3 files changed, 120 insertions, 15 deletions

diff --git a/drivers/dca/dca-core.c b/drivers/dca/dca-core.c
index 25b743abfb59..7e318de0904b 100644
--- a/drivers/dca/dca-core.c
+++ b/drivers/dca/dca-core.c
@@ -28,7 +28,7 @@
 #include <linux/device.h>
 #include <linux/dca.h>
 
-#define DCA_VERSION "1.8"
+#define DCA_VERSION "1.12.1"
 
 MODULE_VERSION(DCA_VERSION);
 MODULE_LICENSE("GPL");
@@ -36,20 +36,92 @@ MODULE_AUTHOR("Intel Corporation");
 
 static DEFINE_SPINLOCK(dca_lock);
 
-static LIST_HEAD(dca_providers);
+static LIST_HEAD(dca_domains);
 
-static struct dca_provider *dca_find_provider_by_dev(struct device *dev)
+static struct pci_bus *dca_pci_rc_from_dev(struct device *dev)
 {
-        struct dca_provider *dca, *ret = NULL;
+        struct pci_dev *pdev = to_pci_dev(dev);
+        struct pci_bus *bus = pdev->bus;
 
-        list_for_each_entry(dca, &dca_providers, node) {
-                if ((!dev) || (dca->ops->dev_managed(dca, dev))) {
-                        ret = dca;
-                        break;
-                }
+        while (bus->parent)
+                bus = bus->parent;
+
+        return bus;
+}
+
+static struct dca_domain *dca_allocate_domain(struct pci_bus *rc)
+{
+        struct dca_domain *domain;
+
+        domain = kzalloc(sizeof(*domain), GFP_NOWAIT);
+        if (!domain)
+                return NULL;
+
+        INIT_LIST_HEAD(&domain->dca_providers);
+        domain->pci_rc = rc;
+
+        return domain;
+}
+
+static void dca_free_domain(struct dca_domain *domain)
+{
+        list_del(&domain->node);
+        kfree(domain);
+}
+
+static struct dca_domain *dca_find_domain(struct pci_bus *rc)
+{
+        struct dca_domain *domain;
+
+        list_for_each_entry(domain, &dca_domains, node)
+                if (domain->pci_rc == rc)
+                        return domain;
+
+        return NULL;
+}
+
+static struct dca_domain *dca_get_domain(struct device *dev)
+{
+        struct pci_bus *rc;
+        struct dca_domain *domain;
+
+        rc = dca_pci_rc_from_dev(dev);
+        domain = dca_find_domain(rc);
+
+        if (!domain) {
+                domain = dca_allocate_domain(rc);
+                if (domain)
+                        list_add(&domain->node, &dca_domains);
+        }
+
+        return domain;
+}
+
+static struct dca_provider *dca_find_provider_by_dev(struct device *dev)
+{
+        struct dca_provider *dca;
+        struct pci_bus *rc;
+        struct dca_domain *domain;
+
+        if (dev) {
+                rc = dca_pci_rc_from_dev(dev);
+                domain = dca_find_domain(rc);
+                if (!domain)
+                        return NULL;
+        } else {
+                if (!list_empty(&dca_domains))
+                        domain = list_first_entry(&dca_domains,
+                                                  struct dca_domain,
+                                                  node);
+                else
+                        return NULL;
         }
 
-        return ret;
+        list_for_each_entry(dca, &domain->dca_providers, node)
+                if ((!dev) || (dca->ops->dev_managed(dca, dev)))
+                        return dca;
+
+        return NULL;
 }
 
 /**
@@ -61,6 +133,8 @@ int dca_add_requester(struct device *dev)
         struct dca_provider *dca;
         int err, slot = -ENODEV;
         unsigned long flags;
+        struct pci_bus *pci_rc;
+        struct dca_domain *domain;
 
         if (!dev)
                 return -EFAULT;
@@ -74,7 +148,14 @@ int dca_add_requester(struct device *dev)
                 return -EEXIST;
         }
 
-        list_for_each_entry(dca, &dca_providers, node) {
+        pci_rc = dca_pci_rc_from_dev(dev);
+        domain = dca_find_domain(pci_rc);
+        if (!domain) {
+                spin_unlock_irqrestore(&dca_lock, flags);
+                return -ENODEV;
+        }
+
+        list_for_each_entry(dca, &domain->dca_providers, node) {
                 slot = dca->ops->add_requester(dca, dev);
                 if (slot >= 0)
                         break;
@@ -222,13 +303,19 @@ int register_dca_provider(struct dca_provider *dca, struct device *dev)
 {
         int err;
         unsigned long flags;
+        struct dca_domain *domain;
 
         err = dca_sysfs_add_provider(dca, dev);
         if (err)
                 return err;
 
         spin_lock_irqsave(&dca_lock, flags);
-        list_add(&dca->node, &dca_providers);
+        domain = dca_get_domain(dev);
+        if (!domain) {
+                spin_unlock_irqrestore(&dca_lock, flags);
+                return -ENODEV;
+        }
+        list_add(&dca->node, &domain->dca_providers);
         spin_unlock_irqrestore(&dca_lock, flags);
 
         blocking_notifier_call_chain(&dca_provider_chain,
@@ -241,15 +328,24 @@ EXPORT_SYMBOL_GPL(register_dca_provider);
  * unregister_dca_provider - remove a dca provider
  * @dca - struct created by alloc_dca_provider()
  */
-void unregister_dca_provider(struct dca_provider *dca)
+void unregister_dca_provider(struct dca_provider *dca, struct device *dev)
 {
         unsigned long flags;
+        struct pci_bus *pci_rc;
+        struct dca_domain *domain;
 
         blocking_notifier_call_chain(&dca_provider_chain,
                                      DCA_PROVIDER_REMOVE, NULL);
 
         spin_lock_irqsave(&dca_lock, flags);
+
         list_del(&dca->node);
+
+        pci_rc = dca_pci_rc_from_dev(dev);
+        domain = dca_find_domain(pci_rc);
+        if (list_empty(&domain->dca_providers))
+                dca_free_domain(domain);
+
         spin_unlock_irqrestore(&dca_lock, flags);
 
         dca_sysfs_remove_provider(dca);
diff --git a/drivers/dma/ioat/pci.c b/drivers/dma/ioat/pci.c
index c788fa266470..d545fae30f37 100644
--- a/drivers/dma/ioat/pci.c
+++ b/drivers/dma/ioat/pci.c
@@ -175,7 +175,7 @@ static void __devexit ioat_remove(struct pci_dev *pdev)
 
         dev_err(&pdev->dev, "Removing dma and dca services\n");
         if (device->dca) {
-                unregister_dca_provider(device->dca);
+                unregister_dca_provider(device->dca, &pdev->dev);
                 free_dca_provider(device->dca);
                 device->dca = NULL;
         }
diff --git a/include/linux/dca.h b/include/linux/dca.h
index 9c20c7e87d0a..d27a7a05718d 100644
--- a/include/linux/dca.h
+++ b/include/linux/dca.h
@@ -20,6 +20,9 @@
  */
 #ifndef DCA_H
 #define DCA_H
+
+#include <linux/pci.h>
+
 /* DCA Provider API */
 
 /* DCA Notifier Interface */
@@ -36,6 +39,12 @@ struct dca_provider {
         int                      id;
 };
 
+struct dca_domain {
+        struct list_head        node;
+        struct list_head        dca_providers;
+        struct pci_bus          *pci_rc;
+};
+
 struct dca_ops {
         int     (*add_requester)    (struct dca_provider *, struct device *);
         int     (*remove_requester) (struct dca_provider *, struct device *);
@@ -47,7 +56,7 @@ struct dca_ops {
 struct dca_provider *alloc_dca_provider(struct dca_ops *ops, int priv_size);
 void free_dca_provider(struct dca_provider *dca);
 int register_dca_provider(struct dca_provider *dca, struct device *dev);
-void unregister_dca_provider(struct dca_provider *dca);
+void unregister_dca_provider(struct dca_provider *dca, struct device *dev);
 
 static inline void *dca_priv(struct dca_provider *dca)
 {