diff --git a/drivers/pci/hotplug/pci_hotplug_core.c b/drivers/pci/hotplug/pci_hotplug_core.c index e71524825180..a6f1f282b683 100644 --- a/drivers/pci/hotplug/pci_hotplug_core.c +++ b/drivers/pci/hotplug/pci_hotplug_core.c @@ -569,12 +569,6 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, mutex_lock(&pci_hp_mutex); - /* Check if we have already registered a slot with the same name. */ - if (get_slot_from_name(name)) { - result = -EEXIST; - goto out; - } - /* * No problems if we call this interface from both ACPI_PCI_SLOT * driver and call it here again. If we've already created the @@ -583,27 +577,12 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, pci_slot = pci_create_slot(bus, slot_nr, name, slot); if (IS_ERR(pci_slot)) { result = PTR_ERR(pci_slot); - goto cleanup; - } - - if (pci_slot->hotplug) { - dbg("%s: already claimed\n", __func__); - result = -EBUSY; - goto cleanup; + goto out; } slot->pci_slot = pci_slot; pci_slot->hotplug = slot; - /* - * Allow pcihp drivers to override the ACPI_PCI_SLOT name. - */ - if (strcmp(kobject_name(&pci_slot->kobj), name)) { - result = kobject_rename(&pci_slot->kobj, name); - if (result) - goto cleanup; - } - list_add(&slot->slot_list, &pci_hotplug_slot_list); result = fs_add_slot(pci_slot); @@ -612,9 +591,6 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr, out: mutex_unlock(&pci_hp_mutex); return result; -cleanup: - pci_destroy_slot(pci_slot); - goto out; } /** diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c index 3ace5e057601..af89d7bd1edd 100644 --- a/drivers/pci/hotplug/pciehp_core.c +++ b/drivers/pci/hotplug/pciehp_core.c @@ -196,7 +196,6 @@ static int init_slots(struct controller *ctrl) struct slot *slot; struct hotplug_slot *hotplug_slot; struct hotplug_slot_info *info; - int len, dup = 1; int retval = -ENOMEM; list_for_each_entry(slot, &ctrl->slot_list, slot_list) { @@ -223,25 +222,11 @@ static int init_slots(struct controller *ctrl) ctrl_dbg(ctrl, "Registering bus=%x dev=%x hp_slot=%x sun=%x " "slot_device_offset=%x\n", slot->bus, slot->device, slot->hp_slot, slot->number, ctrl->slot_device_offset); -duplicate_name: retval = pci_hp_register(hotplug_slot, ctrl->pci_dev->subordinate, slot->device, slot->name); if (retval) { - /* - * If slot N already exists, we'll try to create - * slot N-1, N-2 ... N-M, until we overflow. - */ - if (retval == -EEXIST) { - len = snprintf(slot->name, SLOT_NAME_SIZE, - "%d-%d", slot->number, dup++); - if (len < SLOT_NAME_SIZE) - goto duplicate_name; - else - ctrl_err(ctrl, "duplicate slot name " - "overflow\n"); - } ctrl_err(ctrl, "pci_hp_register failed with error %d\n", retval); goto error_info; diff --git a/drivers/pci/hotplug/shpchp_core.c b/drivers/pci/hotplug/shpchp_core.c index bf5096612aab..cfdd07963641 100644 --- a/drivers/pci/hotplug/shpchp_core.c +++ b/drivers/pci/hotplug/shpchp_core.c @@ -102,7 +102,7 @@ static int init_slots(struct controller *ctrl) struct hotplug_slot *hotplug_slot; struct hotplug_slot_info *info; int retval = -ENOMEM; - int i, len, dup = 1; + int i; for (i = 0; i < ctrl->num_slots; i++) { slot = kzalloc(sizeof(*slot), GFP_KERNEL); @@ -144,23 +144,10 @@ static int init_slots(struct controller *ctrl) dbg("Registering bus=%x dev=%x hp_slot=%x sun=%x " "slot_device_offset=%x\n", slot->bus, slot->device, slot->hp_slot, slot->number, ctrl->slot_device_offset); -duplicate_name: retval = pci_hp_register(slot->hotplug_slot, ctrl->pci_dev->subordinate, slot->device, hotplug_slot->name); if (retval) { - /* - * If slot N already exists, we'll try to create - * slot N-1, N-2 ... N-M, until we overflow. - */ - if (retval == -EEXIST) { - len = snprintf(slot->name, SLOT_NAME_SIZE, - "%d-%d", slot->number, dup++); - if (len < SLOT_NAME_SIZE) - goto duplicate_name; - else - err("duplicate slot name overflow\n"); - } err("pci_hp_register failed with error %d\n", retval); goto error_info; } diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c index 0e009c3ba5fd..b6ee352ae459 100644 --- a/drivers/pci/slot.c +++ b/drivers/pci/slot.c @@ -78,6 +78,77 @@ static struct kobj_type pci_slot_ktype = { .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(kobject_name(&slot->kobj), 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 @@ -90,7 +161,17 @@ static struct kobj_type pci_slot_ktype = { * 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, @name tuple. + * 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 @@ -99,62 +180,67 @@ static struct kobj_type pci_slot_ktype = { * 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, the check for existing %struct pci_slot is skipped, as the - * caller may know about several unpopulated slots on a given %struct - * pci_bus, and each slot would have a @slot_nr of -1. Uniqueness for - * these slots is then determined by the @name parameter. We expect - * kobject_init_and_add() to warn us if the caller attempts to create - * multiple slots with the same name. The other change in semantics is + * -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; + int err = 0; + char *slot_name = NULL; down_write(&pci_bus_sem); if (slot_nr == -1) goto placeholder; - /* If we've already created this slot, bump refcount and return. */ - list_for_each_entry(slot, &parent->slots, list) { - if (slot->number == slot_nr) { - kobject_get(&slot->kobj); - pr_debug("%s: inc refcount to %d on %04x:%02x:%02x\n", - __func__, - atomic_read(&slot->kobj.kref.refcount), - pci_domain_nr(parent), parent->number, - slot_nr); - goto out; + /* + * 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) { - slot = ERR_PTR(-ENOMEM); - goto out; + err = -ENOMEM; + goto err; } slot->bus = parent; slot->number = slot_nr; slot->kobj.kset = pci_slots_kset; - err = kobject_init_and_add(&slot->kobj, &pci_slot_ktype, NULL, - "%s", name); - if (err) { - printk(KERN_ERR "Unable to register kobject %s\n", name); + + 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); @@ -166,10 +252,10 @@ placeholder: pr_debug("%s: created pci_slot on %04x:%02x:%02x\n", __func__, pci_domain_nr(parent), parent->number, slot_nr); - out: +out: up_write(&pci_bus_sem); return slot; - err: +err: kfree(slot); slot = ERR_PTR(err); goto out; @@ -210,7 +296,6 @@ EXPORT_SYMBOL_GPL(pci_renumber_slot); * just call kobject_put on its kobj and let our release methods do the * rest. */ - void pci_destroy_slot(struct pci_slot *slot) { pr_debug("%s: dec refcount to %d on %04x:%02x:%02x\n", __func__,