PCI: update pci_create_slot() to take a 'hotplug' param

commit 828f37683e6d3ab5912989df0d04201db7ad798e upstream.

Slot detection drivers can co-exist with hotplug drivers. The names
of the detected/claimed slots may be different depending on module
load order.

For legacy reasons, we need to allow hotplug drivers to override
the slot name if a detection driver is loaded first (and they find
the same slots).

Creating and overriding slot names should be an atomic operation,
otherwise you get a locking nightmare as various drivers race to
call pci_create_slot().

pci_create_slot() is already serialized by grabbing the pci_bus_sem.

We update the API and add a 'hotplug' param, which is:

	set if the caller is a hotplug driver
	NULL if the caller is a detection driver

pci_create_slot() does not actually use the 'hotplug' parameter in this
patch. A later patch will add the logic that uses it.

Cc: kristen.c.accardi@intel.com
Cc: matthew@wil.cx
Acked-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/acpi/pci_slot.c b/drivers/acpi/pci_slot.c
index d5b4ef898879dd913853feb588c5c802f7425266..8d4a568be1cc2041ea4bb2841d7f41dd1198756e 100644 (file)
--- a/drivers/acpi/pci_slot.c
+++ b/drivers/acpi/pci_slot.c
@@ -150,7 +150,7 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
        }
 
        snprintf(name, sizeof(name), "%u", (u32)sun);
-       pci_slot = pci_create_slot(pci_bus, device, name);
+       pci_slot = pci_create_slot(pci_bus, device, name, NULL);
        if (IS_ERR(pci_slot)) {
                err("pci_create_slot returned %ld\n", PTR_ERR(pci_slot));
                kfree(slot);

diff --git a/drivers/pci/hotplug/pci_hotplug_core.c b/drivers/pci/hotplug/pci_hotplug_core.c
index 3e37d636432bea56cadd52f07e67cc663ec063bc..ba219e64fbcf82e43b3ec57e5a26d3dbf43c5709 100644 (file)
--- a/drivers/pci/hotplug/pci_hotplug_core.c
+++ b/drivers/pci/hotplug/pci_hotplug_core.c
@@ -579,7 +579,7 @@ int pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus, int slot_nr,
         * driver and call it here again. If we've already created the
         * pci_slot, the interface will simply bump the refcount.
         */
-       pci_slot = pci_create_slot(bus, slot_nr, name);
+       pci_slot = pci_create_slot(bus, slot_nr, name, slot);
        if (IS_ERR(pci_slot))
                return PTR_ERR(pci_slot);
 

diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c
index 7e5b85cbd9488936b9ecbd10928dde86618f842c..6c08a9d7ee623ca7ea670198c96e3e1702a93ecf 100644 (file)
--- a/drivers/pci/slot.c
+++ b/drivers/pci/slot.c
@@ -78,6 +78,7 @@ static struct kobj_type pci_slot_ktype = {
  * @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
@@ -106,7 +107,8 @@ static struct kobj_type pci_slot_ktype = {
  */
 
 struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
-                                const char *name)
+                                const char *name,
+                                struct hotplug_slot *hotplug)
 {
        struct pci_slot *slot;
        int err;

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 98dc6243a706424ae099853320ef34edab5a8bc8..86ed5f9600933f30998ce604878a3cd48523b84c 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -509,7 +509,8 @@ struct pci_bus *pci_create_bus(struct device *parent, int bus,
 struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
                                int busnr);
 struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
-                                const char *name);
+                                const char *name,
+                                struct hotplug_slot *hotplug);
 void pci_destroy_slot(struct pci_slot *slot);
 void pci_update_slot_number(struct pci_slot *slot, int slot_nr);
 int pci_scan_slot(struct pci_bus *bus, int devfn);