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