This commit was manufactured by cvs2svn to create branch 'vserver'.
[linux-2.6.git] / drivers / scsi / libsas / sas_discover.c
diff --git a/drivers/scsi/libsas/sas_discover.c b/drivers/scsi/libsas/sas_discover.c
new file mode 100644 (file)
index 0000000..fb7df7b
--- /dev/null
@@ -0,0 +1,755 @@
+/*
+ * Serial Attached SCSI (SAS) Discover process
+ *
+ * Copyright (C) 2005 Adaptec, Inc.  All rights reserved.
+ * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
+ *
+ * This file is licensed under GPLv2.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include <linux/pci.h>
+#include <linux/scatterlist.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_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;
+
+       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)
+               kfree(scatter);
+out:
+       return res;
+}
+
+/* ---------- 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)
+{
+       unsigned long flags;
+       struct asd_sas_phy *phy;
+       struct sas_rphy *rphy;
+       struct domain_device *dev;
+
+       dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+       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);
+               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_irqrestore(&port->phy_list_lock, flags);
+
+       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 = SATA_PM;
+               else
+                       dev->dev_type = SATA_DEV;
+               dev->tproto = SATA_PROTO;
+       } else {
+               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;
+       }
+
+       sas_init_dev(dev);
+
+       switch (dev->dev_type) {
+       case SAS_END_DEV:
+               rphy = sas_end_device_alloc(port->port);
+               break;
+       case EDGE_DEV:
+               rphy = sas_expander_alloc(port->port,
+                                         SAS_EDGE_EXPANDER_DEVICE);
+               break;
+       case FANOUT_DEV:
+               rphy = sas_expander_alloc(port->port,
+                                         SAS_FANOUT_EXPANDER_DEVICE);
+               break;
+       case SATA_DEV:
+       default:
+               printk("ERROR: Unidentified device type %d\n", dev->dev_type);
+               rphy = NULL;
+               break;
+       }
+
+       if (!rphy) {
+               kfree(dev);
+               return -ENODEV;
+       }
+       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->port = port;
+       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;
+
+       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.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;
+       }
+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);
+       */
+       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;
+}
+
+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) {
+               res = i->dft->lldd_dev_found(dev);
+               if (res) {
+                       printk("sas: driver on pcidev %s cannot handle "
+                              "device %llx, error:%d\n",
+                              pci_name(sas_ha->pcidev),
+                              SAS_ADDR(dev->sas_addr), res);
+               }
+       }
+       return res;
+}
+
+
+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)
+               i->dft->lldd_dev_gone(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)
+{
+       int res;
+
+       sas_get_ata_command_set(dev);
+
+       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);
+       }
+       return res;
+}
+
+/**
+ * sas_discover_end_dev -- discover an end device (SSP, etc)
+ * @end: pointer to domain device of interest
+ *
+ * See comment in sas_discover_sata().
+ */
+int sas_discover_end_dev(struct domain_device *dev)
+{
+       int res;
+
+       res = sas_notify_lldd_dev_found(dev);
+       if (res)
+               return res;
+
+       res = sas_rphy_add(dev->rphy);
+       if (res)
+               goto out_err;
+
+       /* do this to get the end device port attributes which will have
+        * been scanned in sas_rphy_add */
+       sas_notify_lldd_dev_gone(dev);
+       sas_notify_lldd_dev_found(dev);
+
+       return 0;
+
+out_err:
+       sas_notify_lldd_dev_gone(dev);
+       return res;
+}
+
+/* ---------- Device registration and unregistration ---------- */
+
+static inline void sas_unregister_common_dev(struct domain_device *dev)
+{
+       sas_notify_lldd_dev_gone(dev);
+       if (!dev->parent)
+               dev->port->port_dev = NULL;
+       else
+               list_del_init(&dev->siblings);
+       list_del_init(&dev->dev_list_node);
+}
+
+void sas_unregister_dev(struct domain_device *dev)
+{
+       if (dev->rphy) {
+               sas_remove_children(&dev->rphy->dev);
+               sas_rphy_delete(dev->rphy);
+               dev->rphy = NULL;
+       }
+       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;
+       }
+       sas_unregister_common_dev(dev);
+}
+
+void sas_unregister_domain_devices(struct asd_sas_port *port)
+{
+       struct domain_device *dev, *n;
+
+       list_for_each_entry_safe_reverse(dev,n,&port->dev_list,dev_list_node)
+               sas_unregister_dev(dev);
+
+       port->port->rphy = NULL;
+
+}
+
+/* ---------- Discovery and Revalidation ---------- */
+
+/**
+ * sas_discover_domain -- discover the domain
+ * @port: port to the domain of interest
+ *
+ * NOTE: this process _must_ quit (return) as soon as any connection
+ * errors are encountered.  Connection recovery is done elsewhere.
+ * Discover process only interrogates devices in order to discover the
+ * domain.
+ */
+static void sas_discover_domain(struct work_struct *work)
+{
+       int error = 0;
+       struct sas_discovery_event *ev =
+               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);
+
+       if (port->port_dev)
+               return ;
+       else {
+               error = sas_get_port_device(port);
+               if (error)
+                       return;
+       }
+
+       SAS_DPRINTK("DOING DISCOVERY on port %d, pid:%d\n", port->id,
+                   current->pid);
+
+       switch (port->port_dev->dev_type) {
+       case SAS_END_DEV:
+               error = sas_discover_end_dev(port->port_dev);
+               break;
+       case EDGE_DEV:
+       case FANOUT_DEV:
+               error = sas_discover_root_expander(port->port_dev);
+               break;
+       case SATA_DEV:
+       case SATA_PM:
+               error = sas_discover_sata(port->port_dev);
+               break;
+       default:
+               SAS_DPRINTK("unhandled device %d\n", port->port_dev->dev_type);
+               break;
+       }
+
+       if (error) {
+               kfree(port->port_dev); /* not kobject_register-ed yet */
+               port->port_dev = NULL;
+       }
+
+       SAS_DPRINTK("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
+                   current->pid, error);
+}
+
+static void sas_revalidate_domain(struct work_struct *work)
+{
+       int res = 0;
+       struct sas_discovery_event *ev =
+               container_of(work, struct sas_discovery_event, work);
+       struct asd_sas_port *port = ev->port;
+
+       sas_begin_event(DISCE_REVALIDATE_DOMAIN, &port->disc.disc_event_lock,
+                       &port->disc.pending);
+
+       SAS_DPRINTK("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
+                   current->pid);
+       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);
+}
+
+/* ---------- Events ---------- */
+
+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_queue_event(ev, &disc->disc_event_lock, &disc->pending,
+                       &disc->disc_work[ev].work, port->ha->core.shost);
+
+       return 0;
+}
+
+/**
+ * sas_init_disc -- initialize the discovery struct in the port
+ * @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,
+       };
+
+       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]);
+               disc->disc_work[i].port = port;
+       }
+}