PCI: prevent duplicate slot names (5fe6cc60) · Commits · 戴 / test

drivers/pci/hotplug/pci_hotplug_core.c

+1 −25

Original line number	Diff line number	Diff line
		@@ -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;
		}

		/**

drivers/pci/hotplug/pciehp_core.c

+0 −15

Original line number	Diff line number	Diff line
		@@ -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;

drivers/pci/hotplug/shpchp_core.c

+1 −14

Original line number	Diff line number	Diff line
		@@ -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;
		}

drivers/pci/slot.c

+113 −28

Original line number	Diff line number	Diff line
		@@ -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);

		@@ -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__,

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