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

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

diff --git a/drivers/xen/pciback/slot.c b/drivers/xen/pciback/slot.c
new file mode 100644 (file)
index 0000000..09293fc
--- /dev/null
+++ b/drivers/xen/pciback/slot.c
@@ -0,0 +1,151 @@
+/*
+ * PCI Backend - Provides a Virtual PCI bus (with real devices)
+ *               to the frontend
+ *
+ *   Author: Ryan Wilson <hap9@epoch.ncsc.mil> (vpci.c)
+ *   Author: Tristan Gingold <tristan.gingold@bull.net>, from vpci.c
+ */
+
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+#include "pciback.h"
+
+/* There are at most 32 slots in a pci bus.  */
+#define PCI_SLOT_MAX 32
+
+#define PCI_BUS_NBR 2
+
+struct slot_dev_data {
+       /* Access to dev_list must be protected by lock */
+       struct pci_dev *slots[PCI_BUS_NBR][PCI_SLOT_MAX];
+       spinlock_t lock;
+};
+
+struct pci_dev *pciback_get_pci_dev(struct pciback_device *pdev,
+                                   unsigned int domain, unsigned int bus,
+                                   unsigned int devfn)
+{
+       struct pci_dev *dev = NULL;
+       struct slot_dev_data *slot_dev = pdev->pci_dev_data;
+       unsigned long flags;
+
+       if (domain != 0 || PCI_FUNC(devfn) != 0)
+               return NULL;
+
+       if (PCI_SLOT(devfn) >= PCI_SLOT_MAX || bus >= PCI_BUS_NBR)
+               return NULL;
+
+       spin_lock_irqsave(&slot_dev->lock, flags);
+       dev = slot_dev->slots[bus][PCI_SLOT(devfn)];
+       spin_unlock_irqrestore(&slot_dev->lock, flags);
+
+       return dev;
+}
+
+int pciback_add_pci_dev(struct pciback_device *pdev, struct pci_dev *dev)
+{
+       int err = 0, slot, bus;
+       struct slot_dev_data *slot_dev = pdev->pci_dev_data;
+       unsigned long flags;
+
+       if ((dev->class >> 24) == PCI_BASE_CLASS_BRIDGE) {
+               err = -EFAULT;
+               xenbus_dev_fatal(pdev->xdev, err,
+                                "Can't export bridges on the virtual PCI bus");
+               goto out;
+       }
+
+       spin_lock_irqsave(&slot_dev->lock, flags);
+
+       /* Assign to a new slot on the virtual PCI bus */
+       for (bus = 0; bus < PCI_BUS_NBR; bus++)
+               for (slot = 0; slot < PCI_SLOT_MAX; slot++) {
+                       if (slot_dev->slots[bus][slot] == NULL) {
+                               printk(KERN_INFO
+                                      "pciback: slot: %s: assign to virtual slot %d, bus %d\n",
+                                      pci_name(dev), slot, bus);
+                               slot_dev->slots[bus][slot] = dev;
+                               goto unlock;
+                       }
+               }
+
+       err = -ENOMEM;
+       xenbus_dev_fatal(pdev->xdev, err,
+                        "No more space on root virtual PCI bus");
+
+      unlock:
+       spin_unlock_irqrestore(&slot_dev->lock, flags);
+      out:
+       return err;
+}
+
+void pciback_release_pci_dev(struct pciback_device *pdev, struct pci_dev *dev)
+{
+       int slot, bus;
+       struct slot_dev_data *slot_dev = pdev->pci_dev_data;
+       struct pci_dev *found_dev = NULL;
+       unsigned long flags;
+
+       spin_lock_irqsave(&slot_dev->lock, flags);
+
+       for (bus = 0; bus < PCI_BUS_NBR; bus++)
+               for (slot = 0; slot < PCI_SLOT_MAX; slot++) {
+                       if (slot_dev->slots[bus][slot] == dev) {
+                               slot_dev->slots[bus][slot] = NULL;
+                               found_dev = dev;
+                               goto out;
+                       }
+               }
+
+      out:
+       spin_unlock_irqrestore(&slot_dev->lock, flags);
+
+       if (found_dev)
+               pcistub_put_pci_dev(found_dev);
+}
+
+int pciback_init_devices(struct pciback_device *pdev)
+{
+       int slot, bus;
+       struct slot_dev_data *slot_dev;
+
+       slot_dev = kmalloc(sizeof(*slot_dev), GFP_KERNEL);
+       if (!slot_dev)
+               return -ENOMEM;
+
+       spin_lock_init(&slot_dev->lock);
+
+       for (bus = 0; bus < PCI_BUS_NBR; bus++)
+               for (slot = 0; slot < PCI_SLOT_MAX; slot++)
+                       slot_dev->slots[bus][slot] = NULL;
+
+       pdev->pci_dev_data = slot_dev;
+
+       return 0;
+}
+
+int pciback_publish_pci_roots(struct pciback_device *pdev,
+                             publish_pci_root_cb publish_cb)
+{
+       /* The Virtual PCI bus has only one root */
+       return publish_cb(pdev, 0, 0);
+}
+
+void pciback_release_devices(struct pciback_device *pdev)
+{
+       int slot, bus;
+       struct slot_dev_data *slot_dev = pdev->pci_dev_data;
+       struct pci_dev *dev;
+
+       for (bus = 0; bus < PCI_BUS_NBR; bus++)
+               for (slot = 0; slot < PCI_SLOT_MAX; slot++) {
+                       dev = slot_dev->slots[bus][slot];
+                       if (dev != NULL)
+                               pcistub_put_pci_dev(dev);
+               }
+
+       kfree(slot_dev);
+       pdev->pci_dev_data = NULL;
+}