We have partial hot-add support in acpiphp driver, and it is confusing.

Move host bridge hot-add support to pci_root.c, and keep acpiphp simple,
also add hot-remove support in pci_root.c.

How to test it: if sci_emu patch is applied,

Find out root bus number to acpi root name mapping from dmesg or /sys

  echo "\_SB.PCIB 3" > /sys/kernel/debug/acpi/sci_notify
to remove root bus

  echo "\_SB.PCIB 1" > /sys/kernel/debug/acpi/sci_notify
to add back root bus

-v2: put back pci_root_hp change in one patch
-v3: add pcibios_resource_survey_bus() calling
-v4: remove not needed code with remove_bridge
-v5: put back support for acpiphp support for slots just on root bus.
-v6: change some functions to *_p2p_* to make it more clean.
-v7: split hot_added change out.
-v8: Move to pci_root.c instead of adding another file requested by Bjorn.
-v9: Fold three following patches into this one for easy review:
        a: Add missing hot_remove support for root device.
        b: Tang Chen noticed that hotplug through container will not update
           acpi_root_bridge list. After closely checking, we don't need
           that for struct for tracking and could use acpi_pci_root directly.
        c: Tang Chen found handle_root_bridge_removal is very similiar to
           acpi_bus_hot_remove_device().  Change to handle_root_bridge_removal
           to use acpi_bus_hot_remove_device.

Signed-off-by: Yinghai Lu <ying...@kernel.org>
---
 drivers/acpi/pci_root.c            |  139 ++++++++++++++++++++++++++++++++++++
 drivers/pci/hotplug/acpiphp_glue.c |   59 ++++-----------
 2 files changed, 154 insertions(+), 44 deletions(-)

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index bf5108a..3ce5d80 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -655,3 +655,142 @@ int __init acpi_pci_root_init(void)
 
        return 0;
 }
+
+/* Support root bridge hotplug */
+
+static void handle_root_bridge_insertion(acpi_handle handle)
+{
+       struct acpi_device *device, *pdevice;
+       acpi_handle phandle;
+       int ret_val;
+
+       acpi_get_parent(handle, &phandle);
+       if (acpi_bus_get_device(phandle, &pdevice)) {
+               printk(KERN_DEBUG "no parent device, assuming NULL\n");
+               pdevice = NULL;
+       }
+       if (!acpi_bus_get_device(handle, &device)) {
+               /* check if  pci root_bus is removed */
+               struct acpi_pci_root *root = acpi_driver_data(device);
+               if (pci_find_bus(root->segment, root->secondary.start))
+                       return;
+
+               printk(KERN_DEBUG "bus exists... trim\n");
+               /* this shouldn't be in here, so remove
+                * the bus then re-add it...
+                */
+               ret_val = acpi_bus_trim(device);
+               printk(KERN_DEBUG "acpi_bus_trim return %x\n", ret_val);
+       }
+       if (acpi_bus_add(handle))
+               printk(KERN_ERR "cannot add bridge to acpi list\n");
+}
+
+static void handle_root_bridge_removal(struct acpi_device *device)
+{
+       struct acpi_eject_event *ej_event;
+
+       ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
+       if (!ej_event)
+               return;
+
+       ej_event->device = device;
+       ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
+
+       acpi_bus_hot_remove_device(ej_event);
+}
+
+static void _handle_hotplug_event_root(struct work_struct *work)
+{
+       struct acpi_pci_root *root;
+       char objname[64];
+       struct acpi_buffer buffer = { .length = sizeof(objname),
+                                     .pointer = objname };
+       struct acpi_hp_work *hp_work;
+       acpi_handle handle;
+       u32 type;
+
+       hp_work = container_of(work, struct acpi_hp_work, work);
+       handle = hp_work->handle;
+       type = hp_work->type;
+
+       root = acpi_pci_find_root(handle);
+
+       acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+
+       switch (type) {
+       case ACPI_NOTIFY_BUS_CHECK:
+               /* bus enumerate */
+               printk(KERN_DEBUG "%s: Bus check notify on %s\n", __func__,
+                                objname);
+               if (!root)
+                       handle_root_bridge_insertion(handle);
+
+               break;
+
+       case ACPI_NOTIFY_DEVICE_CHECK:
+               /* device check */
+               printk(KERN_DEBUG "%s: Device check notify on %s\n", __func__,
+                                objname);
+               if (!root)
+                       handle_root_bridge_insertion(handle);
+               break;
+
+       case ACPI_NOTIFY_EJECT_REQUEST:
+               /* request device eject */
+               printk(KERN_DEBUG "%s: Device eject notify on %s\n", __func__,
+                                objname);
+               if (root)
+                       handle_root_bridge_removal(root->device);
+               break;
+       default:
+               printk(KERN_WARNING "notify_handler: unknown event type 0x%x 
for %s\n",
+                                type, objname);
+               break;
+       }
+
+       kfree(hp_work); /* allocated in handle_hotplug_event_bridge */
+}
+
+static void handle_hotplug_event_root(acpi_handle handle, u32 type,
+                                       void *context)
+{
+       alloc_acpi_hp_work(handle, type, context,
+                               _handle_hotplug_event_root);
+}
+
+static acpi_status __init
+find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+       char objname[64];
+       struct acpi_buffer buffer = { .length = sizeof(objname),
+                                     .pointer = objname };
+       int *count = (int *)context;
+
+       if (!acpi_is_root_bridge(handle))
+               return AE_OK;
+
+       (*count)++;
+
+       acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+
+       acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+                               handle_hotplug_event_root, NULL);
+       printk(KERN_DEBUG "acpi root: %s notify handler installed\n", objname);
+
+       return AE_OK;
+}
+
+static int __init acpi_pci_root_hp_init(void)
+{
+       int num = 0;
+
+       acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+               ACPI_UINT32_MAX, find_root_bridges, NULL, &num, NULL);
+
+       printk(KERN_DEBUG "Found %d acpi root devices\n", num);
+
+       return 0;
+}
+
+subsys_initcall(acpi_pci_root_hp_init);
diff --git a/drivers/pci/hotplug/acpiphp_glue.c 
b/drivers/pci/hotplug/acpiphp_glue.c
index 55e03b6..45917a5 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -543,10 +543,13 @@ static void cleanup_bridge(struct acpiphp_bridge *bridge)
        acpi_status status;
        acpi_handle handle = bridge->handle;
 
-       status = acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+       if (bridge->type != BRIDGE_TYPE_HOST) {
+               status = acpi_remove_notify_handler(handle,
+                                           ACPI_SYSTEM_NOTIFY,
                                            handle_hotplug_event_bridge);
-       if (ACPI_FAILURE(status))
-               err("failed to remove notify handler\n");
+               if (ACPI_FAILURE(status))
+                       err("failed to remove notify handler\n");
+       }
 
        if ((bridge->type != BRIDGE_TYPE_HOST) &&
            ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func)) {
@@ -630,9 +633,6 @@ static void remove_bridge(struct acpi_pci_root *root)
        bridge = acpiphp_handle_to_bridge(handle);
        if (bridge)
                cleanup_bridge(bridge);
-       else
-               acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
-                                          handle_hotplug_event_bridge);
 }
 
 static int power_on_slot(struct acpiphp_slot *slot)
@@ -1123,18 +1123,12 @@ static void acpiphp_sanitize_bus(struct pci_bus *bus)
 }
 
 /* Program resources in newly inserted bridge */
-static int acpiphp_configure_bridge (acpi_handle handle)
+static int acpiphp_configure_p2p_bridge(acpi_handle handle)
 {
-       struct pci_bus *bus;
+       struct pci_dev *pdev = acpi_get_pci_dev(handle);
+       struct pci_bus *bus = pdev->subordinate;
 
-       if (acpi_is_root_bridge(handle)) {
-               struct acpi_pci_root *root = acpi_pci_find_root(handle);
-               bus = root->bus;
-       } else {
-               struct pci_dev *pdev = acpi_get_pci_dev(handle);
-               bus = pdev->subordinate;
-               pci_dev_put(pdev);
-       }
+       pci_dev_put(pdev);
 
        pci_bus_size_bridges(bus);
        pci_bus_assign_resources(bus);
@@ -1144,7 +1138,7 @@ static int acpiphp_configure_bridge (acpi_handle handle)
        return 0;
 }
 
-static void handle_bridge_insertion(acpi_handle handle, u32 type)
+static void handle_p2p_bridge_insertion(acpi_handle handle, u32 type)
 {
        struct acpi_device *device;
 
@@ -1162,8 +1156,8 @@ static void handle_bridge_insertion(acpi_handle handle, 
u32 type)
                err("ACPI device object missing\n");
                return;
        }
-       if (!acpiphp_configure_bridge(handle))
-               add_bridge(handle);
+       if (!acpiphp_configure_p2p_bridge(handle))
+               add_p2p_bridge(handle);
        else
                err("cannot configure and start bridge\n");
 
@@ -1221,7 +1215,7 @@ static void _handle_hotplug_event_bridge(struct 
work_struct *work)
 
        if (acpi_bus_get_device(handle, &device)) {
                /* This bridge must have just been physically inserted */
-               handle_bridge_insertion(handle, type);
+               handle_p2p_bridge_insertion(handle, type);
                goto out;
        }
 
@@ -1396,21 +1390,6 @@ static void handle_hotplug_event_func(acpi_handle 
handle, u32 type,
        alloc_acpi_hp_work(handle, type, context, _handle_hotplug_event_func);
 }
 
-static acpi_status
-find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
-{
-       int *count = (int *)context;
-
-       if (!acpi_is_root_bridge(handle))
-               return AE_OK;
-
-       (*count)++;
-       acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
-                                   handle_hotplug_event_bridge, NULL);
-
-       return AE_OK ;
-}
-
 static struct acpi_pci_driver acpi_pci_hp_driver = {
        .add =          add_bridge,
        .remove =       remove_bridge,
@@ -1421,15 +1400,7 @@ static struct acpi_pci_driver acpi_pci_hp_driver = {
  */
 int __init acpiphp_glue_init(void)
 {
-       int num = 0;
-
-       acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
-                       ACPI_UINT32_MAX, find_root_bridges, NULL, &num, NULL);
-
-       if (num <= 0)
-               return -1;
-       else
-               acpi_pci_register_driver(&acpi_pci_hp_driver);
+       acpi_pci_register_driver(&acpi_pci_hp_driver);
 
        return 0;
 }
-- 
1.7.10.4

--
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/

Reply via email to