Merge branch 'perf/core' into perf/uprobes

Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 397 insertions, 431 deletions

diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
index db9238f2ecb..bc0cecc6ad6 100644
--- a/drivers/scsi/libsas/sas_ata.c
+++ b/drivers/scsi/libsas/sas_ata.c
@@ -23,6 +23,8 @@
 
 #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"
@@ -93,22 +95,47 @@ static enum ata_completion_errors sas_to_ata_err(struct task_status_struct *ts)
 static void sas_ata_task_done(struct sas_task *task)
 {
 	struct ata_queued_cmd *qc = task->uldd_task;
-	struct domain_device *dev;
+	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;
+	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;
 
-	dev = qc->ap->private_data;
-	sas_ha = dev->port->ha;
-	link = &dev->sata_dev.ap->link;
+	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;
+		}
+	}
 
-	spin_lock_irqsave(dev->sata_dev.ap->lock, flags);
 	if (stat->stat == SAS_PROTO_RESPONSE || stat->stat == SAM_STAT_GOOD ||
 	    ((stat->stat == SAM_STAT_CHECK_CONDITION &&
 	      dev->sata_dev.command_set == ATAPI_COMMAND_SET))) {
@@ -121,10 +148,6 @@ static void sas_ata_task_done(struct sas_task *task)
 			if (unlikely(link->eh_info.err_mask))
 				qc->flags |= ATA_QCFLAG_FAILED;
 		}
-
-		dev->sata_dev.sstatus = resp->sstatus;
-		dev->sata_dev.serror = resp->serror;
-		dev->sata_dev.scontrol = resp->scontrol;
 	} else {
 		ac = sas_to_ata_err(stat);
 		if (ac) {
@@ -144,24 +167,8 @@ static void sas_ata_task_done(struct sas_task *task)
 	}
 
 	qc->lldd_task = NULL;
-	if (qc->scsicmd)
-		ASSIGN_SAS_TASK(qc->scsicmd, NULL);
 	ata_qc_complete(qc);
-	spin_unlock_irqrestore(dev->sata_dev.ap->lock, flags);
-
-	/*
-	 * If the sas_task has an ata qc, a scsi_cmnd and the aborted
-	 * flag is set, then we must have come in via the libsas EH
-	 * functions.  When we exit this function, we need to put the
-	 * scsi_cmnd on the list of finished errors.  The ata_qc_complete
-	 * call cleans up the libata side of things but we're protected
-	 * from the scsi_cmnd going away because the scsi_cmnd is owned
-	 * by the EH, making libata's call to scsi_done a NOP.
-	 */
-	spin_lock_irqsave(&task->task_state_lock, flags);
-	if (qc->scsicmd && task->task_state_flags & SAS_TASK_STATE_ABORTED)
-		scsi_eh_finish_cmd(qc->scsicmd, &sas_ha->eh_done_q);
-	spin_unlock_irqrestore(&task->task_state_lock, flags);
+	spin_unlock_irqrestore(ap->lock, flags);
 
 qc_already_gone:
 	list_del_init(&task->list);
@@ -170,23 +177,30 @@ qc_already_gone:
 
 static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
 {
-	int res;
+	unsigned long flags;
 	struct sas_task *task;
-	struct domain_device *dev = qc->ap->private_data;
+	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);
-	struct scatterlist *sg;
-	unsigned int xfer = 0;
-	unsigned int si;
+
+	/* TODO: audit callers to ensure they are ready for qc_issue to
+	 * unconditionally re-enable interrupts
+	 */
+	local_irq_save(flags);
+	spin_unlock(ap->lock);
 
 	/* If the device fell off, no sense in issuing commands */
-	if (dev->gone)
-		return AC_ERR_SYSTEM;
+	if (test_bit(SAS_DEV_GONE, &dev->state))
+		goto out;
 
 	task = sas_alloc_task(GFP_ATOMIC);
 	if (!task)
-		return AC_ERR_SYSTEM;
+		goto out;
 	task->dev = dev;
 	task->task_proto = SAS_PROTOCOL_STP;
 	task->task_done = sas_ata_task_done;
@@ -231,21 +245,24 @@ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
 		ASSIGN_SAS_TASK(qc->scsicmd, task);
 
 	if (sas_ha->lldd_max_execute_num < 2)
-		res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
+		ret = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
 	else
-		res = sas_queue_up(task);
+		ret = sas_queue_up(task);
 
 	/* Examine */
-	if (res) {
-		SAS_DPRINTK("lldd_execute_task returned: %d\n", res);
+	if (ret) {
+		SAS_DPRINTK("lldd_execute_task returned: %d\n", ret);
 
 		if (qc->scsicmd)
 			ASSIGN_SAS_TASK(qc->scsicmd, NULL);
 		sas_free_task(task);
-		return AC_ERR_SYSTEM;
+		ret = AC_ERR_SYSTEM;
 	}
 
-	return 0;
+ out:
+	spin_lock(ap->lock);
+	local_irq_restore(flags);
+	return ret;
 }
 
 static bool sas_ata_qc_fill_rtf(struct ata_queued_cmd *qc)
@@ -256,83 +273,222 @@ static bool sas_ata_qc_fill_rtf(struct ata_queued_cmd *qc)
 	return true;
 }
 
-static int sas_ata_hard_reset(struct ata_link *link, unsigned int *class,
-			       unsigned long deadline)
+static struct sas_internal *dev_to_sas_internal(struct domain_device *dev)
+{
+	return to_sas_internal(dev->port->ha->core.shost->transportt);
+}
+
+static void 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 |= SATA_DEV;
+
+	if (phy->attached_dev_type == SATA_PENDING)
+		dev->dev_type = SATA_PENDING;
+	else {
+		int res;
+
+		dev->dev_type = SATA_DEV;
+		res = sas_get_report_phy_sata(dev->parent, phy->phy_id,
+					      &dev->sata_dev.rps_resp);
+		if (res) {
+			SAS_DPRINTK("report phy sata to %016llx:0x%x 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));
+		/* TODO switch to ata_dev_classify() */
+		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 != 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 sas_internal *i =
-		to_sas_internal(dev->port->ha->core.shost->transportt);
-	int res = TMF_RESP_FUNC_FAILED;
-	int ret = 0;
+	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];
 
-	if (i->dft->lldd_I_T_nexus_reset)
-		res = i->dft->lldd_I_T_nexus_reset(dev);
+	res = sas_ex_phy_discover(ex_dev, phy->number);
+	sas_put_local_phy(phy);
 
-	if (res != TMF_RESP_FUNC_COMPLETE) {
-		SAS_DPRINTK("%s: Unable to reset I T nexus?\n", __func__);
-		ret = -EAGAIN;
+	/* 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 SATA_PENDING:
+		return 0;
+	case SAS_END_DEV:
+		if (ex_phy->attached_sata_dev)
+			return sas_ata_clear_pending(dev, ex_phy);
+	default:
+		return -ENODEV;
 	}
+}
 
-	switch (dev->sata_dev.command_set) {
-		case ATA_COMMAND_SET:
-			SAS_DPRINTK("%s: Found ATA device.\n", __func__);
-			*class = ATA_DEV_ATA;
-			break;
-		case ATAPI_COMMAND_SET:
-			SAS_DPRINTK("%s: Found ATAPI device.\n", __func__);
-			*class = ATA_DEV_ATAPI;
-			break;
-		default:
-			SAS_DPRINTK("%s: Unknown SATA command set: %d.\n",
-				    __func__,
-				    dev->sata_dev.command_set);
-			*class = ATA_DEV_UNKNOWN;
-			break;
+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;
 	}
+}
 
-	ap->cbl = ATA_CBL_SATA;
-	return ret;
+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("%ssas: ata%u: %s: %pV",
+		   level, ap->print_id, dev_name(dev), &vaf);
+
+	va_end(args);
+
+	return r;
 }
 
-static int sas_ata_soft_reset(struct ata_link *link, unsigned int *class,
-			       unsigned long deadline)
+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 =
-		to_sas_internal(dev->port->ha->core.shost->transportt);
-	int res = TMF_RESP_FUNC_FAILED;
-	int ret = 0;
+	struct sas_internal *i = dev_to_sas_internal(dev);
 
-	if (i->dft->lldd_ata_soft_reset)
-		res = i->dft->lldd_ata_soft_reset(dev);
+	res = i->dft->lldd_I_T_nexus_reset(dev);
+	if (res == -ENODEV)
+		return res;
 
-	if (res != TMF_RESP_FUNC_COMPLETE) {
-		SAS_DPRINTK("%s: Unable to soft reset\n", __func__);
-		ret = -EAGAIN;
-	}
+	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);
 
+	/* XXX: if the class changes during the reset the upper layer
+	 * should be informed, if the device has gone away we assume
+	 * libsas will eventually delete it
+	 */
 	switch (dev->sata_dev.command_set) {
 	case ATA_COMMAND_SET:
-		SAS_DPRINTK("%s: Found ATA device.\n", __func__);
 		*class = ATA_DEV_ATA;
 		break;
 	case ATAPI_COMMAND_SET:
-		SAS_DPRINTK("%s: Found ATAPI device.\n", __func__);
 		*class = ATA_DEV_ATAPI;
 		break;
-	default:
-		SAS_DPRINTK("%s: Unknown SATA command set: %d.\n",
-			    __func__, dev->sata_dev.command_set);
-		*class = ATA_DEV_UNKNOWN;
-		break;
 	}
 
 	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);
+		SAS_DPRINTK("%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
+	 */
+	SAS_DPRINTK("%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:
+	list_del_init(&task->list);
+	sas_free_task(task);
+}
+
 static void sas_ata_post_internal(struct ata_queued_cmd *qc)
 {
 	if (qc->flags & ATA_QCFLAG_FAILED)
@@ -340,30 +496,35 @@ static void sas_ata_post_internal(struct ata_queued_cmd *qc)
 
 	if (qc->err_mask) {
 		/*
-		 * Find the sas_task and kill it.  By this point,
-		 * libata has decided to kill the qc, so we needn't
-		 * bother with sas_ata_task_done.  But we still
-		 * ought to abort the task.
+		 * 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;
-		unsigned long flags;
 
 		qc->lldd_task = NULL;
-		if (task) {
-			/* Should this be a AT(API) device reset? */
-			spin_lock_irqsave(&task->task_state_lock, flags);
-			task->task_state_flags |= SAS_TASK_NEED_DEV_RESET;
-			spin_unlock_irqrestore(&task->task_state_lock, flags);
-
-			task->uldd_task = NULL;
-			__sas_task_abort(task);
-		}
+		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 struct ata_port_operations sas_sata_ops = {
 	.prereset		= ata_std_prereset,
-	.softreset		= sas_ata_soft_reset,
 	.hardreset		= sas_ata_hard_reset,
 	.postreset		= ata_std_postreset,
 	.error_handler		= ata_std_error_handler,
@@ -374,6 +535,7 @@ static struct ata_port_operations sas_sata_ops = {
 	.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,
 };
 
 static struct ata_port_info sata_port_info = {
@@ -384,11 +546,10 @@ static struct ata_port_info sata_port_info = {
 	.port_ops = &sas_sata_ops
 };
 
-int sas_ata_init_host_and_port(struct domain_device *found_dev,
-			       struct scsi_target *starget)
+int sas_ata_init_host_and_port(struct domain_device *found_dev)
 {
-	struct Scsi_Host *shost = dev_to_shost(&starget->dev);
-	struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
+	struct sas_ha_struct *ha = found_dev->port->ha;
+	struct Scsi_Host *shost = ha->core.shost;
 	struct ata_port *ap;
 
 	ata_host_init(&found_dev->sata_dev.ata_host,
@@ -406,6 +567,8 @@ int sas_ata_init_host_and_port(struct domain_device *found_dev,
 	ap->private_data = found_dev;
 	ap->cbl = ATA_CBL_SATA;
 	ap->scsi_host = shost;
+	/* publish initialized ata port */
+	smp_wmb();
 	found_dev->sata_dev.ap = ap;
 
 	return 0;
@@ -436,168 +599,14 @@ void sas_ata_task_abort(struct sas_task *task)
 	complete(waiting);
 }
 
-static void sas_task_timedout(unsigned long _task)
-{
-	struct sas_task *task = (void *) _task;
-	unsigned long flags;
-
-	spin_lock_irqsave(&task->task_state_lock, flags);
-	if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
-		task->task_state_flags |= SAS_TASK_STATE_ABORTED;
-	spin_unlock_irqrestore(&task->task_state_lock, flags);
-
-	complete(&task->completion);
-}
-
-static void sas_disc_task_done(struct sas_task *task)
-{
-	if (!del_timer(&task->timer))
-		return;
-	complete(&task->completion);
-}
-
-#define SAS_DEV_TIMEOUT 10
-
-/**
- * sas_execute_task -- Basic task processing for discovery
- * @task: the task to be executed
- * @buffer: pointer to buffer to do I/O
- * @size: size of @buffer
- * @dma_dir: DMA direction.  DMA_xxx
- */
-static int sas_execute_task(struct sas_task *task, void *buffer, int size,
-			    enum dma_data_direction dma_dir)
-{
-	int res = 0;
-	struct scatterlist *scatter = NULL;
-	struct task_status_struct *ts = &task->task_status;
-	int num_scatter = 0;
-	int retries = 0;
-	struct sas_internal *i =
-		to_sas_internal(task->dev->port->ha->core.shost->transportt);
-
-	if (dma_dir != DMA_NONE) {
-		scatter = kzalloc(sizeof(*scatter), GFP_KERNEL);
-		if (!scatter)
-			goto out;
-
-		sg_init_one(scatter, buffer, size);
-		num_scatter = 1;
-	}
-
-	task->task_proto = task->dev->tproto;
-	task->scatter = scatter;
-	task->num_scatter = num_scatter;
-	task->total_xfer_len = size;
-	task->data_dir = dma_dir;
-	task->task_done = sas_disc_task_done;
-	if (dma_dir != DMA_NONE &&
-	    sas_protocol_ata(task->task_proto)) {
-		task->num_scatter = dma_map_sg(task->dev->port->ha->dev,
-					       task->scatter,
-					       task->num_scatter,
-					       task->data_dir);
-	}
-
-	for (retries = 0; retries < 5; retries++) {
-		task->task_state_flags = SAS_TASK_STATE_PENDING;
-		init_completion(&task->completion);
-
-		task->timer.data = (unsigned long) task;
-		task->timer.function = sas_task_timedout;
-		task->timer.expires = jiffies + SAS_DEV_TIMEOUT*HZ;
-		add_timer(&task->timer);
-
-		res = i->dft->lldd_execute_task(task, 1, GFP_KERNEL);
-		if (res) {
-			del_timer(&task->timer);
-			SAS_DPRINTK("executing SAS discovery task failed:%d\n",
-				    res);
-			goto ex_err;
-		}
-		wait_for_completion(&task->completion);
-		res = -ECOMM;
-		if (task->task_state_flags & SAS_TASK_STATE_ABORTED) {
-			int res2;
-			SAS_DPRINTK("task aborted, flags:0x%x\n",
-				    task->task_state_flags);
-			res2 = i->dft->lldd_abort_task(task);
-			SAS_DPRINTK("came back from abort task\n");
-			if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
-				if (res2 == TMF_RESP_FUNC_COMPLETE)
-					continue; /* Retry the task */
-				else
-					goto ex_err;
-			}
-		}
-		if (task->task_status.stat == SAM_STAT_BUSY ||
-			   task->task_status.stat == SAM_STAT_TASK_SET_FULL ||
-			   task->task_status.stat == SAS_QUEUE_FULL) {
-			SAS_DPRINTK("task: q busy, sleeping...\n");
-			schedule_timeout_interruptible(HZ);
-		} else if (task->task_status.stat == SAM_STAT_CHECK_CONDITION) {
-			struct scsi_sense_hdr shdr;
-
-			if (!scsi_normalize_sense(ts->buf, ts->buf_valid_size,
-						  &shdr)) {
-				SAS_DPRINTK("couldn't normalize sense\n");
-				continue;
-			}
-			if ((shdr.sense_key == 6 && shdr.asc == 0x29) ||
-			    (shdr.sense_key == 2 && shdr.asc == 4 &&
-			     shdr.ascq == 1)) {
-				SAS_DPRINTK("device %016llx LUN: %016llx "
-					    "powering up or not ready yet, "
-					    "sleeping...\n",
-					    SAS_ADDR(task->dev->sas_addr),
-					    SAS_ADDR(task->ssp_task.LUN));
-
-				schedule_timeout_interruptible(5*HZ);
-			} else if (shdr.sense_key == 1) {
-				res = 0;
-				break;
-			} else if (shdr.sense_key == 5) {
-				break;
-			} else {
-				SAS_DPRINTK("dev %016llx LUN: %016llx "
-					    "sense key:0x%x ASC:0x%x ASCQ:0x%x"
-					    "\n",
-					    SAS_ADDR(task->dev->sas_addr),
-					    SAS_ADDR(task->ssp_task.LUN),
-					    shdr.sense_key,
-					    shdr.asc, shdr.ascq);
-			}
-		} else if (task->task_status.resp != SAS_TASK_COMPLETE ||
-			   task->task_status.stat != SAM_STAT_GOOD) {
-			SAS_DPRINTK("task finished with resp:0x%x, "
-				    "stat:0x%x\n",
-				    task->task_status.resp,
-				    task->task_status.stat);
-			goto ex_err;
-		} else {
-			res = 0;
-			break;
-		}
-	}
-ex_err:
-	if (dma_dir != DMA_NONE) {
-		if (sas_protocol_ata(task->task_proto))
-			dma_unmap_sg(task->dev->port->ha->dev,
-				     task->scatter, task->num_scatter,
-				     task->data_dir);
-		kfree(scatter);
-	}
-out:
-	return res;
-}
-
-/* ---------- SATA ---------- */
-
 static void sas_get_ata_command_set(struct domain_device *dev)
 {
 	struct dev_to_host_fis *fis =
 		(struct dev_to_host_fis *) dev->frame_rcvd;
 
+	if (dev->dev_type == SATA_PENDING)
+		return;
+
 	if ((fis->sector_count == 1 && /* ATA */
 	     fis->lbal         == 1 &&
 	     fis->lbam         == 0 &&
@@ -636,224 +645,152 @@ static void sas_get_ata_command_set(struct domain_device *dev)
 		dev->sata_dev.command_set = ATAPI_COMMAND_SET;
 }
 
-/**
- * sas_issue_ata_cmd -- Basic SATA command processing for discovery
- * @dev: the device to send the command to
- * @command: the command register
- * @features: the features register
- * @buffer: pointer to buffer to do I/O
- * @size: size of @buffer
- * @dma_dir: DMA direction.  DMA_xxx
- */
-static int sas_issue_ata_cmd(struct domain_device *dev, u8 command,
-			     u8 features, void *buffer, int size,
-			     enum dma_data_direction dma_dir)
-{
-	int res = 0;
-	struct sas_task *task;
-	struct dev_to_host_fis *d2h_fis = (struct dev_to_host_fis *)
-		&dev->frame_rcvd[0];
-
-	res = -ENOMEM;
-	task = sas_alloc_task(GFP_KERNEL);
-	if (!task)
-		goto out;
-
-	task->dev = dev;
-
-	task->ata_task.fis.fis_type = 0x27;
-	task->ata_task.fis.command = command;
-	task->ata_task.fis.features = features;
-	task->ata_task.fis.device = d2h_fis->device;
-	task->ata_task.retry_count = 1;
-
-	res = sas_execute_task(task, buffer, size, dma_dir);
-
-	sas_free_task(task);
-out:
-	return res;
-}
-
-#define ATA_IDENTIFY_DEV         0xEC
-#define ATA_IDENTIFY_PACKET_DEV  0xA1
-#define ATA_SET_FEATURES         0xEF
-#define ATA_FEATURE_PUP_STBY_SPIN_UP 0x07
-
-/**
- * sas_discover_sata_dev -- discover a STP/SATA device (SATA_DEV)
- * @dev: STP/SATA device of interest (ATA/ATAPI)
- *
- * The LLDD has already been notified of this device, so that we can
- * send FISes to it.  Here we try to get IDENTIFY DEVICE or IDENTIFY
- * PACKET DEVICE, if ATAPI device, so that the LLDD can fine-tune its
- * performance for this device.
- */
-static int sas_discover_sata_dev(struct domain_device *dev)
+void sas_probe_sata(struct asd_sas_port *port)
 {
-	int     res;
-	__le16  *identify_x;
-	u8      command;
+	struct domain_device *dev, *n;
+	int err;
 
-	identify_x = kzalloc(512, GFP_KERNEL);
-	if (!identify_x)
-		return -ENOMEM;
-
-	if (dev->sata_dev.command_set == ATA_COMMAND_SET) {
-		dev->sata_dev.identify_device = identify_x;
-		command = ATA_IDENTIFY_DEV;
-	} else {
-		dev->sata_dev.identify_packet_device = identify_x;
-		command = ATA_IDENTIFY_PACKET_DEV;
-	}
+	mutex_lock(&port->ha->disco_mutex);
+	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
+		if (!dev_is_sata(dev))
+			continue;
 
-	res = sas_issue_ata_cmd(dev, command, 0, identify_x, 512,
-				DMA_FROM_DEVICE);
-	if (res)
-		goto out_err;
-
-	/* lives on the media? */
-	if (le16_to_cpu(identify_x[0]) & 4) {
-		/* incomplete response */
-		SAS_DPRINTK("sending SET FEATURE/PUP_STBY_SPIN_UP to "
-			    "dev %llx\n", SAS_ADDR(dev->sas_addr));
-		if (!(identify_x[83] & cpu_to_le16(1<<6)))
-			goto cont1;
-		res = sas_issue_ata_cmd(dev, ATA_SET_FEATURES,
-					ATA_FEATURE_PUP_STBY_SPIN_UP,
-					NULL, 0, DMA_NONE);
-		if (res)
-			goto cont1;
-
-		schedule_timeout_interruptible(5*HZ); /* More time? */
-		res = sas_issue_ata_cmd(dev, command, 0, identify_x, 512,
-					DMA_FROM_DEVICE);
-		if (res)
-			goto out_err;
+		err = sas_ata_init_host_and_port(dev);
+		if (err)
+			sas_fail_probe(dev, __func__, err);
+		else
+			ata_sas_async_port_init(dev->sata_dev.ap);
 	}
-cont1:
-	/* XXX Hint: register this SATA device with SATL.
-	   When this returns, dev->sata_dev->lu is alive and
-	   present.
-	sas_satl_register_dev(dev);
-	*/
+	mutex_unlock(&port->ha->disco_mutex);
 
-	sas_fill_in_rphy(dev, dev->rphy);
+	list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
+		if (!dev_is_sata(dev))
+			continue;
 
-	return 0;
-out_err:
-	dev->sata_dev.identify_packet_device = NULL;
-	dev->sata_dev.identify_device = NULL;
-	kfree(identify_x);
-	return res;
-}
+		sas_ata_wait_eh(dev);
 
-static int sas_discover_sata_pm(struct domain_device *dev)
-{
-	return -ENODEV;
+		/* if libata could not bring the link up, don't surface
+		 * the device
+		 */
+		if (ata_dev_disabled(sas_to_ata_dev(dev)))
+			sas_fail_probe(dev, __func__, -ENODEV);
+	}
 }
 
 /**
  * sas_discover_sata -- discover an STP/SATA domain device
  * @dev: pointer to struct domain_device of interest
  *
- * First we notify the LLDD of this device, so we can send frames to
- * it.  Then depending on the type of device we call the appropriate
- * discover functions.  Once device discover is done, we notify the
- * LLDD so that it can fine-tune its parameters for the device, by
- * removing it and then adding it.  That is, the second time around,
- * the driver would have certain fields, that it is looking at, set.
- * Finally we initialize the kobj so that the device can be added to
- * the system at registration time.  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.
+ * 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)
 {
 	int res;
 
+	if (dev->dev_type == SATA_PM)
+		return -ENODEV;
+
 	sas_get_ata_command_set(dev);
+	sas_fill_in_rphy(dev, dev->rphy);
 
 	res = sas_notify_lldd_dev_found(dev);
 	if (res)
 		return res;
 
-	switch (dev->dev_type) {
-	case SATA_DEV:
-		res = sas_discover_sata_dev(dev);
-		break;
-	case SATA_PM:
-		res = sas_discover_sata_pm(dev);
-		break;
-	default:
-		break;
-	}
-	sas_notify_lldd_dev_gone(dev);
-	if (!res) {
-		sas_notify_lldd_dev_found(dev);
-		res = sas_rphy_add(dev->rphy);
-	}
-
-	return res;
+	sas_discover_event(dev->port, DISCE_PROBE);
+	return 0;
 }
 
-void sas_ata_strategy_handler(struct Scsi_Host *shost)
+static void async_sas_ata_eh(void *data, async_cookie_t cookie)
 {
-	struct scsi_device *sdev;
+	struct domain_device *dev = data;
+	struct ata_port *ap = dev->sata_dev.ap;
+	struct sas_ha_struct *ha = dev->port->ha;
 
-	shost_for_each_device(sdev, shost) {
-		struct domain_device *ddev = sdev_to_domain_dev(sdev);
-		struct ata_port *ap = ddev->sata_dev.ap;
+	/* hold a reference over eh since we may be racing with final
+	 * remove once all commands are completed
+	 */
+	kref_get(&dev->kref);
+	sas_ata_printk(KERN_DEBUG, dev, "dev error handler\n");
+	ata_scsi_port_error_handler(ha->core.shost, ap);
+	sas_put_device(dev);
+}
 
-		if (!dev_is_sata(ddev))
-			continue;
+static bool sas_ata_dev_eh_valid(struct domain_device *dev)
+{
+	struct ata_port *ap;
 
-		ata_port_printk(ap, KERN_DEBUG, "sas eh calling libata port error handler");
-		ata_scsi_port_error_handler(shost, ap);
-	}
+	if (!dev_is_sata(dev))
+		return false;
+	ap = dev->sata_dev.ap;
+	/* consume fully initialized ata ports */
+	smp_rmb();
+	return !!ap;
 }
 
-int sas_ata_timed_out(struct scsi_cmnd *cmd, struct sas_task *task,
-		      enum blk_eh_timer_return *rtn)
+void sas_ata_strategy_handler(struct Scsi_Host *shost)
 {
-	struct domain_device *ddev = cmd_to_domain_dev(cmd);
+	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+	LIST_HEAD(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);
 
-	if (!dev_is_sata(ddev) || task)
-		return 0;
+	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;
 
-	/* we're a sata device with no task, so this must be a libata
-	 * eh timeout.  Ideally should hook into libata timeout
-	 * handling, but there's no point, it just wants to activate
-	 * the eh thread */
-	*rtn = BLK_EH_NOT_HANDLED;
-	return 1;
+		spin_lock(&port->dev_list_lock);
+		list_for_each_entry(dev, &port->dev_list, dev_list_node) {
+			if (!sas_ata_dev_eh_valid(dev))
+				continue;
+			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);
 }
 
-int sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q,
-	       struct list_head *done_q)
+void sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q,
+		struct list_head *done_q)
 {
-	int rtn = 0;
 	struct scsi_cmnd *cmd, *n;
-	struct ata_port *ap;
+	struct domain_device *eh_dev;
 
 	do {
 		LIST_HEAD(sata_q);
-
-		ap = NULL;
+		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 (ap && ap != ddev->sata_dev.ap)
+			if (eh_dev && eh_dev != ddev)
 				continue;
-			ap = ddev->sata_dev.ap;
-			rtn = 1;
+			eh_dev = ddev;
 			list_move(&cmd->eh_entry, &sata_q);
 		}
 
 		if (!list_empty(&sata_q)) {
-			ata_port_printk(ap, KERN_DEBUG, "sas eh calling libata cmd error handler\n");
+			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
@@ -869,7 +806,36 @@ int sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q,
 			while (!list_empty(&sata_q))
 				list_del_init(sata_q.next);
 		}
-	} while (ap);
+	} 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;
 
-	return rtn;
+	ap = dev->sata_dev.ap;
+	ata_port_wait_eh(ap);
 }