PCI: Move __pci_walk_bus() mutex to where we need it

Simplify __pci_walk_bus() by moving the pci_bus_sem mutex into
pci_walk_bus(), the only place it is needed, and removing the parameter
that told __pci_walk_bus() whether to acquire the mutex.

Link: https://lore.kernel.org/r/20241022224851.340648-4-kbusch@meta.com
Signed-off-by: Keith Busch <kbusch@kernel.org>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index e41dfec..7c07a14 100644 (file)
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -390,7 +390,7 @@ void pci_bus_add_devices(const struct pci_bus *bus)
 EXPORT_SYMBOL(pci_bus_add_devices);
 
 static void __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
-                          void *userdata, bool locked)
+                          void *userdata)
 {
        struct pci_dev *dev;
        struct pci_bus *bus;
@@ -398,8 +398,6 @@ static void __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void
        int retval;
 
        bus = top;
-       if (!locked)
-               down_read(&pci_bus_sem);
        next = top->devices.next;
        for (;;) {
                if (next == &bus->devices) {
@@ -422,8 +420,6 @@ static void __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void
                if (retval)
                        break;
        }
-       if (!locked)
-               up_read(&pci_bus_sem);
 }
 
 /**
@@ -441,7 +437,9 @@ static void __pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void
  */
 void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *), void *userdata)
 {
-       __pci_walk_bus(top, cb, userdata, false);
+       down_read(&pci_bus_sem);
+       __pci_walk_bus(top, cb, userdata);
+       up_read(&pci_bus_sem);
 }
 EXPORT_SYMBOL_GPL(pci_walk_bus);
 
@@ -449,7 +447,7 @@ void pci_walk_bus_locked(struct pci_bus *top, int (*cb)(struct pci_dev *, void *
 {
        lockdep_assert_held(&pci_bus_sem);
 
-       __pci_walk_bus(top, cb, userdata, true);
+       __pci_walk_bus(top, cb, userdata);
 }
 EXPORT_SYMBOL_GPL(pci_walk_bus_locked);