libata-link: update hotplug to handle PMP links

Update hotplug to handle PMP links.  When PMP is attached, the PMP
number corresponds to C of SCSI H:C:I:L.  While at it, change argument
to ata_find_dev() to @devno from @id to avoid confusion with SCSI
device ID.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

2 files changed, 114 insertions, 52 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index af9c0ab600dc..14f299278f1b 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -6604,6 +6604,7 @@ int ata_host_activate(struct ata_host *host, int irq,
 void ata_port_detach(struct ata_port *ap)
 {
         unsigned long flags;
+        struct ata_link *link;
         struct ata_device *dev;
 
         if (!ap->ops->error_handler)
@@ -6621,8 +6622,10 @@ void ata_port_detach(struct ata_port *ap)
          */
         spin_lock_irqsave(ap->lock, flags);
 
-        ata_link_for_each_dev(dev, &ap->link)
-                ata_dev_disable(dev);
+        ata_port_for_each_link(link, ap) {
+                ata_link_for_each_dev(dev, link)
+                        ata_dev_disable(dev);
+        }
 
         spin_unlock_irqrestore(ap->lock, flags);
 
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 3d6d5f737994..58051ee40f1a 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -2423,21 +2423,36 @@ static unsigned int atapi_xlat(struct ata_queued_cmd *qc)
         return 0;
 }
 
-static struct ata_device * ata_find_dev(struct ata_port *ap, int id)
+static struct ata_device * ata_find_dev(struct ata_port *ap, int devno)
 {
-        if (likely(id < ata_link_max_devices(&ap->link)))
-                return &ap->link.device[id];
+        if (ap->nr_pmp_links == 0) {
+                if (likely(devno < ata_link_max_devices(&ap->link)))
+                        return &ap->link.device[devno];
+        } else {
+                if (likely(devno < ap->nr_pmp_links))
+                        return &ap->pmp_link[devno].device[0];
+        }
+
         return NULL;
 }
 
 static struct ata_device * __ata_scsi_find_dev(struct ata_port *ap,
                                         const struct scsi_device *scsidev)
 {
+        int devno;
+
         /* skip commands not addressed to targets we simulate */
-        if (unlikely(scsidev->channel || scsidev->lun))
-                return NULL;
+        if (ap->nr_pmp_links == 0) {
+                if (unlikely(scsidev->channel || scsidev->lun))
+                        return NULL;
+                devno = scsidev->id;
+        } else {
+                if (unlikely(scsidev->id || scsidev->lun))
+                        return NULL;
+                devno = scsidev->channel;
+        }
 
-        return ata_find_dev(ap, scsidev->id);
+        return ata_find_dev(ap, devno);
 }
 
 /**
@@ -2951,22 +2966,32 @@ void ata_scsi_scan_host(struct ata_port *ap, int sync)
 {
         int tries = 5;
         struct ata_device *last_failed_dev = NULL;
+        struct ata_link *link;
         struct ata_device *dev;
 
         if (ap->flags & ATA_FLAG_DISABLED)
                 return;
 
  repeat:
-        ata_link_for_each_dev(dev, &ap->link) {
-                struct scsi_device *sdev;
+        ata_port_for_each_link(link, ap) {
+                ata_link_for_each_dev(dev, link) {
+                        struct scsi_device *sdev;
+                        int channel = 0, id = 0;
 
-                if (!ata_dev_enabled(dev) || dev->sdev)
-                        continue;
+                        if (!ata_dev_enabled(dev) || dev->sdev)
+                                continue;
 
-                sdev = __scsi_add_device(ap->scsi_host, 0, dev->devno, 0, NULL);
-                if (!IS_ERR(sdev)) {
-                        dev->sdev = sdev;
-                        scsi_device_put(sdev);
+                        if (ata_is_host_link(link))
+                                id = dev->devno;
+                        else
+                                channel = link->pmp;
+
+                        sdev = __scsi_add_device(ap->scsi_host, channel, id, 0,
+                                                 NULL);
+                        if (!IS_ERR(sdev)) {
+                                dev->sdev = sdev;
+                                scsi_device_put(sdev);
+                        }
                 }
         }
 
@@ -2974,11 +2999,14 @@ void ata_scsi_scan_host(struct ata_port *ap, int sync)
          * failure occurred, scan would have failed silently.  Check
          * whether all devices are attached.
          */
-        ata_link_for_each_dev(dev, &ap->link) {
-                if (ata_dev_enabled(dev) && !dev->sdev)
-                        break;
+        ata_port_for_each_link(link, ap) {
+                ata_link_for_each_dev(dev, link) {
+                        if (ata_dev_enabled(dev) && !dev->sdev)
+                                goto exit_loop;
+                }
         }
-        if (!dev)
+ exit_loop:
+        if (!link)
                 return;
 
         /* we're missing some SCSI devices */
@@ -3092,6 +3120,25 @@ static void ata_scsi_remove_dev(struct ata_device *dev)
         }
 }
 
+static void ata_scsi_handle_link_detach(struct ata_link *link)
+{
+        struct ata_port *ap = link->ap;
+        struct ata_device *dev;
+
+        ata_link_for_each_dev(dev, link) {
+                unsigned long flags;
+
+                if (!(dev->flags & ATA_DFLAG_DETACHED))
+                        continue;
+
+                spin_lock_irqsave(ap->lock, flags);
+                dev->flags &= ~ATA_DFLAG_DETACHED;
+                spin_unlock_irqrestore(ap->lock, flags);
+
+                ata_scsi_remove_dev(dev);
+        }
+}
+
 /**
  *      ata_scsi_hotplug - SCSI part of hotplug
  *      @work: Pointer to ATA port to perform SCSI hotplug on
@@ -3108,7 +3155,7 @@ void ata_scsi_hotplug(struct work_struct *work)
 {
         struct ata_port *ap =
                 container_of(work, struct ata_port, hotplug_task.work);
-        struct ata_device *dev;
+        int i;
 
         if (ap->pflags & ATA_PFLAG_UNLOADING) {
                 DPRINTK("ENTER/EXIT - unloading\n");
@@ -3117,19 +3164,14 @@ void ata_scsi_hotplug(struct work_struct *work)
 
         DPRINTK("ENTER\n");
 
-        /* unplug detached devices */
-        ata_link_for_each_dev(dev, &ap->link) {
-                unsigned long flags;
-
-                if (!(dev->flags & ATA_DFLAG_DETACHED))
-                        continue;
-
-                spin_lock_irqsave(ap->lock, flags);
-                dev->flags &= ~ATA_DFLAG_DETACHED;
-                spin_unlock_irqrestore(ap->lock, flags);
-
-                ata_scsi_remove_dev(dev);
-        }
+        /* Unplug detached devices.  We cannot use link iterator here
+         * because PMP links have to be scanned even if PMP is
+         * currently not attached.  Iterate manually.
+         */
+        ata_scsi_handle_link_detach(&ap->link);
+        if (ap->pmp_link)
+                for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
+                        ata_scsi_handle_link_detach(&ap->pmp_link[i]);
 
         /* scan for new ones */
         ata_scsi_scan_host(ap, 0);
@@ -3157,26 +3199,40 @@ static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
                               unsigned int id, unsigned int lun)
 {
         struct ata_port *ap = ata_shost_to_port(shost);
-        struct ata_eh_info *ehi = &ap->link.eh_info;
         unsigned long flags;
-        int rc = 0;
+        int devno, rc = 0;
 
         if (!ap->ops->error_handler)
                 return -EOPNOTSUPP;
 
-        if ((channel != SCAN_WILD_CARD && channel != 0) ||
-            (lun != SCAN_WILD_CARD && lun != 0))
+        if (lun != SCAN_WILD_CARD && lun)
                 return -EINVAL;
 
+        if (ap->nr_pmp_links == 0) {
+                if (channel != SCAN_WILD_CARD && channel)
+                        return -EINVAL;
+                devno = id;
+        } else {
+                if (id != SCAN_WILD_CARD && id)
+                        return -EINVAL;
+                devno = channel;
+        }
+
         spin_lock_irqsave(ap->lock, flags);
 
-        if (id == SCAN_WILD_CARD) {
-                ehi->probe_mask |= (1 << ata_link_max_devices(&ap->link)) - 1;
-                ehi->action |= ATA_EH_SOFTRESET;
+        if (devno == SCAN_WILD_CARD) {
+                struct ata_link *link;
+
+                ata_port_for_each_link(link, ap) {
+                        struct ata_eh_info *ehi = &link->eh_info;
+                        ehi->probe_mask |= (1 << ata_link_max_devices(link)) - 1;
+                        ehi->action |= ATA_EH_SOFTRESET;
+                }
         } else {
-                struct ata_device *dev = ata_find_dev(ap, id);
+                struct ata_device *dev = ata_find_dev(ap, devno);
 
                 if (dev) {
+                        struct ata_eh_info *ehi = &dev->link->eh_info;
                         ehi->probe_mask |= 1 << dev->devno;
                         ehi->action |= ATA_EH_SOFTRESET;
                         ehi->flags |= ATA_EHI_RESUME_LINK;
@@ -3210,23 +3266,26 @@ void ata_scsi_dev_rescan(struct work_struct *work)
 {
         struct ata_port *ap =
                 container_of(work, struct ata_port, scsi_rescan_task);
+        struct ata_link *link;
         struct ata_device *dev;
         unsigned long flags;
 
         spin_lock_irqsave(ap->lock, flags);
 
-        ata_link_for_each_dev(dev, &ap->link) {
-                struct scsi_device *sdev = dev->sdev;
+        ata_port_for_each_link(link, ap) {
+                ata_link_for_each_dev(dev, link) {
+                        struct scsi_device *sdev = dev->sdev;
 
-                if (!ata_dev_enabled(dev) || !sdev)
-                        continue;
-                if (scsi_device_get(sdev))
-                        continue;
+                        if (!ata_dev_enabled(dev) || !sdev)
+                                continue;
+                        if (scsi_device_get(sdev))
+                                continue;
 
-                spin_unlock_irqrestore(ap->lock, flags);
-                scsi_rescan_device(&(sdev->sdev_gendev));
-                scsi_device_put(sdev);
-                spin_lock_irqsave(ap->lock, flags);
+                        spin_unlock_irqrestore(ap->lock, flags);
+                        scsi_rescan_device(&(sdev->sdev_gendev));
+                        scsi_device_put(sdev);
+                        spin_lock_irqsave(ap->lock, flags);
+                }
         }
 
         spin_unlock_irqrestore(ap->lock, flags);