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32 results

sas_expander.c

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  • sas_expander.c 56.74 KiB
    /*
     * Serial Attached SCSI (SAS) Expander discovery and configuration
     *
     * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
     * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
     *
     * This file is licensed under GPLv2.
     *
     * This program is free software; you can redistribute it and/or
     * modify it under the terms of the GNU General Public License as
     * published by the Free Software Foundation; either version 2 of the
     * License, or (at your option) any later version.
     *
     * This program is distributed in the hope that it will be useful, but
     * WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     * General Public License for more details.
     *
     * You should have received a copy of the GNU General Public License
     * along with this program; if not, write to the Free Software
     * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
     *
     */
    
    #include <linux/scatterlist.h>
    #include <linux/blkdev.h>
    #include <linux/slab.h>
    #include <asm/unaligned.h>
    
    #include "sas_internal.h"
    
    #include <scsi/sas_ata.h>
    #include <scsi/scsi_transport.h>
    #include <scsi/scsi_transport_sas.h>
    #include "../scsi_sas_internal.h"
    
    static int sas_discover_expander(struct domain_device *dev);
    static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr);
    static int sas_configure_phy(struct domain_device *dev, int phy_id,
    			     u8 *sas_addr, int include);
    static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr);
    
    /* ---------- SMP task management ---------- */
    
    static void smp_task_timedout(struct timer_list *t)
    {
    	struct sas_task_slow *slow = from_timer(slow, t, timer);
    	struct sas_task *task = slow->task;
    	unsigned long flags;
    
    	spin_lock_irqsave(&task->task_state_lock, flags);
    	if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
    		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
    		complete(&task->slow_task->completion);
    	}
    	spin_unlock_irqrestore(&task->task_state_lock, flags);
    }
    
    static void smp_task_done(struct sas_task *task)
    {
    	del_timer(&task->slow_task->timer);
    	complete(&task->slow_task->completion);
    }
    
    /* Give it some long enough timeout. In seconds. */
    #define SMP_TIMEOUT 10
    
    static int smp_execute_task_sg(struct domain_device *dev,
    		struct scatterlist *req, struct scatterlist *resp)
    {
    	int res, retry;
    	struct sas_task *task = NULL;
    	struct sas_internal *i =
    		to_sas_internal(dev->port->ha->core.shost->transportt);
    
    	mutex_lock(&dev->ex_dev.cmd_mutex);
    	for (retry = 0; retry < 3; retry++) {
    		if (test_bit(SAS_DEV_GONE, &dev->state)) {
    			res = -ECOMM;
    			break;
    		}
    
    		task = sas_alloc_slow_task(GFP_KERNEL);
    		if (!task) {
    			res = -ENOMEM;
    			break;
    		}
    		task->dev = dev;
    		task->task_proto = dev->tproto;
    		task->smp_task.smp_req = *req;
    		task->smp_task.smp_resp = *resp;
    
    		task->task_done = smp_task_done;
    
    		task->slow_task->timer.function = smp_task_timedout;
    		task->slow_task->timer.expires = jiffies + SMP_TIMEOUT*HZ;
    		add_timer(&task->slow_task->timer);
    
    		res = i->dft->lldd_execute_task(task, GFP_KERNEL);
    
    		if (res) {
    			del_timer(&task->slow_task->timer);
    			pr_notice("executing SMP task failed:%d\n", res);
    			break;
    		}
    
    		wait_for_completion(&task->slow_task->completion);
    		res = -ECOMM;
    		if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
    			pr_notice("smp task timed out or aborted\n");
    			i->dft->lldd_abort_task(task);
    			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
    				pr_notice("SMP task aborted and not done\n");
    				break;
    			}
    		}
    		if (task->task_status.resp == SAS_TASK_COMPLETE &&
    		    task->task_status.stat == SAM_STAT_GOOD) {
    			res = 0;
    			break;
    		}
    		if (task->task_status.resp == SAS_TASK_COMPLETE &&
    		    task->task_status.stat == SAS_DATA_UNDERRUN) {
    			/* no error, but return the number of bytes of
    			 * underrun */
    			res = task->task_status.residual;
    			break;
    		}
    		if (task->task_status.resp == SAS_TASK_COMPLETE &&
    		    task->task_status.stat == SAS_DATA_OVERRUN) {
    			res = -EMSGSIZE;
    			break;
    		}
    		if (task->task_status.resp == SAS_TASK_UNDELIVERED &&
    		    task->task_status.stat == SAS_DEVICE_UNKNOWN)
    			break;
    		else {
    			pr_notice("%s: task to dev %016llx response: 0x%x status 0x%x\n",
    				  __func__,
    				  SAS_ADDR(dev->sas_addr),
    				  task->task_status.resp,
    				  task->task_status.stat);
    			sas_free_task(task);
    			task = NULL;
    		}
    	}
    	mutex_unlock(&dev->ex_dev.cmd_mutex);
    
    	BUG_ON(retry == 3 && task != NULL);
    	sas_free_task(task);
    	return res;
    }
    
    static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
    			    void *resp, int resp_size)
    {
    	struct scatterlist req_sg;
    	struct scatterlist resp_sg;
    
    	sg_init_one(&req_sg, req, req_size);
    	sg_init_one(&resp_sg, resp, resp_size);
    	return smp_execute_task_sg(dev, &req_sg, &resp_sg);
    }
    
    /* ---------- Allocations ---------- */
    
    static inline void *alloc_smp_req(int size)
    {
    	u8 *p = kzalloc(size, GFP_KERNEL);
    	if (p)
    		p[0] = SMP_REQUEST;
    	return p;
    }
    
    static inline void *alloc_smp_resp(int size)
    {
    	return kzalloc(size, GFP_KERNEL);
    }
    
    static char sas_route_char(struct domain_device *dev, struct ex_phy *phy)
    {
    	switch (phy->routing_attr) {
    	case TABLE_ROUTING:
    		if (dev->ex_dev.t2t_supp)
    			return 'U';
    		else
    			return 'T';
    	case DIRECT_ROUTING:
    		return 'D';
    	case SUBTRACTIVE_ROUTING:
    		return 'S';
    	default:
    		return '?';
    	}
    }
    
    static enum sas_device_type to_dev_type(struct discover_resp *dr)
    {
    	/* This is detecting a failure to transmit initial dev to host
    	 * FIS as described in section J.5 of sas-2 r16
    	 */
    	if (dr->attached_dev_type == SAS_PHY_UNUSED && dr->attached_sata_dev &&
    	    dr->linkrate >= SAS_LINK_RATE_1_5_GBPS)
    		return SAS_SATA_PENDING;
    	else
    		return dr->attached_dev_type;
    }
    
    static void sas_set_ex_phy(struct domain_device *dev, int phy_id, void *rsp)
    {
    	enum sas_device_type dev_type;
    	enum sas_linkrate linkrate;
    	u8 sas_addr[SAS_ADDR_SIZE];
    	struct smp_resp *resp = rsp;
    	struct discover_resp *dr = &resp->disc;
    	struct sas_ha_struct *ha = dev->port->ha;
    	struct expander_device *ex = &dev->ex_dev;
    	struct ex_phy *phy = &ex->ex_phy[phy_id];
    	struct sas_rphy *rphy = dev->rphy;
    	bool new_phy = !phy->phy;
    	char *type;
    
    	if (new_phy) {
    		if (WARN_ON_ONCE(test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)))
    			return;
    		phy->phy = sas_phy_alloc(&rphy->dev, phy_id);
    
    		/* FIXME: error_handling */
    		BUG_ON(!phy->phy);
    	}
    
    	switch (resp->result) {
    	case SMP_RESP_PHY_VACANT:
    		phy->phy_state = PHY_VACANT;
    		break;
    	default:
    		phy->phy_state = PHY_NOT_PRESENT;
    		break;
    	case SMP_RESP_FUNC_ACC:
    		phy->phy_state = PHY_EMPTY; /* do not know yet */
    		break;
    	}
    
    	/* check if anything important changed to squelch debug */
    	dev_type = phy->attached_dev_type;
    	linkrate  = phy->linkrate;
    	memcpy(sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
    
    	/* Handle vacant phy - rest of dr data is not valid so skip it */
    	if (phy->phy_state == PHY_VACANT) {
    		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
    		phy->attached_dev_type = SAS_PHY_UNUSED;
    		if (!test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
    			phy->phy_id = phy_id;
    			goto skip;
    		} else
    			goto out;
    	}
    
    	phy->attached_dev_type = to_dev_type(dr);
    	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
    		goto out;
    	phy->phy_id = phy_id;
    	phy->linkrate = dr->linkrate;
    	phy->attached_sata_host = dr->attached_sata_host;
    	phy->attached_sata_dev  = dr->attached_sata_dev;
    	phy->attached_sata_ps   = dr->attached_sata_ps;
    	phy->attached_iproto = dr->iproto << 1;
    	phy->attached_tproto = dr->tproto << 1;
    	/* help some expanders that fail to zero sas_address in the 'no
    	 * device' case
    	 */
    	if (phy->attached_dev_type == SAS_PHY_UNUSED ||
    	    phy->linkrate < SAS_LINK_RATE_1_5_GBPS)
    		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
    	else
    		memcpy(phy->attached_sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE);
    	phy->attached_phy_id = dr->attached_phy_id;
    	phy->phy_change_count = dr->change_count;
    	phy->routing_attr = dr->routing_attr;
    	phy->virtual = dr->virtual;
    	phy->last_da_index = -1;
    
    	phy->phy->identify.sas_address = SAS_ADDR(phy->attached_sas_addr);
    	phy->phy->identify.device_type = dr->attached_dev_type;
    	phy->phy->identify.initiator_port_protocols = phy->attached_iproto;
    	phy->phy->identify.target_port_protocols = phy->attached_tproto;
    	if (!phy->attached_tproto && dr->attached_sata_dev)
    		phy->phy->identify.target_port_protocols = SAS_PROTOCOL_SATA;
    	phy->phy->identify.phy_identifier = phy_id;
    	phy->phy->minimum_linkrate_hw = dr->hmin_linkrate;
    	phy->phy->maximum_linkrate_hw = dr->hmax_linkrate;
    	phy->phy->minimum_linkrate = dr->pmin_linkrate;
    	phy->phy->maximum_linkrate = dr->pmax_linkrate;
    	phy->phy->negotiated_linkrate = phy->linkrate;
    	phy->phy->enabled = (phy->linkrate != SAS_PHY_DISABLED);
    
     skip:
    	if (new_phy)
    		if (sas_phy_add(phy->phy)) {
    			sas_phy_free(phy->phy);
    			return;
    		}
    
     out:
    	switch (phy->attached_dev_type) {
    	case SAS_SATA_PENDING:
    		type = "stp pending";
    		break;
    	case SAS_PHY_UNUSED:
    		type = "no device";
    		break;
    	case SAS_END_DEVICE:
    		if (phy->attached_iproto) {
    			if (phy->attached_tproto)
    				type = "host+target";
    			else
    				type = "host";
    		} else {
    			if (dr->attached_sata_dev)
    				type = "stp";
    			else
    				type = "ssp";
    		}
    		break;
    	case SAS_EDGE_EXPANDER_DEVICE:
    	case SAS_FANOUT_EXPANDER_DEVICE:
    		type = "smp";
    		break;
    	default:
    		type = "unknown";
    	}
    
    	/* this routine is polled by libata error recovery so filter
    	 * unimportant messages
    	 */
    	if (new_phy || phy->attached_dev_type != dev_type ||
    	    phy->linkrate != linkrate ||
    	    SAS_ADDR(phy->attached_sas_addr) != SAS_ADDR(sas_addr))
    		/* pass */;
    	else
    		return;
    
    	/* if the attached device type changed and ata_eh is active,
    	 * make sure we run revalidation when eh completes (see:
    	 * sas_enable_revalidation)
    	 */
    	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state))
    		set_bit(DISCE_REVALIDATE_DOMAIN, &dev->port->disc.pending);
    
    	pr_debug("%sex %016llx phy%02d:%c:%X attached: %016llx (%s)\n",
    		 test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state) ? "ata: " : "",
    		 SAS_ADDR(dev->sas_addr), phy->phy_id,
    		 sas_route_char(dev, phy), phy->linkrate,
    		 SAS_ADDR(phy->attached_sas_addr), type);
    }
    
    /* check if we have an existing attached ata device on this expander phy */
    struct domain_device *sas_ex_to_ata(struct domain_device *ex_dev, int phy_id)
    {
    	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy_id];
    	struct domain_device *dev;
    	struct sas_rphy *rphy;
    
    	if (!ex_phy->port)
    		return NULL;
    
    	rphy = ex_phy->port->rphy;
    	if (!rphy)
    		return NULL;
    
    	dev = sas_find_dev_by_rphy(rphy);
    
    	if (dev && dev_is_sata(dev))
    		return dev;
    
    	return NULL;
    }
    
    #define DISCOVER_REQ_SIZE  16
    #define DISCOVER_RESP_SIZE 56
    
    static int sas_ex_phy_discover_helper(struct domain_device *dev, u8 *disc_req,
    				      u8 *disc_resp, int single)
    {
    	struct discover_resp *dr;
    	int res;
    
    	disc_req[9] = single;
    
    	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
    			       disc_resp, DISCOVER_RESP_SIZE);
    	if (res)
    		return res;
    	dr = &((struct smp_resp *)disc_resp)->disc;
    	if (memcmp(dev->sas_addr, dr->attached_sas_addr, SAS_ADDR_SIZE) == 0) {
    		pr_notice("Found loopback topology, just ignore it!\n");
    		return 0;
    	}
    	sas_set_ex_phy(dev, single, disc_resp);
    	return 0;
    }
    
    int sas_ex_phy_discover(struct domain_device *dev, int single)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	int  res = 0;
    	u8   *disc_req;
    	u8   *disc_resp;
    
    	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
    	if (!disc_req)
    		return -ENOMEM;
    
    	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
    	if (!disc_resp) {
    		kfree(disc_req);
    		return -ENOMEM;
    	}
    
    	disc_req[1] = SMP_DISCOVER;
    
    	if (0 <= single && single < ex->num_phys) {
    		res = sas_ex_phy_discover_helper(dev, disc_req, disc_resp, single);
    	} else {
    		int i;
    
    		for (i = 0; i < ex->num_phys; i++) {
    			res = sas_ex_phy_discover_helper(dev, disc_req,
    							 disc_resp, i);
    			if (res)
    				goto out_err;
    		}
    	}
    out_err:
    	kfree(disc_resp);
    	kfree(disc_req);
    	return res;
    }
    
    static int sas_expander_discover(struct domain_device *dev)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	int res = -ENOMEM;
    
    	ex->ex_phy = kcalloc(ex->num_phys, sizeof(*ex->ex_phy), GFP_KERNEL);
    	if (!ex->ex_phy)
    		return -ENOMEM;
    
    	res = sas_ex_phy_discover(dev, -1);
    	if (res)
    		goto out_err;
    
    	return 0;
     out_err:
    	kfree(ex->ex_phy);
    	ex->ex_phy = NULL;
    	return res;
    }
    
    #define MAX_EXPANDER_PHYS 128
    
    static void ex_assign_report_general(struct domain_device *dev,
    					    struct smp_resp *resp)
    {
    	struct report_general_resp *rg = &resp->rg;
    
    	dev->ex_dev.ex_change_count = be16_to_cpu(rg->change_count);
    	dev->ex_dev.max_route_indexes = be16_to_cpu(rg->route_indexes);
    	dev->ex_dev.num_phys = min(rg->num_phys, (u8)MAX_EXPANDER_PHYS);
    	dev->ex_dev.t2t_supp = rg->t2t_supp;
    	dev->ex_dev.conf_route_table = rg->conf_route_table;
    	dev->ex_dev.configuring = rg->configuring;
    	memcpy(dev->ex_dev.enclosure_logical_id, rg->enclosure_logical_id, 8);
    }
    
    #define RG_REQ_SIZE   8
    #define RG_RESP_SIZE 32
    
    static int sas_ex_general(struct domain_device *dev)
    {
    	u8 *rg_req;
    	struct smp_resp *rg_resp;
    	int res;
    	int i;
    
    	rg_req = alloc_smp_req(RG_REQ_SIZE);
    	if (!rg_req)
    		return -ENOMEM;
    
    	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
    	if (!rg_resp) {
    		kfree(rg_req);
    		return -ENOMEM;
    	}
    
    	rg_req[1] = SMP_REPORT_GENERAL;
    
    	for (i = 0; i < 5; i++) {
    		res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
    				       RG_RESP_SIZE);
    
    		if (res) {
    			pr_notice("RG to ex %016llx failed:0x%x\n",
    				  SAS_ADDR(dev->sas_addr), res);
    			goto out;
    		} else if (rg_resp->result != SMP_RESP_FUNC_ACC) {
    			pr_debug("RG:ex %016llx returned SMP result:0x%x\n",
    				 SAS_ADDR(dev->sas_addr), rg_resp->result);
    			res = rg_resp->result;
    			goto out;
    		}
    
    		ex_assign_report_general(dev, rg_resp);
    
    		if (dev->ex_dev.configuring) {
    			pr_debug("RG: ex %llx self-configuring...\n",
    				 SAS_ADDR(dev->sas_addr));
    			schedule_timeout_interruptible(5*HZ);
    		} else
    			break;
    	}
    out:
    	kfree(rg_req);
    	kfree(rg_resp);
    	return res;
    }
    
    static void ex_assign_manuf_info(struct domain_device *dev, void
    					*_mi_resp)
    {
    	u8 *mi_resp = _mi_resp;
    	struct sas_rphy *rphy = dev->rphy;
    	struct sas_expander_device *edev = rphy_to_expander_device(rphy);
    
    	memcpy(edev->vendor_id, mi_resp + 12, SAS_EXPANDER_VENDOR_ID_LEN);
    	memcpy(edev->product_id, mi_resp + 20, SAS_EXPANDER_PRODUCT_ID_LEN);
    	memcpy(edev->product_rev, mi_resp + 36,
    	       SAS_EXPANDER_PRODUCT_REV_LEN);
    
    	if (mi_resp[8] & 1) {
    		memcpy(edev->component_vendor_id, mi_resp + 40,
    		       SAS_EXPANDER_COMPONENT_VENDOR_ID_LEN);
    		edev->component_id = mi_resp[48] << 8 | mi_resp[49];
    		edev->component_revision_id = mi_resp[50];
    	}
    }
    
    #define MI_REQ_SIZE   8
    #define MI_RESP_SIZE 64
    
    static int sas_ex_manuf_info(struct domain_device *dev)
    {
    	u8 *mi_req;
    	u8 *mi_resp;
    	int res;
    
    	mi_req = alloc_smp_req(MI_REQ_SIZE);
    	if (!mi_req)
    		return -ENOMEM;
    
    	mi_resp = alloc_smp_resp(MI_RESP_SIZE);
    	if (!mi_resp) {
    		kfree(mi_req);
    		return -ENOMEM;
    	}
    
    	mi_req[1] = SMP_REPORT_MANUF_INFO;
    
    	res = smp_execute_task(dev, mi_req, MI_REQ_SIZE, mi_resp,MI_RESP_SIZE);
    	if (res) {
    		pr_notice("MI: ex %016llx failed:0x%x\n",
    			  SAS_ADDR(dev->sas_addr), res);
    		goto out;
    	} else if (mi_resp[2] != SMP_RESP_FUNC_ACC) {
    		pr_debug("MI ex %016llx returned SMP result:0x%x\n",
    			 SAS_ADDR(dev->sas_addr), mi_resp[2]);
    		goto out;
    	}
    
    	ex_assign_manuf_info(dev, mi_resp);
    out:
    	kfree(mi_req);
    	kfree(mi_resp);
    	return res;
    }
    
    #define PC_REQ_SIZE  44
    #define PC_RESP_SIZE 8
    
    int sas_smp_phy_control(struct domain_device *dev, int phy_id,
    			enum phy_func phy_func,
    			struct sas_phy_linkrates *rates)
    {
    	u8 *pc_req;
    	u8 *pc_resp;
    	int res;
    
    	pc_req = alloc_smp_req(PC_REQ_SIZE);
    	if (!pc_req)
    		return -ENOMEM;
    
    	pc_resp = alloc_smp_resp(PC_RESP_SIZE);
    	if (!pc_resp) {
    		kfree(pc_req);
    		return -ENOMEM;
    	}
    
    	pc_req[1] = SMP_PHY_CONTROL;
    	pc_req[9] = phy_id;
    	pc_req[10]= phy_func;
    	if (rates) {
    		pc_req[32] = rates->minimum_linkrate << 4;
    		pc_req[33] = rates->maximum_linkrate << 4;
    	}
    
    	res = smp_execute_task(dev, pc_req, PC_REQ_SIZE, pc_resp,PC_RESP_SIZE);
    	if (res) {
    		pr_err("ex %016llx phy%02d PHY control failed: %d\n",
    		       SAS_ADDR(dev->sas_addr), phy_id, res);
    	} else if (pc_resp[2] != SMP_RESP_FUNC_ACC) {
    		pr_err("ex %016llx phy%02d PHY control failed: function result 0x%x\n",
    		       SAS_ADDR(dev->sas_addr), phy_id, pc_resp[2]);
    		res = pc_resp[2];
    	}
    	kfree(pc_resp);
    	kfree(pc_req);
    	return res;
    }
    
    static void sas_ex_disable_phy(struct domain_device *dev, int phy_id)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	struct ex_phy *phy = &ex->ex_phy[phy_id];
    
    	sas_smp_phy_control(dev, phy_id, PHY_FUNC_DISABLE, NULL);
    	phy->linkrate = SAS_PHY_DISABLED;
    }
    
    static void sas_ex_disable_port(struct domain_device *dev, u8 *sas_addr)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	int i;
    
    	for (i = 0; i < ex->num_phys; i++) {
    		struct ex_phy *phy = &ex->ex_phy[i];
    
    		if (phy->phy_state == PHY_VACANT ||
    		    phy->phy_state == PHY_NOT_PRESENT)
    			continue;
    
    		if (SAS_ADDR(phy->attached_sas_addr) == SAS_ADDR(sas_addr))
    			sas_ex_disable_phy(dev, i);
    	}
    }
    
    static int sas_dev_present_in_domain(struct asd_sas_port *port,
    					    u8 *sas_addr)
    {
    	struct domain_device *dev;
    
    	if (SAS_ADDR(port->sas_addr) == SAS_ADDR(sas_addr))
    		return 1;
    	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
    		if (SAS_ADDR(dev->sas_addr) == SAS_ADDR(sas_addr))
    			return 1;
    	}
    	return 0;
    }
    
    #define RPEL_REQ_SIZE	16
    #define RPEL_RESP_SIZE	32
    int sas_smp_get_phy_events(struct sas_phy *phy)
    {
    	int res;
    	u8 *req;
    	u8 *resp;
    	struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
    	struct domain_device *dev = sas_find_dev_by_rphy(rphy);
    
    	req = alloc_smp_req(RPEL_REQ_SIZE);
    	if (!req)
    		return -ENOMEM;
    
    	resp = alloc_smp_resp(RPEL_RESP_SIZE);
    	if (!resp) {
    		kfree(req);
    		return -ENOMEM;
    	}
    
    	req[1] = SMP_REPORT_PHY_ERR_LOG;
    	req[9] = phy->number;
    
    	res = smp_execute_task(dev, req, RPEL_REQ_SIZE,
    			            resp, RPEL_RESP_SIZE);
    
    	if (res)
    		goto out;
    
    	phy->invalid_dword_count = get_unaligned_be32(&resp[12]);
    	phy->running_disparity_error_count = get_unaligned_be32(&resp[16]);
    	phy->loss_of_dword_sync_count = get_unaligned_be32(&resp[20]);
    	phy->phy_reset_problem_count = get_unaligned_be32(&resp[24]);
    
     out:
    	kfree(req);
    	kfree(resp);
    	return res;
    
    }
    
    #ifdef CONFIG_SCSI_SAS_ATA
    
    #define RPS_REQ_SIZE  16
    #define RPS_RESP_SIZE 60
    
    int sas_get_report_phy_sata(struct domain_device *dev, int phy_id,
    			    struct smp_resp *rps_resp)
    {
    	int res;
    	u8 *rps_req = alloc_smp_req(RPS_REQ_SIZE);
    	u8 *resp = (u8 *)rps_resp;
    
    	if (!rps_req)
    		return -ENOMEM;
    
    	rps_req[1] = SMP_REPORT_PHY_SATA;
    	rps_req[9] = phy_id;
    
    	res = smp_execute_task(dev, rps_req, RPS_REQ_SIZE,
    			            rps_resp, RPS_RESP_SIZE);
    
    	/* 0x34 is the FIS type for the D2H fis.  There's a potential
    	 * standards cockup here.  sas-2 explicitly specifies the FIS
    	 * should be encoded so that FIS type is in resp[24].
    	 * However, some expanders endian reverse this.  Undo the
    	 * reversal here */
    	if (!res && resp[27] == 0x34 && resp[24] != 0x34) {
    		int i;
    
    		for (i = 0; i < 5; i++) {
    			int j = 24 + (i*4);
    			u8 a, b;
    			a = resp[j + 0];
    			b = resp[j + 1];
    			resp[j + 0] = resp[j + 3];
    			resp[j + 1] = resp[j + 2];
    			resp[j + 2] = b;
    			resp[j + 3] = a;
    		}
    	}
    
    	kfree(rps_req);
    	return res;
    }
    #endif
    
    static void sas_ex_get_linkrate(struct domain_device *parent,
    				       struct domain_device *child,
    				       struct ex_phy *parent_phy)
    {
    	struct expander_device *parent_ex = &parent->ex_dev;
    	struct sas_port *port;
    	int i;
    
    	child->pathways = 0;
    
    	port = parent_phy->port;
    
    	for (i = 0; i < parent_ex->num_phys; i++) {
    		struct ex_phy *phy = &parent_ex->ex_phy[i];
    
    		if (phy->phy_state == PHY_VACANT ||
    		    phy->phy_state == PHY_NOT_PRESENT)
    			continue;
    
    		if (SAS_ADDR(phy->attached_sas_addr) ==
    		    SAS_ADDR(child->sas_addr)) {
    
    			child->min_linkrate = min(parent->min_linkrate,
    						  phy->linkrate);
    			child->max_linkrate = max(parent->max_linkrate,
    						  phy->linkrate);
    			child->pathways++;
    			sas_port_add_phy(port, phy->phy);
    		}
    	}
    	child->linkrate = min(parent_phy->linkrate, child->max_linkrate);
    	child->pathways = min(child->pathways, parent->pathways);
    }
    
    static struct domain_device *sas_ex_discover_end_dev(
    	struct domain_device *parent, int phy_id)
    {
    	struct expander_device *parent_ex = &parent->ex_dev;
    	struct ex_phy *phy = &parent_ex->ex_phy[phy_id];
    	struct domain_device *child = NULL;
    	struct sas_rphy *rphy;
    	int res;
    
    	if (phy->attached_sata_host || phy->attached_sata_ps)
    		return NULL;
    
    	child = sas_alloc_device();
    	if (!child)
    		return NULL;
    
    	kref_get(&parent->kref);
    	child->parent = parent;
    	child->port   = parent->port;
    	child->iproto = phy->attached_iproto;
    	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
    	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
    	if (!phy->port) {
    		phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
    		if (unlikely(!phy->port))
    			goto out_err;
    		if (unlikely(sas_port_add(phy->port) != 0)) {
    			sas_port_free(phy->port);
    			goto out_err;
    		}
    	}
    	sas_ex_get_linkrate(parent, child, phy);
    	sas_device_set_phy(child, phy->port);
    
    #ifdef CONFIG_SCSI_SAS_ATA
    	if ((phy->attached_tproto & SAS_PROTOCOL_STP) || phy->attached_sata_dev) {
    		if (child->linkrate > parent->min_linkrate) {
    			struct sas_phy *cphy = child->phy;
    			enum sas_linkrate min_prate = cphy->minimum_linkrate,
    				parent_min_lrate = parent->min_linkrate,
    				min_linkrate = (min_prate > parent_min_lrate) ?
    					       parent_min_lrate : 0;
    			struct sas_phy_linkrates rates = {
    				.maximum_linkrate = parent->min_linkrate,
    				.minimum_linkrate = min_linkrate,
    			};
    			int ret;
    
    			pr_notice("ex %016llx phy%02d SATA device linkrate > min pathway connection rate, attempting to lower device linkrate\n",
    				   SAS_ADDR(child->sas_addr), phy_id);
    			ret = sas_smp_phy_control(parent, phy_id,
    						  PHY_FUNC_LINK_RESET, &rates);
    			if (ret) {
    				pr_err("ex %016llx phy%02d SATA device could not set linkrate (%d)\n",
    				       SAS_ADDR(child->sas_addr), phy_id, ret);
    				goto out_free;
    			}
    			pr_notice("ex %016llx phy%02d SATA device set linkrate successfully\n",
    				  SAS_ADDR(child->sas_addr), phy_id);
    			child->linkrate = child->min_linkrate;
    		}
    		res = sas_get_ata_info(child, phy);
    		if (res)
    			goto out_free;
    
    		sas_init_dev(child);
    		res = sas_ata_init(child);
    		if (res)
    			goto out_free;
    		rphy = sas_end_device_alloc(phy->port);
    		if (!rphy)
    			goto out_free;
    		rphy->identify.phy_identifier = phy_id;
    
    		child->rphy = rphy;
    		get_device(&rphy->dev);
    
    		list_add_tail(&child->disco_list_node, &parent->port->disco_list);
    
    		res = sas_discover_sata(child);
    		if (res) {
    			pr_notice("sas_discover_sata() for device %16llx at %016llx:%02d returned 0x%x\n",
    				  SAS_ADDR(child->sas_addr),
    				  SAS_ADDR(parent->sas_addr), phy_id, res);
    			goto out_list_del;
    		}
    	} else
    #endif
    	  if (phy->attached_tproto & SAS_PROTOCOL_SSP) {
    		child->dev_type = SAS_END_DEVICE;
    		rphy = sas_end_device_alloc(phy->port);
    		/* FIXME: error handling */
    		if (unlikely(!rphy))
    			goto out_free;
    		child->tproto = phy->attached_tproto;
    		sas_init_dev(child);
    
    		child->rphy = rphy;
    		get_device(&rphy->dev);
    		rphy->identify.phy_identifier = phy_id;
    		sas_fill_in_rphy(child, rphy);
    
    		list_add_tail(&child->disco_list_node, &parent->port->disco_list);
    
    		res = sas_discover_end_dev(child);
    		if (res) {
    			pr_notice("sas_discover_end_dev() for device %16llx at %016llx:%02d returned 0x%x\n",
    				  SAS_ADDR(child->sas_addr),
    				  SAS_ADDR(parent->sas_addr), phy_id, res);
    			goto out_list_del;
    		}
    	} else {
    		pr_notice("target proto 0x%x at %016llx:0x%x not handled\n",
    			  phy->attached_tproto, SAS_ADDR(parent->sas_addr),
    			  phy_id);
    		goto out_free;
    	}
    
    	list_add_tail(&child->siblings, &parent_ex->children);
    	return child;
    
     out_list_del:
    	sas_rphy_free(child->rphy);
    	list_del(&child->disco_list_node);
    	spin_lock_irq(&parent->port->dev_list_lock);
    	list_del(&child->dev_list_node);
    	spin_unlock_irq(&parent->port->dev_list_lock);
     out_free:
    	sas_port_delete(phy->port);
     out_err:
    	phy->port = NULL;
    	sas_put_device(child);
    	return NULL;
    }
    
    /* See if this phy is part of a wide port */
    static bool sas_ex_join_wide_port(struct domain_device *parent, int phy_id)
    {
    	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
    	int i;
    
    	for (i = 0; i < parent->ex_dev.num_phys; i++) {
    		struct ex_phy *ephy = &parent->ex_dev.ex_phy[i];
    
    		if (ephy == phy)
    			continue;
    
    		if (!memcmp(phy->attached_sas_addr, ephy->attached_sas_addr,
    			    SAS_ADDR_SIZE) && ephy->port) {
    			sas_port_add_phy(ephy->port, phy->phy);
    			phy->port = ephy->port;
    			phy->phy_state = PHY_DEVICE_DISCOVERED;
    			return true;
    		}
    	}
    
    	return false;
    }
    
    static struct domain_device *sas_ex_discover_expander(
    	struct domain_device *parent, int phy_id)
    {
    	struct sas_expander_device *parent_ex = rphy_to_expander_device(parent->rphy);
    	struct ex_phy *phy = &parent->ex_dev.ex_phy[phy_id];
    	struct domain_device *child = NULL;
    	struct sas_rphy *rphy;
    	struct sas_expander_device *edev;
    	struct asd_sas_port *port;
    	int res;
    
    	if (phy->routing_attr == DIRECT_ROUTING) {
    		pr_warn("ex %016llx:%02d:D <--> ex %016llx:0x%x is not allowed\n",
    			SAS_ADDR(parent->sas_addr), phy_id,
    			SAS_ADDR(phy->attached_sas_addr),
    			phy->attached_phy_id);
    		return NULL;
    	}
    	child = sas_alloc_device();
    	if (!child)
    		return NULL;
    
    	phy->port = sas_port_alloc(&parent->rphy->dev, phy_id);
    	/* FIXME: better error handling */
    	BUG_ON(sas_port_add(phy->port) != 0);
    
    
    	switch (phy->attached_dev_type) {
    	case SAS_EDGE_EXPANDER_DEVICE:
    		rphy = sas_expander_alloc(phy->port,
    					  SAS_EDGE_EXPANDER_DEVICE);
    		break;
    	case SAS_FANOUT_EXPANDER_DEVICE:
    		rphy = sas_expander_alloc(phy->port,
    					  SAS_FANOUT_EXPANDER_DEVICE);
    		break;
    	default:
    		rphy = NULL;	/* shut gcc up */
    		BUG();
    	}
    	port = parent->port;
    	child->rphy = rphy;
    	get_device(&rphy->dev);
    	edev = rphy_to_expander_device(rphy);
    	child->dev_type = phy->attached_dev_type;
    	kref_get(&parent->kref);
    	child->parent = parent;
    	child->port = port;
    	child->iproto = phy->attached_iproto;
    	child->tproto = phy->attached_tproto;
    	memcpy(child->sas_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
    	sas_hash_addr(child->hashed_sas_addr, child->sas_addr);
    	sas_ex_get_linkrate(parent, child, phy);
    	edev->level = parent_ex->level + 1;
    	parent->port->disc.max_level = max(parent->port->disc.max_level,
    					   edev->level);
    	sas_init_dev(child);
    	sas_fill_in_rphy(child, rphy);
    	sas_rphy_add(rphy);
    
    	spin_lock_irq(&parent->port->dev_list_lock);
    	list_add_tail(&child->dev_list_node, &parent->port->dev_list);
    	spin_unlock_irq(&parent->port->dev_list_lock);
    
    	res = sas_discover_expander(child);
    	if (res) {
    		sas_rphy_delete(rphy);
    		spin_lock_irq(&parent->port->dev_list_lock);
    		list_del(&child->dev_list_node);
    		spin_unlock_irq(&parent->port->dev_list_lock);
    		sas_put_device(child);
    		sas_port_delete(phy->port);
    		phy->port = NULL;
    		return NULL;
    	}
    	list_add_tail(&child->siblings, &parent->ex_dev.children);
    	return child;
    }
    
    static int sas_ex_discover_dev(struct domain_device *dev, int phy_id)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
    	struct domain_device *child = NULL;
    	int res = 0;
    
    	/* Phy state */
    	if (ex_phy->linkrate == SAS_SATA_SPINUP_HOLD) {
    		if (!sas_smp_phy_control(dev, phy_id, PHY_FUNC_LINK_RESET, NULL))
    			res = sas_ex_phy_discover(dev, phy_id);
    		if (res)
    			return res;
    	}
    
    	/* Parent and domain coherency */
    	if (!dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
    			     SAS_ADDR(dev->port->sas_addr))) {
    		sas_add_parent_port(dev, phy_id);
    		return 0;
    	}
    	if (dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
    			    SAS_ADDR(dev->parent->sas_addr))) {
    		sas_add_parent_port(dev, phy_id);
    		if (ex_phy->routing_attr == TABLE_ROUTING)
    			sas_configure_phy(dev, phy_id, dev->port->sas_addr, 1);
    		return 0;
    	}
    
    	if (sas_dev_present_in_domain(dev->port, ex_phy->attached_sas_addr))
    		sas_ex_disable_port(dev, ex_phy->attached_sas_addr);
    
    	if (ex_phy->attached_dev_type == SAS_PHY_UNUSED) {
    		if (ex_phy->routing_attr == DIRECT_ROUTING) {
    			memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
    			sas_configure_routing(dev, ex_phy->attached_sas_addr);
    		}
    		return 0;
    	} else if (ex_phy->linkrate == SAS_LINK_RATE_UNKNOWN)
    		return 0;
    
    	if (ex_phy->attached_dev_type != SAS_END_DEVICE &&
    	    ex_phy->attached_dev_type != SAS_FANOUT_EXPANDER_DEVICE &&
    	    ex_phy->attached_dev_type != SAS_EDGE_EXPANDER_DEVICE &&
    	    ex_phy->attached_dev_type != SAS_SATA_PENDING) {
    		pr_warn("unknown device type(0x%x) attached to ex %016llx phy%02d\n",
    			ex_phy->attached_dev_type,
    			SAS_ADDR(dev->sas_addr),
    			phy_id);
    		return 0;
    	}
    
    	res = sas_configure_routing(dev, ex_phy->attached_sas_addr);
    	if (res) {
    		pr_notice("configure routing for dev %016llx reported 0x%x. Forgotten\n",
    			  SAS_ADDR(ex_phy->attached_sas_addr), res);
    		sas_disable_routing(dev, ex_phy->attached_sas_addr);
    		return res;
    	}
    
    	if (sas_ex_join_wide_port(dev, phy_id)) {
    		pr_debug("Attaching ex phy%02d to wide port %016llx\n",
    			 phy_id, SAS_ADDR(ex_phy->attached_sas_addr));
    		return res;
    	}
    
    	switch (ex_phy->attached_dev_type) {
    	case SAS_END_DEVICE:
    	case SAS_SATA_PENDING:
    		child = sas_ex_discover_end_dev(dev, phy_id);
    		break;
    	case SAS_FANOUT_EXPANDER_DEVICE:
    		if (SAS_ADDR(dev->port->disc.fanout_sas_addr)) {
    			pr_debug("second fanout expander %016llx phy%02d attached to ex %016llx phy%02d\n",
    				 SAS_ADDR(ex_phy->attached_sas_addr),
    				 ex_phy->attached_phy_id,
    				 SAS_ADDR(dev->sas_addr),
    				 phy_id);
    			sas_ex_disable_phy(dev, phy_id);
    			break;
    		} else
    			memcpy(dev->port->disc.fanout_sas_addr,
    			       ex_phy->attached_sas_addr, SAS_ADDR_SIZE);
    		/* fallthrough */
    	case SAS_EDGE_EXPANDER_DEVICE:
    		child = sas_ex_discover_expander(dev, phy_id);
    		break;
    	default:
    		break;
    	}
    
    	if (child) {
    		int i;
    
    		for (i = 0; i < ex->num_phys; i++) {
    			if (ex->ex_phy[i].phy_state == PHY_VACANT ||
    			    ex->ex_phy[i].phy_state == PHY_NOT_PRESENT)
    				continue;
    			/*
    			 * Due to races, the phy might not get added to the
    			 * wide port, so we add the phy to the wide port here.
    			 */
    			if (SAS_ADDR(ex->ex_phy[i].attached_sas_addr) ==
    			    SAS_ADDR(child->sas_addr)) {
    				ex->ex_phy[i].phy_state= PHY_DEVICE_DISCOVERED;
    				if (sas_ex_join_wide_port(dev, i))
    					pr_debug("Attaching ex phy%02d to wide port %016llx\n",
    						 i, SAS_ADDR(ex->ex_phy[i].attached_sas_addr));
    			}
    		}
    	}
    
    	return res;
    }
    
    static int sas_find_sub_addr(struct domain_device *dev, u8 *sub_addr)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	int i;
    
    	for (i = 0; i < ex->num_phys; i++) {
    		struct ex_phy *phy = &ex->ex_phy[i];
    
    		if (phy->phy_state == PHY_VACANT ||
    		    phy->phy_state == PHY_NOT_PRESENT)
    			continue;
    
    		if ((phy->attached_dev_type == SAS_EDGE_EXPANDER_DEVICE ||
    		     phy->attached_dev_type == SAS_FANOUT_EXPANDER_DEVICE) &&
    		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
    
    			memcpy(sub_addr, phy->attached_sas_addr, SAS_ADDR_SIZE);
    
    			return 1;
    		}
    	}
    	return 0;
    }
    
    static int sas_check_level_subtractive_boundary(struct domain_device *dev)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	struct domain_device *child;
    	u8 sub_addr[SAS_ADDR_SIZE] = {0, };
    
    	list_for_each_entry(child, &ex->children, siblings) {
    		if (child->dev_type != SAS_EDGE_EXPANDER_DEVICE &&
    		    child->dev_type != SAS_FANOUT_EXPANDER_DEVICE)
    			continue;
    		if (sub_addr[0] == 0) {
    			sas_find_sub_addr(child, sub_addr);
    			continue;
    		} else {
    			u8 s2[SAS_ADDR_SIZE];
    
    			if (sas_find_sub_addr(child, s2) &&
    			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
    
    				pr_notice("ex %016llx->%016llx-?->%016llx diverges from subtractive boundary %016llx\n",
    					  SAS_ADDR(dev->sas_addr),
    					  SAS_ADDR(child->sas_addr),
    					  SAS_ADDR(s2),
    					  SAS_ADDR(sub_addr));
    
    				sas_ex_disable_port(child, s2);
    			}
    		}
    	}
    	return 0;
    }
    /**
     * sas_ex_discover_devices - discover devices attached to this expander
     * @dev: pointer to the expander domain device
     * @single: if you want to do a single phy, else set to -1;
     *
     * Configure this expander for use with its devices and register the
     * devices of this expander.
     */
    static int sas_ex_discover_devices(struct domain_device *dev, int single)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	int i = 0, end = ex->num_phys;
    	int res = 0;
    
    	if (0 <= single && single < end) {
    		i = single;
    		end = i+1;
    	}
    
    	for ( ; i < end; i++) {
    		struct ex_phy *ex_phy = &ex->ex_phy[i];
    
    		if (ex_phy->phy_state == PHY_VACANT ||
    		    ex_phy->phy_state == PHY_NOT_PRESENT ||
    		    ex_phy->phy_state == PHY_DEVICE_DISCOVERED)
    			continue;
    
    		switch (ex_phy->linkrate) {
    		case SAS_PHY_DISABLED:
    		case SAS_PHY_RESET_PROBLEM:
    		case SAS_SATA_PORT_SELECTOR:
    			continue;
    		default:
    			res = sas_ex_discover_dev(dev, i);
    			if (res)
    				break;
    			continue;
    		}
    	}
    
    	if (!res)
    		sas_check_level_subtractive_boundary(dev);
    
    	return res;
    }
    
    static int sas_check_ex_subtractive_boundary(struct domain_device *dev)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	int i;
    	u8  *sub_sas_addr = NULL;
    
    	if (dev->dev_type != SAS_EDGE_EXPANDER_DEVICE)
    		return 0;
    
    	for (i = 0; i < ex->num_phys; i++) {
    		struct ex_phy *phy = &ex->ex_phy[i];
    
    		if (phy->phy_state == PHY_VACANT ||
    		    phy->phy_state == PHY_NOT_PRESENT)
    			continue;
    
    		if ((phy->attached_dev_type == SAS_FANOUT_EXPANDER_DEVICE ||
    		     phy->attached_dev_type == SAS_EDGE_EXPANDER_DEVICE) &&
    		    phy->routing_attr == SUBTRACTIVE_ROUTING) {
    
    			if (!sub_sas_addr)
    				sub_sas_addr = &phy->attached_sas_addr[0];
    			else if (SAS_ADDR(sub_sas_addr) !=
    				 SAS_ADDR(phy->attached_sas_addr)) {
    
    				pr_notice("ex %016llx phy%02d diverges(%016llx) on subtractive boundary(%016llx). Disabled\n",
    					  SAS_ADDR(dev->sas_addr), i,
    					  SAS_ADDR(phy->attached_sas_addr),
    					  SAS_ADDR(sub_sas_addr));
    				sas_ex_disable_phy(dev, i);
    			}
    		}
    	}
    	return 0;
    }
    
    static void sas_print_parent_topology_bug(struct domain_device *child,
    						 struct ex_phy *parent_phy,
    						 struct ex_phy *child_phy)
    {
    	static const char *ex_type[] = {
    		[SAS_EDGE_EXPANDER_DEVICE] = "edge",
    		[SAS_FANOUT_EXPANDER_DEVICE] = "fanout",
    	};
    	struct domain_device *parent = child->parent;
    
    	pr_notice("%s ex %016llx phy%02d <--> %s ex %016llx phy%02d has %c:%c routing link!\n",
    		  ex_type[parent->dev_type],
    		  SAS_ADDR(parent->sas_addr),
    		  parent_phy->phy_id,
    
    		  ex_type[child->dev_type],
    		  SAS_ADDR(child->sas_addr),
    		  child_phy->phy_id,
    
    		  sas_route_char(parent, parent_phy),
    		  sas_route_char(child, child_phy));
    }
    
    static int sas_check_eeds(struct domain_device *child,
    				 struct ex_phy *parent_phy,
    				 struct ex_phy *child_phy)
    {
    	int res = 0;
    	struct domain_device *parent = child->parent;
    
    	if (SAS_ADDR(parent->port->disc.fanout_sas_addr) != 0) {
    		res = -ENODEV;
    		pr_warn("edge ex %016llx phy S:%02d <--> edge ex %016llx phy S:%02d, while there is a fanout ex %016llx\n",
    			SAS_ADDR(parent->sas_addr),
    			parent_phy->phy_id,
    			SAS_ADDR(child->sas_addr),
    			child_phy->phy_id,
    			SAS_ADDR(parent->port->disc.fanout_sas_addr));
    	} else if (SAS_ADDR(parent->port->disc.eeds_a) == 0) {
    		memcpy(parent->port->disc.eeds_a, parent->sas_addr,
    		       SAS_ADDR_SIZE);
    		memcpy(parent->port->disc.eeds_b, child->sas_addr,
    		       SAS_ADDR_SIZE);
    	} else if (((SAS_ADDR(parent->port->disc.eeds_a) ==
    		    SAS_ADDR(parent->sas_addr)) ||
    		   (SAS_ADDR(parent->port->disc.eeds_a) ==
    		    SAS_ADDR(child->sas_addr)))
    		   &&
    		   ((SAS_ADDR(parent->port->disc.eeds_b) ==
    		     SAS_ADDR(parent->sas_addr)) ||
    		    (SAS_ADDR(parent->port->disc.eeds_b) ==
    		     SAS_ADDR(child->sas_addr))))
    		;
    	else {
    		res = -ENODEV;
    		pr_warn("edge ex %016llx phy%02d <--> edge ex %016llx phy%02d link forms a third EEDS!\n",
    			SAS_ADDR(parent->sas_addr),
    			parent_phy->phy_id,
    			SAS_ADDR(child->sas_addr),
    			child_phy->phy_id);
    	}
    
    	return res;
    }
    
    /* Here we spill over 80 columns.  It is intentional.
     */
    static int sas_check_parent_topology(struct domain_device *child)
    {
    	struct expander_device *child_ex = &child->ex_dev;
    	struct expander_device *parent_ex;
    	int i;
    	int res = 0;
    
    	if (!child->parent)
    		return 0;
    
    	if (child->parent->dev_type != SAS_EDGE_EXPANDER_DEVICE &&
    	    child->parent->dev_type != SAS_FANOUT_EXPANDER_DEVICE)
    		return 0;
    
    	parent_ex = &child->parent->ex_dev;
    
    	for (i = 0; i < parent_ex->num_phys; i++) {
    		struct ex_phy *parent_phy = &parent_ex->ex_phy[i];
    		struct ex_phy *child_phy;
    
    		if (parent_phy->phy_state == PHY_VACANT ||
    		    parent_phy->phy_state == PHY_NOT_PRESENT)
    			continue;
    
    		if (SAS_ADDR(parent_phy->attached_sas_addr) != SAS_ADDR(child->sas_addr))
    			continue;
    
    		child_phy = &child_ex->ex_phy[parent_phy->attached_phy_id];
    
    		switch (child->parent->dev_type) {
    		case SAS_EDGE_EXPANDER_DEVICE:
    			if (child->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
    				if (parent_phy->routing_attr != SUBTRACTIVE_ROUTING ||
    				    child_phy->routing_attr != TABLE_ROUTING) {
    					sas_print_parent_topology_bug(child, parent_phy, child_phy);
    					res = -ENODEV;
    				}
    			} else if (parent_phy->routing_attr == SUBTRACTIVE_ROUTING) {
    				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING) {
    					res = sas_check_eeds(child, parent_phy, child_phy);
    				} else if (child_phy->routing_attr != TABLE_ROUTING) {
    					sas_print_parent_topology_bug(child, parent_phy, child_phy);
    					res = -ENODEV;
    				}
    			} else if (parent_phy->routing_attr == TABLE_ROUTING) {
    				if (child_phy->routing_attr == SUBTRACTIVE_ROUTING ||
    				    (child_phy->routing_attr == TABLE_ROUTING &&
    				     child_ex->t2t_supp && parent_ex->t2t_supp)) {
    					/* All good */;
    				} else {
    					sas_print_parent_topology_bug(child, parent_phy, child_phy);
    					res = -ENODEV;
    				}
    			}
    			break;
    		case SAS_FANOUT_EXPANDER_DEVICE:
    			if (parent_phy->routing_attr != TABLE_ROUTING ||
    			    child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
    				sas_print_parent_topology_bug(child, parent_phy, child_phy);
    				res = -ENODEV;
    			}
    			break;
    		default:
    			break;
    		}
    	}
    
    	return res;
    }
    
    #define RRI_REQ_SIZE  16
    #define RRI_RESP_SIZE 44
    
    static int sas_configure_present(struct domain_device *dev, int phy_id,
    				 u8 *sas_addr, int *index, int *present)
    {
    	int i, res = 0;
    	struct expander_device *ex = &dev->ex_dev;
    	struct ex_phy *phy = &ex->ex_phy[phy_id];
    	u8 *rri_req;
    	u8 *rri_resp;
    
    	*present = 0;
    	*index = 0;
    
    	rri_req = alloc_smp_req(RRI_REQ_SIZE);
    	if (!rri_req)
    		return -ENOMEM;
    
    	rri_resp = alloc_smp_resp(RRI_RESP_SIZE);
    	if (!rri_resp) {
    		kfree(rri_req);
    		return -ENOMEM;
    	}
    
    	rri_req[1] = SMP_REPORT_ROUTE_INFO;
    	rri_req[9] = phy_id;
    
    	for (i = 0; i < ex->max_route_indexes ; i++) {
    		*(__be16 *)(rri_req+6) = cpu_to_be16(i);
    		res = smp_execute_task(dev, rri_req, RRI_REQ_SIZE, rri_resp,
    				       RRI_RESP_SIZE);
    		if (res)
    			goto out;
    		res = rri_resp[2];
    		if (res == SMP_RESP_NO_INDEX) {
    			pr_warn("overflow of indexes: dev %016llx phy%02d index 0x%x\n",
    				SAS_ADDR(dev->sas_addr), phy_id, i);
    			goto out;
    		} else if (res != SMP_RESP_FUNC_ACC) {
    			pr_notice("%s: dev %016llx phy%02d index 0x%x result 0x%x\n",
    				  __func__, SAS_ADDR(dev->sas_addr), phy_id,
    				  i, res);
    			goto out;
    		}
    		if (SAS_ADDR(sas_addr) != 0) {
    			if (SAS_ADDR(rri_resp+16) == SAS_ADDR(sas_addr)) {
    				*index = i;
    				if ((rri_resp[12] & 0x80) == 0x80)
    					*present = 0;
    				else
    					*present = 1;
    				goto out;
    			} else if (SAS_ADDR(rri_resp+16) == 0) {
    				*index = i;
    				*present = 0;
    				goto out;
    			}
    		} else if (SAS_ADDR(rri_resp+16) == 0 &&
    			   phy->last_da_index < i) {
    			phy->last_da_index = i;
    			*index = i;
    			*present = 0;
    			goto out;
    		}
    	}
    	res = -1;
    out:
    	kfree(rri_req);
    	kfree(rri_resp);
    	return res;
    }
    
    #define CRI_REQ_SIZE  44
    #define CRI_RESP_SIZE  8
    
    static int sas_configure_set(struct domain_device *dev, int phy_id,
    			     u8 *sas_addr, int index, int include)
    {
    	int res;
    	u8 *cri_req;
    	u8 *cri_resp;
    
    	cri_req = alloc_smp_req(CRI_REQ_SIZE);
    	if (!cri_req)
    		return -ENOMEM;
    
    	cri_resp = alloc_smp_resp(CRI_RESP_SIZE);
    	if (!cri_resp) {
    		kfree(cri_req);
    		return -ENOMEM;
    	}
    
    	cri_req[1] = SMP_CONF_ROUTE_INFO;
    	*(__be16 *)(cri_req+6) = cpu_to_be16(index);
    	cri_req[9] = phy_id;
    	if (SAS_ADDR(sas_addr) == 0 || !include)
    		cri_req[12] |= 0x80;
    	memcpy(cri_req+16, sas_addr, SAS_ADDR_SIZE);
    
    	res = smp_execute_task(dev, cri_req, CRI_REQ_SIZE, cri_resp,
    			       CRI_RESP_SIZE);
    	if (res)
    		goto out;
    	res = cri_resp[2];
    	if (res == SMP_RESP_NO_INDEX) {
    		pr_warn("overflow of indexes: dev %016llx phy%02d index 0x%x\n",
    			SAS_ADDR(dev->sas_addr), phy_id, index);
    	}
    out:
    	kfree(cri_req);
    	kfree(cri_resp);
    	return res;
    }
    
    static int sas_configure_phy(struct domain_device *dev, int phy_id,
    				    u8 *sas_addr, int include)
    {
    	int index;
    	int present;
    	int res;
    
    	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
    	if (res)
    		return res;
    	if (include ^ present)
    		return sas_configure_set(dev, phy_id, sas_addr, index,include);
    
    	return res;
    }
    
    /**
     * sas_configure_parent - configure routing table of parent
     * @parent: parent expander
     * @child: child expander
     * @sas_addr: SAS port identifier of device directly attached to child
     * @include: whether or not to include @child in the expander routing table
     */
    static int sas_configure_parent(struct domain_device *parent,
    				struct domain_device *child,
    				u8 *sas_addr, int include)
    {
    	struct expander_device *ex_parent = &parent->ex_dev;
    	int res = 0;
    	int i;
    
    	if (parent->parent) {
    		res = sas_configure_parent(parent->parent, parent, sas_addr,
    					   include);
    		if (res)
    			return res;
    	}
    
    	if (ex_parent->conf_route_table == 0) {
    		pr_debug("ex %016llx has self-configuring routing table\n",
    			 SAS_ADDR(parent->sas_addr));
    		return 0;
    	}
    
    	for (i = 0; i < ex_parent->num_phys; i++) {
    		struct ex_phy *phy = &ex_parent->ex_phy[i];
    
    		if ((phy->routing_attr == TABLE_ROUTING) &&
    		    (SAS_ADDR(phy->attached_sas_addr) ==
    		     SAS_ADDR(child->sas_addr))) {
    			res = sas_configure_phy(parent, i, sas_addr, include);
    			if (res)
    				return res;
    		}
    	}
    
    	return res;
    }
    
    /**
     * sas_configure_routing - configure routing
     * @dev: expander device
     * @sas_addr: port identifier of device directly attached to the expander device
     */
    static int sas_configure_routing(struct domain_device *dev, u8 *sas_addr)
    {
    	if (dev->parent)
    		return sas_configure_parent(dev->parent, dev, sas_addr, 1);
    	return 0;
    }
    
    static int sas_disable_routing(struct domain_device *dev,  u8 *sas_addr)
    {
    	if (dev->parent)
    		return sas_configure_parent(dev->parent, dev, sas_addr, 0);
    	return 0;
    }
    
    /**
     * sas_discover_expander - expander discovery
     * @dev: pointer to expander domain device
     *
     * See comment in sas_discover_sata().
     */
    static int sas_discover_expander(struct domain_device *dev)
    {
    	int res;
    
    	res = sas_notify_lldd_dev_found(dev);
    	if (res)
    		return res;
    
    	res = sas_ex_general(dev);
    	if (res)
    		goto out_err;
    	res = sas_ex_manuf_info(dev);
    	if (res)
    		goto out_err;
    
    	res = sas_expander_discover(dev);
    	if (res) {
    		pr_warn("expander %016llx discovery failed(0x%x)\n",
    			SAS_ADDR(dev->sas_addr), res);
    		goto out_err;
    	}
    
    	sas_check_ex_subtractive_boundary(dev);
    	res = sas_check_parent_topology(dev);
    	if (res)
    		goto out_err;
    	return 0;
    out_err:
    	sas_notify_lldd_dev_gone(dev);
    	return res;
    }
    
    static int sas_ex_level_discovery(struct asd_sas_port *port, const int level)
    {
    	int res = 0;
    	struct domain_device *dev;
    
    	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
    		if (dev->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
    		    dev->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
    			struct sas_expander_device *ex =
    				rphy_to_expander_device(dev->rphy);
    
    			if (level == ex->level)
    				res = sas_ex_discover_devices(dev, -1);
    			else if (level > 0)
    				res = sas_ex_discover_devices(port->port_dev, -1);
    
    		}
    	}
    
    	return res;
    }
    
    static int sas_ex_bfs_disc(struct asd_sas_port *port)
    {
    	int res;
    	int level;
    
    	do {
    		level = port->disc.max_level;
    		res = sas_ex_level_discovery(port, level);
    		mb();
    	} while (level < port->disc.max_level);
    
    	return res;
    }
    
    int sas_discover_root_expander(struct domain_device *dev)
    {
    	int res;
    	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
    
    	res = sas_rphy_add(dev->rphy);
    	if (res)
    		goto out_err;
    
    	ex->level = dev->port->disc.max_level; /* 0 */
    	res = sas_discover_expander(dev);
    	if (res)
    		goto out_err2;
    
    	sas_ex_bfs_disc(dev->port);
    
    	return res;
    
    out_err2:
    	sas_rphy_remove(dev->rphy);
    out_err:
    	return res;
    }
    
    /* ---------- Domain revalidation ---------- */
    
    static int sas_get_phy_discover(struct domain_device *dev,
    				int phy_id, struct smp_resp *disc_resp)
    {
    	int res;
    	u8 *disc_req;
    
    	disc_req = alloc_smp_req(DISCOVER_REQ_SIZE);
    	if (!disc_req)
    		return -ENOMEM;
    
    	disc_req[1] = SMP_DISCOVER;
    	disc_req[9] = phy_id;
    
    	res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
    			       disc_resp, DISCOVER_RESP_SIZE);
    	if (res)
    		goto out;
    	else if (disc_resp->result != SMP_RESP_FUNC_ACC) {
    		res = disc_resp->result;
    		goto out;
    	}
    out:
    	kfree(disc_req);
    	return res;
    }
    
    static int sas_get_phy_change_count(struct domain_device *dev,
    				    int phy_id, int *pcc)
    {
    	int res;
    	struct smp_resp *disc_resp;
    
    	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
    	if (!disc_resp)
    		return -ENOMEM;
    
    	res = sas_get_phy_discover(dev, phy_id, disc_resp);
    	if (!res)
    		*pcc = disc_resp->disc.change_count;
    
    	kfree(disc_resp);
    	return res;
    }
    
    static int sas_get_phy_attached_dev(struct domain_device *dev, int phy_id,
    				    u8 *sas_addr, enum sas_device_type *type)
    {
    	int res;
    	struct smp_resp *disc_resp;
    	struct discover_resp *dr;
    
    	disc_resp = alloc_smp_resp(DISCOVER_RESP_SIZE);
    	if (!disc_resp)
    		return -ENOMEM;
    	dr = &disc_resp->disc;
    
    	res = sas_get_phy_discover(dev, phy_id, disc_resp);
    	if (res == 0) {
    		memcpy(sas_addr, disc_resp->disc.attached_sas_addr,
    		       SAS_ADDR_SIZE);
    		*type = to_dev_type(dr);
    		if (*type == 0)
    			memset(sas_addr, 0, SAS_ADDR_SIZE);
    	}
    	kfree(disc_resp);
    	return res;
    }
    
    static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
    			      int from_phy, bool update)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	int res = 0;
    	int i;
    
    	for (i = from_phy; i < ex->num_phys; i++) {
    		int phy_change_count = 0;
    
    		res = sas_get_phy_change_count(dev, i, &phy_change_count);
    		switch (res) {
    		case SMP_RESP_PHY_VACANT:
    		case SMP_RESP_NO_PHY:
    			continue;
    		case SMP_RESP_FUNC_ACC:
    			break;
    		default:
    			return res;
    		}
    
    		if (phy_change_count != ex->ex_phy[i].phy_change_count) {
    			if (update)
    				ex->ex_phy[i].phy_change_count =
    					phy_change_count;
    			*phy_id = i;
    			return 0;
    		}
    	}
    	return 0;
    }
    
    static int sas_get_ex_change_count(struct domain_device *dev, int *ecc)
    {
    	int res;
    	u8  *rg_req;
    	struct smp_resp  *rg_resp;
    
    	rg_req = alloc_smp_req(RG_REQ_SIZE);
    	if (!rg_req)
    		return -ENOMEM;
    
    	rg_resp = alloc_smp_resp(RG_RESP_SIZE);
    	if (!rg_resp) {
    		kfree(rg_req);
    		return -ENOMEM;
    	}
    
    	rg_req[1] = SMP_REPORT_GENERAL;
    
    	res = smp_execute_task(dev, rg_req, RG_REQ_SIZE, rg_resp,
    			       RG_RESP_SIZE);
    	if (res)
    		goto out;
    	if (rg_resp->result != SMP_RESP_FUNC_ACC) {
    		res = rg_resp->result;
    		goto out;
    	}
    
    	*ecc = be16_to_cpu(rg_resp->rg.change_count);
    out:
    	kfree(rg_resp);
    	kfree(rg_req);
    	return res;
    }
    /**
     * sas_find_bcast_dev -  find the device issue BROADCAST(CHANGE).
     * @dev:domain device to be detect.
     * @src_dev: the device which originated BROADCAST(CHANGE).
     *
     * Add self-configuration expander support. Suppose two expander cascading,
     * when the first level expander is self-configuring, hotplug the disks in
     * second level expander, BROADCAST(CHANGE) will not only be originated
     * in the second level expander, but also be originated in the first level
     * expander (see SAS protocol SAS 2r-14, 7.11 for detail), it is to say,
     * expander changed count in two level expanders will all increment at least
     * once, but the phy which chang count has changed is the source device which
     * we concerned.
     */
    
    static int sas_find_bcast_dev(struct domain_device *dev,
    			      struct domain_device **src_dev)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	int ex_change_count = -1;
    	int phy_id = -1;
    	int res;
    	struct domain_device *ch;
    
    	res = sas_get_ex_change_count(dev, &ex_change_count);
    	if (res)
    		goto out;
    	if (ex_change_count != -1 && ex_change_count != ex->ex_change_count) {
    		/* Just detect if this expander phys phy change count changed,
    		* in order to determine if this expander originate BROADCAST,
    		* and do not update phy change count field in our structure.
    		*/
    		res = sas_find_bcast_phy(dev, &phy_id, 0, false);
    		if (phy_id != -1) {
    			*src_dev = dev;
    			ex->ex_change_count = ex_change_count;
    			pr_info("ex %016llx phy%02d change count has changed\n",
    				SAS_ADDR(dev->sas_addr), phy_id);
    			return res;
    		} else
    			pr_info("ex %016llx phys DID NOT change\n",
    				SAS_ADDR(dev->sas_addr));
    	}
    	list_for_each_entry(ch, &ex->children, siblings) {
    		if (ch->dev_type == SAS_EDGE_EXPANDER_DEVICE || ch->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
    			res = sas_find_bcast_dev(ch, src_dev);
    			if (*src_dev)
    				return res;
    		}
    	}
    out:
    	return res;
    }
    
    static void sas_unregister_ex_tree(struct asd_sas_port *port, struct domain_device *dev)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	struct domain_device *child, *n;
    
    	list_for_each_entry_safe(child, n, &ex->children, siblings) {
    		set_bit(SAS_DEV_GONE, &child->state);
    		if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
    		    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
    			sas_unregister_ex_tree(port, child);
    		else
    			sas_unregister_dev(port, child);
    	}
    	sas_unregister_dev(port, dev);
    }
    
    static void sas_unregister_devs_sas_addr(struct domain_device *parent,
    					 int phy_id, bool last)
    {
    	struct expander_device *ex_dev = &parent->ex_dev;
    	struct ex_phy *phy = &ex_dev->ex_phy[phy_id];
    	struct domain_device *child, *n, *found = NULL;
    	if (last) {
    		list_for_each_entry_safe(child, n,
    			&ex_dev->children, siblings) {
    			if (SAS_ADDR(child->sas_addr) ==
    			    SAS_ADDR(phy->attached_sas_addr)) {
    				set_bit(SAS_DEV_GONE, &child->state);
    				if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
    				    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
    					sas_unregister_ex_tree(parent->port, child);
    				else
    					sas_unregister_dev(parent->port, child);
    				found = child;
    				break;
    			}
    		}
    		sas_disable_routing(parent, phy->attached_sas_addr);
    	}
    	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
    	if (phy->port) {
    		sas_port_delete_phy(phy->port, phy->phy);
    		sas_device_set_phy(found, phy->port);
    		if (phy->port->num_phys == 0)
    			list_add_tail(&phy->port->del_list,
    				&parent->port->sas_port_del_list);
    		phy->port = NULL;
    	}
    }
    
    static int sas_discover_bfs_by_root_level(struct domain_device *root,
    					  const int level)
    {
    	struct expander_device *ex_root = &root->ex_dev;
    	struct domain_device *child;
    	int res = 0;
    
    	list_for_each_entry(child, &ex_root->children, siblings) {
    		if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
    		    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
    			struct sas_expander_device *ex =
    				rphy_to_expander_device(child->rphy);
    
    			if (level > ex->level)
    				res = sas_discover_bfs_by_root_level(child,
    								     level);
    			else if (level == ex->level)
    				res = sas_ex_discover_devices(child, -1);
    		}
    	}
    	return res;
    }
    
    static int sas_discover_bfs_by_root(struct domain_device *dev)
    {
    	int res;
    	struct sas_expander_device *ex = rphy_to_expander_device(dev->rphy);
    	int level = ex->level+1;
    
    	res = sas_ex_discover_devices(dev, -1);
    	if (res)
    		goto out;
    	do {
    		res = sas_discover_bfs_by_root_level(dev, level);
    		mb();
    		level += 1;
    	} while (level <= dev->port->disc.max_level);
    out:
    	return res;
    }
    
    static int sas_discover_new(struct domain_device *dev, int phy_id)
    {
    	struct ex_phy *ex_phy = &dev->ex_dev.ex_phy[phy_id];
    	struct domain_device *child;
    	int res;
    
    	pr_debug("ex %016llx phy%02d new device attached\n",
    		 SAS_ADDR(dev->sas_addr), phy_id);
    	res = sas_ex_phy_discover(dev, phy_id);
    	if (res)
    		return res;
    
    	if (sas_ex_join_wide_port(dev, phy_id))
    		return 0;
    
    	res = sas_ex_discover_devices(dev, phy_id);
    	if (res)
    		return res;
    	list_for_each_entry(child, &dev->ex_dev.children, siblings) {
    		if (SAS_ADDR(child->sas_addr) ==
    		    SAS_ADDR(ex_phy->attached_sas_addr)) {
    			if (child->dev_type == SAS_EDGE_EXPANDER_DEVICE ||
    			    child->dev_type == SAS_FANOUT_EXPANDER_DEVICE)
    				res = sas_discover_bfs_by_root(child);
    			break;
    		}
    	}
    	return res;
    }
    
    static bool dev_type_flutter(enum sas_device_type new, enum sas_device_type old)
    {
    	if (old == new)
    		return true;
    
    	/* treat device directed resets as flutter, if we went
    	 * SAS_END_DEVICE to SAS_SATA_PENDING the link needs recovery
    	 */
    	if ((old == SAS_SATA_PENDING && new == SAS_END_DEVICE) ||
    	    (old == SAS_END_DEVICE && new == SAS_SATA_PENDING))
    		return true;
    
    	return false;
    }
    
    static int sas_rediscover_dev(struct domain_device *dev, int phy_id,
    			      bool last, int sibling)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	struct ex_phy *phy = &ex->ex_phy[phy_id];
    	enum sas_device_type type = SAS_PHY_UNUSED;
    	u8 sas_addr[SAS_ADDR_SIZE];
    	char msg[80] = "";
    	int res;
    
    	if (!last)
    		sprintf(msg, ", part of a wide port with phy%02d", sibling);
    
    	pr_debug("ex %016llx rediscovering phy%02d%s\n",
    		 SAS_ADDR(dev->sas_addr), phy_id, msg);
    
    	memset(sas_addr, 0, SAS_ADDR_SIZE);
    	res = sas_get_phy_attached_dev(dev, phy_id, sas_addr, &type);
    	switch (res) {
    	case SMP_RESP_NO_PHY:
    		phy->phy_state = PHY_NOT_PRESENT;
    		sas_unregister_devs_sas_addr(dev, phy_id, last);
    		return res;
    	case SMP_RESP_PHY_VACANT:
    		phy->phy_state = PHY_VACANT;
    		sas_unregister_devs_sas_addr(dev, phy_id, last);
    		return res;
    	case SMP_RESP_FUNC_ACC:
    		break;
    	case -ECOMM:
    		break;
    	default:
    		return res;
    	}
    
    	if ((SAS_ADDR(sas_addr) == 0) || (res == -ECOMM)) {
    		phy->phy_state = PHY_EMPTY;
    		sas_unregister_devs_sas_addr(dev, phy_id, last);
    		/*
    		 * Even though the PHY is empty, for convenience we discover
    		 * the PHY to update the PHY info, like negotiated linkrate.
    		 */
    		sas_ex_phy_discover(dev, phy_id);
    		return res;
    	} else if (SAS_ADDR(sas_addr) == SAS_ADDR(phy->attached_sas_addr) &&
    		   dev_type_flutter(type, phy->attached_dev_type)) {
    		struct domain_device *ata_dev = sas_ex_to_ata(dev, phy_id);
    		char *action = "";
    
    		sas_ex_phy_discover(dev, phy_id);
    
    		if (ata_dev && phy->attached_dev_type == SAS_SATA_PENDING)
    			action = ", needs recovery";
    		pr_debug("ex %016llx phy%02d broadcast flutter%s\n",
    			 SAS_ADDR(dev->sas_addr), phy_id, action);
    		return res;
    	}
    
    	/* we always have to delete the old device when we went here */
    	pr_info("ex %016llx phy%02d replace %016llx\n",
    		SAS_ADDR(dev->sas_addr), phy_id,
    		SAS_ADDR(phy->attached_sas_addr));
    	sas_unregister_devs_sas_addr(dev, phy_id, last);
    
    	return sas_discover_new(dev, phy_id);
    }
    
    /**
     * sas_rediscover - revalidate the domain.
     * @dev:domain device to be detect.
     * @phy_id: the phy id will be detected.
     *
     * NOTE: this process _must_ quit (return) as soon as any connection
     * errors are encountered.  Connection recovery is done elsewhere.
     * Discover process only interrogates devices in order to discover the
     * domain.For plugging out, we un-register the device only when it is
     * the last phy in the port, for other phys in this port, we just delete it
     * from the port.For inserting, we do discovery when it is the
     * first phy,for other phys in this port, we add it to the port to
     * forming the wide-port.
     */
    static int sas_rediscover(struct domain_device *dev, const int phy_id)
    {
    	struct expander_device *ex = &dev->ex_dev;
    	struct ex_phy *changed_phy = &ex->ex_phy[phy_id];
    	int res = 0;
    	int i;
    	bool last = true;	/* is this the last phy of the port */
    
    	pr_debug("ex %016llx phy%02d originated BROADCAST(CHANGE)\n",
    		 SAS_ADDR(dev->sas_addr), phy_id);
    
    	if (SAS_ADDR(changed_phy->attached_sas_addr) != 0) {
    		for (i = 0; i < ex->num_phys; i++) {
    			struct ex_phy *phy = &ex->ex_phy[i];
    
    			if (i == phy_id)
    				continue;
    			if (SAS_ADDR(phy->attached_sas_addr) ==
    			    SAS_ADDR(changed_phy->attached_sas_addr)) {
    				last = false;
    				break;
    			}
    		}
    		res = sas_rediscover_dev(dev, phy_id, last, i);
    	} else
    		res = sas_discover_new(dev, phy_id);
    	return res;
    }
    
    /**
     * sas_ex_revalidate_domain - revalidate the domain
     * @port_dev: port domain device.
     *
     * NOTE: this process _must_ quit (return) as soon as any connection
     * errors are encountered.  Connection recovery is done elsewhere.
     * Discover process only interrogates devices in order to discover the
     * domain.
     */
    int sas_ex_revalidate_domain(struct domain_device *port_dev)
    {
    	int res;
    	struct domain_device *dev = NULL;
    
    	res = sas_find_bcast_dev(port_dev, &dev);
    	if (res == 0 && dev) {
    		struct expander_device *ex = &dev->ex_dev;
    		int i = 0, phy_id;
    
    		do {
    			phy_id = -1;
    			res = sas_find_bcast_phy(dev, &phy_id, i, true);
    			if (phy_id == -1)
    				break;
    			res = sas_rediscover(dev, phy_id);
    			i = phy_id + 1;
    		} while (i < ex->num_phys);
    	}
    	return res;
    }
    
    void sas_smp_handler(struct bsg_job *job, struct Scsi_Host *shost,
    		struct sas_rphy *rphy)
    {
    	struct domain_device *dev;
    	unsigned int rcvlen = 0;
    	int ret = -EINVAL;
    
    	/* no rphy means no smp target support (ie aic94xx host) */
    	if (!rphy)
    		return sas_smp_host_handler(job, shost);
    
    	switch (rphy->identify.device_type) {
    	case SAS_EDGE_EXPANDER_DEVICE:
    	case SAS_FANOUT_EXPANDER_DEVICE:
    		break;
    	default:
    		pr_err("%s: can we send a smp request to a device?\n",
    		       __func__);
    		goto out;
    	}
    
    	dev = sas_find_dev_by_rphy(rphy);
    	if (!dev) {
    		pr_err("%s: fail to find a domain_device?\n", __func__);
    		goto out;
    	}
    
    	/* do we need to support multiple segments? */
    	if (job->request_payload.sg_cnt > 1 ||
    	    job->reply_payload.sg_cnt > 1) {
    		pr_info("%s: multiple segments req %u, rsp %u\n",
    			__func__, job->request_payload.payload_len,
    			job->reply_payload.payload_len);
    		goto out;
    	}
    
    	ret = smp_execute_task_sg(dev, job->request_payload.sg_list,
    			job->reply_payload.sg_list);
    	if (ret >= 0) {
    		/* bsg_job_done() requires the length received  */
    		rcvlen = job->reply_payload.payload_len - ret;
    		ret = 0;
    	}
    
    out:
    	bsg_job_done(job, ret, rcvlen);
    }