[SCSI] correct transport class abstraction to work outside SCSI
James Bottomley [Sun, 14 Aug 2005 22:09:01 +0000 (17:09 -0500)]
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>

drivers/base/attribute_container.c
drivers/base/transport_class.c
drivers/scsi/scsi_transport_fc.c
drivers/scsi/scsi_transport_spi.c
include/linux/attribute_container.h
include/linux/transport_class.h

index ec615d8..62c093d 100644 (file)
@@ -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)
 {
index 6c2b447..4fb4c5d 100644 (file)
@@ -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)
index 35d1c1e..96243c7 100644 (file)
@@ -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);
 
index 02134fc..89f6b7f 100644 (file)
@@ -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);
 
index af1010b..f54b05b 100644 (file)
 
 #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
index 87d98d1..1d6cc22 100644 (file)
 #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)                  \