PCI/portdrv: Remove pcie_port_bus_type link order dependency

The pcie_port_bus_type must be registered before drivers that depend on it
can be registered.  Those drivers include:

  pcied_init()                # PCIe native hotplug driver
  aer_service_init()          # AER driver
  dpc_service_init()          # DPC driver
  pcie_pme_service_init()     # PME driver

Previously we registered pcie_port_bus_type from pcie_portdrv_init(), a
device_initcall.  The callers of pcie_port_service_register() (above) are
also device_initcalls.  This is fragile because the device_initcall
ordering depends on link order, which is not explicit.

Register pcie_port_bus_type from pci_driver_init() along with pci_bus_type.
This removes the link order dependency between portdrv and the pciehp, AER,
DPC, and PCIe PME drivers.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 646da0d2d7a8f585affb1ff02a994da1a5bc3a1f..21eb2f7ad95dddd372478af170a4cd49cd43b273 100644 (file)
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -19,6 +19,7 @@
 #include <linux/suspend.h>
 #include <linux/kexec.h>
 #include "pci.h"
+#include "pcie/portdrv.h"
 
 struct pci_dynid {
        struct list_head node;
@@ -1552,8 +1553,49 @@ struct bus_type pci_bus_type = {
 };
 EXPORT_SYMBOL(pci_bus_type);
 
+#ifdef CONFIG_PCIEPORTBUS
+static int pcie_port_bus_match(struct device *dev, struct device_driver *drv)
+{
+       struct pcie_device *pciedev;
+       struct pcie_port_service_driver *driver;
+
+       if (drv->bus != &pcie_port_bus_type || dev->bus != &pcie_port_bus_type)
+               return 0;
+
+       pciedev = to_pcie_device(dev);
+       driver = to_service_driver(drv);
+
+       if (driver->service != pciedev->service)
+               return 0;
+
+       if (driver->port_type != PCIE_ANY_PORT &&
+           driver->port_type != pci_pcie_type(pciedev->port))
+               return 0;
+
+       return 1;
+}
+
+struct bus_type pcie_port_bus_type = {
+       .name           = "pci_express",
+       .match          = pcie_port_bus_match,
+};
+EXPORT_SYMBOL_GPL(pcie_port_bus_type);
+#endif
+
 static int __init pci_driver_init(void)
 {
-       return bus_register(&pci_bus_type);
+       int ret;
+
+       ret = bus_register(&pci_bus_type);
+       if (ret)
+               return ret;
+
+#ifdef CONFIG_PCIEPORTBUS
+       ret = bus_register(&pcie_port_bus_type);
+       if (ret)
+               return ret;
+#endif
+
+       return 0;
 }
 postcore_initcall(pci_driver_init);

diff --git a/drivers/pci/pcie/Makefile b/drivers/pci/pcie/Makefile
index 223e4c34c29a5b2f048becd0fdd6ab7346e04a62..e01c10c97b958d63e1e8195761305c3031507093 100644 (file)
--- a/drivers/pci/pcie/Makefile
+++ b/drivers/pci/pcie/Makefile
@@ -6,7 +6,7 @@
 # Build PCI Express ASPM if needed
 obj-$(CONFIG_PCIEASPM)         += aspm.o
 
-pcieportdrv-y                  := portdrv_core.o portdrv_pci.o portdrv_bus.o
+pcieportdrv-y                  := portdrv_core.o portdrv_pci.o
 pcieportdrv-$(CONFIG_ACPI)     += portdrv_acpi.o
 
 obj-$(CONFIG_PCIEPORTBUS)      += pcieportdrv.o

diff --git a/drivers/pci/pcie/portdrv_bus.c b/drivers/pci/pcie/portdrv_bus.c
deleted file mode 100644 (file)
index 4969ccf..0000000
--- a/drivers/pci/pcie/portdrv_bus.c
+++ /dev/null
@@ -1,55 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * File:       portdrv_bus.c
- * Purpose:    PCI Express Port Bus Driver's Bus Overloading Functions
- *
- * Copyright (C) 2004 Intel
- * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
- */
-
-#include <linux/module.h>
-#include <linux/pci.h>
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/pm.h>
-
-#include "portdrv.h"
-
-static int pcie_port_bus_match(struct device *dev, struct device_driver *drv);
-
-struct bus_type pcie_port_bus_type = {
-       .name           = "pci_express",
-       .match          = pcie_port_bus_match,
-};
-EXPORT_SYMBOL_GPL(pcie_port_bus_type);
-
-static int pcie_port_bus_match(struct device *dev, struct device_driver *drv)
-{
-       struct pcie_device *pciedev;
-       struct pcie_port_service_driver *driver;
-
-       if (drv->bus != &pcie_port_bus_type || dev->bus != &pcie_port_bus_type)
-               return 0;
-
-       pciedev = to_pcie_device(dev);
-       driver = to_service_driver(drv);
-
-       if (driver->service != pciedev->service)
-               return 0;
-
-       if ((driver->port_type != PCIE_ANY_PORT) &&
-           (driver->port_type != pci_pcie_type(pciedev->port)))
-               return 0;
-
-       return 1;
-}
-
-int pcie_port_bus_register(void)
-{
-       return bus_register(&pcie_port_bus_type);
-}
-
-void pcie_port_bus_unregister(void)
-{
-       bus_unregister(&pcie_port_bus_type);
-}

diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c
index 5d9d5305ebeffe41f23356f3edd194e5682a4b60..127321e17184961bf9d0b153a9fe8739fdd4e9de 100644 (file)
--- a/drivers/pci/pcie/portdrv_pci.c
+++ b/drivers/pci/pcie/portdrv_pci.c
@@ -258,22 +258,11 @@ static const struct dmi_system_id pcie_portdrv_dmi_table[] __initconst = {
 
 static int __init pcie_portdrv_init(void)
 {
-       int retval;
-
        if (pcie_ports_disabled)
                return -EACCES;
 
        dmi_check_system(pcie_portdrv_dmi_table);
 
-       retval = pcie_port_bus_register();
-       if (retval) {
-               printk(KERN_WARNING "PCIE: bus_register error: %d\n", retval);
-               goto out;
-       }
-       retval = pci_register_driver(&pcie_portdriver);
-       if (retval)
-               pcie_port_bus_unregister();
- out:
-       return retval;
+       return pci_register_driver(&pcie_portdriver);
 }
 device_initcall(pcie_portdrv_init);