/*
- * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
#include <linux/notifier.h>
#include <linux/device.h>
#include <linux/dca.h>
+#include <linux/slab.h>
-MODULE_LICENSE("GPL");
+#define DCA_VERSION "1.12.1"
-/* For now we're assuming a single, global, DCA provider for the system. */
+MODULE_VERSION(DCA_VERSION);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Intel Corporation");
static DEFINE_SPINLOCK(dca_lock);
-static struct dca_provider *global_dca = NULL;
+static LIST_HEAD(dca_domains);
+
+static struct pci_bus *dca_pci_rc_from_dev(struct device *dev)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ struct pci_bus *bus = pdev->bus;
+
+ 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;
+ }
+
+ list_for_each_entry(dca, &domain->dca_providers, node)
+ if ((!dev) || (dca->ops->dev_managed(dca, dev)))
+ return dca;
+
+ return NULL;
+}
/**
* dca_add_requester - add a dca client to the list
*/
int dca_add_requester(struct device *dev)
{
- int err, slot;
+ struct dca_provider *dca;
+ int err, slot = -ENODEV;
+ unsigned long flags;
+ struct pci_bus *pci_rc;
+ struct dca_domain *domain;
+
+ if (!dev)
+ return -EFAULT;
+
+ spin_lock_irqsave(&dca_lock, flags);
+
+ /* check if the requester has not been added already */
+ dca = dca_find_provider_by_dev(dev);
+ if (dca) {
+ spin_unlock_irqrestore(&dca_lock, flags);
+ return -EEXIST;
+ }
- if (!global_dca)
+ 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;
+ }
+
+ spin_unlock_irqrestore(&dca_lock, flags);
- spin_lock(&dca_lock);
- slot = global_dca->ops->add_requester(global_dca, dev);
- spin_unlock(&dca_lock);
if (slot < 0)
return slot;
- err = dca_sysfs_add_req(global_dca, dev, slot);
+ err = dca_sysfs_add_req(dca, dev, slot);
if (err) {
- spin_lock(&dca_lock);
- global_dca->ops->remove_requester(global_dca, dev);
- spin_unlock(&dca_lock);
+ spin_lock_irqsave(&dca_lock, flags);
+ if (dca == dca_find_provider_by_dev(dev))
+ dca->ops->remove_requester(dca, dev);
+ spin_unlock_irqrestore(&dca_lock, flags);
return err;
}
*/
int dca_remove_requester(struct device *dev)
{
+ struct dca_provider *dca;
int slot;
- if (!global_dca)
+ unsigned long flags;
+
+ if (!dev)
+ return -EFAULT;
+
+ spin_lock_irqsave(&dca_lock, flags);
+ dca = dca_find_provider_by_dev(dev);
+ if (!dca) {
+ spin_unlock_irqrestore(&dca_lock, flags);
return -ENODEV;
+ }
+ slot = dca->ops->remove_requester(dca, dev);
+ spin_unlock_irqrestore(&dca_lock, flags);
- spin_lock(&dca_lock);
- slot = global_dca->ops->remove_requester(global_dca, dev);
- spin_unlock(&dca_lock);
if (slot < 0)
return slot;
- dca_sysfs_remove_req(global_dca, slot);
+ dca_sysfs_remove_req(dca, slot);
+
return 0;
}
EXPORT_SYMBOL_GPL(dca_remove_requester);
/**
- * dca_get_tag - return the dca tag for the given cpu
+ * dca_common_get_tag - return the dca tag (serves both new and old api)
+ * @dev - the device that wants dca service
* @cpu - the cpuid as returned by get_cpu()
*/
-u8 dca_get_tag(int cpu)
+u8 dca_common_get_tag(struct device *dev, int cpu)
{
- if (!global_dca)
+ struct dca_provider *dca;
+ u8 tag;
+ unsigned long flags;
+
+ spin_lock_irqsave(&dca_lock, flags);
+
+ dca = dca_find_provider_by_dev(dev);
+ if (!dca) {
+ spin_unlock_irqrestore(&dca_lock, flags);
return -ENODEV;
- return global_dca->ops->get_tag(global_dca, cpu);
+ }
+ tag = dca->ops->get_tag(dca, dev, cpu);
+
+ spin_unlock_irqrestore(&dca_lock, flags);
+ return tag;
+}
+
+/**
+ * dca3_get_tag - return the dca tag to the requester device
+ * for the given cpu (new api)
+ * @dev - the device that wants dca service
+ * @cpu - the cpuid as returned by get_cpu()
+ */
+u8 dca3_get_tag(struct device *dev, int cpu)
+{
+ if (!dev)
+ return -EFAULT;
+
+ return dca_common_get_tag(dev, cpu);
+}
+EXPORT_SYMBOL_GPL(dca3_get_tag);
+
+/**
+ * dca_get_tag - return the dca tag for the given cpu (old api)
+ * @cpu - the cpuid as returned by get_cpu()
+ */
+u8 dca_get_tag(int cpu)
+{
+ struct device *dev = NULL;
+
+ return dca_common_get_tag(dev, cpu);
}
EXPORT_SYMBOL_GPL(dca_get_tag);
int register_dca_provider(struct dca_provider *dca, struct device *dev)
{
int err;
+ unsigned long flags;
+ struct dca_domain *domain;
- if (global_dca)
- return -EEXIST;
err = dca_sysfs_add_provider(dca, dev);
if (err)
return err;
- global_dca = dca;
+
+ spin_lock_irqsave(&dca_lock, flags);
+ 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,
DCA_PROVIDER_ADD, NULL);
return 0;
* 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)
{
- if (!global_dca)
- return;
+ unsigned long flags;
+ struct pci_bus *pci_rc;
+ struct dca_domain *domain;
+
blocking_notifier_call_chain(&dca_provider_chain,
DCA_PROVIDER_REMOVE, NULL);
- global_dca = 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);
}
EXPORT_SYMBOL_GPL(unregister_dca_provider);
static int __init dca_init(void)
{
+ pr_info("dca service started, version %s\n", DCA_VERSION);
return dca_sysfs_init();
}
dca_sysfs_exit();
}
-module_init(dca_init);
+arch_initcall(dca_init);
module_exit(dca_exit);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff