[PATCH 3/5] PCI: hotplug: Drop superfluous NULL pointer checks in has_*_file()

[Lukas Wunner <lukas@xxxxxxxxx>]

The PCI hotplug core contains five has_*_file() functions to determine
whether a certain sysfs file shall be added (or removed) for a given
hotplug slot.

The functions perform NULL pointer checks for the hotplug_slot and its
hotplug_slot_ops.  However the callers already perform these checks:

  pci_hp_register()
    __pci_hp_register()
      __pci_hp_initialize()

  pci_hp_deregister()
    pci_hp_del()

The only way to actually trigger these checks is to call pci_hp_add()
without having called pci_hp_initialize().

Amend pci_hp_add() to catch that and drop the now superfluous NULL
pointer checks in has_*_file().

Drop the same superfluous checks from pci_hp_create_module_link(),
which is (only) called from pci_hp_add().

Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
---
 drivers/pci/hotplug/pci_hotplug_core.c | 17 ++++++-----------
 drivers/pci/slot.c                     |  2 --
 2 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/drivers/pci/hotplug/pci_hotplug_core.c b/drivers/pci/hotplug/pci_hotplug_core.c
index de5b501b40be..d4c12451570b 100644
--- a/drivers/pci/hotplug/pci_hotplug_core.c
+++ b/drivers/pci/hotplug/pci_hotplug_core.c
@@ -209,8 +209,6 @@ static bool has_power_file(struct pci_slot *pci_slot)
 {
 	struct hotplug_slot *slot = pci_slot->hotplug;
 
-	if ((!slot) || (!slot->ops))
-		return false;
 	if ((slot->ops->enable_slot) ||
 	    (slot->ops->disable_slot) ||
 	    (slot->ops->get_power_status))
@@ -222,8 +220,6 @@ static bool has_attention_file(struct pci_slot *pci_slot)
 {
 	struct hotplug_slot *slot = pci_slot->hotplug;
 
-	if ((!slot) || (!slot->ops))
-		return false;
 	if ((slot->ops->set_attention_status) ||
 	    (slot->ops->get_attention_status))
 		return true;
@@ -234,8 +230,6 @@ static bool has_latch_file(struct pci_slot *pci_slot)
 {
 	struct hotplug_slot *slot = pci_slot->hotplug;
 
-	if ((!slot) || (!slot->ops))
-		return false;
 	if (slot->ops->get_latch_status)
 		return true;
 	return false;
@@ -245,8 +239,6 @@ static bool has_adapter_file(struct pci_slot *pci_slot)
 {
 	struct hotplug_slot *slot = pci_slot->hotplug;
 
-	if ((!slot) || (!slot->ops))
-		return false;
 	if (slot->ops->get_adapter_status)
 		return true;
 	return false;
@@ -256,8 +248,6 @@ static bool has_test_file(struct pci_slot *pci_slot)
 {
 	struct hotplug_slot *slot = pci_slot->hotplug;
 
-	if ((!slot) || (!slot->ops))
-		return false;
 	if (slot->ops->hardware_test)
 		return true;
 	return false;
@@ -439,9 +429,14 @@ EXPORT_SYMBOL_GPL(__pci_hp_initialize);
  */
 int pci_hp_add(struct hotplug_slot *slot)
 {
-	struct pci_slot *pci_slot = slot->pci_slot;
+	struct pci_slot *pci_slot;
 	int result;
 
+	if (WARN_ON(!slot))
+		return -EINVAL;
+
+	pci_slot = slot->pci_slot;
+
 	result = fs_add_slot(pci_slot);
 	if (result)
 		return result;
diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c
index 36b44be0489d..dd6e80b7db09 100644
--- a/drivers/pci/slot.c
+++ b/drivers/pci/slot.c
@@ -340,8 +340,6 @@ void pci_hp_create_module_link(struct pci_slot *pci_slot)
 	struct kobject *kobj = NULL;
 	int ret;
 
-	if (!slot || !slot->ops)
-		return;
 	kobj = kset_find_obj(module_kset, slot->mod_name);
 	if (!kobj)
 		return;
-- 
2.43.0