Patchwork [ACPIHP,part2,09/13] ACPIHP: configure/unconfigure system devices attached to a hotplug slot

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Submitter Jiang Liu
Date Nov. 4, 2012, 12:50 p.m.
Message ID <1352033415-5606-10-git-send-email-jiang.liu@huawei.com>
Download mbox | patch
Permalink /patch/197035/
State Not Applicable
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Comments

Jiang Liu - Nov. 4, 2012, 12:50 p.m.
This patch implements interfaces to configure/unconfigure system devices
attached to a hotplug slot. Configuring is to add system devices into
running system and put then into use, unconfiguring is to remove system
devices from running system.

To support better error recover and cancellation, device configuration
operations are splitted into three steps and unconfiguration operations
are splitted into six steps as below:
CONFIGURE
 1) pre_configure(): optional step to pre-allocate special resources
 2) configure(): allocate required resources
 3) pos_configure(): add devices into system or rollback
UNCONFIGURE
 1) pre_release(): optional step to mark device going to be removed/busy
 2) release(): reclaim device from running system
 3) post_release(): rollback if cancelled by user or error happened
 4) pre_unconfigure(): optional step to solve possible dependency issue
 5) unconfigure(): remove devices from running system
 6) post_unconfigure(): free resources used by devices

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Hanjun Guo <guohanjun@huawei.com>
---
 drivers/acpi/hotplug/Makefile     |    1 +
 drivers/acpi/hotplug/acpihp_drv.h |    4 +
 drivers/acpi/hotplug/configure.c  |  341 +++++++++++++++++++++++++++++++++++++
 3 files changed, 346 insertions(+)
 create mode 100644 drivers/acpi/hotplug/configure.c

Patch

diff --git a/drivers/acpi/hotplug/Makefile b/drivers/acpi/hotplug/Makefile
index f72f2c3..6cb6aa1 100644
--- a/drivers/acpi/hotplug/Makefile
+++ b/drivers/acpi/hotplug/Makefile
@@ -14,3 +14,4 @@  obj-$(CONFIG_ACPI_HOTPLUG_DRIVER)		+= acpihp_drv.o
 acpihp_drv-y					= drv_main.o
 acpihp_drv-y					+= dependency.o
 acpihp_drv-y					+= cancel.o
+acpihp_drv-y					+= configure.o
diff --git a/drivers/acpi/hotplug/acpihp_drv.h b/drivers/acpi/hotplug/acpihp_drv.h
index dd8ea92..aa239f6 100644
--- a/drivers/acpi/hotplug/acpihp_drv.h
+++ b/drivers/acpi/hotplug/acpihp_drv.h
@@ -58,6 +58,7 @@  struct acpihp_slot_dependency {
 	struct list_head		node;
 	struct acpihp_slot		*slot;
 	u32				opcodes;
+	u32				execute_stages;
 };
 
 void acpihp_drv_get_data(struct acpihp_slot *slot,
@@ -81,4 +82,7 @@  void acpihp_drv_cancel_fini(struct list_head *list);
 int acpihp_drv_cancel_start(struct list_head *list);
 int acpihp_drv_cancel_wait(struct list_head *list);
 
+int acpihp_drv_configure(struct list_head *list);
+int acpihp_drv_unconfigure(struct list_head *list);
+
 #endif	/* __ACPIHP_DRV_H__ */
diff --git a/drivers/acpi/hotplug/configure.c b/drivers/acpi/hotplug/configure.c
new file mode 100644
index 0000000..3209d14b
--- /dev/null
+++ b/drivers/acpi/hotplug/configure.c
@@ -0,0 +1,341 @@ 
+/*
+ * Copyright (C) 2012 Huawei Tech. Co., Ltd.
+ * Copyright (C) 2012 Jiang Liu <jiang.liu@huawei.com>
+ * Copyright (C) 2012 Hanjun Guo <guohanjun@huawei.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_hotplug.h>
+#include "acpihp_drv.h"
+
+enum config_op_code {
+	DRV_OP_PRE_CONFIGURE,
+	DRV_OP_CONFIGURE,
+	DRV_OP_POST_CONFIGURE,
+	DRV_OP_PRE_RELEASE,
+	DRV_OP_RELEASE,
+	DRV_OP_POST_RELEASE,
+	DRV_OP_PRE_UNCONFIGURE,
+	DRV_OP_UNCONFIGURE,
+	DRV_OP_POST_UNCONFIGURE
+};
+
+/* All devices will be configured in following order. */
+static enum acpihp_dev_type acpihp_drv_dev_types[] = {
+	ACPIHP_DEV_TYPE_CONTAINER,
+	ACPIHP_DEV_TYPE_MEM,
+	ACPIHP_DEV_TYPE_CPU,
+	ACPIHP_DEV_TYPE_HOST_BRIDGE,
+};
+
+/* All devices will be unconfigured in following order. */
+static enum acpihp_dev_type acpihp_drv_dev_types_reverse[] = {
+	ACPIHP_DEV_TYPE_HOST_BRIDGE,
+	ACPIHP_DEV_TYPE_CPU,
+	ACPIHP_DEV_TYPE_MEM,
+	ACPIHP_DEV_TYPE_CONTAINER,
+};
+
+static void acpihp_drv_update_dev_state(struct acpihp_dev_node *dev,
+					enum acpihp_dev_state state)
+{
+	BUG_ON(state <= DEVICE_STATE_UNKOWN || state >= DEVICE_STATE_MAX);
+	dev->state = state;
+}
+
+static int acpihp_drv_invoke_method(enum config_op_code  opcode,
+				    struct acpihp_slot *slot,
+				    struct acpi_device *dev, int post)
+{
+	struct acpihp_slot_drv *drv_data;
+
+	acpihp_drv_get_data(slot, &drv_data);
+
+	switch (opcode) {
+	case DRV_OP_PRE_CONFIGURE:
+		if (drv_data->cancel_ctx.check_cancel(&drv_data->cancel_ctx))
+			return -ECANCELED;
+		return acpihp_dev_pre_configure(dev, &drv_data->cancel_ctx);
+	case DRV_OP_CONFIGURE:
+		if (drv_data->cancel_ctx.check_cancel(&drv_data->cancel_ctx))
+			return -ECANCELED;
+		return acpihp_dev_configure(dev, &drv_data->cancel_ctx);
+	case DRV_OP_POST_CONFIGURE:
+		return acpihp_dev_post_configure(dev, post);
+	case DRV_OP_PRE_RELEASE:
+		if (drv_data->cancel_ctx.check_cancel(&drv_data->cancel_ctx))
+			return -ECANCELED;
+		return acpihp_dev_pre_release(dev, &drv_data->cancel_ctx);
+	case DRV_OP_RELEASE:
+		if (drv_data->cancel_ctx.check_cancel(&drv_data->cancel_ctx))
+			return -ECANCELED;
+		return acpihp_dev_release(dev, &drv_data->cancel_ctx);
+	case DRV_OP_POST_RELEASE:
+		return acpihp_dev_post_release(dev, post);
+	case DRV_OP_PRE_UNCONFIGURE:
+		return acpihp_dev_pre_unconfigure(dev);
+	case DRV_OP_UNCONFIGURE:
+		return acpihp_dev_unconfigure(dev);
+	case DRV_OP_POST_UNCONFIGURE:
+		return acpihp_dev_post_unconfigure(dev);
+	default:
+		BUG_ON(opcode);
+		return -ENOSYS;
+	}
+}
+
+static int acpihp_drv_call_method(enum config_op_code opcode,
+				  struct acpihp_slot *slot,
+				  enum acpihp_dev_type type,
+				  enum acpihp_dev_state state)
+{
+	int result = 0;
+	struct klist_iter iter;
+	struct klist_node *ip;
+	struct acpihp_dev_node *np;
+	struct acpi_device *acpi_dev;
+
+	klist_iter_init(&slot->dev_lists[type], &iter);
+	while ((ip = klist_next(&iter)) != NULL) {
+		np = container_of(ip, struct acpihp_dev_node, node);
+		acpi_dev = container_of(np->dev, struct acpi_device, dev);
+		result = acpihp_drv_invoke_method(opcode, slot, acpi_dev, 0);
+		if (result)
+			break;
+		acpihp_drv_update_dev_state(np, state);
+	}
+	klist_iter_exit(&iter);
+
+	return result;
+}
+
+static int acpihp_drv_call_method_post(enum config_op_code opcode,
+				       struct acpihp_slot *slot,
+				       enum acpihp_dev_type type,
+				       enum acpihp_dev_state state,
+				       enum acpihp_dev_post_cmd post)
+{
+	int retval = 0;
+	int result;
+	struct klist_iter iter;
+	struct klist_node *ip;
+	struct acpihp_dev_node *np;
+	struct acpi_device *acpi_dev;
+
+	klist_iter_init(&slot->dev_lists[type], &iter);
+	while ((ip = klist_next(&iter)) != NULL) {
+		np = container_of(ip, struct acpihp_dev_node, node);
+		acpi_dev = container_of(np->dev, struct acpi_device, dev);
+		if (np->state == state && post == ACPIHP_DEV_POST_CMD_ROLLBACK)
+			continue;
+
+		result = acpihp_drv_invoke_method(opcode, slot, acpi_dev, post);
+		if (result)
+			retval = -EIO;
+		else if (post == ACPIHP_DEV_POST_CMD_ROLLBACK)
+			acpihp_drv_update_dev_state(np, state);
+	}
+	klist_iter_exit(&iter);
+
+	return retval;
+}
+
+static int acpihp_drv_walk_devs(struct list_head *slot_list,
+				enum config_op_code opcode,
+				enum acpihp_dev_state state,
+				bool reverse)
+{
+	int i, retval = 0;
+	enum acpihp_dev_type *tp;
+	struct acpihp_slot_dependency *dep;
+	int count = ARRAY_SIZE(acpihp_drv_dev_types);
+
+	tp = reverse ? acpihp_drv_dev_types_reverse : acpihp_drv_dev_types;
+	for (i = 0; i < count; i++)
+		list_for_each_entry(dep, slot_list, node) {
+			retval = acpihp_drv_call_method(opcode, dep->slot,
+							tp[i], state);
+			if (retval)
+				return retval;
+			dep->execute_stages |= 1 << opcode;
+		}
+
+	return 0;
+}
+
+static void acpihp_drv_walk_devs_post(struct list_head *slot_list,
+				      enum config_op_code opcode,
+				      enum acpihp_dev_state state,
+				      enum acpihp_dev_post_cmd post,
+				      bool reverse)
+{
+	int i;
+	enum acpihp_dev_type *tp;
+	struct acpihp_slot_dependency *dep;
+	int count = ARRAY_SIZE(acpihp_drv_dev_types);
+
+	tp = reverse ? acpihp_drv_dev_types_reverse : acpihp_drv_dev_types;
+	for (i = 0; i < count; i++)
+		list_for_each_entry(dep, slot_list, node) {
+			if (!dep->execute_stages)
+				continue;
+			if (acpihp_drv_call_method_post(opcode, dep->slot,
+							tp[i], state, post))
+				ACPIHP_SLOT_WARN(dep->slot,
+					"fails to commit or rollback.\n");
+		}
+}
+
+static void acpihp_drv_sync_cancel(struct list_head *list, int result)
+{
+	int cancel;
+	struct acpihp_slot_dependency *dep;
+
+	if (!result)
+		cancel = ACPIHP_DRV_CANCEL_MISSED;
+	else if (result == -ECANCELED)
+		cancel = ACPIHP_DRV_CANCEL_OK;
+	else
+		cancel = ACPIHP_DRV_CANCEL_FAILED;
+
+	list_for_each_entry(dep, list, node) {
+		acpihp_drv_cancel_notify(dep->slot, cancel);
+		acpihp_drv_update_slot_state(dep->slot);
+	}
+}
+
+/*
+ * To support better error recover and cancellation, configure operations
+ * are splitted into three steps:
+ * 1) pre_configure(): optional step to setup special resources
+ * 2) configure(): allocate required resources and initialize device
+ * 3) post_configure(): add device into system or rollback
+ */
+int acpihp_drv_configure(struct list_head *list)
+{
+	int result;
+	struct list_head head;
+	struct acpihp_slot_dependency *dep;
+	enum acpihp_dev_post_cmd post = ACPIHP_DEV_POST_CMD_COMMIT;
+
+	result = acpihp_drv_filter_dependency_list(list, &head,
+						   ACPIHP_DRV_CMD_CONFIGURE);
+	if (result) {
+		ACPIHP_DEBUG("fails to filter dependency list.\n");
+		return -ENOMEM;
+	}
+
+	list_for_each_entry(dep, &head, node)
+		acpihp_slot_change_state(dep->slot,
+					 ACPIHP_SLOT_STATE_CONFIGURING);
+
+	result = acpihp_drv_walk_devs(&head, DRV_OP_PRE_CONFIGURE,
+				      DEVICE_STATE_PRE_CONFIGURE, false);
+	if (!result)
+		result = acpihp_drv_walk_devs(&head, DRV_OP_CONFIGURE,
+					      DEVICE_STATE_CONFIGURED, false);
+	if (result)
+		post = ACPIHP_DEV_POST_CMD_ROLLBACK;
+	acpihp_drv_walk_devs_post(&head, DRV_OP_POST_CONFIGURE,
+				  DEVICE_STATE_CONNECTED, post, false);
+
+	list_for_each_entry(dep, &head, node)
+		acpihp_drv_update_slot_state(dep->slot);
+	acpihp_drv_sync_cancel(&head, result);
+	acpihp_drv_destroy_dependency_list(&head);
+
+	return result;
+}
+
+static int acpihp_drv_release(struct list_head *list)
+{
+	int result;
+	enum acpihp_dev_post_cmd post = ACPIHP_DEV_POST_CMD_COMMIT;
+
+	result = acpihp_drv_walk_devs(list, DRV_OP_PRE_RELEASE,
+				      DEVICE_STATE_PRE_RELEASE, true);
+	if (!result)
+		result = acpihp_drv_walk_devs(list, DRV_OP_RELEASE,
+					      DEVICE_STATE_RELEASED, true);
+	if (result)
+		post = ACPIHP_DEV_POST_CMD_ROLLBACK;
+	acpihp_drv_walk_devs_post(list, DRV_OP_POST_RELEASE,
+				  DEVICE_STATE_CONFIGURED, post, true);
+	acpihp_drv_sync_cancel(list, result);
+
+	return result;
+}
+
+static void __acpihp_drv_unconfigure(struct list_head *list)
+{
+	int result;
+
+	result = acpihp_drv_walk_devs(list, DRV_OP_PRE_UNCONFIGURE,
+				      DEVICE_STATE_PRE_UNCONFIGURE, true);
+	BUG_ON(result);
+	result = acpihp_drv_walk_devs(list, DRV_OP_UNCONFIGURE,
+				      DEVICE_STATE_CONNECTED, true);
+	BUG_ON(result);
+	result = acpihp_drv_walk_devs(list, DRV_OP_POST_UNCONFIGURE,
+				      DEVICE_STATE_CONNECTED, true);
+	BUG_ON(result);
+}
+
+/*
+ * To support better error recover and cancellation, unconfigure operations
+ * are splitted into three steps:
+ * 1) pre_release(): optional
+ * 2) release(): reclaim devices from system
+ * 3) post_release(): rollback if cancelled or failed to reclaim devices
+ * 4) pre_unconfigure(): optional
+ * 5) unconfigure(): remove devices from system
+ * 6) post_unconfigure(): free resources used by devices
+ */
+int acpihp_drv_unconfigure(struct list_head *list)
+{
+	int result;
+	struct list_head head;
+	struct acpihp_slot_dependency *dep;
+
+	result = acpihp_drv_filter_dependency_list(list, &head,
+						   ACPIHP_DRV_CMD_UNCONFIGURE);
+	if (result) {
+		ACPIHP_DEBUG("fails to filter dependency list.\n");
+		return -ENOMEM;
+	}
+
+	list_for_each_entry(dep, &head, node)
+		acpihp_slot_change_state(dep->slot,
+					 ACPIHP_SLOT_STATE_UNCONFIGURING);
+
+	result = acpihp_drv_release(&head);
+	if (!result)
+		__acpihp_drv_unconfigure(&head);
+
+	list_for_each_entry(dep, &head, node)
+		acpihp_drv_update_slot_state(dep->slot);
+
+	acpihp_drv_destroy_dependency_list(&head);
+
+	return result;
+}