1 files changed, 358 insertions, 0 deletions

diff --git a/drivers/pci/hotplug/fakephp.c b/drivers/pci/hotplug/fakephp.c
new file mode 100644
index 000000000000..8e47fa66e25e
--- /dev/null
+++ b/drivers/pci/hotplug/fakephp.c
@@ -0,0 +1,358 @@
+/*
+ * Fake PCI Hot Plug Controller Driver
+ *
+ * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
+ * Copyright (C) 2003 IBM Corp.
+ * Copyright (C) 2003 Rolf Eike Beer <eike-kernel@sf-tec.de>
+ *
+ * Based on ideas and code from:
+ *      Vladimir Kondratiev <vladimir.kondratiev@intel.com>
+ *      Rolf Eike Beer <eike-kernel@sf-tec.de>
+ *
+ * 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 Software Foundation, version 2 of the License.
+ *
+ * Send feedback to <greg@kroah.com>
+ */
+
+/*
+ *
+ * This driver will "emulate" removing PCI devices from the system.  If
+ * the "power" file is written to with "0" then the specified PCI device
+ * will be completely removed from the kernel.
+ *
+ * WARNING, this does NOT turn off the power to the PCI device.  This is
+ * a "logical" removal, not a physical or electrical removal.
+ *
+ * Use this module at your own risk, you have been warned!
+ *
+ * Enabling PCI devices is left as an exercise for the reader...
+ *
+ */
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include "pci_hotplug.h"
+#include "../pci.h"
+
+#if !defined(MODULE)
+        #define MY_NAME "fakephp"
+#else
+        #define MY_NAME THIS_MODULE->name
+#endif
+
+#define dbg(format, arg...)                                     \
+        do {                                                    \
+                if (debug)                                      \
+                        printk(KERN_DEBUG "%s: " format,        \
+                                MY_NAME , ## arg);              \
+        } while (0)
+#define err(format, arg...) printk(KERN_ERR "%s: " format, MY_NAME , ## arg)
+#define info(format, arg...) printk(KERN_INFO "%s: " format, MY_NAME , ## arg)
+
+#define DRIVER_AUTHOR   "Greg Kroah-Hartman <greg@kroah.com>"
+#define DRIVER_DESC     "Fake PCI Hot Plug Controller Driver"
+
+struct dummy_slot {
+        struct list_head node;
+        struct hotplug_slot *slot;
+        struct pci_dev *dev;
+};
+
+static int debug;
+static LIST_HEAD(slot_list);
+
+static int enable_slot (struct hotplug_slot *slot);
+static int disable_slot (struct hotplug_slot *slot);
+
+static struct hotplug_slot_ops dummy_hotplug_slot_ops = {
+        .owner                  = THIS_MODULE,
+        .enable_slot            = enable_slot,
+        .disable_slot           = disable_slot,
+};
+
+static void dummy_release(struct hotplug_slot *slot)
+{
+        struct dummy_slot *dslot = slot->private;
+
+        list_del(&dslot->node);
+        kfree(dslot->slot->info);
+        kfree(dslot->slot);
+        pci_dev_put(dslot->dev);
+        kfree(dslot);
+}
+
+static int add_slot(struct pci_dev *dev)
+{
+        struct dummy_slot *dslot;
+        struct hotplug_slot *slot;
+        int retval = -ENOMEM;
+
+        slot = kmalloc(sizeof(struct hotplug_slot), GFP_KERNEL);
+        if (!slot)
+                goto error;
+        memset(slot, 0, sizeof(*slot));
+
+        slot->info = kmalloc(sizeof(struct hotplug_slot_info), GFP_KERNEL);
+        if (!slot->info)
+                goto error_slot;
+        memset(slot->info, 0, sizeof(struct hotplug_slot_info));
+
+        slot->info->power_status = 1;
+        slot->info->max_bus_speed = PCI_SPEED_UNKNOWN;
+        slot->info->cur_bus_speed = PCI_SPEED_UNKNOWN;
+
+        slot->name = &dev->dev.bus_id[0];
+        dbg("slot->name = %s\n", slot->name);
+
+        dslot = kmalloc(sizeof(struct dummy_slot), GFP_KERNEL);
+        if (!dslot)
+                goto error_info;
+
+        slot->ops = &dummy_hotplug_slot_ops;
+        slot->release = &dummy_release;
+        slot->private = dslot;
+
+        retval = pci_hp_register(slot);
+        if (retval) {
+                err("pci_hp_register failed with error %d\n", retval);
+                goto error_dslot;
+        }
+
+        dslot->slot = slot;
+        dslot->dev = pci_dev_get(dev);
+        list_add (&dslot->node, &slot_list);
+        return retval;
+
+error_dslot:
+        kfree(dslot);
+error_info:
+        kfree(slot->info);
+error_slot:
+        kfree(slot);
+error:
+        return retval;
+}
+
+static int __init pci_scan_buses(void)
+{
+        struct pci_dev *dev = NULL;
+        int retval = 0;
+
+        while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
+                retval = add_slot(dev);
+                if (retval) {
+                        pci_dev_put(dev);
+                        break;
+                }
+        }
+
+        return retval;
+}
+
+static void remove_slot(struct dummy_slot *dslot)
+{
+        int retval;
+
+        dbg("removing slot %s\n", dslot->slot->name);
+        retval = pci_hp_deregister(dslot->slot);
+        if (retval)
+                err("Problem unregistering a slot %s\n", dslot->slot->name);
+}
+
+/**
+ * Rescan slot.
+ * Tries hard not to re-enable already existing devices
+ * also handles scanning of subfunctions
+ *
+ * @param temp   Device template. Should be set: bus and devfn.
+ */
+static void pci_rescan_slot(struct pci_dev *temp)
+{
+        struct pci_bus *bus = temp->bus;
+        struct pci_dev *dev;
+        int func;
+        u8 hdr_type;
+        if (!pci_read_config_byte(temp, PCI_HEADER_TYPE, &hdr_type)) {
+                temp->hdr_type = hdr_type & 0x7f;
+                if (!pci_find_slot(bus->number, temp->devfn)) {
+                        dev = pci_scan_single_device(bus, temp->devfn);
+                        if (dev) {
+                                dbg("New device on %s function %x:%x\n",
+                                        bus->name, temp->devfn >> 3,
+                                        temp->devfn & 7);
+                                pci_bus_add_device(dev);
+                                add_slot(dev);
+                        }
+                }
+                /* multifunction device? */
+                if (!(hdr_type & 0x80))
+                        return;
+
+                /* continue scanning for other functions */
+                for (func = 1, temp->devfn++; func < 8; func++, temp->devfn++) {
+                        if (pci_read_config_byte(temp, PCI_HEADER_TYPE, &hdr_type))
+                                continue;
+                        temp->hdr_type = hdr_type & 0x7f;
+
+                        if (!pci_find_slot(bus->number, temp->devfn)) {
+                                dev = pci_scan_single_device(bus, temp->devfn);
+                                if (dev) {
+                                        dbg("New device on %s function %x:%x\n",
+                                                bus->name, temp->devfn >> 3,
+                                                temp->devfn & 7);
+                                        pci_bus_add_device(dev);
+                                        add_slot(dev);
+                                }
+                        }
+                }
+        }
+}
+
+
+/**
+ * Rescan PCI bus.
+ * call pci_rescan_slot for each possible function of the bus
+ *
+ * @param bus
+ */
+static void pci_rescan_bus(const struct pci_bus *bus)
+{
+        unsigned int devfn;
+        struct pci_dev *dev;
+        dev = kmalloc(sizeof(struct pci_dev), GFP_KERNEL);
+        if (!dev)
+                return;
+
+        memset(dev, 0, sizeof(dev));
+        dev->bus = (struct pci_bus*)bus;
+        dev->sysdata = bus->sysdata;
+        for (devfn = 0; devfn < 0x100; devfn += 8) {
+                dev->devfn = devfn;
+                pci_rescan_slot(dev);
+        }
+        kfree(dev);
+}
+
+/* recursively scan all buses */
+static void pci_rescan_buses(const struct list_head *list)
+{
+        const struct list_head *l;
+        list_for_each(l,list) {
+                const struct pci_bus *b = pci_bus_b(l);
+                pci_rescan_bus(b);
+                pci_rescan_buses(&b->children);
+        }
+}
+
+/* initiate rescan of all pci buses */
+static inline void pci_rescan(void) {
+        pci_rescan_buses(&pci_root_buses);
+}
+
+
+static int enable_slot(struct hotplug_slot *hotplug_slot)
+{
+        /* mis-use enable_slot for rescanning of the pci bus */
+        pci_rescan();
+        return -ENODEV;
+}
+
+/* find the hotplug_slot for the pci_dev */
+static struct hotplug_slot *get_slot_from_dev(struct pci_dev *dev)
+{
+        struct dummy_slot *dslot;
+
+        list_for_each_entry(dslot, &slot_list, node) {
+                if (dslot->dev == dev)
+                        return dslot->slot;
+        }
+        return NULL;
+}
+
+
+static int disable_slot(struct hotplug_slot *slot)
+{
+        struct dummy_slot *dslot;
+        struct hotplug_slot *hslot;
+        struct pci_dev *dev;
+        int func;
+
+        if (!slot)
+                return -ENODEV;
+        dslot = slot->private;
+
+        dbg("%s - physical_slot = %s\n", __FUNCTION__, slot->name);
+
+        /* don't disable bridged devices just yet, we can't handle them easily... */
+        if (dslot->dev->subordinate) {
+                err("Can't remove PCI devices with other PCI devices behind it yet.\n");
+                return -ENODEV;
+        }
+        /* search for subfunctions and disable them first */
+        if (!(dslot->dev->devfn & 7)) {
+                for (func = 1; func < 8; func++) {
+                        dev = pci_find_slot(dslot->dev->bus->number,
+                                        dslot->dev->devfn + func);
+                        if (dev) {
+                                hslot = get_slot_from_dev(dev);
+                                if (hslot)
+                                        disable_slot(hslot);
+                                else {
+                                        err("Hotplug slot not found for subfunction of PCI device\n");
+                                        return -ENODEV;
+                                }
+                        } else
+                                dbg("No device in slot found\n");
+                }
+        }
+
+        /* remove the device from the pci core */
+        pci_remove_bus_device(dslot->dev);
+
+        /* blow away this sysfs entry and other parts. */
+        remove_slot(dslot);
+
+        return 0;
+}
+
+static void cleanup_slots (void)
+{
+        struct list_head *tmp;
+        struct list_head *next;
+        struct dummy_slot *dslot;
+
+        list_for_each_safe (tmp, next, &slot_list) {
+                dslot = list_entry (tmp, struct dummy_slot, node);
+                remove_slot(dslot);
+        }
+        
+}
+
+static int __init dummyphp_init(void)
+{
+        info(DRIVER_DESC "\n");
+
+        return pci_scan_buses();
+}
+
+
+static void __exit dummyphp_exit(void)
+{
+        cleanup_slots();
+}
+
+module_init(dummyphp_init);
+module_exit(dummyphp_exit);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+module_param(debug, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
+