Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

13 files changed, 6659 insertions, 0 deletions

diff --git a/drivers/scsi/libsas/Kconfig b/drivers/scsi/libsas/Kconfig
new file mode 100644
index 000000000..052ee3a26
--- /dev/null
+++ b/drivers/scsi/libsas/Kconfig
@@ -0,0 +1,34 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Kernel configuration file for the SAS Class
+#
+# Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+# Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+#
+
+config SCSI_SAS_LIBSAS
+	tristate "SAS Domain Transport Attributes"
+	depends on SCSI
+	select SCSI_SAS_ATTRS
+	select BLK_DEV_BSGLIB
+	help
+	  This provides transport specific helpers for SAS drivers which
+	  use the domain device construct (like the aic94xxx).
+
+config SCSI_SAS_ATA
+	bool "ATA support for libsas (requires libata)"
+	depends on SCSI_SAS_LIBSAS
+	depends on ATA = y || ATA = SCSI_SAS_LIBSAS
+	select SATA_HOST
+	help
+		Builds in ATA support into libsas.  Will necessitate
+		the loading of libata along with libsas.
+
+config SCSI_SAS_HOST_SMP
+	bool "Support for SMP interpretation for SAS hosts"
+	default y
+	depends on SCSI_SAS_LIBSAS
+	help
+		Allows sas hosts to receive SMP frames.  Selecting this
+		option builds an SMP interpreter into libsas.  Say
+		N here if you want to save the few kb this consumes.
diff --git a/drivers/scsi/libsas/Makefile b/drivers/scsi/libsas/Makefile
new file mode 100644
index 000000000..e63a54f5a
--- /dev/null
+++ b/drivers/scsi/libsas/Makefile
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Kernel Makefile for the libsas helpers
+#
+# Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+# Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+#
+
+obj-$(CONFIG_SCSI_SAS_LIBSAS) += libsas.o
+libsas-y +=  sas_init.o     \
+		sas_phy.o      \
+		sas_port.o     \
+		sas_event.o    \
+		sas_discover.o \
+		sas_expander.o \
+		sas_scsi_host.o \
+		sas_task.o
+libsas-$(CONFIG_SCSI_SAS_ATA) +=	sas_ata.o
+libsas-$(CONFIG_SCSI_SAS_HOST_SMP) +=	sas_host_smp.o
+
+ccflags-y := -DDEBUG
diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
new file mode 100644
index 000000000..f92b88936
--- /dev/null
+++ b/drivers/scsi/libsas/sas_ata.c
@@ -0,0 +1,864 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Support for SATA devices on Serial Attached SCSI (SAS) controllers
+ *
+ * Copyright (C) 2006 IBM Corporation
+ *
+ * Written by: Darrick J. Wong <djwong@us.ibm.com>, IBM Corporation
+ */
+
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/async.h>
+#include <linux/export.h>
+
+#include <scsi/sas_ata.h>
+#include "sas_internal.h"
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_sas.h>
+#include "../scsi_sas_internal.h"
+#include "../scsi_transport_api.h"
+#include <scsi/scsi_eh.h>
+
+static enum ata_completion_errors sas_to_ata_err(struct task_status_struct *ts)
+{
+	/* Cheesy attempt to translate SAS errors into ATA.  Hah! */
+
+	/* transport error */
+	if (ts->resp == SAS_TASK_UNDELIVERED)
+		return AC_ERR_ATA_BUS;
+
+	/* ts->resp == SAS_TASK_COMPLETE */
+	/* task delivered, what happened afterwards? */
+	switch (ts->stat) {
+		case SAS_DEV_NO_RESPONSE:
+			return AC_ERR_TIMEOUT;
+
+		case SAS_INTERRUPTED:
+		case SAS_PHY_DOWN:
+		case SAS_NAK_R_ERR:
+			return AC_ERR_ATA_BUS;
+
+
+		case SAS_DATA_UNDERRUN:
+			/*
+			 * Some programs that use the taskfile interface
+			 * (smartctl in particular) can cause underrun
+			 * problems.  Ignore these errors, perhaps at our
+			 * peril.
+			 */
+			return 0;
+
+		case SAS_DATA_OVERRUN:
+		case SAS_QUEUE_FULL:
+		case SAS_DEVICE_UNKNOWN:
+		case SAS_SG_ERR:
+			return AC_ERR_INVALID;
+
+		case SAS_OPEN_TO:
+		case SAS_OPEN_REJECT:
+			pr_warn("%s: Saw error %d.  What to do?\n",
+				__func__, ts->stat);
+			return AC_ERR_OTHER;
+
+		case SAM_STAT_CHECK_CONDITION:
+		case SAS_ABORTED_TASK:
+			return AC_ERR_DEV;
+
+		case SAS_PROTO_RESPONSE:
+			/* This means the ending_fis has the error
+			 * value; return 0 here to collect it */
+			return 0;
+		default:
+			return 0;
+	}
+}
+
+static void sas_ata_task_done(struct sas_task *task)
+{
+	struct ata_queued_cmd *qc = task->uldd_task;
+	struct domain_device *dev = task->dev;
+	struct task_status_struct *stat = &task->task_status;
+	struct ata_task_resp *resp = (struct ata_task_resp *)stat->buf;
+	struct sas_ha_struct *sas_ha = dev->port->ha;
+	enum ata_completion_errors ac;
+	unsigned long flags;
+	struct ata_link *link;
+	struct ata_port *ap;
+
+	spin_lock_irqsave(&dev->done_lock, flags);
+	if (test_bit(SAS_HA_FROZEN, &sas_ha->state))
+		task = NULL;
+	else if (qc && qc->scsicmd)
+		ASSIGN_SAS_TASK(qc->scsicmd, NULL);
+	spin_unlock_irqrestore(&dev->done_lock, flags);
+
+	/* check if libsas-eh got to the task before us */
+	if (unlikely(!task))
+		return;
+
+	if (!qc)
+		goto qc_already_gone;
+
+	ap = qc->ap;
+	link = &ap->link;
+
+	spin_lock_irqsave(ap->lock, flags);
+	/* check if we lost the race with libata/sas_ata_post_internal() */
+	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN)) {
+		spin_unlock_irqrestore(ap->lock, flags);
+		if (qc->scsicmd)
+			goto qc_already_gone;
+		else {
+			/* if eh is not involved and the port is frozen then the
+			 * ata internal abort process has taken responsibility
+			 * for this sas_task
+			 */
+			return;
+		}
+	}
+
+	if (stat->stat == SAS_PROTO_RESPONSE ||
+	    stat->stat == SAS_SAM_STAT_GOOD ||
+	    (stat->stat == SAS_SAM_STAT_CHECK_CONDITION &&
+	      dev->sata_dev.class == ATA_DEV_ATAPI)) {
+		memcpy(dev->sata_dev.fis, resp->ending_fis, ATA_RESP_FIS_SIZE);
+
+		if (!link->sactive) {
+			qc->err_mask |= ac_err_mask(dev->sata_dev.fis[2]);
+		} else {
+			link->eh_info.err_mask |= ac_err_mask(dev->sata_dev.fis[2]);
+			if (unlikely(link->eh_info.err_mask))
+				qc->flags |= ATA_QCFLAG_FAILED;
+		}
+	} else {
+		ac = sas_to_ata_err(stat);
+		if (ac) {
+			pr_warn("%s: SAS error 0x%x\n", __func__, stat->stat);
+			/* We saw a SAS error. Send a vague error. */
+			if (!link->sactive) {
+				qc->err_mask = ac;
+			} else {
+				link->eh_info.err_mask |= AC_ERR_DEV;
+				qc->flags |= ATA_QCFLAG_FAILED;
+			}
+
+			dev->sata_dev.fis[3] = 0x04; /* status err */
+			dev->sata_dev.fis[2] = ATA_ERR;
+		}
+	}
+
+	qc->lldd_task = NULL;
+	ata_qc_complete(qc);
+	spin_unlock_irqrestore(ap->lock, flags);
+
+qc_already_gone:
+	sas_free_task(task);
+}
+
+static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
+	__must_hold(ap->lock)
+{
+	struct sas_task *task;
+	struct scatterlist *sg;
+	int ret = AC_ERR_SYSTEM;
+	unsigned int si, xfer = 0;
+	struct ata_port *ap = qc->ap;
+	struct domain_device *dev = ap->private_data;
+	struct sas_ha_struct *sas_ha = dev->port->ha;
+	struct Scsi_Host *host = sas_ha->core.shost;
+	struct sas_internal *i = to_sas_internal(host->transportt);
+
+	/* TODO: we should try to remove that unlock */
+	spin_unlock(ap->lock);
+
+	/* If the device fell off, no sense in issuing commands */
+	if (test_bit(SAS_DEV_GONE, &dev->state))
+		goto out;
+
+	task = sas_alloc_task(GFP_ATOMIC);
+	if (!task)
+		goto out;
+	task->dev = dev;
+	task->task_proto = SAS_PROTOCOL_STP;
+	task->task_done = sas_ata_task_done;
+
+	if (qc->tf.command == ATA_CMD_FPDMA_WRITE ||
+	    qc->tf.command == ATA_CMD_FPDMA_READ ||
+	    qc->tf.command == ATA_CMD_FPDMA_RECV ||
+	    qc->tf.command == ATA_CMD_FPDMA_SEND ||
+	    qc->tf.command == ATA_CMD_NCQ_NON_DATA) {
+		/* Need to zero out the tag libata assigned us */
+		qc->tf.nsect = 0;
+	}
+
+	ata_tf_to_fis(&qc->tf, qc->dev->link->pmp, 1, (u8 *)&task->ata_task.fis);
+	task->uldd_task = qc;
+	if (ata_is_atapi(qc->tf.protocol)) {
+		memcpy(task->ata_task.atapi_packet, qc->cdb, qc->dev->cdb_len);
+		task->total_xfer_len = qc->nbytes;
+		task->num_scatter = qc->n_elem;
+		task->data_dir = qc->dma_dir;
+	} else if (!ata_is_data(qc->tf.protocol)) {
+		task->data_dir = DMA_NONE;
+	} else {
+		for_each_sg(qc->sg, sg, qc->n_elem, si)
+			xfer += sg_dma_len(sg);
+
+		task->total_xfer_len = xfer;
+		task->num_scatter = si;
+		task->data_dir = qc->dma_dir;
+	}
+	task->scatter = qc->sg;
+	task->ata_task.retry_count = 1;
+	task->task_state_flags = SAS_TASK_STATE_PENDING;
+	qc->lldd_task = task;
+
+	task->ata_task.use_ncq = ata_is_ncq(qc->tf.protocol);
+	task->ata_task.dma_xfer = ata_is_dma(qc->tf.protocol);
+
+	if (qc->scsicmd)
+		ASSIGN_SAS_TASK(qc->scsicmd, task);
+
+	ret = i->dft->lldd_execute_task(task, GFP_ATOMIC);
+	if (ret) {
+		pr_debug("lldd_execute_task returned: %d\n", ret);
+
+		if (qc->scsicmd)
+			ASSIGN_SAS_TASK(qc->scsicmd, NULL);
+		sas_free_task(task);
+		qc->lldd_task = NULL;
+		ret = AC_ERR_SYSTEM;
+	}
+
+ out:
+	spin_lock(ap->lock);
+	return ret;
+}
+
+static bool sas_ata_qc_fill_rtf(struct ata_queued_cmd *qc)
+{
+	struct domain_device *dev = qc->ap->private_data;
+
+	ata_tf_from_fis(dev->sata_dev.fis, &qc->result_tf);
+	return true;
+}
+
+static struct sas_internal *dev_to_sas_internal(struct domain_device *dev)
+{
+	return to_sas_internal(dev->port->ha->core.shost->transportt);
+}
+
+static int sas_get_ata_command_set(struct domain_device *dev);
+
+int sas_get_ata_info(struct domain_device *dev, struct ex_phy *phy)
+{
+	if (phy->attached_tproto & SAS_PROTOCOL_STP)
+		dev->tproto = phy->attached_tproto;
+	if (phy->attached_sata_dev)
+		dev->tproto |= SAS_SATA_DEV;
+
+	if (phy->attached_dev_type == SAS_SATA_PENDING)
+		dev->dev_type = SAS_SATA_PENDING;
+	else {
+		int res;
+
+		dev->dev_type = SAS_SATA_DEV;
+		res = sas_get_report_phy_sata(dev->parent, phy->phy_id,
+					      &dev->sata_dev.rps_resp);
+		if (res) {
+			pr_debug("report phy sata to %016llx:%02d returned 0x%x\n",
+				 SAS_ADDR(dev->parent->sas_addr),
+				 phy->phy_id, res);
+			return res;
+		}
+		memcpy(dev->frame_rcvd, &dev->sata_dev.rps_resp.rps.fis,
+		       sizeof(struct dev_to_host_fis));
+		dev->sata_dev.class = sas_get_ata_command_set(dev);
+	}
+	return 0;
+}
+
+static int sas_ata_clear_pending(struct domain_device *dev, struct ex_phy *phy)
+{
+	int res;
+
+	/* we weren't pending, so successfully end the reset sequence now */
+	if (dev->dev_type != SAS_SATA_PENDING)
+		return 1;
+
+	/* hmmm, if this succeeds do we need to repost the domain_device to the
+	 * lldd so it can pick up new parameters?
+	 */
+	res = sas_get_ata_info(dev, phy);
+	if (res)
+		return 0; /* retry */
+	else
+		return 1;
+}
+
+static int smp_ata_check_ready(struct ata_link *link)
+{
+	int res;
+	struct ata_port *ap = link->ap;
+	struct domain_device *dev = ap->private_data;
+	struct domain_device *ex_dev = dev->parent;
+	struct sas_phy *phy = sas_get_local_phy(dev);
+	struct ex_phy *ex_phy = &ex_dev->ex_dev.ex_phy[phy->number];
+
+	res = sas_ex_phy_discover(ex_dev, phy->number);
+	sas_put_local_phy(phy);
+
+	/* break the wait early if the expander is unreachable,
+	 * otherwise keep polling
+	 */
+	if (res == -ECOMM)
+		return res;
+	if (res != SMP_RESP_FUNC_ACC)
+		return 0;
+
+	switch (ex_phy->attached_dev_type) {
+	case SAS_SATA_PENDING:
+		return 0;
+	case SAS_END_DEVICE:
+		if (ex_phy->attached_sata_dev)
+			return sas_ata_clear_pending(dev, ex_phy);
+		fallthrough;
+	default:
+		return -ENODEV;
+	}
+}
+
+static int local_ata_check_ready(struct ata_link *link)
+{
+	struct ata_port *ap = link->ap;
+	struct domain_device *dev = ap->private_data;
+	struct sas_internal *i = dev_to_sas_internal(dev);
+
+	if (i->dft->lldd_ata_check_ready)
+		return i->dft->lldd_ata_check_ready(dev);
+	else {
+		/* lldd's that don't implement 'ready' checking get the
+		 * old default behavior of not coordinating reset
+		 * recovery with libata
+		 */
+		return 1;
+	}
+}
+
+static int sas_ata_printk(const char *level, const struct domain_device *ddev,
+			  const char *fmt, ...)
+{
+	struct ata_port *ap = ddev->sata_dev.ap;
+	struct device *dev = &ddev->rphy->dev;
+	struct va_format vaf;
+	va_list args;
+	int r;
+
+	va_start(args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	r = printk("%s" SAS_FMT "ata%u: %s: %pV",
+		   level, ap->print_id, dev_name(dev), &vaf);
+
+	va_end(args);
+
+	return r;
+}
+
+static int sas_ata_hard_reset(struct ata_link *link, unsigned int *class,
+			      unsigned long deadline)
+{
+	int ret = 0, res;
+	struct sas_phy *phy;
+	struct ata_port *ap = link->ap;
+	int (*check_ready)(struct ata_link *link);
+	struct domain_device *dev = ap->private_data;
+	struct sas_internal *i = dev_to_sas_internal(dev);
+
+	res = i->dft->lldd_I_T_nexus_reset(dev);
+	if (res == -ENODEV)
+		return res;
+
+	if (res != TMF_RESP_FUNC_COMPLETE)
+		sas_ata_printk(KERN_DEBUG, dev, "Unable to reset ata device?\n");
+
+	phy = sas_get_local_phy(dev);
+	if (scsi_is_sas_phy_local(phy))
+		check_ready = local_ata_check_ready;
+	else
+		check_ready = smp_ata_check_ready;
+	sas_put_local_phy(phy);
+
+	ret = ata_wait_after_reset(link, deadline, check_ready);
+	if (ret && ret != -EAGAIN)
+		sas_ata_printk(KERN_ERR, dev, "reset failed (errno=%d)\n", ret);
+
+	*class = dev->sata_dev.class;
+
+	ap->cbl = ATA_CBL_SATA;
+	return ret;
+}
+
+/*
+ * notify the lldd to forget the sas_task for this internal ata command
+ * that bypasses scsi-eh
+ */
+static void sas_ata_internal_abort(struct sas_task *task)
+{
+	struct sas_internal *si = dev_to_sas_internal(task->dev);
+	unsigned long flags;
+	int res;
+
+	spin_lock_irqsave(&task->task_state_lock, flags);
+	if (task->task_state_flags & SAS_TASK_STATE_ABORTED ||
+	    task->task_state_flags & SAS_TASK_STATE_DONE) {
+		spin_unlock_irqrestore(&task->task_state_lock, flags);
+		pr_debug("%s: Task %p already finished.\n", __func__, task);
+		goto out;
+	}
+	task->task_state_flags |= SAS_TASK_STATE_ABORTED;
+	spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+	res = si->dft->lldd_abort_task(task);
+
+	spin_lock_irqsave(&task->task_state_lock, flags);
+	if (task->task_state_flags & SAS_TASK_STATE_DONE ||
+	    res == TMF_RESP_FUNC_COMPLETE) {
+		spin_unlock_irqrestore(&task->task_state_lock, flags);
+		goto out;
+	}
+
+	/* XXX we are not prepared to deal with ->lldd_abort_task()
+	 * failures.  TODO: lldds need to unconditionally forget about
+	 * aborted ata tasks, otherwise we (likely) leak the sas task
+	 * here
+	 */
+	pr_warn("%s: Task %p leaked.\n", __func__, task);
+
+	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);
+
+	return;
+ out:
+	sas_free_task(task);
+}
+
+static void sas_ata_post_internal(struct ata_queued_cmd *qc)
+{
+	if (qc->flags & ATA_QCFLAG_FAILED)
+		qc->err_mask |= AC_ERR_OTHER;
+
+	if (qc->err_mask) {
+		/*
+		 * Find the sas_task and kill it.  By this point, libata
+		 * has decided to kill the qc and has frozen the port.
+		 * In this state sas_ata_task_done() will no longer free
+		 * the sas_task, so we need to notify the lldd (via
+		 * ->lldd_abort_task) that the task is dead and free it
+		 *  ourselves.
+		 */
+		struct sas_task *task = qc->lldd_task;
+
+		qc->lldd_task = NULL;
+		if (!task)
+			return;
+		task->uldd_task = NULL;
+		sas_ata_internal_abort(task);
+	}
+}
+
+
+static void sas_ata_set_dmamode(struct ata_port *ap, struct ata_device *ata_dev)
+{
+	struct domain_device *dev = ap->private_data;
+	struct sas_internal *i = dev_to_sas_internal(dev);
+
+	if (i->dft->lldd_ata_set_dmamode)
+		i->dft->lldd_ata_set_dmamode(dev);
+}
+
+static void sas_ata_sched_eh(struct ata_port *ap)
+{
+	struct domain_device *dev = ap->private_data;
+	struct sas_ha_struct *ha = dev->port->ha;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ha->lock, flags);
+	if (!test_and_set_bit(SAS_DEV_EH_PENDING, &dev->state))
+		ha->eh_active++;
+	ata_std_sched_eh(ap);
+	spin_unlock_irqrestore(&ha->lock, flags);
+}
+
+void sas_ata_end_eh(struct ata_port *ap)
+{
+	struct domain_device *dev = ap->private_data;
+	struct sas_ha_struct *ha = dev->port->ha;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ha->lock, flags);
+	if (test_and_clear_bit(SAS_DEV_EH_PENDING, &dev->state))
+		ha->eh_active--;
+	spin_unlock_irqrestore(&ha->lock, flags);
+}
+
+static int sas_ata_prereset(struct ata_link *link, unsigned long deadline)
+{
+	struct ata_port *ap = link->ap;
+	struct domain_device *dev = ap->private_data;
+	struct sas_phy *local_phy = sas_get_local_phy(dev);
+	int res = 0;
+
+	if (!local_phy->enabled || test_bit(SAS_DEV_GONE, &dev->state))
+		res = -ENOENT;
+	sas_put_local_phy(local_phy);
+
+	return res;
+}
+
+static struct ata_port_operations sas_sata_ops = {
+	.prereset		= sas_ata_prereset,
+	.hardreset		= sas_ata_hard_reset,
+	.error_handler		= ata_std_error_handler,
+	.post_internal_cmd	= sas_ata_post_internal,
+	.qc_defer               = ata_std_qc_defer,
+	.qc_prep		= ata_noop_qc_prep,
+	.qc_issue		= sas_ata_qc_issue,
+	.qc_fill_rtf		= sas_ata_qc_fill_rtf,
+	.port_start		= ata_sas_port_start,
+	.port_stop		= ata_sas_port_stop,
+	.set_dmamode		= sas_ata_set_dmamode,
+	.sched_eh		= sas_ata_sched_eh,
+	.end_eh			= sas_ata_end_eh,
+};
+
+static struct ata_port_info sata_port_info = {
+	.flags = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ |
+		 ATA_FLAG_SAS_HOST | ATA_FLAG_FPDMA_AUX,
+	.pio_mask = ATA_PIO4,
+	.mwdma_mask = ATA_MWDMA2,
+	.udma_mask = ATA_UDMA6,
+	.port_ops = &sas_sata_ops
+};
+
+int sas_ata_init(struct domain_device *found_dev)
+{
+	struct sas_ha_struct *ha = found_dev->port->ha;
+	struct Scsi_Host *shost = ha->core.shost;
+	struct ata_host *ata_host;
+	struct ata_port *ap;
+	int rc;
+
+	ata_host = kzalloc(sizeof(*ata_host), GFP_KERNEL);
+	if (!ata_host)	{
+		pr_err("ata host alloc failed.\n");
+		return -ENOMEM;
+	}
+
+	ata_host_init(ata_host, ha->dev, &sas_sata_ops);
+
+	ap = ata_sas_port_alloc(ata_host, &sata_port_info, shost);
+	if (!ap) {
+		pr_err("ata_sas_port_alloc failed.\n");
+		rc = -ENODEV;
+		goto free_host;
+	}
+
+	ap->private_data = found_dev;
+	ap->cbl = ATA_CBL_SATA;
+	ap->scsi_host = shost;
+	rc = ata_sas_port_init(ap);
+	if (rc)
+		goto destroy_port;
+
+	rc = ata_sas_tport_add(ata_host->dev, ap);
+	if (rc)
+		goto destroy_port;
+
+	found_dev->sata_dev.ata_host = ata_host;
+	found_dev->sata_dev.ap = ap;
+
+	return 0;
+
+destroy_port:
+	ata_sas_port_destroy(ap);
+free_host:
+	ata_host_put(ata_host);
+	return rc;
+}
+
+void sas_ata_task_abort(struct sas_task *task)
+{
+	struct ata_queued_cmd *qc = task->uldd_task;
+	struct completion *waiting;
+
+	/* Bounce SCSI-initiated commands to the SCSI EH */
+	if (qc->scsicmd) {
+		blk_abort_request(qc->scsicmd->request);
+		return;
+	}
+
+	/* Internal command, fake a timeout and complete. */
+	qc->flags &= ~ATA_QCFLAG_ACTIVE;
+	qc->flags |= ATA_QCFLAG_FAILED;
+	qc->err_mask |= AC_ERR_TIMEOUT;
+	waiting = qc->private_data;
+	complete(waiting);
+}
+
+static int sas_get_ata_command_set(struct domain_device *dev)
+{
+	struct dev_to_host_fis *fis =
+		(struct dev_to_host_fis *) dev->frame_rcvd;
+	struct ata_taskfile tf;
+
+	if (dev->dev_type == SAS_SATA_PENDING)
+		return ATA_DEV_UNKNOWN;
+
+	ata_tf_from_fis((const u8 *)fis, &tf);
+
+	return ata_dev_classify(&tf);
+}
+
+void sas_probe_sata(struct asd_sas_port *port)
+{
+	struct domain_device *dev, *n;
+
+	mutex_lock(&port->ha->disco_mutex);
+	list_for_each_entry(dev, &port->disco_list, disco_list_node) {
+		if (!dev_is_sata(dev))
+			continue;
+
+		ata_sas_async_probe(dev->sata_dev.ap);
+	}
+	mutex_unlock(&port->ha->disco_mutex);
+
+	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
+		if (!dev_is_sata(dev))
+			continue;
+
+		sas_ata_wait_eh(dev);
+
+		/* if libata could not bring the link up, don't surface
+		 * the device
+		 */
+		if (!ata_dev_enabled(sas_to_ata_dev(dev)))
+			sas_fail_probe(dev, __func__, -ENODEV);
+	}
+
+}
+
+static void sas_ata_flush_pm_eh(struct asd_sas_port *port, const char *func)
+{
+	struct domain_device *dev, *n;
+
+	list_for_each_entry_safe(dev, n, &port->dev_list, dev_list_node) {
+		if (!dev_is_sata(dev))
+			continue;
+
+		sas_ata_wait_eh(dev);
+
+		/* if libata failed to power manage the device, tear it down */
+		if (ata_dev_disabled(sas_to_ata_dev(dev)))
+			sas_fail_probe(dev, func, -ENODEV);
+	}
+}
+
+void sas_suspend_sata(struct asd_sas_port *port)
+{
+	struct domain_device *dev;
+
+	mutex_lock(&port->ha->disco_mutex);
+	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
+		struct sata_device *sata;
+
+		if (!dev_is_sata(dev))
+			continue;
+
+		sata = &dev->sata_dev;
+		if (sata->ap->pm_mesg.event == PM_EVENT_SUSPEND)
+			continue;
+
+		ata_sas_port_suspend(sata->ap);
+	}
+	mutex_unlock(&port->ha->disco_mutex);
+
+	sas_ata_flush_pm_eh(port, __func__);
+}
+
+void sas_resume_sata(struct asd_sas_port *port)
+{
+	struct domain_device *dev;
+
+	mutex_lock(&port->ha->disco_mutex);
+	list_for_each_entry(dev, &port->dev_list, dev_list_node) {
+		struct sata_device *sata;
+
+		if (!dev_is_sata(dev))
+			continue;
+
+		sata = &dev->sata_dev;
+		if (sata->ap->pm_mesg.event == PM_EVENT_ON)
+			continue;
+
+		ata_sas_port_resume(sata->ap);
+	}
+	mutex_unlock(&port->ha->disco_mutex);
+
+	sas_ata_flush_pm_eh(port, __func__);
+}
+
+/**
+ * sas_discover_sata - discover an STP/SATA domain device
+ * @dev: pointer to struct domain_device of interest
+ *
+ * Devices directly attached to a HA port, have no parents.  All other
+ * devices do, and should have their "parent" pointer set appropriately
+ * before calling this function.
+ */
+int sas_discover_sata(struct domain_device *dev)
+{
+	if (dev->dev_type == SAS_SATA_PM)
+		return -ENODEV;
+
+	dev->sata_dev.class = sas_get_ata_command_set(dev);
+	sas_fill_in_rphy(dev, dev->rphy);
+
+	return sas_notify_lldd_dev_found(dev);
+}
+
+static void async_sas_ata_eh(void *data, async_cookie_t cookie)
+{
+	struct domain_device *dev = data;
+	struct ata_port *ap = dev->sata_dev.ap;
+	struct sas_ha_struct *ha = dev->port->ha;
+
+	sas_ata_printk(KERN_DEBUG, dev, "dev error handler\n");
+	ata_scsi_port_error_handler(ha->core.shost, ap);
+	sas_put_device(dev);
+}
+
+void sas_ata_strategy_handler(struct Scsi_Host *shost)
+{
+	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+	ASYNC_DOMAIN_EXCLUSIVE(async);
+	int i;
+
+	/* it's ok to defer revalidation events during ata eh, these
+	 * disks are in one of three states:
+	 * 1/ present for initial domain discovery, and these
+	 *    resets will cause bcn flutters
+	 * 2/ hot removed, we'll discover that after eh fails
+	 * 3/ hot added after initial discovery, lost the race, and need
+	 *    to catch the next train.
+	 */
+	sas_disable_revalidation(sas_ha);
+
+	spin_lock_irq(&sas_ha->phy_port_lock);
+	for (i = 0; i < sas_ha->num_phys; i++) {
+		struct asd_sas_port *port = sas_ha->sas_port[i];
+		struct domain_device *dev;
+
+		spin_lock(&port->dev_list_lock);
+		list_for_each_entry(dev, &port->dev_list, dev_list_node) {
+			if (!dev_is_sata(dev))
+				continue;
+
+			/* hold a reference over eh since we may be
+			 * racing with final remove once all commands
+			 * are completed
+			 */
+			kref_get(&dev->kref);
+
+			async_schedule_domain(async_sas_ata_eh, dev, &async);
+		}
+		spin_unlock(&port->dev_list_lock);
+	}
+	spin_unlock_irq(&sas_ha->phy_port_lock);
+
+	async_synchronize_full_domain(&async);
+
+	sas_enable_revalidation(sas_ha);
+}
+
+void sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q,
+		struct list_head *done_q)
+{
+	struct scsi_cmnd *cmd, *n;
+	struct domain_device *eh_dev;
+
+	do {
+		LIST_HEAD(sata_q);
+		eh_dev = NULL;
+
+		list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
+			struct domain_device *ddev = cmd_to_domain_dev(cmd);
+
+			if (!dev_is_sata(ddev) || TO_SAS_TASK(cmd))
+				continue;
+			if (eh_dev && eh_dev != ddev)
+				continue;
+			eh_dev = ddev;
+			list_move(&cmd->eh_entry, &sata_q);
+		}
+
+		if (!list_empty(&sata_q)) {
+			struct ata_port *ap = eh_dev->sata_dev.ap;
+
+			sas_ata_printk(KERN_DEBUG, eh_dev, "cmd error handler\n");
+			ata_scsi_cmd_error_handler(shost, ap, &sata_q);
+			/*
+			 * ata's error handler may leave the cmd on the list
+			 * so make sure they don't remain on a stack list
+			 * about to go out of scope.
+			 *
+			 * This looks strange, since the commands are
+			 * now part of no list, but the next error
+			 * action will be ata_port_error_handler()
+			 * which takes no list and sweeps them up
+			 * anyway from the ata tag array.
+			 */
+			while (!list_empty(&sata_q))
+				list_del_init(sata_q.next);
+		}
+	} while (eh_dev);
+}
+
+void sas_ata_schedule_reset(struct domain_device *dev)
+{
+	struct ata_eh_info *ehi;
+	struct ata_port *ap;
+	unsigned long flags;
+
+	if (!dev_is_sata(dev))
+		return;
+
+	ap = dev->sata_dev.ap;
+	ehi = &ap->link.eh_info;
+
+	spin_lock_irqsave(ap->lock, flags);
+	ehi->err_mask |= AC_ERR_TIMEOUT;
+	ehi->action |= ATA_EH_RESET;
+	ata_port_schedule_eh(ap);
+	spin_unlock_irqrestore(ap->lock, flags);
+}
+EXPORT_SYMBOL_GPL(sas_ata_schedule_reset);
+
+void sas_ata_wait_eh(struct domain_device *dev)
+{
+	struct ata_port *ap;
+
+	if (!dev_is_sata(dev))
+		return;
+
+	ap = dev->sata_dev.ap;
+	ata_port_wait_eh(ap);
+}
diff --git a/drivers/scsi/libsas/sas_discover.c b/drivers/scsi/libsas/sas_discover.c
new file mode 100644
index 000000000..161c9b387
--- /dev/null
+++ b/drivers/scsi/libsas/sas_discover.c
@@ -0,0 +1,587 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Serial Attached SCSI (SAS) Discover process
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+ */
+
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/async.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_eh.h>
+#include "sas_internal.h"
+
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_sas.h>
+#include <scsi/sas_ata.h>
+#include "../scsi_sas_internal.h"
+
+/* ---------- Basic task processing for discovery purposes ---------- */
+
+void sas_init_dev(struct domain_device *dev)
+{
+	switch (dev->dev_type) {
+	case SAS_END_DEVICE:
+		INIT_LIST_HEAD(&dev->ssp_dev.eh_list_node);
+		break;
+	case SAS_EDGE_EXPANDER_DEVICE:
+	case SAS_FANOUT_EXPANDER_DEVICE:
+		INIT_LIST_HEAD(&dev->ex_dev.children);
+		mutex_init(&dev->ex_dev.cmd_mutex);
+		break;
+	default:
+		break;
+	}
+}
+
+/* ---------- Domain device discovery ---------- */
+
+/**
+ * sas_get_port_device - Discover devices which caused port creation
+ * @port: pointer to struct sas_port of interest
+ *
+ * Devices directly attached to a HA port, have no parent.  This is
+ * how we know they are (domain) "root" devices.  All other devices
+ * do, and should have their "parent" pointer set appropriately as
+ * soon as a child device is discovered.
+ */
+static int sas_get_port_device(struct asd_sas_port *port)
+{
+	struct asd_sas_phy *phy;
+	struct sas_rphy *rphy;
+	struct domain_device *dev;
+	int rc = -ENODEV;
+
+	dev = sas_alloc_device();
+	if (!dev)
+		return -ENOMEM;
+
+	spin_lock_irq(&port->phy_list_lock);
+	if (list_empty(&port->phy_list)) {
+		spin_unlock_irq(&port->phy_list_lock);
+		sas_put_device(dev);
+		return -ENODEV;
+	}
+	phy = container_of(port->phy_list.next, struct asd_sas_phy, port_phy_el);
+	spin_lock(&phy->frame_rcvd_lock);
+	memcpy(dev->frame_rcvd, phy->frame_rcvd, min(sizeof(dev->frame_rcvd),
+					     (size_t)phy->frame_rcvd_size));
+	spin_unlock(&phy->frame_rcvd_lock);
+	spin_unlock_irq(&port->phy_list_lock);
+
+	if (dev->frame_rcvd[0] == 0x34 && port->oob_mode == SATA_OOB_MODE) {
+		struct dev_to_host_fis *fis =
+			(struct dev_to_host_fis *) dev->frame_rcvd;
+		if (fis->interrupt_reason == 1 && fis->lbal == 1 &&
+		    fis->byte_count_low==0x69 && fis->byte_count_high == 0x96
+		    && (fis->device & ~0x10) == 0)
+			dev->dev_type = SAS_SATA_PM;
+		else
+			dev->dev_type = SAS_SATA_DEV;
+		dev->tproto = SAS_PROTOCOL_SATA;
+	} else if (port->oob_mode == SAS_OOB_MODE) {
+		struct sas_identify_frame *id =
+			(struct sas_identify_frame *) dev->frame_rcvd;
+		dev->dev_type = id->dev_type;
+		dev->iproto = id->initiator_bits;
+		dev->tproto = id->target_bits;
+	} else {
+		/* If the oob mode is OOB_NOT_CONNECTED, the port is
+		 * disconnected due to race with PHY down. We cannot
+		 * continue to discover this port
+		 */
+		sas_put_device(dev);
+		pr_warn("Port %016llx is disconnected when discovering\n",
+			SAS_ADDR(port->attached_sas_addr));
+		return -ENODEV;
+	}
+
+	sas_init_dev(dev);
+
+	dev->port = port;
+	switch (dev->dev_type) {
+	case SAS_SATA_DEV:
+		rc = sas_ata_init(dev);
+		if (rc) {
+			rphy = NULL;
+			break;
+		}
+		fallthrough;
+	case SAS_END_DEVICE:
+		rphy = sas_end_device_alloc(port->port);
+		break;
+	case SAS_EDGE_EXPANDER_DEVICE:
+		rphy = sas_expander_alloc(port->port,
+					  SAS_EDGE_EXPANDER_DEVICE);
+		break;
+	case SAS_FANOUT_EXPANDER_DEVICE:
+		rphy = sas_expander_alloc(port->port,
+					  SAS_FANOUT_EXPANDER_DEVICE);
+		break;
+	default:
+		pr_warn("ERROR: Unidentified device type %d\n", dev->dev_type);
+		rphy = NULL;
+		break;
+	}
+
+	if (!rphy) {
+		sas_put_device(dev);
+		return rc;
+	}
+
+	rphy->identify.phy_identifier = phy->phy->identify.phy_identifier;
+	memcpy(dev->sas_addr, port->attached_sas_addr, SAS_ADDR_SIZE);
+	sas_fill_in_rphy(dev, rphy);
+	sas_hash_addr(dev->hashed_sas_addr, dev->sas_addr);
+	port->port_dev = dev;
+	dev->linkrate = port->linkrate;
+	dev->min_linkrate = port->linkrate;
+	dev->max_linkrate = port->linkrate;
+	dev->pathways = port->num_phys;
+	memset(port->disc.fanout_sas_addr, 0, SAS_ADDR_SIZE);
+	memset(port->disc.eeds_a, 0, SAS_ADDR_SIZE);
+	memset(port->disc.eeds_b, 0, SAS_ADDR_SIZE);
+	port->disc.max_level = 0;
+	sas_device_set_phy(dev, port->port);
+
+	dev->rphy = rphy;
+	get_device(&dev->rphy->dev);
+
+	if (dev_is_sata(dev) || dev->dev_type == SAS_END_DEVICE)
+		list_add_tail(&dev->disco_list_node, &port->disco_list);
+	else {
+		spin_lock_irq(&port->dev_list_lock);
+		list_add_tail(&dev->dev_list_node, &port->dev_list);
+		spin_unlock_irq(&port->dev_list_lock);
+	}
+
+	spin_lock_irq(&port->phy_list_lock);
+	list_for_each_entry(phy, &port->phy_list, port_phy_el)
+		sas_phy_set_target(phy, dev);
+	spin_unlock_irq(&port->phy_list_lock);
+
+	return 0;
+}
+
+/* ---------- Discover and Revalidate ---------- */
+
+int sas_notify_lldd_dev_found(struct domain_device *dev)
+{
+	int res = 0;
+	struct sas_ha_struct *sas_ha = dev->port->ha;
+	struct Scsi_Host *shost = sas_ha->core.shost;
+	struct sas_internal *i = to_sas_internal(shost->transportt);
+
+	if (!i->dft->lldd_dev_found)
+		return 0;
+
+	res = i->dft->lldd_dev_found(dev);
+	if (res) {
+		pr_warn("driver on host %s cannot handle device %016llx, error:%d\n",
+			dev_name(sas_ha->dev),
+			SAS_ADDR(dev->sas_addr), res);
+		return res;
+	}
+	set_bit(SAS_DEV_FOUND, &dev->state);
+	kref_get(&dev->kref);
+	return 0;
+}
+
+
+void sas_notify_lldd_dev_gone(struct domain_device *dev)
+{
+	struct sas_ha_struct *sas_ha = dev->port->ha;
+	struct Scsi_Host *shost = sas_ha->core.shost;
+	struct sas_internal *i = to_sas_internal(shost->transportt);
+
+	if (!i->dft->lldd_dev_gone)
+		return;
+
+	if (test_and_clear_bit(SAS_DEV_FOUND, &dev->state)) {
+		i->dft->lldd_dev_gone(dev);
+		sas_put_device(dev);
+	}
+}
+
+static void sas_probe_devices(struct asd_sas_port *port)
+{
+	struct domain_device *dev, *n;
+
+	/* devices must be domain members before link recovery and probe */
+	list_for_each_entry(dev, &port->disco_list, disco_list_node) {
+		spin_lock_irq(&port->dev_list_lock);
+		list_add_tail(&dev->dev_list_node, &port->dev_list);
+		spin_unlock_irq(&port->dev_list_lock);
+	}
+
+	sas_probe_sata(port);
+
+	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
+		int err;
+
+		err = sas_rphy_add(dev->rphy);
+		if (err)
+			sas_fail_probe(dev, __func__, err);
+		else
+			list_del_init(&dev->disco_list_node);
+	}
+}
+
+static void sas_suspend_devices(struct work_struct *work)
+{
+	struct asd_sas_phy *phy;
+	struct domain_device *dev;
+	struct sas_discovery_event *ev = to_sas_discovery_event(work);
+	struct asd_sas_port *port = ev->port;
+	struct Scsi_Host *shost = port->ha->core.shost;
+	struct sas_internal *si = to_sas_internal(shost->transportt);
+
+	clear_bit(DISCE_SUSPEND, &port->disc.pending);
+
+	sas_suspend_sata(port);
+
+	/* lldd is free to forget the domain_device across the
+	 * suspension, we force the issue here to keep the reference
+	 * counts aligned
+	 */
+	list_for_each_entry(dev, &port->dev_list, dev_list_node)
+		sas_notify_lldd_dev_gone(dev);
+
+	/* we are suspending, so we know events are disabled and
+	 * phy_list is not being mutated
+	 */
+	list_for_each_entry(phy, &port->phy_list, port_phy_el) {
+		if (si->dft->lldd_port_deformed)
+			si->dft->lldd_port_deformed(phy);
+		phy->suspended = 1;
+		port->suspended = 1;
+	}
+}
+
+static void sas_resume_devices(struct work_struct *work)
+{
+	struct sas_discovery_event *ev = to_sas_discovery_event(work);
+	struct asd_sas_port *port = ev->port;
+
+	clear_bit(DISCE_RESUME, &port->disc.pending);
+
+	sas_resume_sata(port);
+}
+
+/**
+ * sas_discover_end_dev - discover an end device (SSP, etc)
+ * @dev: pointer to domain device of interest
+ *
+ * See comment in sas_discover_sata().
+ */
+int sas_discover_end_dev(struct domain_device *dev)
+{
+	return sas_notify_lldd_dev_found(dev);
+}
+
+/* ---------- Device registration and unregistration ---------- */
+
+void sas_free_device(struct kref *kref)
+{
+	struct domain_device *dev = container_of(kref, typeof(*dev), kref);
+
+	put_device(&dev->rphy->dev);
+	dev->rphy = NULL;
+
+	if (dev->parent)
+		sas_put_device(dev->parent);
+
+	sas_port_put_phy(dev->phy);
+	dev->phy = NULL;
+
+	/* remove the phys and ports, everything else should be gone */
+	if (dev_is_expander(dev->dev_type))
+		kfree(dev->ex_dev.ex_phy);
+
+	if (dev_is_sata(dev) && dev->sata_dev.ap) {
+		ata_sas_tport_delete(dev->sata_dev.ap);
+		ata_sas_port_destroy(dev->sata_dev.ap);
+		ata_host_put(dev->sata_dev.ata_host);
+		dev->sata_dev.ata_host = NULL;
+		dev->sata_dev.ap = NULL;
+	}
+
+	kfree(dev);
+}
+
+static void sas_unregister_common_dev(struct asd_sas_port *port, struct domain_device *dev)
+{
+	struct sas_ha_struct *ha = port->ha;
+
+	sas_notify_lldd_dev_gone(dev);
+	if (!dev->parent)
+		dev->port->port_dev = NULL;
+	else
+		list_del_init(&dev->siblings);
+
+	spin_lock_irq(&port->dev_list_lock);
+	list_del_init(&dev->dev_list_node);
+	if (dev_is_sata(dev))
+		sas_ata_end_eh(dev->sata_dev.ap);
+	spin_unlock_irq(&port->dev_list_lock);
+
+	spin_lock_irq(&ha->lock);
+	if (dev->dev_type == SAS_END_DEVICE &&
+	    !list_empty(&dev->ssp_dev.eh_list_node)) {
+		list_del_init(&dev->ssp_dev.eh_list_node);
+		ha->eh_active--;
+	}
+	spin_unlock_irq(&ha->lock);
+
+	sas_put_device(dev);
+}
+
+void sas_destruct_devices(struct asd_sas_port *port)
+{
+	struct domain_device *dev, *n;
+
+	list_for_each_entry_safe(dev, n, &port->destroy_list, disco_list_node) {
+		list_del_init(&dev->disco_list_node);
+
+		sas_remove_children(&dev->rphy->dev);
+		sas_rphy_delete(dev->rphy);
+		sas_unregister_common_dev(port, dev);
+	}
+}
+
+static void sas_destruct_ports(struct asd_sas_port *port)
+{
+	struct sas_port *sas_port, *p;
+
+	list_for_each_entry_safe(sas_port, p, &port->sas_port_del_list, del_list) {
+		list_del_init(&sas_port->del_list);
+		sas_port_delete(sas_port);
+	}
+}
+
+void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev)
+{
+	if (!test_bit(SAS_DEV_DESTROY, &dev->state) &&
+	    !list_empty(&dev->disco_list_node)) {
+		/* this rphy never saw sas_rphy_add */
+		list_del_init(&dev->disco_list_node);
+		sas_rphy_free(dev->rphy);
+		sas_unregister_common_dev(port, dev);
+		return;
+	}
+
+	if (!test_and_set_bit(SAS_DEV_DESTROY, &dev->state)) {
+		sas_rphy_unlink(dev->rphy);
+		list_move_tail(&dev->disco_list_node, &port->destroy_list);
+	}
+}
+
+void sas_unregister_domain_devices(struct asd_sas_port *port, int gone)
+{
+	struct domain_device *dev, *n;
+
+	list_for_each_entry_safe_reverse(dev, n, &port->dev_list, dev_list_node) {
+		if (gone)
+			set_bit(SAS_DEV_GONE, &dev->state);
+		sas_unregister_dev(port, dev);
+	}
+
+	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node)
+		sas_unregister_dev(port, dev);
+
+	port->port->rphy = NULL;
+
+}
+
+void sas_device_set_phy(struct domain_device *dev, struct sas_port *port)
+{
+	struct sas_ha_struct *ha;
+	struct sas_phy *new_phy;
+
+	if (!dev)
+		return;
+
+	ha = dev->port->ha;
+	new_phy = sas_port_get_phy(port);
+
+	/* pin and record last seen phy */
+	spin_lock_irq(&ha->phy_port_lock);
+	if (new_phy) {
+		sas_port_put_phy(dev->phy);
+		dev->phy = new_phy;
+	}
+	spin_unlock_irq(&ha->phy_port_lock);
+}
+
+/* ---------- Discovery and Revalidation ---------- */
+
+/**
+ * sas_discover_domain - discover the domain
+ * @work: work structure embedded in 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.
+ */
+static void sas_discover_domain(struct work_struct *work)
+{
+	struct domain_device *dev;
+	int error = 0;
+	struct sas_discovery_event *ev = to_sas_discovery_event(work);
+	struct asd_sas_port *port = ev->port;
+
+	clear_bit(DISCE_DISCOVER_DOMAIN, &port->disc.pending);
+
+	if (port->port_dev)
+		return;
+
+	error = sas_get_port_device(port);
+	if (error)
+		return;
+	dev = port->port_dev;
+
+	pr_debug("DOING DISCOVERY on port %d, pid:%d\n", port->id,
+		 task_pid_nr(current));
+
+	switch (dev->dev_type) {
+	case SAS_END_DEVICE:
+		error = sas_discover_end_dev(dev);
+		break;
+	case SAS_EDGE_EXPANDER_DEVICE:
+	case SAS_FANOUT_EXPANDER_DEVICE:
+		error = sas_discover_root_expander(dev);
+		break;
+	case SAS_SATA_DEV:
+	case SAS_SATA_PM:
+#ifdef CONFIG_SCSI_SAS_ATA
+		error = sas_discover_sata(dev);
+		break;
+#else
+		pr_notice("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
+		/* Fall through */
+#endif
+		/* Fall through - only for the #else condition above. */
+	default:
+		error = -ENXIO;
+		pr_err("unhandled device %d\n", dev->dev_type);
+		break;
+	}
+
+	if (error) {
+		sas_rphy_free(dev->rphy);
+		list_del_init(&dev->disco_list_node);
+		spin_lock_irq(&port->dev_list_lock);
+		list_del_init(&dev->dev_list_node);
+		spin_unlock_irq(&port->dev_list_lock);
+
+		sas_put_device(dev);
+		port->port_dev = NULL;
+	}
+
+	sas_probe_devices(port);
+
+	pr_debug("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
+		 task_pid_nr(current), error);
+}
+
+static void sas_revalidate_domain(struct work_struct *work)
+{
+	int res = 0;
+	struct sas_discovery_event *ev = to_sas_discovery_event(work);
+	struct asd_sas_port *port = ev->port;
+	struct sas_ha_struct *ha = port->ha;
+	struct domain_device *ddev = port->port_dev;
+
+	/* prevent revalidation from finding sata links in recovery */
+	mutex_lock(&ha->disco_mutex);
+	if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
+		pr_debug("REVALIDATION DEFERRED on port %d, pid:%d\n",
+			 port->id, task_pid_nr(current));
+		goto out;
+	}
+
+	clear_bit(DISCE_REVALIDATE_DOMAIN, &port->disc.pending);
+
+	pr_debug("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
+		 task_pid_nr(current));
+
+	if (ddev && dev_is_expander(ddev->dev_type))
+		res = sas_ex_revalidate_domain(ddev);
+
+	pr_debug("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
+		 port->id, task_pid_nr(current), res);
+ out:
+	mutex_unlock(&ha->disco_mutex);
+
+	sas_destruct_devices(port);
+	sas_destruct_ports(port);
+	sas_probe_devices(port);
+}
+
+/* ---------- Events ---------- */
+
+static void sas_chain_work(struct sas_ha_struct *ha, struct sas_work *sw)
+{
+	/* chained work is not subject to SA_HA_DRAINING or
+	 * SAS_HA_REGISTERED, because it is either submitted in the
+	 * workqueue, or known to be submitted from a context that is
+	 * not racing against draining
+	 */
+	queue_work(ha->disco_q, &sw->work);
+}
+
+static void sas_chain_event(int event, unsigned long *pending,
+			    struct sas_work *sw,
+			    struct sas_ha_struct *ha)
+{
+	if (!test_and_set_bit(event, pending)) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&ha->lock, flags);
+		sas_chain_work(ha, sw);
+		spin_unlock_irqrestore(&ha->lock, flags);
+	}
+}
+
+int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
+{
+	struct sas_discovery *disc;
+
+	if (!port)
+		return 0;
+	disc = &port->disc;
+
+	BUG_ON(ev >= DISC_NUM_EVENTS);
+
+	sas_chain_event(ev, &disc->pending, &disc->disc_work[ev].work, port->ha);
+
+	return 0;
+}
+
+/**
+ * sas_init_disc - initialize the discovery struct in the port
+ * @disc: port discovery structure
+ * @port: pointer to struct port
+ *
+ * Called when the ports are being initialized.
+ */
+void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port)
+{
+	int i;
+
+	static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
+		[DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
+		[DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
+		[DISCE_SUSPEND] = sas_suspend_devices,
+		[DISCE_RESUME] = sas_resume_devices,
+	};
+
+	disc->pending = 0;
+	for (i = 0; i < DISC_NUM_EVENTS; i++) {
+		INIT_SAS_WORK(&disc->disc_work[i].work, sas_event_fns[i]);
+		disc->disc_work[i].port = port;
+	}
+}
diff --git a/drivers/scsi/libsas/sas_event.c b/drivers/scsi/libsas/sas_event.c
new file mode 100644
index 000000000..ba266a172
--- /dev/null
+++ b/drivers/scsi/libsas/sas_event.c
@@ -0,0 +1,218 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Serial Attached SCSI (SAS) Event processing
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+ */
+
+#include <linux/export.h>
+#include <scsi/scsi_host.h>
+#include "sas_internal.h"
+
+int sas_queue_work(struct sas_ha_struct *ha, struct sas_work *sw)
+{
+	/* it's added to the defer_q when draining so return succeed */
+	int rc = 1;
+
+	if (!test_bit(SAS_HA_REGISTERED, &ha->state))
+		return 0;
+
+	if (test_bit(SAS_HA_DRAINING, &ha->state)) {
+		/* add it to the defer list, if not already pending */
+		if (list_empty(&sw->drain_node))
+			list_add_tail(&sw->drain_node, &ha->defer_q);
+	} else
+		rc = queue_work(ha->event_q, &sw->work);
+
+	return rc;
+}
+
+static int sas_queue_event(int event, struct sas_work *work,
+			    struct sas_ha_struct *ha)
+{
+	unsigned long flags;
+	int rc;
+
+	spin_lock_irqsave(&ha->lock, flags);
+	rc = sas_queue_work(ha, work);
+	spin_unlock_irqrestore(&ha->lock, flags);
+
+	return rc;
+}
+
+
+void __sas_drain_work(struct sas_ha_struct *ha)
+{
+	struct sas_work *sw, *_sw;
+	int ret;
+
+	set_bit(SAS_HA_DRAINING, &ha->state);
+	/* flush submitters */
+	spin_lock_irq(&ha->lock);
+	spin_unlock_irq(&ha->lock);
+
+	drain_workqueue(ha->event_q);
+	drain_workqueue(ha->disco_q);
+
+	spin_lock_irq(&ha->lock);
+	clear_bit(SAS_HA_DRAINING, &ha->state);
+	list_for_each_entry_safe(sw, _sw, &ha->defer_q, drain_node) {
+		list_del_init(&sw->drain_node);
+		ret = sas_queue_work(ha, sw);
+		if (ret != 1)
+			sas_free_event(to_asd_sas_event(&sw->work));
+
+	}
+	spin_unlock_irq(&ha->lock);
+}
+
+int sas_drain_work(struct sas_ha_struct *ha)
+{
+	int err;
+
+	err = mutex_lock_interruptible(&ha->drain_mutex);
+	if (err)
+		return err;
+	if (test_bit(SAS_HA_REGISTERED, &ha->state))
+		__sas_drain_work(ha);
+	mutex_unlock(&ha->drain_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(sas_drain_work);
+
+void sas_disable_revalidation(struct sas_ha_struct *ha)
+{
+	mutex_lock(&ha->disco_mutex);
+	set_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state);
+	mutex_unlock(&ha->disco_mutex);
+}
+
+void sas_enable_revalidation(struct sas_ha_struct *ha)
+{
+	int i;
+
+	mutex_lock(&ha->disco_mutex);
+	clear_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state);
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_port *port = ha->sas_port[i];
+		const int ev = DISCE_REVALIDATE_DOMAIN;
+		struct sas_discovery *d = &port->disc;
+		struct asd_sas_phy *sas_phy;
+
+		if (!test_and_clear_bit(ev, &d->pending))
+			continue;
+
+		if (list_empty(&port->phy_list))
+			continue;
+
+		sas_phy = container_of(port->phy_list.next, struct asd_sas_phy,
+				port_phy_el);
+		sas_notify_port_event(sas_phy, PORTE_BROADCAST_RCVD);
+	}
+	mutex_unlock(&ha->disco_mutex);
+}
+
+
+static void sas_port_event_worker(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+
+	sas_port_event_fns[ev->event](work);
+	sas_free_event(ev);
+}
+
+static void sas_phy_event_worker(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+
+	sas_phy_event_fns[ev->event](work);
+	sas_free_event(ev);
+}
+
+static int __sas_notify_port_event(struct asd_sas_phy *phy,
+				   enum port_event event,
+				   struct asd_sas_event *ev)
+{
+	struct sas_ha_struct *ha = phy->ha;
+	int ret;
+
+	BUG_ON(event >= PORT_NUM_EVENTS);
+
+	INIT_SAS_EVENT(ev, sas_port_event_worker, phy, event);
+
+	ret = sas_queue_event(event, &ev->work, ha);
+	if (ret != 1)
+		sas_free_event(ev);
+
+	return ret;
+}
+
+int sas_notify_port_event_gfp(struct asd_sas_phy *phy, enum port_event event,
+			      gfp_t gfp_flags)
+{
+	struct asd_sas_event *ev;
+
+	ev = sas_alloc_event_gfp(phy, gfp_flags);
+	if (!ev)
+		return -ENOMEM;
+
+	return __sas_notify_port_event(phy, event, ev);
+}
+EXPORT_SYMBOL_GPL(sas_notify_port_event_gfp);
+
+int sas_notify_port_event(struct asd_sas_phy *phy, enum port_event event)
+{
+	struct asd_sas_event *ev;
+
+	ev = sas_alloc_event(phy);
+	if (!ev)
+		return -ENOMEM;
+
+	return __sas_notify_port_event(phy, event, ev);
+}
+EXPORT_SYMBOL_GPL(sas_notify_port_event);
+
+static inline int __sas_notify_phy_event(struct asd_sas_phy *phy,
+					 enum phy_event event,
+					 struct asd_sas_event *ev)
+{
+	struct sas_ha_struct *ha = phy->ha;
+	int ret;
+
+	BUG_ON(event >= PHY_NUM_EVENTS);
+
+	INIT_SAS_EVENT(ev, sas_phy_event_worker, phy, event);
+
+	ret = sas_queue_event(event, &ev->work, ha);
+	if (ret != 1)
+		sas_free_event(ev);
+
+	return ret;
+}
+
+int sas_notify_phy_event_gfp(struct asd_sas_phy *phy, enum phy_event event,
+			     gfp_t gfp_flags)
+{
+	struct asd_sas_event *ev;
+
+	ev = sas_alloc_event_gfp(phy, gfp_flags);
+	if (!ev)
+		return -ENOMEM;
+
+	return __sas_notify_phy_event(phy, event, ev);
+}
+EXPORT_SYMBOL_GPL(sas_notify_phy_event_gfp);
+
+int sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event)
+{
+	struct asd_sas_event *ev;
+
+	ev = sas_alloc_event(phy);
+	if (!ev)
+		return -ENOMEM;
+
+	return __sas_notify_phy_event(phy, event, ev);
+}
+EXPORT_SYMBOL_GPL(sas_notify_phy_event);
diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c
new file mode 100644
index 000000000..8444a4287
--- /dev/null
+++ b/drivers/scsi/libsas/sas_expander.c
@@ -0,0 +1,2181 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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.
+ */
+
+#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_sync(&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 == SAS_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;
+
+	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 %016llx 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 %016llx 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);
+			return res;
+		} 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)
+		pr_notice("ex %016llx phy%02d failed to discover\n",
+			  SAS_ADDR(dev->sas_addr), phy_id);
+	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 (dev_is_expander(phy->attached_dev_type) &&
+		    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 (!dev_is_expander(child->dev_type))
+			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 (dev_is_expander(phy->attached_dev_type) &&
+		    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 (!dev_is_expander(child->parent->dev_type))
+		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_is_expander(dev->dev_type)) {
+			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 (dev_is_expander(ch->dev_type)) {
+			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 (dev_is_expander(child->dev_type))
+			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 (dev_is_expander(child->dev_type))
+					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 (dev_is_expander(child->dev_type)) {
+			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 (dev_is_expander(child->dev_type))
+				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);
+}
diff --git a/drivers/scsi/libsas/sas_host_smp.c b/drivers/scsi/libsas/sas_host_smp.c
new file mode 100644
index 000000000..eca2a6bf3
--- /dev/null
+++ b/drivers/scsi/libsas/sas_host_smp.c
@@ -0,0 +1,354 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Serial Attached SCSI (SAS) Expander discovery and configuration
+ *
+ * Copyright (C) 2007 James E.J. Bottomley
+ *		<James.Bottomley@HansenPartnership.com>
+ */
+#include <linux/scatterlist.h>
+#include <linux/blkdev.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+#include "sas_internal.h"
+
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_sas.h>
+#include "../scsi_sas_internal.h"
+
+static void sas_host_smp_discover(struct sas_ha_struct *sas_ha, u8 *resp_data,
+				  u8 phy_id)
+{
+	struct sas_phy *phy;
+	struct sas_rphy *rphy;
+
+	if (phy_id >= sas_ha->num_phys) {
+		resp_data[2] = SMP_RESP_NO_PHY;
+		return;
+	}
+	resp_data[2] = SMP_RESP_FUNC_ACC;
+
+	phy = sas_ha->sas_phy[phy_id]->phy;
+	resp_data[9] = phy_id;
+	resp_data[13] = phy->negotiated_linkrate;
+	memcpy(resp_data + 16, sas_ha->sas_addr, SAS_ADDR_SIZE);
+	memcpy(resp_data + 24, sas_ha->sas_phy[phy_id]->attached_sas_addr,
+	       SAS_ADDR_SIZE);
+	resp_data[40] = (phy->minimum_linkrate << 4) |
+		phy->minimum_linkrate_hw;
+	resp_data[41] = (phy->maximum_linkrate << 4) |
+		phy->maximum_linkrate_hw;
+
+	if (!sas_ha->sas_phy[phy_id]->port ||
+	    !sas_ha->sas_phy[phy_id]->port->port_dev)
+		return;
+
+	rphy = sas_ha->sas_phy[phy_id]->port->port_dev->rphy;
+	resp_data[12] = rphy->identify.device_type << 4;
+	resp_data[14] = rphy->identify.initiator_port_protocols;
+	resp_data[15] = rphy->identify.target_port_protocols;
+}
+
+/**
+ * to_sas_gpio_gp_bit - given the gpio frame data find the byte/bit position of 'od'
+ * @od: od bit to find
+ * @data: incoming bitstream (from frame)
+ * @index: requested data register index (from frame)
+ * @count: total number of registers in the bitstream (from frame)
+ * @bit: bit position of 'od' in the returned byte
+ *
+ * returns NULL if 'od' is not in 'data'
+ *
+ * From SFF-8485 v0.7:
+ * "In GPIO_TX[1], bit 0 of byte 3 contains the first bit (i.e., OD0.0)
+ *  and bit 7 of byte 0 contains the 32nd bit (i.e., OD10.1).
+ *
+ *  In GPIO_TX[2], bit 0 of byte 3 contains the 33rd bit (i.e., OD10.2)
+ *  and bit 7 of byte 0 contains the 64th bit (i.e., OD21.0)."
+ *
+ * The general-purpose (raw-bitstream) RX registers have the same layout
+ * although 'od' is renamed 'id' for 'input data'.
+ *
+ * SFF-8489 defines the behavior of the LEDs in response to the 'od' values.
+ */
+static u8 *to_sas_gpio_gp_bit(unsigned int od, u8 *data, u8 index, u8 count, u8 *bit)
+{
+	unsigned int reg;
+	u8 byte;
+
+	/* gp registers start at index 1 */
+	if (index == 0)
+		return NULL;
+
+	index--; /* make index 0-based */
+	if (od < index * 32)
+		return NULL;
+
+	od -= index * 32;
+	reg = od >> 5;
+
+	if (reg >= count)
+		return NULL;
+
+	od &= (1 << 5) - 1;
+	byte = 3 - (od >> 3);
+	*bit = od & ((1 << 3) - 1);
+
+	return &data[reg * 4 + byte];
+}
+
+int try_test_sas_gpio_gp_bit(unsigned int od, u8 *data, u8 index, u8 count)
+{
+	u8 *byte;
+	u8 bit;
+
+	byte = to_sas_gpio_gp_bit(od, data, index, count, &bit);
+	if (!byte)
+		return -1;
+
+	return (*byte >> bit) & 1;
+}
+EXPORT_SYMBOL(try_test_sas_gpio_gp_bit);
+
+static int sas_host_smp_write_gpio(struct sas_ha_struct *sas_ha, u8 *resp_data,
+				   u8 reg_type, u8 reg_index, u8 reg_count,
+				   u8 *req_data)
+{
+	struct sas_internal *i = to_sas_internal(sas_ha->core.shost->transportt);
+	int written;
+
+	if (i->dft->lldd_write_gpio == NULL) {
+		resp_data[2] = SMP_RESP_FUNC_UNK;
+		return 0;
+	}
+
+	written = i->dft->lldd_write_gpio(sas_ha, reg_type, reg_index,
+					  reg_count, req_data);
+
+	if (written < 0) {
+		resp_data[2] = SMP_RESP_FUNC_FAILED;
+		written = 0;
+	} else
+		resp_data[2] = SMP_RESP_FUNC_ACC;
+
+	return written;
+}
+
+static void sas_report_phy_sata(struct sas_ha_struct *sas_ha, u8 *resp_data,
+				u8 phy_id)
+{
+	struct sas_rphy *rphy;
+	struct dev_to_host_fis *fis;
+	int i;
+
+	if (phy_id >= sas_ha->num_phys) {
+		resp_data[2] = SMP_RESP_NO_PHY;
+		return;
+	}
+
+	resp_data[2] = SMP_RESP_PHY_NO_SATA;
+
+	if (!sas_ha->sas_phy[phy_id]->port)
+		return;
+
+	rphy = sas_ha->sas_phy[phy_id]->port->port_dev->rphy;
+	fis = (struct dev_to_host_fis *)
+		sas_ha->sas_phy[phy_id]->port->port_dev->frame_rcvd;
+	if (rphy->identify.target_port_protocols != SAS_PROTOCOL_SATA)
+		return;
+
+	resp_data[2] = SMP_RESP_FUNC_ACC;
+	resp_data[9] = phy_id;
+	memcpy(resp_data + 16, sas_ha->sas_phy[phy_id]->attached_sas_addr,
+	       SAS_ADDR_SIZE);
+
+	/* check to see if we have a valid d2h fis */
+	if (fis->fis_type != 0x34)
+		return;
+
+	/* the d2h fis is required by the standard to be in LE format */
+	for (i = 0; i < 20; i += 4) {
+		u8 *dst = resp_data + 24 + i, *src =
+			&sas_ha->sas_phy[phy_id]->port->port_dev->frame_rcvd[i];
+		dst[0] = src[3];
+		dst[1] = src[2];
+		dst[2] = src[1];
+		dst[3] = src[0];
+	}
+}
+
+static void sas_phy_control(struct sas_ha_struct *sas_ha, u8 phy_id,
+			    u8 phy_op, enum sas_linkrate min,
+			    enum sas_linkrate max, u8 *resp_data)
+{
+	struct sas_internal *i =
+		to_sas_internal(sas_ha->core.shost->transportt);
+	struct sas_phy_linkrates rates;
+	struct asd_sas_phy *asd_phy;
+
+	if (phy_id >= sas_ha->num_phys) {
+		resp_data[2] = SMP_RESP_NO_PHY;
+		return;
+	}
+
+	asd_phy = sas_ha->sas_phy[phy_id];
+	switch (phy_op) {
+	case PHY_FUNC_NOP:
+	case PHY_FUNC_LINK_RESET:
+	case PHY_FUNC_HARD_RESET:
+	case PHY_FUNC_DISABLE:
+	case PHY_FUNC_CLEAR_ERROR_LOG:
+	case PHY_FUNC_CLEAR_AFFIL:
+	case PHY_FUNC_TX_SATA_PS_SIGNAL:
+		break;
+
+	default:
+		resp_data[2] = SMP_RESP_PHY_UNK_OP;
+		return;
+	}
+
+	rates.minimum_linkrate = min;
+	rates.maximum_linkrate = max;
+
+	/* filter reset requests through libata eh */
+	if (phy_op == PHY_FUNC_LINK_RESET && sas_try_ata_reset(asd_phy) == 0) {
+		resp_data[2] = SMP_RESP_FUNC_ACC;
+		return;
+	}
+
+	if (i->dft->lldd_control_phy(asd_phy, phy_op, &rates))
+		resp_data[2] = SMP_RESP_FUNC_FAILED;
+	else
+		resp_data[2] = SMP_RESP_FUNC_ACC;
+}
+
+void sas_smp_host_handler(struct bsg_job *job, struct Scsi_Host *shost)
+{
+	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+	u8 *req_data, *resp_data;
+	unsigned int reslen = 0;
+	int error = -EINVAL;
+
+	/* eight is the minimum size for request and response frames */
+	if (job->request_payload.payload_len < 8 ||
+	    job->reply_payload.payload_len < 8)
+		goto out;
+
+	error = -ENOMEM;
+	req_data = kzalloc(job->request_payload.payload_len, GFP_KERNEL);
+	if (!req_data)
+		goto out;
+	sg_copy_to_buffer(job->request_payload.sg_list,
+			  job->request_payload.sg_cnt, req_data,
+			  job->request_payload.payload_len);
+
+	/* make sure frame can always be built ... we copy
+	 * back only the requested length */
+	resp_data = kzalloc(max(job->reply_payload.payload_len, 128U),
+			GFP_KERNEL);
+	if (!resp_data)
+		goto out_free_req;
+
+	error = -EINVAL;
+	if (req_data[0] != SMP_REQUEST)
+		goto out_free_resp;
+
+	/* set up default don't know response */
+	resp_data[0] = SMP_RESPONSE;
+	resp_data[1] = req_data[1];
+	resp_data[2] = SMP_RESP_FUNC_UNK;
+
+	switch (req_data[1]) {
+	case SMP_REPORT_GENERAL:
+		resp_data[2] = SMP_RESP_FUNC_ACC;
+		resp_data[9] = sas_ha->num_phys;
+		reslen = 32;
+		break;
+
+	case SMP_REPORT_MANUF_INFO:
+		resp_data[2] = SMP_RESP_FUNC_ACC;
+		memcpy(resp_data + 12, shost->hostt->name,
+		       SAS_EXPANDER_VENDOR_ID_LEN);
+		memcpy(resp_data + 20, "libsas virt phy",
+		       SAS_EXPANDER_PRODUCT_ID_LEN);
+		reslen = 64;
+		break;
+
+	case SMP_READ_GPIO_REG:
+		/* FIXME: need GPIO support in the transport class */
+		break;
+
+	case SMP_DISCOVER:
+		if (job->request_payload.payload_len < 16)
+			goto out_free_resp;
+		sas_host_smp_discover(sas_ha, resp_data, req_data[9]);
+		reslen = 56;
+		break;
+
+	case SMP_REPORT_PHY_ERR_LOG:
+		/* FIXME: could implement this with additional
+		 * libsas callbacks providing the HW supports it */
+		break;
+
+	case SMP_REPORT_PHY_SATA:
+		if (job->request_payload.payload_len < 16)
+			goto out_free_resp;
+		sas_report_phy_sata(sas_ha, resp_data, req_data[9]);
+		reslen = 60;
+		break;
+
+	case SMP_REPORT_ROUTE_INFO:
+		/* Can't implement; hosts have no routes */
+		break;
+
+	case SMP_WRITE_GPIO_REG: {
+		/* SFF-8485 v0.7 */
+		const int base_frame_size = 11;
+		int to_write = req_data[4];
+
+		if (job->request_payload.payload_len <
+				base_frame_size + to_write * 4) {
+			resp_data[2] = SMP_RESP_INV_FRM_LEN;
+			break;
+		}
+
+		to_write = sas_host_smp_write_gpio(sas_ha, resp_data, req_data[2],
+						   req_data[3], to_write, &req_data[8]);
+		reslen = 8;
+		break;
+	}
+
+	case SMP_CONF_ROUTE_INFO:
+		/* Can't implement; hosts have no routes */
+		break;
+
+	case SMP_PHY_CONTROL:
+		if (job->request_payload.payload_len < 44)
+			goto out_free_resp;
+		sas_phy_control(sas_ha, req_data[9], req_data[10],
+				req_data[32] >> 4, req_data[33] >> 4,
+				resp_data);
+		reslen = 8;
+		break;
+
+	case SMP_PHY_TEST_FUNCTION:
+		/* FIXME: should this be implemented? */
+		break;
+
+	default:
+		/* probably a 2.0 function */
+		break;
+	}
+
+	sg_copy_from_buffer(job->reply_payload.sg_list,
+			    job->reply_payload.sg_cnt, resp_data,
+			    job->reply_payload.payload_len);
+
+	error = 0;
+out_free_resp:
+	kfree(resp_data);
+out_free_req:
+	kfree(req_data);
+out:
+	bsg_job_done(job, error, reslen);
+}
diff --git a/drivers/scsi/libsas/sas_init.c b/drivers/scsi/libsas/sas_init.c
new file mode 100644
index 000000000..f8ae1f0f1
--- /dev/null
+++ b/drivers/scsi/libsas/sas_init.c
@@ -0,0 +1,673 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Serial Attached SCSI (SAS) Transport Layer initialization
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/spinlock.h>
+#include <scsi/sas_ata.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_sas.h>
+
+#include "sas_internal.h"
+
+#include "../scsi_sas_internal.h"
+
+static struct kmem_cache *sas_task_cache;
+static struct kmem_cache *sas_event_cache;
+
+struct sas_task *sas_alloc_task(gfp_t flags)
+{
+	struct sas_task *task = kmem_cache_zalloc(sas_task_cache, flags);
+
+	if (task) {
+		spin_lock_init(&task->task_state_lock);
+		task->task_state_flags = SAS_TASK_STATE_PENDING;
+	}
+
+	return task;
+}
+EXPORT_SYMBOL_GPL(sas_alloc_task);
+
+struct sas_task *sas_alloc_slow_task(gfp_t flags)
+{
+	struct sas_task *task = sas_alloc_task(flags);
+	struct sas_task_slow *slow = kmalloc(sizeof(*slow), flags);
+
+	if (!task || !slow) {
+		if (task)
+			kmem_cache_free(sas_task_cache, task);
+		kfree(slow);
+		return NULL;
+	}
+
+	task->slow_task = slow;
+	slow->task = task;
+	timer_setup(&slow->timer, NULL, 0);
+	init_completion(&slow->completion);
+
+	return task;
+}
+EXPORT_SYMBOL_GPL(sas_alloc_slow_task);
+
+void sas_free_task(struct sas_task *task)
+{
+	if (task) {
+		kfree(task->slow_task);
+		kmem_cache_free(sas_task_cache, task);
+	}
+}
+EXPORT_SYMBOL_GPL(sas_free_task);
+
+/*------------ SAS addr hash -----------*/
+void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
+{
+	const u32 poly = 0x00DB2777;
+	u32 r = 0;
+	int i;
+
+	for (i = 0; i < SAS_ADDR_SIZE; i++) {
+		int b;
+
+		for (b = (SAS_ADDR_SIZE - 1); b >= 0; b--) {
+			r <<= 1;
+			if ((1 << b) & sas_addr[i]) {
+				if (!(r & 0x01000000))
+					r ^= poly;
+			} else if (r & 0x01000000) {
+				r ^= poly;
+			}
+		}
+	}
+
+	hashed[0] = (r >> 16) & 0xFF;
+	hashed[1] = (r >> 8) & 0xFF;
+	hashed[2] = r & 0xFF;
+}
+
+int sas_register_ha(struct sas_ha_struct *sas_ha)
+{
+	char name[64];
+	int error = 0;
+
+	mutex_init(&sas_ha->disco_mutex);
+	spin_lock_init(&sas_ha->phy_port_lock);
+	sas_hash_addr(sas_ha->hashed_sas_addr, sas_ha->sas_addr);
+
+	set_bit(SAS_HA_REGISTERED, &sas_ha->state);
+	spin_lock_init(&sas_ha->lock);
+	mutex_init(&sas_ha->drain_mutex);
+	init_waitqueue_head(&sas_ha->eh_wait_q);
+	INIT_LIST_HEAD(&sas_ha->defer_q);
+	INIT_LIST_HEAD(&sas_ha->eh_dev_q);
+
+	sas_ha->event_thres = SAS_PHY_SHUTDOWN_THRES;
+
+	error = sas_register_phys(sas_ha);
+	if (error) {
+		pr_notice("couldn't register sas phys:%d\n", error);
+		return error;
+	}
+
+	error = sas_register_ports(sas_ha);
+	if (error) {
+		pr_notice("couldn't register sas ports:%d\n", error);
+		goto Undo_phys;
+	}
+
+	error = -ENOMEM;
+	snprintf(name, sizeof(name), "%s_event_q", dev_name(sas_ha->dev));
+	sas_ha->event_q = create_singlethread_workqueue(name);
+	if (!sas_ha->event_q)
+		goto Undo_ports;
+
+	snprintf(name, sizeof(name), "%s_disco_q", dev_name(sas_ha->dev));
+	sas_ha->disco_q = create_singlethread_workqueue(name);
+	if (!sas_ha->disco_q)
+		goto Undo_event_q;
+
+	INIT_LIST_HEAD(&sas_ha->eh_done_q);
+	INIT_LIST_HEAD(&sas_ha->eh_ata_q);
+
+	return 0;
+
+Undo_event_q:
+	destroy_workqueue(sas_ha->event_q);
+Undo_ports:
+	sas_unregister_ports(sas_ha);
+Undo_phys:
+
+	return error;
+}
+
+static void sas_disable_events(struct sas_ha_struct *sas_ha)
+{
+	/* Set the state to unregistered to avoid further unchained
+	 * events to be queued, and flush any in-progress drainers
+	 */
+	mutex_lock(&sas_ha->drain_mutex);
+	spin_lock_irq(&sas_ha->lock);
+	clear_bit(SAS_HA_REGISTERED, &sas_ha->state);
+	spin_unlock_irq(&sas_ha->lock);
+	__sas_drain_work(sas_ha);
+	mutex_unlock(&sas_ha->drain_mutex);
+}
+
+int sas_unregister_ha(struct sas_ha_struct *sas_ha)
+{
+	sas_disable_events(sas_ha);
+	sas_unregister_ports(sas_ha);
+
+	/* flush unregistration work */
+	mutex_lock(&sas_ha->drain_mutex);
+	__sas_drain_work(sas_ha);
+	mutex_unlock(&sas_ha->drain_mutex);
+
+	destroy_workqueue(sas_ha->disco_q);
+	destroy_workqueue(sas_ha->event_q);
+
+	return 0;
+}
+
+static int sas_get_linkerrors(struct sas_phy *phy)
+{
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		return i->dft->lldd_control_phy(asd_phy, PHY_FUNC_GET_EVENTS, NULL);
+	}
+
+	return sas_smp_get_phy_events(phy);
+}
+
+int sas_try_ata_reset(struct asd_sas_phy *asd_phy)
+{
+	struct domain_device *dev = NULL;
+
+	/* try to route user requested link resets through libata */
+	if (asd_phy->port)
+		dev = asd_phy->port->port_dev;
+
+	/* validate that dev has been probed */
+	if (dev)
+		dev = sas_find_dev_by_rphy(dev->rphy);
+
+	if (dev && dev_is_sata(dev)) {
+		sas_ata_schedule_reset(dev);
+		sas_ata_wait_eh(dev);
+		return 0;
+	}
+
+	return -ENODEV;
+}
+
+/*
+ * transport_sas_phy_reset - reset a phy and permit libata to manage the link
+ *
+ * phy reset request via sysfs in host workqueue context so we know we
+ * can block on eh and safely traverse the domain_device topology
+ */
+static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
+{
+	enum phy_func reset_type;
+
+	if (hard_reset)
+		reset_type = PHY_FUNC_HARD_RESET;
+	else
+		reset_type = PHY_FUNC_LINK_RESET;
+
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		if (!hard_reset && sas_try_ata_reset(asd_phy) == 0)
+			return 0;
+		return i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
+	} else {
+		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
+		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
+		struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
+
+		if (ata_dev && !hard_reset) {
+			sas_ata_schedule_reset(ata_dev);
+			sas_ata_wait_eh(ata_dev);
+			return 0;
+		} else
+			return sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
+	}
+}
+
+static int sas_phy_enable(struct sas_phy *phy, int enable)
+{
+	int ret;
+	enum phy_func cmd;
+
+	if (enable)
+		cmd = PHY_FUNC_LINK_RESET;
+	else
+		cmd = PHY_FUNC_DISABLE;
+
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		if (enable)
+			ret = transport_sas_phy_reset(phy, 0);
+		else
+			ret = i->dft->lldd_control_phy(asd_phy, cmd, NULL);
+	} else {
+		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
+		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
+
+		if (enable)
+			ret = transport_sas_phy_reset(phy, 0);
+		else
+			ret = sas_smp_phy_control(ddev, phy->number, cmd, NULL);
+	}
+	return ret;
+}
+
+int sas_phy_reset(struct sas_phy *phy, int hard_reset)
+{
+	int ret;
+	enum phy_func reset_type;
+
+	if (!phy->enabled)
+		return -ENODEV;
+
+	if (hard_reset)
+		reset_type = PHY_FUNC_HARD_RESET;
+	else
+		reset_type = PHY_FUNC_LINK_RESET;
+
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
+	} else {
+		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
+		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
+		ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
+	}
+	return ret;
+}
+
+int sas_set_phy_speed(struct sas_phy *phy,
+		      struct sas_phy_linkrates *rates)
+{
+	int ret;
+
+	if ((rates->minimum_linkrate &&
+	     rates->minimum_linkrate > phy->maximum_linkrate) ||
+	    (rates->maximum_linkrate &&
+	     rates->maximum_linkrate < phy->minimum_linkrate))
+		return -EINVAL;
+
+	if (rates->minimum_linkrate &&
+	    rates->minimum_linkrate < phy->minimum_linkrate_hw)
+		rates->minimum_linkrate = phy->minimum_linkrate_hw;
+
+	if (rates->maximum_linkrate &&
+	    rates->maximum_linkrate > phy->maximum_linkrate_hw)
+		rates->maximum_linkrate = phy->maximum_linkrate_hw;
+
+	if (scsi_is_sas_phy_local(phy)) {
+		struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+		struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+		struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+		struct sas_internal *i =
+			to_sas_internal(sas_ha->core.shost->transportt);
+
+		ret = i->dft->lldd_control_phy(asd_phy, PHY_FUNC_SET_LINK_RATE,
+					       rates);
+	} else {
+		struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
+		struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
+		ret = sas_smp_phy_control(ddev, phy->number,
+					  PHY_FUNC_LINK_RESET, rates);
+
+	}
+
+	return ret;
+}
+
+void sas_prep_resume_ha(struct sas_ha_struct *ha)
+{
+	int i;
+
+	set_bit(SAS_HA_REGISTERED, &ha->state);
+
+	/* clear out any stale link events/data from the suspension path */
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_phy *phy = ha->sas_phy[i];
+
+		memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);
+		phy->frame_rcvd_size = 0;
+	}
+}
+EXPORT_SYMBOL(sas_prep_resume_ha);
+
+static int phys_suspended(struct sas_ha_struct *ha)
+{
+	int i, rc = 0;
+
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_phy *phy = ha->sas_phy[i];
+
+		if (phy->suspended)
+			rc++;
+	}
+
+	return rc;
+}
+
+void sas_resume_ha(struct sas_ha_struct *ha)
+{
+	const unsigned long tmo = msecs_to_jiffies(25000);
+	int i;
+
+	/* deform ports on phys that did not resume
+	 * at this point we may be racing the phy coming back (as posted
+	 * by the lldd).  So we post the event and once we are in the
+	 * libsas context check that the phy remains suspended before
+	 * tearing it down.
+	 */
+	i = phys_suspended(ha);
+	if (i)
+		dev_info(ha->dev, "waiting up to 25 seconds for %d phy%s to resume\n",
+			 i, i > 1 ? "s" : "");
+	wait_event_timeout(ha->eh_wait_q, phys_suspended(ha) == 0, tmo);
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_phy *phy = ha->sas_phy[i];
+
+		if (phy->suspended) {
+			dev_warn(&phy->phy->dev, "resume timeout\n");
+			sas_notify_phy_event(phy, PHYE_RESUME_TIMEOUT);
+		}
+	}
+
+	/* all phys are back up or timed out, turn on i/o so we can
+	 * flush out disks that did not return
+	 */
+	scsi_unblock_requests(ha->core.shost);
+	sas_drain_work(ha);
+}
+EXPORT_SYMBOL(sas_resume_ha);
+
+void sas_suspend_ha(struct sas_ha_struct *ha)
+{
+	int i;
+
+	sas_disable_events(ha);
+	scsi_block_requests(ha->core.shost);
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_port *port = ha->sas_port[i];
+
+		sas_discover_event(port, DISCE_SUSPEND);
+	}
+
+	/* flush suspend events while unregistered */
+	mutex_lock(&ha->drain_mutex);
+	__sas_drain_work(ha);
+	mutex_unlock(&ha->drain_mutex);
+}
+EXPORT_SYMBOL(sas_suspend_ha);
+
+static void sas_phy_release(struct sas_phy *phy)
+{
+	kfree(phy->hostdata);
+	phy->hostdata = NULL;
+}
+
+static void phy_reset_work(struct work_struct *work)
+{
+	struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
+
+	d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
+}
+
+static void phy_enable_work(struct work_struct *work)
+{
+	struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
+
+	d->enable_result = sas_phy_enable(d->phy, d->enable);
+}
+
+static int sas_phy_setup(struct sas_phy *phy)
+{
+	struct sas_phy_data *d = kzalloc(sizeof(*d), GFP_KERNEL);
+
+	if (!d)
+		return -ENOMEM;
+
+	mutex_init(&d->event_lock);
+	INIT_SAS_WORK(&d->reset_work, phy_reset_work);
+	INIT_SAS_WORK(&d->enable_work, phy_enable_work);
+	d->phy = phy;
+	phy->hostdata = d;
+
+	return 0;
+}
+
+static int queue_phy_reset(struct sas_phy *phy, int hard_reset)
+{
+	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	struct sas_phy_data *d = phy->hostdata;
+	int rc;
+
+	if (!d)
+		return -ENOMEM;
+
+	/* libsas workqueue coordinates ata-eh reset with discovery */
+	mutex_lock(&d->event_lock);
+	d->reset_result = 0;
+	d->hard_reset = hard_reset;
+
+	spin_lock_irq(&ha->lock);
+	sas_queue_work(ha, &d->reset_work);
+	spin_unlock_irq(&ha->lock);
+
+	rc = sas_drain_work(ha);
+	if (rc == 0)
+		rc = d->reset_result;
+	mutex_unlock(&d->event_lock);
+
+	return rc;
+}
+
+static int queue_phy_enable(struct sas_phy *phy, int enable)
+{
+	struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	struct sas_phy_data *d = phy->hostdata;
+	int rc;
+
+	if (!d)
+		return -ENOMEM;
+
+	/* libsas workqueue coordinates ata-eh reset with discovery */
+	mutex_lock(&d->event_lock);
+	d->enable_result = 0;
+	d->enable = enable;
+
+	spin_lock_irq(&ha->lock);
+	sas_queue_work(ha, &d->enable_work);
+	spin_unlock_irq(&ha->lock);
+
+	rc = sas_drain_work(ha);
+	if (rc == 0)
+		rc = d->enable_result;
+	mutex_unlock(&d->event_lock);
+
+	return rc;
+}
+
+static struct sas_function_template sft = {
+	.phy_enable = queue_phy_enable,
+	.phy_reset = queue_phy_reset,
+	.phy_setup = sas_phy_setup,
+	.phy_release = sas_phy_release,
+	.set_phy_speed = sas_set_phy_speed,
+	.get_linkerrors = sas_get_linkerrors,
+	.smp_handler = sas_smp_handler,
+};
+
+static inline ssize_t phy_event_threshold_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
+
+	return scnprintf(buf, PAGE_SIZE, "%u\n", sha->event_thres);
+}
+
+static inline ssize_t phy_event_threshold_store(struct device *dev,
+			struct device_attribute *attr,
+			const char *buf, size_t count)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
+
+	sha->event_thres = simple_strtol(buf, NULL, 10);
+
+	/* threshold cannot be set too small */
+	if (sha->event_thres < 32)
+		sha->event_thres = 32;
+
+	return count;
+}
+
+DEVICE_ATTR(phy_event_threshold,
+	S_IRUGO|S_IWUSR,
+	phy_event_threshold_show,
+	phy_event_threshold_store);
+EXPORT_SYMBOL_GPL(dev_attr_phy_event_threshold);
+
+struct scsi_transport_template *
+sas_domain_attach_transport(struct sas_domain_function_template *dft)
+{
+	struct scsi_transport_template *stt = sas_attach_transport(&sft);
+	struct sas_internal *i;
+
+	if (!stt)
+		return stt;
+
+	i = to_sas_internal(stt);
+	i->dft = dft;
+	stt->create_work_queue = 1;
+	stt->eh_strategy_handler = sas_scsi_recover_host;
+
+	return stt;
+}
+EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
+
+static struct asd_sas_event *__sas_alloc_event(struct asd_sas_phy *phy,
+					       gfp_t gfp_flags)
+{
+	struct asd_sas_event *event;
+	struct sas_ha_struct *sas_ha = phy->ha;
+	struct sas_internal *i =
+		to_sas_internal(sas_ha->core.shost->transportt);
+
+	event = kmem_cache_zalloc(sas_event_cache, gfp_flags);
+	if (!event)
+		return NULL;
+
+	atomic_inc(&phy->event_nr);
+
+	if (atomic_read(&phy->event_nr) > phy->ha->event_thres) {
+		if (i->dft->lldd_control_phy) {
+			if (cmpxchg(&phy->in_shutdown, 0, 1) == 0) {
+				pr_notice("The phy%d bursting events, shut it down.\n",
+					  phy->id);
+				sas_notify_phy_event_gfp(phy, PHYE_SHUTDOWN,
+							 gfp_flags);
+			}
+		} else {
+			/* Do not support PHY control, stop allocating events */
+			WARN_ONCE(1, "PHY control not supported.\n");
+			kmem_cache_free(sas_event_cache, event);
+			atomic_dec(&phy->event_nr);
+			event = NULL;
+		}
+	}
+
+	return event;
+}
+
+struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy)
+{
+	return __sas_alloc_event(phy, in_interrupt() ? GFP_ATOMIC : GFP_KERNEL);
+}
+
+struct asd_sas_event *sas_alloc_event_gfp(struct asd_sas_phy *phy,
+					  gfp_t gfp_flags)
+{
+	return __sas_alloc_event(phy, gfp_flags);
+}
+
+void sas_free_event(struct asd_sas_event *event)
+{
+	struct asd_sas_phy *phy = event->phy;
+
+	kmem_cache_free(sas_event_cache, event);
+	atomic_dec(&phy->event_nr);
+}
+
+/* ---------- SAS Class register/unregister ---------- */
+
+static int __init sas_class_init(void)
+{
+	sas_task_cache = KMEM_CACHE(sas_task, SLAB_HWCACHE_ALIGN);
+	if (!sas_task_cache)
+		goto out;
+
+	sas_event_cache = KMEM_CACHE(asd_sas_event, SLAB_HWCACHE_ALIGN);
+	if (!sas_event_cache)
+		goto free_task_kmem;
+
+	return 0;
+free_task_kmem:
+	kmem_cache_destroy(sas_task_cache);
+out:
+	return -ENOMEM;
+}
+
+static void __exit sas_class_exit(void)
+{
+	kmem_cache_destroy(sas_task_cache);
+	kmem_cache_destroy(sas_event_cache);
+}
+
+MODULE_AUTHOR("Luben Tuikov <luben_tuikov@adaptec.com>");
+MODULE_DESCRIPTION("SAS Transport Layer");
+MODULE_LICENSE("GPL v2");
+
+module_init(sas_class_init);
+module_exit(sas_class_exit);
+
+EXPORT_SYMBOL_GPL(sas_register_ha);
+EXPORT_SYMBOL_GPL(sas_unregister_ha);
diff --git a/drivers/scsi/libsas/sas_internal.h b/drivers/scsi/libsas/sas_internal.h
new file mode 100644
index 000000000..52e09c3e2
--- /dev/null
+++ b/drivers/scsi/libsas/sas_internal.h
@@ -0,0 +1,195 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Serial Attached SCSI (SAS) class internal header file
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+ */
+
+#ifndef _SAS_INTERNAL_H_
+#define _SAS_INTERNAL_H_
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_transport_sas.h>
+#include <scsi/libsas.h>
+#include <scsi/sas_ata.h>
+
+#ifdef pr_fmt
+#undef pr_fmt
+#endif
+
+#define SAS_FMT "sas: "
+
+#define pr_fmt(fmt) SAS_FMT fmt
+
+#define TO_SAS_TASK(_scsi_cmd)  ((void *)(_scsi_cmd)->host_scribble)
+#define ASSIGN_SAS_TASK(_sc, _t) do { (_sc)->host_scribble = (void *) _t; } while (0)
+
+struct sas_phy_data {
+	/* let reset be performed in sas_queue_work() context */
+	struct sas_phy *phy;
+	struct mutex event_lock;
+	int hard_reset;
+	int reset_result;
+	struct sas_work reset_work;
+	int enable;
+	int enable_result;
+	struct sas_work enable_work;
+};
+
+void sas_scsi_recover_host(struct Scsi_Host *shost);
+
+int sas_show_class(enum sas_class class, char *buf);
+int sas_show_proto(enum sas_protocol proto, char *buf);
+int sas_show_linkrate(enum sas_linkrate linkrate, char *buf);
+int sas_show_oob_mode(enum sas_oob_mode oob_mode, char *buf);
+
+int  sas_register_phys(struct sas_ha_struct *sas_ha);
+void sas_unregister_phys(struct sas_ha_struct *sas_ha);
+
+struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy);
+struct asd_sas_event *sas_alloc_event_gfp(struct asd_sas_phy *phy,
+					  gfp_t gfp_flags);
+void sas_free_event(struct asd_sas_event *event);
+
+int  sas_register_ports(struct sas_ha_struct *sas_ha);
+void sas_unregister_ports(struct sas_ha_struct *sas_ha);
+
+void sas_disable_revalidation(struct sas_ha_struct *ha);
+void sas_enable_revalidation(struct sas_ha_struct *ha);
+void __sas_drain_work(struct sas_ha_struct *ha);
+
+void sas_deform_port(struct asd_sas_phy *phy, int gone);
+
+void sas_porte_bytes_dmaed(struct work_struct *work);
+void sas_porte_broadcast_rcvd(struct work_struct *work);
+void sas_porte_link_reset_err(struct work_struct *work);
+void sas_porte_timer_event(struct work_struct *work);
+void sas_porte_hard_reset(struct work_struct *work);
+int sas_queue_work(struct sas_ha_struct *ha, struct sas_work *sw);
+
+int sas_notify_lldd_dev_found(struct domain_device *);
+void sas_notify_lldd_dev_gone(struct domain_device *);
+
+void sas_smp_handler(struct bsg_job *job, struct Scsi_Host *shost,
+		struct sas_rphy *rphy);
+int sas_smp_phy_control(struct domain_device *dev, int phy_id,
+			enum phy_func phy_func, struct sas_phy_linkrates *);
+int sas_smp_get_phy_events(struct sas_phy *phy);
+
+int sas_notify_phy_event(struct asd_sas_phy *phy, enum phy_event event);
+int sas_notify_phy_event_gfp(struct asd_sas_phy *phy, enum phy_event event,
+			     gfp_t flags);
+void sas_device_set_phy(struct domain_device *dev, struct sas_port *port);
+struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy);
+struct domain_device *sas_ex_to_ata(struct domain_device *ex_dev, int phy_id);
+int sas_ex_phy_discover(struct domain_device *dev, int single);
+int sas_get_report_phy_sata(struct domain_device *dev, int phy_id,
+			    struct smp_resp *rps_resp);
+int sas_try_ata_reset(struct asd_sas_phy *phy);
+void sas_hae_reset(struct work_struct *work);
+
+void sas_free_device(struct kref *kref);
+void sas_destruct_devices(struct asd_sas_port *port);
+
+extern const work_func_t sas_phy_event_fns[PHY_NUM_EVENTS];
+extern const work_func_t sas_port_event_fns[PORT_NUM_EVENTS];
+
+#ifdef CONFIG_SCSI_SAS_HOST_SMP
+extern void sas_smp_host_handler(struct bsg_job *job, struct Scsi_Host *shost);
+#else
+static inline void sas_smp_host_handler(struct bsg_job *job,
+		struct Scsi_Host *shost)
+{
+	shost_printk(KERN_ERR, shost,
+		"Cannot send SMP to a sas host (not enabled in CONFIG)\n");
+	bsg_job_done(job, -EINVAL, 0);
+}
+#endif
+
+static inline void sas_fail_probe(struct domain_device *dev, const char *func, int err)
+{
+	pr_warn("%s: for %s device %016llx returned %d\n",
+		func, dev->parent ? "exp-attached" :
+		"direct-attached",
+		SAS_ADDR(dev->sas_addr), err);
+	sas_unregister_dev(dev->port, dev);
+}
+
+static inline void sas_fill_in_rphy(struct domain_device *dev,
+				    struct sas_rphy *rphy)
+{
+	rphy->identify.sas_address = SAS_ADDR(dev->sas_addr);
+	rphy->identify.initiator_port_protocols = dev->iproto;
+	rphy->identify.target_port_protocols = dev->tproto;
+	switch (dev->dev_type) {
+	case SAS_SATA_DEV:
+		/* FIXME: need sata device type */
+	case SAS_END_DEVICE:
+	case SAS_SATA_PENDING:
+		rphy->identify.device_type = SAS_END_DEVICE;
+		break;
+	case SAS_EDGE_EXPANDER_DEVICE:
+		rphy->identify.device_type = SAS_EDGE_EXPANDER_DEVICE;
+		break;
+	case SAS_FANOUT_EXPANDER_DEVICE:
+		rphy->identify.device_type = SAS_FANOUT_EXPANDER_DEVICE;
+		break;
+	default:
+		rphy->identify.device_type = SAS_PHY_UNUSED;
+		break;
+	}
+}
+
+static inline void sas_phy_set_target(struct asd_sas_phy *p, struct domain_device *dev)
+{
+	struct sas_phy *phy = p->phy;
+
+	if (dev) {
+		if (dev_is_sata(dev))
+			phy->identify.device_type = SAS_END_DEVICE;
+		else
+			phy->identify.device_type = dev->dev_type;
+		phy->identify.target_port_protocols = dev->tproto;
+	} else {
+		phy->identify.device_type = SAS_PHY_UNUSED;
+		phy->identify.target_port_protocols = 0;
+	}
+}
+
+static inline void sas_add_parent_port(struct domain_device *dev, int phy_id)
+{
+	struct expander_device *ex = &dev->ex_dev;
+	struct ex_phy *ex_phy = &ex->ex_phy[phy_id];
+
+	if (!ex->parent_port) {
+		ex->parent_port = sas_port_alloc(&dev->rphy->dev, phy_id);
+		/* FIXME: error handling */
+		BUG_ON(!ex->parent_port);
+		BUG_ON(sas_port_add(ex->parent_port));
+		sas_port_mark_backlink(ex->parent_port);
+	}
+	sas_port_add_phy(ex->parent_port, ex_phy->phy);
+}
+
+static inline struct domain_device *sas_alloc_device(void)
+{
+	struct domain_device *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+
+	if (dev) {
+		INIT_LIST_HEAD(&dev->siblings);
+		INIT_LIST_HEAD(&dev->dev_list_node);
+		INIT_LIST_HEAD(&dev->disco_list_node);
+		kref_init(&dev->kref);
+		spin_lock_init(&dev->done_lock);
+	}
+	return dev;
+}
+
+static inline void sas_put_device(struct domain_device *dev)
+{
+	kref_put(&dev->kref, sas_free_device);
+}
+
+#endif /* _SAS_INTERNAL_H_ */
diff --git a/drivers/scsi/libsas/sas_phy.c b/drivers/scsi/libsas/sas_phy.c
new file mode 100644
index 000000000..4ca4b1f30
--- /dev/null
+++ b/drivers/scsi/libsas/sas_phy.c
@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Serial Attached SCSI (SAS) Phy class
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+ */
+
+#include "sas_internal.h"
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_sas.h>
+#include "../scsi_sas_internal.h"
+
+/* ---------- Phy events ---------- */
+
+static void sas_phye_loss_of_signal(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+
+	phy->error = 0;
+	sas_deform_port(phy, 1);
+}
+
+static void sas_phye_oob_done(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+
+	phy->error = 0;
+}
+
+static void sas_phye_oob_error(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+	struct sas_ha_struct *sas_ha = phy->ha;
+	struct asd_sas_port *port = phy->port;
+	struct sas_internal *i =
+		to_sas_internal(sas_ha->core.shost->transportt);
+
+	sas_deform_port(phy, 1);
+
+	if (!port && phy->enabled && i->dft->lldd_control_phy) {
+		phy->error++;
+		switch (phy->error) {
+		case 1:
+		case 2:
+			i->dft->lldd_control_phy(phy, PHY_FUNC_HARD_RESET,
+						 NULL);
+			break;
+		case 3:
+		default:
+			phy->error = 0;
+			phy->enabled = 0;
+			i->dft->lldd_control_phy(phy, PHY_FUNC_DISABLE, NULL);
+			break;
+		}
+	}
+}
+
+static void sas_phye_spinup_hold(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+	struct sas_ha_struct *sas_ha = phy->ha;
+	struct sas_internal *i =
+		to_sas_internal(sas_ha->core.shost->transportt);
+
+	phy->error = 0;
+	i->dft->lldd_control_phy(phy, PHY_FUNC_RELEASE_SPINUP_HOLD, NULL);
+}
+
+static void sas_phye_resume_timeout(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+
+	/* phew, lldd got the phy back in the nick of time */
+	if (!phy->suspended) {
+		dev_info(&phy->phy->dev, "resume timeout cancelled\n");
+		return;
+	}
+
+	phy->error = 0;
+	phy->suspended = 0;
+	sas_deform_port(phy, 1);
+}
+
+
+static void sas_phye_shutdown(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+	struct sas_ha_struct *sas_ha = phy->ha;
+	struct sas_internal *i =
+		to_sas_internal(sas_ha->core.shost->transportt);
+
+	if (phy->enabled) {
+		int ret;
+
+		phy->error = 0;
+		phy->enabled = 0;
+		ret = i->dft->lldd_control_phy(phy, PHY_FUNC_DISABLE, NULL);
+		if (ret)
+			pr_notice("lldd disable phy%d returned %d\n", phy->id,
+				  ret);
+	} else
+		pr_notice("phy%d is not enabled, cannot shutdown\n", phy->id);
+	phy->in_shutdown = 0;
+}
+
+/* ---------- Phy class registration ---------- */
+
+int sas_register_phys(struct sas_ha_struct *sas_ha)
+{
+	int i;
+
+	/* Now register the phys. */
+	for (i = 0; i < sas_ha->num_phys; i++) {
+		struct asd_sas_phy *phy = sas_ha->sas_phy[i];
+
+		phy->error = 0;
+		atomic_set(&phy->event_nr, 0);
+		INIT_LIST_HEAD(&phy->port_phy_el);
+
+		phy->port = NULL;
+		phy->ha = sas_ha;
+		spin_lock_init(&phy->frame_rcvd_lock);
+		spin_lock_init(&phy->sas_prim_lock);
+		phy->frame_rcvd_size = 0;
+
+		phy->phy = sas_phy_alloc(&sas_ha->core.shost->shost_gendev, i);
+		if (!phy->phy)
+			return -ENOMEM;
+
+		phy->phy->identify.initiator_port_protocols =
+			phy->iproto;
+		phy->phy->identify.target_port_protocols = phy->tproto;
+		phy->phy->identify.sas_address = SAS_ADDR(sas_ha->sas_addr);
+		phy->phy->identify.phy_identifier = i;
+		phy->phy->minimum_linkrate_hw = SAS_LINK_RATE_UNKNOWN;
+		phy->phy->maximum_linkrate_hw = SAS_LINK_RATE_UNKNOWN;
+		phy->phy->minimum_linkrate = SAS_LINK_RATE_UNKNOWN;
+		phy->phy->maximum_linkrate = SAS_LINK_RATE_UNKNOWN;
+		phy->phy->negotiated_linkrate = SAS_LINK_RATE_UNKNOWN;
+
+		sas_phy_add(phy->phy);
+	}
+
+	return 0;
+}
+
+const work_func_t sas_phy_event_fns[PHY_NUM_EVENTS] = {
+	[PHYE_LOSS_OF_SIGNAL] = sas_phye_loss_of_signal,
+	[PHYE_OOB_DONE] = sas_phye_oob_done,
+	[PHYE_OOB_ERROR] = sas_phye_oob_error,
+	[PHYE_SPINUP_HOLD] = sas_phye_spinup_hold,
+	[PHYE_RESUME_TIMEOUT] = sas_phye_resume_timeout,
+	[PHYE_SHUTDOWN] = sas_phye_shutdown,
+};
diff --git a/drivers/scsi/libsas/sas_port.c b/drivers/scsi/libsas/sas_port.c
new file mode 100644
index 000000000..e3d03d744
--- /dev/null
+++ b/drivers/scsi/libsas/sas_port.c
@@ -0,0 +1,362 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Serial Attached SCSI (SAS) Port class
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+ */
+
+#include "sas_internal.h"
+
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_sas.h>
+#include "../scsi_sas_internal.h"
+
+static bool phy_is_wideport_member(struct asd_sas_port *port, struct asd_sas_phy *phy)
+{
+	struct sas_ha_struct *sas_ha = phy->ha;
+
+	if (memcmp(port->attached_sas_addr, phy->attached_sas_addr,
+		   SAS_ADDR_SIZE) != 0 || (sas_ha->strict_wide_ports &&
+	     memcmp(port->sas_addr, phy->sas_addr, SAS_ADDR_SIZE) != 0))
+		return false;
+	return true;
+}
+
+static void sas_resume_port(struct asd_sas_phy *phy)
+{
+	struct domain_device *dev, *n;
+	struct asd_sas_port *port = phy->port;
+	struct sas_ha_struct *sas_ha = phy->ha;
+	struct sas_internal *si = to_sas_internal(sas_ha->core.shost->transportt);
+
+	if (si->dft->lldd_port_formed)
+		si->dft->lldd_port_formed(phy);
+
+	if (port->suspended)
+		port->suspended = 0;
+	else {
+		/* we only need to handle "link returned" actions once */
+		return;
+	}
+
+	/* if the port came back:
+	 * 1/ presume every device came back
+	 * 2/ force the next revalidation to check all expander phys
+	 */
+	list_for_each_entry_safe(dev, n, &port->dev_list, dev_list_node) {
+		int i, rc;
+
+		rc = sas_notify_lldd_dev_found(dev);
+		if (rc) {
+			sas_unregister_dev(port, dev);
+			sas_destruct_devices(port);
+			continue;
+		}
+
+		if (dev_is_expander(dev->dev_type)) {
+			dev->ex_dev.ex_change_count = -1;
+			for (i = 0; i < dev->ex_dev.num_phys; i++) {
+				struct ex_phy *phy = &dev->ex_dev.ex_phy[i];
+
+				phy->phy_change_count = -1;
+			}
+		}
+	}
+
+	sas_discover_event(port, DISCE_RESUME);
+}
+
+/**
+ * sas_form_port - add this phy to a port
+ * @phy: the phy of interest
+ *
+ * This function adds this phy to an existing port, thus creating a wide
+ * port, or it creates a port and adds the phy to the port.
+ */
+static void sas_form_port(struct asd_sas_phy *phy)
+{
+	int i;
+	struct sas_ha_struct *sas_ha = phy->ha;
+	struct asd_sas_port *port = phy->port;
+	struct domain_device *port_dev;
+	struct sas_internal *si =
+		to_sas_internal(sas_ha->core.shost->transportt);
+	unsigned long flags;
+
+	if (port) {
+		if (!phy_is_wideport_member(port, phy))
+			sas_deform_port(phy, 0);
+		else if (phy->suspended) {
+			phy->suspended = 0;
+			sas_resume_port(phy);
+
+			/* phy came back, try to cancel the timeout */
+			wake_up(&sas_ha->eh_wait_q);
+			return;
+		} else {
+			pr_info("%s: phy%d belongs to port%d already(%d)!\n",
+				__func__, phy->id, phy->port->id,
+				phy->port->num_phys);
+			return;
+		}
+	}
+
+	/* see if the phy should be part of a wide port */
+	spin_lock_irqsave(&sas_ha->phy_port_lock, flags);
+	for (i = 0; i < sas_ha->num_phys; i++) {
+		port = sas_ha->sas_port[i];
+		spin_lock(&port->phy_list_lock);
+		if (*(u64 *) port->sas_addr &&
+		    phy_is_wideport_member(port, phy) && port->num_phys > 0) {
+			/* wide port */
+			pr_debug("phy%d matched wide port%d\n", phy->id,
+				 port->id);
+			break;
+		}
+		spin_unlock(&port->phy_list_lock);
+	}
+	/* The phy does not match any existing port, create a new one */
+	if (i == sas_ha->num_phys) {
+		for (i = 0; i < sas_ha->num_phys; i++) {
+			port = sas_ha->sas_port[i];
+			spin_lock(&port->phy_list_lock);
+			if (*(u64 *)port->sas_addr == 0
+				&& port->num_phys == 0) {
+				memcpy(port->sas_addr, phy->sas_addr,
+					SAS_ADDR_SIZE);
+				break;
+			}
+			spin_unlock(&port->phy_list_lock);
+		}
+	}
+
+	if (i >= sas_ha->num_phys) {
+		pr_err("%s: couldn't find a free port, bug?\n", __func__);
+		spin_unlock_irqrestore(&sas_ha->phy_port_lock, flags);
+		return;
+	}
+
+	/* add the phy to the port */
+	port_dev = port->port_dev;
+	list_add_tail(&phy->port_phy_el, &port->phy_list);
+	sas_phy_set_target(phy, port_dev);
+	phy->port = port;
+	port->num_phys++;
+	port->phy_mask |= (1U << phy->id);
+
+	if (*(u64 *)port->attached_sas_addr == 0) {
+		port->class = phy->class;
+		memcpy(port->attached_sas_addr, phy->attached_sas_addr,
+		       SAS_ADDR_SIZE);
+		port->iproto = phy->iproto;
+		port->tproto = phy->tproto;
+		port->oob_mode = phy->oob_mode;
+		port->linkrate = phy->linkrate;
+	} else
+		port->linkrate = max(port->linkrate, phy->linkrate);
+	spin_unlock(&port->phy_list_lock);
+	spin_unlock_irqrestore(&sas_ha->phy_port_lock, flags);
+
+	if (!port->port) {
+		port->port = sas_port_alloc(phy->phy->dev.parent, port->id);
+		BUG_ON(!port->port);
+		sas_port_add(port->port);
+	}
+	sas_port_add_phy(port->port, phy->phy);
+
+	pr_debug("%s added to %s, phy_mask:0x%x (%016llx)\n",
+		 dev_name(&phy->phy->dev), dev_name(&port->port->dev),
+		 port->phy_mask,
+		 SAS_ADDR(port->attached_sas_addr));
+
+	if (port_dev)
+		port_dev->pathways = port->num_phys;
+
+	/* Tell the LLDD about this port formation. */
+	if (si->dft->lldd_port_formed)
+		si->dft->lldd_port_formed(phy);
+
+	sas_discover_event(phy->port, DISCE_DISCOVER_DOMAIN);
+	/* Only insert a revalidate event after initial discovery */
+	if (port_dev && dev_is_expander(port_dev->dev_type)) {
+		struct expander_device *ex_dev = &port_dev->ex_dev;
+
+		ex_dev->ex_change_count = -1;
+		sas_discover_event(port, DISCE_REVALIDATE_DOMAIN);
+	}
+	flush_workqueue(sas_ha->disco_q);
+}
+
+/**
+ * sas_deform_port - remove this phy from the port it belongs to
+ * @phy: the phy of interest
+ * @gone: whether or not the PHY is gone
+ *
+ * This is called when the physical link to the other phy has been
+ * lost (on this phy), in Event thread context. We cannot delay here.
+ */
+void sas_deform_port(struct asd_sas_phy *phy, int gone)
+{
+	struct sas_ha_struct *sas_ha = phy->ha;
+	struct asd_sas_port *port = phy->port;
+	struct sas_internal *si =
+		to_sas_internal(sas_ha->core.shost->transportt);
+	struct domain_device *dev;
+	unsigned long flags;
+
+	if (!port)
+		return;		  /* done by a phy event */
+
+	dev = port->port_dev;
+	if (dev)
+		dev->pathways--;
+
+	if (port->num_phys == 1) {
+		sas_unregister_domain_devices(port, gone);
+		sas_destruct_devices(port);
+		sas_port_delete(port->port);
+		port->port = NULL;
+	} else {
+		sas_port_delete_phy(port->port, phy->phy);
+		sas_device_set_phy(dev, port->port);
+	}
+
+	if (si->dft->lldd_port_deformed)
+		si->dft->lldd_port_deformed(phy);
+
+	spin_lock_irqsave(&sas_ha->phy_port_lock, flags);
+	spin_lock(&port->phy_list_lock);
+
+	list_del_init(&phy->port_phy_el);
+	sas_phy_set_target(phy, NULL);
+	phy->port = NULL;
+	port->num_phys--;
+	port->phy_mask &= ~(1U << phy->id);
+
+	if (port->num_phys == 0) {
+		INIT_LIST_HEAD(&port->phy_list);
+		memset(port->sas_addr, 0, SAS_ADDR_SIZE);
+		memset(port->attached_sas_addr, 0, SAS_ADDR_SIZE);
+		port->class = 0;
+		port->iproto = 0;
+		port->tproto = 0;
+		port->oob_mode = 0;
+		port->phy_mask = 0;
+	}
+	spin_unlock(&port->phy_list_lock);
+	spin_unlock_irqrestore(&sas_ha->phy_port_lock, flags);
+
+	/* Only insert revalidate event if the port still has members */
+	if (port->port && dev && dev_is_expander(dev->dev_type)) {
+		struct expander_device *ex_dev = &dev->ex_dev;
+
+		ex_dev->ex_change_count = -1;
+		sas_discover_event(port, DISCE_REVALIDATE_DOMAIN);
+	}
+	flush_workqueue(sas_ha->disco_q);
+
+	return;
+}
+
+/* ---------- SAS port events ---------- */
+
+void sas_porte_bytes_dmaed(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+
+	sas_form_port(phy);
+}
+
+void sas_porte_broadcast_rcvd(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+	unsigned long flags;
+	u32 prim;
+
+	spin_lock_irqsave(&phy->sas_prim_lock, flags);
+	prim = phy->sas_prim;
+	spin_unlock_irqrestore(&phy->sas_prim_lock, flags);
+
+	pr_debug("broadcast received: %d\n", prim);
+	sas_discover_event(phy->port, DISCE_REVALIDATE_DOMAIN);
+
+	if (phy->port)
+		flush_workqueue(phy->port->ha->disco_q);
+}
+
+void sas_porte_link_reset_err(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+
+	sas_deform_port(phy, 1);
+}
+
+void sas_porte_timer_event(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+
+	sas_deform_port(phy, 1);
+}
+
+void sas_porte_hard_reset(struct work_struct *work)
+{
+	struct asd_sas_event *ev = to_asd_sas_event(work);
+	struct asd_sas_phy *phy = ev->phy;
+
+	sas_deform_port(phy, 1);
+}
+
+/* ---------- SAS port registration ---------- */
+
+static void sas_init_port(struct asd_sas_port *port,
+			  struct sas_ha_struct *sas_ha, int i)
+{
+	memset(port, 0, sizeof(*port));
+	port->id = i;
+	INIT_LIST_HEAD(&port->dev_list);
+	INIT_LIST_HEAD(&port->disco_list);
+	INIT_LIST_HEAD(&port->destroy_list);
+	INIT_LIST_HEAD(&port->sas_port_del_list);
+	spin_lock_init(&port->phy_list_lock);
+	INIT_LIST_HEAD(&port->phy_list);
+	port->ha = sas_ha;
+
+	spin_lock_init(&port->dev_list_lock);
+}
+
+int sas_register_ports(struct sas_ha_struct *sas_ha)
+{
+	int i;
+
+	/* initialize the ports and discovery */
+	for (i = 0; i < sas_ha->num_phys; i++) {
+		struct asd_sas_port *port = sas_ha->sas_port[i];
+
+		sas_init_port(port, sas_ha, i);
+		sas_init_disc(&port->disc, port);
+	}
+	return 0;
+}
+
+void sas_unregister_ports(struct sas_ha_struct *sas_ha)
+{
+	int i;
+
+	for (i = 0; i < sas_ha->num_phys; i++)
+		if (sas_ha->sas_phy[i]->port)
+			sas_deform_port(sas_ha->sas_phy[i], 0);
+
+}
+
+const work_func_t sas_port_event_fns[PORT_NUM_EVENTS] = {
+	[PORTE_BYTES_DMAED] = sas_porte_bytes_dmaed,
+	[PORTE_BROADCAST_RCVD] = sas_porte_broadcast_rcvd,
+	[PORTE_LINK_RESET_ERR] = sas_porte_link_reset_err,
+	[PORTE_TIMER_EVENT] = sas_porte_timer_event,
+	[PORTE_HARD_RESET] = sas_porte_hard_reset,
+};
diff --git a/drivers/scsi/libsas/sas_scsi_host.c b/drivers/scsi/libsas/sas_scsi_host.c
new file mode 100644
index 000000000..ee44a0d77
--- /dev/null
+++ b/drivers/scsi/libsas/sas_scsi_host.c
@@ -0,0 +1,970 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Serial Attached SCSI (SAS) class SCSI Host glue.
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+ */
+
+#include <linux/kthread.h>
+#include <linux/firmware.h>
+#include <linux/export.h>
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+
+#include "sas_internal.h"
+
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_transport_sas.h>
+#include <scsi/sas_ata.h>
+#include "../scsi_sas_internal.h"
+#include "../scsi_transport_api.h"
+#include "../scsi_priv.h"
+
+#include <linux/err.h>
+#include <linux/blkdev.h>
+#include <linux/freezer.h>
+#include <linux/gfp.h>
+#include <linux/scatterlist.h>
+#include <linux/libata.h>
+
+/* record final status and free the task */
+static void sas_end_task(struct scsi_cmnd *sc, struct sas_task *task)
+{
+	struct task_status_struct *ts = &task->task_status;
+	int hs = 0, stat = 0;
+
+	if (ts->resp == SAS_TASK_UNDELIVERED) {
+		/* transport error */
+		hs = DID_NO_CONNECT;
+	} else { /* ts->resp == SAS_TASK_COMPLETE */
+		/* task delivered, what happened afterwards? */
+		switch (ts->stat) {
+		case SAS_DEV_NO_RESPONSE:
+		case SAS_INTERRUPTED:
+		case SAS_PHY_DOWN:
+		case SAS_NAK_R_ERR:
+		case SAS_OPEN_TO:
+			hs = DID_NO_CONNECT;
+			break;
+		case SAS_DATA_UNDERRUN:
+			scsi_set_resid(sc, ts->residual);
+			if (scsi_bufflen(sc) - scsi_get_resid(sc) < sc->underflow)
+				hs = DID_ERROR;
+			break;
+		case SAS_DATA_OVERRUN:
+			hs = DID_ERROR;
+			break;
+		case SAS_QUEUE_FULL:
+			hs = DID_SOFT_ERROR; /* retry */
+			break;
+		case SAS_DEVICE_UNKNOWN:
+			hs = DID_BAD_TARGET;
+			break;
+		case SAS_SG_ERR:
+			hs = DID_PARITY;
+			break;
+		case SAS_OPEN_REJECT:
+			if (ts->open_rej_reason == SAS_OREJ_RSVD_RETRY)
+				hs = DID_SOFT_ERROR; /* retry */
+			else
+				hs = DID_ERROR;
+			break;
+		case SAS_PROTO_RESPONSE:
+			pr_notice("LLDD:%s sent SAS_PROTO_RESP for an SSP task; please report this\n",
+				  task->dev->port->ha->sas_ha_name);
+			break;
+		case SAS_ABORTED_TASK:
+			hs = DID_ABORT;
+			break;
+		case SAM_STAT_CHECK_CONDITION:
+			memcpy(sc->sense_buffer, ts->buf,
+			       min(SCSI_SENSE_BUFFERSIZE, ts->buf_valid_size));
+			stat = SAM_STAT_CHECK_CONDITION;
+			break;
+		default:
+			stat = ts->stat;
+			break;
+		}
+	}
+
+	sc->result = (hs << 16) | stat;
+	ASSIGN_SAS_TASK(sc, NULL);
+	sas_free_task(task);
+}
+
+static void sas_scsi_task_done(struct sas_task *task)
+{
+	struct scsi_cmnd *sc = task->uldd_task;
+	struct domain_device *dev = task->dev;
+	struct sas_ha_struct *ha = dev->port->ha;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev->done_lock, flags);
+	if (test_bit(SAS_HA_FROZEN, &ha->state))
+		task = NULL;
+	else
+		ASSIGN_SAS_TASK(sc, NULL);
+	spin_unlock_irqrestore(&dev->done_lock, flags);
+
+	if (unlikely(!task)) {
+		/* task will be completed by the error handler */
+		pr_debug("task done but aborted\n");
+		return;
+	}
+
+	if (unlikely(!sc)) {
+		pr_debug("task_done called with non existing SCSI cmnd!\n");
+		sas_free_task(task);
+		return;
+	}
+
+	sas_end_task(sc, task);
+	sc->scsi_done(sc);
+}
+
+static struct sas_task *sas_create_task(struct scsi_cmnd *cmd,
+					       struct domain_device *dev,
+					       gfp_t gfp_flags)
+{
+	struct sas_task *task = sas_alloc_task(gfp_flags);
+	struct scsi_lun lun;
+
+	if (!task)
+		return NULL;
+
+	task->uldd_task = cmd;
+	ASSIGN_SAS_TASK(cmd, task);
+
+	task->dev = dev;
+	task->task_proto = task->dev->tproto; /* BUG_ON(!SSP) */
+
+	task->ssp_task.retry_count = 1;
+	int_to_scsilun(cmd->device->lun, &lun);
+	memcpy(task->ssp_task.LUN, &lun.scsi_lun, 8);
+	task->ssp_task.task_attr = TASK_ATTR_SIMPLE;
+	task->ssp_task.cmd = cmd;
+
+	task->scatter = scsi_sglist(cmd);
+	task->num_scatter = scsi_sg_count(cmd);
+	task->total_xfer_len = scsi_bufflen(cmd);
+	task->data_dir = cmd->sc_data_direction;
+
+	task->task_done = sas_scsi_task_done;
+
+	return task;
+}
+
+int sas_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd)
+{
+	struct sas_internal *i = to_sas_internal(host->transportt);
+	struct domain_device *dev = cmd_to_domain_dev(cmd);
+	struct sas_task *task;
+	int res = 0;
+
+	/* If the device fell off, no sense in issuing commands */
+	if (test_bit(SAS_DEV_GONE, &dev->state)) {
+		cmd->result = DID_BAD_TARGET << 16;
+		goto out_done;
+	}
+
+	if (dev_is_sata(dev)) {
+		spin_lock_irq(dev->sata_dev.ap->lock);
+		res = ata_sas_queuecmd(cmd, dev->sata_dev.ap);
+		spin_unlock_irq(dev->sata_dev.ap->lock);
+		return res;
+	}
+
+	task = sas_create_task(cmd, dev, GFP_ATOMIC);
+	if (!task)
+		return SCSI_MLQUEUE_HOST_BUSY;
+
+	res = i->dft->lldd_execute_task(task, GFP_ATOMIC);
+	if (res)
+		goto out_free_task;
+	return 0;
+
+out_free_task:
+	pr_debug("lldd_execute_task returned: %d\n", res);
+	ASSIGN_SAS_TASK(cmd, NULL);
+	sas_free_task(task);
+	if (res == -SAS_QUEUE_FULL)
+		cmd->result = DID_SOFT_ERROR << 16; /* retry */
+	else
+		cmd->result = DID_ERROR << 16;
+out_done:
+	cmd->scsi_done(cmd);
+	return 0;
+}
+
+static void sas_eh_finish_cmd(struct scsi_cmnd *cmd)
+{
+	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(cmd->device->host);
+	struct domain_device *dev = cmd_to_domain_dev(cmd);
+	struct sas_task *task = TO_SAS_TASK(cmd);
+
+	/* At this point, we only get called following an actual abort
+	 * of the task, so we should be guaranteed not to be racing with
+	 * any completions from the LLD.  Task is freed after this.
+	 */
+	sas_end_task(cmd, task);
+
+	if (dev_is_sata(dev)) {
+		/* defer commands to libata so that libata EH can
+		 * handle ata qcs correctly
+		 */
+		list_move_tail(&cmd->eh_entry, &sas_ha->eh_ata_q);
+		return;
+	}
+
+	/* now finish the command and move it on to the error
+	 * handler done list, this also takes it off the
+	 * error handler pending list.
+	 */
+	scsi_eh_finish_cmd(cmd, &sas_ha->eh_done_q);
+}
+
+static void sas_scsi_clear_queue_lu(struct list_head *error_q, struct scsi_cmnd *my_cmd)
+{
+	struct scsi_cmnd *cmd, *n;
+
+	list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
+		if (cmd->device->sdev_target == my_cmd->device->sdev_target &&
+		    cmd->device->lun == my_cmd->device->lun)
+			sas_eh_finish_cmd(cmd);
+	}
+}
+
+static void sas_scsi_clear_queue_I_T(struct list_head *error_q,
+				     struct domain_device *dev)
+{
+	struct scsi_cmnd *cmd, *n;
+
+	list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
+		struct domain_device *x = cmd_to_domain_dev(cmd);
+
+		if (x == dev)
+			sas_eh_finish_cmd(cmd);
+	}
+}
+
+static void sas_scsi_clear_queue_port(struct list_head *error_q,
+				      struct asd_sas_port *port)
+{
+	struct scsi_cmnd *cmd, *n;
+
+	list_for_each_entry_safe(cmd, n, error_q, eh_entry) {
+		struct domain_device *dev = cmd_to_domain_dev(cmd);
+		struct asd_sas_port *x = dev->port;
+
+		if (x == port)
+			sas_eh_finish_cmd(cmd);
+	}
+}
+
+enum task_disposition {
+	TASK_IS_DONE,
+	TASK_IS_ABORTED,
+	TASK_IS_AT_LU,
+	TASK_IS_NOT_AT_LU,
+	TASK_ABORT_FAILED,
+};
+
+static enum task_disposition sas_scsi_find_task(struct sas_task *task)
+{
+	unsigned long flags;
+	int i, res;
+	struct sas_internal *si =
+		to_sas_internal(task->dev->port->ha->core.shost->transportt);
+
+	for (i = 0; i < 5; i++) {
+		pr_notice("%s: aborting task 0x%p\n", __func__, task);
+		res = si->dft->lldd_abort_task(task);
+
+		spin_lock_irqsave(&task->task_state_lock, flags);
+		if (task->task_state_flags & SAS_TASK_STATE_DONE) {
+			spin_unlock_irqrestore(&task->task_state_lock, flags);
+			pr_debug("%s: task 0x%p is done\n", __func__, task);
+			return TASK_IS_DONE;
+		}
+		spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+		if (res == TMF_RESP_FUNC_COMPLETE) {
+			pr_notice("%s: task 0x%p is aborted\n",
+				  __func__, task);
+			return TASK_IS_ABORTED;
+		} else if (si->dft->lldd_query_task) {
+			pr_notice("%s: querying task 0x%p\n", __func__, task);
+			res = si->dft->lldd_query_task(task);
+			switch (res) {
+			case TMF_RESP_FUNC_SUCC:
+				pr_notice("%s: task 0x%p at LU\n", __func__,
+					  task);
+				return TASK_IS_AT_LU;
+			case TMF_RESP_FUNC_COMPLETE:
+				pr_notice("%s: task 0x%p not at LU\n",
+					  __func__, task);
+				return TASK_IS_NOT_AT_LU;
+			case TMF_RESP_FUNC_FAILED:
+				pr_notice("%s: task 0x%p failed to abort\n",
+					  __func__, task);
+				return TASK_ABORT_FAILED;
+			}
+
+		}
+	}
+	return res;
+}
+
+static int sas_recover_lu(struct domain_device *dev, struct scsi_cmnd *cmd)
+{
+	int res = TMF_RESP_FUNC_FAILED;
+	struct scsi_lun lun;
+	struct sas_internal *i =
+		to_sas_internal(dev->port->ha->core.shost->transportt);
+
+	int_to_scsilun(cmd->device->lun, &lun);
+
+	pr_notice("eh: device %016llx LUN 0x%llx has the task\n",
+		  SAS_ADDR(dev->sas_addr),
+		  cmd->device->lun);
+
+	if (i->dft->lldd_abort_task_set)
+		res = i->dft->lldd_abort_task_set(dev, lun.scsi_lun);
+
+	if (res == TMF_RESP_FUNC_FAILED) {
+		if (i->dft->lldd_clear_task_set)
+			res = i->dft->lldd_clear_task_set(dev, lun.scsi_lun);
+	}
+
+	if (res == TMF_RESP_FUNC_FAILED) {
+		if (i->dft->lldd_lu_reset)
+			res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
+	}
+
+	return res;
+}
+
+static int sas_recover_I_T(struct domain_device *dev)
+{
+	int res = TMF_RESP_FUNC_FAILED;
+	struct sas_internal *i =
+		to_sas_internal(dev->port->ha->core.shost->transportt);
+
+	pr_notice("I_T nexus reset for dev %016llx\n",
+		  SAS_ADDR(dev->sas_addr));
+
+	if (i->dft->lldd_I_T_nexus_reset)
+		res = i->dft->lldd_I_T_nexus_reset(dev);
+
+	return res;
+}
+
+/* take a reference on the last known good phy for this device */
+struct sas_phy *sas_get_local_phy(struct domain_device *dev)
+{
+	struct sas_ha_struct *ha = dev->port->ha;
+	struct sas_phy *phy;
+	unsigned long flags;
+
+	/* a published domain device always has a valid phy, it may be
+	 * stale, but it is never NULL
+	 */
+	BUG_ON(!dev->phy);
+
+	spin_lock_irqsave(&ha->phy_port_lock, flags);
+	phy = dev->phy;
+	get_device(&phy->dev);
+	spin_unlock_irqrestore(&ha->phy_port_lock, flags);
+
+	return phy;
+}
+EXPORT_SYMBOL_GPL(sas_get_local_phy);
+
+static void sas_wait_eh(struct domain_device *dev)
+{
+	struct sas_ha_struct *ha = dev->port->ha;
+	DEFINE_WAIT(wait);
+
+	if (dev_is_sata(dev)) {
+		ata_port_wait_eh(dev->sata_dev.ap);
+		return;
+	}
+ retry:
+	spin_lock_irq(&ha->lock);
+
+	while (test_bit(SAS_DEV_EH_PENDING, &dev->state)) {
+		prepare_to_wait(&ha->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
+		spin_unlock_irq(&ha->lock);
+		schedule();
+		spin_lock_irq(&ha->lock);
+	}
+	finish_wait(&ha->eh_wait_q, &wait);
+
+	spin_unlock_irq(&ha->lock);
+
+	/* make sure SCSI EH is complete */
+	if (scsi_host_in_recovery(ha->core.shost)) {
+		msleep(10);
+		goto retry;
+	}
+}
+
+static int sas_queue_reset(struct domain_device *dev, int reset_type,
+			   u64 lun, int wait)
+{
+	struct sas_ha_struct *ha = dev->port->ha;
+	int scheduled = 0, tries = 100;
+
+	/* ata: promote lun reset to bus reset */
+	if (dev_is_sata(dev)) {
+		sas_ata_schedule_reset(dev);
+		if (wait)
+			sas_ata_wait_eh(dev);
+		return SUCCESS;
+	}
+
+	while (!scheduled && tries--) {
+		spin_lock_irq(&ha->lock);
+		if (!test_bit(SAS_DEV_EH_PENDING, &dev->state) &&
+		    !test_bit(reset_type, &dev->state)) {
+			scheduled = 1;
+			ha->eh_active++;
+			list_add_tail(&dev->ssp_dev.eh_list_node, &ha->eh_dev_q);
+			set_bit(SAS_DEV_EH_PENDING, &dev->state);
+			set_bit(reset_type, &dev->state);
+			int_to_scsilun(lun, &dev->ssp_dev.reset_lun);
+			scsi_schedule_eh(ha->core.shost);
+		}
+		spin_unlock_irq(&ha->lock);
+
+		if (wait)
+			sas_wait_eh(dev);
+
+		if (scheduled)
+			return SUCCESS;
+	}
+
+	pr_warn("%s reset of %s failed\n",
+		reset_type == SAS_DEV_LU_RESET ? "LUN" : "Bus",
+		dev_name(&dev->rphy->dev));
+
+	return FAILED;
+}
+
+int sas_eh_abort_handler(struct scsi_cmnd *cmd)
+{
+	int res = TMF_RESP_FUNC_FAILED;
+	struct sas_task *task = TO_SAS_TASK(cmd);
+	struct Scsi_Host *host = cmd->device->host;
+	struct domain_device *dev = cmd_to_domain_dev(cmd);
+	struct sas_internal *i = to_sas_internal(host->transportt);
+	unsigned long flags;
+
+	if (!i->dft->lldd_abort_task)
+		return FAILED;
+
+	spin_lock_irqsave(host->host_lock, flags);
+	/* We cannot do async aborts for SATA devices */
+	if (dev_is_sata(dev) && !host->host_eh_scheduled) {
+		spin_unlock_irqrestore(host->host_lock, flags);
+		return FAILED;
+	}
+	spin_unlock_irqrestore(host->host_lock, flags);
+
+	if (task)
+		res = i->dft->lldd_abort_task(task);
+	else
+		pr_notice("no task to abort\n");
+	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
+		return SUCCESS;
+
+	return FAILED;
+}
+EXPORT_SYMBOL_GPL(sas_eh_abort_handler);
+
+/* Attempt to send a LUN reset message to a device */
+int sas_eh_device_reset_handler(struct scsi_cmnd *cmd)
+{
+	int res;
+	struct scsi_lun lun;
+	struct Scsi_Host *host = cmd->device->host;
+	struct domain_device *dev = cmd_to_domain_dev(cmd);
+	struct sas_internal *i = to_sas_internal(host->transportt);
+
+	if (current != host->ehandler)
+		return sas_queue_reset(dev, SAS_DEV_LU_RESET, cmd->device->lun, 0);
+
+	int_to_scsilun(cmd->device->lun, &lun);
+
+	if (!i->dft->lldd_lu_reset)
+		return FAILED;
+
+	res = i->dft->lldd_lu_reset(dev, lun.scsi_lun);
+	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE)
+		return SUCCESS;
+
+	return FAILED;
+}
+
+int sas_eh_target_reset_handler(struct scsi_cmnd *cmd)
+{
+	int res;
+	struct Scsi_Host *host = cmd->device->host;
+	struct domain_device *dev = cmd_to_domain_dev(cmd);
+	struct sas_internal *i = to_sas_internal(host->transportt);
+
+	if (current != host->ehandler)
+		return sas_queue_reset(dev, SAS_DEV_RESET, 0, 0);
+
+	if (!i->dft->lldd_I_T_nexus_reset)
+		return FAILED;
+
+	res = i->dft->lldd_I_T_nexus_reset(dev);
+	if (res == TMF_RESP_FUNC_SUCC || res == TMF_RESP_FUNC_COMPLETE ||
+	    res == -ENODEV)
+		return SUCCESS;
+
+	return FAILED;
+}
+
+/* Try to reset a device */
+static int try_to_reset_cmd_device(struct scsi_cmnd *cmd)
+{
+	int res;
+	struct Scsi_Host *shost = cmd->device->host;
+
+	if (!shost->hostt->eh_device_reset_handler)
+		goto try_target_reset;
+
+	res = shost->hostt->eh_device_reset_handler(cmd);
+	if (res == SUCCESS)
+		return res;
+
+try_target_reset:
+	if (shost->hostt->eh_target_reset_handler)
+		return shost->hostt->eh_target_reset_handler(cmd);
+
+	return FAILED;
+}
+
+static void sas_eh_handle_sas_errors(struct Scsi_Host *shost, struct list_head *work_q)
+{
+	struct scsi_cmnd *cmd, *n;
+	enum task_disposition res = TASK_IS_DONE;
+	int tmf_resp, need_reset;
+	struct sas_internal *i = to_sas_internal(shost->transportt);
+	unsigned long flags;
+	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	LIST_HEAD(done);
+
+	/* clean out any commands that won the completion vs eh race */
+	list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
+		struct domain_device *dev = cmd_to_domain_dev(cmd);
+		struct sas_task *task;
+
+		spin_lock_irqsave(&dev->done_lock, flags);
+		/* by this point the lldd has either observed
+		 * SAS_HA_FROZEN and is leaving the task alone, or has
+		 * won the race with eh and decided to complete it
+		 */
+		task = TO_SAS_TASK(cmd);
+		spin_unlock_irqrestore(&dev->done_lock, flags);
+
+		if (!task)
+			list_move_tail(&cmd->eh_entry, &done);
+	}
+
+ Again:
+	list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
+		struct sas_task *task = TO_SAS_TASK(cmd);
+
+		list_del_init(&cmd->eh_entry);
+
+		spin_lock_irqsave(&task->task_state_lock, flags);
+		need_reset = task->task_state_flags & SAS_TASK_NEED_DEV_RESET;
+		spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+		if (need_reset) {
+			pr_notice("%s: task 0x%p requests reset\n",
+				  __func__, task);
+			goto reset;
+		}
+
+		pr_debug("trying to find task 0x%p\n", task);
+		res = sas_scsi_find_task(task);
+
+		switch (res) {
+		case TASK_IS_DONE:
+			pr_notice("%s: task 0x%p is done\n", __func__,
+				    task);
+			sas_eh_finish_cmd(cmd);
+			continue;
+		case TASK_IS_ABORTED:
+			pr_notice("%s: task 0x%p is aborted\n",
+				  __func__, task);
+			sas_eh_finish_cmd(cmd);
+			continue;
+		case TASK_IS_AT_LU:
+			pr_info("task 0x%p is at LU: lu recover\n", task);
+ reset:
+			tmf_resp = sas_recover_lu(task->dev, cmd);
+			if (tmf_resp == TMF_RESP_FUNC_COMPLETE) {
+				pr_notice("dev %016llx LU 0x%llx is recovered\n",
+					  SAS_ADDR(task->dev),
+					  cmd->device->lun);
+				sas_eh_finish_cmd(cmd);
+				sas_scsi_clear_queue_lu(work_q, cmd);
+				goto Again;
+			}
+			fallthrough;
+		case TASK_IS_NOT_AT_LU:
+		case TASK_ABORT_FAILED:
+			pr_notice("task 0x%p is not at LU: I_T recover\n",
+				  task);
+			tmf_resp = sas_recover_I_T(task->dev);
+			if (tmf_resp == TMF_RESP_FUNC_COMPLETE ||
+			    tmf_resp == -ENODEV) {
+				struct domain_device *dev = task->dev;
+				pr_notice("I_T %016llx recovered\n",
+					  SAS_ADDR(task->dev->sas_addr));
+				sas_eh_finish_cmd(cmd);
+				sas_scsi_clear_queue_I_T(work_q, dev);
+				goto Again;
+			}
+			/* Hammer time :-) */
+			try_to_reset_cmd_device(cmd);
+			if (i->dft->lldd_clear_nexus_port) {
+				struct asd_sas_port *port = task->dev->port;
+				pr_debug("clearing nexus for port:%d\n",
+					  port->id);
+				res = i->dft->lldd_clear_nexus_port(port);
+				if (res == TMF_RESP_FUNC_COMPLETE) {
+					pr_notice("clear nexus port:%d succeeded\n",
+						  port->id);
+					sas_eh_finish_cmd(cmd);
+					sas_scsi_clear_queue_port(work_q,
+								  port);
+					goto Again;
+				}
+			}
+			if (i->dft->lldd_clear_nexus_ha) {
+				pr_debug("clear nexus ha\n");
+				res = i->dft->lldd_clear_nexus_ha(ha);
+				if (res == TMF_RESP_FUNC_COMPLETE) {
+					pr_notice("clear nexus ha succeeded\n");
+					sas_eh_finish_cmd(cmd);
+					goto clear_q;
+				}
+			}
+			/* If we are here -- this means that no amount
+			 * of effort could recover from errors.  Quite
+			 * possibly the HA just disappeared.
+			 */
+			pr_err("error from device %016llx, LUN 0x%llx couldn't be recovered in any way\n",
+			       SAS_ADDR(task->dev->sas_addr),
+			       cmd->device->lun);
+
+			sas_eh_finish_cmd(cmd);
+			goto clear_q;
+		}
+	}
+ out:
+	list_splice_tail(&done, work_q);
+	list_splice_tail_init(&ha->eh_ata_q, work_q);
+	return;
+
+ clear_q:
+	pr_debug("--- Exit %s -- clear_q\n", __func__);
+	list_for_each_entry_safe(cmd, n, work_q, eh_entry)
+		sas_eh_finish_cmd(cmd);
+	goto out;
+}
+
+static void sas_eh_handle_resets(struct Scsi_Host *shost)
+{
+	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	struct sas_internal *i = to_sas_internal(shost->transportt);
+
+	/* handle directed resets to sas devices */
+	spin_lock_irq(&ha->lock);
+	while (!list_empty(&ha->eh_dev_q)) {
+		struct domain_device *dev;
+		struct ssp_device *ssp;
+
+		ssp = list_entry(ha->eh_dev_q.next, typeof(*ssp), eh_list_node);
+		list_del_init(&ssp->eh_list_node);
+		dev = container_of(ssp, typeof(*dev), ssp_dev);
+		kref_get(&dev->kref);
+		WARN_ONCE(dev_is_sata(dev), "ssp reset to ata device?\n");
+
+		spin_unlock_irq(&ha->lock);
+
+		if (test_and_clear_bit(SAS_DEV_LU_RESET, &dev->state))
+			i->dft->lldd_lu_reset(dev, ssp->reset_lun.scsi_lun);
+
+		if (test_and_clear_bit(SAS_DEV_RESET, &dev->state))
+			i->dft->lldd_I_T_nexus_reset(dev);
+
+		sas_put_device(dev);
+		spin_lock_irq(&ha->lock);
+		clear_bit(SAS_DEV_EH_PENDING, &dev->state);
+		ha->eh_active--;
+	}
+	spin_unlock_irq(&ha->lock);
+}
+
+
+void sas_scsi_recover_host(struct Scsi_Host *shost)
+{
+	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	LIST_HEAD(eh_work_q);
+	int tries = 0;
+	bool retry;
+
+retry:
+	tries++;
+	retry = true;
+	spin_lock_irq(shost->host_lock);
+	list_splice_init(&shost->eh_cmd_q, &eh_work_q);
+	spin_unlock_irq(shost->host_lock);
+
+	pr_notice("Enter %s busy: %d failed: %d\n",
+		  __func__, scsi_host_busy(shost), shost->host_failed);
+	/*
+	 * Deal with commands that still have SAS tasks (i.e. they didn't
+	 * complete via the normal sas_task completion mechanism),
+	 * SAS_HA_FROZEN gives eh dominion over all sas_task completion.
+	 */
+	set_bit(SAS_HA_FROZEN, &ha->state);
+	sas_eh_handle_sas_errors(shost, &eh_work_q);
+	clear_bit(SAS_HA_FROZEN, &ha->state);
+	if (list_empty(&eh_work_q))
+		goto out;
+
+	/*
+	 * Now deal with SCSI commands that completed ok but have a an error
+	 * code (and hopefully sense data) attached.  This is roughly what
+	 * scsi_unjam_host does, but we skip scsi_eh_abort_cmds because any
+	 * command we see here has no sas_task and is thus unknown to the HA.
+	 */
+	sas_ata_eh(shost, &eh_work_q, &ha->eh_done_q);
+	if (!scsi_eh_get_sense(&eh_work_q, &ha->eh_done_q))
+		scsi_eh_ready_devs(shost, &eh_work_q, &ha->eh_done_q);
+
+out:
+	sas_eh_handle_resets(shost);
+
+	/* now link into libata eh --- if we have any ata devices */
+	sas_ata_strategy_handler(shost);
+
+	scsi_eh_flush_done_q(&ha->eh_done_q);
+
+	/* check if any new eh work was scheduled during the last run */
+	spin_lock_irq(&ha->lock);
+	if (ha->eh_active == 0) {
+		shost->host_eh_scheduled = 0;
+		retry = false;
+	}
+	spin_unlock_irq(&ha->lock);
+
+	if (retry)
+		goto retry;
+
+	pr_notice("--- Exit %s: busy: %d failed: %d tries: %d\n",
+		  __func__, scsi_host_busy(shost),
+		  shost->host_failed, tries);
+}
+
+int sas_ioctl(struct scsi_device *sdev, unsigned int cmd, void __user *arg)
+{
+	struct domain_device *dev = sdev_to_domain_dev(sdev);
+
+	if (dev_is_sata(dev))
+		return ata_sas_scsi_ioctl(dev->sata_dev.ap, sdev, cmd, arg);
+
+	return -EINVAL;
+}
+
+struct domain_device *sas_find_dev_by_rphy(struct sas_rphy *rphy)
+{
+	struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent);
+	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	struct domain_device *found_dev = NULL;
+	int i;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ha->phy_port_lock, flags);
+	for (i = 0; i < ha->num_phys; i++) {
+		struct asd_sas_port *port = ha->sas_port[i];
+		struct domain_device *dev;
+
+		spin_lock(&port->dev_list_lock);
+		list_for_each_entry(dev, &port->dev_list, dev_list_node) {
+			if (rphy == dev->rphy) {
+				found_dev = dev;
+				spin_unlock(&port->dev_list_lock);
+				goto found;
+			}
+		}
+		spin_unlock(&port->dev_list_lock);
+	}
+ found:
+	spin_unlock_irqrestore(&ha->phy_port_lock, flags);
+
+	return found_dev;
+}
+
+int sas_target_alloc(struct scsi_target *starget)
+{
+	struct sas_rphy *rphy = dev_to_rphy(starget->dev.parent);
+	struct domain_device *found_dev = sas_find_dev_by_rphy(rphy);
+
+	if (!found_dev)
+		return -ENODEV;
+
+	kref_get(&found_dev->kref);
+	starget->hostdata = found_dev;
+	return 0;
+}
+
+#define SAS_DEF_QD 256
+
+int sas_slave_configure(struct scsi_device *scsi_dev)
+{
+	struct domain_device *dev = sdev_to_domain_dev(scsi_dev);
+
+	BUG_ON(dev->rphy->identify.device_type != SAS_END_DEVICE);
+
+	if (dev_is_sata(dev)) {
+		ata_sas_slave_configure(scsi_dev, dev->sata_dev.ap);
+		return 0;
+	}
+
+	sas_read_port_mode_page(scsi_dev);
+
+	if (scsi_dev->tagged_supported) {
+		scsi_change_queue_depth(scsi_dev, SAS_DEF_QD);
+	} else {
+		pr_notice("device %016llx, LUN 0x%llx doesn't support TCQ\n",
+			  SAS_ADDR(dev->sas_addr), scsi_dev->lun);
+		scsi_change_queue_depth(scsi_dev, 1);
+	}
+
+	scsi_dev->allow_restart = 1;
+
+	return 0;
+}
+
+int sas_change_queue_depth(struct scsi_device *sdev, int depth)
+{
+	struct domain_device *dev = sdev_to_domain_dev(sdev);
+
+	if (dev_is_sata(dev))
+		return __ata_change_queue_depth(dev->sata_dev.ap, sdev, depth);
+
+	if (!sdev->tagged_supported)
+		depth = 1;
+	return scsi_change_queue_depth(sdev, depth);
+}
+
+int sas_bios_param(struct scsi_device *scsi_dev,
+			  struct block_device *bdev,
+			  sector_t capacity, int *hsc)
+{
+	hsc[0] = 255;
+	hsc[1] = 63;
+	sector_div(capacity, 255*63);
+	hsc[2] = capacity;
+
+	return 0;
+}
+
+/*
+ * Tell an upper layer that it needs to initiate an abort for a given task.
+ * This should only ever be called by an LLDD.
+ */
+void sas_task_abort(struct sas_task *task)
+{
+	struct scsi_cmnd *sc = task->uldd_task;
+
+	/* Escape for libsas internal commands */
+	if (!sc) {
+		struct sas_task_slow *slow = task->slow_task;
+
+		if (!slow)
+			return;
+		if (!del_timer(&slow->timer))
+			return;
+		slow->timer.function(&slow->timer);
+		return;
+	}
+
+	if (dev_is_sata(task->dev))
+		sas_ata_task_abort(task);
+	else
+		blk_abort_request(sc->request);
+}
+
+int sas_slave_alloc(struct scsi_device *sdev)
+{
+	if (dev_is_sata(sdev_to_domain_dev(sdev)) && sdev->lun)
+		return -ENXIO;
+
+	return 0;
+}
+
+void sas_target_destroy(struct scsi_target *starget)
+{
+	struct domain_device *found_dev = starget->hostdata;
+
+	if (!found_dev)
+		return;
+
+	starget->hostdata = NULL;
+	sas_put_device(found_dev);
+}
+
+#define SAS_STRING_ADDR_SIZE	16
+
+int sas_request_addr(struct Scsi_Host *shost, u8 *addr)
+{
+	int res;
+	const struct firmware *fw;
+
+	res = request_firmware(&fw, "sas_addr", &shost->shost_gendev);
+	if (res)
+		return res;
+
+	if (fw->size < SAS_STRING_ADDR_SIZE) {
+		res = -ENODEV;
+		goto out;
+	}
+
+	res = hex2bin(addr, fw->data, strnlen(fw->data, SAS_ADDR_SIZE * 2) / 2);
+	if (res)
+		goto out;
+
+out:
+	release_firmware(fw);
+	return res;
+}
+EXPORT_SYMBOL_GPL(sas_request_addr);
+
+EXPORT_SYMBOL_GPL(sas_queuecommand);
+EXPORT_SYMBOL_GPL(sas_target_alloc);
+EXPORT_SYMBOL_GPL(sas_slave_configure);
+EXPORT_SYMBOL_GPL(sas_change_queue_depth);
+EXPORT_SYMBOL_GPL(sas_bios_param);
+EXPORT_SYMBOL_GPL(sas_task_abort);
+EXPORT_SYMBOL_GPL(sas_phy_reset);
+EXPORT_SYMBOL_GPL(sas_eh_device_reset_handler);
+EXPORT_SYMBOL_GPL(sas_eh_target_reset_handler);
+EXPORT_SYMBOL_GPL(sas_slave_alloc);
+EXPORT_SYMBOL_GPL(sas_target_destroy);
+EXPORT_SYMBOL_GPL(sas_ioctl);
diff --git a/drivers/scsi/libsas/sas_task.c b/drivers/scsi/libsas/sas_task.c
new file mode 100644
index 000000000..2966ead1d
--- /dev/null
+++ b/drivers/scsi/libsas/sas_task.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "sas_internal.h"
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <scsi/sas.h>
+#include <scsi/libsas.h>
+
+/* fill task_status_struct based on SSP response frame */
+void sas_ssp_task_response(struct device *dev, struct sas_task *task,
+			   struct ssp_response_iu *iu)
+{
+	struct task_status_struct *tstat = &task->task_status;
+
+	tstat->resp = SAS_TASK_COMPLETE;
+
+	if (iu->datapres == 0)
+		tstat->stat = iu->status;
+	else if (iu->datapres == 1)
+		tstat->stat = iu->resp_data[3];
+	else if (iu->datapres == 2) {
+		tstat->stat = SAS_SAM_STAT_CHECK_CONDITION;
+		tstat->buf_valid_size =
+			min_t(int, SAS_STATUS_BUF_SIZE,
+			      be32_to_cpu(iu->sense_data_len));
+		memcpy(tstat->buf, iu->sense_data, tstat->buf_valid_size);
+
+		if (iu->status != SAM_STAT_CHECK_CONDITION)
+			dev_warn(dev, "dev %016llx sent sense data, but stat(0x%x) is not CHECK CONDITION\n",
+				 SAS_ADDR(task->dev->sas_addr), iu->status);
+	}
+	else
+		/* when datapres contains corrupt/unknown value... */
+		tstat->stat = SAS_SAM_STAT_CHECK_CONDITION;
+}
+EXPORT_SYMBOL_GPL(sas_ssp_task_response);
+