[SCSI] correct transport class abstraction to work outside SCSI

I recently tried to construct a totally generic transport class and
found there were certain features missing from the current abstract
transport class.  Most notable is that you have to hang the data on the
class_device but most of the API is framed in terms of the generic
device, not the class_device.

These changes are two fold

- Provide the class_device to all of the setup and configure APIs
- Provide and extra API to take the device and the attribute class and
  return the corresponding class_device

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

6 files changed, 72 insertions, 20 deletions

diff --git a/drivers/base/attribute_container.c b/drivers/base/attribute_container.c
index ec615d854be9..62c093db11e6 100644
--- a/drivers/base/attribute_container.c
+++ b/drivers/base/attribute_container.c
@@ -58,6 +58,7 @@ attribute_container_register(struct attribute_container *cont)
 {
         INIT_LIST_HEAD(&cont->node);
         INIT_LIST_HEAD(&cont->containers);
+        spin_lock_init(&cont->containers_lock);
                 
         down(&attribute_container_mutex);
         list_add_tail(&cont->node, &attribute_container_list);
@@ -77,11 +78,13 @@ attribute_container_unregister(struct attribute_container *cont)
 {
         int retval = -EBUSY;
         down(&attribute_container_mutex);
+        spin_lock(&cont->containers_lock);
         if (!list_empty(&cont->containers))
                 goto out;
         retval = 0;
         list_del(&cont->node);
  out:
+        spin_unlock(&cont->containers_lock);
         up(&attribute_container_mutex);
         return retval;
                 
@@ -151,7 +154,9 @@ attribute_container_add_device(struct device *dev,
                         fn(cont, dev, &ic->classdev);
                 else
                         attribute_container_add_class_device(&ic->classdev);
+                spin_lock(&cont->containers_lock);
                 list_add_tail(&ic->node, &cont->containers);
+                spin_unlock(&cont->containers_lock);
         }
         up(&attribute_container_mutex);
 }
@@ -189,6 +194,7 @@ attribute_container_remove_device(struct device *dev,
 
                 if (!cont->match(cont, dev))
                         continue;
+                spin_lock(&cont->containers_lock);
                 list_for_each_entry_safe(ic, tmp, &cont->containers, node) {
                         if (dev != ic->classdev.dev)
                                 continue;
@@ -200,6 +206,7 @@ attribute_container_remove_device(struct device *dev,
                                 class_device_unregister(&ic->classdev);
                         }
                 }
+                spin_unlock(&cont->containers_lock);
         }
         up(&attribute_container_mutex);
 }
@@ -230,10 +237,12 @@ attribute_container_device_trigger(struct device *dev,
                 if (!cont->match(cont, dev))
                         continue;
 
+                spin_lock(&cont->containers_lock);
                 list_for_each_entry_safe(ic, tmp, &cont->containers, node) {
                         if (dev == ic->classdev.dev)
                                 fn(cont, dev, &ic->classdev);
                 }
+                spin_unlock(&cont->containers_lock);
         }
         up(&attribute_container_mutex);
 }
@@ -368,6 +377,35 @@ attribute_container_class_device_del(struct class_device *classdev)
 }
 EXPORT_SYMBOL_GPL(attribute_container_class_device_del);
 
+/**
+ * attribute_container_find_class_device - find the corresponding class_device
+ *
+ * @cont:       the container
+ * @dev:        the generic device
+ *
+ * Looks up the device in the container's list of class devices and returns
+ * the corresponding class_device.
+ */
+struct class_device *
+attribute_container_find_class_device(struct attribute_container *cont,
+                                      struct device *dev)
+{
+        struct class_device *cdev = NULL;
+        struct internal_container *ic;
+
+        spin_lock(&cont->containers_lock);
+        list_for_each_entry(ic, &cont->containers, node) {
+                if (ic->classdev.dev == dev) {
+                        cdev = &ic->classdev;
+                        break;
+                }
+        }
+        spin_unlock(&cont->containers_lock);
+
+        return cdev;
+}
+EXPORT_SYMBOL_GPL(attribute_container_find_class_device);
+
 int __init
 attribute_container_init(void)
 {
diff --git a/drivers/base/transport_class.c b/drivers/base/transport_class.c
index 6c2b447a3336..4fb4c5de8470 100644
--- a/drivers/base/transport_class.c
+++ b/drivers/base/transport_class.c
@@ -64,7 +64,9 @@ void transport_class_unregister(struct transport_class *tclass)
 }
 EXPORT_SYMBOL_GPL(transport_class_unregister);
 
-static int anon_transport_dummy_function(struct device *dev)
+static int anon_transport_dummy_function(struct transport_container *tc,
+                                         struct device *dev,
+                                         struct class_device *cdev)
 {
         /* do nothing */
         return 0;
@@ -115,9 +117,10 @@ static int transport_setup_classdev(struct attribute_container *cont,
                                     struct class_device *classdev)
 {
         struct transport_class *tclass = class_to_transport_class(cont->class);
+        struct transport_container *tcont = attribute_container_to_transport_container(cont);
 
         if (tclass->setup)
-                tclass->setup(dev);
+                tclass->setup(tcont, dev, classdev);
 
         return 0;
 }
@@ -178,12 +181,14 @@ void transport_add_device(struct device *dev)
 EXPORT_SYMBOL_GPL(transport_add_device);
 
 static int transport_configure(struct attribute_container *cont,
-                               struct device *dev)
+                               struct device *dev,
+                               struct class_device *cdev)
 {
         struct transport_class *tclass = class_to_transport_class(cont->class);
+        struct transport_container *tcont = attribute_container_to_transport_container(cont);
 
         if (tclass->configure)
-                tclass->configure(dev);
+                tclass->configure(tcont, dev, cdev);
 
         return 0;
 }
@@ -202,7 +207,7 @@ static int transport_configure(struct attribute_container *cont,
  */
 void transport_configure_device(struct device *dev)
 {
-        attribute_container_trigger(dev, transport_configure);
+        attribute_container_device_trigger(dev, transport_configure);
 }
 EXPORT_SYMBOL_GPL(transport_configure_device);
 
@@ -215,7 +220,7 @@ static int transport_remove_classdev(struct attribute_container *cont,
         struct transport_class *tclass = class_to_transport_class(cont->class);
 
         if (tclass->remove)
-                tclass->remove(dev);
+                tclass->remove(tcont, dev, classdev);
 
         if (tclass->remove != anon_transport_dummy_function) {
                 if (tcont->statistics)
diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c
index 35d1c1e8e345..96243c7fe110 100644
--- a/drivers/scsi/scsi_transport_fc.c
+++ b/drivers/scsi/scsi_transport_fc.c
@@ -252,7 +252,8 @@ struct fc_internal {
 
 #define to_fc_internal(tmpl)    container_of(tmpl, struct fc_internal, t)
 
-static int fc_target_setup(struct device *dev)
+static int fc_target_setup(struct transport_container *tc, struct device *dev,
+                           struct class_device *cdev)
 {
         struct scsi_target *starget = to_scsi_target(dev);
         struct fc_rport *rport = starget_to_rport(starget);
@@ -281,7 +282,8 @@ static DECLARE_TRANSPORT_CLASS(fc_transport_class,
                                NULL,
                                NULL);
 
-static int fc_host_setup(struct device *dev)
+static int fc_host_setup(struct transport_container *tc, struct device *dev,
+                         struct class_device *cdev)
 {
         struct Scsi_Host *shost = dev_to_shost(dev);
 
diff --git a/drivers/scsi/scsi_transport_spi.c b/drivers/scsi/scsi_transport_spi.c
index 02134fce2174..89f6b7feb9c2 100644
--- a/drivers/scsi/scsi_transport_spi.c
+++ b/drivers/scsi/scsi_transport_spi.c
@@ -162,7 +162,8 @@ static inline enum spi_signal_type spi_signal_to_value(const char *name)
         return SPI_SIGNAL_UNKNOWN;
 }
 
-static int spi_host_setup(struct device *dev)
+static int spi_host_setup(struct transport_container *tc, struct device *dev,
+                          struct class_device *cdev)
 {
         struct Scsi_Host *shost = dev_to_shost(dev);
 
@@ -196,7 +197,9 @@ static int spi_host_match(struct attribute_container *cont,
         return &i->t.host_attrs.ac == cont;
 }
 
-static int spi_device_configure(struct device *dev)
+static int spi_device_configure(struct transport_container *tc,
+                                struct device *dev,
+                                struct class_device *cdev)
 {
         struct scsi_device *sdev = to_scsi_device(dev);
         struct scsi_target *starget = sdev->sdev_target;
@@ -214,7 +217,9 @@ static int spi_device_configure(struct device *dev)
         return 0;
 }
 
-static int spi_setup_transport_attrs(struct device *dev)
+static int spi_setup_transport_attrs(struct transport_container *tc,
+                                     struct device *dev,
+                                     struct class_device *cdev)
 {
         struct scsi_target *starget = to_scsi_target(dev);
 
diff --git a/include/linux/attribute_container.h b/include/linux/attribute_container.h
index af1010b6dab7..f54b05b052b3 100644
--- a/include/linux/attribute_container.h
+++ b/include/linux/attribute_container.h
@@ -11,10 +11,12 @@
 
 #include <linux/device.h>
 #include <linux/list.h>
+#include <linux/spinlock.h>
 
 struct attribute_container {
         struct list_head        node;
         struct list_head        containers;
+        spinlock_t              containers_lock;
         struct class            *class;
         struct class_device_attribute **attrs;
         int (*match)(struct attribute_container *, struct device *);
@@ -62,12 +64,7 @@ int attribute_container_add_class_device_adapter(struct attribute_container *con
                                                  struct class_device *classdev);
 void attribute_container_remove_attrs(struct class_device *classdev);
 void attribute_container_class_device_del(struct class_device *classdev);
-
-
-
-
-
-
+struct class_device *attribute_container_find_class_device(struct attribute_container *, struct device *);
 struct class_device_attribute **attribute_container_classdev_to_attrs(const struct class_device *classdev);
 
 #endif
diff --git a/include/linux/transport_class.h b/include/linux/transport_class.h
index 87d98d1faefb..1d6cc22e5f42 100644
--- a/include/linux/transport_class.h
+++ b/include/linux/transport_class.h
@@ -12,11 +12,16 @@
 #include <linux/device.h>
 #include <linux/attribute_container.h>
 
+struct transport_container;
+
 struct transport_class {
         struct class class;
-        int (*setup)(struct device *);
-        int (*configure)(struct device *);
-        int (*remove)(struct device *);
+        int (*setup)(struct transport_container *, struct device *,
+                     struct class_device *);
+        int (*configure)(struct transport_container *, struct device *,
+                         struct class_device *);
+        int (*remove)(struct transport_container *, struct device *,
+                      struct class_device *);
 };
 
 #define DECLARE_TRANSPORT_CLASS(cls, nm, su, rm, cfg)                   \