sas-class: sas_expander.c Expander discovery and configuration

diff -X linux-2.6.13/Documentation/dontdiff -Naur linux-2.6.13-orig/drivers/scsi/sas-class/sas_expander.c linux-2.6.13/drivers/scsi/sas-class/sas_expander.c
@@ -0,0 +1,1830 @@
+/*
+ * Serial Attached SCSI (SAS) Expander discovery and configuration
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <[email protected]>
+ *
+ * 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
+ *
+ * $Id: //depot/sas-class/sas_expander.c#54 $
+ */
+
+#include <linux/pci.h>
+#include <linux/scatterlist.h>
+
+#include "sas_internal.h"
+#include <scsi/sas/sas_task.h>
+#include <scsi/sas/sas_discover.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_disable_routing(struct domain_device *dev,  u8 *sas_addr);
+
+static ssize_t smp_portal_read(struct kobject *, char *, loff_t, size_t);
+static ssize_t smp_portal_write(struct kobject *, char *, loff_t, size_t);
+
+/* ---------- Expander attributes ---------- */
+
+static ssize_t ex_show_change_count(struct domain_device *dev, char *page)
+{
+	return sprintf(page, "%d\n", dev->ex_dev.ex_change_count);
+}
+
+static ssize_t ex_show_max_route_indexes(struct domain_device *dev, char *page)
+{
+	return sprintf(page, "%d\n", dev->ex_dev.max_route_indexes);
+}
+
+static ssize_t ex_show_num_phys(struct domain_device *dev, char *page)
+{
+	return sprintf(page, "%d\n", dev->ex_dev.num_phys);
+}
+
+static ssize_t ex_show_enclosure_logical_id(struct domain_device *dev,
+					    char *page)
+{
+	return sprintf(page, "%llx\n",
+		       SAS_ADDR(dev->ex_dev.enclosure_logical_id));
+}
+
+static ssize_t ex_show_vendor_id(struct domain_device *dev, char *page)
+{
+	return sprintf(page, "%s\n", dev->ex_dev.vendor_id);
+}
+
+static ssize_t ex_show_product_id(struct domain_device *dev, char *page)
+{
+	return sprintf(page, "%s\n", dev->ex_dev.product_id);
+}
+
+static ssize_t ex_show_product_rev(struct domain_device *dev, char *page)
+{
+	return sprintf(page, "%s\n", dev->ex_dev.product_rev);
+}
+
+static ssize_t ex_show_component_vendor_id(struct domain_device *dev,
+					   char *page)
+{
+	return sprintf(page, "%s\n", dev->ex_dev.component_vendor_id);
+}
+
+static ssize_t ex_show_component_id(struct domain_device *dev, char *page)
+{
+	return sprintf(page, "%d\n", dev->ex_dev.component_id);
+}
+
+static ssize_t ex_show_component_revision_id(struct domain_device *dev,
+					     char *page)
+{
+	return sprintf(page, "%d\n", dev->ex_dev.component_revision_id);
+}
+
+static ssize_t ex_show_conf_route_table(struct domain_device *dev,
+					char *page)
+{
+	return sprintf(page, "%d\n", dev->ex_dev.conf_route_table);
+}
+
+static ssize_t ex_show_configuring(struct domain_device *dev,
+				   char *page)
+{
+	return sprintf(page, "%d\n", dev->ex_dev.configuring);
+}
+
+static struct domain_dev_attribute ex_attrs[] = {
+	__ATTR(dev_type, 0444, dev_show_type, NULL),
+	__ATTR(iproto, 0444, dev_show_iproto, NULL),
+	__ATTR(tproto, 0444, dev_show_tproto, NULL),
+	__ATTR(sas_addr, 0444, dev_show_sas_addr, NULL),
+	__ATTR(linkrate, 0444, dev_show_linkrate, NULL),
+	__ATTR(min_linkrate, 0444, dev_show_min_linkrate, NULL),
+	__ATTR(max_linkrate, 0444, dev_show_max_linkrate, NULL),
+	__ATTR(pathways, 0444, dev_show_pathways, NULL),
+	__ATTR(change_count, 0444, ex_show_change_count, NULL),
+	__ATTR(max_route_indexes, 0444, ex_show_max_route_indexes, NULL),
+	__ATTR(num_phys, 0444, ex_show_num_phys, NULL),
+	__ATTR(enclosure_logical_id, 0444, ex_show_enclosure_logical_id, NULL),
+	__ATTR(vendor_id, 0444, ex_show_vendor_id, NULL),
+	__ATTR(product_id, 0444, ex_show_product_id, NULL),
+	__ATTR(product_rev, 0444, ex_show_product_rev, NULL),
+	__ATTR(component_vendor_id, 0444, ex_show_component_vendor_id, NULL),
+	__ATTR(component_id, 0444, ex_show_component_id, NULL),
+	__ATTR(component_revision_id, 0444,ex_show_component_revision_id,NULL),
+	__ATTR(conf_route_table, 0444, ex_show_conf_route_table, NULL),
+	__ATTR(configuring, 0444, ex_show_configuring, NULL),
+	__ATTR_NULL,
+};
+
+static struct attribute *ex_dev_attrs[ARRAY_SIZE(ex_attrs)];
+
+static void ex_dev_release(struct kobject *obj)
+{
+	struct domain_device *dev = to_dom_device(obj);
+	SAS_DPRINTK("freeing dev %016llx\n", SAS_ADDR(dev->sas_addr));
+	kfree(dev->ex_dev.ex_phy);
+	kfree(dev->ex_dev.smp_req);
+	kfree(dev);
+}
+
+struct kobj_type ex_dev_ktype = {
+	.release = ex_dev_release,
+	.sysfs_ops = &dev_sysfs_ops,
+	.default_attrs = ex_dev_attrs,
+};
+
+/* ---------- SMP task management ---------- */
+
+static void smp_task_timedout(unsigned long _task)
+{
+	struct sas_task *task = (void *) _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;
+	spin_unlock_irqrestore(&task->task_state_lock, flags);
+	
+	complete(&task->completion);
+}
+
+static void smp_task_done(struct sas_task *task)
+{
+	if (!del_timer(&task->timer))
+		return;
+	complete(&task->completion);
+}
+
+/* Give it some long enough timeout. In seconds. */
+#define SMP_TIMEOUT 10
+
+static int smp_execute_task(struct domain_device *dev, void *req, int req_size,
+			    void *resp, int resp_size)
+{
+	int res;
+	struct sas_task *task = sas_alloc_task(GFP_KERNEL);
+
+	if (!task)
+		return -ENOMEM;
+
+	task->dev = dev;
+	task->task_proto = dev->tproto;
+	sg_init_one(&task->smp_task.smp_req, req, req_size);
+	sg_init_one(&task->smp_task.smp_resp, resp, resp_size);
+
+	task->task_done = smp_task_done;
+
+	task->timer.data = (unsigned long) task;
+	task->timer.function = smp_task_timedout;
+	task->timer.expires = jiffies + SMP_TIMEOUT*HZ;
+	add_timer(&task->timer);
+
+	res = task->dev->port->ha->lldd_execute_task(task, 1, GFP_KERNEL);
+
+	if (res) {
+		del_timer(&task->timer);
+		SAS_DPRINTK("executing SMP task failed:%d\n", res);
+		goto ex_err;
+	}
+
+	wait_for_completion(&task->completion);
+	res = -ETASK;
+	if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
+		SAS_DPRINTK("smp task timed out or aborted\n");
+		task->dev->port->ha->lldd_abort_task(task);
+		if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
+			SAS_DPRINTK("SMP task aborted and not done\n");
+			goto ex_err;
+		}
+	}
+	if (task->task_status.resp == SAS_TASK_COMPLETE &&
+	    task->task_status.stat == SAM_GOOD)
+		res = 0;
+	else
+		SAS_DPRINTK("%s: task to dev %016llx response: 0x%x "
+			    "status 0x%x\n", __FUNCTION__,
+			    SAS_ADDR(dev->sas_addr),
+			    task->task_status.resp,
+			    task->task_status.stat);
+ex_err:	
+	sas_free_task(task);
+	return res;
+}
+
+/* ---------- Allocations ---------- */ 
+
+static inline void *alloc_smp_req(int size)
+{
+	u8 *p = kmalloc(size, GFP_KERNEL);
+	if (p) {
+		memset(p, 0, size);
+		p[0] = SMP_REQUEST;
+	}
+	return p;
+}
+
+static inline void *alloc_smp_resp(int size)
+{
+	u8 *p = kmalloc(size, GFP_KERNEL);
+	if (p)
+		memset(p, 0, size);
+	return p;
+}
+
+/* ---------- Expander configuration ---------- */
+
+static void sas_set_ex_phy(struct domain_device *dev, int phy_id,
+			   void *disc_resp)
+{
+	struct expander_device *ex = &dev->ex_dev;
+	struct ex_phy *phy = &ex->ex_phy[phy_id];
+	struct smp_resp *resp = disc_resp;
+	struct discover_resp *dr = &resp->disc;
+
+	switch (resp->result) {
+	case SMP_RESP_PHY_VACANT:
+		phy->phy_state = PHY_VACANT;
+		return;
+	default:
+		phy->phy_state = PHY_NOT_PRESENT;
+		return;
+	case SMP_RESP_FUNC_ACC:
+		phy->phy_state = PHY_EMPTY; /* do not know yet */
+		break;
+	}
+
+	phy->phy_id = phy_id;
+	phy->attached_dev_type = dr->attached_dev_type;
+	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;
+	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;
+
+	SAS_DPRINTK("ex %016llx phy%02d:%c attached: %016llx\n",
+		    SAS_ADDR(dev->sas_addr), phy->phy_id,
+		    phy->routing_attr == TABLE_ROUTING ? 'T' :
+		    phy->routing_attr == DIRECT_ROUTING ? 'D' :
+		    phy->routing_attr == SUBTRACTIVE_ROUTING ? 'S' : '?',
+		    SAS_ADDR(phy->attached_sas_addr));
+
+	return;
+}
+
+#define DISCOVER_REQ_SIZE  16
+#define DISCOVER_RESP_SIZE 56
+
+static 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_req(DISCOVER_RESP_SIZE);
+	if (!disc_resp) {
+		kfree(disc_req);
+		return -ENOMEM;
+	}
+
+	disc_req[1] = SMP_DISCOVER;
+
+	if (0 <= single && single < ex->num_phys) {
+		disc_req[9] = single;
+		res = smp_execute_task(dev, disc_req, DISCOVER_REQ_SIZE,
+				       disc_resp, DISCOVER_RESP_SIZE);
+		if (res)
+			goto out_err;
+		sas_set_ex_phy(dev, single, disc_resp);
+	} else {
+		int i;
+
+		for (i = 0; i < ex->num_phys; i++) {
+			disc_req[9] = i;
+			res = smp_execute_task(dev, disc_req,
+					       DISCOVER_REQ_SIZE, disc_resp,
+					       DISCOVER_RESP_SIZE);
+			if (res)
+				goto out_err;
+			sas_set_ex_phy(dev, i, disc_resp);
+		}
+	}
+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;
+
+	ex->ex_phy = kmalloc(sizeof(*ex->ex_phy)*ex->num_phys, GFP_KERNEL);
+	if (!ex->ex_phy)
+		return -ENOMEM;
+	memset(ex->ex_phy, 0, sizeof(*ex->ex_phy)*ex->num_phys);
+	
+	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 inline 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.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) {
+			SAS_DPRINTK("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) {
+			SAS_DPRINTK("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) {
+			SAS_DPRINTK("RG: ex %llx self-configuring...\n",
+				    SAS_ADDR(dev->sas_addr));
+			set_current_state(TASK_INTERRUPTIBLE);
+			schedule_timeout(5*HZ);
+		} else
+			break;
+	}
+out:	
+	kfree(rg_req);
+	kfree(rg_resp);
+	return res;
+}
+
+static inline void ex_assign_manuf_info(struct domain_device *dev, void
+					*_mi_resp)
+{
+	u8 *mi_resp = _mi_resp;
+
+	memcpy(dev->ex_dev.vendor_id, mi_resp + 12, 8);
+	memcpy(dev->ex_dev.product_id, mi_resp + 20, 16);
+	memcpy(dev->ex_dev.product_rev, mi_resp + 36, 4);
+
+	if (mi_resp[8] & 1) {
+		memcpy(dev->ex_dev.component_vendor_id, mi_resp + 40, 8);
+		dev->ex_dev.component_id =
+			be16_to_cpu(*(__be16 *)(mi_resp + 48));
+		dev->ex_dev.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) {
+		SAS_DPRINTK("MI: ex %016llx failed:0x%x\n",
+			    SAS_ADDR(dev->sas_addr), res);
+		goto out;
+	} else if (mi_resp[2] != SMP_RESP_FUNC_ACC) {
+		SAS_DPRINTK("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
+
+static int smp_phy_control(struct domain_device *dev, int phy_id,
+			   enum phy_func phy_func)
+{
+	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;
+
+	res = smp_execute_task(dev, pc_req, PC_REQ_SIZE, pc_resp,PC_RESP_SIZE);
+	
+	kfree(pc_resp);
+	kfree(pc_req);
+	return res;
+}
+
+static inline 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];
+
+	smp_phy_control(dev, phy_id, PHY_FUNC_DISABLE);
+	phy->linkrate = PHY_DISABLED;
+}
+
+static inline 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 inline int sas_dev_present_in_domain(struct 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 RPS_REQ_SIZE  16
+#define RPS_RESP_SIZE 60
+
+static inline 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);
+
+	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);
+
+	kfree(rps_req);
+	return 0;
+}
+
+static inline 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;
+	int i;
+
+	child->pathways = 0;
+
+	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++;
+		}
+	}
+	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;
+	int res;
+
+	if (phy->attached_sata_host || phy->attached_sata_ps)
+		return NULL;
+
+	child = kmalloc(sizeof(*child), GFP_KERNEL);
+	if (!child)
+		return NULL;
+	memset(child, 0, sizeof(*child));
+
+	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);
+	sas_ex_get_linkrate(parent, child, phy);
+
+	if ((phy->attached_tproto & SAS_PROTO_STP) || phy->attached_sata_dev) {
+		child->dev_type = SATA_DEV;
+		if (phy->attached_tproto & SAS_PROTO_STP)
+			child->tproto = phy->attached_tproto;
+		if (phy->attached_sata_dev)
+			child->tproto |= SATA_DEV;
+		res = sas_get_report_phy_sata(parent, phy_id,
+					      &child->sata_dev.rps_resp);
+		if (res) {
+			SAS_DPRINTK("report phy sata to %016llx:0x%x returned "
+				    "0x%x\n", SAS_ADDR(parent->sas_addr),
+				    phy_id, res);
+			kfree(child);
+			return NULL;
+		}
+		memcpy(child->frame_rcvd, &child->sata_dev.rps_resp.rps.fis,
+		       sizeof(struct dev_to_host_fis));
+		sas_init_dev(child);
+		res = sas_discover_sata(child);
+		if (res) {
+			SAS_DPRINTK("sas_discover_sata() for device %16llx at "
+				    "%016llx:0x%x returned 0x%x\n",
+				    SAS_ADDR(child->sas_addr),
+				    SAS_ADDR(parent->sas_addr), phy_id, res);
+			kfree(child);
+			return NULL;
+		}
+	} else if (phy->attached_tproto & SAS_PROTO_SSP) {
+		child->dev_type = SAS_END_DEV;
+		child->tproto = phy->attached_tproto;
+		sas_init_dev(child);
+		res = sas_discover_end_dev(child);
+		if (res) {
+			SAS_DPRINTK("sas_discover_end_dev() for device %16llx "
+				    "at %016llx:0x%x returned 0x%x\n",
+				    SAS_ADDR(child->sas_addr),
+				    SAS_ADDR(parent->sas_addr), phy_id, res);
+			kfree(child);
+			return NULL;
+		}
+	} else {
+		SAS_DPRINTK("target proto 0x%x at %016llx:0x%x not handled\n",
+			    phy->attached_tproto, SAS_ADDR(parent->sas_addr),
+			    phy_id);
+	}
+	list_add_tail(&child->siblings, &parent_ex->children);
+	return child;
+}
+
+static struct domain_device *sas_ex_discover_expander(
+	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;
+	int res;
+
+	if (phy->routing_attr == DIRECT_ROUTING) {
+		SAS_DPRINTK("ex %016llx:0x%x: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 = kmalloc(sizeof(*child), GFP_KERNEL);
+	if (!child)
+		return NULL;
+	memset(child, 0, sizeof(*child));
+	child->dev_type = phy->attached_dev_type;
+	child->parent = parent;
+	child->port = parent->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);
+	child->ex_dev.level = parent_ex->level + 1;
+	parent->port->disc.max_level = max(parent->port->disc.max_level,
+					   child->ex_dev.level);
+	sas_init_dev(child);
+	res = sas_discover_expander(child);
+	if (res) {
+		kfree(child);
+		return NULL;
+	}		
+	list_add_tail(&child->siblings, &parent_ex->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 == PHY_SPINUP_HOLD) {
+		if (!smp_phy_control(dev, phy_id, PHY_FUNC_LINK_RESET))
+			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)))
+		return 0;
+	if (dev->parent && (SAS_ADDR(ex_phy->attached_sas_addr) ==
+			    SAS_ADDR(dev->parent->sas_addr)))
+		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 == NO_DEVICE) {
+		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 == PHY_LINKRATE_UNKNOWN)
+		return 0;
+	
+	if (ex_phy->attached_dev_type != SAS_END_DEV &&
+	    ex_phy->attached_dev_type != FANOUT_DEV &&
+	    ex_phy->attached_dev_type != EDGE_DEV) {
+		SAS_DPRINTK("unknown device type(0x%x) attached to ex %016llx "
+			    "phy 0x%x\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) {
+		SAS_DPRINTK("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;
+	}
+
+	switch (ex_phy->attached_dev_type) {
+	case SAS_END_DEV:
+		child = sas_ex_discover_end_dev(dev, phy_id);
+		break;
+	case FANOUT_DEV:
+		if (SAS_ADDR(dev->port->disc.fanout_sas_addr)) {
+			SAS_DPRINTK("second fanout expander %016llx phy 0x%x "
+				    "attached to ex %016llx phy 0x%x\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 EDGE_DEV:
+		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;
+			
+			if (SAS_ADDR(ex->ex_phy[i].attached_sas_addr) ==
+			    SAS_ADDR(child->sas_addr))
+				ex->ex_phy[i].phy_state= PHY_DEVICE_DISCOVERED;
+		}
+	}
+
+	return res;
+}
+
+static inline 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 == EDGE_DEV ||
+		     phy->attached_dev_type == FANOUT_DEV) &&
+		    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[8] = {0, };
+
+	list_for_each_entry(child, &ex->children, siblings) {
+		if (child->dev_type != EDGE_DEV &&
+		    child->dev_type != FANOUT_DEV)
+			continue;
+		if (sub_addr[0] == 0) {
+			sas_find_sub_addr(child, sub_addr);
+			continue;
+		} else {
+			u8 s2[8];
+
+			if (sas_find_sub_addr(child, s2) &&
+			    (SAS_ADDR(sub_addr) != SAS_ADDR(s2))) {
+
+				SAS_DPRINTK("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 PHY_DISABLED:
+		case PHY_RESET_PROBLEM:
+		case PHY_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 != EDGE_DEV)
+		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 == FANOUT_DEV ||
+		     phy->attached_dev_type == EDGE_DEV) &&
+		    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)) {
+
+				SAS_DPRINTK("ex %016llx phy 0x%x "
+					    "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 inline void sas_print_parent_topology_bug(struct domain_device *child,
+						 struct ex_phy *parent_phy,
+						 struct ex_phy *child_phy)
+{
+	static const char ra_char[] = {
+		[DIRECT_ROUTING] = 'D',
+		[SUBTRACTIVE_ROUTING] = 'S',
+		[TABLE_ROUTING] = 'T',
+	};
+	static const char *ex_type[] = {
+		[EDGE_DEV] = "edge",
+		[FANOUT_DEV] = "fanout",
+	};
+	struct domain_device *parent = child->parent;
+
+	sas_printk("%s ex %016llx phy 0x%x <--> %s ex %016llx phy 0x%x "
+		   "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,
+
+		   ra_char[parent_phy->routing_attr],
+		   ra_char[child_phy->routing_attr]);
+}
+
+static inline 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;
+		SAS_DPRINTK("edge ex %016llx phy S:0x%x <--> edge ex %016llx "
+			    "phy S:0x%x, 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;
+		SAS_DPRINTK("edge ex %016llx phy 0x%x <--> edge ex %016llx "
+			    "phy 0x%x 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 != EDGE_DEV &&
+	    child->parent->dev_type != FANOUT_DEV)
+		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 EDGE_DEV:
+			if (child->dev_type == FANOUT_DEV) {
+				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 &&
+				   child_phy->routing_attr != SUBTRACTIVE_ROUTING) {
+				sas_print_parent_topology_bug(child, parent_phy, child_phy);
+				res = -ENODEV;
+			}
+			break;
+		case FANOUT_DEV:
+			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) {
+			SAS_DPRINTK("overflow of indexes: dev %016llx "
+				    "phy 0x%x index 0x%x\n",
+				    SAS_ADDR(dev->sas_addr), phy_id, i);
+			goto out;
+		} else if (res != SMP_RESP_FUNC_ACC) {
+			SAS_DPRINTK("%s: dev %016llx phy 0x%x index 0x%x "
+				    "result 0x%x\n", __FUNCTION__,
+				    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) {
+		SAS_DPRINTK("overflow of indexes: dev %016llx phy 0x%x "
+			    "index 0x%x\n",
+			    SAS_ADDR(dev->sas_addr), phy_id, index);
+	}
+out:
+	kfree(cri_req);
+	kfree(cri_resp);
+	return res;
+}
+
+static inline 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
+ */
+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) {
+		SAS_DPRINTK("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;
+}
+
+#define SMP_BIN_ATTR_NAME "smp_portal"
+
+static void sas_ex_smp_hook(struct domain_device *dev)
+{
+	struct expander_device *ex_dev = &dev->ex_dev;
+	struct bin_attribute *bin_attr = &ex_dev->smp_bin_attr;
+
+	memset(bin_attr, 0, sizeof(*bin_attr));
+
+	bin_attr->attr.name = SMP_BIN_ATTR_NAME;
+	bin_attr->attr.owner = THIS_MODULE;
+	bin_attr->attr.mode = 0600;
+
+	bin_attr->size = 0;
+	bin_attr->private = NULL;
+	bin_attr->read = smp_portal_read;
+	bin_attr->write= smp_portal_write;
+	bin_attr->mmap = NULL;
+
+	ex_dev->smp_portal_pid = -1;	
+	init_MUTEX(&ex_dev->smp_sema);
+}
+
+/**
+ * sas_discover_expander -- expander discovery
+ * @ex: 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) {
+		SAS_DPRINTK("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;
+	sas_ex_smp_hook(dev);
+	sas_kobj_set(dev);
+	return 0;
+out_err:
+	sas_notify_lldd_dev_gone(dev);
+	return res;
+}
+
+static int sas_ex_level_discovery(struct 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 == EDGE_DEV ||
+		    dev->dev_type == FANOUT_DEV) {
+			struct expander_device *ex = &dev->ex_dev;
+			
+			if (level == ex->level)
+				res = sas_ex_discover_devices(dev, -1);
+		}
+	}
+
+	return res;
+}
+
+static int sas_ex_bfs_disc(struct 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;
+
+	dev->ex_dev.level = dev->port->disc.max_level; /* 0 */
+	res = sas_discover_expander(dev);
+	if (!res)
+		sas_ex_bfs_disc(dev->port);
+
+	return res;
+}
+
+void sas_init_ex_attr(void)
+{
+	int i;
+	
+	for (i = 0; i < ARRAY_SIZE(ex_attrs)-1; i++)
+		ex_dev_attrs[i] = &ex_attrs[i].attr;
+	ex_dev_attrs[i] = NULL;
+}
+
+/* ---------- 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_sas_addr(struct domain_device *dev,
+					 int phy_id, u8 *attached_sas_addr)
+{
+	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)
+		memcpy(attached_sas_addr,disc_resp->disc.attached_sas_addr,8);
+
+	kfree(disc_resp);
+	return res;
+}
+
+static int sas_find_bcast_phy(struct domain_device *dev, int *phy_id,
+			      int from_phy)
+{
+	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;
+
+		res = sas_get_phy_change_count(dev, i, &phy_change_count);
+		if (res)
+			goto out;
+		else if (phy_change_count != ex->ex_phy[i].phy_change_count) {
+			ex->ex_phy[i].phy_change_count = phy_change_count;
+			*phy_id = i;
+			return 0;
+		}
+	}
+out:
+	return res;
+}
+
+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;
+}
+
+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 res;
+
+	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) {
+		*src_dev = dev;
+		ex->ex_change_count = ex_change_count;
+	} else {
+		struct domain_device *ch;
+
+		list_for_each_entry(ch, &ex->children, siblings) {
+			if (ch->dev_type == EDGE_DEV ||
+			    ch->dev_type == FANOUT_DEV) {
+				res = sas_find_bcast_dev(ch, src_dev);
+				if (src_dev)
+					return res;
+			}
+		}
+	}
+out:
+	return res;
+}
+
+static void sas_unregister_ex_tree(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) {
+		if (child->dev_type == EDGE_DEV ||
+		    child->dev_type == FANOUT_DEV)
+			sas_unregister_ex_tree(child);
+		else
+			sas_unregister_dev(child);
+	}
+	sas_unregister_dev(dev);
+}
+
+static void sas_unregister_devs_sas_addr(struct domain_device *parent,
+					 int phy_id)
+{
+	struct expander_device *ex_dev = &parent->ex_dev;
+	struct ex_phy *phy = &ex_dev->ex_phy[phy_id];
+	struct domain_device *child, *n;
+
+	list_for_each_entry_safe(child, n, &ex_dev->children, siblings) {
+		if (SAS_ADDR(child->sas_addr) ==
+		    SAS_ADDR(phy->attached_sas_addr)) {
+			if (child->dev_type == EDGE_DEV ||
+			    child->dev_type == FANOUT_DEV)
+				sas_unregister_ex_tree(child);
+			else
+				sas_unregister_dev(child);
+			break;
+		}
+	}
+	sas_disable_routing(parent, phy->attached_sas_addr);
+	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
+}
+
+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 == EDGE_DEV ||
+		    child->dev_type == FANOUT_DEV) {
+			struct expander_device *ex = &child->ex_dev;
+
+			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;
+	int level = dev->ex_dev.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 inline 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;
+	
+	SAS_DPRINTK("ex %016llx phy%d new device attached\n",
+		    SAS_ADDR(dev->sas_addr), phy_id);
+	res = sas_ex_phy_discover(dev, phy_id);
+	if (res)
+		goto out;
+	res = sas_ex_discover_devices(dev, phy_id);
+	if (res)
+		goto out;
+	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 == EDGE_DEV ||
+			    child->dev_type == FANOUT_DEV)
+				res = sas_discover_bfs_by_root(child);
+			break;
+		}
+	}
+out:
+	return res;
+}
+
+static int sas_rediscover_dev(struct domain_device *dev, int phy_id)
+{
+	struct expander_device *ex = &dev->ex_dev;
+	struct ex_phy *phy = &ex->ex_phy[phy_id];
+	u8 attached_sas_addr[8];
+	int res;
+
+	res = sas_get_phy_attached_sas_addr(dev, phy_id, attached_sas_addr);
+	switch (res) {
+	case SMP_RESP_NO_PHY:
+		phy->phy_state = PHY_NOT_PRESENT;
+		sas_unregister_devs_sas_addr(dev, phy_id);
+		goto out; break;
+	case SMP_RESP_PHY_VACANT:
+		phy->phy_state = PHY_VACANT;
+		sas_unregister_devs_sas_addr(dev, phy_id);
+		goto out; break;
+	case SMP_RESP_FUNC_ACC:
+		break;
+	}
+
+	if (SAS_ADDR(attached_sas_addr) == 0) {
+		phy->phy_state = PHY_EMPTY;
+		sas_unregister_devs_sas_addr(dev, phy_id);
+	} else if (SAS_ADDR(attached_sas_addr) ==
+		   SAS_ADDR(phy->attached_sas_addr)) {
+		SAS_DPRINTK("ex %016llx phy 0x%x broadcast flutter\n",
+			    SAS_ADDR(dev->sas_addr), phy_id);
+	} else
+		res = sas_discover_new(dev, phy_id);
+out:
+	return res;
+}
+
+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;
+
+	SAS_DPRINTK("ex %016llx phy%d 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)) {
+				SAS_DPRINTK("phy%d part of wide port with "
+					    "phy%d\n", phy_id, i);
+				goto out;
+			}
+		}
+		res = sas_rediscover_dev(dev, phy_id);
+	} else
+		res = sas_discover_new(dev, phy_id);
+out:
+	return res;
+}
+
+/**
+ * sas_revalidate_domain -- revalidate the domain
+ * @port: port to the domain of interest
+ *
+ * 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)
+		goto out;
+	if (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);
+			if (phy_id == -1)
+				break;
+			res = sas_rediscover(dev, phy_id);
+			i = phy_id + 1;
+		} while (i < ex->num_phys);
+	}
+out:
+	return res;
+}
+
+/* ---------- SMP portal ---------- */
+
+static ssize_t smp_portal_write(struct kobject *kobj, char *buf, loff_t offs,
+				size_t size)
+{
+	struct domain_device *dev = to_dom_device(kobj);
+	struct expander_device *ex = &dev->ex_dev;
+
+	if (offs != 0)
+		return -EFBIG;
+	else if (size == 0)
+		return 0;
+
+	down_interruptible(&ex->smp_sema);
+	if (ex->smp_req)
+		kfree(ex->smp_req);
+	ex->smp_req = kmalloc(size, GFP_USER);
+	if (!ex->smp_req)
+		return -ENOMEM;
+	memcpy(ex->smp_req, buf, size);
+	ex->smp_req_size = size;
+	ex->smp_portal_pid = current->pid;
+	up(&ex->smp_sema);
+
+	return size;
+}
+
+static ssize_t smp_portal_read(struct kobject *kobj, char *buf, loff_t offs,
+			       size_t size)
+{
+	struct domain_device *dev = to_dom_device(kobj);
+	struct expander_device *ex = &dev->ex_dev;
+	u8 *smp_resp;
+	int res = -EINVAL;
+
+	/* XXX: sysfs gives us an offset of 0x10 or 0x8 while in fact
+	 *  it should be 0.
+	 */
+
+	down_interruptible(&ex->smp_sema);
+	if (!ex->smp_req || ex->smp_portal_pid != current->pid)
+		goto out;
+
+	res = 0;
+	if (size == 0)
+		goto out;
+
+	res = -ENOMEM;
+	smp_resp = alloc_smp_resp(size);
+	if (!smp_resp)
+		goto out;
+	res = smp_execute_task(dev, ex->smp_req, ex->smp_req_size,
+			       smp_resp, size);
+	if (!res) {
+		memcpy(buf, smp_resp, size);
+		res = size;
+	}
+
+	kfree(smp_resp);
+out:
+	kfree(ex->smp_req);
+	ex->smp_req = NULL;
+	ex->smp_req_size = 0;
+	ex->smp_portal_pid = -1;
+	up(&ex->smp_sema);
+	return res;
+}