[SCSI] mptsas: support basic hotplug

Adds hotplug support for SAS end devices.  Unfortunately the fusion
firmware doesn't generate similar events for expanders addition/removal
so we can't support them yet.  Eric has an idea about a clever scheme to
find out about expander changes so that'll be added later on.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

2 files changed, 308 insertions, 31 deletions

diff --git a/drivers/message/fusion/mptbase.h b/drivers/message/fusion/mptbase.h
index 6c48d1f54ac9..af9007d498ee 100644
--- a/drivers/message/fusion/mptbase.h
+++ b/drivers/message/fusion/mptbase.h
@@ -612,6 +612,7 @@ typedef struct _MPT_ADAPTER
         struct list_head         list;
         struct net_device       *netdev;
         struct list_head         sas_topology;
+        struct mutex             sas_topology_mutex;
         MPT_SAS_MGMT             sas_mgmt;
 } MPT_ADAPTER;
 
diff --git a/drivers/message/fusion/mptsas.c b/drivers/message/fusion/mptsas.c
index 17e9757e728b..b2c682fe634f 100644
--- a/drivers/message/fusion/mptsas.c
+++ b/drivers/message/fusion/mptsas.c
@@ -5,7 +5,7 @@
  *
  *  Copyright (c) 1999-2005 LSI Logic Corporation
  *  (mailto:mpt_linux_developer@lsil.com)
- *  Copyright (c) 2005 Dell
+ *  Copyright (c) 2005-2006 Dell
  */
 /*=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*/
 /*
@@ -86,6 +86,24 @@ static int	mptsasInternalCtx = -1; /* Used only for internal commands */
 static int      mptsasMgmtCtx = -1;
 
 
+enum mptsas_hotplug_action {
+        MPTSAS_ADD_DEVICE,
+        MPTSAS_DEL_DEVICE,
+};
+
+struct mptsas_hotplug_event {
+        struct work_struct      work;
+        MPT_ADAPTER             *ioc;
+        enum mptsas_hotplug_action event_type;
+        u64                     sas_address;
+        u32                     channel;
+        u32                     id;
+        u32                     device_info;
+        u16                     handle;
+        u16                     parent_handle;
+        u8                      phy_id;
+};
+
 /*
  * SAS topology structures
  *
@@ -99,8 +117,8 @@ struct mptsas_devinfo {
         u8      phy_id;         /* phy number of parent device */
         u8      port_id;        /* sas physical port this device
                                    is assoc'd with */
-        u8      target;         /* logical target id of this device */
-        u8      bus;            /* logical bus number of this device */
+        u8      id;             /* logical target id of this device */
+        u8      channel;        /* logical bus number of this device */
         u64     sas_address;    /* WWN of this device,
                                    SATA is assigned by HBA,expander */
         u32     device_info;    /* bitfield detailed info about this device */
@@ -114,6 +132,7 @@ struct mptsas_phyinfo {
         u8      programmed_link_rate;   /* programmed max/min phy link rate */
         struct mptsas_devinfo identify; /* point to phy device info */
         struct mptsas_devinfo attached; /* point to attached device info */
+        struct sas_phy *phy;
         struct sas_rphy *rphy;
 };
 
@@ -257,24 +276,27 @@ mptsas_slave_alloc(struct scsi_device *sdev)
         }
 
         rphy = dev_to_rphy(sdev->sdev_target->dev.parent);
+        mutex_lock(&hd->ioc->sas_topology_mutex);
         list_for_each_entry(p, &hd->ioc->sas_topology, list) {
                 for (i = 0; i < p->num_phys; i++) {
                         if (p->phy_info[i].attached.sas_address ==
                                         rphy->identify.sas_address) {
                                 vdev->target_id =
-                                        p->phy_info[i].attached.target;
-                                vdev->bus_id = p->phy_info[i].attached.bus;
+                                        p->phy_info[i].attached.id;
+                                vdev->bus_id = p->phy_info[i].attached.channel;
                                 vdev->lun = sdev->lun;
                                 goto out;
                         }
                 }
         }
+        mutex_unlock(&hd->ioc->sas_topology_mutex);
 
         printk("No matching SAS device found!!\n");
         kfree(vdev);
         return -ENODEV;
 
  out:
+        mutex_unlock(&hd->ioc->sas_topology_mutex);
         vtarget->ioc_id = vdev->ioc_id;
         vtarget->target_id = vdev->target_id;
         vtarget->bus_id = vdev->bus_id;
@@ -282,6 +304,42 @@ mptsas_slave_alloc(struct scsi_device *sdev)
         return 0;
 }
 
+static void
+mptsas_slave_destroy(struct scsi_device *sdev)
+{
+        struct Scsi_Host *host = sdev->host;
+        MPT_SCSI_HOST *hd = (MPT_SCSI_HOST *)host->hostdata;
+        struct sas_rphy *rphy;
+        struct mptsas_portinfo *p;
+        int i;
+
+        /*
+         * Handle hotplug removal case.
+         * We need to clear out attached data structure.
+         */
+        rphy = dev_to_rphy(sdev->sdev_target->dev.parent);
+
+        mutex_lock(&hd->ioc->sas_topology_mutex);
+        list_for_each_entry(p, &hd->ioc->sas_topology, list) {
+                for (i = 0; i < p->num_phys; i++) {
+                        if (p->phy_info[i].attached.sas_address ==
+                                        rphy->identify.sas_address) {
+                                memset(&p->phy_info[i].attached, 0,
+                                    sizeof(struct mptsas_devinfo));
+                                p->phy_info[i].rphy = NULL;
+                                goto out;
+                        }
+                }
+        }
+
+ out:
+        mutex_unlock(&hd->ioc->sas_topology_mutex);
+        /*
+         * TODO: Issue target reset to flush firmware outstanding commands.
+         */
+        mptscsih_slave_destroy(sdev);
+}
+
 static struct scsi_host_template mptsas_driver_template = {
         .module                         = THIS_MODULE,
         .proc_name                      = "mptsas",
@@ -293,7 +351,7 @@ static struct scsi_host_template mptsas_driver_template = {
         .slave_alloc                    = mptsas_slave_alloc,
         .slave_configure                = mptscsih_slave_configure,
         .target_destroy                 = mptscsih_target_destroy,
-        .slave_destroy                  = mptscsih_slave_destroy,
+        .slave_destroy                  = mptsas_slave_destroy,
         .change_queue_depth             = mptscsih_change_queue_depth,
         .eh_abort_handler               = mptscsih_abort,
         .eh_device_reset_handler        = mptscsih_dev_reset,
@@ -649,8 +707,8 @@ mptsas_sas_device_pg0(MPT_ADAPTER *ioc, struct mptsas_devinfo *device_info,
         device_info->handle = le16_to_cpu(buffer->DevHandle);
         device_info->phy_id = buffer->PhyNum;
         device_info->port_id = buffer->PhysicalPort;
-        device_info->target = buffer->TargetID;
-        device_info->bus = buffer->Bus;
+        device_info->id = buffer->TargetID;
+        device_info->channel = buffer->Bus;
         memcpy(&sas_address, &buffer->SASAddress, sizeof(__le64));
         device_info->sas_address = le64_to_cpu(sas_address);
         device_info->device_info =
@@ -858,36 +916,36 @@ mptsas_parse_device_info(struct sas_identify *identify,
 static int mptsas_probe_one_phy(struct device *dev,
                 struct mptsas_phyinfo *phy_info, int index, int local)
 {
-        struct sas_phy *port;
+        struct sas_phy *phy;
         int error;
 
-        port = sas_phy_alloc(dev, index);
-        if (!port)
+        phy = sas_phy_alloc(dev, index);
+        if (!phy)
                 return -ENOMEM;
 
-        port->port_identifier = phy_info->port_id;
-        mptsas_parse_device_info(&port->identify, &phy_info->identify);
+        phy->port_identifier = phy_info->port_id;
+        mptsas_parse_device_info(&phy->identify, &phy_info->identify);
 
         /*
          * Set Negotiated link rate.
          */
         switch (phy_info->negotiated_link_rate) {
         case MPI_SAS_IOUNIT0_RATE_PHY_DISABLED:
-                port->negotiated_linkrate = SAS_PHY_DISABLED;
+                phy->negotiated_linkrate = SAS_PHY_DISABLED;
                 break;
         case MPI_SAS_IOUNIT0_RATE_FAILED_SPEED_NEGOTIATION:
-                port->negotiated_linkrate = SAS_LINK_RATE_FAILED;
+                phy->negotiated_linkrate = SAS_LINK_RATE_FAILED;
                 break;
         case MPI_SAS_IOUNIT0_RATE_1_5:
-                port->negotiated_linkrate = SAS_LINK_RATE_1_5_GBPS;
+                phy->negotiated_linkrate = SAS_LINK_RATE_1_5_GBPS;
                 break;
         case MPI_SAS_IOUNIT0_RATE_3_0:
-                port->negotiated_linkrate = SAS_LINK_RATE_3_0_GBPS;
+                phy->negotiated_linkrate = SAS_LINK_RATE_3_0_GBPS;
                 break;
         case MPI_SAS_IOUNIT0_RATE_SATA_OOB_COMPLETE:
         case MPI_SAS_IOUNIT0_RATE_UNKNOWN:
         default:
-                port->negotiated_linkrate = SAS_LINK_RATE_UNKNOWN;
+                phy->negotiated_linkrate = SAS_LINK_RATE_UNKNOWN;
                 break;
         }
 
@@ -896,10 +954,10 @@ static int mptsas_probe_one_phy(struct device *dev,
          */
         switch (phy_info->hw_link_rate & MPI_SAS_PHY0_PRATE_MAX_RATE_MASK) {
         case MPI_SAS_PHY0_HWRATE_MAX_RATE_1_5:
-                port->maximum_linkrate_hw = SAS_LINK_RATE_1_5_GBPS;
+                phy->maximum_linkrate_hw = SAS_LINK_RATE_1_5_GBPS;
                 break;
         case MPI_SAS_PHY0_PRATE_MAX_RATE_3_0:
-                port->maximum_linkrate_hw = SAS_LINK_RATE_3_0_GBPS;
+                phy->maximum_linkrate_hw = SAS_LINK_RATE_3_0_GBPS;
                 break;
         default:
                 break;
@@ -911,10 +969,10 @@ static int mptsas_probe_one_phy(struct device *dev,
         switch (phy_info->programmed_link_rate &
                         MPI_SAS_PHY0_PRATE_MAX_RATE_MASK) {
         case MPI_SAS_PHY0_PRATE_MAX_RATE_1_5:
-                port->maximum_linkrate = SAS_LINK_RATE_1_5_GBPS;
+                phy->maximum_linkrate = SAS_LINK_RATE_1_5_GBPS;
                 break;
         case MPI_SAS_PHY0_PRATE_MAX_RATE_3_0:
-                port->maximum_linkrate = SAS_LINK_RATE_3_0_GBPS;
+                phy->maximum_linkrate = SAS_LINK_RATE_3_0_GBPS;
                 break;
         default:
                 break;
@@ -925,10 +983,10 @@ static int mptsas_probe_one_phy(struct device *dev,
          */
         switch (phy_info->hw_link_rate & MPI_SAS_PHY0_HWRATE_MIN_RATE_MASK) {
         case MPI_SAS_PHY0_HWRATE_MIN_RATE_1_5:
-                port->minimum_linkrate_hw = SAS_LINK_RATE_1_5_GBPS;
+                phy->minimum_linkrate_hw = SAS_LINK_RATE_1_5_GBPS;
                 break;
         case MPI_SAS_PHY0_PRATE_MIN_RATE_3_0:
-                port->minimum_linkrate_hw = SAS_LINK_RATE_3_0_GBPS;
+                phy->minimum_linkrate_hw = SAS_LINK_RATE_3_0_GBPS;
                 break;
         default:
                 break;
@@ -940,28 +998,29 @@ static int mptsas_probe_one_phy(struct device *dev,
         switch (phy_info->programmed_link_rate &
                         MPI_SAS_PHY0_PRATE_MIN_RATE_MASK) {
         case MPI_SAS_PHY0_PRATE_MIN_RATE_1_5:
-                port->minimum_linkrate = SAS_LINK_RATE_1_5_GBPS;
+                phy->minimum_linkrate = SAS_LINK_RATE_1_5_GBPS;
                 break;
         case MPI_SAS_PHY0_PRATE_MIN_RATE_3_0:
-                port->minimum_linkrate = SAS_LINK_RATE_3_0_GBPS;
+                phy->minimum_linkrate = SAS_LINK_RATE_3_0_GBPS;
                 break;
         default:
                 break;
         }
 
         if (local)
-                port->local_attached = 1;
+                phy->local_attached = 1;
 
-        error = sas_phy_add(port);
+        error = sas_phy_add(phy);
         if (error) {
-                sas_phy_free(port);
+                sas_phy_free(phy);
                 return error;
         }
+        phy_info->phy = phy;
 
         if (phy_info->attached.handle) {
                 struct sas_rphy *rphy;
 
-                rphy = sas_rphy_alloc(port);
+                rphy = sas_rphy_alloc(phy);
                 if (!rphy)
                         return 0; /* non-fatal: an rphy can be added later */
 
@@ -994,7 +1053,10 @@ mptsas_probe_hba_phys(MPT_ADAPTER *ioc, int *index)
         if (error)
                 goto out_free_port_info;
 
+        mutex_lock(&ioc->sas_topology_mutex);
         list_add_tail(&port_info->list, &ioc->sas_topology);
+        mutex_unlock(&ioc->sas_topology_mutex);
+
         for (i = 0; i < port_info->num_phys; i++) {
                 mptsas_sas_phy_pg0(ioc, &port_info->phy_info[i],
                         (MPI_SAS_PHY_PGAD_FORM_PHY_NUMBER <<
@@ -1047,7 +1109,10 @@ mptsas_probe_expander_phys(MPT_ADAPTER *ioc, u32 *handle, int *index)
 
         *handle = port_info->handle;
 
+        mutex_lock(&ioc->sas_topology_mutex);
         list_add_tail(&port_info->list, &ioc->sas_topology);
+        mutex_unlock(&ioc->sas_topology_mutex);
+
         for (i = 0; i < port_info->num_phys; i++) {
                 struct device *parent;
 
@@ -1079,6 +1144,7 @@ mptsas_probe_expander_phys(MPT_ADAPTER *ioc, u32 *handle, int *index)
                  * HBA phys.
                  */
                 parent = &ioc->sh->shost_gendev;
+                mutex_lock(&ioc->sas_topology_mutex);
                 list_for_each_entry(p, &ioc->sas_topology, list) {
                         for (j = 0; j < p->num_phys; j++) {
                                 if (port_info->phy_info[i].identify.handle ==
@@ -1086,6 +1152,7 @@ mptsas_probe_expander_phys(MPT_ADAPTER *ioc, u32 *handle, int *index)
                                         parent = &p->phy_info[j].rphy->dev;
                         }
                 }
+                mutex_unlock(&ioc->sas_topology_mutex);
 
                 mptsas_probe_one_phy(parent, &port_info->phy_info[i],
                                      *index, 0);
@@ -1111,6 +1178,211 @@ mptsas_scan_sas_topology(MPT_ADAPTER *ioc)
                 ;
 }
 
+static struct mptsas_phyinfo *
+mptsas_find_phyinfo_by_parent(MPT_ADAPTER *ioc, u16 parent_handle, u8 phy_id)
+{
+        struct mptsas_portinfo *port_info;
+        struct mptsas_devinfo device_info;
+        struct mptsas_phyinfo *phy_info = NULL;
+        int i, error;
+
+        /*
+         * Retrieve the parent sas_address
+         */
+        error = mptsas_sas_device_pg0(ioc, &device_info,
+                (MPI_SAS_DEVICE_PGAD_FORM_HANDLE <<
+                 MPI_SAS_DEVICE_PGAD_FORM_SHIFT),
+                parent_handle);
+        if (error) {
+                printk("mptsas: failed to retrieve device page\n");
+                return NULL;
+        }
+
+        /*
+         * The phy_info structures are never deallocated during lifetime of
+         * a host, so the code below is safe without additional refcounting.
+         */
+        mutex_lock(&ioc->sas_topology_mutex);
+        list_for_each_entry(port_info, &ioc->sas_topology, list) {
+                for (i = 0; i < port_info->num_phys; i++) {
+                        if (port_info->phy_info[i].identify.sas_address ==
+                            device_info.sas_address &&
+                            port_info->phy_info[i].phy_id == phy_id) {
+                                phy_info = &port_info->phy_info[i];
+                                break;
+                        }
+                }
+        }
+        mutex_unlock(&ioc->sas_topology_mutex);
+
+        return phy_info;
+}
+
+static struct mptsas_phyinfo *
+mptsas_find_phyinfo_by_handle(MPT_ADAPTER *ioc, u16 handle)
+{
+        struct mptsas_portinfo *port_info;
+        struct mptsas_phyinfo *phy_info = NULL;
+        int i;
+
+        /*
+         * The phy_info structures are never deallocated during lifetime of
+         * a host, so the code below is safe without additional refcounting.
+         */
+        mutex_lock(&ioc->sas_topology_mutex);
+        list_for_each_entry(port_info, &ioc->sas_topology, list) {
+                for (i = 0; i < port_info->num_phys; i++) {
+                        if (port_info->phy_info[i].attached.handle == handle) {
+                                phy_info = &port_info->phy_info[i];
+                                break;
+                        }
+                }
+        }
+        mutex_unlock(&ioc->sas_topology_mutex);
+
+        return phy_info;
+}
+
+static void
+mptsas_hotplug_work(void *arg)
+{
+        struct mptsas_hotplug_event *ev = arg;
+        MPT_ADAPTER *ioc = ev->ioc;
+        struct mptsas_phyinfo *phy_info;
+        struct sas_rphy *rphy;
+        char *ds = NULL;
+
+        if (ev->device_info & MPI_SAS_DEVICE_INFO_SSP_TARGET)
+                ds = "ssp";
+        if (ev->device_info & MPI_SAS_DEVICE_INFO_STP_TARGET)
+                ds = "stp";
+        if (ev->device_info & MPI_SAS_DEVICE_INFO_SATA_DEVICE)
+                ds = "sata";
+
+        switch (ev->event_type) {
+        case MPTSAS_DEL_DEVICE:
+                printk(MYIOC_s_INFO_FMT
+                       "removing %s device, channel %d, id %d, phy %d\n",
+                       ioc->name, ds, ev->channel, ev->id, ev->phy_id);
+
+                phy_info = mptsas_find_phyinfo_by_handle(ioc, ev->handle);
+                if (!phy_info) {
+                        printk("mptsas: remove event for non-existant PHY.\n");
+                        break;
+                }
+
+                if (phy_info->rphy) {
+                        sas_rphy_delete(phy_info->rphy);
+                        phy_info->rphy = NULL;
+                }
+                break;
+        case MPTSAS_ADD_DEVICE:
+                printk(MYIOC_s_INFO_FMT
+                       "attaching %s device, channel %d, id %d, phy %d\n",
+                       ioc->name, ds, ev->channel, ev->id, ev->phy_id);
+
+                phy_info = mptsas_find_phyinfo_by_parent(ioc,
+                                ev->parent_handle, ev->phy_id);
+                if (!phy_info) {
+                        printk("mptsas: add event for non-existant PHY.\n");
+                        break;
+                }
+
+                if (phy_info->rphy) {
+                        printk("mptsas: trying to add existing device.\n");
+                        break;
+                }
+
+                /* fill attached info */
+                phy_info->attached.handle = ev->handle;
+                phy_info->attached.phy_id = ev->phy_id;
+                phy_info->attached.port_id = phy_info->identify.port_id;
+                phy_info->attached.id = ev->id;
+                phy_info->attached.channel = ev->channel;
+                phy_info->attached.sas_address = ev->sas_address;
+                phy_info->attached.device_info = ev->device_info;
+
+                rphy = sas_rphy_alloc(phy_info->phy);
+                if (!rphy)
+                        break; /* non-fatal: an rphy can be added later */
+
+                mptsas_parse_device_info(&rphy->identify, &phy_info->attached);
+                if (sas_rphy_add(rphy)) {
+                        sas_rphy_free(rphy);
+                        break;
+                }
+
+                phy_info->rphy = rphy;
+                break;
+        }
+
+        kfree(ev);
+}
+
+static void
+mptscsih_send_sas_event(MPT_ADAPTER *ioc,
+                EVENT_DATA_SAS_DEVICE_STATUS_CHANGE *sas_event_data)
+{
+        struct mptsas_hotplug_event *ev;
+        u32 device_info = le32_to_cpu(sas_event_data->DeviceInfo);
+        __le64 sas_address;
+
+        if ((device_info &
+             (MPI_SAS_DEVICE_INFO_SSP_TARGET |
+              MPI_SAS_DEVICE_INFO_STP_TARGET |
+              MPI_SAS_DEVICE_INFO_SATA_DEVICE )) == 0)
+                return;
+
+        if ((sas_event_data->ReasonCode &
+             (MPI_EVENT_SAS_DEV_STAT_RC_ADDED |
+              MPI_EVENT_SAS_DEV_STAT_RC_NOT_RESPONDING)) == 0)
+                return;
+
+        ev = kmalloc(sizeof(*ev), GFP_ATOMIC);
+        if (!ev) {
+                printk(KERN_WARNING "mptsas: lost hotplug event\n");
+                return;
+        }
+
+
+        INIT_WORK(&ev->work, mptsas_hotplug_work, ev);
+        ev->ioc = ioc;
+        ev->handle = le16_to_cpu(sas_event_data->DevHandle);
+        ev->parent_handle = le16_to_cpu(sas_event_data->ParentDevHandle);
+        ev->channel = sas_event_data->Bus;
+        ev->id = sas_event_data->TargetID;
+        ev->phy_id = sas_event_data->PhyNum;
+        memcpy(&sas_address, &sas_event_data->SASAddress, sizeof(__le64));
+        ev->sas_address = le64_to_cpu(sas_address);
+        ev->device_info = device_info;
+
+        if (sas_event_data->ReasonCode & MPI_EVENT_SAS_DEV_STAT_RC_ADDED)
+                ev->event_type = MPTSAS_ADD_DEVICE;
+        else
+                ev->event_type = MPTSAS_DEL_DEVICE;
+
+        schedule_work(&ev->work);
+}
+
+static int
+mptsas_event_process(MPT_ADAPTER *ioc, EventNotificationReply_t *reply)
+{
+        u8 event = le32_to_cpu(reply->Event) & 0xFF;
+
+        if (!ioc->sh)
+                return 1;
+
+        switch (event) {
+        case MPI_EVENT_SAS_DEVICE_STATUS_CHANGE:
+                mptscsih_send_sas_event(ioc,
+                        (EVENT_DATA_SAS_DEVICE_STATUS_CHANGE *)reply->Data);
+                return 1;               /* currently means nothing really */
+
+        default:
+                return mptscsih_event_process(ioc, reply);
+        }
+}
+
 static int
 mptsas_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
@@ -1203,6 +1475,8 @@ mptsas_probe(struct pci_dev *pdev, const struct pci_device_id *id)
         sh->unique_id = ioc->id;
 
         INIT_LIST_HEAD(&ioc->sas_topology);
+        mutex_init(&ioc->sas_topology_mutex);
+
         init_MUTEX(&ioc->sas_mgmt.mutex);
         init_completion(&ioc->sas_mgmt.done);
 
@@ -1339,10 +1613,12 @@ static void __devexit mptsas_remove(struct pci_dev *pdev)
 
         sas_remove_host(ioc->sh);
 
+        mutex_lock(&ioc->sas_topology_mutex);
         list_for_each_entry_safe(p, n, &ioc->sas_topology, list) {
                 list_del(&p->list);
                 kfree(p);
         }
+        mutex_unlock(&ioc->sas_topology_mutex);
 
         mptscsih_remove(pdev);
 }
@@ -1393,7 +1669,7 @@ mptsas_init(void)
                 mpt_register(mptscsih_scandv_complete, MPTSAS_DRIVER);
         mptsasMgmtCtx = mpt_register(mptsas_mgmt_done, MPTSAS_DRIVER);
 
-        if (mpt_event_register(mptsasDoneCtx, mptscsih_event_process) == 0) {
+        if (mpt_event_register(mptsasDoneCtx, mptsas_event_process) == 0) {
                 devtprintk((KERN_INFO MYNAM
                   ": Registered for IOC event notifications\n"));
         }