This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / drivers / xen / pciback / passthrough.c

diff --git a/drivers/xen/pciback/passthrough.c b/drivers/xen/pciback/passthrough.c
new file mode 100644 (file)
index 0000000..5ee7638
--- /dev/null
+++ b/drivers/xen/pciback/passthrough.c
@@ -0,0 +1,157 @@
+/*
+ * PCI Backend - Provides restricted access to the real PCI bus topology
+ *               to the frontend
+ *
+ *   Author: Ryan Wilson <hap9@epoch.ncsc.mil>
+ */
+
+#include <linux/list.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+#include "pciback.h"
+
+struct passthrough_dev_data {
+       /* Access to dev_list must be protected by lock */
+       struct list_head dev_list;
+       spinlock_t lock;
+};
+
+struct pci_dev *pciback_get_pci_dev(struct pciback_device *pdev,
+                                   unsigned int domain, unsigned int bus,
+                                   unsigned int devfn)
+{
+       struct passthrough_dev_data *dev_data = pdev->pci_dev_data;
+       struct pci_dev_entry *dev_entry;
+       struct pci_dev *dev = NULL;
+       unsigned long flags;
+
+       spin_lock_irqsave(&dev_data->lock, flags);
+
+       list_for_each_entry(dev_entry, &dev_data->dev_list, list) {
+               if (domain == (unsigned int)pci_domain_nr(dev_entry->dev->bus)
+                   && bus == (unsigned int)dev_entry->dev->bus->number
+                   && devfn == dev_entry->dev->devfn) {
+                       dev = dev_entry->dev;
+                       break;
+               }
+       }
+
+       spin_unlock_irqrestore(&dev_data->lock, flags);
+
+       return dev;
+}
+
+int pciback_add_pci_dev(struct pciback_device *pdev, struct pci_dev *dev)
+{
+       struct passthrough_dev_data *dev_data = pdev->pci_dev_data;
+       struct pci_dev_entry *dev_entry;
+       unsigned long flags;
+
+       dev_entry = kmalloc(sizeof(*dev_entry), GFP_KERNEL);
+       if (!dev_entry)
+               return -ENOMEM;
+       dev_entry->dev = dev;
+
+       spin_lock_irqsave(&dev_data->lock, flags);
+       list_add_tail(&dev_entry->list, &dev_data->dev_list);
+       spin_unlock_irqrestore(&dev_data->lock, flags);
+
+       return 0;
+}
+
+void pciback_release_pci_dev(struct pciback_device *pdev, struct pci_dev *dev)
+{
+       struct passthrough_dev_data *dev_data = pdev->pci_dev_data;
+       struct pci_dev_entry *dev_entry, *t;
+       struct pci_dev *found_dev = NULL;
+       unsigned long flags;
+
+       spin_lock_irqsave(&dev_data->lock, flags);
+
+       list_for_each_entry_safe(dev_entry, t, &dev_data->dev_list, list) {
+               if (dev_entry->dev == dev) {
+                       list_del(&dev_entry->list);
+                       found_dev = dev_entry->dev;
+                       kfree(dev_entry);
+               }
+       }
+
+       spin_unlock_irqrestore(&dev_data->lock, flags);
+
+       if (found_dev)
+               pcistub_put_pci_dev(found_dev);
+}
+
+int pciback_init_devices(struct pciback_device *pdev)
+{
+       struct passthrough_dev_data *dev_data;
+
+       dev_data = kmalloc(sizeof(*dev_data), GFP_KERNEL);
+       if (!dev_data)
+               return -ENOMEM;
+
+       spin_lock_init(&dev_data->lock);
+
+       INIT_LIST_HEAD(&dev_data->dev_list);
+
+       pdev->pci_dev_data = dev_data;
+
+       return 0;
+}
+
+int pciback_publish_pci_roots(struct pciback_device *pdev,
+                             publish_pci_root_cb publish_root_cb)
+{
+       int err = 0;
+       struct passthrough_dev_data *dev_data = pdev->pci_dev_data;
+       struct pci_dev_entry *dev_entry, *e;
+       struct pci_dev *dev;
+       int found;
+       unsigned int domain, bus;
+
+       spin_lock(&dev_data->lock);
+
+       list_for_each_entry(dev_entry, &dev_data->dev_list, list) {
+               /* Only publish this device as a root if none of its
+                * parent bridges are exported
+                */
+               found = 0;
+               dev = dev_entry->dev->bus->self;
+               for (; !found && dev != NULL; dev = dev->bus->self) {
+                       list_for_each_entry(e, &dev_data->dev_list, list) {
+                               if (dev == e->dev) {
+                                       found = 1;
+                                       break;
+                               }
+                       }
+               }
+
+               domain = (unsigned int)pci_domain_nr(dev_entry->dev->bus);
+               bus = (unsigned int)dev_entry->dev->bus->number;
+
+               if (!found) {
+                       err = publish_root_cb(pdev, domain, bus);
+                       if (err)
+                               break;
+               }
+       }
+
+       spin_unlock(&dev_data->lock);
+
+       return err;
+}
+
+void pciback_release_devices(struct pciback_device *pdev)
+{
+       struct passthrough_dev_data *dev_data = pdev->pci_dev_data;
+       struct pci_dev_entry *dev_entry, *t;
+
+       list_for_each_entry_safe(dev_entry, t, &dev_data->dev_list, list) {
+               list_del(&dev_entry->list);
+               pcistub_put_pci_dev(dev_entry->dev);
+               kfree(dev_entry);
+       }
+
+       kfree(dev_data);
+       pdev->pci_dev_data = NULL;
+}