Now we have pci_root_buses list, and there is lots of iteration with
list_of_each of it, that is not safe after we add pci root bus hotplug
support after booting stage.
Also pci_find_next_bus is pretty misleading name, and it is only finding
next root bus instead of regular pci bus.
Add pci_get_next_host_bridge and use bus_find_device in driver core to
iterate host bridge and the same time get root bus.
In folllowing patches will replace searching root bus with searching
host_bridge.
after using with that host-bridge, will need to call put device to release
reference if break early from the loop.
After those replacing, we even could kill pci_root_buses list.
-v2: fixes compiling error when CONFIG_PCI is not defined that Fengguang Wu
found.
Signed-off-by: Yinghai Lu <yinghai at kernel.org>
Cc: Mauro Carvalho Chehab <mchehab at redhat.com>
Cc: Doug Thompson <dougthompson at xmission.com>
Cc: linux-edac at vger.kernel.org
Cc: x86 at kernel.org
Cc: David Airlie <airlied at linux.ie>
Cc: dri-devel at lists.freedesktop.org
Cc: "David S. Miller" <davem at davemloft.net>
Cc: sparclinux at vger.kernel.org
Cc: Tony Luck <tony.luck at intel.com>
Cc: Fenghua Yu <fenghua.yu at intel.com>
Cc: linux-ia64 at vger.kernel.org
Cc: linux-altix at sgi.com
Cc: Richard Henderson <rth at twiddle.net>
Cc: Ivan Kokshaysky <ink at jurassic.park.msu.ru>
Cc: Matt Turner <mattst88 at gmail.com>
Cc: linux-alpha at vger.kernel.org
Cc: Russell King <linux at arm.linux.org.uk>
Cc: linux-arm-kernel at lists.infradead.org
Cc: David Howells <dhowells at redhat.com>
Cc: Michal Simek <monstr at monstr.eu>
Cc: microblaze-uclinux at itee.uq.edu.au
Cc: Koichi Yasutake <yasutake.koichi at jp.panasonic.com>
Cc: linux-am33-list at redhat.com
Cc: Benjamin Herrenschmidt <benh at kernel.crashing.org>
Cc: Paul Mackerras <paulus at samba.org>
Cc: linuxppc-dev at lists.ozlabs.org
---
drivers/pci/search.c | 24 ++++++++++++++++++++++++
include/linux/pci.h | 9 +++++++++
2 files changed, 33 insertions(+)
diff --git a/drivers/pci/search.c b/drivers/pci/search.c
index d0627fa..db0c3a9 100644
--- a/drivers/pci/search.c
+++ b/drivers/pci/search.c
@@ -178,6 +178,30 @@ struct pci_dev *pci_get_domain_bus_and_slot(int domain,
unsigned int bus,
}
EXPORT_SYMBOL(pci_get_domain_bus_and_slot);
+static int match_pci_host_bridge(struct device *dev, void *data)
+{
+ return 1;
+}
+
+struct pci_host_bridge *pci_get_next_host_bridge(struct pci_host_bridge *from)
+{
+ struct device *dev;
+ struct device *dev_start = NULL;
+ struct pci_host_bridge *bridge = NULL;
+
+ WARN_ON(in_interrupt());
+ if (from)
+ dev_start = &from->dev;
+ dev = bus_find_device(&pci_host_bridge_bus_type, dev_start, NULL,
+ match_pci_host_bridge);
+ if (dev)
+ bridge = to_pci_host_bridge(dev);
+ if (from)
+ put_device(&from->dev);
+ return bridge;
+}
+EXPORT_SYMBOL_GPL(pci_get_next_host_bridge);
+
static int match_pci_dev_by_id(struct device *dev, void *data)
{
struct pci_dev *pdev = to_pci_dev(dev);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 9da06ec..67879cb 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -375,6 +375,8 @@ struct pci_host_bridge {
};
#define to_pci_host_bridge(n) container_of(n, struct pci_host_bridge,
dev)
+#define for_each_pci_host_bridge(d) while ((d = pci_get_next_host_bridge(d))
!= NULL)
+
void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
void (*release_fn)(struct pci_host_bridge *),
void *release_data);
@@ -763,6 +765,7 @@ int pci_find_ht_capability(struct pci_dev *dev, int ht_cap);
int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap);
struct pci_bus *pci_find_next_bus(const struct pci_bus *from);
+struct pci_host_bridge *pci_get_next_host_bridge(struct pci_host_bridge *from);
struct pci_dev *pci_get_device(unsigned int vendor, unsigned int device,
struct pci_dev *from);
struct pci_dev *pci_get_subsys(unsigned int vendor, unsigned int device,
@@ -1418,6 +1421,12 @@ static inline int pci_domain_nr(struct pci_bus *bus)
static inline struct pci_dev *pci_dev_get(struct pci_dev *dev)
{ return NULL; }
+static inline struct pci_host_bridge *pci_get_next_host_bridge(
+ struct pci_host_bridge *host_bridge)
+{
+ return NULL;
+}
+
#define dev_is_pci(d) (false)
#define dev_is_pf(d) (false)
#define dev_num_vf(d) (0)
--
1.7.10.4
