We have a pci_walk_bus() interface, but it's exceptionally cumbersome
for the callback function to figure out if the device is relevant if
the caller is trying to walk all the devices in or below a slot. Add
a variant to walk only slot devices.
Signed-off-by: Alex Williamson <alex.william...@redhat.com>
---
This allows me to use pci_walk_bus() and pci_walk_slot() instead of
rolling my own for iterating devices for bus/slot reset. Please
consider for 3.12 to go with the rest of the bus/slot infrastructure.
drivers/pci/bus.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/pci.h | 2 ++
2 files changed, 58 insertions(+)
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index b1ff02a..316579a 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -283,6 +283,62 @@ void pci_walk_bus(struct pci_bus *top, int (*cb)(struct
pci_dev *, void *),
}
EXPORT_SYMBOL_GPL(pci_walk_bus);
+/** pci_walk_slot - walk devices in/under slot, calling callback.
+ * @slot slot whose devices should be walked
+ * @cb callback to be called for each device found
+ * @userdata arbitrary pointer to be passed to callback.
+ *
+ * Walk the given slot, including any bridged devices
+ * on buses under this slot. Call the provided callback
+ * on each device found.
+ *
+ * We check the return of @cb each time. If it returns anything
+ * other than 0, we break out.
+ *
+ */
+void pci_walk_slot(struct pci_slot *slot, int (*cb)(struct pci_dev *, void *),
+ void *userdata)
+{
+ struct pci_dev *dev;
+ struct pci_bus *bus;
+ struct list_head *next;
+ int retval;
+
+ bus = slot->bus;
+ down_read(&pci_bus_sem);
+ next = slot->bus->devices.next;
+ for (;;) {
+ if (next == &bus->devices) {
+ /* end of this bus, go up or finish */
+ if (bus == slot->bus)
+ break;
+ next = bus->self->bus_list.next;
+ bus = bus->self->bus;
+ continue;
+ }
+ dev = list_entry(next, struct pci_dev, bus_list);
+
+ /* skip anything on the top level bus not in our slot */
+ if (dev->bus == slot->bus && dev->slot != slot) {
+ next = dev->bus_list.next;
+ continue;
+ }
+
+ if (dev->subordinate) {
+ /* this is a pci-pci bridge, do its devices next */
+ next = dev->subordinate->devices.next;
+ bus = dev->subordinate;
+ } else
+ next = dev->bus_list.next;
+
+ retval = cb(dev, userdata);
+ if (retval)
+ break;
+ }
+ up_read(&pci_bus_sem);
+}
+EXPORT_SYMBOL_GPL(pci_walk_slot);
+
struct pci_bus *pci_bus_get(struct pci_bus *bus)
{
if (bus)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index daf40cd..cbb291b 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1087,6 +1087,8 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev
*dev, int max,
void pci_walk_bus(struct pci_bus *top, int (*cb)(struct pci_dev *, void *),
void *userdata);
+void pci_walk_slot(struct pci_slot *slot, int (*cb)(struct pci_dev *, void *),
+ void *userdata);
int pci_cfg_space_size_ext(struct pci_dev *dev);
int pci_cfg_space_size(struct pci_dev *dev);
unsigned char pci_bus_max_busnr(struct pci_bus *bus);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
