--- /dev/null
+/*
+ * Copyright (C) 2004, 2013 Intel Corporation
+ * Author: Naveen B S <naveen.b.s@intel.com>
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * All rights reserved.
+ *
+ * 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, GOOD TITLE or
+ * NON INFRINGEMENT. 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *
+ * ACPI based HotPlug driver that supports Memory Hotplug
+ * This driver fields notifications from firmware for memory add
+ * and remove operations and alerts the VM of the affected memory
+ * ranges.
+ */
+
+#include <linux/acpi.h>
+#include <linux/memory.h>
+#include <linux/memory_hotplug.h>
+
+#include "internal.h"
+
+#define ACPI_MEMORY_DEVICE_CLASS "memory"
+#define ACPI_MEMORY_DEVICE_HID "PNP0C80"
+#define ACPI_MEMORY_DEVICE_NAME "Hotplug Mem Device"
+
+#define _COMPONENT ACPI_MEMORY_DEVICE_COMPONENT
+
+#undef PREFIX
+#define PREFIX "ACPI:memory_hp:"
+
+ACPI_MODULE_NAME("acpi_memhotplug");
+
+static const struct acpi_device_id memory_device_ids[] = {
+ {ACPI_MEMORY_DEVICE_HID, 0},
+ {"", 0},
+};
+
+#ifdef CONFIG_ACPI_HOTPLUG_MEMORY
+
+/* Memory Device States */
+#define MEMORY_INVALID_STATE 0
+#define MEMORY_POWER_ON_STATE 1
+#define MEMORY_POWER_OFF_STATE 2
+
+static int acpi_memory_device_add(struct acpi_device *device,
+ const struct acpi_device_id *not_used);
+static void acpi_memory_device_remove(struct acpi_device *device);
+
+static struct acpi_scan_handler memory_device_handler = {
+ .ids = memory_device_ids,
+ .attach = acpi_memory_device_add,
+ .detach = acpi_memory_device_remove,
+ .hotplug = {
+ .enabled = true,
+ },
+};
+
+struct acpi_memory_info {
+ struct list_head list;
+ u64 start_addr; /* Memory Range start physical addr */
+ u64 length; /* Memory Range length */
+ unsigned short caching; /* memory cache attribute */
+ unsigned short write_protect; /* memory read/write attribute */
+ unsigned int enabled:1;
+};
+
+struct acpi_memory_device {
+ struct acpi_device * device;
+ unsigned int state; /* State of the memory device */
+ struct list_head res_list;
+};
+
+static acpi_status
+acpi_memory_get_resource(struct acpi_resource *resource, void *context)
+{
+ struct acpi_memory_device *mem_device = context;
+ struct acpi_resource_address64 address64;
+ struct acpi_memory_info *info, *new;
+ acpi_status status;
+
+ status = acpi_resource_to_address64(resource, &address64);
+ if (ACPI_FAILURE(status) ||
+ (address64.resource_type != ACPI_MEMORY_RANGE))
+ return AE_OK;
+
+ list_for_each_entry(info, &mem_device->res_list, list) {
+ /* Can we combine the resource range information? */
+ if ((info->caching == address64.info.mem.caching) &&
+ (info->write_protect == address64.info.mem.write_protect) &&
+ (info->start_addr + info->length == address64.address.minimum)) {
+ info->length += address64.address.address_length;
+ return AE_OK;
+ }
+ }
+
+ new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
+ if (!new)
+ return AE_ERROR;
+
+ INIT_LIST_HEAD(&new->list);
+ new->caching = address64.info.mem.caching;
+ new->write_protect = address64.info.mem.write_protect;
+ new->start_addr = address64.address.minimum;
+ new->length = address64.address.address_length;
+ list_add_tail(&new->list, &mem_device->res_list);
+
+ return AE_OK;
+}
+
+static void
+acpi_memory_free_device_resources(struct acpi_memory_device *mem_device)
+{
+ struct acpi_memory_info *info, *n;
+
+ list_for_each_entry_safe(info, n, &mem_device->res_list, list)
+ kfree(info);
+ INIT_LIST_HEAD(&mem_device->res_list);
+}
+
+static int
+acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
+{
+ acpi_status status;
+
+ if (!list_empty(&mem_device->res_list))
+ return 0;
+
+ status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
+ acpi_memory_get_resource, mem_device);
+ if (ACPI_FAILURE(status)) {
+ acpi_memory_free_device_resources(mem_device);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
+{
+ unsigned long long current_status;
+
+ /* Get device present/absent information from the _STA */
+ if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle,
+ METHOD_NAME__STA, NULL,
+ ¤t_status)))
+ return -ENODEV;
+ /*
+ * Check for device status. Device should be
+ * present/enabled/functioning.
+ */
+ if (!((current_status & ACPI_STA_DEVICE_PRESENT)
+ && (current_status & ACPI_STA_DEVICE_ENABLED)
+ && (current_status & ACPI_STA_DEVICE_FUNCTIONING)))
+ return -ENODEV;
+
+ return 0;
+}
+
+static unsigned long acpi_meminfo_start_pfn(struct acpi_memory_info *info)
+{
+ return PFN_DOWN(info->start_addr);
+}
+
+static unsigned long acpi_meminfo_end_pfn(struct acpi_memory_info *info)
+{
+ return PFN_UP(info->start_addr + info->length-1);
+}
+
+static int acpi_bind_memblk(struct memory_block *mem, void *arg)
+{
+ return acpi_bind_one(&mem->dev, arg);
+}
+
+static int acpi_bind_memory_blocks(struct acpi_memory_info *info,
+ struct acpi_device *adev)
+{
+ return walk_memory_range(acpi_meminfo_start_pfn(info),
+ acpi_meminfo_end_pfn(info), adev,
+ acpi_bind_memblk);
+}
+
+static int acpi_unbind_memblk(struct memory_block *mem, void *arg)
+{
+ acpi_unbind_one(&mem->dev);
+ return 0;
+}
+
+static void acpi_unbind_memory_blocks(struct acpi_memory_info *info)
+{
+ walk_memory_range(acpi_meminfo_start_pfn(info),
+ acpi_meminfo_end_pfn(info), NULL, acpi_unbind_memblk);
+}
+
+static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
+{
+ acpi_handle handle = mem_device->device->handle;
+ int result, num_enabled = 0;
+ struct acpi_memory_info *info;
+ int node;
+
+ node = acpi_get_node(handle);
+ /*
+ * Tell the VM there is more memory here...
+ * Note: Assume that this function returns zero on success
+ * We don't have memory-hot-add rollback function,now.
+ * (i.e. memory-hot-remove function)
+ */
+ list_for_each_entry(info, &mem_device->res_list, list) {
+ if (info->enabled) { /* just sanity check...*/
+ num_enabled++;
+ continue;
+ }
+ /*
+ * If the memory block size is zero, please ignore it.
+ * Don't try to do the following memory hotplug flowchart.
+ */
+ if (!info->length)
+ continue;
+ if (node < 0)
+ node = memory_add_physaddr_to_nid(info->start_addr);
+
+ result = add_memory(node, info->start_addr, info->length);
+
+ /*
+ * If the memory block has been used by the kernel, add_memory()
+ * returns -EEXIST. If add_memory() returns the other error, it
+ * means that this memory block is not used by the kernel.
+ */
+ if (result && result != -EEXIST)
+ continue;
+
+ result = acpi_bind_memory_blocks(info, mem_device->device);
+ if (result) {
+ acpi_unbind_memory_blocks(info);
+ return -ENODEV;
+ }
+
+ info->enabled = 1;
+
+ /*
+ * Add num_enable even if add_memory() returns -EEXIST, so the
+ * device is bound to this driver.
+ */
+ num_enabled++;
+ }
+ if (!num_enabled) {
+ dev_err(&mem_device->device->dev, "add_memory failed\n");
+ mem_device->state = MEMORY_INVALID_STATE;
+ return -EINVAL;
+ }
+ /*
+ * Sometimes the memory device will contain several memory blocks.
+ * When one memory block is hot-added to the system memory, it will
+ * be regarded as a success.
+ * Otherwise if the last memory block can't be hot-added to the system
+ * memory, it will be failure and the memory device can't be bound with
+ * driver.
+ */
+ return 0;
+}
+
+static void acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
+{
+ acpi_handle handle = mem_device->device->handle;
+ struct acpi_memory_info *info, *n;
+ int nid = acpi_get_node(handle);
+
+ list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
+ if (!info->enabled)
+ continue;
+
+ if (nid == NUMA_NO_NODE)
+ nid = memory_add_physaddr_to_nid(info->start_addr);
+
+ acpi_unbind_memory_blocks(info);
+ remove_memory(nid, info->start_addr, info->length);
+ list_del(&info->list);
+ kfree(info);
+ }
+}
+
+static void acpi_memory_device_free(struct acpi_memory_device *mem_device)
+{
+ if (!mem_device)
+ return;
+
+ acpi_memory_free_device_resources(mem_device);
+ mem_device->device->driver_data = NULL;
+ kfree(mem_device);
+}
+
+static int acpi_memory_device_add(struct acpi_device *device,
+ const struct acpi_device_id *not_used)
+{
+ struct acpi_memory_device *mem_device;
+ int result;
+
+ if (!device)
+ return -EINVAL;
+
+ mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
+ if (!mem_device)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&mem_device->res_list);
+ mem_device->device = device;
+ sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
+ sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
+ device->driver_data = mem_device;
+
+ /* Get the range from the _CRS */
+ result = acpi_memory_get_device_resources(mem_device);
+ if (result) {
+ device->driver_data = NULL;
+ kfree(mem_device);
+ return result;
+ }
+
+ /* Set the device state */
+ mem_device->state = MEMORY_POWER_ON_STATE;
+
+ result = acpi_memory_check_device(mem_device);
+ if (result) {
+ acpi_memory_device_free(mem_device);
+ return 0;
+ }
+
+ result = acpi_memory_enable_device(mem_device);
+ if (result) {
+ dev_err(&device->dev, "acpi_memory_enable_device() error\n");
+ acpi_memory_device_free(mem_device);
+ return result;
+ }
+
+ dev_dbg(&device->dev, "Memory device configured by ACPI\n");
+ return 1;
+}
+
+static void acpi_memory_device_remove(struct acpi_device *device)
+{
+ struct acpi_memory_device *mem_device;
+
+ if (!device || !acpi_driver_data(device))
+ return;
+
+ mem_device = acpi_driver_data(device);
+ acpi_memory_remove_memory(mem_device);
+ acpi_memory_device_free(mem_device);
+}
+
+static bool __initdata acpi_no_memhotplug;
+
+void __init acpi_memory_hotplug_init(void)
+{
+ if (acpi_no_memhotplug) {
+ memory_device_handler.attach = NULL;
+ acpi_scan_add_handler(&memory_device_handler);
+ return;
+ }
+ acpi_scan_add_handler_with_hotplug(&memory_device_handler, "memory");
+}
+
+static int __init disable_acpi_memory_hotplug(char *str)
+{
+ acpi_no_memhotplug = true;
+ return 1;
+}
+__setup("acpi_no_memhotplug", disable_acpi_memory_hotplug);
+
+#else
+
+static struct acpi_scan_handler memory_device_handler = {
+ .ids = memory_device_ids,
+};
+
+void __init acpi_memory_hotplug_init(void)
+{
+ acpi_scan_add_handler(&memory_device_handler);
+}
+
+#endif /* CONFIG_ACPI_HOTPLUG_MEMORY */
Code Review / kvmfornfv.git / blobdiff