[net-next-2.6.git] / drivers / pci / slot.c

/*
 * drivers/pci/slot.c
 * Copyright (C) 2006 Matthew Wilcox <matthew@wil.cx>
 * Copyright (C) 2006-2009 Hewlett-Packard Development Company, L.P.
 *	Alex Chiang <achiang@hp.com>
 */

#include <linux/kobject.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/err.h>
#include "pci.h"

struct kset *pci_slots_kset;
EXPORT_SYMBOL_GPL(pci_slots_kset);

static ssize_t pci_slot_attr_show(struct kobject *kobj,
					struct attribute *attr, char *buf)
{
	struct pci_slot *slot = to_pci_slot(kobj);
	struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
	return attribute->show ? attribute->show(slot, buf) : -EIO;
}

static ssize_t pci_slot_attr_store(struct kobject *kobj,
			struct attribute *attr, const char *buf, size_t len)
{
	struct pci_slot *slot = to_pci_slot(kobj);
	struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
	return attribute->store ? attribute->store(slot, buf, len) : -EIO;
}

static const struct sysfs_ops pci_slot_sysfs_ops = {
	.show = pci_slot_attr_show,
	.store = pci_slot_attr_store,
};

static ssize_t address_read_file(struct pci_slot *slot, char *buf)
{
	if (slot->number == 0xff)
		return sprintf(buf, "%04x:%02x\n",
				pci_domain_nr(slot->bus),
				slot->bus->number);
	else
		return sprintf(buf, "%04x:%02x:%02x\n",
				pci_domain_nr(slot->bus),
				slot->bus->number,
				slot->number);
}

/* these strings match up with the values in pci_bus_speed */
static const char *pci_bus_speed_strings[] = {
	"33 MHz PCI",		/* 0x00 */
	"66 MHz PCI",		/* 0x01 */
	"66 MHz PCI-X", 	/* 0x02 */
	"100 MHz PCI-X",	/* 0x03 */
	"133 MHz PCI-X",	/* 0x04 */
	NULL,			/* 0x05 */
	NULL,			/* 0x06 */
	NULL,			/* 0x07 */
	NULL,			/* 0x08 */
	"66 MHz PCI-X 266",	/* 0x09 */
	"100 MHz PCI-X 266",	/* 0x0a */
	"133 MHz PCI-X 266",	/* 0x0b */
	"Unknown AGP",		/* 0x0c */
	"1x AGP",		/* 0x0d */
	"2x AGP",		/* 0x0e */
	"4x AGP",		/* 0x0f */
	"8x AGP",		/* 0x10 */
	"66 MHz PCI-X 533",	/* 0x11 */
	"100 MHz PCI-X 533",	/* 0x12 */
	"133 MHz PCI-X 533",	/* 0x13 */
	"2.5 GT/s PCIe",	/* 0x14 */
	"5.0 GT/s PCIe",	/* 0x15 */
	"8.0 GT/s PCIe",	/* 0x16 */
};

static ssize_t bus_speed_read(enum pci_bus_speed speed, char *buf)
{
	const char *speed_string;

	if (speed < ARRAY_SIZE(pci_bus_speed_strings))
		speed_string = pci_bus_speed_strings[speed];
	else
		speed_string = "Unknown";

	return sprintf(buf, "%s\n", speed_string);
}

static ssize_t max_speed_read_file(struct pci_slot *slot, char *buf)
{
	return bus_speed_read(slot->bus->max_bus_speed, buf);
}

static ssize_t cur_speed_read_file(struct pci_slot *slot, char *buf)
{
	return bus_speed_read(slot->bus->cur_bus_speed, buf);
}

static void pci_slot_release(struct kobject *kobj)
{
	struct pci_dev *dev;
	struct pci_slot *slot = to_pci_slot(kobj);

	dev_dbg(&slot->bus->dev, "dev %02x, released physical slot %s\n",
		slot->number, pci_slot_name(slot));

	list_for_each_entry(dev, &slot->bus->devices, bus_list)
		if (PCI_SLOT(dev->devfn) == slot->number)
			dev->slot = NULL;

	list_del(&slot->list);

	kfree(slot);
}

static struct pci_slot_attribute pci_slot_attr_address =
	__ATTR(address, (S_IFREG | S_IRUGO), address_read_file, NULL);
static struct pci_slot_attribute pci_slot_attr_max_speed =
	__ATTR(max_bus_speed, (S_IFREG | S_IRUGO), max_speed_read_file, NULL);
static struct pci_slot_attribute pci_slot_attr_cur_speed =
	__ATTR(cur_bus_speed, (S_IFREG | S_IRUGO), cur_speed_read_file, NULL);

static struct attribute *pci_slot_default_attrs[] = {
	&pci_slot_attr_address.attr,
	&pci_slot_attr_max_speed.attr,
	&pci_slot_attr_cur_speed.attr,
	NULL,
};

static struct kobj_type pci_slot_ktype = {
	.sysfs_ops = &pci_slot_sysfs_ops,
	.release = &pci_slot_release,
	.default_attrs = pci_slot_default_attrs,
};

static char *make_slot_name(const char *name)
{
	char *new_name;
	int len, max, dup;

	new_name = kstrdup(name, GFP_KERNEL);
	if (!new_name)
		return NULL;

	/*
	 * Make sure we hit the realloc case the first time through the
	 * loop.  'len' will be strlen(name) + 3 at that point which is
	 * enough space for "name-X" and the trailing NUL.
	 */
	len = strlen(name) + 2;
	max = 1;
	dup = 1;

	for (;;) {
		struct kobject *dup_slot;
		dup_slot = kset_find_obj(pci_slots_kset, new_name);
		if (!dup_slot)
			break;
		kobject_put(dup_slot);
		if (dup == max) {
			len++;
			max *= 10;
			kfree(new_name);
			new_name = kmalloc(len, GFP_KERNEL);
			if (!new_name)
				break;
		}
		sprintf(new_name, "%s-%d", name, dup++);
	}

	return new_name;
}

static int rename_slot(struct pci_slot *slot, const char *name)
{
	int result = 0;
	char *slot_name;

	if (strcmp(pci_slot_name(slot), name) == 0)
		return result;

	slot_name = make_slot_name(name);
	if (!slot_name)
		return -ENOMEM;

	result = kobject_rename(&slot->kobj, slot_name);
	kfree(slot_name);

	return result;
}

static struct pci_slot *get_slot(struct pci_bus *parent, int slot_nr)
{
	struct pci_slot *slot;
	/*
	 * We already hold pci_bus_sem so don't worry
	 */
	list_for_each_entry(slot, &parent->slots, list)
		if (slot->number == slot_nr) {
			kobject_get(&slot->kobj);
			return slot;
		}

	return NULL;
}

/**
 * pci_create_slot - create or increment refcount for physical PCI slot
 * @parent: struct pci_bus of parent bridge
 * @slot_nr: PCI_SLOT(pci_dev->devfn) or -1 for placeholder
 * @name: user visible string presented in /sys/bus/pci/slots/<name>
 * @hotplug: set if caller is hotplug driver, NULL otherwise
 *
 * PCI slots have first class attributes such as address, speed, width,
 * and a &struct pci_slot is used to manage them. This interface will
 * either return a new &struct pci_slot to the caller, or if the pci_slot
 * already exists, its refcount will be incremented.
 *
 * Slots are uniquely identified by a @pci_bus, @slot_nr tuple.
 *
 * There are known platforms with broken firmware that assign the same
 * name to multiple slots. Workaround these broken platforms by renaming
 * the slots on behalf of the caller. If firmware assigns name N to
 * multiple slots:
 *
 * The first slot is assigned N
 * The second slot is assigned N-1
 * The third slot is assigned N-2
 * etc.
 *
 * Placeholder slots:
 * In most cases, @pci_bus, @slot_nr will be sufficient to uniquely identify
 * a slot. There is one notable exception - pSeries (rpaphp), where the
 * @slot_nr cannot be determined until a device is actually inserted into
 * the slot. In this scenario, the caller may pass -1 for @slot_nr.
 *
 * The following semantics are imposed when the caller passes @slot_nr ==
 * -1. First, we no longer check for an existing %struct pci_slot, as there
 * may be many slots with @slot_nr of -1.  The other change in semantics is
 * user-visible, which is the 'address' parameter presented in sysfs will
 * consist solely of a dddd:bb tuple, where dddd is the PCI domain of the
 * %struct pci_bus and bb is the bus number. In other words, the devfn of
 * the 'placeholder' slot will not be displayed.
 */
struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
				 const char *name,
				 struct hotplug_slot *hotplug)
{
	struct pci_dev *dev;
	struct pci_slot *slot;
	int err = 0;
	char *slot_name = NULL;

	down_write(&pci_bus_sem);

	if (slot_nr == -1)
		goto placeholder;

	/*
	 * Hotplug drivers are allowed to rename an existing slot,
	 * but only if not already claimed.
	 */
	slot = get_slot(parent, slot_nr);
	if (slot) {
		if (hotplug) {
			if ((err = slot->hotplug ? -EBUSY : 0)
			     || (err = rename_slot(slot, name))) {
				kobject_put(&slot->kobj);
				slot = NULL;
				goto err;
			}
		}
		goto out;
	}

placeholder:
	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
	if (!slot) {
		err = -ENOMEM;
		goto err;
	}

	slot->bus = parent;
	slot->number = slot_nr;

	slot->kobj.kset = pci_slots_kset;

	slot_name = make_slot_name(name);
	if (!slot_name) {
		err = -ENOMEM;
		goto err;
	}

	err = kobject_init_and_add(&slot->kobj, &pci_slot_ktype, NULL,
				   "%s", slot_name);
	if (err)
		goto err;

	INIT_LIST_HEAD(&slot->list);
	list_add(&slot->list, &parent->slots);

	list_for_each_entry(dev, &parent->devices, bus_list)
		if (PCI_SLOT(dev->devfn) == slot_nr)
			dev->slot = slot;

	dev_dbg(&parent->dev, "dev %02x, created physical slot %s\n",
		slot_nr, pci_slot_name(slot));

out:
	kfree(slot_name);
	up_write(&pci_bus_sem);
	return slot;
err:
	kfree(slot);
	slot = ERR_PTR(err);
	goto out;
}
EXPORT_SYMBOL_GPL(pci_create_slot);

/**
 * pci_renumber_slot - update %struct pci_slot -> number
 * @slot: &struct pci_slot to update
 * @slot_nr: new number for slot
 *
 * The primary purpose of this interface is to allow callers who earlier
 * created a placeholder slot in pci_create_slot() by passing a -1 as
 * slot_nr, to update their %struct pci_slot with the correct @slot_nr.
 */
void pci_renumber_slot(struct pci_slot *slot, int slot_nr)
{
	struct pci_slot *tmp;

	down_write(&pci_bus_sem);

	list_for_each_entry(tmp, &slot->bus->slots, list) {
		WARN_ON(tmp->number == slot_nr);
		goto out;
	}

	slot->number = slot_nr;
out:
	up_write(&pci_bus_sem);
}
EXPORT_SYMBOL_GPL(pci_renumber_slot);

/**
 * pci_destroy_slot - decrement refcount for physical PCI slot
 * @slot: struct pci_slot to decrement
 *
 * %struct pci_slot is refcounted, so destroying them is really easy; we
 * just call kobject_put on its kobj and let our release methods do the
 * rest.
 */
void pci_destroy_slot(struct pci_slot *slot)
{
	dev_dbg(&slot->bus->dev, "dev %02x, dec refcount to %d\n",
		slot->number, atomic_read(&slot->kobj.kref.refcount) - 1);

	down_write(&pci_bus_sem);
	kobject_put(&slot->kobj);
	up_write(&pci_bus_sem);
}
EXPORT_SYMBOL_GPL(pci_destroy_slot);

#if defined(CONFIG_HOTPLUG_PCI) || defined(CONFIG_HOTPLUG_PCI_MODULE)
#include <linux/pci_hotplug.h>
/**
 * pci_hp_create_link - create symbolic link to the hotplug driver module.
 * @pci_slot: struct pci_slot
 *
 * Helper function for pci_hotplug_core.c to create symbolic link to
 * the hotplug driver module.
 */
void pci_hp_create_module_link(struct pci_slot *pci_slot)
{
	struct hotplug_slot *slot = pci_slot->hotplug;
	struct kobject *kobj = NULL;
	int no_warn;

	if (!slot || !slot->ops)
		return;
	kobj = kset_find_obj(module_kset, slot->ops->mod_name);
	if (!kobj)
		return;
	no_warn = sysfs_create_link(&pci_slot->kobj, kobj, "module");
	kobject_put(kobj);
}
EXPORT_SYMBOL_GPL(pci_hp_create_module_link);

/**
 * pci_hp_remove_link - remove symbolic link to the hotplug driver module.
 * @pci_slot: struct pci_slot
 *
 * Helper function for pci_hotplug_core.c to remove symbolic link to
 * the hotplug driver module.
 */
void pci_hp_remove_module_link(struct pci_slot *pci_slot)
{
	sysfs_remove_link(&pci_slot->kobj, "module");
}
EXPORT_SYMBOL_GPL(pci_hp_remove_module_link);
#endif

static int pci_slot_init(void)
{
	struct kset *pci_bus_kset;

	pci_bus_kset = bus_get_kset(&pci_bus_type);
	pci_slots_kset = kset_create_and_add("slots", NULL,
						&pci_bus_kset->kobj);
	if (!pci_slots_kset) {
		printk(KERN_ERR "PCI: Slot initialization failure\n");
		return -ENOMEM;
	}
	return 0;
}

subsys_initcall(pci_slot_init);
Commit	Line	Data
f46753c5 AC	1	/*
	2	* drivers/pci/slot.c
	3	* Copyright (C) 2006 Matthew Wilcox <matthew@wil.cx>
62795041 AC	4	* Copyright (C) 2006-2009 Hewlett-Packard Development Company, L.P.
62795041 AC	5	* Alex Chiang <achiang@hp.com>
f46753c5 AC	6	*/
	7
	8	#include <linux/kobject.h>
5a0e3ad6	9	#include <linux/slab.h>
f46753c5 AC	10	#include <linux/pci.h>
	11	#include <linux/err.h>
	12	#include "pci.h"
	13
	14	struct kset *pci_slots_kset;
	15	EXPORT_SYMBOL_GPL(pci_slots_kset);
	16
	17	static ssize_t pci_slot_attr_show(struct kobject *kobj,
	18	struct attribute attr, char buf)
	19	{
	20	struct pci_slot *slot = to_pci_slot(kobj);
	21	struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
	22	return attribute->show ? attribute->show(slot, buf) : -EIO;
	23	}
	24
	25	static ssize_t pci_slot_attr_store(struct kobject *kobj,
	26	struct attribute attr, const char buf, size_t len)
	27	{
	28	struct pci_slot *slot = to_pci_slot(kobj);
	29	struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
	30	return attribute->store ? attribute->store(slot, buf, len) : -EIO;
	31	}
	32
52cf25d0	33	static const struct sysfs_ops pci_slot_sysfs_ops = {
f46753c5 AC	34	.show = pci_slot_attr_show,
	35	.store = pci_slot_attr_store,
	36	};
	37
	38	static ssize_t address_read_file(struct pci_slot slot, char buf)
	39	{
	40	if (slot->number == 0xff)
	41	return sprintf(buf, "%04x:%02x\n",
	42	pci_domain_nr(slot->bus),
	43	slot->bus->number);
	44	else
	45	return sprintf(buf, "%04x:%02x:%02x\n",
	46	pci_domain_nr(slot->bus),
	47	slot->bus->number,
	48	slot->number);
	49	}
	50
3749c51a	51	/* these strings match up with the values in pci_bus_speed */
17134d96	52	static const char *pci_bus_speed_strings[] = {
3749c51a MW	53	"33 MHz PCI", /* 0x00 */
	54	"66 MHz PCI", /* 0x01 */
	55	"66 MHz PCI-X", /* 0x02 */
	56	"100 MHz PCI-X", /* 0x03 */
	57	"133 MHz PCI-X", /* 0x04 */
	58	NULL, /* 0x05 */
	59	NULL, /* 0x06 */
	60	NULL, /* 0x07 */
	61	NULL, /* 0x08 */
	62	"66 MHz PCI-X 266", /* 0x09 */
	63	"100 MHz PCI-X 266", /* 0x0a */
	64	"133 MHz PCI-X 266", /* 0x0b */
45b4cdd5 MW	65	"Unknown AGP", /* 0x0c */
	66	"1x AGP", /* 0x0d */
	67	"2x AGP", /* 0x0e */
	68	"4x AGP", /* 0x0f */
	69	"8x AGP", /* 0x10 */
3749c51a MW	70	"66 MHz PCI-X 533", /* 0x11 */
	71	"100 MHz PCI-X 533", /* 0x12 */
	72	"133 MHz PCI-X 533", /* 0x13 */
	73	"2.5 GT/s PCIe", /* 0x14 */
	74	"5.0 GT/s PCIe", /* 0x15 */
9dfd97fe	75	"8.0 GT/s PCIe", /* 0x16 */
3749c51a MW	76	};
	77
	78	static ssize_t bus_speed_read(enum pci_bus_speed speed, char *buf)
	79	{
	80	const char *speed_string;
	81
	82	if (speed < ARRAY_SIZE(pci_bus_speed_strings))
	83	speed_string = pci_bus_speed_strings[speed];
	84	else
	85	speed_string = "Unknown";
	86
	87	return sprintf(buf, "%s\n", speed_string);
	88	}
	89
	90	static ssize_t max_speed_read_file(struct pci_slot slot, char buf)
	91	{
	92	return bus_speed_read(slot->bus->max_bus_speed, buf);
	93	}
	94
	95	static ssize_t cur_speed_read_file(struct pci_slot slot, char buf)
	96	{
	97	return bus_speed_read(slot->bus->cur_bus_speed, buf);
	98	}
	99
f46753c5 AC	100	static void pci_slot_release(struct kobject *kobj)
f46753c5 AC	101	{
cef354db	102	struct pci_dev *dev;
f46753c5 AC	103	struct pci_slot *slot = to_pci_slot(kobj);
f46753c5 AC	104
62795041 AC	105	dev_dbg(&slot->bus->dev, "dev %02x, released physical slot %s\n",
62795041 AC	106	slot->number, pci_slot_name(slot));
f46753c5	107
cef354db AC	108	list_for_each_entry(dev, &slot->bus->devices, bus_list)
	109	if (PCI_SLOT(dev->devfn) == slot->number)
	110	dev->slot = NULL;
	111
f46753c5 AC	112	list_del(&slot->list);
	113
	114	kfree(slot);
	115	}
	116
	117	static struct pci_slot_attribute pci_slot_attr_address =
	118	__ATTR(address, (S_IFREG \| S_IRUGO), address_read_file, NULL);
3749c51a MW	119	static struct pci_slot_attribute pci_slot_attr_max_speed =
	120	__ATTR(max_bus_speed, (S_IFREG \| S_IRUGO), max_speed_read_file, NULL);
	121	static struct pci_slot_attribute pci_slot_attr_cur_speed =
	122	__ATTR(cur_bus_speed, (S_IFREG \| S_IRUGO), cur_speed_read_file, NULL);
f46753c5 AC	123
	124	static struct attribute *pci_slot_default_attrs[] = {
	125	&pci_slot_attr_address.attr,
3749c51a MW	126	&pci_slot_attr_max_speed.attr,
3749c51a MW	127	&pci_slot_attr_cur_speed.attr,
f46753c5 AC	128	NULL,
	129	};
	130
	131	static struct kobj_type pci_slot_ktype = {
	132	.sysfs_ops = &pci_slot_sysfs_ops,
	133	.release = &pci_slot_release,
	134	.default_attrs = pci_slot_default_attrs,
	135	};
	136
5fe6cc60 AC	137	static char make_slot_name(const char name)
	138	{
	139	char *new_name;
	140	int len, max, dup;
	141
	142	new_name = kstrdup(name, GFP_KERNEL);
	143	if (!new_name)
	144	return NULL;
	145
	146	/*
	147	* Make sure we hit the realloc case the first time through the
	148	* loop. 'len' will be strlen(name) + 3 at that point which is
	149	* enough space for "name-X" and the trailing NUL.
	150	*/
	151	len = strlen(name) + 2;
	152	max = 1;
	153	dup = 1;
	154
	155	for (;;) {
	156	struct kobject *dup_slot;
	157	dup_slot = kset_find_obj(pci_slots_kset, new_name);
	158	if (!dup_slot)
	159	break;
	160	kobject_put(dup_slot);
	161	if (dup == max) {
	162	len++;
	163	max *= 10;
	164	kfree(new_name);
	165	new_name = kmalloc(len, GFP_KERNEL);
	166	if (!new_name)
	167	break;
	168	}
	169	sprintf(new_name, "%s-%d", name, dup++);
	170	}
	171
	172	return new_name;
	173	}
	174
	175	static int rename_slot(struct pci_slot slot, const char name)
	176	{
	177	int result = 0;
	178	char *slot_name;
	179
0ad772ec	180	if (strcmp(pci_slot_name(slot), name) == 0)
5fe6cc60 AC	181	return result;
	182
	183	slot_name = make_slot_name(name);
	184	if (!slot_name)
	185	return -ENOMEM;
	186
	187	result = kobject_rename(&slot->kobj, slot_name);
	188	kfree(slot_name);
	189
	190	return result;
	191	}
	192
	193	static struct pci_slot get_slot(struct pci_bus parent, int slot_nr)
	194	{
	195	struct pci_slot *slot;
	196	/*
	197	* We already hold pci_bus_sem so don't worry
	198	*/
	199	list_for_each_entry(slot, &parent->slots, list)
	200	if (slot->number == slot_nr) {
	201	kobject_get(&slot->kobj);
	202	return slot;
	203	}
	204
	205	return NULL;
	206	}
	207
f46753c5 AC	208	/**
	209	* pci_create_slot - create or increment refcount for physical PCI slot
	210	* @parent: struct pci_bus of parent bridge
	211	* @slot_nr: PCI_SLOT(pci_dev->devfn) or -1 for placeholder
	212	* @name: user visible string presented in /sys/bus/pci/slots/<name>
828f3768	213	* @hotplug: set if caller is hotplug driver, NULL otherwise
f46753c5 AC	214	*
	215	* PCI slots have first class attributes such as address, speed, width,
	216	* and a &struct pci_slot is used to manage them. This interface will
	217	* either return a new &struct pci_slot to the caller, or if the pci_slot
	218	* already exists, its refcount will be incremented.
	219	*
5fe6cc60 AC	220	* Slots are uniquely identified by a @pci_bus, @slot_nr tuple.
	221	*
	222	* There are known platforms with broken firmware that assign the same
	223	* name to multiple slots. Workaround these broken platforms by renaming
	224	* the slots on behalf of the caller. If firmware assigns name N to
	225	* multiple slots:
	226	*
	227	* The first slot is assigned N
	228	* The second slot is assigned N-1
	229	* The third slot is assigned N-2
	230	* etc.
f46753c5 AC	231	*
	232	* Placeholder slots:
	233	* In most cases, @pci_bus, @slot_nr will be sufficient to uniquely identify
	234	* a slot. There is one notable exception - pSeries (rpaphp), where the
	235	* @slot_nr cannot be determined until a device is actually inserted into
	236	* the slot. In this scenario, the caller may pass -1 for @slot_nr.
	237	*
	238	* The following semantics are imposed when the caller passes @slot_nr ==
5fe6cc60 AC	239	* -1. First, we no longer check for an existing %struct pci_slot, as there
5fe6cc60 AC	240	* may be many slots with @slot_nr of -1. The other change in semantics is
f46753c5 AC	241	* user-visible, which is the 'address' parameter presented in sysfs will
	242	* consist solely of a dddd:bb tuple, where dddd is the PCI domain of the
	243	* %struct pci_bus and bb is the bus number. In other words, the devfn of
	244	* the 'placeholder' slot will not be displayed.
	245	*/
f46753c5	246	struct pci_slot pci_create_slot(struct pci_bus parent, int slot_nr,
828f3768 AC	247	const char *name,
828f3768 AC	248	struct hotplug_slot *hotplug)
f46753c5	249	{
cef354db	250	struct pci_dev *dev;
f46753c5	251	struct pci_slot *slot;
5fe6cc60 AC	252	int err = 0;
5fe6cc60 AC	253	char *slot_name = NULL;
f46753c5 AC	254
	255	down_write(&pci_bus_sem);
	256
	257	if (slot_nr == -1)
	258	goto placeholder;
	259
5fe6cc60 AC	260	/*
	261	* Hotplug drivers are allowed to rename an existing slot,
	262	* but only if not already claimed.
	263	*/
	264	slot = get_slot(parent, slot_nr);
	265	if (slot) {
	266	if (hotplug) {
	267	if ((err = slot->hotplug ? -EBUSY : 0)
	268	\|\| (err = rename_slot(slot, name))) {
	269	kobject_put(&slot->kobj);
	270	slot = NULL;
	271	goto err;
	272	}
f46753c5	273	}
5fe6cc60	274	goto out;
f46753c5 AC	275	}
	276
	277	placeholder:
	278	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
	279	if (!slot) {
5fe6cc60 AC	280	err = -ENOMEM;
5fe6cc60 AC	281	goto err;
f46753c5 AC	282	}
	283
	284	slot->bus = parent;
	285	slot->number = slot_nr;
	286
	287	slot->kobj.kset = pci_slots_kset;
5fe6cc60 AC	288
	289	slot_name = make_slot_name(name);
	290	if (!slot_name) {
	291	err = -ENOMEM;
f46753c5 AC	292	goto err;
	293	}
	294
5fe6cc60 AC	295	err = kobject_init_and_add(&slot->kobj, &pci_slot_ktype, NULL,
	296	"%s", slot_name);
	297	if (err)
	298	goto err;
	299
f46753c5 AC	300	INIT_LIST_HEAD(&slot->list);
	301	list_add(&slot->list, &parent->slots);
	302
cef354db AC	303	list_for_each_entry(dev, &parent->devices, bus_list)
	304	if (PCI_SLOT(dev->devfn) == slot_nr)
	305	dev->slot = slot;
	306
62795041 AC	307	dev_dbg(&parent->dev, "dev %02x, created physical slot %s\n",
62795041 AC	308	slot_nr, pci_slot_name(slot));
f46753c5	309
5fe6cc60	310	out:
3b5dd45e	311	kfree(slot_name);
f46753c5 AC	312	up_write(&pci_bus_sem);
f46753c5 AC	313	return slot;
5fe6cc60	314	err:
f46753c5 AC	315	kfree(slot);
	316	slot = ERR_PTR(err);
	317	goto out;
	318	}
	319	EXPORT_SYMBOL_GPL(pci_create_slot);
	320
	321	/**
d25b7c8d	322	* pci_renumber_slot - update %struct pci_slot -> number
cffb2faf RD	323	* @slot: &struct pci_slot to update
cffb2faf RD	324	* @slot_nr: new number for slot
f46753c5 AC	325	*
	326	* The primary purpose of this interface is to allow callers who earlier
	327	* created a placeholder slot in pci_create_slot() by passing a -1 as
	328	* slot_nr, to update their %struct pci_slot with the correct @slot_nr.
	329	*/
d25b7c8d	330	void pci_renumber_slot(struct pci_slot *slot, int slot_nr)
f46753c5	331	{
f46753c5 AC	332	struct pci_slot *tmp;
	333
	334	down_write(&pci_bus_sem);
	335
	336	list_for_each_entry(tmp, &slot->bus->slots, list) {
	337	WARN_ON(tmp->number == slot_nr);
d25b7c8d	338	goto out;
f46753c5 AC	339	}
f46753c5 AC	340
f46753c5	341	slot->number = slot_nr;
d25b7c8d	342	out:
f46753c5 AC	343	up_write(&pci_bus_sem);
f46753c5 AC	344	}
d25b7c8d	345	EXPORT_SYMBOL_GPL(pci_renumber_slot);
f46753c5 AC	346
	347	/**
	348	* pci_destroy_slot - decrement refcount for physical PCI slot
	349	* @slot: struct pci_slot to decrement
	350	*
	351	* %struct pci_slot is refcounted, so destroying them is really easy; we
	352	* just call kobject_put on its kobj and let our release methods do the
	353	* rest.
	354	*/
f46753c5 AC	355	void pci_destroy_slot(struct pci_slot *slot)
f46753c5 AC	356	{
62795041 AC	357	dev_dbg(&slot->bus->dev, "dev %02x, dec refcount to %d\n",
62795041 AC	358	slot->number, atomic_read(&slot->kobj.kref.refcount) - 1);
f46753c5 AC	359
	360	down_write(&pci_bus_sem);
	361	kobject_put(&slot->kobj);
	362	up_write(&pci_bus_sem);
	363	}
	364	EXPORT_SYMBOL_GPL(pci_destroy_slot);
	365
c825bc94 KK	366	#if defined(CONFIG_HOTPLUG_PCI) \|\| defined(CONFIG_HOTPLUG_PCI_MODULE)
	367	#include <linux/pci_hotplug.h>
	368	/**
	369	* pci_hp_create_link - create symbolic link to the hotplug driver module.
503998ca	370	* @pci_slot: struct pci_slot
c825bc94 KK	371	*
	372	* Helper function for pci_hotplug_core.c to create symbolic link to
	373	* the hotplug driver module.
	374	*/
	375	void pci_hp_create_module_link(struct pci_slot *pci_slot)
	376	{
	377	struct hotplug_slot *slot = pci_slot->hotplug;
	378	struct kobject *kobj = NULL;
	379	int no_warn;
	380
	381	if (!slot \|\| !slot->ops)
	382	return;
	383	kobj = kset_find_obj(module_kset, slot->ops->mod_name);
	384	if (!kobj)
	385	return;
	386	no_warn = sysfs_create_link(&pci_slot->kobj, kobj, "module");
	387	kobject_put(kobj);
	388	}
	389	EXPORT_SYMBOL_GPL(pci_hp_create_module_link);
	390
	391	/**
	392	* pci_hp_remove_link - remove symbolic link to the hotplug driver module.
503998ca	393	* @pci_slot: struct pci_slot
c825bc94 KK	394	*
	395	* Helper function for pci_hotplug_core.c to remove symbolic link to
	396	* the hotplug driver module.
	397	*/
	398	void pci_hp_remove_module_link(struct pci_slot *pci_slot)
	399	{
	400	sysfs_remove_link(&pci_slot->kobj, "module");
	401	}
	402	EXPORT_SYMBOL_GPL(pci_hp_remove_module_link);
	403	#endif
	404
f46753c5 AC	405	static int pci_slot_init(void)
	406	{
	407	struct kset *pci_bus_kset;
	408
	409	pci_bus_kset = bus_get_kset(&pci_bus_type);
	410	pci_slots_kset = kset_create_and_add("slots", NULL,
	411	&pci_bus_kset->kobj);
	412	if (!pci_slots_kset) {
	413	printk(KERN_ERR "PCI: Slot initialization failure\n");
	414	return -ENOMEM;
	415	}
	416	return 0;
	417	}
	418
	419	subsys_initcall(pci_slot_init);