1 files changed, 258 insertions, 1 deletions

diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c
index 69f17b98e4fa..709c08171743 100644
--- a/drivers/scsi/isci/task.c
+++ b/drivers/scsi/isci/task.c
@@ -56,6 +56,7 @@
 #include <linux/completion.h>
 #include <linux/irqflags.h>
 #include "sas.h"
+#include <scsi/libsas.h>
 #include "remote_device.h"
 #include "remote_node_context.h"
 #include "isci.h"
@@ -1397,11 +1398,250 @@ isci_task_request_complete(struct isci_host *ihost,
         complete(tmf_complete);
 }
 
+static void isci_smp_task_timedout(unsigned long _task)
+{
+        struct sas_task *task = (void *) _task;
+        unsigned long flags;
+
+        spin_lock_irqsave(&task->task_state_lock, flags);
+        if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
+                task->task_state_flags |= SAS_TASK_STATE_ABORTED;
+        spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+        complete(&task->completion);
+}
+
+static void isci_smp_task_done(struct sas_task *task)
+{
+        if (!del_timer(&task->timer))
+                return;
+        complete(&task->completion);
+}
+
+static struct sas_task *isci_alloc_task(void)
+{
+        struct sas_task *task = kzalloc(sizeof(*task), GFP_KERNEL);
+
+        if (task) {
+                INIT_LIST_HEAD(&task->list);
+                spin_lock_init(&task->task_state_lock);
+                task->task_state_flags = SAS_TASK_STATE_PENDING;
+                init_timer(&task->timer);
+                init_completion(&task->completion);
+        }
+
+        return task;
+}
+
+static void isci_free_task(struct isci_host *ihost, struct sas_task  *task)
+{
+        if (task) {
+                BUG_ON(!list_empty(&task->list));
+                kfree(task);
+        }
+}
+
+static int isci_smp_execute_task(struct isci_host *ihost,
+                                 struct domain_device *dev, void *req,
+                                 int req_size, void *resp, int resp_size)
+{
+        int res, retry;
+        struct sas_task *task = NULL;
+
+        for (retry = 0; retry < 3; retry++) {
+                task = isci_alloc_task();
+                if (!task)
+                        return -ENOMEM;
+
+                task->dev = dev;
+                task->task_proto = dev->tproto;
+                sg_init_one(&task->smp_task.smp_req, req, req_size);
+                sg_init_one(&task->smp_task.smp_resp, resp, resp_size);
+
+                task->task_done = isci_smp_task_done;
+
+                task->timer.data = (unsigned long) task;
+                task->timer.function = isci_smp_task_timedout;
+                task->timer.expires = jiffies + 10*HZ;
+                add_timer(&task->timer);
+
+                res = isci_task_execute_task(task, 1, GFP_KERNEL);
+
+                if (res) {
+                        del_timer(&task->timer);
+                        dev_err(&ihost->pdev->dev,
+                                "%s: executing SMP task failed:%d\n",
+                                __func__, res);
+                        goto ex_err;
+                }
+
+                wait_for_completion(&task->completion);
+                res = -ECOMM;
+                if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) {
+                        dev_err(&ihost->pdev->dev,
+                                "%s: smp task timed out or aborted\n",
+                                __func__);
+                        isci_task_abort_task(task);
+                        if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
+                                dev_err(&ihost->pdev->dev,
+                                        "%s: SMP task aborted and not done\n",
+                                        __func__);
+                                goto ex_err;
+                        }
+                }
+                if (task->task_status.resp == SAS_TASK_COMPLETE &&
+                    task->task_status.stat == SAM_STAT_GOOD) {
+                        res = 0;
+                        break;
+                }
+                if (task->task_status.resp == SAS_TASK_COMPLETE &&
+                      task->task_status.stat == SAS_DATA_UNDERRUN) {
+                        /* no error, but return the number of bytes of
+                        * underrun */
+                        res = task->task_status.residual;
+                        break;
+                }
+                if (task->task_status.resp == SAS_TASK_COMPLETE &&
+                      task->task_status.stat == SAS_DATA_OVERRUN) {
+                        res = -EMSGSIZE;
+                        break;
+                } else {
+                        dev_err(&ihost->pdev->dev,
+                                "%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);
+                        isci_free_task(ihost, task);
+                        task = NULL;
+                }
+        }
+ex_err:
+        BUG_ON(retry == 3 && task != NULL);
+        isci_free_task(ihost, task);
+        return res;
+}
+
+#define DISCOVER_REQ_SIZE  16
+#define DISCOVER_RESP_SIZE 56
+
+int isci_smp_get_phy_attached_dev_type(struct isci_host *ihost,
+                                       struct domain_device *dev,
+                                       int phy_id, int *adt)
+{
+        struct smp_resp *disc_resp;
+        u8 *disc_req;
+        int res;
+
+        disc_resp = kzalloc(DISCOVER_RESP_SIZE, GFP_KERNEL);
+        if (!disc_resp)
+                return -ENOMEM;
+
+        disc_req = kzalloc(DISCOVER_REQ_SIZE, GFP_KERNEL);
+        if (disc_req) {
+                disc_req[0] = SMP_REQUEST;
+                disc_req[1] = SMP_DISCOVER;
+                disc_req[9] = phy_id;
+        } else {
+                kfree(disc_resp);
+                return -ENOMEM;
+        }
+        res = isci_smp_execute_task(ihost, dev, disc_req, DISCOVER_REQ_SIZE,
+                                    disc_resp, DISCOVER_RESP_SIZE);
+        if (!res) {
+                if (disc_resp->result != SMP_RESP_FUNC_ACC)
+                        res = disc_resp->result;
+                else
+                        *adt = disc_resp->disc.attached_dev_type;
+        }
+        kfree(disc_req);
+        kfree(disc_resp);
+
+        return res;
+}
+
+static void isci_wait_for_smp_phy_reset(struct isci_remote_device *idev, int phy_num)
+{
+        struct domain_device *dev = idev->domain_dev;
+        struct isci_port *iport = idev->isci_port;
+        struct isci_host *ihost = iport->isci_host;
+        int res, iteration = 0, attached_device_type;
+        #define STP_WAIT_MSECS 25000
+        unsigned long tmo = msecs_to_jiffies(STP_WAIT_MSECS);
+        unsigned long deadline = jiffies + tmo;
+        enum {
+                SMP_PHYWAIT_PHYDOWN,
+                SMP_PHYWAIT_PHYUP,
+                SMP_PHYWAIT_DONE
+        } phy_state = SMP_PHYWAIT_PHYDOWN;
+
+        /* While there is time, wait for the phy to go away and come back */
+        while (time_is_after_jiffies(deadline) && phy_state != SMP_PHYWAIT_DONE) {
+                int event = atomic_read(&iport->event);
+
+                ++iteration;
+
+                tmo = wait_event_timeout(ihost->eventq,
+                                         event != atomic_read(&iport->event) ||
+                                         !test_bit(IPORT_BCN_BLOCKED, &iport->flags),
+                                         tmo);
+                /* link down, stop polling */
+                if (!test_bit(IPORT_BCN_BLOCKED, &iport->flags))
+                        break;
+
+                dev_dbg(&ihost->pdev->dev,
+                        "%s: iport %p, iteration %d,"
+                        " phase %d: time_remaining %lu, bcns = %d\n",
+                        __func__, iport, iteration, phy_state,
+                        tmo, test_bit(IPORT_BCN_PENDING, &iport->flags));
+
+                res = isci_smp_get_phy_attached_dev_type(ihost, dev, phy_num,
+                                                         &attached_device_type);
+                tmo = deadline - jiffies;
+
+                if (res) {
+                        dev_warn(&ihost->pdev->dev,
+                                 "%s: iteration %d, phase %d:"
+                                 " SMP error=%d, time_remaining=%lu\n",
+                                 __func__, iteration, phy_state, res, tmo);
+                        break;
+                }
+                dev_dbg(&ihost->pdev->dev,
+                        "%s: iport %p, iteration %d,"
+                        " phase %d: time_remaining %lu, bcns = %d, "
+                        "attdevtype = %x\n",
+                        __func__, iport, iteration, phy_state,
+                        tmo, test_bit(IPORT_BCN_PENDING, &iport->flags),
+                        attached_device_type);
+
+                switch (phy_state) {
+                case SMP_PHYWAIT_PHYDOWN:
+                        /* Has the device gone away? */
+                        if (!attached_device_type)
+                                phy_state = SMP_PHYWAIT_PHYUP;
+
+                        break;
+
+                case SMP_PHYWAIT_PHYUP:
+                        /* Has the device come back? */
+                        if (attached_device_type)
+                                phy_state = SMP_PHYWAIT_DONE;
+                        break;
+
+                case SMP_PHYWAIT_DONE:
+                        break;
+                }
+
+        }
+        dev_dbg(&ihost->pdev->dev, "%s: done\n",  __func__);
+}
+
 static int isci_reset_device(struct domain_device *dev, int hard_reset)
 {
         struct isci_remote_device *idev = dev->lldd_dev;
         struct sas_phy *phy = sas_find_local_phy(dev);
         struct isci_host *ihost = dev_to_ihost(dev);
+        struct isci_port *iport = idev->isci_port;
         enum sci_status status;
         unsigned long flags;
         int rc;
@@ -1432,6 +1672,10 @@ static int isci_reset_device(struct domain_device *dev, int hard_reset)
         /* Make sure all pending requests are able to be fully terminated. */
         isci_device_clear_reset_pending(ihost, idev);
 
+        /* If this is a device on an expander, disable BCN processing. */
+        if (!scsi_is_sas_phy_local(phy))
+                set_bit(IPORT_BCN_BLOCKED, &iport->flags);
+
         rc = sas_phy_reset(phy, hard_reset);
 
         /* Terminate in-progress I/O now. */
@@ -1442,7 +1686,20 @@ static int isci_reset_device(struct domain_device *dev, int hard_reset)
         status = scic_remote_device_reset_complete(&idev->sci);
         spin_unlock_irqrestore(&ihost->scic_lock, flags);
 
-        msleep(2000); /* just like mvsas */
+        /* If this is a device on an expander, bring the phy back up. */
+        if (!scsi_is_sas_phy_local(phy)) {
+                /* A phy reset will cause the device to go away then reappear.
+                 * Since libsas will take action on incoming BCNs (eg. remove
+                 * a device going through an SMP phy-control driven reset),
+                 * we need to wait until the phy comes back up before letting
+                 * discovery proceed in libsas.
+                 */
+                isci_wait_for_smp_phy_reset(idev, phy->number);
+
+                spin_lock_irqsave(&ihost->scic_lock, flags);
+                isci_port_bcn_enable(ihost, idev->isci_port);
+                spin_unlock_irqrestore(&ihost->scic_lock, flags);
+        }
 
         if (status != SCI_SUCCESS) {
                 dev_warn(&ihost->pdev->dev,