drivers/pci/hotplug/rpadlpar_core.c - linux - Git at Google

 /*
  * Interface for Dynamic Logical Partitioning of I/O Slots on
  * RPA-compliant PPC64 platform.
  *
  * John Rose <johnrose@austin.ibm.com>
  * Linda Xie <lxie@us.ibm.com>
  *
  * October 2003
  *
  * Copyright (C) 2003 IBM.
  *
  *      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; either version
  *      2 of the License, or (at your option) any later version.
  */
 #include <linux/init.h>
 #include <linux/pci.h>
 #include <asm/pci-bridge.h>
 #include <asm/semaphore.h>
 #include <asm/rtas.h>
 #include <asm/vio.h>
 #include "../pci.h"
 #include "rpaphp.h"
 #include "rpadlpar.h"

 static DECLARE_MUTEX(rpadlpar_sem);

 #define DLPAR_MODULE_NAME "rpadlpar_io"

 #define NODE_TYPE_VIO  1
 #define NODE_TYPE_SLOT 2
 #define NODE_TYPE_PHB  3

 static struct device_node *find_vio_slot_node(char *drc_name)
 {
 	struct device_node *parent = of_find_node_by_name(NULL, "vdevice");
 	struct device_node *dn = NULL;
 	char *name;
 	int rc;

 	if (!parent)
 		return NULL;

 	while ((dn = of_get_next_child(parent, dn))) {
 		rc = rpaphp_get_drc_props(dn, NULL, &name, NULL, NULL);
 		if ((rc == 0) && (!strcmp(drc_name, name)))
 			break;
 	}

 	return dn;
 }

 /* Find dlpar-capable pci node that contains the specified name and type */
 static struct device_node *find_php_slot_pci_node(char *drc_name,
 						  char *drc_type)
 {
 	struct device_node *np = NULL;
 	char *name;
 	char *type;
 	int rc;

 	while ((np = of_find_node_by_type(np, "pci"))) {
 		rc = rpaphp_get_drc_props(np, NULL, &name, &type, NULL);
 		if (rc == 0)
 			if (!strcmp(drc_name, name) && !strcmp(drc_type, type))
 				break;
 	}

 	return np;
 }

 static struct device_node *find_dlpar_node(char *drc_name, int *node_type)
 {
 	struct device_node *dn;

 	dn = find_php_slot_pci_node(drc_name, "SLOT");
 	if (dn) {
 		*node_type = NODE_TYPE_SLOT;
 		return dn;
 	}

 	dn = find_php_slot_pci_node(drc_name, "PHB");
 	if (dn) {
 		*node_type = NODE_TYPE_PHB;
 		return dn;
 	}

 	dn = find_vio_slot_node(drc_name);
 	if (dn) {
 		*node_type = NODE_TYPE_VIO;
 		return dn;
 	}

 	return NULL;
 }

 static struct slot *find_slot(struct device_node *dn)
 {
 	struct list_head *tmp, *n;
 	struct slot *slot;

         list_for_each_safe(tmp, n, &rpaphp_slot_head) {
                 slot = list_entry(tmp, struct slot, rpaphp_slot_list);
                 if (slot->dn == dn)
                         return slot;
         }

         return NULL;
 }

 static void rpadlpar_claim_one_bus(struct pci_bus *b)
 {
 	struct list_head *ld;
 	struct pci_bus *child_bus;

 	for (ld = b->devices.next; ld != &b->devices; ld = ld->next) {
 		struct pci_dev *dev = pci_dev_b(ld);
 		int i;

 		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 			struct resource *r = &dev->resource[i];

 			if (r->parent || !r->start || !r->flags)
 				continue;
 			rpaphp_claim_resource(dev, i);
 		}
 	}

 	list_for_each_entry(child_bus, &b->children, node)
 		rpadlpar_claim_one_bus(child_bus);
 }

 static int pci_add_secondary_bus(struct device_node *dn,
 		struct pci_dev *bridge_dev)
 {
 	struct pci_dn *pdn = dn->data;
 	struct pci_controller *hose = pdn->phb;
 	struct pci_bus *child;
 	u8 sec_busno;

 	/* Get busno of downstream bus */
 	pci_read_config_byte(bridge_dev, PCI_SECONDARY_BUS, &sec_busno);

 	/* Allocate and add to children of bridge_dev->bus */
 	child = pci_add_new_bus(bridge_dev->bus, bridge_dev, sec_busno);
 	if (!child) {
 		printk(KERN_ERR "%s: could not add secondary bus\n", __FUNCTION__);
 		return -ENOMEM;
 	}

 	sprintf(child->name, "PCI Bus #%02x", child->number);

 	/* Fixup subordinate bridge bases and resources */
 	pcibios_fixup_bus(child);

 	/* Claim new bus resources */
 	rpadlpar_claim_one_bus(bridge_dev->bus);

 	if (hose->last_busno < child->number)
 		hose->last_busno = child->number;

 	pdn->bussubno = child->number;

 	/* ioremap() for child bus, which may or may not succeed */
 	remap_bus_range(child);

 	return 0;
 }

 static struct pci_dev *dlpar_find_new_dev(struct pci_bus *parent,
 					struct device_node *dev_dn)
 {
 	struct pci_dev *tmp = NULL;
 	struct device_node *child_dn;

 	list_for_each_entry(tmp, &parent->devices, bus_list) {
 		child_dn = pci_device_to_OF_node(tmp);
 		if (child_dn == dev_dn)
 			return tmp;
 	}
 	return NULL;
 }

 static struct pci_dev *dlpar_pci_add_bus(struct device_node *dn)
 {
 	struct pci_dn *pdn = dn->data;
 	struct pci_controller *hose = pdn->phb;
 	struct pci_dev *dev = NULL;

 	/* Scan phb bus for EADS device, adding new one to bus->devices */
 	if (!pci_scan_single_device(hose->bus, pdn->devfn)) {
 		printk(KERN_ERR "%s: found no device on bus\n", __FUNCTION__);
 		return NULL;
 	}

 	/* Add new devices to global lists.  Register in proc, sysfs. */
 	pci_bus_add_devices(hose->bus);

 	/* Confirm new bridge dev was created */
 	dev = dlpar_find_new_dev(hose->bus, dn);
 	if (dev) {
 		if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 			printk(KERN_ERR "%s: unexpected header type %d\n",
 				__FUNCTION__, dev->hdr_type);
 			return NULL;
 		}

 		if (pci_add_secondary_bus(dn, dev))
 			return NULL;
 	}

 	return dev;
 }

 static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
 {
 	struct pci_dev *dev;
 	int rc;

 	if (rpaphp_find_pci_bus(dn))
 		return -EINVAL;

 	/* Add pci bus */
 	dev = dlpar_pci_add_bus(dn);
 	if (!dev) {
 		printk(KERN_ERR "%s: unable to add bus %s\n", __FUNCTION__,
 			drc_name);
 		return -EIO;
 	}

 	if (dn->child) {
 		rc = rpaphp_config_pci_adapter(dev->subordinate);
 		if (rc < 0) {
 			printk(KERN_ERR "%s: unable to enable slot %s\n",
 				__FUNCTION__, drc_name);
 			return -EIO;
 		}
 	}

 	/* Add hotplug slot */
 	if (rpaphp_add_slot(dn)) {
 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
 			__FUNCTION__, drc_name);
 		return -EIO;
 	}
 	return 0;
 }

 static int dlpar_remove_root_bus(struct pci_controller *phb)
 {
 	struct pci_bus *phb_bus;
 	int rc;

 	phb_bus = phb->bus;
 	if (!(list_empty(&phb_bus->children) &&
 	      list_empty(&phb_bus->devices))) {
 		return -EBUSY;
 	}

 	rc = pcibios_remove_root_bus(phb);
 	if (rc)
 		return -EIO;

 	device_unregister(phb_bus->bridge);
 	pci_remove_bus(phb_bus);

 	return 0;
 }

 static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
 {
 	struct slot *slot;
 	struct pci_dn *pdn;
 	int rc = 0;

 	if (!rpaphp_find_pci_bus(dn))
 		return -EINVAL;

 	slot = find_slot(dn);
 	if (slot) {
 		/* Remove hotplug slot */
 		if (rpaphp_remove_slot(slot)) {
 			printk(KERN_ERR
 				"%s: unable to remove hotplug slot %s\n",
 				__FUNCTION__, drc_name);
 			return -EIO;
 		}
 	}

 	pdn = dn->data;
 	BUG_ON(!pdn || !pdn->phb);
 	rc = dlpar_remove_root_bus(pdn->phb);
 	if (rc < 0)
 		return rc;

 	pdn->phb = NULL;

 	return 0;
 }

 static int dlpar_add_phb(char *drc_name, struct device_node *dn)
 {
 	struct pci_controller *phb;

 	if (PCI_DN(dn)->phb) {
 		/* PHB already exists */
 		return -EINVAL;
 	}

 	phb = init_phb_dynamic(dn);
 	if (!phb)
 		return -EIO;

 	if (rpaphp_add_slot(dn)) {
 		printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
 			__FUNCTION__, drc_name);
 		return -EIO;
 	}
 	return 0;
 }

 static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
 {
 	if (vio_find_node(dn))
 		return -EINVAL;

 	if (!vio_register_device_node(dn)) {
 		printk(KERN_ERR
 			"%s: failed to register vio node %s\n",
 			__FUNCTION__, drc_name);
 		return -EIO;
 	}
 	return 0;
 }

 /**
  * dlpar_add_slot - DLPAR add an I/O Slot
  * @drc_name: drc-name of newly added slot
  *
  * Make the hotplug module and the kernel aware
  * of a newly added I/O Slot.
  * Return Codes -
  * 0			Success
  * -ENODEV		Not a valid drc_name
  * -EINVAL		Slot already added
  * -ERESTARTSYS		Signalled before obtaining lock
  * -EIO			Internal PCI Error
  */
 int dlpar_add_slot(char *drc_name)
 {
 	struct device_node *dn = NULL;
 	int node_type;
 	int rc = -EIO;

 	if (down_interruptible(&rpadlpar_sem))
 		return -ERESTARTSYS;

 	/* Find newly added node */
 	dn = find_dlpar_node(drc_name, &node_type);
 	if (!dn) {
 		rc = -ENODEV;
 		goto exit;
 	}

 	switch (node_type) {
 		case NODE_TYPE_VIO:
 			rc = dlpar_add_vio_slot(drc_name, dn);
 			break;
 		case NODE_TYPE_SLOT:
 			rc = dlpar_add_pci_slot(drc_name, dn);
 			break;
 		case NODE_TYPE_PHB:
 			rc = dlpar_add_phb(drc_name, dn);
 			break;
 	}

 	printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
 exit:
 	up(&rpadlpar_sem);
 	return rc;
 }

 /**
  * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
  * @drc_name: drc-name of newly added slot
  *
  * Remove the kernel and hotplug representations
  * of an I/O Slot.
  * Return Codes:
  * 0			Success
  * -EINVAL		Vio dev doesn't exist
  */
 static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
 {
 	struct vio_dev *vio_dev;

 	vio_dev = vio_find_node(dn);
 	if (!vio_dev)
 		return -EINVAL;

 	vio_unregister_device(vio_dev);
 	return 0;
 }

 /**
  * dlpar_remove_slot - DLPAR remove a PCI I/O Slot
  * @drc_name: drc-name of newly added slot
  *
  * Remove the kernel and hotplug representations
  * of a PCI I/O Slot.
  * Return Codes:
  * 0			Success
  * -ENODEV		Not a valid drc_name
  * -EIO			Internal PCI Error
  */
 int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
 {
 	struct pci_bus *bus;
 	struct slot *slot;

 	bus = rpaphp_find_pci_bus(dn);
 	if (!bus)
 		return -EINVAL;

 	slot = find_slot(dn);
 	if (slot) {
 		/* Remove hotplug slot */
 		if (rpaphp_remove_slot(slot)) {
 			printk(KERN_ERR
 				"%s: unable to remove hotplug slot %s\n",
 				__FUNCTION__, drc_name);
 			return -EIO;
 		}
 	}

 	if (unmap_bus_range(bus)) {
 		printk(KERN_ERR "%s: failed to unmap bus range\n",
 			__FUNCTION__);
 		return -ERANGE;
 	}

 	BUG_ON(!bus->self);
 	pci_remove_bus_device(bus->self);
 	return 0;
 }

 /**
  * dlpar_remove_slot - DLPAR remove an I/O Slot
  * @drc_name: drc-name of newly added slot
  *
  * Remove the kernel and hotplug representations
  * of an I/O Slot.
  * Return Codes:
  * 0			Success
  * -ENODEV		Not a valid drc_name
  * -EINVAL		Slot already removed
  * -ERESTARTSYS		Signalled before obtaining lock
  * -EIO			Internal Error
  */
 int dlpar_remove_slot(char *drc_name)
 {
 	struct device_node *dn;
 	int node_type;
 	int rc = 0;

 	if (down_interruptible(&rpadlpar_sem))
 		return -ERESTARTSYS;

 	dn = find_dlpar_node(drc_name, &node_type);
 	if (!dn) {
 		rc = -ENODEV;
 		goto exit;
 	}

 	switch (node_type) {
 		case NODE_TYPE_VIO:
 			rc = dlpar_remove_vio_slot(drc_name, dn);
 			break;
 		case NODE_TYPE_PHB:
 			rc = dlpar_remove_phb(drc_name, dn);
 			break;
 		case NODE_TYPE_SLOT:
 			rc = dlpar_remove_pci_slot(drc_name, dn);
 			break;
 	}
 	printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
 exit:
 	up(&rpadlpar_sem);
 	return rc;
 }

 static inline int is_dlpar_capable(void)
 {
 	int rc = rtas_token("ibm,configure-connector");

 	return (int) (rc != RTAS_UNKNOWN_SERVICE);
 }

 int __init rpadlpar_io_init(void)
 {
 	int rc = 0;

 	if (!is_dlpar_capable()) {
 		printk(KERN_WARNING "%s: partition not DLPAR capable\n",
 			__FUNCTION__);
 		return -EPERM;
 	}

 	rc = dlpar_sysfs_init();
 	return rc;
 }

 void rpadlpar_io_exit(void)
 {
 	dlpar_sysfs_exit();
 	return;
 }

 module_init(rpadlpar_io_init);
 module_exit(rpadlpar_io_exit);
 MODULE_LICENSE("GPL");
	/*
	* Interface for Dynamic Logical Partitioning of I/O Slots on
	* RPA-compliant PPC64 platform.
	*
	* John Rose <johnrose@austin.ibm.com>
	* Linda Xie <lxie@us.ibm.com>
	*
	* October 2003
	*
	* Copyright (C) 2003 IBM.
	*
	* 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; either version
	* 2 of the License, or (at your option) any later version.
	*/
	#include <linux/init.h>
	#include <linux/pci.h>
	#include <asm/pci-bridge.h>
	#include <asm/semaphore.h>
	#include <asm/rtas.h>
	#include <asm/vio.h>
	#include "../pci.h"
	#include "rpaphp.h"
	#include "rpadlpar.h"

	static DECLARE_MUTEX(rpadlpar_sem);

	#define DLPAR_MODULE_NAME "rpadlpar_io"

	#define NODE_TYPE_VIO 1
	#define NODE_TYPE_SLOT 2
	#define NODE_TYPE_PHB 3

	static struct device_node find_vio_slot_node(char drc_name)
	{
	struct device_node *parent = of_find_node_by_name(NULL, "vdevice");
	struct device_node *dn = NULL;
	char *name;
	int rc;

	if (!parent)
	return NULL;

	while ((dn = of_get_next_child(parent, dn))) {
	rc = rpaphp_get_drc_props(dn, NULL, &name, NULL, NULL);
	if ((rc == 0) && (!strcmp(drc_name, name)))
	break;
	}

	return dn;
	}

	/* Find dlpar-capable pci node that contains the specified name and type */
	static struct device_node find_php_slot_pci_node(char drc_name,
	char *drc_type)
	{
	struct device_node *np = NULL;
	char *name;
	char *type;
	int rc;

	while ((np = of_find_node_by_type(np, "pci"))) {
	rc = rpaphp_get_drc_props(np, NULL, &name, &type, NULL);
	if (rc == 0)
	if (!strcmp(drc_name, name) && !strcmp(drc_type, type))
	break;
	}

	return np;
	}

	static struct device_node find_dlpar_node(char drc_name, int *node_type)
	{
	struct device_node *dn;

	dn = find_php_slot_pci_node(drc_name, "SLOT");
	if (dn) {
	*node_type = NODE_TYPE_SLOT;
	return dn;
	}

	dn = find_php_slot_pci_node(drc_name, "PHB");
	if (dn) {
	*node_type = NODE_TYPE_PHB;
	return dn;
	}

	dn = find_vio_slot_node(drc_name);
	if (dn) {
	*node_type = NODE_TYPE_VIO;
	return dn;
	}

	return NULL;
	}

	static struct slot find_slot(struct device_node dn)
	{
	struct list_head tmp, n;
	struct slot *slot;

	list_for_each_safe(tmp, n, &rpaphp_slot_head) {
	slot = list_entry(tmp, struct slot, rpaphp_slot_list);
	if (slot->dn == dn)
	return slot;
	}

	return NULL;
	}

	static void rpadlpar_claim_one_bus(struct pci_bus *b)
	{
	struct list_head *ld;
	struct pci_bus *child_bus;

	for (ld = b->devices.next; ld != &b->devices; ld = ld->next) {
	struct pci_dev *dev = pci_dev_b(ld);
	int i;

	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
	struct resource *r = &dev->resource[i];

	if (r->parent \|\| !r->start \|\| !r->flags)
	continue;
	rpaphp_claim_resource(dev, i);
	}
	}

	list_for_each_entry(child_bus, &b->children, node)
	rpadlpar_claim_one_bus(child_bus);
	}

	static int pci_add_secondary_bus(struct device_node *dn,
	struct pci_dev *bridge_dev)
	{
	struct pci_dn *pdn = dn->data;
	struct pci_controller *hose = pdn->phb;
	struct pci_bus *child;
	u8 sec_busno;

	/* Get busno of downstream bus */
	pci_read_config_byte(bridge_dev, PCI_SECONDARY_BUS, &sec_busno);

	/* Allocate and add to children of bridge_dev->bus */
	child = pci_add_new_bus(bridge_dev->bus, bridge_dev, sec_busno);
	if (!child) {
	printk(KERN_ERR "%s: could not add secondary bus\n", __FUNCTION__);
	return -ENOMEM;
	}

	sprintf(child->name, "PCI Bus #%02x", child->number);

	/* Fixup subordinate bridge bases and resources */
	pcibios_fixup_bus(child);

	/* Claim new bus resources */
	rpadlpar_claim_one_bus(bridge_dev->bus);

	if (hose->last_busno < child->number)
	hose->last_busno = child->number;

	pdn->bussubno = child->number;

	/* ioremap() for child bus, which may or may not succeed */
	remap_bus_range(child);

	return 0;
	}

	static struct pci_dev dlpar_find_new_dev(struct pci_bus parent,
	struct device_node *dev_dn)
	{
	struct pci_dev *tmp = NULL;
	struct device_node *child_dn;

	list_for_each_entry(tmp, &parent->devices, bus_list) {
	child_dn = pci_device_to_OF_node(tmp);
	if (child_dn == dev_dn)
	return tmp;
	}
	return NULL;
	}

	static struct pci_dev dlpar_pci_add_bus(struct device_node dn)
	{
	struct pci_dn *pdn = dn->data;
	struct pci_controller *hose = pdn->phb;
	struct pci_dev *dev = NULL;

	/* Scan phb bus for EADS device, adding new one to bus->devices */
	if (!pci_scan_single_device(hose->bus, pdn->devfn)) {
	printk(KERN_ERR "%s: found no device on bus\n", __FUNCTION__);
	return NULL;
	}

	/* Add new devices to global lists. Register in proc, sysfs. */
	pci_bus_add_devices(hose->bus);

	/* Confirm new bridge dev was created */
	dev = dlpar_find_new_dev(hose->bus, dn);
	if (dev) {
	if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
	printk(KERN_ERR "%s: unexpected header type %d\n",
	__FUNCTION__, dev->hdr_type);
	return NULL;
	}

	if (pci_add_secondary_bus(dn, dev))
	return NULL;
	}

	return dev;
	}

	static int dlpar_add_pci_slot(char drc_name, struct device_node dn)
	{
	struct pci_dev *dev;
	int rc;

	if (rpaphp_find_pci_bus(dn))
	return -EINVAL;

	/* Add pci bus */
	dev = dlpar_pci_add_bus(dn);
	if (!dev) {
	printk(KERN_ERR "%s: unable to add bus %s\n", __FUNCTION__,
	drc_name);
	return -EIO;
	}

	if (dn->child) {
	rc = rpaphp_config_pci_adapter(dev->subordinate);
	if (rc < 0) {
	printk(KERN_ERR "%s: unable to enable slot %s\n",
	__FUNCTION__, drc_name);
	return -EIO;
	}
	}

	/* Add hotplug slot */
	if (rpaphp_add_slot(dn)) {
	printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
	__FUNCTION__, drc_name);
	return -EIO;
	}
	return 0;
	}

	static int dlpar_remove_root_bus(struct pci_controller *phb)
	{
	struct pci_bus *phb_bus;
	int rc;

	phb_bus = phb->bus;
	if (!(list_empty(&phb_bus->children) &&
	list_empty(&phb_bus->devices))) {
	return -EBUSY;
	}

	rc = pcibios_remove_root_bus(phb);
	if (rc)
	return -EIO;

	device_unregister(phb_bus->bridge);
	pci_remove_bus(phb_bus);

	return 0;
	}

	static int dlpar_remove_phb(char drc_name, struct device_node dn)
	{
	struct slot *slot;
	struct pci_dn *pdn;
	int rc = 0;

	if (!rpaphp_find_pci_bus(dn))
	return -EINVAL;

	slot = find_slot(dn);
	if (slot) {
	/* Remove hotplug slot */
	if (rpaphp_remove_slot(slot)) {
	printk(KERN_ERR
	"%s: unable to remove hotplug slot %s\n",
	__FUNCTION__, drc_name);
	return -EIO;
	}
	}

	pdn = dn->data;
	BUG_ON(!pdn \|\| !pdn->phb);
	rc = dlpar_remove_root_bus(pdn->phb);
	if (rc < 0)
	return rc;

	pdn->phb = NULL;

	return 0;
	}

	static int dlpar_add_phb(char drc_name, struct device_node dn)
	{
	struct pci_controller *phb;

	if (PCI_DN(dn)->phb) {
	/* PHB already exists */
	return -EINVAL;
	}

	phb = init_phb_dynamic(dn);
	if (!phb)
	return -EIO;

	if (rpaphp_add_slot(dn)) {
	printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
	__FUNCTION__, drc_name);
	return -EIO;
	}
	return 0;
	}

	static int dlpar_add_vio_slot(char drc_name, struct device_node dn)
	{
	if (vio_find_node(dn))
	return -EINVAL;

	if (!vio_register_device_node(dn)) {
	printk(KERN_ERR
	"%s: failed to register vio node %s\n",
	__FUNCTION__, drc_name);
	return -EIO;
	}
	return 0;
	}

	/**
	* dlpar_add_slot - DLPAR add an I/O Slot
	* @drc_name: drc-name of newly added slot
	*
	* Make the hotplug module and the kernel aware
	* of a newly added I/O Slot.
	* Return Codes -
	* 0 Success
	* -ENODEV Not a valid drc_name
	* -EINVAL Slot already added
	* -ERESTARTSYS Signalled before obtaining lock
	* -EIO Internal PCI Error
	*/
	int dlpar_add_slot(char *drc_name)
	{
	struct device_node *dn = NULL;
	int node_type;
	int rc = -EIO;

	if (down_interruptible(&rpadlpar_sem))
	return -ERESTARTSYS;

	/* Find newly added node */
	dn = find_dlpar_node(drc_name, &node_type);
	if (!dn) {
	rc = -ENODEV;
	goto exit;
	}

	switch (node_type) {
	case NODE_TYPE_VIO:
	rc = dlpar_add_vio_slot(drc_name, dn);
	break;
	case NODE_TYPE_SLOT:
	rc = dlpar_add_pci_slot(drc_name, dn);
	break;
	case NODE_TYPE_PHB:
	rc = dlpar_add_phb(drc_name, dn);
	break;
	}

	printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
	exit:
	up(&rpadlpar_sem);
	return rc;
	}

	/**
	* dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
	* @drc_name: drc-name of newly added slot
	*
	* Remove the kernel and hotplug representations
	* of an I/O Slot.
	* Return Codes:
	* 0 Success
	* -EINVAL Vio dev doesn't exist
	*/
	static int dlpar_remove_vio_slot(char drc_name, struct device_node dn)
	{
	struct vio_dev *vio_dev;

	vio_dev = vio_find_node(dn);
	if (!vio_dev)
	return -EINVAL;

	vio_unregister_device(vio_dev);
	return 0;
	}

	/**
	* dlpar_remove_slot - DLPAR remove a PCI I/O Slot
	* @drc_name: drc-name of newly added slot
	*
	* Remove the kernel and hotplug representations
	* of a PCI I/O Slot.
	* Return Codes:
	* 0 Success
	* -ENODEV Not a valid drc_name
	* -EIO Internal PCI Error
	*/
	int dlpar_remove_pci_slot(char drc_name, struct device_node dn)
	{
	struct pci_bus *bus;
	struct slot *slot;

	bus = rpaphp_find_pci_bus(dn);
	if (!bus)
	return -EINVAL;

	slot = find_slot(dn);
	if (slot) {
	/* Remove hotplug slot */
	if (rpaphp_remove_slot(slot)) {
	printk(KERN_ERR
	"%s: unable to remove hotplug slot %s\n",
	__FUNCTION__, drc_name);
	return -EIO;
	}
	}

	if (unmap_bus_range(bus)) {
	printk(KERN_ERR "%s: failed to unmap bus range\n",
	__FUNCTION__);
	return -ERANGE;
	}

	BUG_ON(!bus->self);
	pci_remove_bus_device(bus->self);
	return 0;
	}

	/**
	* dlpar_remove_slot - DLPAR remove an I/O Slot
	* @drc_name: drc-name of newly added slot
	*
	* Remove the kernel and hotplug representations
	* of an I/O Slot.
	* Return Codes:
	* 0 Success
	* -ENODEV Not a valid drc_name
	* -EINVAL Slot already removed
	* -ERESTARTSYS Signalled before obtaining lock
	* -EIO Internal Error
	*/
	int dlpar_remove_slot(char *drc_name)
	{
	struct device_node *dn;
	int node_type;
	int rc = 0;

	if (down_interruptible(&rpadlpar_sem))
	return -ERESTARTSYS;

	dn = find_dlpar_node(drc_name, &node_type);
	if (!dn) {
	rc = -ENODEV;
	goto exit;
	}

	switch (node_type) {
	case NODE_TYPE_VIO:
	rc = dlpar_remove_vio_slot(drc_name, dn);
	break;
	case NODE_TYPE_PHB:
	rc = dlpar_remove_phb(drc_name, dn);
	break;
	case NODE_TYPE_SLOT:
	rc = dlpar_remove_pci_slot(drc_name, dn);
	break;
	}
	printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
	exit:
	up(&rpadlpar_sem);
	return rc;
	}

	static inline int is_dlpar_capable(void)
	{
	int rc = rtas_token("ibm,configure-connector");

	return (int) (rc != RTAS_UNKNOWN_SERVICE);
	}

	int __init rpadlpar_io_init(void)
	{
	int rc = 0;

	if (!is_dlpar_capable()) {
	printk(KERN_WARNING "%s: partition not DLPAR capable\n",
	__FUNCTION__);
	return -EPERM;
	}

	rc = dlpar_sysfs_init();
	return rc;
	}

	void rpadlpar_io_exit(void)
	{
	dlpar_sysfs_exit();
	return;
	}

	module_init(rpadlpar_io_init);
	module_exit(rpadlpar_io_exit);
	MODULE_LICENSE("GPL");