PCI: hotplug: Drop superfluous pci_hotplug_slot_list

The PCI hotplug core keeps a list of all registered slots.  Its sole
purpose is to WARN() on slot removal if another slot is using the same
name.

But this can never happen because already on slot creation, an error is
returned and multiple messages are emitted if a slot's name is
duplicated:

  pci_hp_register()
    __pci_hp_register()
      __pci_hp_initialize()
        pci_create_slot()
          kobject_init_and_add()
            kobject_add_varg()
              kobject_add_internal()
                create_dir()
                  sysfs_create_dir_ns()
                    kernfs_create_dir_ns()
                      sysfs_warn_dup()
                        pr_warn("cannot create duplicate filename ...")
                pr_err("%s failed for %s with -EEXIST, ...");

Drop the superfluous list.

Link: https://lore.kernel.org/r/603735bc50eb370bc7f1c358441ac671360bab25.1740501868.git.lukas@wunner.de
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/hotplug/pci_hotplug_core.c b/drivers/pci/hotplug/pci_hotplug_core.c
index 36236ac88fd567bc4f4106671364aa38c824b13a..9e3cde91c16778228ba0dd24de349f29a4a8f034 100644 (file)
--- a/drivers/pci/hotplug/pci_hotplug_core.c
+++ b/drivers/pci/hotplug/pci_hotplug_core.c
@@ -18,14 +18,12 @@
 #include <linux/moduleparam.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
-#include <linux/list.h>
 #include <linux/kobject.h>
 #include <linux/sysfs.h>
 #include <linux/pagemap.h>
 #include <linux/init.h>
 #include <linux/mount.h>
 #include <linux/namei.h>
-#include <linux/mutex.h>
 #include <linux/pci.h>
 #include <linux/pci_hotplug.h>
 #include <linux/uaccess.h>
@@ -42,9 +40,6 @@
 /* local variables */
 static bool debug;
 
-static LIST_HEAD(pci_hotplug_slot_list);
-static DEFINE_MUTEX(pci_hp_mutex);
-
 /* Weee, fun with macros... */
 #define GET_STATUS(name, type) \
 static int get_##name(struct hotplug_slot *slot, type *value)          \
@@ -375,17 +370,6 @@ static void fs_remove_slot(struct pci_slot *pci_slot)
        pci_hp_remove_module_link(pci_slot);
 }
 
-static struct hotplug_slot *get_slot_from_name(const char *name)
-{
-       struct hotplug_slot *slot;
-
-       list_for_each_entry(slot, &pci_hotplug_slot_list, slot_list) {
-               if (strcmp(hotplug_slot_name(slot), name) == 0)
-                       return slot;
-       }
-       return NULL;
-}
-
 /**
  * __pci_hp_register - register a hotplug_slot with the PCI hotplug subsystem
  * @slot: pointer to the &struct hotplug_slot to register
@@ -484,10 +468,6 @@ int pci_hp_add(struct hotplug_slot *slot)
                return result;
 
        kobject_uevent(&pci_slot->kobj, KOBJ_ADD);
-       mutex_lock(&pci_hp_mutex);
-       list_add(&slot->slot_list, &pci_hotplug_slot_list);
-       mutex_unlock(&pci_hp_mutex);
-       dbg("Added slot %s to the list\n", hotplug_slot_name(slot));
        return 0;
 }
 EXPORT_SYMBOL_GPL(pci_hp_add);
@@ -514,21 +494,9 @@ EXPORT_SYMBOL_GPL(pci_hp_deregister);
  */
 void pci_hp_del(struct hotplug_slot *slot)
 {
-       struct hotplug_slot *temp;
-
        if (WARN_ON(!slot))
                return;
 
-       mutex_lock(&pci_hp_mutex);
-       temp = get_slot_from_name(hotplug_slot_name(slot));
-       if (WARN_ON(temp != slot)) {
-               mutex_unlock(&pci_hp_mutex);
-               return;
-       }
-
-       list_del(&slot->slot_list);
-       mutex_unlock(&pci_hp_mutex);
-       dbg("Removed slot %s from the list\n", hotplug_slot_name(slot));
        fs_remove_slot(slot->pci_slot);
 }
 EXPORT_SYMBOL_GPL(pci_hp_del);

diff --git a/include/linux/pci_hotplug.h b/include/linux/pci_hotplug.h
index 3a10d6ec3ee7f9618418a4e8394de3e096c72c1a..ec77ccf1fc4d1b77e4e5b136f452973bb2f18b4d 100644 (file)
--- a/include/linux/pci_hotplug.h
+++ b/include/linux/pci_hotplug.h
@@ -50,7 +50,6 @@ struct hotplug_slot_ops {
 /**
  * struct hotplug_slot - used to register a physical slot with the hotplug pci core
  * @ops: pointer to the &struct hotplug_slot_ops to be used for this slot
- * @slot_list: internal list used to track hotplug PCI slots
  * @pci_slot: represents a physical slot
  * @owner: The module owner of this structure
  * @mod_name: The module name (KBUILD_MODNAME) of this structure
@@ -59,7 +58,6 @@ struct hotplug_slot {
        const struct hotplug_slot_ops   *ops;
 
        /* Variables below this are for use only by the hotplug pci core. */
-       struct list_head                slot_list;
        struct pci_slot                 *pci_slot;
        struct module                   *owner;
        const char                      *mod_name;