| /* |
| * 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 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); |
| } |
| |
| 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 attribute *pci_slot_default_attrs[] = { |
| &pci_slot_attr_address.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); |
| |
| 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); |