[RFC PATCH v2, part 2 03/18] PCI, hotplug: use hotplug-safe iterators to walk PCI buses

[Jiang Liu <liuj97@gmail.com>]

Enhance PCI hotplug drivers to use hotplug-safe iterators to walk
PCI buses.

In other words, replace pci_find_bus(), pci_find_next_bus() and
pci_root_buses with pci_bus_exists(), pci_get_bus(), pci_get_next_bus()
and pci_get_next_root_bus() etc.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-pci@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/pci/hotplug-pci.c          | 2 +-
 drivers/pci/hotplug/ibmphp_core.c  | 8 +++++---
 drivers/pci/hotplug/ibmphp_ebda.c  | 8 ++++++--
 drivers/pci/hotplug/sgi_hotplug.c  | 3 ++-
 drivers/pci/hotplug/shpchp_sysfs.c | 2 +-
 5 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/pci/hotplug-pci.c b/drivers/pci/hotplug-pci.c
index 6258dc2..18533ed 100644
--- a/drivers/pci/hotplug-pci.c
+++ b/drivers/pci/hotplug-pci.c
@@ -11,7 +11,7 @@ int __ref pci_hp_add_bridge(struct pci_dev *dev)
 	int end = parent->busn_res.end;
 
 	for (busnr = start; busnr <= end; busnr++) {
-		if (!pci_find_bus(pci_domain_nr(parent), busnr))
+		if (!pci_bus_exists(pci_domain_nr(parent), busnr))
 			break;
 	}
 	if (busnr-- > end) {
diff --git a/drivers/pci/hotplug/ibmphp_core.c b/drivers/pci/hotplug/ibmphp_core.c
index cbd72d8..fb47695 100644
--- a/drivers/pci/hotplug/ibmphp_core.c
+++ b/drivers/pci/hotplug/ibmphp_core.c
@@ -739,7 +739,7 @@ static u8 bus_structure_fixup(u8 busno)
 	struct pci_dev *dev;
 	u16 l;
 
-	if (pci_find_bus(0, busno) || !(ibmphp_find_same_bus_num(busno)))
+	if (pci_bus_exists(0, busno) || !(ibmphp_find_same_bus_num(busno)))
 		return 1;
 
 	bus = kmalloc(sizeof(*bus), GFP_KERNEL);
@@ -787,7 +787,7 @@ static int ibm_configure_device(struct pci_func *func)
 				PCI_DEVFN(func->device, func->function));
 
 	if (func->dev == NULL) {
-		struct pci_bus *bus = pci_find_bus(0, func->busno);
+		struct pci_bus *bus = pci_get_bus(0, func->busno);
 		if (!bus)
 			return 0;
 
@@ -795,6 +795,7 @@ static int ibm_configure_device(struct pci_func *func)
 				PCI_DEVFN(func->device, func->function));
 		if (num)
 			pci_bus_add_devices(bus);
+		pci_bus_put(bus);
 
 		func->dev = pci_get_bus_and_slot(func->busno,
 				PCI_DEVFN(func->device, func->function));
@@ -1315,13 +1316,14 @@ static int __init ibmphp_init(void)
 		goto exit;
 	}
 
-	bus = pci_find_bus(0, 0);
+	bus = pci_get_bus(0, 0);
 	if (!bus) {
 		err("Can't find the root pci bus, can not continue\n");
 		rc = -ENODEV;
 		goto error;
 	}
 	memcpy(ibmphp_pci_bus, bus, sizeof(*ibmphp_pci_bus));
+	pci_bus_put(bus);
 
 	ibmphp_debug = debug;
 
diff --git a/drivers/pci/hotplug/ibmphp_ebda.c b/drivers/pci/hotplug/ibmphp_ebda.c
index 9df78bc..e17f271 100644
--- a/drivers/pci/hotplug/ibmphp_ebda.c
+++ b/drivers/pci/hotplug/ibmphp_ebda.c
@@ -978,9 +978,13 @@ static int __init ebda_rsrc_controller (void)
 	}			/* each hpc  */
 
 	list_for_each_entry(tmp_slot, &ibmphp_slot_head, ibm_slot_list) {
+		struct pci_bus *bus = pci_get_bus(0, tmp_slot->bus);
+
+		BUG_ON(!bus);
 		snprintf(name, SLOT_NAME_SIZE, "%s", create_file_name(tmp_slot));
-		pci_hp_register(tmp_slot->hotplug_slot,
-			pci_find_bus(0, tmp_slot->bus), tmp_slot->device, name);
+		pci_hp_register(tmp_slot->hotplug_slot, bus, tmp_slot->device,
+				name);
+		pci_bus_put(bus);
 	}
 
 	print_ebda_hpc ();
diff --git a/drivers/pci/hotplug/sgi_hotplug.c b/drivers/pci/hotplug/sgi_hotplug.c
index b2781df..5c69bda 100644
--- a/drivers/pci/hotplug/sgi_hotplug.c
+++ b/drivers/pci/hotplug/sgi_hotplug.c
@@ -684,7 +684,7 @@ static int __init sn_pci_hotplug_init(void)
 
 	INIT_LIST_HEAD(&sn_hp_list);
 
-	while ((pci_bus = pci_find_next_bus(pci_bus))) {
+	for_each_pci_root_bus(pci_bus) {
 		if (!pci_bus->sysdata)
 			continue;
 
@@ -703,6 +703,7 @@ static int __init sn_pci_hotplug_init(void)
 			break;
 		}
 	}
+	pci_bus_put(pci_bus);
 
 	return registered == 1 ? 0 : -ENODEV;
 }
diff --git a/drivers/pci/hotplug/shpchp_sysfs.c b/drivers/pci/hotplug/shpchp_sysfs.c
index e8c31fe..e7a5dd2 100644
--- a/drivers/pci/hotplug/shpchp_sysfs.c
+++ b/drivers/pci/hotplug/shpchp_sysfs.c
@@ -74,7 +74,7 @@ static ssize_t show_ctrl (struct device *dev, struct device_attribute *attr, cha
 	}
 	out += sprintf(out, "Free resources: bus numbers\n");
 	for (busnr = bus->busn_res.start; busnr <= bus->busn_res.end; busnr++) {
-		if (!pci_find_bus(pci_domain_nr(bus), busnr))
+		if (!pci_bus_exists(pci_domain_nr(bus), busnr))
 			break;
 	}
 	if (busnr < bus->busn_res.end)
-- 
1.8.1.2