ib_srp.c 110.8 KB
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/*
 * Copyright (c) 2005 Cisco Systems.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/string.h>
#include <linux/parser.h>
#include <linux/random.h>
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#include <linux/jiffies.h>
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#include <linux/lockdep.h>
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#include <linux/inet.h>
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#include <rdma/ib_cache.h>
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#include <linux/atomic.h>
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#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_dbg.h>
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#include <scsi/scsi_tcq.h>
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#include <scsi/srp.h>
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#include <scsi/scsi_transport_srp.h>
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#include "ib_srp.h"

#define DRV_NAME	"ib_srp"
#define PFX		DRV_NAME ": "
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#define DRV_VERSION	"2.0"
#define DRV_RELDATE	"July 26, 2015"
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MODULE_AUTHOR("Roland Dreier");
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MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator");
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MODULE_LICENSE("Dual BSD/GPL");
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MODULE_INFO(release_date, DRV_RELDATE);
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#if !defined(CONFIG_DYNAMIC_DEBUG)
#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt)
#define DYNAMIC_DEBUG_BRANCH(descriptor) false
#endif

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static unsigned int srp_sg_tablesize;
static unsigned int cmd_sg_entries;
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static unsigned int indirect_sg_entries;
static bool allow_ext_sg;
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static bool prefer_fr = true;
static bool register_always = true;
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static bool never_register;
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static int topspin_workarounds = 1;
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module_param(srp_sg_tablesize, uint, 0444);
MODULE_PARM_DESC(srp_sg_tablesize, "Deprecated name for cmd_sg_entries");
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module_param(cmd_sg_entries, uint, 0444);
MODULE_PARM_DESC(cmd_sg_entries,
		 "Default number of gather/scatter entries in the SRP command (default is 12, max 255)");
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module_param(indirect_sg_entries, uint, 0444);
MODULE_PARM_DESC(indirect_sg_entries,
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		 "Default max number of gather/scatter entries (default is 12, max is " __stringify(SG_MAX_SEGMENTS) ")");
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module_param(allow_ext_sg, bool, 0444);
MODULE_PARM_DESC(allow_ext_sg,
		  "Default behavior when there are more than cmd_sg_entries S/G entries after mapping; fails the request when false (default false)");

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

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

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

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module_param(never_register, bool, 0444);
MODULE_PARM_DESC(never_register, "Never register memory");

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

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

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

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

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static void srp_add_one(struct ib_device *device);
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static void srp_remove_one(struct ib_device *device, void *client_data);
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static void srp_recv_done(struct ib_cq *cq, struct ib_wc *wc);
static void srp_handle_qp_err(struct ib_cq *cq, struct ib_wc *wc,
		const char *opname);
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static int srp_ib_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
static int srp_rdma_cm_handler(struct rdma_cm_id *cm_id,
			       struct rdma_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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}

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static int srp_init_ib_qp(struct srp_target_port *target,
			  struct ib_qp *qp)
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{
	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,
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				  be16_to_cpu(target->ib_cm.pkey),
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				  &attr->pkey_index);
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	if (ret)
		goto out;

	attr->qp_state        = IB_QPS_INIT;
	attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
				    IB_ACCESS_REMOTE_WRITE);
	attr->port_num        = target->srp_host->port;

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

out:
	kfree(attr);
	return ret;
}

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static int srp_new_ib_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_ib_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->ib_cm.cm_id)
		ib_destroy_cm_id(ch->ib_cm.cm_id);
	ch->ib_cm.cm_id = new_cm_id;
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	if (rdma_cap_opa_ah(target->srp_host->srp_dev->dev,
			    target->srp_host->port))
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		ch->ib_cm.path.rec_type = SA_PATH_REC_TYPE_OPA;
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	else
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		ch->ib_cm.path.rec_type = SA_PATH_REC_TYPE_IB;
	ch->ib_cm.path.sgid = target->sgid;
	ch->ib_cm.path.dgid = target->ib_cm.orig_dgid;
	ch->ib_cm.path.pkey = target->ib_cm.pkey;
	ch->ib_cm.path.service_id = target->ib_cm.service_id;
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	return 0;
}

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static const char *inet_ntop(const void *sa, char *dst, unsigned int size)
{
	switch (((struct sockaddr *)sa)->sa_family) {
	case AF_INET:
		snprintf(dst, size, "%pI4",
			 &((struct sockaddr_in *)sa)->sin_addr);
		break;
	case AF_INET6:
		snprintf(dst, size, "%pI6",
			 &((struct sockaddr_in6 *)sa)->sin6_addr);
		break;
	default:
		snprintf(dst, size, "???");
		break;
	}
	return dst;
}

static int srp_new_rdma_cm_id(struct srp_rdma_ch *ch)
{
	struct srp_target_port *target = ch->target;
	struct rdma_cm_id *new_cm_id;
	char src_addr[64], dst_addr[64];
	int ret;

	new_cm_id = rdma_create_id(target->net, srp_rdma_cm_handler, ch,
				   RDMA_PS_TCP, IB_QPT_RC);
	if (IS_ERR(new_cm_id)) {
		ret = PTR_ERR(new_cm_id);
		new_cm_id = NULL;
		goto out;
	}

	init_completion(&ch->done);
	ret = rdma_resolve_addr(new_cm_id, target->rdma_cm.src_specified ?
				(struct sockaddr *)&target->rdma_cm.src : NULL,
				(struct sockaddr *)&target->rdma_cm.dst,
				SRP_PATH_REC_TIMEOUT_MS);
	if (ret) {
		pr_err("No route available from %s to %s (%d)\n",
		       target->rdma_cm.src_specified ?
		       inet_ntop(&target->rdma_cm.src, src_addr,
				 sizeof(src_addr)) : "(any)",
		       inet_ntop(&target->rdma_cm.dst, dst_addr,
				 sizeof(dst_addr)),
		       ret);
		goto out;
	}
	ret = wait_for_completion_interruptible(&ch->done);
	if (ret < 0)
		goto out;

	ret = ch->status;
	if (ret) {
		pr_err("Resolving address %s failed (%d)\n",
		       inet_ntop(&target->rdma_cm.dst, dst_addr,
				 sizeof(dst_addr)),
		       ret);
		goto out;
	}

	swap(ch->rdma_cm.cm_id, new_cm_id);

out:
	if (new_cm_id)
		rdma_destroy_id(new_cm_id);

	return ret;
}

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

	return target->using_rdma_cm ? srp_new_rdma_cm_id(ch) :
		srp_new_ib_cm_id(ch);
}

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

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

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

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

	if (!pool)
		return;

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

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

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

	for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) {
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		mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG,
				 max_page_list_len);
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		if (IS_ERR(mr)) {
			ret = PTR_ERR(mr);
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			if (ret == -ENOMEM)
				pr_info("%s: ib_alloc_mr() failed. Try to reduce max_cmd_per_lun, max_sect or ch_count\n",
					dev_name(&device->dev));
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			goto destroy_pool;
		}
		d->mr = mr;
		list_add_tail(&d->entry, &pool->free_list);
	}

out:
	return pool;

destroy_pool:
	srp_destroy_fr_pool(pool);

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

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

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

	return d;
}

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

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

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

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

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/**
 * srp_destroy_qp() - destroy an RDMA queue pair
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 * @ch: SRP RDMA channel.
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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 srp_rdma_ch *ch)
555
{
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	spin_lock_irq(&ch->lock);
	ib_process_cq_direct(ch->send_cq, -1);
	spin_unlock_irq(&ch->lock);

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

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static int srp_create_ch_ib(struct srp_rdma_ch *ch)
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{
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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;
596
	init_attr->cap.max_send_wr     = m * target->queue_size;
597
	init_attr->cap.max_recv_wr     = target->queue_size + 1;
598 599
	init_attr->cap.max_recv_sge    = 1;
	init_attr->cap.max_send_sge    = 1;
600
	init_attr->sq_sig_type         = IB_SIGNAL_REQ_WR;
601
	init_attr->qp_type             = IB_QPT_RC;
602 603
	init_attr->send_cq             = send_cq;
	init_attr->recv_cq             = recv_cq;
604

B
Bart Van Assche 已提交
605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620
	if (target->using_rdma_cm) {
		ret = rdma_create_qp(ch->rdma_cm.cm_id, dev->pd, init_attr);
		qp = ch->rdma_cm.cm_id->qp;
	} else {
		qp = ib_create_qp(dev->pd, init_attr);
		if (!IS_ERR(qp)) {
			ret = srp_init_ib_qp(target, qp);
			if (ret)
				ib_destroy_qp(qp);
		} else {
			ret = PTR_ERR(qp);
		}
	}
	if (ret) {
		pr_err("QP creation failed for dev %s: %d\n",
		       dev_name(&dev->dev->dev), ret);
621
		goto err_send_cq;
622 623
	}

624
	if (dev->use_fast_reg) {
625 626 627 628 629 630 631
		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;
		}
632
	} else if (dev->use_fmr) {
633 634 635 636 637 638 639 640 641
		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;
		}
	}

642
	if (ch->qp)
643
		srp_destroy_qp(ch);
644
	if (ch->recv_cq)
C
Christoph Hellwig 已提交
645
		ib_free_cq(ch->recv_cq);
646
	if (ch->send_cq)
C
Christoph Hellwig 已提交
647
		ib_free_cq(ch->send_cq);
648

649 650 651
	ch->qp = qp;
	ch->recv_cq = recv_cq;
	ch->send_cq = send_cq;
652

653 654 655 656 657 658 659 660 661 662
	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;
	}

663 664 665 666
	kfree(init_attr);
	return 0;

err_qp:
B
Bart Van Assche 已提交
667 668 669 670
	if (target->using_rdma_cm)
		rdma_destroy_qp(ch->rdma_cm.cm_id);
	else
		ib_destroy_qp(qp);
671 672

err_send_cq:
C
Christoph Hellwig 已提交
673
	ib_free_cq(send_cq);
674 675

err_recv_cq:
C
Christoph Hellwig 已提交
676
	ib_free_cq(recv_cq);
677 678

err:
679 680 681 682
	kfree(init_attr);
	return ret;
}

683 684
/*
 * Note: this function may be called without srp_alloc_iu_bufs() having been
685
 * invoked. Hence the ch->[rt]x_ring checks.
686
 */
687 688
static void srp_free_ch_ib(struct srp_target_port *target,
			   struct srp_rdma_ch *ch)
689
{
690
	struct srp_device *dev = target->srp_host->srp_dev;
691 692
	int i;

B
Bart Van Assche 已提交
693 694 695
	if (!ch->target)
		return;

B
Bart Van Assche 已提交
696 697 698 699 700 701 702 703 704 705
	if (target->using_rdma_cm) {
		if (ch->rdma_cm.cm_id) {
			rdma_destroy_id(ch->rdma_cm.cm_id);
			ch->rdma_cm.cm_id = NULL;
		}
	} else {
		if (ch->ib_cm.cm_id) {
			ib_destroy_cm_id(ch->ib_cm.cm_id);
			ch->ib_cm.cm_id = NULL;
		}
706 707
	}

B
Bart Van Assche 已提交
708 709 710 711
	/* If srp_new_cm_id() succeeded but srp_create_ch_ib() not, return. */
	if (!ch->qp)
		return;

712
	if (dev->use_fast_reg) {
713 714
		if (ch->fr_pool)
			srp_destroy_fr_pool(ch->fr_pool);
715
	} else if (dev->use_fmr) {
716 717
		if (ch->fmr_pool)
			ib_destroy_fmr_pool(ch->fmr_pool);
718
	}
C
Christoph Hellwig 已提交
719

720
	srp_destroy_qp(ch);
C
Christoph Hellwig 已提交
721 722
	ib_free_cq(ch->send_cq);
	ib_free_cq(ch->recv_cq);
723

B
Bart Van Assche 已提交
724 725 726 727 728 729 730 731
	/*
	 * 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;

732 733
	ch->qp = NULL;
	ch->send_cq = ch->recv_cq = NULL;
734

735
	if (ch->rx_ring) {
736
		for (i = 0; i < target->queue_size; ++i)
737 738 739
			srp_free_iu(target->srp_host, ch->rx_ring[i]);
		kfree(ch->rx_ring);
		ch->rx_ring = NULL;
740
	}
741
	if (ch->tx_ring) {
742
		for (i = 0; i < target->queue_size; ++i)
743 744 745
			srp_free_iu(target->srp_host, ch->tx_ring[i]);
		kfree(ch->tx_ring);
		ch->tx_ring = NULL;
746
	}
747 748 749
}

static void srp_path_rec_completion(int status,
750
				    struct sa_path_rec *pathrec,
751
				    void *ch_ptr)
752
{
753 754
	struct srp_rdma_ch *ch = ch_ptr;
	struct srp_target_port *target = ch->target;
755

756
	ch->status = status;
757
	if (status)
758 759
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "Got failed path rec status %d\n", status);
760
	else
B
Bart Van Assche 已提交
761
		ch->ib_cm.path = *pathrec;
762
	complete(&ch->done);
763 764
}

B
Bart Van Assche 已提交
765
static int srp_ib_lookup_path(struct srp_rdma_ch *ch)
766
{
767
	struct srp_target_port *target = ch->target;
768
	int ret = -ENODEV;
769

B
Bart Van Assche 已提交
770
	ch->ib_cm.path.numb_path = 1;
771 772 773

	init_completion(&ch->done);

774 775 776 777 778 779 780
	/*
	 * Avoid that the SCSI host can be removed by srp_remove_target()
	 * before srp_path_rec_completion() is called.
	 */
	if (!scsi_host_get(target->scsi_host))
		goto out;

B
Bart Van Assche 已提交
781
	ch->ib_cm.path_query_id = ib_sa_path_rec_get(&srp_sa_client,
782 783
					       target->srp_host->srp_dev->dev,
					       target->srp_host->port,
B
Bart Van Assche 已提交
784
					       &ch->ib_cm.path,
785 786 787 788 789 790 791 792
					       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,
B
Bart Van Assche 已提交
793 794
					       ch, &ch->ib_cm.path_query);
	ret = ch->ib_cm.path_query_id;
795 796
	if (ret < 0)
		goto put;
797 798

	ret = wait_for_completion_interruptible(&ch->done);
799
	if (ret < 0)
800
		goto put;
801

802 803
	ret = ch->status;
	if (ret < 0)
804
		shost_printk(KERN_WARNING, target->scsi_host,
805
			     PFX "Path record query failed: sgid %pI6, dgid %pI6, pkey %#04x, service_id %#16llx\n",
B
Bart Van Assche 已提交
806 807 808
			     ch->ib_cm.path.sgid.raw, ch->ib_cm.path.dgid.raw,
			     be16_to_cpu(target->ib_cm.pkey),
			     be64_to_cpu(target->ib_cm.service_id));
809

810 811 812 813 814
put:
	scsi_host_put(target->scsi_host);

out:
	return ret;
815 816
}

B
Bart Van Assche 已提交
817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844
static int srp_rdma_lookup_path(struct srp_rdma_ch *ch)
{
	struct srp_target_port *target = ch->target;
	int ret;

	init_completion(&ch->done);

	ret = rdma_resolve_route(ch->rdma_cm.cm_id, SRP_PATH_REC_TIMEOUT_MS);
	if (ret)
		return ret;

	wait_for_completion_interruptible(&ch->done);

	if (ch->status != 0)
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Path resolution failed\n");

	return ch->status;
}

static int srp_lookup_path(struct srp_rdma_ch *ch)
{
	struct srp_target_port *target = ch->target;

	return target->using_rdma_cm ? srp_rdma_lookup_path(ch) :
		srp_ib_lookup_path(ch);
}

845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861
static u8 srp_get_subnet_timeout(struct srp_host *host)
{
	struct ib_port_attr attr;
	int ret;
	u8 subnet_timeout = 18;

	ret = ib_query_port(host->srp_dev->dev, host->port, &attr);
	if (ret == 0)
		subnet_timeout = attr.subnet_timeout;

	if (unlikely(subnet_timeout < 15))
		pr_warn("%s: subnet timeout %d may cause SRP login to fail.\n",
			dev_name(&host->srp_dev->dev->dev), subnet_timeout);

	return subnet_timeout;
}

B
Bart Van Assche 已提交
862
static int srp_send_req(struct srp_rdma_ch *ch, bool multich)
863
{
864
	struct srp_target_port *target = ch->target;
865
	struct {
B
Bart Van Assche 已提交
866 867 868 869
		struct rdma_conn_param	  rdma_param;
		struct srp_login_req_rdma rdma_req;
		struct ib_cm_req_param	  ib_param;
		struct srp_login_req	  ib_req;
870
	} *req = NULL;
871
	char *ipi, *tpi;
872 873 874 875 876 877
	int status;

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

B
Bart Van Assche 已提交
878 879
	req->ib_param.flow_control = 1;
	req->ib_param.retry_count = target->tl_retry_count;
880 881 882 883 884

	/*
	 * Pick some arbitrary defaults here; we could make these
	 * module parameters if anyone cared about setting them.
	 */
B
Bart Van Assche 已提交
885 886 887 888 889 890 891 892
	req->ib_param.responder_resources = 4;
	req->ib_param.rnr_retry_count = 7;
	req->ib_param.max_cm_retries = 15;

	req->ib_req.opcode = SRP_LOGIN_REQ;
	req->ib_req.tag = 0;
	req->ib_req.req_it_iu_len = cpu_to_be32(target->max_iu_len);
	req->ib_req.req_buf_fmt	= cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
893
					      SRP_BUF_FORMAT_INDIRECT);
B
Bart Van Assche 已提交
894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915
	req->ib_req.req_flags = (multich ? SRP_MULTICHAN_MULTI :
				 SRP_MULTICHAN_SINGLE);

	if (target->using_rdma_cm) {
		req->rdma_param.flow_control = req->ib_param.flow_control;
		req->rdma_param.responder_resources =
			req->ib_param.responder_resources;
		req->rdma_param.initiator_depth = req->ib_param.initiator_depth;
		req->rdma_param.retry_count = req->ib_param.retry_count;
		req->rdma_param.rnr_retry_count = req->ib_param.rnr_retry_count;
		req->rdma_param.private_data = &req->rdma_req;
		req->rdma_param.private_data_len = sizeof(req->rdma_req);

		req->rdma_req.opcode = req->ib_req.opcode;
		req->rdma_req.tag = req->ib_req.tag;
		req->rdma_req.req_it_iu_len = req->ib_req.req_it_iu_len;
		req->rdma_req.req_buf_fmt = req->ib_req.req_buf_fmt;
		req->rdma_req.req_flags	= req->ib_req.req_flags;

		ipi = req->rdma_req.initiator_port_id;
		tpi = req->rdma_req.target_port_id;
	} else {
916 917 918 919
		u8 subnet_timeout;

		subnet_timeout = srp_get_subnet_timeout(target->srp_host);

B
Bart Van Assche 已提交
920 921 922 923 924 925 926 927 928 929 930
		req->ib_param.primary_path = &ch->ib_cm.path;
		req->ib_param.alternate_path = NULL;
		req->ib_param.service_id = target->ib_cm.service_id;
		get_random_bytes(&req->ib_param.starting_psn, 4);
		req->ib_param.starting_psn &= 0xffffff;
		req->ib_param.qp_num = ch->qp->qp_num;
		req->ib_param.qp_type = ch->qp->qp_type;
		req->ib_param.local_cm_response_timeout = subnet_timeout + 2;
		req->ib_param.remote_cm_response_timeout = subnet_timeout + 2;
		req->ib_param.private_data = &req->ib_req;
		req->ib_param.private_data_len = sizeof(req->ib_req);
931

B
Bart Van Assche 已提交
932 933
		ipi = req->ib_req.initiator_port_id;
		tpi = req->ib_req.target_port_id;
934 935
	}

936
	/*
R
Roland Dreier 已提交
937
	 * In the published SRP specification (draft rev. 16a), the
938 939 940 941 942 943 944 945
	 * 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) {
946 947 948 949
		memcpy(ipi,     &target->sgid.global.interface_id, 8);
		memcpy(ipi + 8, &target->initiator_ext, 8);
		memcpy(tpi,     &target->ioc_guid, 8);
		memcpy(tpi + 8, &target->id_ext, 8);
950
	} else {
951 952 953 954
		memcpy(ipi,     &target->initiator_ext, 8);
		memcpy(ipi + 8, &target->sgid.global.interface_id, 8);
		memcpy(tpi,     &target->id_ext, 8);
		memcpy(tpi + 8, &target->ioc_guid, 8);
955 956
	}

957 958
	/*
	 * Topspin/Cisco SRP targets will reject our login unless we
959 960
	 * zero out the first 8 bytes of our initiator port ID and set
	 * the second 8 bytes to the local node GUID.
961
	 */
962
	if (srp_target_is_topspin(target)) {
963 964 965
		shost_printk(KERN_DEBUG, target->scsi_host,
			     PFX "Topspin/Cisco initiator port ID workaround "
			     "activated for target GUID %016llx\n",
966
			     be64_to_cpu(target->ioc_guid));
967 968
		memset(ipi, 0, 8);
		memcpy(ipi + 8, &target->srp_host->srp_dev->dev->node_guid, 8);
969 970
	}

B
Bart Van Assche 已提交
971 972 973 974
	if (target->using_rdma_cm)
		status = rdma_connect(ch->rdma_cm.cm_id, &req->rdma_param);
	else
		status = ib_send_cm_req(ch->ib_cm.cm_id, &req->ib_param);
975 976 977 978 979 980

	kfree(req);

	return status;
}

981 982 983 984 985 986 987 988 989 990 991 992
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)
993
		queue_work(srp_remove_wq, &target->remove_work);
994 995 996 997

	return changed;
}

998 999
static void srp_disconnect_target(struct srp_target_port *target)
{
B
Bart Van Assche 已提交
1000
	struct srp_rdma_ch *ch;
B
Bart Van Assche 已提交
1001
	int i, ret;
1002

1003
	/* XXX should send SRP_I_LOGOUT request */
1004

1005 1006 1007
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		ch->connected = false;
B
Bart Van Assche 已提交
1008 1009 1010 1011 1012 1013 1014 1015 1016 1017
		ret = 0;
		if (target->using_rdma_cm) {
			if (ch->rdma_cm.cm_id)
				rdma_disconnect(ch->rdma_cm.cm_id);
		} else {
			if (ch->ib_cm.cm_id)
				ret = ib_send_cm_dreq(ch->ib_cm.cm_id,
						      NULL, 0);
		}
		if (ret < 0) {
1018 1019
			shost_printk(KERN_DEBUG, target->scsi_host,
				     PFX "Sending CM DREQ failed\n");
1020
		}
1021
	}
1022 1023
}

1024 1025
static void srp_free_req_data(struct srp_target_port *target,
			      struct srp_rdma_ch *ch)
1026
{
1027 1028
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
1029 1030 1031
	struct srp_request *req;
	int i;

1032
	if (!ch->req_ring)
1033 1034 1035
		return;

	for (i = 0; i < target->req_ring_size; ++i) {
1036
		req = &ch->req_ring[i];
1037
		if (dev->use_fast_reg) {
1038
			kfree(req->fr_list);
1039
		} else {
1040
			kfree(req->fmr_list);
1041 1042
			kfree(req->map_page);
		}
1043 1044 1045 1046 1047 1048
		if (req->indirect_dma_addr) {
			ib_dma_unmap_single(ibdev, req->indirect_dma_addr,
					    target->indirect_size,
					    DMA_TO_DEVICE);
		}
		kfree(req->indirect_desc);
1049
	}
1050

1051 1052
	kfree(ch->req_ring);
	ch->req_ring = NULL;
1053 1054
}

1055
static int srp_alloc_req_data(struct srp_rdma_ch *ch)
1056
{
1057
	struct srp_target_port *target = ch->target;
1058 1059 1060
	struct srp_device *srp_dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = srp_dev->dev;
	struct srp_request *req;
1061
	void *mr_list;
1062 1063 1064
	dma_addr_t dma_addr;
	int i, ret = -ENOMEM;

1065 1066 1067
	ch->req_ring = kcalloc(target->req_ring_size, sizeof(*ch->req_ring),
			       GFP_KERNEL);
	if (!ch->req_ring)
1068 1069 1070
		goto out;

	for (i = 0; i < target->req_ring_size; ++i) {
1071
		req = &ch->req_ring[i];
1072
		mr_list = kmalloc(target->mr_per_cmd * sizeof(void *),
1073 1074 1075
				  GFP_KERNEL);
		if (!mr_list)
			goto out;
1076
		if (srp_dev->use_fast_reg) {
1077
			req->fr_list = mr_list;
1078
		} else {
1079
			req->fmr_list = mr_list;
1080 1081 1082 1083 1084
			req->map_page = kmalloc(srp_dev->max_pages_per_mr *
						sizeof(void *), GFP_KERNEL);
			if (!req->map_page)
				goto out;
		}
1085
		req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
1086
		if (!req->indirect_desc)
1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102
			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;
}

1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117
/**
 * 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);
}

1118 1119
static void srp_remove_target(struct srp_target_port *target)
{
B
Bart Van Assche 已提交
1120 1121
	struct srp_rdma_ch *ch;
	int i;
1122

1123 1124
	WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);

1125
	srp_del_scsi_host_attr(target->scsi_host);
1126
	srp_rport_get(target->rport);
1127 1128
	srp_remove_host(target->scsi_host);
	scsi_remove_host(target->scsi_host);
1129
	srp_stop_rport_timers(target->rport);
1130
	srp_disconnect_target(target);
B
Bart Van Assche 已提交
1131
	kobj_ns_drop(KOBJ_NS_TYPE_NET, target->net);
B
Bart Van Assche 已提交
1132 1133 1134 1135
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		srp_free_ch_ib(target, ch);
	}
1136
	cancel_work_sync(&target->tl_err_work);
1137
	srp_rport_put(target->rport);
B
Bart Van Assche 已提交
1138 1139 1140 1141 1142 1143
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		srp_free_req_data(target, ch);
	}
	kfree(target->ch);
	target->ch = NULL;
1144 1145 1146 1147 1148

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

1149 1150 1151
	scsi_host_put(target->scsi_host);
}

D
David Howells 已提交
1152
static void srp_remove_work(struct work_struct *work)
1153
{
D
David Howells 已提交
1154
	struct srp_target_port *target =
1155
		container_of(work, struct srp_target_port, remove_work);
1156

1157
	WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
1158

1159
	srp_remove_target(target);
1160 1161
}

1162 1163 1164 1165 1166 1167 1168
static void srp_rport_delete(struct srp_rport *rport)
{
	struct srp_target_port *target = rport->lld_data;

	srp_queue_remove_work(target);
}

1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182
/**
 * 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
1183
static int srp_connect_ch(struct srp_rdma_ch *ch, bool multich)
1184
{
1185
	struct srp_target_port *target = ch->target;
1186 1187
	int ret;

1188
	WARN_ON_ONCE(!multich && srp_connected_ch(target) > 0);
1189

1190
	ret = srp_lookup_path(ch);
1191
	if (ret)
B
Bart Van Assche 已提交
1192
		goto out;
1193 1194

	while (1) {
1195
		init_completion(&ch->done);
B
Bart Van Assche 已提交
1196
		ret = srp_send_req(ch, multich);
1197
		if (ret)
B
Bart Van Assche 已提交
1198
			goto out;
1199
		ret = wait_for_completion_interruptible(&ch->done);
1200
		if (ret < 0)
B
Bart Van Assche 已提交
1201
			goto out;
1202 1203 1204 1205 1206 1207 1208

		/*
		 * 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
1209 1210
		ret = ch->status;
		switch (ret) {
1211
		case 0:
1212
			ch->connected = true;
B
Bart Van Assche 已提交
1213
			goto out;
1214 1215

		case SRP_PORT_REDIRECT:
1216
			ret = srp_lookup_path(ch);
1217
			if (ret)
B
Bart Van Assche 已提交
1218
				goto out;
1219 1220 1221 1222 1223
			break;

		case SRP_DLID_REDIRECT:
			break;

D
David Dillow 已提交
1224 1225
		case SRP_STALE_CONN:
			shost_printk(KERN_ERR, target->scsi_host, PFX
1226
				     "giving up on stale connection\n");
B
Bart Van Assche 已提交
1227 1228
			ret = -ECONNRESET;
			goto out;
D
David Dillow 已提交
1229

1230
		default:
B
Bart Van Assche 已提交
1231
			goto out;
1232 1233
		}
	}
B
Bart Van Assche 已提交
1234 1235 1236

out:
	return ret <= 0 ? ret : -ENODEV;
1237 1238
}

C
Christoph Hellwig 已提交
1239 1240 1241 1242 1243 1244 1245
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)
1246 1247 1248 1249 1250 1251 1252 1253 1254 1255
{
	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
1256 1257
	wr.wr_cqe = &req->reg_cqe;
	req->reg_cqe.done = srp_inv_rkey_err_done;
1258
	return ib_post_send(ch->qp, &wr, &bad_wr);
1259 1260
}

1261
static void srp_unmap_data(struct scsi_cmnd *scmnd,
1262
			   struct srp_rdma_ch *ch,
1263 1264
			   struct srp_request *req)
{
1265
	struct srp_target_port *target = ch->target;
1266 1267 1268
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_device *ibdev = dev->dev;
	int i, res;
1269

1270
	if (!scsi_sglist(scmnd) ||
1271 1272 1273 1274
	    (scmnd->sc_data_direction != DMA_TO_DEVICE &&
	     scmnd->sc_data_direction != DMA_FROM_DEVICE))
		return;

1275 1276 1277 1278
	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
1279
			res = srp_inv_rkey(req, ch, (*pfr)->mr->rkey);
1280 1281 1282 1283 1284 1285 1286 1287 1288
			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)
1289
			srp_fr_pool_put(ch->fr_pool, req->fr_list,
1290
					req->nmdesc);
1291
	} else if (dev->use_fmr) {
1292 1293 1294 1295 1296
		struct ib_pool_fmr **pfmr;

		for (i = req->nmdesc, pfmr = req->fmr_list; i > 0; i--, pfmr++)
			ib_fmr_pool_unmap(*pfmr);
	}
1297

1298 1299
	ib_dma_unmap_sg(ibdev, scsi_sglist(scmnd), scsi_sg_count(scmnd),
			scmnd->sc_data_direction);
1300 1301
}

B
Bart Van Assche 已提交
1302 1303
/**
 * srp_claim_req - Take ownership of the scmnd associated with a request.
1304
 * @ch: SRP RDMA channel.
B
Bart Van Assche 已提交
1305
 * @req: SRP request.
1306
 * @sdev: If not NULL, only take ownership for this SCSI device.
B
Bart Van Assche 已提交
1307 1308 1309 1310 1311 1312
 * @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.
 */
1313
static struct scsi_cmnd *srp_claim_req(struct srp_rdma_ch *ch,
B
Bart Van Assche 已提交
1314
				       struct srp_request *req,
1315
				       struct scsi_device *sdev,
B
Bart Van Assche 已提交
1316 1317 1318 1319
				       struct scsi_cmnd *scmnd)
{
	unsigned long flags;

1320
	spin_lock_irqsave(&ch->lock, flags);
1321 1322 1323
	if (req->scmnd &&
	    (!sdev || req->scmnd->device == sdev) &&
	    (!scmnd || req->scmnd == scmnd)) {
B
Bart Van Assche 已提交
1324 1325 1326 1327 1328
		scmnd = req->scmnd;
		req->scmnd = NULL;
	} else {
		scmnd = NULL;
	}
1329
	spin_unlock_irqrestore(&ch->lock, flags);
B
Bart Van Assche 已提交
1330 1331 1332 1333 1334

	return scmnd;
}

/**
B
Bart Van Assche 已提交
1335
 * srp_free_req() - Unmap data and adjust ch->req_lim.
1336
 * @ch:     SRP RDMA channel.
1337 1338 1339
 * @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
1340
 */
1341 1342
static void srp_free_req(struct srp_rdma_ch *ch, struct srp_request *req,
			 struct scsi_cmnd *scmnd, s32 req_lim_delta)
1343
{
1344 1345
	unsigned long flags;

1346
	srp_unmap_data(scmnd, ch, req);
B
Bart Van Assche 已提交
1347

1348 1349 1350
	spin_lock_irqsave(&ch->lock, flags);
	ch->req_lim += req_lim_delta;
	spin_unlock_irqrestore(&ch->lock, flags);
1351 1352
}

1353 1354
static void srp_finish_req(struct srp_rdma_ch *ch, struct srp_request *req,
			   struct scsi_device *sdev, int result)
1355
{
1356
	struct scsi_cmnd *scmnd = srp_claim_req(ch, req, sdev, NULL);
B
Bart Van Assche 已提交
1357 1358

	if (scmnd) {
1359
		srp_free_req(ch, req, scmnd, 0);
1360
		scmnd->result = result;
B
Bart Van Assche 已提交
1361 1362
		scmnd->scsi_done(scmnd);
	}
1363 1364
}

1365
static void srp_terminate_io(struct srp_rport *rport)
1366
{
1367
	struct srp_target_port *target = rport->lld_data;
B
Bart Van Assche 已提交
1368
	struct srp_rdma_ch *ch;
1369 1370
	struct Scsi_Host *shost = target->scsi_host;
	struct scsi_device *sdev;
B
Bart Van Assche 已提交
1371
	int i, j;
1372

1373 1374 1375 1376 1377 1378 1379
	/*
	 * 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
1380 1381
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
1382

B
Bart Van Assche 已提交
1383 1384 1385 1386 1387 1388
		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);
		}
1389 1390
	}
}
1391

1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403
/*
 * 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
1404 1405 1406
	struct srp_rdma_ch *ch;
	int i, j, ret = 0;
	bool multich = false;
1407

1408
	srp_disconnect_target(target);
1409 1410 1411 1412

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

1413
	/*
1414 1415 1416
	 * 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.
1417
	 */
B
Bart Van Assche 已提交
1418 1419 1420
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		ret += srp_new_cm_id(ch);
1421
	}
B
Bart Van Assche 已提交
1422 1423 1424 1425
	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];
1426

B
Bart Van Assche 已提交
1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437
			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);
1438

B
Bart Van Assche 已提交
1439 1440 1441 1442
		INIT_LIST_HEAD(&ch->free_tx);
		for (j = 0; j < target->queue_size; ++j)
			list_add(&ch->tx_ring[j]->list, &ch->free_tx);
	}
1443 1444 1445

	target->qp_in_error = false;

B
Bart Van Assche 已提交
1446 1447
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
1448
		if (ret)
B
Bart Van Assche 已提交
1449 1450 1451 1452
			break;
		ret = srp_connect_ch(ch, multich);
		multich = true;
	}
1453

1454 1455 1456
	if (ret == 0)
		shost_printk(KERN_INFO, target->scsi_host,
			     PFX "reconnect succeeded\n");
1457 1458 1459 1460

	return ret;
}

1461 1462
static void srp_map_desc(struct srp_map_state *state, dma_addr_t dma_addr,
			 unsigned int dma_len, u32 rkey)
1463
{
1464
	struct srp_direct_buf *desc = state->desc;
1465

1466 1467
	WARN_ON_ONCE(!dma_len);

1468 1469 1470
	desc->va = cpu_to_be64(dma_addr);
	desc->key = cpu_to_be32(rkey);
	desc->len = cpu_to_be32(dma_len);
1471

1472 1473 1474 1475
	state->total_len += dma_len;
	state->desc++;
	state->ndesc++;
}
1476

1477
static int srp_map_finish_fmr(struct srp_map_state *state,
1478
			      struct srp_rdma_ch *ch)
1479
{
1480 1481
	struct srp_target_port *target = ch->target;
	struct srp_device *dev = target->srp_host->srp_dev;
1482 1483
	struct ib_pool_fmr *fmr;
	u64 io_addr = 0;
1484

1485 1486 1487 1488
	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);
1489
		return -ENOMEM;
1490
	}
1491

S
Sagi Grimberg 已提交
1492 1493 1494 1495 1496
	WARN_ON_ONCE(!dev->use_fmr);

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

B
Bart Van Assche 已提交
1497
	if (state->npages == 1 && target->global_rkey) {
S
Sagi Grimberg 已提交
1498
		srp_map_desc(state, state->base_dma_addr, state->dma_len,
B
Bart Van Assche 已提交
1499
			     target->global_rkey);
S
Sagi Grimberg 已提交
1500 1501 1502
		goto reset_state;
	}

1503
	fmr = ib_fmr_pool_map_phys(ch->fmr_pool, state->pages,
1504 1505 1506
				   state->npages, io_addr);
	if (IS_ERR(fmr))
		return PTR_ERR(fmr);
1507

1508
	*state->fmr.next++ = fmr;
1509
	state->nmdesc++;
1510

1511 1512
	srp_map_desc(state, state->base_dma_addr & ~dev->mr_page_mask,
		     state->dma_len, fmr->fmr->rkey);
1513

S
Sagi Grimberg 已提交
1514 1515 1516 1517
reset_state:
	state->npages = 0;
	state->dma_len = 0;

1518 1519 1520
	return 0;
}

C
Christoph Hellwig 已提交
1521 1522 1523 1524 1525
static void srp_reg_mr_err_done(struct ib_cq *cq, struct ib_wc *wc)
{
	srp_handle_qp_err(cq, wc, "FAST REG");
}

1526 1527 1528 1529 1530 1531
/*
 * 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.
 */
1532
static int srp_map_finish_fr(struct srp_map_state *state,
C
Christoph Hellwig 已提交
1533
			     struct srp_request *req,
1534 1535
			     struct srp_rdma_ch *ch, int sg_nents,
			     unsigned int *sg_offset_p)
1536
{
1537
	struct srp_target_port *target = ch->target;
1538 1539
	struct srp_device *dev = target->srp_host->srp_dev;
	struct ib_send_wr *bad_wr;
1540
	struct ib_reg_wr wr;
1541 1542
	struct srp_fr_desc *desc;
	u32 rkey;
1543
	int n, err;
1544

1545 1546 1547 1548
	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);
1549
		return -ENOMEM;
1550
	}
1551

S
Sagi Grimberg 已提交
1552 1553
	WARN_ON_ONCE(!dev->use_fast_reg);

B
Bart Van Assche 已提交
1554
	if (sg_nents == 1 && target->global_rkey) {
1555 1556 1557 1558
		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,
B
Bart Van Assche 已提交
1559
			     target->global_rkey);
1560 1561
		if (sg_offset_p)
			*sg_offset_p = 0;
1562
		return 1;
S
Sagi Grimberg 已提交
1563 1564
	}

1565
	desc = srp_fr_pool_get(ch->fr_pool);
1566 1567 1568 1569 1570 1571
	if (!desc)
		return -ENOMEM;

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

1572 1573
	n = ib_map_mr_sg(desc->mr, state->sg, sg_nents, sg_offset_p,
			 dev->mr_page_size);
1574 1575
	if (unlikely(n < 0)) {
		srp_fr_pool_put(ch->fr_pool, &desc, 1);
1576
		pr_debug("%s: ib_map_mr_sg(%d, %d) returned %d.\n",
1577
			 dev_name(&req->scmnd->device->sdev_gendev), sg_nents,
1578
			 sg_offset_p ? *sg_offset_p : -1, n);
1579
		return n;
1580
	}
1581

1582
	WARN_ON_ONCE(desc->mr->length == 0);
1583

C
Christoph Hellwig 已提交
1584 1585
	req->reg_cqe.done = srp_reg_mr_err_done;

1586 1587
	wr.wr.next = NULL;
	wr.wr.opcode = IB_WR_REG_MR;
C
Christoph Hellwig 已提交
1588
	wr.wr.wr_cqe = &req->reg_cqe;
1589 1590 1591 1592 1593 1594 1595
	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);
1596

1597
	*state->fr.next++ = desc;
1598 1599
	state->nmdesc++;

1600 1601
	srp_map_desc(state, desc->mr->iova,
		     desc->mr->length, desc->mr->rkey);
1602

S
Sagi Grimberg 已提交
1603
	err = ib_post_send(ch->qp, &wr.wr, &bad_wr);
1604 1605
	if (unlikely(err)) {
		WARN_ON_ONCE(err == -ENOMEM);
S
Sagi Grimberg 已提交
1606
		return err;
1607
	}
S
Sagi Grimberg 已提交
1608

1609
	return n;
1610 1611
}

1612
static int srp_map_sg_entry(struct srp_map_state *state,
1613
			    struct srp_rdma_ch *ch,
1614
			    struct scatterlist *sg)
1615
{
1616
	struct srp_target_port *target = ch->target;
1617 1618 1619 1620
	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);
1621
	unsigned int len = 0;
1622 1623
	int ret;

1624
	WARN_ON_ONCE(!dma_len);
1625

1626
	while (dma_len) {
1627
		unsigned offset = dma_addr & ~dev->mr_page_mask;
1628 1629 1630

		if (state->npages == dev->max_pages_per_mr ||
		    (state->npages > 0 && offset != 0)) {
1631
			ret = srp_map_finish_fmr(state, ch);
1632 1633 1634 1635
			if (ret)
				return ret;
		}

1636
		len = min_t(unsigned int, dma_len, dev->mr_page_size - offset);
1637

1638 1639
		if (!state->npages)
			state->base_dma_addr = dma_addr;
1640
		state->pages[state->npages++] = dma_addr & dev->mr_page_mask;
1641
		state->dma_len += len;
1642 1643 1644 1645
		dma_addr += len;
		dma_len -= len;
	}

1646
	/*
1647
	 * If the end of the MR is not on a page boundary then we need to
1648
	 * close it out and start a new one -- we can only merge at page
1649
	 * boundaries.
1650 1651
	 */
	ret = 0;
1652
	if ((dma_addr & ~dev->mr_page_mask) != 0)
1653
		ret = srp_map_finish_fmr(state, ch);
1654 1655 1656
	return ret;
}

S
Sagi Grimberg 已提交
1657 1658 1659
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)
1660 1661
{
	struct scatterlist *sg;
1662
	int i, ret;
1663

S
Sagi Grimberg 已提交
1664 1665
	state->pages = req->map_page;
	state->fmr.next = req->fmr_list;
1666
	state->fmr.end = req->fmr_list + ch->target->mr_per_cmd;
S
Sagi Grimberg 已提交
1667 1668

	for_each_sg(scat, sg, count, i) {
1669
		ret = srp_map_sg_entry(state, ch, sg);
S
Sagi Grimberg 已提交
1670 1671
		if (ret)
			return ret;
1672
	}
1673

1674
	ret = srp_map_finish_fmr(state, ch);
S
Sagi Grimberg 已提交
1675 1676 1677 1678 1679 1680 1681 1682 1683 1684
	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)
{
1685 1686
	unsigned int sg_offset = 0;

1687
	state->fr.next = req->fr_list;
1688
	state->fr.end = req->fr_list + ch->target->mr_per_cmd;
1689
	state->sg = scat;
S
Sagi Grimberg 已提交
1690

1691 1692 1693
	if (count == 0)
		return 0;

B
Bart Van Assche 已提交
1694
	while (count) {
1695
		int i, n;
S
Sagi Grimberg 已提交
1696

1697
		n = srp_map_finish_fr(state, req, ch, count, &sg_offset);
1698 1699 1700
		if (unlikely(n < 0))
			return n;

B
Bart Van Assche 已提交
1701
		count -= n;
1702 1703 1704
		for (i = 0; i < n; i++)
			state->sg = sg_next(state->sg);
	}
S
Sagi Grimberg 已提交
1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720

	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),
B
Bart Van Assche 已提交
1721
			     target->global_rkey);
1722
	}
1723

S
Sagi Grimberg 已提交
1724
	return 0;
1725 1726
}

1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742
/*
 * 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];
1743
	struct scatterlist idb_sg[1];
1744 1745 1746 1747 1748 1749 1750 1751 1752
	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;
1753 1754 1755

	if (dev->use_fast_reg) {
		state.sg = idb_sg;
1756
		sg_init_one(idb_sg, req->indirect_desc, idb_len);
1757
		idb_sg->dma_address = req->indirect_dma_addr; /* hack! */
1758 1759 1760
#ifdef CONFIG_NEED_SG_DMA_LENGTH
		idb_sg->dma_length = idb_sg->length;	      /* hack^2 */
#endif
1761
		ret = srp_map_finish_fr(&state, req, ch, 1, NULL);
1762 1763
		if (ret < 0)
			return ret;
1764
		WARN_ON_ONCE(ret < 1);
1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775
	} 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;
	}
1776 1777 1778

	*idb_rkey = idb_desc.key;

1779
	return 0;
1780 1781
}

1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805
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);
}

1806 1807 1808 1809 1810 1811 1812 1813 1814
/**
 * 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.
 */
1815
static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_rdma_ch *ch,
1816 1817
			struct srp_request *req)
{
1818
	struct srp_target_port *target = ch->target;
1819
	struct scatterlist *scat;
1820
	struct srp_cmd *cmd = req->cmd->buf;
1821
	int len, nents, count, ret;
1822 1823
	struct srp_device *dev;
	struct ib_device *ibdev;
1824 1825
	struct srp_map_state state;
	struct srp_indirect_buf *indirect_hdr;
1826 1827
	u32 idb_len, table_len;
	__be32 idb_rkey;
1828
	u8 fmt;
1829

1830
	if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
1831 1832 1833 1834
		return sizeof (struct srp_cmd);

	if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
	    scmnd->sc_data_direction != DMA_TO_DEVICE) {
1835 1836 1837
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled data direction %d\n",
			     scmnd->sc_data_direction);
1838 1839 1840
		return -EINVAL;
	}

1841 1842
	nents = scsi_sg_count(scmnd);
	scat  = scsi_sglist(scmnd);
1843

1844
	dev = target->srp_host->srp_dev;
1845 1846 1847
	ibdev = dev->dev;

	count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
1848 1849
	if (unlikely(count == 0))
		return -EIO;
1850 1851 1852

	fmt = SRP_DATA_DESC_DIRECT;
	len = sizeof (struct srp_cmd) +	sizeof (struct srp_direct_buf);
1853

B
Bart Van Assche 已提交
1854
	if (count == 1 && target->global_rkey) {
1855 1856 1857 1858 1859 1860
		/*
		 * 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.
		 */
1861
		struct srp_direct_buf *buf = (void *) cmd->add_data;
1862

1863
		buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
B
Bart Van Assche 已提交
1864
		buf->key = cpu_to_be32(target->global_rkey);
1865
		buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
1866

1867
		req->nmdesc = 0;
1868 1869 1870
		goto map_complete;
	}

1871 1872 1873
	/*
	 * We have more than one scatter/gather entry, so build our indirect
	 * descriptor table, trying to merge as many entries as we can.
1874 1875 1876
	 */
	indirect_hdr = (void *) cmd->add_data;

1877 1878 1879
	ib_dma_sync_single_for_cpu(ibdev, req->indirect_dma_addr,
				   target->indirect_size, DMA_TO_DEVICE);

1880
	memset(&state, 0, sizeof(state));
B
Bart Van Assche 已提交
1881
	state.desc = req->indirect_desc;
S
Sagi Grimberg 已提交
1882
	if (dev->use_fast_reg)
1883
		ret = srp_map_sg_fr(&state, ch, req, scat, count);
S
Sagi Grimberg 已提交
1884
	else if (dev->use_fmr)
1885
		ret = srp_map_sg_fmr(&state, ch, req, scat, count);
S
Sagi Grimberg 已提交
1886
	else
1887 1888 1889 1890
		ret = srp_map_sg_dma(&state, ch, req, scat, count);
	req->nmdesc = state.nmdesc;
	if (ret < 0)
		goto unmap;
1891

1892 1893 1894
	{
		DEFINE_DYNAMIC_DEBUG_METADATA(ddm,
			"Memory mapping consistency check");
1895
		if (DYNAMIC_DEBUG_BRANCH(ddm))
1896 1897
			srp_check_mapping(&state, ch, req, scat, count);
	}
1898

1899 1900 1901 1902 1903
	/* 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.
1904 1905
	 */
	if (state.ndesc == 1) {
1906 1907
		/*
		 * Memory registration collapsed the sg-list into one entry,
1908 1909 1910
		 * so use a direct descriptor.
		 */
		struct srp_direct_buf *buf = (void *) cmd->add_data;
1911

1912
		*buf = req->indirect_desc[0];
1913
		goto map_complete;
1914 1915
	}

1916 1917 1918 1919
	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");
1920 1921
		ret = -EIO;
		goto unmap;
1922 1923 1924
	}

	count = min(state.ndesc, target->cmd_sg_cnt);
1925
	table_len = state.ndesc * sizeof (struct srp_direct_buf);
1926
	idb_len = sizeof(struct srp_indirect_buf) + table_len;
1927 1928 1929

	fmt = SRP_DATA_DESC_INDIRECT;
	len = sizeof(struct srp_cmd) + sizeof (struct srp_indirect_buf);
1930
	len += count * sizeof (struct srp_direct_buf);
1931

1932 1933
	memcpy(indirect_hdr->desc_list, req->indirect_desc,
	       count * sizeof (struct srp_direct_buf));
1934

B
Bart Van Assche 已提交
1935
	if (!target->global_rkey) {
1936 1937 1938
		ret = srp_map_idb(ch, req, state.gen.next, state.gen.end,
				  idb_len, &idb_rkey);
		if (ret < 0)
1939
			goto unmap;
1940 1941
		req->nmdesc++;
	} else {
B
Bart Van Assche 已提交
1942
		idb_rkey = cpu_to_be32(target->global_rkey);
1943 1944
	}

1945
	indirect_hdr->table_desc.va = cpu_to_be64(req->indirect_dma_addr);
1946
	indirect_hdr->table_desc.key = idb_rkey;
1947 1948 1949 1950
	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)
1951
		cmd->data_out_desc_cnt = count;
1952
	else
1953 1954 1955 1956
		cmd->data_in_desc_cnt = count;

	ib_dma_sync_single_for_device(ibdev, req->indirect_dma_addr, table_len,
				      DMA_TO_DEVICE);
1957 1958

map_complete:
1959 1960 1961 1962 1963 1964
	if (scmnd->sc_data_direction == DMA_TO_DEVICE)
		cmd->buf_fmt = fmt << 4;
	else
		cmd->buf_fmt = fmt;

	return len;
1965 1966 1967

unmap:
	srp_unmap_data(scmnd, ch, req);
1968 1969
	if (ret == -ENOMEM && req->nmdesc >= target->mr_pool_size)
		ret = -E2BIG;
1970
	return ret;
1971 1972
}

1973 1974 1975
/*
 * Return an IU and possible credit to the free pool
 */
1976
static void srp_put_tx_iu(struct srp_rdma_ch *ch, struct srp_iu *iu,
1977 1978 1979 1980
			  enum srp_iu_type iu_type)
{
	unsigned long flags;

1981 1982
	spin_lock_irqsave(&ch->lock, flags);
	list_add(&iu->list, &ch->free_tx);
1983
	if (iu_type != SRP_IU_RSP)
1984 1985
		++ch->req_lim;
	spin_unlock_irqrestore(&ch->lock, flags);
1986 1987
}

1988
/*
1989
 * Must be called with ch->lock held to protect req_lim and free_tx.
1990
 * If IU is not sent, it must be returned using srp_put_tx_iu().
1991 1992 1993 1994 1995 1996 1997 1998 1999 2000
 *
 * 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.
 */
2001
static struct srp_iu *__srp_get_tx_iu(struct srp_rdma_ch *ch,
2002 2003
				      enum srp_iu_type iu_type)
{
2004
	struct srp_target_port *target = ch->target;
2005 2006 2007
	s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
	struct srp_iu *iu;

2008 2009
	lockdep_assert_held(&ch->lock);

C
Christoph Hellwig 已提交
2010
	ib_process_cq_direct(ch->send_cq, -1);
2011

2012
	if (list_empty(&ch->free_tx))
2013 2014 2015
		return NULL;

	/* Initiator responses to target requests do not consume credits */
2016
	if (iu_type != SRP_IU_RSP) {
2017
		if (ch->req_lim <= rsv) {
2018 2019 2020 2021
			++target->zero_req_lim;
			return NULL;
		}

2022
		--ch->req_lim;
2023 2024
	}

2025
	iu = list_first_entry(&ch->free_tx, struct srp_iu, list);
2026
	list_del(&iu->list);
2027 2028 2029
	return iu;
}

2030 2031 2032 2033 2034
/*
 * Note: if this function is called from inside ib_drain_sq() then it will
 * be called without ch->lock being held. If ib_drain_sq() dequeues a WQE
 * with status IB_WC_SUCCESS then that's a bug.
 */
C
Christoph Hellwig 已提交
2035 2036 2037 2038 2039 2040 2041 2042 2043 2044
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;
	}

2045 2046
	lockdep_assert_held(&ch->lock);

C
Christoph Hellwig 已提交
2047 2048 2049
	list_add(&iu->list, &ch->free_tx);
}

2050
static int srp_post_send(struct srp_rdma_ch *ch, struct srp_iu *iu, int len)
2051
{
2052
	struct srp_target_port *target = ch->target;
2053 2054 2055 2056 2057
	struct ib_sge list;
	struct ib_send_wr wr, *bad_wr;

	list.addr   = iu->dma;
	list.length = len;
2058
	list.lkey   = target->lkey;
2059

C
Christoph Hellwig 已提交
2060 2061
	iu->cqe.done = srp_send_done;

2062
	wr.next       = NULL;
C
Christoph Hellwig 已提交
2063
	wr.wr_cqe     = &iu->cqe;
2064 2065 2066 2067 2068
	wr.sg_list    = &list;
	wr.num_sge    = 1;
	wr.opcode     = IB_WR_SEND;
	wr.send_flags = IB_SEND_SIGNALED;

2069
	return ib_post_send(ch->qp, &wr, &bad_wr);
2070 2071
}

2072
static int srp_post_recv(struct srp_rdma_ch *ch, struct srp_iu *iu)
2073
{
2074
	struct srp_target_port *target = ch->target;
2075
	struct ib_recv_wr wr, *bad_wr;
2076
	struct ib_sge list;
2077 2078 2079

	list.addr   = iu->dma;
	list.length = iu->size;
2080
	list.lkey   = target->lkey;
2081

C
Christoph Hellwig 已提交
2082 2083
	iu->cqe.done = srp_recv_done;

2084
	wr.next     = NULL;
C
Christoph Hellwig 已提交
2085
	wr.wr_cqe   = &iu->cqe;
2086 2087 2088
	wr.sg_list  = &list;
	wr.num_sge  = 1;

2089
	return ib_post_recv(ch->qp, &wr, &bad_wr);
2090 2091
}

2092
static void srp_process_rsp(struct srp_rdma_ch *ch, struct srp_rsp *rsp)
2093
{
2094
	struct srp_target_port *target = ch->target;
2095 2096 2097 2098 2099
	struct srp_request *req;
	struct scsi_cmnd *scmnd;
	unsigned long flags;

	if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
2100 2101
		spin_lock_irqsave(&ch->lock, flags);
		ch->req_lim += be32_to_cpu(rsp->req_lim_delta);
2102 2103 2104 2105 2106 2107 2108 2109 2110 2111
		if (rsp->tag == ch->tsk_mgmt_tag) {
			ch->tsk_mgmt_status = -1;
			if (be32_to_cpu(rsp->resp_data_len) >= 4)
				ch->tsk_mgmt_status = rsp->data[3];
			complete(&ch->tsk_mgmt_done);
		} else {
			shost_printk(KERN_ERR, target->scsi_host,
				     "Received tsk mgmt response too late for tag %#llx\n",
				     rsp->tag);
		}
2112
		spin_unlock_irqrestore(&ch->lock, flags);
2113
	} else {
B
Bart Van Assche 已提交
2114
		scmnd = scsi_host_find_tag(target->scsi_host, rsp->tag);
2115
		if (scmnd && scmnd->host_scribble) {
B
Bart Van Assche 已提交
2116 2117
			req = (void *)scmnd->host_scribble;
			scmnd = srp_claim_req(ch, req, NULL, scmnd);
2118 2119
		} else {
			scmnd = NULL;
B
Bart Van Assche 已提交
2120
		}
B
Bart Van Assche 已提交
2121
		if (!scmnd) {
2122
			shost_printk(KERN_ERR, target->scsi_host,
B
Bart Van Assche 已提交
2123 2124
				     "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
2125

2126 2127 2128
			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
2129 2130 2131

			return;
		}
2132 2133 2134 2135 2136 2137 2138 2139 2140
		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
2141
		if (unlikely(rsp->flags & SRP_RSP_FLAG_DIUNDER))
2142
			scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
B
Bart Van Assche 已提交
2143 2144 2145 2146 2147 2148
		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));
2149

2150
		srp_free_req(ch, req, scmnd,
B
Bart Van Assche 已提交
2151 2152
			     be32_to_cpu(rsp->req_lim_delta));

2153 2154
		scmnd->host_scribble = NULL;
		scmnd->scsi_done(scmnd);
2155 2156 2157
	}
}

2158
static int srp_response_common(struct srp_rdma_ch *ch, s32 req_delta,
2159 2160
			       void *rsp, int len)
{
2161
	struct srp_target_port *target = ch->target;
2162
	struct ib_device *dev = target->srp_host->srp_dev->dev;
2163 2164
	unsigned long flags;
	struct srp_iu *iu;
2165
	int err;
2166

2167 2168 2169 2170
	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);
2171

2172 2173 2174
	if (!iu) {
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "no IU available to send response\n");
2175
		return 1;
2176 2177 2178 2179 2180 2181
	}

	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);

2182
	err = srp_post_send(ch, iu, len);
2183
	if (err) {
2184 2185
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "unable to post response: %d\n", err);
2186
		srp_put_tx_iu(ch, iu, SRP_IU_RSP);
2187
	}
2188 2189 2190 2191

	return err;
}

2192
static void srp_process_cred_req(struct srp_rdma_ch *ch,
2193 2194 2195 2196 2197 2198 2199 2200
				 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);

2201 2202
	if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
		shost_printk(KERN_ERR, ch->target->scsi_host, PFX
2203 2204 2205
			     "problems processing SRP_CRED_REQ\n");
}

2206
static void srp_process_aer_req(struct srp_rdma_ch *ch,
2207 2208
				struct srp_aer_req *req)
{
2209
	struct srp_target_port *target = ch->target;
2210 2211 2212 2213 2214 2215 2216
	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
2217
		     "ignoring AER for LUN %llu\n", scsilun_to_int(&req->lun));
2218

2219
	if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
2220 2221 2222 2223
		shost_printk(KERN_ERR, target->scsi_host, PFX
			     "problems processing SRP_AER_REQ\n");
}

C
Christoph Hellwig 已提交
2224
static void srp_recv_done(struct ib_cq *cq, struct ib_wc *wc)
2225
{
C
Christoph Hellwig 已提交
2226 2227
	struct srp_iu *iu = container_of(wc->wr_cqe, struct srp_iu, cqe);
	struct srp_rdma_ch *ch = cq->cq_context;
2228
	struct srp_target_port *target = ch->target;
2229
	struct ib_device *dev = target->srp_host->srp_dev->dev;
2230
	int res;
2231 2232
	u8 opcode;

C
Christoph Hellwig 已提交
2233 2234 2235 2236 2237
	if (unlikely(wc->status != IB_WC_SUCCESS)) {
		srp_handle_qp_err(cq, wc, "RECV");
		return;
	}

2238
	ib_dma_sync_single_for_cpu(dev, iu->dma, ch->max_ti_iu_len,
2239
				   DMA_FROM_DEVICE);
2240 2241 2242 2243

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

	if (0) {
2244 2245
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "recv completion, opcode 0x%02x\n", opcode);
B
Bart Van Assche 已提交
2246 2247
		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
			       iu->buf, wc->byte_len, true);
2248 2249 2250 2251
	}

	switch (opcode) {
	case SRP_RSP:
2252
		srp_process_rsp(ch, iu->buf);
2253 2254
		break;

2255
	case SRP_CRED_REQ:
2256
		srp_process_cred_req(ch, iu->buf);
2257 2258 2259
		break;

	case SRP_AER_REQ:
2260
		srp_process_aer_req(ch, iu->buf);
2261 2262
		break;

2263 2264
	case SRP_T_LOGOUT:
		/* XXX Handle target logout */
2265 2266
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Got target logout request\n");
2267 2268 2269
		break;

	default:
2270 2271
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled SRP opcode 0x%02x\n", opcode);
2272 2273 2274
		break;
	}

2275
	ib_dma_sync_single_for_device(dev, iu->dma, ch->max_ti_iu_len,
2276
				      DMA_FROM_DEVICE);
2277

2278
	res = srp_post_recv(ch, iu);
2279 2280 2281
	if (res != 0)
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "Recv failed with error code %d\n", res);
2282 2283
}

2284 2285
/**
 * srp_tl_err_work() - handle a transport layer error
2286
 * @work: Work structure embedded in an SRP target port.
2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299
 *
 * 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
2300 2301
static void srp_handle_qp_err(struct ib_cq *cq, struct ib_wc *wc,
		const char *opname)
2302
{
C
Christoph Hellwig 已提交
2303
	struct srp_rdma_ch *ch = cq->cq_context;
2304 2305
	struct srp_target_port *target = ch->target;

2306
	if (ch->connected && !target->qp_in_error) {
C
Christoph Hellwig 已提交
2307 2308 2309 2310
		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);
2311
		queue_work(system_long_wq, &target->tl_err_work);
2312
	}
2313 2314 2315
	target->qp_in_error = true;
}

2316
static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
2317
{
2318
	struct srp_target_port *target = host_to_target(shost);
2319
	struct srp_rport *rport = target->rport;
2320
	struct srp_rdma_ch *ch;
2321 2322 2323
	struct srp_request *req;
	struct srp_iu *iu;
	struct srp_cmd *cmd;
2324
	struct ib_device *dev;
2325
	unsigned long flags;
B
Bart Van Assche 已提交
2326 2327
	u32 tag;
	u16 idx;
2328
	int len, ret;
2329 2330 2331 2332 2333 2334 2335 2336 2337 2338
	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);
2339

2340 2341 2342
	scmnd->result = srp_chkready(target->rport);
	if (unlikely(scmnd->result))
		goto err;
2343

B
Bart Van Assche 已提交
2344 2345
	WARN_ON_ONCE(scmnd->request->tag < 0);
	tag = blk_mq_unique_tag(scmnd->request);
B
Bart Van Assche 已提交
2346
	ch = &target->ch[blk_mq_unique_tag_to_hwq(tag)];
B
Bart Van Assche 已提交
2347 2348 2349 2350
	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);
2351 2352 2353 2354

	spin_lock_irqsave(&ch->lock, flags);
	iu = __srp_get_tx_iu(ch, SRP_IU_CMD);
	spin_unlock_irqrestore(&ch->lock, flags);
2355

B
Bart Van Assche 已提交
2356 2357 2358 2359
	if (!iu)
		goto err;

	req = &ch->req_ring[idx];
2360
	dev = target->srp_host->srp_dev->dev;
2361
	ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len,
2362
				   DMA_TO_DEVICE);
2363

2364
	scmnd->host_scribble = (void *) req;
2365 2366 2367 2368 2369

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

	cmd->opcode = SRP_CMD;
B
Bart Van Assche 已提交
2370
	int_to_scsilun(scmnd->device->lun, &cmd->lun);
B
Bart Van Assche 已提交
2371
	cmd->tag    = tag;
2372 2373 2374 2375 2376
	memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);

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

2377
	len = srp_map_data(scmnd, ch, req);
2378
	if (len < 0) {
2379
		shost_printk(KERN_ERR, target->scsi_host,
2380 2381 2382 2383
			     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
2384
		 * max_pages_per_mr sg-list elements, tell the SCSI mid-layer
2385 2386 2387 2388
		 * to reduce queue depth temporarily.
		 */
		scmnd->result = len == -ENOMEM ?
			DID_OK << 16 | QUEUE_FULL << 1 : DID_ERROR << 16;
2389
		goto err_iu;
2390 2391
	}

2392
	ib_dma_sync_single_for_device(dev, iu->dma, target->max_iu_len,
2393
				      DMA_TO_DEVICE);
2394

2395
	if (srp_post_send(ch, iu, len)) {
2396
		shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
2397 2398 2399
		goto err_unmap;
	}

2400 2401
	ret = 0;

2402 2403 2404 2405
unlock_rport:
	if (in_scsi_eh)
		mutex_unlock(&rport->mutex);

2406
	return ret;
2407 2408

err_unmap:
2409
	srp_unmap_data(scmnd, ch, req);
2410

2411
err_iu:
2412
	srp_put_tx_iu(ch, iu, SRP_IU_CMD);
2413

2414 2415 2416 2417 2418 2419
	/*
	 * Avoid that the loops that iterate over the request ring can
	 * encounter a dangling SCSI command pointer.
	 */
	req->scmnd = NULL;

2420 2421 2422 2423 2424 2425 2426
err:
	if (scmnd->result) {
		scmnd->scsi_done(scmnd);
		ret = 0;
	} else {
		ret = SCSI_MLQUEUE_HOST_BUSY;
	}
2427

2428
	goto unlock_rport;
2429 2430
}

2431 2432
/*
 * Note: the resources allocated in this function are freed in
2433
 * srp_free_ch_ib().
2434
 */
2435
static int srp_alloc_iu_bufs(struct srp_rdma_ch *ch)
2436
{
2437
	struct srp_target_port *target = ch->target;
2438 2439
	int i;

2440 2441 2442
	ch->rx_ring = kcalloc(target->queue_size, sizeof(*ch->rx_ring),
			      GFP_KERNEL);
	if (!ch->rx_ring)
2443
		goto err_no_ring;
2444 2445 2446
	ch->tx_ring = kcalloc(target->queue_size, sizeof(*ch->tx_ring),
			      GFP_KERNEL);
	if (!ch->tx_ring)
2447 2448 2449
		goto err_no_ring;

	for (i = 0; i < target->queue_size; ++i) {
2450 2451 2452 2453
		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])
2454 2455 2456
			goto err;
	}

2457
	for (i = 0; i < target->queue_size; ++i) {
2458 2459 2460 2461
		ch->tx_ring[i] = srp_alloc_iu(target->srp_host,
					      target->max_iu_len,
					      GFP_KERNEL, DMA_TO_DEVICE);
		if (!ch->tx_ring[i])
2462
			goto err;
2463

2464
		list_add(&ch->tx_ring[i]->list, &ch->free_tx);
2465 2466 2467 2468 2469
	}

	return 0;

err:
2470
	for (i = 0; i < target->queue_size; ++i) {
2471 2472
		srp_free_iu(target->srp_host, ch->rx_ring[i]);
		srp_free_iu(target->srp_host, ch->tx_ring[i]);
2473 2474
	}

2475 2476

err_no_ring:
2477 2478 2479 2480
	kfree(ch->tx_ring);
	ch->tx_ring = NULL;
	kfree(ch->rx_ring);
	ch->rx_ring = NULL;
2481

2482 2483 2484
	return -ENOMEM;
}

2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511
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;
}

2512
static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
2513
			       const struct srp_login_rsp *lrsp,
2514
			       struct srp_rdma_ch *ch)
2515
{
2516
	struct srp_target_port *target = ch->target;
2517 2518
	struct ib_qp_attr *qp_attr = NULL;
	int attr_mask = 0;
B
Bart Van Assche 已提交
2519
	int ret = 0;
2520 2521 2522
	int i;

	if (lrsp->opcode == SRP_LOGIN_RSP) {
2523 2524
		ch->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len);
		ch->req_lim       = be32_to_cpu(lrsp->req_lim_delta);
2525 2526 2527 2528 2529 2530

		/*
		 * Reserve credits for task management so we don't
		 * bounce requests back to the SCSI mid-layer.
		 */
		target->scsi_host->can_queue
2531
			= min(ch->req_lim - SRP_TSK_MGMT_SQ_SIZE,
2532
			      target->scsi_host->can_queue);
2533 2534 2535
		target->scsi_host->cmd_per_lun
			= min_t(int, target->scsi_host->can_queue,
				target->scsi_host->cmd_per_lun);
2536 2537 2538 2539 2540 2541 2542
	} else {
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);
		ret = -ECONNRESET;
		goto error;
	}

2543 2544
	if (!ch->rx_ring) {
		ret = srp_alloc_iu_bufs(ch);
2545 2546 2547 2548
		if (ret)
			goto error;
	}

2549
	for (i = 0; i < target->queue_size; i++) {
2550 2551 2552
		struct srp_iu *iu = ch->rx_ring[i];

		ret = srp_post_recv(ch, iu);
2553
		if (ret)
B
Bart Van Assche 已提交
2554
			goto error;
2555 2556
	}

B
Bart Van Assche 已提交
2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570
	if (!target->using_rdma_cm) {
		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;

		ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
		if (ret)
			goto error_free;
2571

B
Bart Van Assche 已提交
2572 2573 2574 2575
		qp_attr->qp_state = IB_QPS_RTS;
		ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
		if (ret)
			goto error_free;
2576

B
Bart Van Assche 已提交
2577
		target->rq_tmo_jiffies = srp_compute_rq_tmo(qp_attr, attr_mask);
2578

B
Bart Van Assche 已提交
2579 2580 2581 2582 2583 2584
		ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
		if (ret)
			goto error_free;

		ret = ib_send_cm_rtu(cm_id, NULL, 0);
	}
2585 2586 2587 2588 2589

error_free:
	kfree(qp_attr);

error:
2590
	ch->status = ret;
2591 2592
}

B
Bart Van Assche 已提交
2593 2594 2595
static void srp_ib_cm_rej_handler(struct ib_cm_id *cm_id,
				  struct ib_cm_event *event,
				  struct srp_rdma_ch *ch)
2596
{
2597
	struct srp_target_port *target = ch->target;
2598
	struct Scsi_Host *shost = target->scsi_host;
2599 2600
	struct ib_class_port_info *cpi;
	int opcode;
B
Bart Van Assche 已提交
2601
	u16 dlid;
2602 2603 2604 2605

	switch (event->param.rej_rcvd.reason) {
	case IB_CM_REJ_PORT_CM_REDIRECT:
		cpi = event->param.rej_rcvd.ari;
B
Bart Van Assche 已提交
2606 2607 2608
		dlid = be16_to_cpu(cpi->redirect_lid);
		sa_path_set_dlid(&ch->ib_cm.path, dlid);
		ch->ib_cm.path.pkey = cpi->redirect_pkey;
2609
		cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
B
Bart Van Assche 已提交
2610
		memcpy(ch->ib_cm.path.dgid.raw, cpi->redirect_gid, 16);
2611

B
Bart Van Assche 已提交
2612
		ch->status = dlid ? SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
2613 2614 2615
		break;

	case IB_CM_REJ_PORT_REDIRECT:
2616
		if (srp_target_is_topspin(target)) {
B
Bart Van Assche 已提交
2617 2618
			union ib_gid *dgid = &ch->ib_cm.path.dgid;

2619 2620 2621 2622 2623
			/*
			 * Topspin/Cisco SRP gateways incorrectly send
			 * reject reason code 25 when they mean 24
			 * (port redirect).
			 */
B
Bart Van Assche 已提交
2624
			memcpy(dgid->raw, event->param.rej_rcvd.ari, 16);
2625

2626 2627
			shost_printk(KERN_DEBUG, shost,
				     PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
B
Bart Van Assche 已提交
2628 2629
				     be64_to_cpu(dgid->global.subnet_prefix),
				     be64_to_cpu(dgid->global.interface_id));
2630

2631
			ch->status = SRP_PORT_REDIRECT;
2632
		} else {
2633 2634
			shost_printk(KERN_WARNING, shost,
				     "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
2635
			ch->status = -ECONNRESET;
2636 2637 2638 2639
		}
		break;

	case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
2640 2641
		shost_printk(KERN_WARNING, shost,
			    "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
2642
		ch->status = -ECONNRESET;
2643 2644 2645 2646 2647 2648 2649 2650 2651
		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)
2652 2653
				shost_printk(KERN_WARNING, shost,
					     PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
2654
			else
B
Bart Van Assche 已提交
2655 2656
				shost_printk(KERN_WARNING, shost, PFX
					     "SRP LOGIN from %pI6 to %pI6 REJECTED, reason 0x%08x\n",
2657
					     target->sgid.raw,
B
Bart Van Assche 已提交
2658 2659
					     target->ib_cm.orig_dgid.raw,
					     reason);
2660
		} else
2661 2662 2663
			shost_printk(KERN_WARNING, shost,
				     "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
				     " opcode 0x%02x\n", opcode);
2664
		ch->status = -ECONNRESET;
2665 2666
		break;

D
David Dillow 已提交
2667 2668
	case IB_CM_REJ_STALE_CONN:
		shost_printk(KERN_WARNING, shost, "  REJ reason: stale connection\n");
2669
		ch->status = SRP_STALE_CONN;
D
David Dillow 已提交
2670 2671
		break;

2672
	default:
2673 2674
		shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
			     event->param.rej_rcvd.reason);
2675
		ch->status = -ECONNRESET;
2676 2677 2678
	}
}

B
Bart Van Assche 已提交
2679
static int srp_ib_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
2680
{
2681 2682
	struct srp_rdma_ch *ch = cm_id->context;
	struct srp_target_port *target = ch->target;
2683 2684 2685 2686
	int comp = 0;

	switch (event->event) {
	case IB_CM_REQ_ERROR:
2687 2688
		shost_printk(KERN_DEBUG, target->scsi_host,
			     PFX "Sending CM REQ failed\n");
2689
		comp = 1;
2690
		ch->status = -ECONNRESET;
2691 2692 2693 2694
		break;

	case IB_CM_REP_RECEIVED:
		comp = 1;
2695
		srp_cm_rep_handler(cm_id, event->private_data, ch);
2696 2697 2698
		break;

	case IB_CM_REJ_RECEIVED:
2699
		shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
2700 2701
		comp = 1;

B
Bart Van Assche 已提交
2702
		srp_ib_cm_rej_handler(cm_id, event, ch);
2703 2704
		break;

2705
	case IB_CM_DREQ_RECEIVED:
2706 2707
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "DREQ received - connection closed\n");
2708
		ch->connected = false;
2709
		if (ib_send_cm_drep(cm_id, NULL, 0))
2710 2711
			shost_printk(KERN_ERR, target->scsi_host,
				     PFX "Sending CM DREP failed\n");
2712
		queue_work(system_long_wq, &target->tl_err_work);
2713 2714 2715
		break;

	case IB_CM_TIMEWAIT_EXIT:
2716 2717
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "connection closed\n");
2718
		comp = 1;
2719

2720
		ch->status = 0;
2721 2722
		break;

2723 2724 2725 2726 2727
	case IB_CM_MRA_RECEIVED:
	case IB_CM_DREQ_ERROR:
	case IB_CM_DREP_RECEIVED:
		break;

2728
	default:
2729 2730
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled CM event %d\n", event->event);
2731 2732 2733 2734
		break;
	}

	if (comp)
2735
		complete(&ch->done);
2736 2737 2738 2739

	return 0;
}

B
Bart Van Assche 已提交
2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868
static void srp_rdma_cm_rej_handler(struct srp_rdma_ch *ch,
				    struct rdma_cm_event *event)
{
	struct srp_target_port *target = ch->target;
	struct Scsi_Host *shost = target->scsi_host;
	int opcode;

	switch (event->status) {
	case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
		shost_printk(KERN_WARNING, shost,
			    "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
		ch->status = -ECONNRESET;
		break;

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

			if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
				shost_printk(KERN_WARNING, shost,
					     PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
			else
				shost_printk(KERN_WARNING, shost,
					    PFX "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
		} else {
			shost_printk(KERN_WARNING, shost,
				     "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED, opcode 0x%02x\n",
				     opcode);
		}
		ch->status = -ECONNRESET;
		break;

	case IB_CM_REJ_STALE_CONN:
		shost_printk(KERN_WARNING, shost,
			     "  REJ reason: stale connection\n");
		ch->status = SRP_STALE_CONN;
		break;

	default:
		shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
			     event->status);
		ch->status = -ECONNRESET;
		break;
	}
}

static int srp_rdma_cm_handler(struct rdma_cm_id *cm_id,
			       struct rdma_cm_event *event)
{
	struct srp_rdma_ch *ch = cm_id->context;
	struct srp_target_port *target = ch->target;
	int comp = 0;

	switch (event->event) {
	case RDMA_CM_EVENT_ADDR_RESOLVED:
		ch->status = 0;
		comp = 1;
		break;

	case RDMA_CM_EVENT_ADDR_ERROR:
		ch->status = -ENXIO;
		comp = 1;
		break;

	case RDMA_CM_EVENT_ROUTE_RESOLVED:
		ch->status = 0;
		comp = 1;
		break;

	case RDMA_CM_EVENT_ROUTE_ERROR:
	case RDMA_CM_EVENT_UNREACHABLE:
		ch->status = -EHOSTUNREACH;
		comp = 1;
		break;

	case RDMA_CM_EVENT_CONNECT_ERROR:
		shost_printk(KERN_DEBUG, target->scsi_host,
			     PFX "Sending CM REQ failed\n");
		comp = 1;
		ch->status = -ECONNRESET;
		break;

	case RDMA_CM_EVENT_ESTABLISHED:
		comp = 1;
		srp_cm_rep_handler(NULL, event->param.conn.private_data, ch);
		break;

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

		srp_rdma_cm_rej_handler(ch, event);
		break;

	case RDMA_CM_EVENT_DISCONNECTED:
		if (ch->connected) {
			shost_printk(KERN_WARNING, target->scsi_host,
				     PFX "received DREQ\n");
			rdma_disconnect(ch->rdma_cm.cm_id);
			comp = 1;
			ch->status = 0;
			queue_work(system_long_wq, &target->tl_err_work);
		}
		break;

	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
		shost_printk(KERN_ERR, target->scsi_host,
			     PFX "connection closed\n");

		comp = 1;
		ch->status = 0;
		break;

	default:
		shost_printk(KERN_WARNING, target->scsi_host,
			     PFX "Unhandled CM event %d\n", event->event);
		break;
	}

	if (comp)
		complete(&ch->done);

	return 0;
}

2869 2870 2871 2872 2873 2874 2875 2876
/**
 * srp_change_queue_depth - setting device queue depth
 * @sdev: scsi device struct
 * @qdepth: requested queue depth
 *
 * Returns queue depth.
 */
static int
2877
srp_change_queue_depth(struct scsi_device *sdev, int qdepth)
2878
{
2879
	if (!sdev->tagged_supported)
2880
		qdepth = 1;
2881
	return scsi_change_queue_depth(sdev, qdepth);
2882 2883
}

B
Bart Van Assche 已提交
2884
static int srp_send_tsk_mgmt(struct srp_rdma_ch *ch, u64 req_tag, u64 lun,
2885
			     u8 func, u8 *status)
2886
{
2887
	struct srp_target_port *target = ch->target;
2888
	struct srp_rport *rport = target->rport;
2889
	struct ib_device *dev = target->srp_host->srp_dev->dev;
2890 2891
	struct srp_iu *iu;
	struct srp_tsk_mgmt *tsk_mgmt;
2892
	int res;
2893

2894
	if (!ch->connected || target->qp_in_error)
2895 2896
		return -1;

2897
	/*
2898
	 * Lock the rport mutex to avoid that srp_create_ch_ib() is
2899 2900 2901
	 * invoked while a task management function is being sent.
	 */
	mutex_lock(&rport->mutex);
2902 2903 2904
	spin_lock_irq(&ch->lock);
	iu = __srp_get_tx_iu(ch, SRP_IU_TSK_MGMT);
	spin_unlock_irq(&ch->lock);
2905

2906 2907 2908
	if (!iu) {
		mutex_unlock(&rport->mutex);

2909
		return -1;
2910
	}
2911

2912 2913
	ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
				   DMA_TO_DEVICE);
2914 2915 2916 2917
	tsk_mgmt = iu->buf;
	memset(tsk_mgmt, 0, sizeof *tsk_mgmt);

	tsk_mgmt->opcode 	= SRP_TSK_MGMT;
B
Bart Van Assche 已提交
2918
	int_to_scsilun(lun, &tsk_mgmt->lun);
2919
	tsk_mgmt->tsk_mgmt_func = func;
2920
	tsk_mgmt->task_tag	= req_tag;
2921

2922 2923 2924 2925 2926 2927 2928
	spin_lock_irq(&ch->lock);
	ch->tsk_mgmt_tag = (ch->tsk_mgmt_tag + 1) | SRP_TAG_TSK_MGMT;
	tsk_mgmt->tag = ch->tsk_mgmt_tag;
	spin_unlock_irq(&ch->lock);

	init_completion(&ch->tsk_mgmt_done);

2929 2930
	ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
				      DMA_TO_DEVICE);
2931 2932
	if (srp_post_send(ch, iu, sizeof(*tsk_mgmt))) {
		srp_put_tx_iu(ch, iu, SRP_IU_TSK_MGMT);
2933 2934
		mutex_unlock(&rport->mutex);

2935 2936
		return -1;
	}
2937 2938 2939 2940
	res = wait_for_completion_timeout(&ch->tsk_mgmt_done,
					msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS));
	if (res > 0 && status)
		*status = ch->tsk_mgmt_status;
2941
	mutex_unlock(&rport->mutex);
2942

2943
	WARN_ON_ONCE(res < 0);
2944

2945
	return res > 0 ? 0 : -1;
2946 2947
}

2948 2949
static int srp_abort(struct scsi_cmnd *scmnd)
{
2950
	struct srp_target_port *target = host_to_target(scmnd->device->host);
2951
	struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
B
Bart Van Assche 已提交
2952
	u32 tag;
B
Bart Van Assche 已提交
2953
	u16 ch_idx;
2954
	struct srp_rdma_ch *ch;
2955
	int ret;
2956

2957
	shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
2958

B
Bart Van Assche 已提交
2959
	if (!req)
2960
		return SUCCESS;
B
Bart Van Assche 已提交
2961
	tag = blk_mq_unique_tag(scmnd->request);
B
Bart Van Assche 已提交
2962 2963 2964 2965 2966 2967 2968 2969
	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
2970
	if (srp_send_tsk_mgmt(ch, tag, scmnd->device->lun,
2971
			      SRP_TSK_ABORT_TASK, NULL) == 0)
2972
		ret = SUCCESS;
2973
	else if (target->rport->state == SRP_RPORT_LOST)
2974
		ret = FAST_IO_FAIL;
2975 2976
	else
		ret = FAILED;
B
Bart Van Assche 已提交
2977 2978 2979 2980 2981
	if (ret == SUCCESS) {
		srp_free_req(ch, req, scmnd, 0);
		scmnd->result = DID_ABORT << 16;
		scmnd->scsi_done(scmnd);
	}
2982

2983
	return ret;
2984 2985 2986 2987
}

static int srp_reset_device(struct scsi_cmnd *scmnd)
{
2988
	struct srp_target_port *target = host_to_target(scmnd->device->host);
B
Bart Van Assche 已提交
2989
	struct srp_rdma_ch *ch;
2990
	int i;
2991
	u8 status;
2992

2993
	shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
2994

B
Bart Van Assche 已提交
2995
	ch = &target->ch[0];
2996
	if (srp_send_tsk_mgmt(ch, SRP_TAG_NO_REQ, scmnd->device->lun,
2997
			      SRP_TSK_LUN_RESET, &status))
2998
		return FAILED;
2999
	if (status)
3000 3001
		return FAILED;

B
Bart Van Assche 已提交
3002 3003 3004 3005
	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];
3006

B
Bart Van Assche 已提交
3007 3008
			srp_finish_req(ch, req, scmnd->device, DID_RESET << 16);
		}
3009
	}
3010 3011

	return SUCCESS;
3012 3013 3014 3015 3016 3017
}

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

3018
	shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
3019

3020
	return srp_reconnect_rport(target->rport) == 0 ? SUCCESS : FAILED;
3021 3022
}

3023 3024 3025 3026 3027 3028 3029 3030 3031 3032
static int srp_target_alloc(struct scsi_target *starget)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct srp_target_port *target = host_to_target(shost);

	if (target->target_can_queue)
		starget->can_queue = target->target_can_queue;
	return 0;
}

3033 3034 3035 3036 3037 3038
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;

3039
	if (true)
3040 3041 3042 3043 3044 3045
		blk_queue_virt_boundary(sdev->request_queue,
					~srp_dev->mr_page_mask);

	return 0;
}

3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060
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;
}

3061 3062
static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
			   char *buf)
3063
{
3064
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
3065

3066
	return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->id_ext));
3067 3068
}

3069 3070
static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
			     char *buf)
3071
{
3072
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
3073

3074
	return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->ioc_guid));
3075 3076
}

3077 3078
static ssize_t show_service_id(struct device *dev,
			       struct device_attribute *attr, char *buf)
3079
{
3080
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
3081

B
Bart Van Assche 已提交
3082 3083 3084 3085
	if (target->using_rdma_cm)
		return -ENOENT;
	return sprintf(buf, "0x%016llx\n",
		       be64_to_cpu(target->ib_cm.service_id));
3086 3087
}

3088 3089
static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
			 char *buf)
3090
{
3091
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
3092

B
Bart Van Assche 已提交
3093 3094 3095
	if (target->using_rdma_cm)
		return -ENOENT;
	return sprintf(buf, "0x%04x\n", be16_to_cpu(target->ib_cm.pkey));
3096 3097
}

B
Bart Van Assche 已提交
3098 3099 3100 3101 3102
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));

3103
	return sprintf(buf, "%pI6\n", target->sgid.raw);
B
Bart Van Assche 已提交
3104 3105
}

3106 3107
static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
			 char *buf)
3108
{
3109
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
B
Bart Van Assche 已提交
3110
	struct srp_rdma_ch *ch = &target->ch[0];
3111

B
Bart Van Assche 已提交
3112 3113 3114
	if (target->using_rdma_cm)
		return -ENOENT;
	return sprintf(buf, "%pI6\n", ch->ib_cm.path.dgid.raw);
3115 3116
}

3117 3118
static ssize_t show_orig_dgid(struct device *dev,
			      struct device_attribute *attr, char *buf)
3119
{
3120
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
3121

B
Bart Van Assche 已提交
3122 3123 3124
	if (target->using_rdma_cm)
		return -ENOENT;
	return sprintf(buf, "%pI6\n", target->ib_cm.orig_dgid.raw);
3125 3126
}

3127 3128 3129 3130
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
3131 3132
	struct srp_rdma_ch *ch;
	int i, req_lim = INT_MAX;
3133

B
Bart Van Assche 已提交
3134 3135 3136 3137 3138
	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);
3139 3140
}

3141 3142
static ssize_t show_zero_req_lim(struct device *dev,
				 struct device_attribute *attr, char *buf)
3143
{
3144
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
3145 3146 3147 3148

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

3149 3150
static ssize_t show_local_ib_port(struct device *dev,
				  struct device_attribute *attr, char *buf)
3151
{
3152
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
3153 3154 3155 3156

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

3157 3158
static ssize_t show_local_ib_device(struct device *dev,
				    struct device_attribute *attr, char *buf)
3159
{
3160
	struct srp_target_port *target = host_to_target(class_to_shost(dev));
3161

3162
	return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
3163 3164
}

B
Bart Van Assche 已提交
3165 3166 3167 3168 3169 3170 3171 3172
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);
}

3173 3174 3175 3176 3177 3178 3179 3180
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);
}

3181 3182 3183 3184 3185 3186 3187 3188
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);
}

3189 3190 3191 3192 3193 3194 3195 3196
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);
}

3197 3198 3199 3200 3201 3202 3203 3204
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");
}

3205 3206 3207 3208
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
3209
static DEVICE_ATTR(sgid,	    S_IRUGO, show_sgid,		   NULL);
3210 3211
static DEVICE_ATTR(dgid,	    S_IRUGO, show_dgid,		   NULL);
static DEVICE_ATTR(orig_dgid,	    S_IRUGO, show_orig_dgid,	   NULL);
3212
static DEVICE_ATTR(req_lim,         S_IRUGO, show_req_lim,         NULL);
3213 3214 3215
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
3216
static DEVICE_ATTR(ch_count,        S_IRUGO, show_ch_count,        NULL);
3217
static DEVICE_ATTR(comp_vector,     S_IRUGO, show_comp_vector,     NULL);
3218
static DEVICE_ATTR(tl_retry_count,  S_IRUGO, show_tl_retry_count,  NULL);
3219
static DEVICE_ATTR(cmd_sg_entries,  S_IRUGO, show_cmd_sg_entries,  NULL);
3220
static DEVICE_ATTR(allow_ext_sg,    S_IRUGO, show_allow_ext_sg,    NULL);
3221 3222 3223 3224 3225 3226

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
3227
	&dev_attr_sgid,
3228 3229
	&dev_attr_dgid,
	&dev_attr_orig_dgid,
3230
	&dev_attr_req_lim,
3231 3232 3233
	&dev_attr_zero_req_lim,
	&dev_attr_local_ib_port,
	&dev_attr_local_ib_device,
B
Bart Van Assche 已提交
3234
	&dev_attr_ch_count,
3235
	&dev_attr_comp_vector,
3236
	&dev_attr_tl_retry_count,
3237
	&dev_attr_cmd_sg_entries,
3238
	&dev_attr_allow_ext_sg,
3239 3240 3241
	NULL
};

3242 3243
static struct scsi_host_template srp_template = {
	.module				= THIS_MODULE,
R
Roland Dreier 已提交
3244 3245
	.name				= "InfiniBand SRP initiator",
	.proc_name			= DRV_NAME,
3246
	.target_alloc			= srp_target_alloc,
3247
	.slave_alloc			= srp_slave_alloc,
3248
	.slave_configure		= srp_slave_configure,
3249 3250
	.info				= srp_target_info,
	.queuecommand			= srp_queuecommand,
3251
	.change_queue_depth             = srp_change_queue_depth,
3252
	.eh_timed_out			= srp_timed_out,
3253 3254 3255
	.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
3256
	.skip_settle_delay		= true,
3257
	.sg_tablesize			= SRP_DEF_SG_TABLESIZE,
3258
	.can_queue			= SRP_DEFAULT_CMD_SQ_SIZE,
3259
	.this_id			= -1,
3260
	.cmd_per_lun			= SRP_DEFAULT_CMD_SQ_SIZE,
3261
	.use_clustering			= ENABLE_CLUSTERING,
B
Bart Van Assche 已提交
3262
	.shost_attrs			= srp_host_attrs,
3263
	.track_queue_depth		= 1,
3264 3265
};

3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276
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;
}

3277 3278 3279 3280 3281 3282 3283
/*
 * 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.
 */
3284 3285
static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
{
3286 3287 3288
	struct srp_rport_identifiers ids;
	struct srp_rport *rport;

3289
	target->state = SRP_TARGET_SCANNING;
3290
	sprintf(target->target_name, "SRP.T10:%016llX",
3291
		be64_to_cpu(target->id_ext));
3292

3293
	if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dev.parent))
3294 3295
		return -ENODEV;

3296 3297
	memcpy(ids.port_id, &target->id_ext, 8);
	memcpy(ids.port_id + 8, &target->ioc_guid, 8);
3298
	ids.roles = SRP_RPORT_ROLE_TARGET;
3299 3300 3301 3302 3303 3304
	rport = srp_rport_add(target->scsi_host, &ids);
	if (IS_ERR(rport)) {
		scsi_remove_host(target->scsi_host);
		return PTR_ERR(rport);
	}

3305
	rport->lld_data = target;
3306
	target->rport = rport;
3307

3308
	spin_lock(&host->target_lock);
3309
	list_add_tail(&target->list, &host->target_list);
3310
	spin_unlock(&host->target_lock);
3311 3312

	scsi_scan_target(&target->scsi_host->shost_gendev,
3313
			 0, target->scsi_id, SCAN_WILD_CARD, SCSI_SCAN_INITIAL);
3314

3315 3316
	if (srp_connected_ch(target) < target->ch_count ||
	    target->qp_in_error) {
3317 3318 3319 3320 3321 3322
		shost_printk(KERN_INFO, target->scsi_host,
			     PFX "SCSI scan failed - removing SCSI host\n");
		srp_queue_remove_work(target);
		goto out;
	}

3323
	pr_debug("%s: SCSI scan succeeded - detected %d LUNs\n",
3324 3325 3326 3327 3328 3329 3330 3331 3332
		 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:
3333 3334 3335
	return 0;
}

3336
static void srp_release_dev(struct device *dev)
3337 3338
{
	struct srp_host *host =
3339
		container_of(dev, struct srp_host, dev);
3340 3341 3342 3343 3344 3345

	complete(&host->released);
}

static struct class srp_class = {
	.name    = "infiniband_srp",
3346
	.dev_release = srp_release_dev
3347 3348
};

3349 3350
/**
 * srp_conn_unique() - check whether the connection to a target is unique
3351 3352
 * @host:   SRP host.
 * @target: SRP target port.
3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369
 */
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 &&
B
Bart Van Assche 已提交
3370 3371 3372
		    (!target->using_rdma_cm ||
		     memcmp(&target->rdma_cm.dst, &t->rdma_cm.dst,
			    sizeof(target->rdma_cm.dst)) == 0) &&
3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383
		    target->initiator_ext == t->initiator_ext) {
			ret = false;
			break;
		}
	}
	spin_unlock(&host->target_lock);

out:
	return ret;
}

3384 3385 3386 3387 3388
/*
 * 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>
B
Bart Van Assche 已提交
3389 3390 3391
 * or
 *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,
 *     [src=<IPv4 address>,]dest=<IPv4 address>:<port number>
3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402
 *
 * 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,
3403
	SRP_OPT_MAX_CMD_PER_LUN	= 1 << 6,
3404
	SRP_OPT_IO_CLASS	= 1 << 7,
3405
	SRP_OPT_INITIATOR_EXT	= 1 << 8,
3406
	SRP_OPT_CMD_SG_ENTRIES	= 1 << 9,
3407 3408
	SRP_OPT_ALLOW_EXT_SG	= 1 << 10,
	SRP_OPT_SG_TABLESIZE	= 1 << 11,
3409
	SRP_OPT_COMP_VECTOR	= 1 << 12,
3410
	SRP_OPT_TL_RETRY_COUNT	= 1 << 13,
3411
	SRP_OPT_QUEUE_SIZE	= 1 << 14,
B
Bart Van Assche 已提交
3412 3413
	SRP_OPT_IP_SRC		= 1 << 15,
	SRP_OPT_IP_DEST		= 1 << 16,
3414
	SRP_OPT_TARGET_CAN_QUEUE= 1 << 17,
B
Bart Van Assche 已提交
3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425
};

static unsigned int srp_opt_mandatory[] = {
	SRP_OPT_ID_EXT		|
	SRP_OPT_IOC_GUID	|
	SRP_OPT_DGID		|
	SRP_OPT_PKEY		|
	SRP_OPT_SERVICE_ID,
	SRP_OPT_ID_EXT		|
	SRP_OPT_IOC_GUID	|
	SRP_OPT_IP_DEST,
3426 3427
};

3428
static const match_table_t srp_opt_tokens = {
3429 3430 3431 3432 3433 3434 3435
	{ 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" 	},
3436
	{ SRP_OPT_TARGET_CAN_QUEUE,	"target_can_queue=%d"	},
3437
	{ SRP_OPT_IO_CLASS,		"io_class=%x"		},
3438
	{ SRP_OPT_INITIATOR_EXT,	"initiator_ext=%s"	},
3439
	{ SRP_OPT_CMD_SG_ENTRIES,	"cmd_sg_entries=%u"	},
3440 3441
	{ SRP_OPT_ALLOW_EXT_SG,		"allow_ext_sg=%u"	},
	{ SRP_OPT_SG_TABLESIZE,		"sg_tablesize=%u"	},
3442
	{ SRP_OPT_COMP_VECTOR,		"comp_vector=%u"	},
3443
	{ SRP_OPT_TL_RETRY_COUNT,	"tl_retry_count=%u"	},
3444
	{ SRP_OPT_QUEUE_SIZE,		"queue_size=%d"		},
B
Bart Van Assche 已提交
3445 3446
	{ SRP_OPT_IP_SRC,		"src=%s"		},
	{ SRP_OPT_IP_DEST,		"dest=%s"		},
3447
	{ SRP_OPT_ERR,			NULL 			}
3448 3449
};

B
Bart Van Assche 已提交
3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466
static int srp_parse_in(struct net *net, struct sockaddr_storage *sa,
			const char *addr_port_str)
{
	char *addr = kstrdup(addr_port_str, GFP_KERNEL);
	char *port_str = addr;
	int ret;

	if (!addr)
		return -ENOMEM;
	strsep(&port_str, ":");
	ret = inet_pton_with_scope(net, AF_UNSPEC, addr, port_str, sa);
	kfree(addr);
	return ret;
}

static int srp_parse_options(struct net *net, const char *buf,
			     struct srp_target_port *target)
3467 3468 3469 3470
{
	char *options, *sep_opt;
	char *p;
	substring_t args[MAX_OPT_ARGS];
3471
	unsigned long long ull;
3472 3473 3474 3475 3476 3477 3478 3479 3480 3481
	int opt_mask = 0;
	int token;
	int ret = -EINVAL;
	int i;

	options = kstrdup(buf, GFP_KERNEL);
	if (!options)
		return -ENOMEM;

	sep_opt = options;
3482
	while ((p = strsep(&sep_opt, ",\n")) != NULL) {
3483 3484 3485 3486 3487 3488 3489 3490 3491
		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);
3492 3493 3494 3495
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3496 3497 3498 3499 3500 3501 3502
			ret = kstrtoull(p, 16, &ull);
			if (ret) {
				pr_warn("invalid id_ext parameter '%s'\n", p);
				kfree(p);
				goto out;
			}
			target->id_ext = cpu_to_be64(ull);
3503 3504 3505 3506 3507
			kfree(p);
			break;

		case SRP_OPT_IOC_GUID:
			p = match_strdup(args);
3508 3509 3510 3511
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3512 3513 3514 3515 3516 3517 3518
			ret = kstrtoull(p, 16, &ull);
			if (ret) {
				pr_warn("invalid ioc_guid parameter '%s'\n", p);
				kfree(p);
				goto out;
			}
			target->ioc_guid = cpu_to_be64(ull);
3519 3520 3521 3522 3523
			kfree(p);
			break;

		case SRP_OPT_DGID:
			p = match_strdup(args);
3524 3525 3526 3527
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3528
			if (strlen(p) != 32) {
3529
				pr_warn("bad dest GID parameter '%s'\n", p);
3530
				kfree(p);
3531 3532 3533
				goto out;
			}

B
Bart Van Assche 已提交
3534
			ret = hex2bin(target->ib_cm.orig_dgid.raw, p, 16);
3535
			kfree(p);
3536 3537
			if (ret < 0)
				goto out;
3538 3539 3540 3541
			break;

		case SRP_OPT_PKEY:
			if (match_hex(args, &token)) {
3542
				pr_warn("bad P_Key parameter '%s'\n", p);
3543 3544
				goto out;
			}
B
Bart Van Assche 已提交
3545
			target->ib_cm.pkey = cpu_to_be16(token);
3546 3547 3548 3549
			break;

		case SRP_OPT_SERVICE_ID:
			p = match_strdup(args);
3550 3551 3552 3553
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3554 3555 3556 3557 3558 3559
			ret = kstrtoull(p, 16, &ull);
			if (ret) {
				pr_warn("bad service_id parameter '%s'\n", p);
				kfree(p);
				goto out;
			}
B
Bart Van Assche 已提交
3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592
			target->ib_cm.service_id = cpu_to_be64(ull);
			kfree(p);
			break;

		case SRP_OPT_IP_SRC:
			p = match_strdup(args);
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
			ret = srp_parse_in(net, &target->rdma_cm.src.ss, p);
			if (ret < 0) {
				pr_warn("bad source parameter '%s'\n", p);
				kfree(p);
				goto out;
			}
			target->rdma_cm.src_specified = true;
			kfree(p);
			break;

		case SRP_OPT_IP_DEST:
			p = match_strdup(args);
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
			ret = srp_parse_in(net, &target->rdma_cm.dst.ss, p);
			if (ret < 0) {
				pr_warn("bad dest parameter '%s'\n", p);
				kfree(p);
				goto out;
			}
			target->using_rdma_cm = true;
3593 3594 3595 3596 3597
			kfree(p);
			break;

		case SRP_OPT_MAX_SECT:
			if (match_int(args, &token)) {
3598
				pr_warn("bad max sect parameter '%s'\n", p);
3599 3600 3601 3602 3603
				goto out;
			}
			target->scsi_host->max_sectors = token;
			break;

3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615
		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;

3616
		case SRP_OPT_MAX_CMD_PER_LUN:
3617
			if (match_int(args, &token) || token < 1) {
3618 3619
				pr_warn("bad max cmd_per_lun parameter '%s'\n",
					p);
3620 3621
				goto out;
			}
3622
			target->scsi_host->cmd_per_lun = token;
3623 3624
			break;

3625 3626 3627 3628 3629 3630 3631 3632 3633
		case SRP_OPT_TARGET_CAN_QUEUE:
			if (match_int(args, &token) || token < 1) {
				pr_warn("bad max target_can_queue parameter '%s'\n",
					p);
				goto out;
			}
			target->target_can_queue = token;
			break;

3634 3635
		case SRP_OPT_IO_CLASS:
			if (match_hex(args, &token)) {
3636
				pr_warn("bad IO class parameter '%s'\n", p);
3637 3638 3639 3640
				goto out;
			}
			if (token != SRP_REV10_IB_IO_CLASS &&
			    token != SRP_REV16A_IB_IO_CLASS) {
3641 3642 3643
				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);
3644 3645 3646 3647 3648
				goto out;
			}
			target->io_class = token;
			break;

3649 3650
		case SRP_OPT_INITIATOR_EXT:
			p = match_strdup(args);
3651 3652 3653 3654
			if (!p) {
				ret = -ENOMEM;
				goto out;
			}
3655 3656 3657 3658 3659 3660 3661
			ret = kstrtoull(p, 16, &ull);
			if (ret) {
				pr_warn("bad initiator_ext value '%s'\n", p);
				kfree(p);
				goto out;
			}
			target->initiator_ext = cpu_to_be64(ull);
3662 3663 3664
			kfree(p);
			break;

3665 3666
		case SRP_OPT_CMD_SG_ENTRIES:
			if (match_int(args, &token) || token < 1 || token > 255) {
3667 3668
				pr_warn("bad max cmd_sg_entries parameter '%s'\n",
					p);
3669 3670 3671 3672 3673
				goto out;
			}
			target->cmd_sg_cnt = token;
			break;

3674 3675
		case SRP_OPT_ALLOW_EXT_SG:
			if (match_int(args, &token)) {
3676
				pr_warn("bad allow_ext_sg parameter '%s'\n", p);
3677 3678 3679 3680 3681 3682 3683
				goto out;
			}
			target->allow_ext_sg = !!token;
			break;

		case SRP_OPT_SG_TABLESIZE:
			if (match_int(args, &token) || token < 1 ||
3684
					token > SG_MAX_SEGMENTS) {
3685 3686
				pr_warn("bad max sg_tablesize parameter '%s'\n",
					p);
3687 3688 3689 3690 3691
				goto out;
			}
			target->sg_tablesize = token;
			break;

3692 3693 3694 3695 3696 3697 3698 3699
		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;

3700 3701 3702 3703 3704 3705 3706 3707 3708
		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;

3709
		default:
3710 3711
			pr_warn("unknown parameter or missing value '%s' in target creation request\n",
				p);
3712 3713 3714 3715
			goto out;
		}
	}

B
Bart Van Assche 已提交
3716 3717 3718 3719 3720 3721 3722 3723
	for (i = 0; i < ARRAY_SIZE(srp_opt_mandatory); i++) {
		if ((opt_mask & srp_opt_mandatory[i]) == srp_opt_mandatory[i]) {
			ret = 0;
			break;
		}
	}
	if (ret)
		pr_warn("target creation request is missing one or more parameters\n");
3724

3725 3726 3727 3728 3729 3730
	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);

3731 3732 3733 3734 3735
out:
	kfree(options);
	return ret;
}

3736 3737
static ssize_t srp_create_target(struct device *dev,
				 struct device_attribute *attr,
3738 3739 3740
				 const char *buf, size_t count)
{
	struct srp_host *host =
3741
		container_of(dev, struct srp_host, dev);
3742 3743
	struct Scsi_Host *target_host;
	struct srp_target_port *target;
3744
	struct srp_rdma_ch *ch;
3745 3746
	struct srp_device *srp_dev = host->srp_dev;
	struct ib_device *ibdev = srp_dev->dev;
B
Bart Van Assche 已提交
3747
	int ret, node_idx, node, cpu, i;
3748
	unsigned int max_sectors_per_mr, mr_per_cmd = 0;
B
Bart Van Assche 已提交
3749
	bool multich = false;
3750 3751 3752 3753 3754 3755

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

3756
	target_host->transportt  = ib_srp_transport_template;
3757 3758
	target_host->max_channel = 0;
	target_host->max_id      = 1;
B
Bart Van Assche 已提交
3759
	target_host->max_lun     = -1LL;
A
Arne Redlich 已提交
3760
	target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
R
Roland Dreier 已提交
3761

3762 3763
	target = host_to_target(target_host);

B
Bart Van Assche 已提交
3764
	target->net		= kobj_ns_grab_current(KOBJ_NS_TYPE_NET);
3765 3766 3767
	target->io_class	= SRP_REV16A_IB_IO_CLASS;
	target->scsi_host	= target_host;
	target->srp_host	= host;
J
Jason Gunthorpe 已提交
3768
	target->lkey		= host->srp_dev->pd->local_dma_lkey;
B
Bart Van Assche 已提交
3769
	target->global_rkey	= host->srp_dev->global_rkey;
3770
	target->cmd_sg_cnt	= cmd_sg_entries;
3771 3772
	target->sg_tablesize	= indirect_sg_entries ? : cmd_sg_entries;
	target->allow_ext_sg	= allow_ext_sg;
3773
	target->tl_retry_count	= 7;
3774
	target->queue_size	= SRP_DEFAULT_QUEUE_SIZE;
3775

3776 3777 3778 3779 3780 3781
	/*
	 * Avoid that the SCSI host can be removed by srp_remove_target()
	 * before this function returns.
	 */
	scsi_host_get(target->scsi_host);

3782 3783 3784
	ret = mutex_lock_interruptible(&host->add_target_mutex);
	if (ret < 0)
		goto put;
3785

B
Bart Van Assche 已提交
3786
	ret = srp_parse_options(target->net, buf, target);
3787
	if (ret)
3788
		goto out;
3789

3790 3791
	target->req_ring_size = target->queue_size - SRP_TSK_MGMT_SQ_SIZE;

3792
	if (!srp_conn_unique(target->srp_host, target)) {
B
Bart Van Assche 已提交
3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808
		if (target->using_rdma_cm) {
			char dst_addr[64];

			shost_printk(KERN_INFO, target->scsi_host,
				     PFX "Already connected to target port with id_ext=%016llx;ioc_guid=%016llx;dest=%s\n",
				     be64_to_cpu(target->id_ext),
				     be64_to_cpu(target->ioc_guid),
				     inet_ntop(&target->rdma_cm.dst, dst_addr,
					       sizeof(dst_addr)));
		} else {
			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));
		}
3809
		ret = -EEXIST;
3810
		goto out;
3811 3812
	}

3813
	if (!srp_dev->has_fmr && !srp_dev->has_fr && !target->allow_ext_sg &&
3814
	    target->cmd_sg_cnt < target->sg_tablesize) {
3815
		pr_warn("No MR pool and no external indirect descriptors, limiting sg_tablesize to cmd_sg_cnt\n");
3816 3817 3818
		target->sg_tablesize = target->cmd_sg_cnt;
	}

3819 3820 3821 3822 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840 3841 3842
	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);
	}

3843
	target_host->sg_tablesize = target->sg_tablesize;
3844 3845
	target->mr_pool_size = target->scsi_host->can_queue * mr_per_cmd;
	target->mr_per_cmd = mr_per_cmd;
3846 3847
	target->indirect_size = target->sg_tablesize *
				sizeof (struct srp_direct_buf);
3848 3849 3850 3851
	target->max_iu_len = sizeof (struct srp_cmd) +
			     sizeof (struct srp_indirect_buf) +
			     target->cmd_sg_cnt * sizeof (struct srp_direct_buf);

3852
	INIT_WORK(&target->tl_err_work, srp_tl_err_work);
3853
	INIT_WORK(&target->remove_work, srp_remove_work);
3854
	spin_lock_init(&target->lock);
3855
	ret = ib_query_gid(ibdev, host->port, 0, &target->sgid, NULL);
3856
	if (ret)
3857
		goto out;
3858

B
Bart Van Assche 已提交
3859 3860 3861 3862 3863 3864 3865 3866 3867
	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)
3868
		goto out;
3869

B
Bart Van Assche 已提交
3870 3871 3872 3873 3874 3875
	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());
3876 3877 3878 3879
		const int cv_start = node_idx * ibdev->num_comp_vectors /
				     num_online_nodes();
		const int cv_end = (node_idx + 1) * ibdev->num_comp_vectors /
				   num_online_nodes();
B
Bart Van Assche 已提交
3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895
		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;
3896

B
Bart Van Assche 已提交
3897 3898 3899 3900 3901 3902 3903 3904 3905 3906
			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) {
B
Bart Van Assche 已提交
3907 3908 3909 3910 3911 3912 3913 3914
				char dst[64];

				if (target->using_rdma_cm)
					inet_ntop(&target->rdma_cm.dst, dst,
						  sizeof(dst));
				else
					snprintf(dst, sizeof(dst), "%pI6",
						 target->ib_cm.orig_dgid.raw);
B
Bart Van Assche 已提交
3915
				shost_printk(KERN_ERR, target->scsi_host,
B
Bart Van Assche 已提交
3916
					     PFX "Connection %d/%d to %s failed\n",
B
Bart Van Assche 已提交
3917
					     ch_start + cpu_idx,
B
Bart Van Assche 已提交
3918
					     target->ch_count, dst);
B
Bart Van Assche 已提交
3919
				if (node_idx == 0 && cpu_idx == 0) {
B
Bart Van Assche 已提交
3920
					goto free_ch;
B
Bart Van Assche 已提交
3921 3922 3923 3924
				} else {
					srp_free_ch_ib(target, ch);
					srp_free_req_data(target, ch);
					target->ch_count = ch - target->ch;
3925
					goto connected;
B
Bart Van Assche 已提交
3926 3927 3928 3929 3930 3931 3932
				}
			}

			multich = true;
			cpu_idx++;
		}
		node_idx++;
3933 3934
	}

3935
connected:
B
Bart Van Assche 已提交
3936 3937
	target->scsi_host->nr_hw_queues = target->ch_count;

3938 3939 3940 3941
	ret = srp_add_target(host, target);
	if (ret)
		goto err_disconnect;

3942
	if (target->state != SRP_TARGET_REMOVED) {
B
Bart Van Assche 已提交
3943 3944 3945 3946 3947 3948 3949 3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961
		if (target->using_rdma_cm) {
			char dst[64];

			inet_ntop(&target->rdma_cm.dst, dst, sizeof(dst));
			shost_printk(KERN_DEBUG, target->scsi_host, PFX
				     "new target: id_ext %016llx ioc_guid %016llx sgid %pI6 dest %s\n",
				     be64_to_cpu(target->id_ext),
				     be64_to_cpu(target->ioc_guid),
				     target->sgid.raw, dst);
		} else {
			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),
				     be16_to_cpu(target->ib_cm.pkey),
				     be64_to_cpu(target->ib_cm.service_id),
				     target->sgid.raw,
				     target->ib_cm.orig_dgid.raw);
		}
3962
	}
B
Bart Van Assche 已提交
3963

3964 3965 3966 3967
	ret = count;

out:
	mutex_unlock(&host->add_target_mutex);
3968

3969
put:
3970
	scsi_host_put(target->scsi_host);
B
Bart Van Assche 已提交
3971 3972 3973 3974 3975 3976 3977 3978
	if (ret < 0) {
		/*
		 * If a call to srp_remove_target() has not been scheduled,
		 * drop the network namespace reference now that was obtained
		 * earlier in this function.
		 */
		if (target->state != SRP_TARGET_REMOVED)
			kobj_ns_drop(KOBJ_NS_TYPE_NET, target->net);
3979
		scsi_host_put(target->scsi_host);
B
Bart Van Assche 已提交
3980
	}
3981

3982
	return ret;
3983 3984 3985 3986

err_disconnect:
	srp_disconnect_target(target);

B
Bart Van Assche 已提交
3987
free_ch:
B
Bart Van Assche 已提交
3988 3989 3990 3991 3992
	for (i = 0; i < target->ch_count; i++) {
		ch = &target->ch[i];
		srp_free_ch_ib(target, ch);
		srp_free_req_data(target, ch);
	}
3993

B
Bart Van Assche 已提交
3994
	kfree(target->ch);
3995
	goto out;
3996 3997
}

3998
static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
3999

4000 4001
static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
			  char *buf)
4002
{
4003
	struct srp_host *host = container_of(dev, struct srp_host, dev);
4004

4005
	return sprintf(buf, "%s\n", host->srp_dev->dev->name);
4006 4007
}

4008
static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
4009

4010 4011
static ssize_t show_port(struct device *dev, struct device_attribute *attr,
			 char *buf)
4012
{
4013
	struct srp_host *host = container_of(dev, struct srp_host, dev);
4014 4015 4016 4017

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

4018
static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
4019

4020
static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
4021 4022 4023 4024 4025 4026 4027 4028
{
	struct srp_host *host;

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

	INIT_LIST_HEAD(&host->target_list);
4029
	spin_lock_init(&host->target_lock);
4030
	init_completion(&host->released);
4031
	mutex_init(&host->add_target_mutex);
4032
	host->srp_dev = device;
4033 4034
	host->port = port;

4035
	host->dev.class = &srp_class;
4036
	host->dev.parent = device->dev->dev.parent;
4037
	dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
4038

4039
	if (device_register(&host->dev))
4040
		goto free_host;
4041
	if (device_create_file(&host->dev, &dev_attr_add_target))
4042
		goto err_class;
4043
	if (device_create_file(&host->dev, &dev_attr_ibdev))
4044
		goto err_class;
4045
	if (device_create_file(&host->dev, &dev_attr_port))
4046 4047 4048 4049 4050
		goto err_class;

	return host;

err_class:
4051
	device_unregister(&host->dev);
4052

4053
free_host:
4054 4055 4056 4057 4058 4059 4060
	kfree(host);

	return NULL;
}

static void srp_add_one(struct ib_device *device)
{
4061
	struct srp_device *srp_dev;
4062
	struct ib_device_attr *attr = &device->attrs;
4063
	struct srp_host *host;
4064
	int mr_page_shift, p;
4065
	u64 max_pages_per_mr;
4066
	unsigned int flags = 0;
4067

4068
	srp_dev = kzalloc(sizeof(*srp_dev), GFP_KERNEL);
4069
	if (!srp_dev)
4070
		return;
4071 4072 4073

	/*
	 * Use the smallest page size supported by the HCA, down to a
4074 4075
	 * minimum of 4096 bytes. We're unlikely to build large sglists
	 * out of smaller entries.
4076
	 */
4077
	mr_page_shift		= max(12, ffs(attr->page_size_cap) - 1);
4078 4079
	srp_dev->mr_page_size	= 1 << mr_page_shift;
	srp_dev->mr_page_mask	= ~((u64) srp_dev->mr_page_size - 1);
4080
	max_pages_per_mr	= attr->max_mr_size;
4081
	do_div(max_pages_per_mr, srp_dev->mr_page_size);
4082
	pr_debug("%s: %llu / %u = %llu <> %u\n", __func__,
4083
		 attr->max_mr_size, srp_dev->mr_page_size,
4084
		 max_pages_per_mr, SRP_MAX_PAGES_PER_MR);
4085 4086
	srp_dev->max_pages_per_mr = min_t(u64, SRP_MAX_PAGES_PER_MR,
					  max_pages_per_mr);
4087 4088 4089

	srp_dev->has_fmr = (device->alloc_fmr && device->dealloc_fmr &&
			    device->map_phys_fmr && device->unmap_fmr);
4090
	srp_dev->has_fr = (attr->device_cap_flags &
4091
			   IB_DEVICE_MEM_MGT_EXTENSIONS);
4092
	if (!never_register && !srp_dev->has_fmr && !srp_dev->has_fr) {
4093
		dev_warn(&device->dev, "neither FMR nor FR is supported\n");
4094
	} else if (!never_register &&
4095
		   attr->max_mr_size >= 2 * srp_dev->mr_page_size) {
4096 4097 4098 4099
		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;
	}
4100

4101 4102 4103 4104
	if (never_register || !register_always ||
	    (!srp_dev->has_fmr && !srp_dev->has_fr))
		flags |= IB_PD_UNSAFE_GLOBAL_RKEY;

4105 4106 4107
	if (srp_dev->use_fast_reg) {
		srp_dev->max_pages_per_mr =
			min_t(u32, srp_dev->max_pages_per_mr,
4108
			      attr->max_fast_reg_page_list_len);
4109
	}
4110 4111
	srp_dev->mr_max_size	= srp_dev->mr_page_size *
				   srp_dev->max_pages_per_mr;
4112
	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",
4113 4114
		 device->name, mr_page_shift, attr->max_mr_size,
		 attr->max_fast_reg_page_list_len,
4115
		 srp_dev->max_pages_per_mr, srp_dev->mr_max_size);
4116 4117 4118 4119

	INIT_LIST_HEAD(&srp_dev->dev_list);

	srp_dev->dev = device;
4120
	srp_dev->pd  = ib_alloc_pd(device, flags);
4121 4122 4123
	if (IS_ERR(srp_dev->pd))
		goto free_dev;

B
Bart Van Assche 已提交
4124 4125 4126 4127
	if (flags & IB_PD_UNSAFE_GLOBAL_RKEY) {
		srp_dev->global_rkey = srp_dev->pd->unsafe_global_rkey;
		WARN_ON_ONCE(srp_dev->global_rkey == 0);
	}
4128

4129
	for (p = rdma_start_port(device); p <= rdma_end_port(device); ++p) {
4130
		host = srp_add_port(srp_dev, p);
4131
		if (host)
4132
			list_add_tail(&host->list, &srp_dev->dev_list);
4133 4134
	}

4135
	ib_set_client_data(device, &srp_client, srp_dev);
4136
	return;
4137 4138 4139

free_dev:
	kfree(srp_dev);
4140 4141
}

4142
static void srp_remove_one(struct ib_device *device, void *client_data)
4143
{
4144
	struct srp_device *srp_dev;
4145
	struct srp_host *host, *tmp_host;
4146
	struct srp_target_port *target;
4147

4148
	srp_dev = client_data;
4149 4150
	if (!srp_dev)
		return;
4151

4152
	list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
4153
		device_unregister(&host->dev);
4154 4155 4156 4157 4158 4159 4160
		/*
		 * Wait for the sysfs entry to go away, so that no new
		 * target ports can be created.
		 */
		wait_for_completion(&host->released);

		/*
4161
		 * Remove all target ports.
4162
		 */
4163
		spin_lock(&host->target_lock);
4164 4165
		list_for_each_entry(target, &host->target_list, list)
			srp_queue_remove_work(target);
4166
		spin_unlock(&host->target_lock);
4167 4168

		/*
4169
		 * Wait for tl_err and target port removal tasks.
4170
		 */
4171
		flush_workqueue(system_long_wq);
4172
		flush_workqueue(srp_remove_wq);
4173 4174 4175 4176

		kfree(host);
	}

4177 4178 4179
	ib_dealloc_pd(srp_dev->pd);

	kfree(srp_dev);
4180 4181
}

4182
static struct srp_function_template ib_srp_transport_functions = {
4183 4184
	.has_rport_state	 = true,
	.reset_timer_if_blocked	 = true,
4185
	.reconnect_delay	 = &srp_reconnect_delay,
4186 4187 4188
	.fast_io_fail_tmo	 = &srp_fast_io_fail_tmo,
	.dev_loss_tmo		 = &srp_dev_loss_tmo,
	.reconnect		 = srp_rport_reconnect,
4189
	.rport_delete		 = srp_rport_delete,
4190
	.terminate_rport_io	 = srp_terminate_io,
4191 4192
};

4193 4194 4195 4196
static int __init srp_init_module(void)
{
	int ret;

4197
	if (srp_sg_tablesize) {
4198
		pr_warn("srp_sg_tablesize is deprecated, please use cmd_sg_entries\n");
4199 4200 4201 4202 4203 4204 4205 4206
		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) {
4207
		pr_warn("Clamping cmd_sg_entries to 255\n");
4208
		cmd_sg_entries = 255;
4209 4210
	}

4211 4212 4213
	if (!indirect_sg_entries)
		indirect_sg_entries = cmd_sg_entries;
	else if (indirect_sg_entries < cmd_sg_entries) {
4214 4215
		pr_warn("Bumping up indirect_sg_entries to match cmd_sg_entries (%u)\n",
			cmd_sg_entries);
4216 4217 4218
		indirect_sg_entries = cmd_sg_entries;
	}

4219 4220 4221 4222 4223 4224
	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;
	}

4225
	srp_remove_wq = create_workqueue("srp_remove");
4226 4227
	if (!srp_remove_wq) {
		ret = -ENOMEM;
4228 4229 4230 4231
		goto out;
	}

	ret = -ENOMEM;
4232 4233 4234
	ib_srp_transport_template =
		srp_attach_transport(&ib_srp_transport_functions);
	if (!ib_srp_transport_template)
4235
		goto destroy_wq;
4236

4237 4238
	ret = class_register(&srp_class);
	if (ret) {
4239
		pr_err("couldn't register class infiniband_srp\n");
4240
		goto release_tr;
4241 4242
	}

4243 4244
	ib_sa_register_client(&srp_sa_client);

4245 4246
	ret = ib_register_client(&srp_client);
	if (ret) {
4247
		pr_err("couldn't register IB client\n");
4248
		goto unreg_sa;
4249 4250
	}

4251 4252 4253 4254 4255 4256 4257 4258 4259 4260 4261 4262 4263
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;
4264 4265 4266 4267 4268
}

static void __exit srp_cleanup_module(void)
{
	ib_unregister_client(&srp_client);
4269
	ib_sa_unregister_client(&srp_sa_client);
4270
	class_unregister(&srp_class);
4271
	srp_release_transport(ib_srp_transport_template);
4272
	destroy_workqueue(srp_remove_wq);
4273 4274 4275 4276
}

module_init(srp_init_module);
module_exit(srp_cleanup_module);