[SCSI] libsas: restore scan order
[linux-2.6.git] / drivers / scsi / libsas / sas_discover.c
index 4d768db..18fa364 100644 (file)
  *
  */
 
-#include <linux/pci.h>
 #include <linux/scatterlist.h>
+#include <linux/slab.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)
 {
-        INIT_LIST_HEAD(&dev->siblings);
-        INIT_LIST_HEAD(&dev->dev_list_node);
-        switch (dev->dev_type) {
-        case SAS_END_DEV:
-                break;
-        case EDGE_DEV:
-        case FANOUT_DEV:
-                INIT_LIST_HEAD(&dev->ex_dev.children);
-                break;
-        case SATA_DEV:
-        case SATA_PM:
-        case SATA_PM_PORT:
-                INIT_LIST_HEAD(&dev->sata_dev.children);
-                break;
-        default:
-                break;
-        }
-}
-
-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
- * @pci_dma_dir: PCI_DMA_...
- */
-static int sas_execute_task(struct sas_task *task, void *buffer, int size,
-                           int pci_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 (pci_dma_dir != PCI_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 = pci_dma_dir;
-       task->task_done = sas_disc_task_done;
-       if (pci_dma_dir != PCI_DMA_NONE &&
-           sas_protocol_ata(task->task_proto)) {
-               task->num_scatter = pci_map_sg(task->dev->port->ha->pcidev,
-                                              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 = -ETASK;
-               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_BUSY ||
-                          task->task_status.stat == SAM_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_CHECK_COND) {
-                       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_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 (pci_dma_dir != PCI_DMA_NONE) {
-               if (sas_protocol_ata(task->task_proto))
-                       pci_unmap_sg(task->dev->port->ha->pcidev,
-                                    task->scatter, task->num_scatter,
-                                    task->data_dir);
-               kfree(scatter);
+       switch (dev->dev_type) {
+       case SAS_END_DEV:
+               break;
+       case EDGE_DEV:
+       case FANOUT_DEV:
+               INIT_LIST_HEAD(&dev->ex_dev.children);
+               mutex_init(&dev->ex_dev.cmd_mutex);
+               break;
+       case SATA_DEV:
+       case SATA_PM:
+       case SATA_PM_PORT:
+       case SATA_PENDING:
+               INIT_LIST_HEAD(&dev->sata_dev.children);
+               break;
+       default:
+               break;
        }
-out:
-       return res;
 }
 
 /* ---------- Domain device discovery ---------- */
@@ -228,14 +74,14 @@ static int sas_get_port_device(struct asd_sas_port *port)
        struct sas_rphy *rphy;
        struct domain_device *dev;
 
-       dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+       dev = sas_alloc_device();
        if (!dev)
                return -ENOMEM;
 
        spin_lock_irqsave(&port->phy_list_lock, flags);
        if (list_empty(&port->phy_list)) {
                spin_unlock_irqrestore(&port->phy_list_lock, flags);
-               kfree(dev);
+               sas_put_device(dev);
                return -ENODEV;
        }
        phy = container_of(port->phy_list.next, struct asd_sas_phy, port_phy_el);
@@ -254,7 +100,7 @@ static int sas_get_port_device(struct asd_sas_port *port)
                        dev->dev_type = SATA_PM;
                else
                        dev->dev_type = SATA_DEV;
-               dev->tproto = SATA_PROTO;
+               dev->tproto = SAS_PROTOCOL_SATA;
        } else {
                struct sas_identify_frame *id =
                        (struct sas_identify_frame *) dev->frame_rcvd;
@@ -285,7 +131,7 @@ static int sas_get_port_device(struct asd_sas_port *port)
        }
 
        if (!rphy) {
-               kfree(dev);
+               sas_put_device(dev);
                return -ENODEV;
        }
        rphy->identify.phy_identifier = phy->phy->identify.phy_identifier;
@@ -302,212 +148,22 @@ static int sas_get_port_device(struct asd_sas_port *port)
        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;
-       spin_lock(&port->dev_list_lock);
-       list_add_tail(&dev->dev_list_node, &port->dev_list);
-       spin_unlock(&port->dev_list_lock);
 
-       return 0;
-}
-
-/* ---------- Discover and Revalidate ---------- */
-
-/* ---------- 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 ((fis->sector_count == 1 && /* ATA */
-            fis->lbal         == 1 &&
-            fis->lbam         == 0 &&
-            fis->lbah         == 0 &&
-            fis->device       == 0)
-           ||
-           (fis->sector_count == 0 && /* CE-ATA (mATA) */
-            fis->lbal         == 0 &&
-            fis->lbam         == 0xCE &&
-            fis->lbah         == 0xAA &&
-            (fis->device & ~0x10) == 0))
-
-               dev->sata_dev.command_set = ATA_COMMAND_SET;
-
-       else if ((fis->interrupt_reason == 1 && /* ATAPI */
-                 fis->lbal             == 1 &&
-                 fis->byte_count_low   == 0x14 &&
-                 fis->byte_count_high  == 0xEB &&
-                 (fis->device & ~0x10) == 0))
-
-               dev->sata_dev.command_set = ATAPI_COMMAND_SET;
-
-       else if ((fis->sector_count == 1 && /* SEMB */
-                 fis->lbal         == 1 &&
-                 fis->lbam         == 0x3C &&
-                 fis->lbah         == 0xC3 &&
-                 fis->device       == 0)
-               ||
-                (fis->interrupt_reason == 1 && /* SATA PM */
-                 fis->lbal             == 1 &&
-                 fis->byte_count_low   == 0x69 &&
-                 fis->byte_count_high  == 0x96 &&
-                 (fis->device & ~0x10) == 0))
-
-               /* Treat it as a superset? */
-               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
- * @pci_dma_dir: PCI_DMA_...
- */
-static int sas_issue_ata_cmd(struct domain_device *dev, u8 command,
-                            u8 features, void *buffer, int size,
-                            int pci_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, pci_dma_dir);
-
-       sas_free_task(task);
-out:
-       return res;
-}
-
-static void sas_sata_propagate_sas_addr(struct domain_device *dev)
-{
-       unsigned long flags;
-       struct asd_sas_port *port = dev->port;
-       struct asd_sas_phy  *phy;
-
-       BUG_ON(dev->parent);
-
-       memcpy(port->attached_sas_addr, dev->sas_addr, SAS_ADDR_SIZE);
-       spin_lock_irqsave(&port->phy_list_lock, flags);
-       list_for_each_entry(phy, &port->phy_list, port_phy_el)
-               memcpy(phy->attached_sas_addr, dev->sas_addr, SAS_ADDR_SIZE);
-       spin_unlock_irqrestore(&port->phy_list_lock, flags);
-}
-
-#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)
-{
-       int     res;
-       __le16  *identify_x;
-       u8      command;
-
-       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;
-       }
-
-       res = sas_issue_ata_cmd(dev, command, 0, identify_x, 512,
-                               PCI_DMA_FROMDEVICE);
-       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 (!le16_to_cpu(identify_x[83] & (1<<6)))
-                       goto cont1;
-               res = sas_issue_ata_cmd(dev, ATA_SET_FEATURES,
-                                       ATA_FEATURE_PUP_STBY_SPIN_UP,
-                                       NULL, 0, PCI_DMA_NONE);
-               if (res)
-                       goto cont1;
-
-               schedule_timeout_interruptible(5*HZ); /* More time? */
-               res = sas_issue_ata_cmd(dev, command, 0, identify_x, 512,
-                                       PCI_DMA_FROMDEVICE);
-               if (res)
-                       goto out_err;
+       if (dev_is_sata(dev) || dev->dev_type == SAS_END_DEV)
+               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);
        }
-cont1:
-       /* Get WWN */
-       if (dev->port->oob_mode != SATA_OOB_MODE) {
-               memcpy(dev->sas_addr, dev->sata_dev.rps_resp.rps.stp_sas_addr,
-                      SAS_ADDR_SIZE);
-       } else if (dev->sata_dev.command_set == ATA_COMMAND_SET &&
-                  (le16_to_cpu(dev->sata_dev.identify_device[108]) & 0xF000)
-                  == 0x5000) {
-               int i;
-
-               for (i = 0; i < 4; i++) {
-                       dev->sas_addr[2*i] =
-            (le16_to_cpu(dev->sata_dev.identify_device[108+i]) & 0xFF00) >> 8;
-                       dev->sas_addr[2*i+1] =
-             le16_to_cpu(dev->sata_dev.identify_device[108+i]) & 0x00FF;
-               }
-       }
-       sas_hash_addr(dev->hashed_sas_addr, dev->sas_addr);
-       if (!dev->parent)
-               sas_sata_propagate_sas_addr(dev);
-
-       /* XXX Hint: register this SATA device with SATL.
-          When this returns, dev->sata_dev->lu is alive and
-          present.
-       sas_satl_register_dev(dev);
-       */
-
-       sas_fill_in_rphy(dev, dev->rphy);
 
        return 0;
-out_err:
-       dev->sata_dev.identify_packet_device = NULL;
-       dev->sata_dev.identify_device = NULL;
-       kfree(identify_x);
-       return res;
 }
 
-static int sas_discover_sata_pm(struct domain_device *dev)
-{
-       return -ENODEV;
-}
+/* ---------- Discover and Revalidate ---------- */
 
 int sas_notify_lldd_dev_found(struct domain_device *dev)
 {
@@ -521,9 +177,10 @@ int sas_notify_lldd_dev_found(struct domain_device *dev)
                if (res) {
                        printk("sas: driver on pcidev %s cannot handle "
                               "device %llx, error:%d\n",
-                              pci_name(sas_ha->pcidev),
+                              dev_name(sas_ha->dev),
                               SAS_ADDR(dev->sas_addr), res);
                }
+               kref_get(&dev->kref);
        }
        return res;
 }
@@ -535,54 +192,39 @@ void sas_notify_lldd_dev_gone(struct domain_device *dev)
        struct Scsi_Host *shost = sas_ha->core.shost;
        struct sas_internal *i = to_sas_internal(shost->transportt);
 
-       if (i->dft->lldd_dev_gone)
+       if (i->dft->lldd_dev_gone) {
                i->dft->lldd_dev_gone(dev);
+               sas_put_device(dev);
+       }
 }
 
-/* ---------- Common/dispatchers ---------- */
-
-/**
- * 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.
- */
-int sas_discover_sata(struct domain_device *dev)
+static void sas_probe_devices(struct work_struct *work)
 {
-       int res;
+       struct domain_device *dev, *n;
+       struct sas_discovery_event *ev =
+               container_of(work, struct sas_discovery_event, work);
+       struct asd_sas_port *port = ev->port;
 
-       sas_get_ata_command_set(dev);
+       clear_bit(DISCE_PROBE, &port->disc.pending);
 
-       res = sas_notify_lldd_dev_found(dev);
-       if (res)
-               return res;
+       list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node) {
+               int err;
 
-       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);
-       }
+               spin_lock_irq(&port->dev_list_lock);
+               list_add_tail(&dev->dev_list_node, &port->dev_list);
+               spin_unlock_irq(&port->dev_list_lock);
 
-       return res;
+               err = sas_rphy_add(dev->rphy);
+
+               if (err) {
+                       SAS_DPRINTK("%s: for %s device %16llx returned %d\n",
+                                   __func__, dev->parent ? "exp-attached" :
+                                                           "direct-attached",
+                                   SAS_ADDR(dev->sas_addr), err);
+                       sas_unregister_dev(port, dev);
+               } else
+                       list_del_init(&dev->disco_list_node);
+       }
 }
 
 /**
@@ -597,58 +239,125 @@ int sas_discover_end_dev(struct domain_device *dev)
 
        res = sas_notify_lldd_dev_found(dev);
        if (res)
-               goto out_err2;
-
-       res = sas_rphy_add(dev->rphy);
-       if (res)
-               goto out_err;
+               return res;
+       sas_discover_event(dev->port, DISCE_PROBE);
 
        return 0;
-
-out_err:
-       sas_notify_lldd_dev_gone(dev);
-out_err2:
-       return res;
 }
 
 /* ---------- Device registration and unregistration ---------- */
 
-static inline void sas_unregister_common_dev(struct domain_device *dev)
+void sas_free_device(struct kref *kref)
+{
+       struct domain_device *dev = container_of(kref, typeof(*dev), kref);
+
+       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->dev_type == EDGE_DEV || dev->dev_type == FANOUT_DEV)
+               kfree(dev->ex_dev.ex_phy);
+
+       if (dev_is_sata(dev) && dev->sata_dev.ap) {
+               ata_sas_port_destroy(dev->sata_dev.ap);
+               dev->sata_dev.ap = NULL;
+       }
+
+       kfree(dev);
+}
+
+static void sas_unregister_common_dev(struct asd_sas_port *port, struct domain_device *dev)
 {
        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);
+       spin_unlock_irq(&port->dev_list_lock);
+
+       sas_put_device(dev);
 }
 
-void sas_unregister_dev(struct domain_device *dev)
+static void sas_destruct_devices(struct work_struct *work)
 {
-       if (dev->rphy) {
+       struct domain_device *dev, *n;
+       struct sas_discovery_event *ev =
+               container_of(work, struct sas_discovery_event, work);
+       struct asd_sas_port *port = ev->port;
+
+       clear_bit(DISCE_DESTRUCT, &port->disc.pending);
+
+       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);
                dev->rphy = NULL;
+               sas_unregister_common_dev(port, dev);
        }
-       if (dev->dev_type == EDGE_DEV || dev->dev_type == FANOUT_DEV) {
-               /* remove the phys and ports, everything else should be gone */
-               kfree(dev->ex_dev.ex_phy);
-               dev->ex_dev.ex_phy = NULL;
+}
+
+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);
+               dev->rphy = NULL;
+               sas_unregister_common_dev(port, dev);
+       }
+
+       if (dev->rphy && !test_and_set_bit(SAS_DEV_DESTROY, &dev->state)) {
+               sas_rphy_unlink(dev->rphy);
+               list_move_tail(&dev->disco_list_node, &port->destroy_list);
+               sas_discover_event(dev->port, DISCE_DESTRUCT);
        }
-       sas_unregister_common_dev(dev);
 }
 
-void sas_unregister_domain_devices(struct asd_sas_port *port)
+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)
-               sas_unregister_dev(dev);
+       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 ---------- */
 
 /**
@@ -668,8 +377,7 @@ static void sas_discover_domain(struct work_struct *work)
                container_of(work, struct sas_discovery_event, work);
        struct asd_sas_port *port = ev->port;
 
-       sas_begin_event(DISCE_DISCOVER_DOMAIN, &port->disc.disc_event_lock,
-                       &port->disc.pending);
+       clear_bit(DISCE_DISCOVER_DOMAIN, &port->disc.pending);
 
        if (port->port_dev)
                return;
@@ -680,7 +388,7 @@ static void sas_discover_domain(struct work_struct *work)
        dev = port->port_dev;
 
        SAS_DPRINTK("DOING DISCOVERY on port %d, pid:%d\n", port->id,
-                   current->pid);
+                   task_pid_nr(current));
 
        switch (dev->dev_type) {
        case SAS_END_DEV:
@@ -692,9 +400,15 @@ static void sas_discover_domain(struct work_struct *work)
                break;
        case SATA_DEV:
        case SATA_PM:
+#ifdef CONFIG_SCSI_SAS_ATA
                error = sas_discover_sata(dev);
                break;
+#else
+               SAS_DPRINTK("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
+               /* Fall through */
+#endif
        default:
+               error = -ENXIO;
                SAS_DPRINTK("unhandled device %d\n", dev->dev_type);
                break;
        }
@@ -703,16 +417,17 @@ static void sas_discover_domain(struct work_struct *work)
                sas_rphy_free(dev->rphy);
                dev->rphy = NULL;
 
-               spin_lock(&port->dev_list_lock);
+               list_del_init(&dev->disco_list_node);
+               spin_lock_irq(&port->dev_list_lock);
                list_del_init(&dev->dev_list_node);
-               spin_unlock(&port->dev_list_lock);
+               spin_unlock_irq(&port->dev_list_lock);
 
-               kfree(dev); /* not kobject_register-ed yet */
+               sas_put_device(dev);
                port->port_dev = NULL;
        }
 
        SAS_DPRINTK("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
-                   current->pid, error);
+                   task_pid_nr(current), error);
 }
 
 static void sas_revalidate_domain(struct work_struct *work)
@@ -721,21 +436,51 @@ static void sas_revalidate_domain(struct work_struct *work)
        struct sas_discovery_event *ev =
                container_of(work, struct sas_discovery_event, work);
        struct asd_sas_port *port = ev->port;
+       struct sas_ha_struct *ha = port->ha;
 
-       sas_begin_event(DISCE_REVALIDATE_DOMAIN, &port->disc.disc_event_lock,
-                       &port->disc.pending);
+       /* prevent revalidation from finding sata links in recovery */
+       mutex_lock(&ha->disco_mutex);
+       if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
+               SAS_DPRINTK("REVALIDATION DEFERRED on port %d, pid:%d\n",
+                           port->id, task_pid_nr(current));
+               goto out;
+       }
+
+       clear_bit(DISCE_REVALIDATE_DOMAIN, &port->disc.pending);
 
        SAS_DPRINTK("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
-                   current->pid);
+                   task_pid_nr(current));
+
        if (port->port_dev)
                res = sas_ex_revalidate_domain(port->port_dev);
 
        SAS_DPRINTK("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
-                   port->id, current->pid, res);
+                   port->id, task_pid_nr(current), res);
+ out:
+       mutex_unlock(&ha->disco_mutex);
 }
 
 /* ---------- Events ---------- */
 
+static void sas_chain_work(struct sas_ha_struct *ha, struct work_struct *work)
+{
+       /* chained work is not subject to SA_HA_DRAINING or SAS_HA_REGISTERED */
+       scsi_queue_work(ha->core.shost, work);
+}
+
+static void sas_chain_event(int event, unsigned long *pending,
+                           struct work_struct *work,
+                           struct sas_ha_struct *ha)
+{
+       if (!test_and_set_bit(event, pending)) {
+               unsigned long flags;
+
+               spin_lock_irqsave(&ha->state_lock, flags);
+               sas_chain_work(ha, work);
+               spin_unlock_irqrestore(&ha->state_lock, flags);
+       }
+}
+
 int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
 {
        struct sas_discovery *disc;
@@ -746,8 +491,7 @@ int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
 
        BUG_ON(ev >= DISC_NUM_EVENTS);
 
-       sas_queue_event(ev, &disc->disc_event_lock, &disc->pending,
-                       &disc->disc_work[ev].work, port->ha);
+       sas_chain_event(ev, &disc->pending, &disc->disc_work[ev].work, port->ha);
 
        return 0;
 }
@@ -765,9 +509,10 @@ void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port)
        static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
                [DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
                [DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
+               [DISCE_PROBE] = sas_probe_devices,
+               [DISCE_DESTRUCT] = sas_destruct_devices,
        };
 
-       spin_lock_init(&disc->disc_event_lock);
        disc->pending = 0;
        for (i = 0; i < DISC_NUM_EVENTS; i++) {
                INIT_WORK(&disc->disc_work[i].work, sas_event_fns[i]);