev->pd->local_dma_lkey;
3295
	target->cmd_sg_cnt	= cmd_sg_entries;
3296 3297
	target->sg_tablesize	= indirect_sg_entries ? : cmd_sg_entries;
	target->allow_ext_sg	= allow_ext_sg;
3298
	target->tl_retry_count	= 7;
3299
	target->queue_size	= SRP_DEFAULT_QUEUE_SIZE;
3300

3301 3302 3303 3304 3305 3306
	/*
	 * Avoid that the SCSI host can be removed by srp_remove_target()
	 * before this function returns.
	 */
	scsi_host_get(target->scsi_host);

3307 3308 3309
	ret = mutex_lock_interruptible(&host->add_target_mutex);
	if (ret < 0)
		goto put;
3310

3311 3312
	ret = srp_parse_options(buf, target);
	if (ret)
3313
		goto out;
3314

3315 3316
	target->req_ring_size = target->queue_size - SRP_TSK_MGMT_SQ_SIZE;

3317 3318 3319 3320 3321 3322 3323
	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;
3324
		goto out;
3325 3326
	}

3327
	if (!srp_dev->has_fmr && !srp_dev->has_fr && !target->allow_ext_sg &&
3328
	    target->cmd_sg_cnt < target->sg_tablesize) {
3329
		pr_warn("No MR pool and no external indirect descriptors, limiting sg_tablesize to cmd_sg_cnt\n");
3330 3331 3332
		target->sg_tablesize = target->cmd_sg_cnt;
	}

3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356
	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);
	}

3357
	target_host->sg_tablesize = target->sg_tablesize;
3358 3359
	target->mr_pool_size = target->scsi_host->can_queue * mr_per_cmd;
	target->mr_per_cmd = mr_per_cmd;
3360 3361
	target->indirect_size = target->sg_tablesize *
				sizeof (struct srp_direct_buf);
3362 3363 3364 3365
	target->max_iu_len = sizeof (struct srp_cmd) +
			     sizeof (struct srp_indirect_buf) +
			     target->cmd_sg_cnt * sizeof (struct srp_direct_buf);

3366
	INIT_WORK(&target->tl_err_work, srp_tl_err_work);
3367
	INIT_WORK(&target->remove_work, srp_remove_work);
3368
	spin_lock_init(&target->lock);
3369
	ret = ib_query_gid(ibdev, host->port, 0, &target->sgid, NULL);
3370
	if (ret)
3371
		goto out;
3372

B
Bart Van Assche 已提交
3373 3374 3375 3376 3377 3378 3379 3380 3381
	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)
3382
		goto out;
3383

B
Bart Van Assche 已提交
3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411
	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;
3412

B
Bart Van Assche 已提交
3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432
			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,
					     PFX "Connection %d/%d failed\n",
					     ch_start + cpu_idx,
					     target->ch_count);
				if (node_idx == 0 && cpu_idx == 0) {
					goto err_disconnect;
				} else {
					srp_free_ch_ib(target, ch);
					srp_free_req_data(target, ch);
					target->ch_count = ch - target->ch;
3433
					goto connected;
B
Bart Van Assche 已提交
3434 3435 3436 3437 3438 3439 3440
				}
			}

			multich = true;
			cpu_idx++;
		}
		node_idx++;
3441 3442
	}

3443
connected:
B
Bart Van Assche 已提交
3444 3445
	target->scsi_host->nr_hw_queues = target->ch_count;

3446 3447 3448 3449
	ret = srp_add_target(host, target);
	if (ret)
		goto err_disconnect;

3450 3451 3452 3453 3454
	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),
3455
			     be16_to_cpu(target->pkey),
3456
			     be64_to_cpu(target->service_id),
3457
			     target->sgid.raw, target->orig_dgid.raw);
3458
	}
B
Bart Van Assche 已提交
3459

3460 3461 3462 3463
	ret = count;

out:
	mutex_unlock(&host->add_target_mutex);
3464

3465
put:
3466
	scsi_host_put(target->scsi_host);
3467 3468
	if (ret < 0)
		scsi_host_put(target->scsi_host);
3469

3470
	return ret;
3471 3472 3473 3474

err_disconnect:
	srp_disconnect_target(target);

B
Bart Van Assche 已提交
3475 3476 3477 3478 3479
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		srp_free_ch_ib(target, ch);
		srp_free_req_data(target, ch);
	}
3480

B
Bart Van Assche 已提交
3481
	kfree(target->ch);
3482
	goto out;
3483 3484
}

3485
static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
3486

3487 3488
static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
			  char *buf)
3489
{
3490
	struct srp_host *host = container_of(dev, struct srp_host, dev);
3491

3492
	return sprintf(buf, "%s\n", host->srp_dev->dev->name);
3493 3494
}

3495
static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
3496

3497 3498
static ssize_t show_port(struct device *dev, struct device_attribute *attr,
			 char *buf)
3499
{
3500
	struct srp_host *host = container_of(dev, struct srp_host, dev);
3501 3502 3503 3504

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

3505
static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
3506

3507
static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
3508 3509 3510 3511 3512 3513 3514 3515
{
	struct srp_host *host;

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

	INIT_LIST_HEAD(&host->target_list);
3516
	spin_lock_init(&host->target_lock);
3517
	init_completion(&host->released);
3518
	mutex_init(&host->add_target_mutex);
3519
	host->srp_dev = device;
3520 3521
	host->port = port;

3522 3523
	host->dev.class = &srp_class;
	host->dev.parent = device->dev->dma_device;
3524
	dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
3525

3526
	if (device_register(&host->dev))
3527
		goto free_host;
3528
	if (device_create_file(&host->dev, &dev_attr_add_target))
3529
		goto err_class;
3530
	if (device_create_file(&host->dev, &dev_attr_ibdev))
3531
		goto err_class;
3532
	if (device_create_file(&host->dev, &dev_attr_port))
3533 3534 3535 3536 3537
		goto err_class;

	return host;

err_class:
3538
	device_unregister(&host->dev);
3539

3540
free_host:
3541 3542 3543 3544 3545 3546 3547
	kfree(host);

	return NULL;
}

static void srp_add_one(struct ib_device *device)
{
3548
	struct srp_device *srp_dev;
3549
	struct ib_device_attr *attr = &device->attrs;
3550
	struct srp_host *host;
3551
	int mr_page_shift, p;
3552
	u64 max_pages_per_mr;
3553
	unsigned int flags = 0;
3554

3555
	srp_dev = kzalloc(sizeof(*srp_dev), GFP_KERNEL);
3556
	if (!srp_dev)
3557
		return;
3558 3559 3560

	/*
	 * Use the smallest page size supported by the HCA, down to a
3561 3562
	 * minimum of 4096 bytes. We're unlikely to build large sglists
	 * out of smaller entries.
3563
	 */
3564
	mr_page_shift		= max(12, ffs(attr->page_size_cap) - 1);
3565 3566
	srp_dev->mr_page_size	= 1 << mr_page_shift;
	srp_dev->mr_page_mask	= ~((u64) srp_dev->mr_page_size - 1);
3567
	max_pages_per_mr	= attr->max_mr_size;
3568
	do_div(max_pages_per_mr, srp_dev->mr_page_size);
3569
	pr_debug("%s: %llu / %u = %llu <> %u\n", __func__,
3570
		 attr->max_mr_size, srp_dev->mr_page_size,
3571
		 max_pages_per_mr, SRP_MAX_PAGES_PER_MR);
3572 3573
	srp_dev->max_pages_per_mr = min_t(u64, SRP_MAX_PAGES_PER_MR,
					  max_pages_per_mr);
3574 3575 3576

	srp_dev->has_fmr = (device->alloc_fmr && device->dealloc_fmr &&
			    device->map_phys_fmr && device->unmap_fmr);
3577
	srp_dev->has_fr = (attr->device_cap_flags &
3578
			   IB_DEVICE_MEM_MGT_EXTENSIONS);
3579
	if (!never_register && !srp_dev->has_fmr && !srp_dev->has_fr) {
3580
		dev_warn(&device->dev, "neither FMR nor FR is supported\n");
3581
	} else if (!never_register &&
3582
		   attr->max_mr_size >= 2 * srp_dev->mr_page_size) {
3583 3584 3585 3586
		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;
	}
3587

3588 3589 3590 3591
	if (never_register || !register_always ||
	    (!srp_dev->has_fmr && !srp_dev->has_fr))
		flags |= IB_PD_UNSAFE_GLOBAL_RKEY;

3592 3593 3594
	if (srp_dev->use_fast_reg) {
		srp_dev->max_pages_per_mr =
			min_t(u32, srp_dev->max_pages_per_mr,
3595
			      attr->max_fast_reg_page_list_len);
3596
	}
3597 3598
	srp_dev->mr_max_size	= srp_dev->mr_page_size *
				   srp_dev->max_pages_per_mr;
3599
	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",
3600 3601
		 device->name, mr_page_shift, attr->max_mr_size,
		 attr->max_fast_reg_page_list_len,
3602
		 srp_dev->max_pages_per_mr, srp_dev->mr_max_size);
3603 3604 3605 3606

	INIT_LIST_HEAD(&srp_dev->dev_list);

	srp_dev->dev = device;
3607
	srp_dev->pd  = ib_alloc_pd(device, flags);
3608 3609 3610 3611
	if (IS_ERR(srp_dev->pd))
		goto free_dev;


3612
	for (p = rdma_start_port(device); p <= rdma_end_port(device); ++p) {
3613
		host = srp_add_port(srp_dev, p);
3614
		if (host)
3615
			list_add_tail(&host->list, &srp_dev->dev_list);
3616 3617
	}

3618
	ib_set_client_data(device, &srp_client, srp_dev);
3619
	return;
3620 3621 3622

free_dev:
	kfree(srp_dev);
3623 3624
}

3625
static void srp_remove_one(struct ib_device *device, void *client_data)
3626
{
3627
	struct srp_device *srp_dev;
3628
	struct srp_host *host, *tmp_host;
3629
	struct srp_target_port *target;
3630

3631
	srp_dev = client_data;
3632 3633
	if (!srp_dev)
		return;
3634

3635
	list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
3636
		device_unregister(&host->dev);
3637 3638 3639 3640 3641 3642 3643
		/*
		 * Wait for the sysfs entry to go away, so that no new
		 * target ports can be created.
		 */
		wait_for_completion(&host->released);

		/*
3644
		 * Remove all target ports.
3645
		 */
3646
		spin_lock(&host->target_lock);
3647 3648
		list_for_each_entry(target, &host->target_list, list)
			srp_queue_remove_work(target);
3649
		spin_unlock(&host->target_lock);
3650 3651

		/*
3652
		 * Wait for tl_err and target port removal tasks.
3653
		 */
3654
		flush_workqueue(system_long_wq);
3655
		flush_workqueue(srp_remove_wq);
3656 3657 3658 3659

		kfree(host);
	}

3660 3661 3662
	ib_dealloc_pd(srp_dev->pd);

	kfree(srp_dev);
3663 3664
}

3665
static struct srp_function_template ib_srp_transport_functions = {
3666 3667
	.has_rport_state	 = true,
	.reset_timer_if_blocked	 = true,
3668
	.reconnect_delay	 = &srp_reconnect_delay,
3669 3670 3671
	.fast_io_fail_tmo	 = &srp_fast_io_fail_tmo,
	.dev_loss_tmo		 = &srp_dev_loss_tmo,
	.reconnect		 = srp_rport_reconnect,
3672
	.rport_delete		 = srp_rport_delete,
3673
	.terminate_rport_io	 = srp_terminate_io,
3674 3675
};

3676 3677 3678 3679
static int __init srp_init_module(void)
{
	int ret;

3680
	if (srp_sg_tablesize) {
3681
		pr_warn("srp_sg_tablesize is deprecated, please use cmd_sg_entries\n");
3682 3683 3684 3685 3686 3687 3688 3689
		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) {
3690
		pr_warn("Clamping cmd_sg_entries to 255\n");
3691
		cmd_sg_entries = 255;
3692 3693
	}

3694 3695 3696
	if (!indirect_sg_entries)
		indirect_sg_entries = cmd_sg_entries;
	else if (indirect_sg_entries < cmd_sg_entries) {
3697 3698
		pr_warn("Bumping up indirect_sg_entries to match cmd_sg_entries (%u)\n",
			cmd_sg_entries);
3699 3700 3701
		indirect_sg_entries = cmd_sg_entries;
	}

3702 3703 3704 3705 3706 3707
	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;
	}

3708
	srp_remove_wq = create_workqueue("srp_remove");
3709 3710
	if (!srp_remove_wq) {
		ret = -ENOMEM;
3711 3712 3713 3714
		goto out;
	}

	ret = -ENOMEM;
3715 3716 3717
	ib_srp_transport_template =
		srp_attach_transport(&ib_srp_transport_functions);
	if (!ib_srp_transport_template)
3718
		goto destroy_wq;
3719

3720 3721
	ret = class_register(&srp_class);
	if (ret) {
3722
		pr_err("couldn't register class infiniband_srp\n");
3723
		goto release_tr;
3724 3725
	}

3726 3727
	ib_sa_register_client(&srp_sa_client);

3728 3729
	ret = ib_register_client(&srp_client);
	if (ret) {
3730
		pr_err("couldn't register IB client\n");
3731
		goto unreg_sa;
3732 3733
	}

3734 3735 3736 3737 3738 3739 3740 3741 3742 3743 3744 3745 3746
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;
3747 3748 3749 3750 3751
}

static void __exit srp_cleanup_module(void)
{
	ib_unregister_client(&srp_client);
3752
	ib_sa_unregister_client(&srp_sa_client);
3753
	class_unregister(&srp_class);
3754
	srp_release_transport(ib_srp_transport_template);
3755
	destroy_workqueue(srp_remove_wq);
3756 3757 3758 3759
}

module_init(srp_init_module);
module_exit(srp_cleanup_module);