v4.19.13 snapshot.
diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c
new file mode 100644
index 0000000..e634229
--- /dev/null
+++ b/drivers/pci/slot.c
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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/module.h>
+#include <linux/pci.h>
+#include <linux/err.h>
+#include "pci.h"
+
+struct kset *pci_slots_kset;
+EXPORT_SYMBOL_GPL(pci_slots_kset);
+static DEFINE_MUTEX(pci_slot_mutex);
+
+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 */
+ "16.0 GT/s PCIe", /* 0x17 */
+};
+
+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));
+
+ down_read(&pci_bus_sem);
+ list_for_each_entry(dev, &slot->bus->devices, bus_list)
+ if (PCI_SLOT(dev->devfn) == slot->number)
+ dev->slot = NULL;
+ up_read(&pci_bus_sem);
+
+ list_del(&slot->list);
+
+ kfree(slot);
+}
+
+static struct pci_slot_attribute pci_slot_attr_address =
+ __ATTR(address, S_IRUGO, address_read_file, NULL);
+static struct pci_slot_attribute pci_slot_attr_max_speed =
+ __ATTR(max_bus_speed, S_IRUGO, max_speed_read_file, NULL);
+static struct pci_slot_attribute pci_slot_attr_cur_speed =
+ __ATTR(cur_bus_speed, 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;
+}
+
+void pci_dev_assign_slot(struct pci_dev *dev)
+{
+ struct pci_slot *slot;
+
+ mutex_lock(&pci_slot_mutex);
+ list_for_each_entry(slot, &dev->bus->slots, list)
+ if (PCI_SLOT(dev->devfn) == slot->number)
+ dev->slot = slot;
+ mutex_unlock(&pci_slot_mutex);
+}
+
+static struct pci_slot *get_slot(struct pci_bus *parent, int slot_nr)
+{
+ struct pci_slot *slot;
+
+ /* We already hold pci_slot_mutex */
+ 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;
+
+ mutex_lock(&pci_slot_mutex);
+
+ 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);
+
+ down_read(&pci_bus_sem);
+ list_for_each_entry(dev, &parent->devices, bus_list)
+ if (PCI_SLOT(dev->devfn) == slot_nr)
+ dev->slot = slot;
+ up_read(&pci_bus_sem);
+
+ dev_dbg(&parent->dev, "dev %02x, created physical slot %s\n",
+ slot_nr, pci_slot_name(slot));
+
+out:
+ kfree(slot_name);
+ mutex_unlock(&pci_slot_mutex);
+ return slot;
+err:
+ kfree(slot);
+ slot = ERR_PTR(err);
+ goto out;
+}
+EXPORT_SYMBOL_GPL(pci_create_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, kref_read(&slot->kobj.kref) - 1);
+
+ mutex_lock(&pci_slot_mutex);
+ kobject_put(&slot->kobj);
+ mutex_unlock(&pci_slot_mutex);
+}
+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 ret;
+
+ if (!slot || !slot->ops)
+ return;
+ kobj = kset_find_obj(module_kset, slot->ops->mod_name);
+ if (!kobj)
+ return;
+ ret = sysfs_create_link(&pci_slot->kobj, kobj, "module");
+ if (ret)
+ dev_err(&pci_slot->bus->dev, "Error creating sysfs link (%d)\n",
+ ret);
+ 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);