[PATCH] libata-hp: update unload-unplug

Update unload unplug - driver unloading / PCI removal.  This is done
by ata_port_detach() which short-circuits EH, disables all devices and
freezes the port.  With this patch, EH and unloading/unplugging are
properly synchronized.

Signed-off-by: Tejun Heo <htejun@gmail.com>

diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index afb3805f9e95eac8a206845b207d47c7f3d08939..60f455bf3696b1f83b3aa554919fb0c5cad9b10d 100644 (file)
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -1389,21 +1389,17 @@ static void ahci_remove_one (struct pci_dev *pdev)
        struct device *dev = pci_dev_to_dev(pdev);
        struct ata_host_set *host_set = dev_get_drvdata(dev);
        struct ahci_host_priv *hpriv = host_set->private_data;
-       struct ata_port *ap;
        unsigned int i;
        int have_msi;
 
-       for (i = 0; i < host_set->n_ports; i++) {
-               ap = host_set->ports[i];
-
-               scsi_remove_host(ap->host);
-       }
+       for (i = 0; i < host_set->n_ports; i++)
+               ata_port_detach(host_set->ports[i]);
 
        have_msi = hpriv->flags & AHCI_FLAG_MSI;
        free_irq(host_set->irq, host_set);
 
        for (i = 0; i < host_set->n_ports; i++) {
-               ap = host_set->ports[i];
+               struct ata_port *ap = host_set->ports[i];
 
                ata_scsi_release(ap->host);
                scsi_host_put(ap->host);

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index a42877e6b8655a3e943792e03654863c3d62e1e6..01f2c59536bcb2060740b4eef8b322232e9e4607 100644 (file)
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -5609,6 +5609,63 @@ err_free_ret:
        return 0;
 }
 
+/**
+ *     ata_port_detach - Detach ATA port in prepration of device removal
+ *     @ap: ATA port to be detached
+ *
+ *     Detach all ATA devices and the associated SCSI devices of @ap;
+ *     then, remove the associated SCSI host.  @ap is guaranteed to
+ *     be quiescent on return from this function.
+ *
+ *     LOCKING:
+ *     Kernel thread context (may sleep).
+ */
+void ata_port_detach(struct ata_port *ap)
+{
+       unsigned long flags;
+       int i;
+
+       if (!ap->ops->error_handler)
+               return;
+
+       /* tell EH we're leaving & flush EH */
+       spin_lock_irqsave(&ap->host_set->lock, flags);
+       ap->flags |= ATA_FLAG_UNLOADING;
+       spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+       ata_port_wait_eh(ap);
+
+       /* EH is now guaranteed to see UNLOADING, so no new device
+        * will be attached.  Disable all existing devices.
+        */
+       spin_lock_irqsave(&ap->host_set->lock, flags);
+
+       for (i = 0; i < ATA_MAX_DEVICES; i++)
+               ata_dev_disable(&ap->device[i]);
+
+       spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+       /* Final freeze & EH.  All in-flight commands are aborted.  EH
+        * will be skipped and retrials will be terminated with bad
+        * target.
+        */
+       spin_lock_irqsave(&ap->host_set->lock, flags);
+       ata_port_freeze(ap);    /* won't be thawed */
+       spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+       ata_port_wait_eh(ap);
+
+       /* Flush hotplug task.  The sequence is similar to
+        * ata_port_flush_task().
+        */
+       flush_workqueue(ata_aux_wq);
+       cancel_delayed_work(&ap->hotplug_task);
+       flush_workqueue(ata_aux_wq);
+
+       /* remove the associated SCSI host */
+       scsi_remove_host(ap->host);
+}
+
 /**
  *     ata_host_set_remove - PCI layer callback for device removal
  *     @host_set: ATA host set that was removed
@@ -5622,18 +5679,15 @@ err_free_ret:
 
 void ata_host_set_remove(struct ata_host_set *host_set)
 {
-       struct ata_port *ap;
        unsigned int i;
 
-       for (i = 0; i < host_set->n_ports; i++) {
-               ap = host_set->ports[i];
-               scsi_remove_host(ap->host);
-       }
+       for (i = 0; i < host_set->n_ports; i++)
+               ata_port_detach(host_set->ports[i]);
 
        free_irq(host_set->irq, host_set);
 
        for (i = 0; i < host_set->n_ports; i++) {
-               ap = host_set->ports[i];
+               struct ata_port *ap = host_set->ports[i];
 
                ata_scsi_release(ap->host);
 
@@ -5901,6 +5955,7 @@ EXPORT_SYMBOL_GPL(sata_deb_timing_before_fsrst);
 EXPORT_SYMBOL_GPL(ata_std_bios_param);
 EXPORT_SYMBOL_GPL(ata_std_ports);
 EXPORT_SYMBOL_GPL(ata_device_add);
+EXPORT_SYMBOL_GPL(ata_port_detach);
 EXPORT_SYMBOL_GPL(ata_host_set_remove);
 EXPORT_SYMBOL_GPL(ata_sg_init);
 EXPORT_SYMBOL_GPL(ata_sg_init_one);

diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c
index 70c132bef68e8a5d76b3d54f679a44b2a0d22d13..30a83a57a12f2d6a0ffb88f951004f9d5711bb96 100644 (file)
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -46,6 +46,7 @@
 #include "libata.h"
 
 static void __ata_port_freeze(struct ata_port *ap);
+static void ata_eh_finish(struct ata_port *ap);
 
 static void ata_ering_record(struct ata_ering *ering, int is_io,
                             unsigned int err_mask)
@@ -242,8 +243,11 @@ void ata_scsi_error(struct Scsi_Host *host)
 
                spin_unlock_irqrestore(hs_lock, flags);
 
-               /* invoke EH */
-               ap->ops->error_handler(ap);
+               /* invoke EH.  if unloading, just finish failed qcs */
+               if (!(ap->flags & ATA_FLAG_UNLOADING))
+                       ap->ops->error_handler(ap);
+               else
+                       ata_eh_finish(ap);
 
                /* Exception might have happend after ->error_handler
                 * recovered the port but before this point.  Repeat

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 74786c33c52659b4c28f7f9475dcaf2547417e0a..f11ba2715bef7916ad26e1071dcf588ab40bc329 100644 (file)
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -649,6 +649,7 @@ extern int ata_pci_device_resume(struct pci_dev *pdev);
 extern int ata_pci_clear_simplex(struct pci_dev *pdev);
 #endif /* CONFIG_PCI */
 extern int ata_device_add(const struct ata_probe_ent *ent);
+extern void ata_port_detach(struct ata_port *ap);
 extern void ata_host_set_remove(struct ata_host_set *host_set);
 extern int ata_scsi_detect(struct scsi_host_template *sht);
 extern int ata_scsi_ioctl(struct scsi_device *dev, int cmd, void __user *arg);