]> rtime.felk.cvut.cz Git - linux-imx.git/commitdiff
Merge branch 'acpi-hotplug'
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>
Fri, 28 Jun 2013 10:58:05 +0000 (12:58 +0200)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Fri, 28 Jun 2013 10:58:05 +0000 (12:58 +0200)
* acpi-hotplug:
  ACPI: Do not use CONFIG_ACPI_HOTPLUG_MEMORY_MODULE
  ACPI / cpufreq: Add ACPI processor device IDs to acpi-cpufreq
  Memory hotplug: Move alternative function definitions to header
  ACPI / processor: Fix potential NULL pointer dereference in acpi_processor_add()
  Memory hotplug / ACPI: Simplify memory removal
  ACPI / scan: Add second pass of companion offlining to hot-remove code
  Driver core / MM: Drop offline_memory_block()
  ACPI / processor: Pass processor object handle to acpi_bind_one()
  ACPI: Drop removal_type field from struct acpi_device
  Driver core / memory: Simplify __memory_block_change_state()
  ACPI / processor: Initialize per_cpu(processors, pr->id) properly
  CPU: Fix sysfs cpu/online of offlined CPUs
  Driver core: Introduce offline/online callbacks for memory blocks
  ACPI / memhotplug: Bind removable memory blocks to ACPI device nodes
  ACPI / processor: Use common hotplug infrastructure
  ACPI / hotplug: Use device offline/online for graceful hot-removal
  Driver core: Use generic offline/online for CPU offline/online
  Driver core: Add offline/online device operations

20 files changed:
Documentation/ABI/testing/sysfs-devices-online [new file with mode: 0644]
Documentation/ABI/testing/sysfs-firmware-acpi
drivers/acpi/Makefile
drivers/acpi/acpi_memhotplug.c
drivers/acpi/acpi_processor.c [new file with mode: 0644]
drivers/acpi/glue.c
drivers/acpi/internal.h
drivers/acpi/processor_driver.c
drivers/acpi/scan.c
drivers/acpi/sysfs.c
drivers/base/core.c
drivers/base/cpu.c
drivers/base/memory.c
drivers/cpufreq/acpi-cpufreq.c
include/acpi/acpi_bus.h
include/acpi/processor.h
include/linux/acpi.h
include/linux/device.h
include/linux/memory_hotplug.h
mm/memory_hotplug.c

diff --git a/Documentation/ABI/testing/sysfs-devices-online b/Documentation/ABI/testing/sysfs-devices-online
new file mode 100644 (file)
index 0000000..f990026
--- /dev/null
@@ -0,0 +1,20 @@
+What:          /sys/devices/.../online
+Date:          April 2013
+Contact:       Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+               The /sys/devices/.../online attribute is only present for
+               devices whose bus types provide .online() and .offline()
+               callbacks.  The number read from it (0 or 1) reflects the value
+               of the device's 'offline' field.  If that number is 1 and '0'
+               (or 'n', or 'N') is written to this file, the device bus type's
+               .offline() callback is executed for the device and (if
+               successful) its 'offline' field is updated accordingly.  In
+               turn, if that number is 0 and '1' (or 'y', or 'Y') is written to
+               this file, the device bus type's .online() callback is executed
+               for the device and (if successful) its 'offline' field is
+               updated as appropriate.
+
+               After a successful execution of the bus type's .offline()
+               callback the device cannot be used for any purpose until either
+               it is removed (i.e. device_del() is called for it), or its bus
+               type's .online() is exeucted successfully.
index ce9bee98b43be62f84937502ed6fdfae38d43b3d..b4436cca97a83612fd3305630f5e0807eb53caeb 100644 (file)
@@ -44,6 +44,16 @@ Description:
                or 0 (unset).  Attempts to write any other values to it will
                cause -EINVAL to be returned.
 
+What:          /sys/firmware/acpi/hotplug/force_remove
+Date:          May 2013
+Contact:       Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+               The number in this file (0 or 1) determines whether (1) or not
+               (0) the ACPI subsystem will allow devices to be hot-removed even
+               if they cannot be put offline gracefully (from the kernel's
+               viewpoint).  That number can be changed by writing a boolean
+               value to this file.
+
 What:          /sys/firmware/acpi/interrupts/
 Date:          February 2008
 Contact:       Len Brown <lenb@kernel.org>
index 536562c626a2fab4bb20c128abcf27f4404ca23f..d07771bc3d8c846ebd83bc8cded5aac7572d34c9 100644 (file)
@@ -34,6 +34,7 @@ acpi-$(CONFIG_ACPI_SLEEP)     += proc.o
 acpi-y                         += bus.o glue.o
 acpi-y                         += scan.o
 acpi-y                         += resource.o
+acpi-y                         += acpi_processor.o
 acpi-y                         += processor_core.o
 acpi-y                         += ec.o
 acpi-$(CONFIG_ACPI_DOCK)       += dock.o
index 5e6301e949206adb9f9b512a4b44b9d093e588df..c711d1144044ec18b47a8aad9f0c0f43e5f5f690 100644 (file)
@@ -28,6 +28,7 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/memory.h>
 #include <linux/memory_hotplug.h>
 
 #include "internal.h"
@@ -166,13 +167,50 @@ static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
        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, (acpi_handle)arg);
+}
+
+static int acpi_bind_memory_blocks(struct acpi_memory_info *info,
+                                  acpi_handle handle)
+{
+       return walk_memory_range(acpi_meminfo_start_pfn(info),
+                                acpi_meminfo_end_pfn(info), (void *)handle,
+                                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,
+                                     acpi_handle handle)
+{
+       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(mem_device->device->handle);
+       node = acpi_get_node(handle);
        /*
         * Tell the VM there is more memory here...
         * Note: Assume that this function returns zero on success
@@ -203,6 +241,12 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
                if (result && result != -EEXIST)
                        continue;
 
+               result = acpi_bind_memory_blocks(info, handle);
+               if (result) {
+                       acpi_unbind_memory_blocks(info, handle);
+                       return -ENODEV;
+               }
+
                info->enabled = 1;
 
                /*
@@ -227,12 +271,11 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
        return 0;
 }
 
-static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
+static void acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
 {
-       int result = 0, nid;
+       acpi_handle handle = mem_device->device->handle;
        struct acpi_memory_info *info, *n;
-
-       nid = acpi_get_node(mem_device->device->handle);
+       int nid = acpi_get_node(handle);
 
        list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
                if (!info->enabled)
@@ -240,15 +283,12 @@ static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device)
 
                if (nid < 0)
                        nid = memory_add_physaddr_to_nid(info->start_addr);
-               result = remove_memory(nid, info->start_addr, info->length);
-               if (result)
-                       return result;
 
+               acpi_unbind_memory_blocks(info, handle);
+               remove_memory(nid, info->start_addr, info->length);
                list_del(&info->list);
                kfree(info);
        }
-
-       return result;
 }
 
 static void acpi_memory_device_free(struct acpi_memory_device *mem_device)
@@ -300,7 +340,7 @@ static int acpi_memory_device_add(struct acpi_device *device,
        if (result) {
                dev_err(&device->dev, "acpi_memory_enable_device() error\n");
                acpi_memory_device_free(mem_device);
-               return -ENODEV;
+               return result;
        }
 
        dev_dbg(&device->dev, "Memory device configured by ACPI\n");
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
new file mode 100644 (file)
index 0000000..e9b01e3
--- /dev/null
@@ -0,0 +1,494 @@
+/*
+ * acpi_processor.c - ACPI processor enumeration support
+ *
+ * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Copyright (C) 2004       Dominik Brodowski <linux@brodo.de>
+ * Copyright (C) 2004  Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
+ * Copyright (C) 2013, Intel Corporation
+ *                     Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#include <acpi/processor.h>
+
+#include <asm/cpu.h>
+
+#include "internal.h"
+
+#define _COMPONENT     ACPI_PROCESSOR_COMPONENT
+
+ACPI_MODULE_NAME("processor");
+
+DEFINE_PER_CPU(struct acpi_processor *, processors);
+EXPORT_PER_CPU_SYMBOL(processors);
+
+/* --------------------------------------------------------------------------
+                                Errata Handling
+   -------------------------------------------------------------------------- */
+
+struct acpi_processor_errata errata __read_mostly;
+EXPORT_SYMBOL_GPL(errata);
+
+static int acpi_processor_errata_piix4(struct pci_dev *dev)
+{
+       u8 value1 = 0;
+       u8 value2 = 0;
+
+
+       if (!dev)
+               return -EINVAL;
+
+       /*
+        * Note that 'dev' references the PIIX4 ACPI Controller.
+        */
+
+       switch (dev->revision) {
+       case 0:
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
+               break;
+       case 1:
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
+               break;
+       case 2:
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
+               break;
+       case 3:
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
+               break;
+       default:
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
+               break;
+       }
+
+       switch (dev->revision) {
+
+       case 0:         /* PIIX4 A-step */
+       case 1:         /* PIIX4 B-step */
+               /*
+                * See specification changes #13 ("Manual Throttle Duty Cycle")
+                * and #14 ("Enabling and Disabling Manual Throttle"), plus
+                * erratum #5 ("STPCLK# Deassertion Time") from the January
+                * 2002 PIIX4 specification update.  Applies to only older
+                * PIIX4 models.
+                */
+               errata.piix4.throttle = 1;
+
+       case 2:         /* PIIX4E */
+       case 3:         /* PIIX4M */
+               /*
+                * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
+                * Livelock") from the January 2002 PIIX4 specification update.
+                * Applies to all PIIX4 models.
+                */
+
+               /*
+                * BM-IDE
+                * ------
+                * Find the PIIX4 IDE Controller and get the Bus Master IDE
+                * Status register address.  We'll use this later to read
+                * each IDE controller's DMA status to make sure we catch all
+                * DMA activity.
+                */
+               dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
+                                    PCI_DEVICE_ID_INTEL_82371AB,
+                                    PCI_ANY_ID, PCI_ANY_ID, NULL);
+               if (dev) {
+                       errata.piix4.bmisx = pci_resource_start(dev, 4);
+                       pci_dev_put(dev);
+               }
+
+               /*
+                * Type-F DMA
+                * ----------
+                * Find the PIIX4 ISA Controller and read the Motherboard
+                * DMA controller's status to see if Type-F (Fast) DMA mode
+                * is enabled (bit 7) on either channel.  Note that we'll
+                * disable C3 support if this is enabled, as some legacy
+                * devices won't operate well if fast DMA is disabled.
+                */
+               dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
+                                    PCI_DEVICE_ID_INTEL_82371AB_0,
+                                    PCI_ANY_ID, PCI_ANY_ID, NULL);
+               if (dev) {
+                       pci_read_config_byte(dev, 0x76, &value1);
+                       pci_read_config_byte(dev, 0x77, &value2);
+                       if ((value1 & 0x80) || (value2 & 0x80))
+                               errata.piix4.fdma = 1;
+                       pci_dev_put(dev);
+               }
+
+               break;
+       }
+
+       if (errata.piix4.bmisx)
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                 "Bus master activity detection (BM-IDE) erratum enabled\n"));
+       if (errata.piix4.fdma)
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                 "Type-F DMA livelock erratum (C3 disabled)\n"));
+
+       return 0;
+}
+
+static int acpi_processor_errata(struct acpi_processor *pr)
+{
+       int result = 0;
+       struct pci_dev *dev = NULL;
+
+
+       if (!pr)
+               return -EINVAL;
+
+       /*
+        * PIIX4
+        */
+       dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
+                            PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
+                            PCI_ANY_ID, NULL);
+       if (dev) {
+               result = acpi_processor_errata_piix4(dev);
+               pci_dev_put(dev);
+       }
+
+       return result;
+}
+
+/* --------------------------------------------------------------------------
+                                Initialization
+   -------------------------------------------------------------------------- */
+
+#ifdef CONFIG_ACPI_HOTPLUG_CPU
+static int acpi_processor_hotadd_init(struct acpi_processor *pr)
+{
+       unsigned long long sta;
+       acpi_status status;
+       int ret;
+
+       status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
+       if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
+               return -ENODEV;
+
+       ret = acpi_map_lsapic(pr->handle, &pr->id);
+       if (ret)
+               return ret;
+
+       ret = arch_register_cpu(pr->id);
+       if (ret) {
+               acpi_unmap_lsapic(pr->id);
+               return ret;
+       }
+
+       /*
+        * CPU got hot-added, but cpu_data is not initialized yet.  Set a flag
+        * to delay cpu_idle/throttling initialization and do it when the CPU
+        * gets online for the first time.
+        */
+       pr_info("CPU%d has been hot-added\n", pr->id);
+       pr->flags.need_hotplug_init = 1;
+       return 0;
+}
+#else
+static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
+{
+       return -ENODEV;
+}
+#endif /* CONFIG_ACPI_HOTPLUG_CPU */
+
+static int acpi_processor_get_info(struct acpi_device *device)
+{
+       union acpi_object object = { 0 };
+       struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
+       struct acpi_processor *pr = acpi_driver_data(device);
+       int cpu_index, device_declaration = 0;
+       acpi_status status = AE_OK;
+       static int cpu0_initialized;
+
+       if (num_online_cpus() > 1)
+               errata.smp = TRUE;
+
+       acpi_processor_errata(pr);
+
+       /*
+        * Check to see if we have bus mastering arbitration control.  This
+        * is required for proper C3 usage (to maintain cache coherency).
+        */
+       if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
+               pr->flags.bm_control = 1;
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                 "Bus mastering arbitration control present\n"));
+       } else
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                 "No bus mastering arbitration control\n"));
+
+       if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
+               /* Declared with "Processor" statement; match ProcessorID */
+               status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
+               if (ACPI_FAILURE(status)) {
+                       dev_err(&device->dev,
+                               "Failed to evaluate processor object (0x%x)\n",
+                               status);
+                       return -ENODEV;
+               }
+
+               /*
+                * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
+                *      >>> 'acpi_get_processor_id(acpi_id, &id)' in
+                *      arch/xxx/acpi.c
+                */
+               pr->acpi_id = object.processor.proc_id;
+       } else {
+               /*
+                * Declared with "Device" statement; match _UID.
+                * Note that we don't handle string _UIDs yet.
+                */
+               unsigned long long value;
+               status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
+                                               NULL, &value);
+               if (ACPI_FAILURE(status)) {
+                       dev_err(&device->dev,
+                               "Failed to evaluate processor _UID (0x%x)\n",
+                               status);
+                       return -ENODEV;
+               }
+               device_declaration = 1;
+               pr->acpi_id = value;
+       }
+       cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id);
+
+       /* Handle UP system running SMP kernel, with no LAPIC in MADT */
+       if (!cpu0_initialized && (cpu_index == -1) &&
+           (num_online_cpus() == 1)) {
+               cpu_index = 0;
+       }
+
+       cpu0_initialized = 1;
+
+       pr->id = cpu_index;
+
+       /*
+        *  Extra Processor objects may be enumerated on MP systems with
+        *  less than the max # of CPUs. They should be ignored _iff
+        *  they are physically not present.
+        */
+       if (pr->id == -1) {
+               int ret = acpi_processor_hotadd_init(pr);
+               if (ret)
+                       return ret;
+       }
+       /*
+        * On some boxes several processors use the same processor bus id.
+        * But they are located in different scope. For example:
+        * \_SB.SCK0.CPU0
+        * \_SB.SCK1.CPU0
+        * Rename the processor device bus id. And the new bus id will be
+        * generated as the following format:
+        * CPU+CPU ID.
+        */
+       sprintf(acpi_device_bid(device), "CPU%X", pr->id);
+       ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
+                         pr->acpi_id));
+
+       if (!object.processor.pblk_address)
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
+       else if (object.processor.pblk_length != 6)
+               dev_err(&device->dev, "Invalid PBLK length [%d]\n",
+                           object.processor.pblk_length);
+       else {
+               pr->throttling.address = object.processor.pblk_address;
+               pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
+               pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
+
+               pr->pblk = object.processor.pblk_address;
+
+               /*
+                * We don't care about error returns - we just try to mark
+                * these reserved so that nobody else is confused into thinking
+                * that this region might be unused..
+                *
+                * (In particular, allocating the IO range for Cardbus)
+                */
+               request_region(pr->throttling.address, 6, "ACPI CPU throttle");
+       }
+
+       /*
+        * If ACPI describes a slot number for this CPU, we can use it to
+        * ensure we get the right value in the "physical id" field
+        * of /proc/cpuinfo
+        */
+       status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer);
+       if (ACPI_SUCCESS(status))
+               arch_fix_phys_package_id(pr->id, object.integer.value);
+
+       return 0;
+}
+
+/*
+ * Do not put anything in here which needs the core to be online.
+ * For example MSR access or setting up things which check for cpuinfo_x86
+ * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
+ * Such things have to be put in and set up by the processor driver's .probe().
+ */
+static DEFINE_PER_CPU(void *, processor_device_array);
+
+static int __cpuinit acpi_processor_add(struct acpi_device *device,
+                                       const struct acpi_device_id *id)
+{
+       struct acpi_processor *pr;
+       struct device *dev;
+       int result = 0;
+
+       pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
+       if (!pr)
+               return -ENOMEM;
+
+       if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
+               result = -ENOMEM;
+               goto err_free_pr;
+       }
+
+       pr->handle = device->handle;
+       strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
+       strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
+       device->driver_data = pr;
+
+       result = acpi_processor_get_info(device);
+       if (result) /* Processor is not physically present or unavailable */
+               return 0;
+
+#ifdef CONFIG_SMP
+       if (pr->id >= setup_max_cpus && pr->id != 0)
+               return 0;
+#endif
+
+       BUG_ON(pr->id >= nr_cpu_ids);
+
+       /*
+        * Buggy BIOS check.
+        * ACPI id of processors can be reported wrongly by the BIOS.
+        * Don't trust it blindly
+        */
+       if (per_cpu(processor_device_array, pr->id) != NULL &&
+           per_cpu(processor_device_array, pr->id) != device) {
+               dev_warn(&device->dev,
+                       "BIOS reported wrong ACPI id %d for the processor\n",
+                       pr->id);
+               /* Give up, but do not abort the namespace scan. */
+               goto err;
+       }
+       /*
+        * processor_device_array is not cleared on errors to allow buggy BIOS
+        * checks.
+        */
+       per_cpu(processor_device_array, pr->id) = device;
+       per_cpu(processors, pr->id) = pr;
+
+       dev = get_cpu_device(pr->id);
+       if (!dev) {
+               result = -ENODEV;
+               goto err;
+       }
+
+       result = acpi_bind_one(dev, pr->handle);
+       if (result)
+               goto err;
+
+       pr->dev = dev;
+       dev->offline = pr->flags.need_hotplug_init;
+
+       /* Trigger the processor driver's .probe() if present. */
+       if (device_attach(dev) >= 0)
+               return 1;
+
+       dev_err(dev, "Processor driver could not be attached\n");
+       acpi_unbind_one(dev);
+
+ err:
+       free_cpumask_var(pr->throttling.shared_cpu_map);
+       device->driver_data = NULL;
+       per_cpu(processors, pr->id) = NULL;
+ err_free_pr:
+       kfree(pr);
+       return result;
+}
+
+#ifdef CONFIG_ACPI_HOTPLUG_CPU
+/* --------------------------------------------------------------------------
+                                    Removal
+   -------------------------------------------------------------------------- */
+
+static void acpi_processor_remove(struct acpi_device *device)
+{
+       struct acpi_processor *pr;
+
+       if (!device || !acpi_driver_data(device))
+               return;
+
+       pr = acpi_driver_data(device);
+       if (pr->id >= nr_cpu_ids)
+               goto out;
+
+       /*
+        * The only reason why we ever get here is CPU hot-removal.  The CPU is
+        * already offline and the ACPI device removal locking prevents it from
+        * being put back online at this point.
+        *
+        * Unbind the driver from the processor device and detach it from the
+        * ACPI companion object.
+        */
+       device_release_driver(pr->dev);
+       acpi_unbind_one(pr->dev);
+
+       /* Clean up. */
+       per_cpu(processor_device_array, pr->id) = NULL;
+       per_cpu(processors, pr->id) = NULL;
+       try_offline_node(cpu_to_node(pr->id));
+
+       /* Remove the CPU. */
+       get_online_cpus();
+       arch_unregister_cpu(pr->id);
+       acpi_unmap_lsapic(pr->id);
+       put_online_cpus();
+
+ out:
+       free_cpumask_var(pr->throttling.shared_cpu_map);
+       kfree(pr);
+}
+#endif /* CONFIG_ACPI_HOTPLUG_CPU */
+
+/*
+ * The following ACPI IDs are known to be suitable for representing as
+ * processor devices.
+ */
+static const struct acpi_device_id processor_device_ids[] = {
+
+       { ACPI_PROCESSOR_OBJECT_HID, },
+       { ACPI_PROCESSOR_DEVICE_HID, },
+
+       { }
+};
+
+static struct acpi_scan_handler __refdata processor_handler = {
+       .ids = processor_device_ids,
+       .attach = acpi_processor_add,
+#ifdef CONFIG_ACPI_HOTPLUG_CPU
+       .detach = acpi_processor_remove,
+#endif
+       .hotplug = {
+               .enabled = true,
+       },
+};
+
+void __init acpi_processor_init(void)
+{
+       acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
+}
index 40a84cc6740c6c6522afc6bac6d5d5d2178a86bd..9783f400d857da574b8c275e74db17e4d3d27161 100644 (file)
@@ -105,7 +105,7 @@ acpi_handle acpi_get_child(acpi_handle parent, u64 address)
 }
 EXPORT_SYMBOL(acpi_get_child);
 
-static int acpi_bind_one(struct device *dev, acpi_handle handle)
+int acpi_bind_one(struct device *dev, acpi_handle handle)
 {
        struct acpi_device *acpi_dev;
        acpi_status status;
@@ -188,8 +188,9 @@ static int acpi_bind_one(struct device *dev, acpi_handle handle)
        kfree(physical_node);
        goto err;
 }
+EXPORT_SYMBOL_GPL(acpi_bind_one);
 
-static int acpi_unbind_one(struct device *dev)
+int acpi_unbind_one(struct device *dev)
 {
        struct acpi_device_physical_node *entry;
        struct acpi_device *acpi_dev;
@@ -238,6 +239,7 @@ err:
        dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
        return -EINVAL;
 }
+EXPORT_SYMBOL_GPL(acpi_unbind_one);
 
 static int acpi_platform_notify(struct device *dev)
 {
index c610a76d92c4b4bdf5deafae76252110460d5ed2..520073ba36b497bf47cb6835aaa4f7a8b0897b4a 100644 (file)
@@ -33,6 +33,7 @@ static inline void acpi_pci_slot_init(void) { }
 void acpi_pci_root_init(void);
 void acpi_pci_link_init(void);
 void acpi_pci_root_hp_init(void);
+void acpi_processor_init(void);
 void acpi_platform_init(void);
 int acpi_sysfs_init(void);
 #ifdef CONFIG_ACPI_CONTAINER
@@ -51,6 +52,8 @@ void acpi_memory_hotplug_init(void);
 static inline void acpi_memory_hotplug_init(void) {}
 #endif
 
+extern bool acpi_force_hot_remove;
+
 void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug,
                                    const char *name);
 int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
@@ -81,6 +84,8 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
                             int type, unsigned long long sta);
 void acpi_device_add_finalize(struct acpi_device *device);
 void acpi_free_pnp_ids(struct acpi_device_pnp *pnp);
+int acpi_bind_one(struct device *dev, acpi_handle handle);
+int acpi_unbind_one(struct device *dev);
 
 /* --------------------------------------------------------------------------
                                   Power Resource
index c266cdc117840bcdfc7909c2605840501b2c87c2..d93963f1e8f435d735cf0bbdaded9e568f35a1d6 100644 (file)
@@ -1,11 +1,13 @@
 /*
- * acpi_processor.c - ACPI Processor Driver ($Revision: 71 $)
+ * processor_driver.c - ACPI Processor Driver
  *
  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
  *  Copyright (C) 2004       Dominik Brodowski <linux@brodo.de>
  *  Copyright (C) 2004  Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
  *                     - Added processor hotplug support
+ *  Copyright (C) 2013, Intel Corporation
+ *                      Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  *
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  *
  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  *
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- *  TBD:
- *     1. Make # power states dynamic.
- *     2. Support duty_cycle values that span bit 4.
- *     3. Optimize by having scheduler determine business instead of
- *        having us try to calculate it here.
- *     4. Need C1 timing -- must modify kernel (IRQ handler) to get this.
  */
 
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
-#include <linux/types.h>
-#include <linux/pci.h>
-#include <linux/pm.h>
 #include <linux/cpufreq.h>
 #include <linux/cpu.h>
-#include <linux/dmi.h>
-#include <linux/moduleparam.h>
 #include <linux/cpuidle.h>
 #include <linux/slab.h>
 #include <linux/acpi.h>
-#include <linux/memory_hotplug.h>
-
-#include <asm/io.h>
-#include <asm/cpu.h>
-#include <asm/delay.h>
-#include <asm/uaccess.h>
-#include <asm/processor.h>
-#include <asm/smp.h>
-#include <asm/acpi.h>
-
-#include <acpi/acpi_bus.h>
-#include <acpi/acpi_drivers.h>
+
 #include <acpi/processor.h>
 
+#include "internal.h"
+
 #define PREFIX "ACPI: "
 
-#define ACPI_PROCESSOR_CLASS           "processor"
-#define ACPI_PROCESSOR_DEVICE_NAME     "Processor"
 #define ACPI_PROCESSOR_FILE_INFO       "info"
 #define ACPI_PROCESSOR_FILE_THROTTLING "throttling"
 #define ACPI_PROCESSOR_FILE_LIMIT      "limit"
 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
 #define ACPI_PROCESSOR_NOTIFY_POWER    0x81
 #define ACPI_PROCESSOR_NOTIFY_THROTTLING       0x82
-#define ACPI_PROCESSOR_DEVICE_HID      "ACPI0007"
 
 #define ACPI_PROCESSOR_LIMIT_USER      0
 #define ACPI_PROCESSOR_LIMIT_THERMAL   1
@@ -81,12 +60,8 @@ MODULE_AUTHOR("Paul Diefenbaugh");
 MODULE_DESCRIPTION("ACPI Processor Driver");
 MODULE_LICENSE("GPL");
 
-static int acpi_processor_add(struct acpi_device *device);
-static int acpi_processor_remove(struct acpi_device *device);
-static void acpi_processor_notify(struct acpi_device *device, u32 event);
-static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr);
-static int acpi_processor_handle_eject(struct acpi_processor *pr);
-static int acpi_processor_start(struct acpi_processor *pr);
+static int acpi_processor_start(struct device *dev);
+static int acpi_processor_stop(struct device *dev);
 
 static const struct acpi_device_id processor_device_ids[] = {
        {ACPI_PROCESSOR_OBJECT_HID, 0},
@@ -95,295 +70,24 @@ static const struct acpi_device_id processor_device_ids[] = {
 };
 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
 
-static struct acpi_driver acpi_processor_driver = {
+static struct device_driver acpi_processor_driver = {
        .name = "processor",
-       .class = ACPI_PROCESSOR_CLASS,
-       .ids = processor_device_ids,
-       .ops = {
-               .add = acpi_processor_add,
-               .remove = acpi_processor_remove,
-               .notify = acpi_processor_notify,
-               },
+       .bus = &cpu_subsys,
+       .acpi_match_table = processor_device_ids,
+       .probe = acpi_processor_start,
+       .remove = acpi_processor_stop,
 };
 
-#define INSTALL_NOTIFY_HANDLER         1
-#define UNINSTALL_NOTIFY_HANDLER       2
-
-DEFINE_PER_CPU(struct acpi_processor *, processors);
-EXPORT_PER_CPU_SYMBOL(processors);
-
-struct acpi_processor_errata errata __read_mostly;
-
-/* --------------------------------------------------------------------------
-                                Errata Handling
-   -------------------------------------------------------------------------- */
-
-static int acpi_processor_errata_piix4(struct pci_dev *dev)
+static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
 {
-       u8 value1 = 0;
-       u8 value2 = 0;
-
-
-       if (!dev)
-               return -EINVAL;
-
-       /*
-        * Note that 'dev' references the PIIX4 ACPI Controller.
-        */
-
-       switch (dev->revision) {
-       case 0:
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
-               break;
-       case 1:
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
-               break;
-       case 2:
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
-               break;
-       case 3:
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
-               break;
-       default:
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
-               break;
-       }
-
-       switch (dev->revision) {
-
-       case 0:         /* PIIX4 A-step */
-       case 1:         /* PIIX4 B-step */
-               /*
-                * See specification changes #13 ("Manual Throttle Duty Cycle")
-                * and #14 ("Enabling and Disabling Manual Throttle"), plus
-                * erratum #5 ("STPCLK# Deassertion Time") from the January
-                * 2002 PIIX4 specification update.  Applies to only older
-                * PIIX4 models.
-                */
-               errata.piix4.throttle = 1;
-
-       case 2:         /* PIIX4E */
-       case 3:         /* PIIX4M */
-               /*
-                * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
-                * Livelock") from the January 2002 PIIX4 specification update.
-                * Applies to all PIIX4 models.
-                */
-
-               /*
-                * BM-IDE
-                * ------
-                * Find the PIIX4 IDE Controller and get the Bus Master IDE
-                * Status register address.  We'll use this later to read
-                * each IDE controller's DMA status to make sure we catch all
-                * DMA activity.
-                */
-               dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
-                                    PCI_DEVICE_ID_INTEL_82371AB,
-                                    PCI_ANY_ID, PCI_ANY_ID, NULL);
-               if (dev) {
-                       errata.piix4.bmisx = pci_resource_start(dev, 4);
-                       pci_dev_put(dev);
-               }
-
-               /*
-                * Type-F DMA
-                * ----------
-                * Find the PIIX4 ISA Controller and read the Motherboard
-                * DMA controller's status to see if Type-F (Fast) DMA mode
-                * is enabled (bit 7) on either channel.  Note that we'll
-                * disable C3 support if this is enabled, as some legacy
-                * devices won't operate well if fast DMA is disabled.
-                */
-               dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
-                                    PCI_DEVICE_ID_INTEL_82371AB_0,
-                                    PCI_ANY_ID, PCI_ANY_ID, NULL);
-               if (dev) {
-                       pci_read_config_byte(dev, 0x76, &value1);
-                       pci_read_config_byte(dev, 0x77, &value2);
-                       if ((value1 & 0x80) || (value2 & 0x80))
-                               errata.piix4.fdma = 1;
-                       pci_dev_put(dev);
-               }
-
-               break;
-       }
-
-       if (errata.piix4.bmisx)
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                 "Bus master activity detection (BM-IDE) erratum enabled\n"));
-       if (errata.piix4.fdma)
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                 "Type-F DMA livelock erratum (C3 disabled)\n"));
-
-       return 0;
-}
-
-static int acpi_processor_errata(struct acpi_processor *pr)
-{
-       int result = 0;
-       struct pci_dev *dev = NULL;
-
-
-       if (!pr)
-               return -EINVAL;
-
-       /*
-        * PIIX4
-        */
-       dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
-                            PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
-                            PCI_ANY_ID, NULL);
-       if (dev) {
-               result = acpi_processor_errata_piix4(dev);
-               pci_dev_put(dev);
-       }
-
-       return result;
-}
-
-/* --------------------------------------------------------------------------
-                                 Driver Interface
-   -------------------------------------------------------------------------- */
-
-static int acpi_processor_get_info(struct acpi_device *device)
-{
-       acpi_status status = 0;
-       union acpi_object object = { 0 };
-       struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
+       struct acpi_device *device = data;
        struct acpi_processor *pr;
-       int cpu_index, device_declaration = 0;
-       static int cpu0_initialized;
-
-       pr = acpi_driver_data(device);
-       if (!pr)
-               return -EINVAL;
-
-       if (num_online_cpus() > 1)
-               errata.smp = TRUE;
-
-       acpi_processor_errata(pr);
-
-       /*
-        * Check to see if we have bus mastering arbitration control.  This
-        * is required for proper C3 usage (to maintain cache coherency).
-        */
-       if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
-               pr->flags.bm_control = 1;
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                 "Bus mastering arbitration control present\n"));
-       } else
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                 "No bus mastering arbitration control\n"));
-
-       if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
-               /* Declared with "Processor" statement; match ProcessorID */
-               status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
-               if (ACPI_FAILURE(status)) {
-                       dev_err(&device->dev,
-                               "Failed to evaluate processor object (0x%x)\n",
-                               status);
-                       return -ENODEV;
-               }
-
-               /*
-                * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
-                *      >>> 'acpi_get_processor_id(acpi_id, &id)' in
-                *      arch/xxx/acpi.c
-                */
-               pr->acpi_id = object.processor.proc_id;
-       } else {
-               /*
-                * Declared with "Device" statement; match _UID.
-                * Note that we don't handle string _UIDs yet.
-                */
-               unsigned long long value;
-               status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
-                                               NULL, &value);
-               if (ACPI_FAILURE(status)) {
-                       dev_err(&device->dev,
-                               "Failed to evaluate processor _UID (0x%x)\n",
-                               status);
-                       return -ENODEV;
-               }
-               device_declaration = 1;
-               pr->acpi_id = value;
-       }
-       cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id);
-
-       /* Handle UP system running SMP kernel, with no LAPIC in MADT */
-       if (!cpu0_initialized && (cpu_index == -1) &&
-           (num_online_cpus() == 1)) {
-               cpu_index = 0;
-       }
-
-       cpu0_initialized = 1;
-
-       pr->id = cpu_index;
-
-       /*
-        *  Extra Processor objects may be enumerated on MP systems with
-        *  less than the max # of CPUs. They should be ignored _iff
-        *  they are physically not present.
-        */
-       if (pr->id == -1) {
-               if (ACPI_FAILURE(acpi_processor_hotadd_init(pr)))
-                       return -ENODEV;
-       }
-       /*
-        * On some boxes several processors use the same processor bus id.
-        * But they are located in different scope. For example:
-        * \_SB.SCK0.CPU0
-        * \_SB.SCK1.CPU0
-        * Rename the processor device bus id. And the new bus id will be
-        * generated as the following format:
-        * CPU+CPU ID.
-        */
-       sprintf(acpi_device_bid(device), "CPU%X", pr->id);
-       ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
-                         pr->acpi_id));
-
-       if (!object.processor.pblk_address)
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
-       else if (object.processor.pblk_length != 6)
-               dev_err(&device->dev, "Invalid PBLK length [%d]\n",
-                           object.processor.pblk_length);
-       else {
-               pr->throttling.address = object.processor.pblk_address;
-               pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
-               pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
-
-               pr->pblk = object.processor.pblk_address;
-
-               /*
-                * We don't care about error returns - we just try to mark
-                * these reserved so that nobody else is confused into thinking
-                * that this region might be unused..
-                *
-                * (In particular, allocating the IO range for Cardbus)
-                */
-               request_region(pr->throttling.address, 6, "ACPI CPU throttle");
-       }
-
-       /*
-        * If ACPI describes a slot number for this CPU, we can use it
-        * ensure we get the right value in the "physical id" field
-        * of /proc/cpuinfo
-        */
-       status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer);
-       if (ACPI_SUCCESS(status))
-               arch_fix_phys_package_id(pr->id, object.integer.value);
-
-       return 0;
-}
-
-static DEFINE_PER_CPU(void *, processor_device_array);
-
-static void acpi_processor_notify(struct acpi_device *device, u32 event)
-{
-       struct acpi_processor *pr = acpi_driver_data(device);
        int saved;
 
+       if (device->handle != handle)
+               return;
+
+       pr = acpi_driver_data(device);
        if (!pr)
                return;
 
@@ -420,55 +124,62 @@ static void acpi_processor_notify(struct acpi_device *device, u32 event)
        return;
 }
 
-static int acpi_cpu_soft_notify(struct notifier_block *nfb,
-               unsigned long action, void *hcpu)
+static __cpuinit int __acpi_processor_start(struct acpi_device *device);
+
+static int __cpuinit acpi_cpu_soft_notify(struct notifier_block *nfb,
+                                         unsigned long action, void *hcpu)
 {
        unsigned int cpu = (unsigned long)hcpu;
        struct acpi_processor *pr = per_cpu(processors, cpu);
+       struct acpi_device *device;
+
+       if (!pr || acpi_bus_get_device(pr->handle, &device))
+               return NOTIFY_DONE;
 
-       if (action == CPU_ONLINE && pr) {
-               /* CPU got physically hotplugged and onlined the first time:
-                * Initialize missing things
+       if (action == CPU_ONLINE) {
+               /*
+                * CPU got physically hotplugged and onlined for the first time:
+                * Initialize missing things.
                 */
                if (pr->flags.need_hotplug_init) {
+                       int ret;
+
                        pr_info("Will online and init hotplugged CPU: %d\n",
                                pr->id);
-                       WARN(acpi_processor_start(pr), "Failed to start CPU:"
-                               " %d\n", pr->id);
                        pr->flags.need_hotplug_init = 0;
-               /* Normal CPU soft online event */
+                       ret = __acpi_processor_start(device);
+                       WARN(ret, "Failed to start CPU: %d\n", pr->id);
                } else {
+                       /* Normal CPU soft online event. */
                        acpi_processor_ppc_has_changed(pr, 0);
                        acpi_processor_hotplug(pr);
                        acpi_processor_reevaluate_tstate(pr, action);
                        acpi_processor_tstate_has_changed(pr);
                }
-       }
-       if (action == CPU_DEAD && pr) {
-               /* invalidate the flag.throttling after one CPU is offline */
+       } else if (action == CPU_DEAD) {
+               /* Invalidate flag.throttling after the CPU is offline. */
                acpi_processor_reevaluate_tstate(pr, action);
        }
        return NOTIFY_OK;
 }
 
-static struct notifier_block acpi_cpu_notifier =
+static struct notifier_block __refdata acpi_cpu_notifier =
 {
            .notifier_call = acpi_cpu_soft_notify,
 };
 
-/*
- * acpi_processor_start() is called by the cpu_hotplug_notifier func:
- * acpi_cpu_soft_notify(). Getting it __cpuinit{data} is difficult, the
- * root cause seem to be that acpi_processor_uninstall_hotplug_notify()
- * is in the module_exit (__exit) func. Allowing acpi_processor_start()
- * to not be in __cpuinit section, but being called from __cpuinit funcs
- * via __ref looks like the right thing to do here.
- */
-static __ref int acpi_processor_start(struct acpi_processor *pr)
+static __cpuinit int __acpi_processor_start(struct acpi_device *device)
 {
-       struct acpi_device *device = per_cpu(processor_device_array, pr->id);
+       struct acpi_processor *pr = acpi_driver_data(device);
+       acpi_status status;
        int result = 0;
 
+       if (!pr)
+               return -ENODEV;
+
+       if (pr->flags.need_hotplug_init)
+               return 0;
+
 #ifdef CONFIG_CPU_FREQ
        acpi_processor_ppc_has_changed(pr, 0);
        acpi_processor_load_module(pr);
@@ -506,462 +217,95 @@ static __ref int acpi_processor_start(struct acpi_processor *pr)
                goto err_remove_sysfs_thermal;
        }
 
-       return 0;
+       status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+                                            acpi_processor_notify, device);
+       if (ACPI_SUCCESS(status))
+               return 0;
 
-err_remove_sysfs_thermal:
+       sysfs_remove_link(&pr->cdev->device.kobj, "device");
+ err_remove_sysfs_thermal:
        sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
-err_thermal_unregister:
+ err_thermal_unregister:
        thermal_cooling_device_unregister(pr->cdev);
-err_power_exit:
+ err_power_exit:
        acpi_processor_power_exit(pr);
-
        return result;
 }
 
-/*
- * Do not put anything in here which needs the core to be online.
- * For example MSR access or setting up things which check for cpuinfo_x86
- * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
- * Such things have to be put in and set up above in acpi_processor_start()
- */
-static int __cpuinit acpi_processor_add(struct acpi_device *device)
+static int __cpuinit acpi_processor_start(struct device *dev)
 {
-       struct acpi_processor *pr = NULL;
-       int result = 0;
-       struct device *dev;
-
-       pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
-       if (!pr)
-               return -ENOMEM;
-
-       if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
-               result = -ENOMEM;
-               goto err_free_pr;
-       }
-
-       pr->handle = device->handle;
-       strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
-       strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
-       device->driver_data = pr;
-
-       result = acpi_processor_get_info(device);
-       if (result) {
-               /* Processor is physically not present */
-               return 0;
-       }
-
-#ifdef CONFIG_SMP
-       if (pr->id >= setup_max_cpus && pr->id != 0)
-               return 0;
-#endif
-
-       BUG_ON(pr->id >= nr_cpu_ids);
-
-       /*
-        * Buggy BIOS check
-        * ACPI id of processors can be reported wrongly by the BIOS.
-        * Don't trust it blindly
-        */
-       if (per_cpu(processor_device_array, pr->id) != NULL &&
-           per_cpu(processor_device_array, pr->id) != device) {
-               dev_warn(&device->dev,
-                       "BIOS reported wrong ACPI id %d for the processor\n",
-                       pr->id);
-               result = -ENODEV;
-               goto err_free_cpumask;
-       }
-       per_cpu(processor_device_array, pr->id) = device;
-
-       per_cpu(processors, pr->id) = pr;
-
-       dev = get_cpu_device(pr->id);
-       if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
-               result = -EFAULT;
-               goto err_clear_processor;
-       }
+       struct acpi_device *device;
 
-       /*
-        * Do not start hotplugged CPUs now, but when they
-        * are onlined the first time
-        */
-       if (pr->flags.need_hotplug_init)
-               return 0;
-
-       result = acpi_processor_start(pr);
-       if (result)
-               goto err_remove_sysfs;
-
-       return 0;
+       if (acpi_bus_get_device(ACPI_HANDLE(dev), &device))
+               return -ENODEV;
 
-err_remove_sysfs:
-       sysfs_remove_link(&device->dev.kobj, "sysdev");
-err_clear_processor:
-       /*
-        * processor_device_array is not cleared to allow checks for buggy BIOS
-        */ 
-       per_cpu(processors, pr->id) = NULL;
-err_free_cpumask:
-       free_cpumask_var(pr->throttling.shared_cpu_map);
-err_free_pr:
-       kfree(pr);
-       return result;
+       return __acpi_processor_start(device);
 }
 
-static int acpi_processor_remove(struct acpi_device *device)
+static int acpi_processor_stop(struct device *dev)
 {
-       struct acpi_processor *pr = NULL;
+       struct acpi_device *device;
+       struct acpi_processor *pr;
 
+       if (acpi_bus_get_device(ACPI_HANDLE(dev), &device))
+               return 0;
 
-       if (!device || !acpi_driver_data(device))
-               return -EINVAL;
+       acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+                                  acpi_processor_notify);
 
        pr = acpi_driver_data(device);
-
-       if (pr->id >= nr_cpu_ids)
-               goto free;
-
-       if (device->removal_type == ACPI_BUS_REMOVAL_EJECT) {
-               if (acpi_processor_handle_eject(pr))
-                       return -EINVAL;
-       }
+       if (!pr)
+               return 0;
 
        acpi_processor_power_exit(pr);
 
-       sysfs_remove_link(&device->dev.kobj, "sysdev");
-
        if (pr->cdev) {
                sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
                sysfs_remove_link(&pr->cdev->device.kobj, "device");
                thermal_cooling_device_unregister(pr->cdev);
                pr->cdev = NULL;
        }
-
-       per_cpu(processors, pr->id) = NULL;
-       per_cpu(processor_device_array, pr->id) = NULL;
-       try_offline_node(cpu_to_node(pr->id));
-
-free:
-       free_cpumask_var(pr->throttling.shared_cpu_map);
-       kfree(pr);
-
        return 0;
 }
 
-#ifdef CONFIG_ACPI_HOTPLUG_CPU
-/****************************************************************************
- *     Acpi processor hotplug support                                      *
- ****************************************************************************/
-
-static int is_processor_present(acpi_handle handle)
-{
-       acpi_status status;
-       unsigned long long sta = 0;
-
-
-       status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
-
-       if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT))
-               return 1;
-
-       /*
-        * _STA is mandatory for a processor that supports hot plug
-        */
-       if (status == AE_NOT_FOUND)
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                               "Processor does not support hot plug\n"));
-       else
-               ACPI_EXCEPTION((AE_INFO, status,
-                               "Processor Device is not present"));
-       return 0;
-}
-
-static void acpi_processor_hotplug_notify(acpi_handle handle,
-                                         u32 event, void *data)
-{
-       struct acpi_device *device = NULL;
-       struct acpi_eject_event *ej_event = NULL;
-       u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
-       acpi_status status;
-       int result;
-
-       acpi_scan_lock_acquire();
-
-       switch (event) {
-       case ACPI_NOTIFY_BUS_CHECK:
-       case ACPI_NOTIFY_DEVICE_CHECK:
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-               "Processor driver received %s event\n",
-                      (event == ACPI_NOTIFY_BUS_CHECK) ?
-                      "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK"));
-
-               if (!is_processor_present(handle))
-                       break;
-
-               if (!acpi_bus_get_device(handle, &device))
-                       break;
-
-               result = acpi_bus_scan(handle);
-               if (result) {
-                       acpi_handle_err(handle, "Unable to add the device\n");
-                       break;
-               }
-               result = acpi_bus_get_device(handle, &device);
-               if (result) {
-                       acpi_handle_err(handle, "Missing device object\n");
-                       break;
-               }
-               ost_code = ACPI_OST_SC_SUCCESS;
-               break;
-
-       case ACPI_NOTIFY_EJECT_REQUEST:
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                 "received ACPI_NOTIFY_EJECT_REQUEST\n"));
-
-               if (acpi_bus_get_device(handle, &device)) {
-                       acpi_handle_err(handle,
-                               "Device don't exist, dropping EJECT\n");
-                       break;
-               }
-               if (!acpi_driver_data(device)) {
-                       acpi_handle_err(handle,
-                               "Driver data is NULL, dropping EJECT\n");
-                       break;
-               }
-
-               ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
-               if (!ej_event) {
-                       acpi_handle_err(handle, "No memory, dropping EJECT\n");
-                       break;
-               }
-
-               get_device(&device->dev);
-               ej_event->device = device;
-               ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
-               /* The eject is carried out asynchronously. */
-               status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device,
-                                                ej_event);
-               if (ACPI_FAILURE(status)) {
-                       put_device(&device->dev);
-                       kfree(ej_event);
-                       break;
-               }
-               goto out;
-
-       default:
-               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                 "Unsupported event [0x%x]\n", event));
-
-               /* non-hotplug event; possibly handled by other handler */
-               goto out;
-       }
-
-       /* Inform firmware that the hotplug operation has completed */
-       (void) acpi_evaluate_hotplug_ost(handle, event, ost_code, NULL);
-
- out:
-       acpi_scan_lock_release();
-}
-
-static acpi_status is_processor_device(acpi_handle handle)
-{
-       struct acpi_device_info *info;
-       char *hid;
-       acpi_status status;
-
-       status = acpi_get_object_info(handle, &info);
-       if (ACPI_FAILURE(status))
-               return status;
-
-       if (info->type == ACPI_TYPE_PROCESSOR) {
-               kfree(info);
-               return AE_OK;   /* found a processor object */
-       }
-
-       if (!(info->valid & ACPI_VALID_HID)) {
-               kfree(info);
-               return AE_ERROR;
-       }
-
-       hid = info->hardware_id.string;
-       if ((hid == NULL) || strcmp(hid, ACPI_PROCESSOR_DEVICE_HID)) {
-               kfree(info);
-               return AE_ERROR;
-       }
-
-       kfree(info);
-       return AE_OK;   /* found a processor device object */
-}
-
-static acpi_status
-processor_walk_namespace_cb(acpi_handle handle,
-                           u32 lvl, void *context, void **rv)
-{
-       acpi_status status;
-       int *action = context;
-
-       status = is_processor_device(handle);
-       if (ACPI_FAILURE(status))
-               return AE_OK;   /* not a processor; continue to walk */
-
-       switch (*action) {
-       case INSTALL_NOTIFY_HANDLER:
-               acpi_install_notify_handler(handle,
-                                           ACPI_SYSTEM_NOTIFY,
-                                           acpi_processor_hotplug_notify,
-                                           NULL);
-               break;
-       case UNINSTALL_NOTIFY_HANDLER:
-               acpi_remove_notify_handler(handle,
-                                          ACPI_SYSTEM_NOTIFY,
-                                          acpi_processor_hotplug_notify);
-               break;
-       default:
-               break;
-       }
-
-       /* found a processor; skip walking underneath */
-       return AE_CTRL_DEPTH;
-}
-
-static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
-{
-       acpi_handle handle = pr->handle;
-
-       if (!is_processor_present(handle)) {
-               return AE_ERROR;
-       }
-
-       if (acpi_map_lsapic(handle, &pr->id))
-               return AE_ERROR;
-
-       if (arch_register_cpu(pr->id)) {
-               acpi_unmap_lsapic(pr->id);
-               return AE_ERROR;
-       }
-
-       /* CPU got hot-plugged, but cpu_data is not initialized yet
-        * Set flag to delay cpu_idle/throttling initialization
-        * in:
-        * acpi_processor_add()
-        *   acpi_processor_get_info()
-        * and do it when the CPU gets online the first time
-        * TBD: Cleanup above functions and try to do this more elegant.
-        */
-       pr_info("CPU %d got hotplugged\n", pr->id);
-       pr->flags.need_hotplug_init = 1;
-
-       return AE_OK;
-}
-
-static int acpi_processor_handle_eject(struct acpi_processor *pr)
-{
-       if (cpu_online(pr->id))
-               cpu_down(pr->id);
-
-       get_online_cpus();
-       /*
-        * The cpu might become online again at this point. So we check whether
-        * the cpu has been onlined or not. If the cpu became online, it means
-        * that someone wants to use the cpu. So acpi_processor_handle_eject()
-        * returns -EAGAIN.
-        */
-       if (unlikely(cpu_online(pr->id))) {
-               put_online_cpus();
-               pr_warn("Failed to remove CPU %d, because other task "
-                       "brought the CPU back online\n", pr->id);
-               return -EAGAIN;
-       }
-       arch_unregister_cpu(pr->id);
-       acpi_unmap_lsapic(pr->id);
-       put_online_cpus();
-       return (0);
-}
-#else
-static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
-{
-       return AE_ERROR;
-}
-static int acpi_processor_handle_eject(struct acpi_processor *pr)
-{
-       return (-EINVAL);
-}
-#endif
-
-static
-void acpi_processor_install_hotplug_notify(void)
-{
-#ifdef CONFIG_ACPI_HOTPLUG_CPU
-       int action = INSTALL_NOTIFY_HANDLER;
-       acpi_walk_namespace(ACPI_TYPE_ANY,
-                           ACPI_ROOT_OBJECT,
-                           ACPI_UINT32_MAX,
-                           processor_walk_namespace_cb, NULL, &action, NULL);
-#endif
-       register_hotcpu_notifier(&acpi_cpu_notifier);
-}
-
-static
-void acpi_processor_uninstall_hotplug_notify(void)
-{
-#ifdef CONFIG_ACPI_HOTPLUG_CPU
-       int action = UNINSTALL_NOTIFY_HANDLER;
-       acpi_walk_namespace(ACPI_TYPE_ANY,
-                           ACPI_ROOT_OBJECT,
-                           ACPI_UINT32_MAX,
-                           processor_walk_namespace_cb, NULL, &action, NULL);
-#endif
-       unregister_hotcpu_notifier(&acpi_cpu_notifier);
-}
-
 /*
  * We keep the driver loaded even when ACPI is not running.
  * This is needed for the powernow-k8 driver, that works even without
  * ACPI, but needs symbols from this driver
  */
 
-static int __init acpi_processor_init(void)
+static int __init acpi_processor_driver_init(void)
 {
        int result = 0;
 
        if (acpi_disabled)
                return 0;
 
-       result = acpi_bus_register_driver(&acpi_processor_driver);
+       result = driver_register(&acpi_processor_driver);
        if (result < 0)
                return result;
 
        acpi_processor_syscore_init();
-
-       acpi_processor_install_hotplug_notify();
-
+       register_hotcpu_notifier(&acpi_cpu_notifier);
        acpi_thermal_cpufreq_init();
-
        acpi_processor_ppc_init();
-
        acpi_processor_throttling_init();
-
        return 0;
 }
 
-static void __exit acpi_processor_exit(void)
+static void __exit acpi_processor_driver_exit(void)
 {
        if (acpi_disabled)
                return;
 
        acpi_processor_ppc_exit();
-
        acpi_thermal_cpufreq_exit();
-
-       acpi_processor_uninstall_hotplug_notify();
-
+       unregister_hotcpu_notifier(&acpi_cpu_notifier);
        acpi_processor_syscore_exit();
-
-       acpi_bus_unregister_driver(&acpi_processor_driver);
-
-       return;
+       driver_unregister(&acpi_processor_driver);
 }
 
-module_init(acpi_processor_init);
-module_exit(acpi_processor_exit);
+module_init(acpi_processor_driver_init);
+module_exit(acpi_processor_driver_exit);
 
 MODULE_ALIAS("processor");
index 27da63061e11ae88c628242e0eed71fc0e1d7588..db118b1ad3e8cf30791feec2ca568bab20a5795f 100644 (file)
@@ -27,6 +27,12 @@ extern struct acpi_device *acpi_root;
 
 #define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
 
+/*
+ * If set, devices will be hot-removed even if they cannot be put offline
+ * gracefully (from the kernel's standpoint).
+ */
+bool acpi_force_hot_remove;
+
 static const char *dummy_hid = "device";
 
 static LIST_HEAD(acpi_device_list);
@@ -120,12 +126,78 @@ acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, cha
 }
 static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
 
+static acpi_status acpi_bus_offline_companions(acpi_handle handle, u32 lvl,
+                                              void *data, void **ret_p)
+{
+       struct acpi_device *device = NULL;
+       struct acpi_device_physical_node *pn;
+       bool second_pass = (bool)data;
+       acpi_status status = AE_OK;
+
+       if (acpi_bus_get_device(handle, &device))
+               return AE_OK;
+
+       mutex_lock(&device->physical_node_lock);
+
+       list_for_each_entry(pn, &device->physical_node_list, node) {
+               int ret;
+
+               if (second_pass) {
+                       /* Skip devices offlined by the first pass. */
+                       if (pn->put_online)
+                               continue;
+               } else {
+                       pn->put_online = false;
+               }
+               ret = device_offline(pn->dev);
+               if (acpi_force_hot_remove)
+                       continue;
+
+               if (ret >= 0) {
+                       pn->put_online = !ret;
+               } else {
+                       *ret_p = pn->dev;
+                       if (second_pass) {
+                               status = AE_ERROR;
+                               break;
+                       }
+               }
+       }
+
+       mutex_unlock(&device->physical_node_lock);
+
+       return status;
+}
+
+static acpi_status acpi_bus_online_companions(acpi_handle handle, u32 lvl,
+                                             void *data, void **ret_p)
+{
+       struct acpi_device *device = NULL;
+       struct acpi_device_physical_node *pn;
+
+       if (acpi_bus_get_device(handle, &device))
+               return AE_OK;
+
+       mutex_lock(&device->physical_node_lock);
+
+       list_for_each_entry(pn, &device->physical_node_list, node)
+               if (pn->put_online) {
+                       device_online(pn->dev);
+                       pn->put_online = false;
+               }
+
+       mutex_unlock(&device->physical_node_lock);
+
+       return AE_OK;
+}
+
 static int acpi_scan_hot_remove(struct acpi_device *device)
 {
        acpi_handle handle = device->handle;
        acpi_handle not_used;
        struct acpi_object_list arg_list;
        union acpi_object arg;
+       struct device *errdev;
        acpi_status status;
        unsigned long long sta;
 
@@ -136,10 +208,53 @@ static int acpi_scan_hot_remove(struct acpi_device *device)
                return -EINVAL;
        }
 
+       lock_device_hotplug();
+
+       /*
+        * Carry out two passes here and ignore errors in the first pass,
+        * because if the devices in question are memory blocks and
+        * CONFIG_MEMCG is set, one of the blocks may hold data structures
+        * that the other blocks depend on, but it is not known in advance which
+        * block holds them.
+        *
+        * If the first pass is successful, the second one isn't needed, though.
+        */
+       errdev = NULL;
+       acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
+                           NULL, acpi_bus_offline_companions,
+                           (void *)false, (void **)&errdev);
+       acpi_bus_offline_companions(handle, 0, (void *)false, (void **)&errdev);
+       if (errdev) {
+               errdev = NULL;
+               acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
+                                   NULL, acpi_bus_offline_companions,
+                                   (void *)true , (void **)&errdev);
+               if (!errdev || acpi_force_hot_remove)
+                       acpi_bus_offline_companions(handle, 0, (void *)true,
+                                                   (void **)&errdev);
+
+               if (errdev && !acpi_force_hot_remove) {
+                       dev_warn(errdev, "Offline failed.\n");
+                       acpi_bus_online_companions(handle, 0, NULL, NULL);
+                       acpi_walk_namespace(ACPI_TYPE_ANY, handle,
+                                           ACPI_UINT32_MAX,
+                                           acpi_bus_online_companions, NULL,
+                                           NULL, NULL);
+
+                       unlock_device_hotplug();
+
+                       put_device(&device->dev);
+                       return -EBUSY;
+               }
+       }
+
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                "Hot-removing device %s...\n", dev_name(&device->dev)));
 
        acpi_bus_trim(device);
+
+       unlock_device_hotplug();
+
        /* Device node has been unregistered. */
        put_device(&device->dev);
        device = NULL;
@@ -236,6 +351,7 @@ static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
        int error;
 
        mutex_lock(&acpi_scan_lock);
+       lock_device_hotplug();
 
        acpi_bus_get_device(handle, &device);
        if (device) {
@@ -259,6 +375,7 @@ static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source)
                kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
 
  out:
+       unlock_device_hotplug();
        acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL);
        mutex_unlock(&acpi_scan_lock);
 }
@@ -952,7 +1069,6 @@ int acpi_device_add(struct acpi_device *device,
                printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
                       dev_name(&device->dev));
 
-       device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
        return 0;
 
  err:
@@ -1939,7 +2055,6 @@ static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used,
        if (!acpi_bus_get_device(handle, &device)) {
                struct acpi_scan_handler *dev_handler = device->handler;
 
-               device->removal_type = ACPI_BUS_REMOVAL_EJECT;
                if (dev_handler) {
                        if (dev_handler->detach)
                                dev_handler->detach(device);
@@ -2038,6 +2153,7 @@ int __init acpi_scan_init(void)
 
        acpi_pci_root_init();
        acpi_pci_link_init();
+       acpi_processor_init();
        acpi_platform_init();
        acpi_lpss_init();
        acpi_container_init();
index fcae5fa2e1b322481ec2b331c4df0430bff66d53..5c5d1624fa2c261c8b6dca89a34156268a91d799 100644 (file)
@@ -780,6 +780,33 @@ void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug,
        pr_err(PREFIX "Unable to add hotplug profile '%s'\n", name);
 }
 
+static ssize_t force_remove_show(struct kobject *kobj,
+                                struct kobj_attribute *attr, char *buf)
+{
+       return sprintf(buf, "%d\n", !!acpi_force_hot_remove);
+}
+
+static ssize_t force_remove_store(struct kobject *kobj,
+                                 struct kobj_attribute *attr,
+                                 const char *buf, size_t size)
+{
+       bool val;
+       int ret;
+
+       ret = strtobool(buf, &val);
+       if (ret < 0)
+               return ret;
+
+       lock_device_hotplug();
+       acpi_force_hot_remove = val;
+       unlock_device_hotplug();
+       return size;
+}
+
+static const struct kobj_attribute force_remove_attr =
+       __ATTR(force_remove, S_IRUGO | S_IWUSR, force_remove_show,
+              force_remove_store);
+
 int __init acpi_sysfs_init(void)
 {
        int result;
@@ -789,6 +816,10 @@ int __init acpi_sysfs_init(void)
                return result;
 
        hotplug_kobj = kobject_create_and_add("hotplug", acpi_kobj);
+       result = sysfs_create_file(hotplug_kobj, &force_remove_attr.attr);
+       if (result)
+               return result;
+
        result = sysfs_create_file(acpi_kobj, &pm_profile_attr.attr);
        return result;
 }
index 2499cefdcdf2429d9503506d5514a4943f9ec4e1..2166f34b7d842ac7fa8d129858dac244e9e5394a 100644 (file)
@@ -403,6 +403,36 @@ static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
 static struct device_attribute uevent_attr =
        __ATTR(uevent, S_IRUGO | S_IWUSR, show_uevent, store_uevent);
 
+static ssize_t show_online(struct device *dev, struct device_attribute *attr,
+                          char *buf)
+{
+       bool val;
+
+       lock_device_hotplug();
+       val = !dev->offline;
+       unlock_device_hotplug();
+       return sprintf(buf, "%u\n", val);
+}
+
+static ssize_t store_online(struct device *dev, struct device_attribute *attr,
+                           const char *buf, size_t count)
+{
+       bool val;
+       int ret;
+
+       ret = strtobool(buf, &val);
+       if (ret < 0)
+               return ret;
+
+       lock_device_hotplug();
+       ret = val ? device_online(dev) : device_offline(dev);
+       unlock_device_hotplug();
+       return ret < 0 ? ret : count;
+}
+
+static struct device_attribute online_attr =
+       __ATTR(online, S_IRUGO | S_IWUSR, show_online, store_online);
+
 static int device_add_attributes(struct device *dev,
                                 struct device_attribute *attrs)
 {
@@ -516,6 +546,12 @@ static int device_add_attrs(struct device *dev)
        if (error)
                goto err_remove_type_groups;
 
+       if (device_supports_offline(dev) && !dev->offline_disabled) {
+               error = device_create_file(dev, &online_attr);
+               if (error)
+                       goto err_remove_type_groups;
+       }
+
        return 0;
 
  err_remove_type_groups:
@@ -536,6 +572,7 @@ static void device_remove_attrs(struct device *dev)
        struct class *class = dev->class;
        const struct device_type *type = dev->type;
 
+       device_remove_file(dev, &online_attr);
        device_remove_groups(dev, dev->groups);
 
        if (type)
@@ -1433,6 +1470,99 @@ EXPORT_SYMBOL_GPL(put_device);
 EXPORT_SYMBOL_GPL(device_create_file);
 EXPORT_SYMBOL_GPL(device_remove_file);
 
+static DEFINE_MUTEX(device_hotplug_lock);
+
+void lock_device_hotplug(void)
+{
+       mutex_lock(&device_hotplug_lock);
+}
+
+void unlock_device_hotplug(void)
+{
+       mutex_unlock(&device_hotplug_lock);
+}
+
+static int device_check_offline(struct device *dev, void *not_used)
+{
+       int ret;
+
+       ret = device_for_each_child(dev, NULL, device_check_offline);
+       if (ret)
+               return ret;
+
+       return device_supports_offline(dev) && !dev->offline ? -EBUSY : 0;
+}
+
+/**
+ * device_offline - Prepare the device for hot-removal.
+ * @dev: Device to be put offline.
+ *
+ * Execute the device bus type's .offline() callback, if present, to prepare
+ * the device for a subsequent hot-removal.  If that succeeds, the device must
+ * not be used until either it is removed or its bus type's .online() callback
+ * is executed.
+ *
+ * Call under device_hotplug_lock.
+ */
+int device_offline(struct device *dev)
+{
+       int ret;
+
+       if (dev->offline_disabled)
+               return -EPERM;
+
+       ret = device_for_each_child(dev, NULL, device_check_offline);
+       if (ret)
+               return ret;
+
+       device_lock(dev);
+       if (device_supports_offline(dev)) {
+               if (dev->offline) {
+                       ret = 1;
+               } else {
+                       ret = dev->bus->offline(dev);
+                       if (!ret) {
+                               kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
+                               dev->offline = true;
+                       }
+               }
+       }
+       device_unlock(dev);
+
+       return ret;
+}
+
+/**
+ * device_online - Put the device back online after successful device_offline().
+ * @dev: Device to be put back online.
+ *
+ * If device_offline() has been successfully executed for @dev, but the device
+ * has not been removed subsequently, execute its bus type's .online() callback
+ * to indicate that the device can be used again.
+ *
+ * Call under device_hotplug_lock.
+ */
+int device_online(struct device *dev)
+{
+       int ret = 0;
+
+       device_lock(dev);
+       if (device_supports_offline(dev)) {
+               if (dev->offline) {
+                       ret = dev->bus->online(dev);
+                       if (!ret) {
+                               kobject_uevent(&dev->kobj, KOBJ_ONLINE);
+                               dev->offline = false;
+                       }
+               } else {
+                       ret = 1;
+               }
+       }
+       device_unlock(dev);
+
+       return ret;
+}
+
 struct root_device {
        struct device dev;
        struct module *owner;
index 3d48fc887ef4b3a3da1aadefaf9129578e3d1ef2..1d110dc6f0c1f371ac262a9f6e352b5d626bf2fa 100644 (file)
 #include <linux/gfp.h>
 #include <linux/slab.h>
 #include <linux/percpu.h>
+#include <linux/acpi.h>
 
 #include "base.h"
 
-struct bus_type cpu_subsys = {
-       .name = "cpu",
-       .dev_name = "cpu",
-};
-EXPORT_SYMBOL_GPL(cpu_subsys);
-
 static DEFINE_PER_CPU(struct device *, cpu_sys_devices);
 
+static int cpu_subsys_match(struct device *dev, struct device_driver *drv)
+{
+       /* ACPI style match is the only one that may succeed. */
+       if (acpi_driver_match_device(dev, drv))
+               return 1;
+
+       return 0;
+}
+
 #ifdef CONFIG_HOTPLUG_CPU
 static void change_cpu_under_node(struct cpu *cpu,
                        unsigned int from_nid, unsigned int to_nid)
@@ -34,69 +38,45 @@ static void change_cpu_under_node(struct cpu *cpu,
        cpu->node_id = to_nid;
 }
 
-static ssize_t show_online(struct device *dev,
-                          struct device_attribute *attr,
-                          char *buf)
+static int __ref cpu_subsys_online(struct device *dev)
 {
        struct cpu *cpu = container_of(dev, struct cpu, dev);
+       int cpuid = dev->id;
+       int from_nid, to_nid;
+       int ret;
 
-       return sprintf(buf, "%u\n", !!cpu_online(cpu->dev.id));
+       cpu_hotplug_driver_lock();
+
+       from_nid = cpu_to_node(cpuid);
+       ret = cpu_up(cpuid);
+       /*
+        * When hot adding memory to memoryless node and enabling a cpu
+        * on the node, node number of the cpu may internally change.
+        */
+       to_nid = cpu_to_node(cpuid);
+       if (from_nid != to_nid)
+               change_cpu_under_node(cpu, from_nid, to_nid);
+
+       cpu_hotplug_driver_unlock();
+       return ret;
 }
 
-static ssize_t __ref store_online(struct device *dev,
-                                 struct device_attribute *attr,
-                                 const char *buf, size_t count)
+static int cpu_subsys_offline(struct device *dev)
 {
-       struct cpu *cpu = container_of(dev, struct cpu, dev);
-       int cpuid = cpu->dev.id;
-       int from_nid, to_nid;
-       ssize_t ret;
+       int ret;
 
        cpu_hotplug_driver_lock();
-       switch (buf[0]) {
-       case '0':
-               ret = cpu_down(cpuid);
-               if (!ret)
-                       kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
-               break;
-       case '1':
-               from_nid = cpu_to_node(cpuid);
-               ret = cpu_up(cpuid);
-
-               /*
-                * When hot adding memory to memoryless node and enabling a cpu
-                * on the node, node number of the cpu may internally change.
-                */
-               to_nid = cpu_to_node(cpuid);
-               if (from_nid != to_nid)
-                       change_cpu_under_node(cpu, from_nid, to_nid);
-
-               if (!ret)
-                       kobject_uevent(&dev->kobj, KOBJ_ONLINE);
-               break;
-       default:
-               ret = -EINVAL;
-       }
+       ret = cpu_down(dev->id);
        cpu_hotplug_driver_unlock();
-
-       if (ret >= 0)
-               ret = count;
        return ret;
 }
-static DEVICE_ATTR(online, 0644, show_online, store_online);
 
-static void __cpuinit register_cpu_control(struct cpu *cpu)
-{
-       device_create_file(&cpu->dev, &dev_attr_online);
-}
 void unregister_cpu(struct cpu *cpu)
 {
        int logical_cpu = cpu->dev.id;
 
        unregister_cpu_under_node(logical_cpu, cpu_to_node(logical_cpu));
 
-       device_remove_file(&cpu->dev, &dev_attr_online);
-
        device_unregister(&cpu->dev);
        per_cpu(cpu_sys_devices, logical_cpu) = NULL;
        return;
@@ -123,12 +103,19 @@ static DEVICE_ATTR(probe, S_IWUSR, NULL, cpu_probe_store);
 static DEVICE_ATTR(release, S_IWUSR, NULL, cpu_release_store);
 #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
 
-#else /* ... !CONFIG_HOTPLUG_CPU */
-static inline void register_cpu_control(struct cpu *cpu)
-{
-}
 #endif /* CONFIG_HOTPLUG_CPU */
 
+struct bus_type cpu_subsys = {
+       .name = "cpu",
+       .dev_name = "cpu",
+       .match = cpu_subsys_match,
+#ifdef CONFIG_HOTPLUG_CPU
+       .online = cpu_subsys_online,
+       .offline = cpu_subsys_offline,
+#endif
+};
+EXPORT_SYMBOL_GPL(cpu_subsys);
+
 #ifdef CONFIG_KEXEC
 #include <linux/kexec.h>
 
@@ -277,12 +264,12 @@ int __cpuinit register_cpu(struct cpu *cpu, int num)
        cpu->dev.id = num;
        cpu->dev.bus = &cpu_subsys;
        cpu->dev.release = cpu_device_release;
+       cpu->dev.offline_disabled = !cpu->hotpluggable;
+       cpu->dev.offline = !cpu_online(num);
 #ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE
        cpu->dev.bus->uevent = arch_cpu_uevent;
 #endif
        error = device_register(&cpu->dev);
-       if (!error && cpu->hotpluggable)
-               register_cpu_control(cpu);
        if (!error)
                per_cpu(cpu_sys_devices, num) = &cpu->dev;
        if (!error)
index 14f8a6954da0a11f1250b75b050318a9c63a4cb2..4ebf97f99fae0f84fb7d8f28bc9a9bd513f7b5aa 100644 (file)
@@ -37,9 +37,14 @@ static inline int base_memory_block_id(int section_nr)
        return section_nr / sections_per_block;
 }
 
+static int memory_subsys_online(struct device *dev);
+static int memory_subsys_offline(struct device *dev);
+
 static struct bus_type memory_subsys = {
        .name = MEMORY_CLASS_NAME,
        .dev_name = MEMORY_CLASS_NAME,
+       .online = memory_subsys_online,
+       .offline = memory_subsys_offline,
 };
 
 static BLOCKING_NOTIFIER_HEAD(memory_chain);
@@ -88,6 +93,7 @@ int register_memory(struct memory_block *memory)
        memory->dev.bus = &memory_subsys;
        memory->dev.id = memory->start_section_nr / sections_per_block;
        memory->dev.release = memory_block_release;
+       memory->dev.offline = memory->state == MEM_OFFLINE;
 
        error = device_register(&memory->dev);
        return error;
@@ -278,33 +284,64 @@ static int __memory_block_change_state(struct memory_block *mem,
 {
        int ret = 0;
 
-       if (mem->state != from_state_req) {
-               ret = -EINVAL;
-               goto out;
-       }
+       if (mem->state != from_state_req)
+               return -EINVAL;
 
        if (to_state == MEM_OFFLINE)
                mem->state = MEM_GOING_OFFLINE;
 
        ret = memory_block_action(mem->start_section_nr, to_state, online_type);
+       mem->state = ret ? from_state_req : to_state;
+       return ret;
+}
 
-       if (ret) {
-               mem->state = from_state_req;
-               goto out;
-       }
+static int memory_subsys_online(struct device *dev)
+{
+       struct memory_block *mem = container_of(dev, struct memory_block, dev);
+       int ret;
 
-       mem->state = to_state;
-       switch (mem->state) {
-       case MEM_OFFLINE:
-               kobject_uevent(&mem->dev.kobj, KOBJ_OFFLINE);
-               break;
-       case MEM_ONLINE:
-               kobject_uevent(&mem->dev.kobj, KOBJ_ONLINE);
-               break;
-       default:
-               break;
+       mutex_lock(&mem->state_mutex);
+
+       ret = mem->state == MEM_ONLINE ? 0 :
+               __memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE,
+                                           ONLINE_KEEP);
+
+       mutex_unlock(&mem->state_mutex);
+       return ret;
+}
+
+static int memory_subsys_offline(struct device *dev)
+{
+       struct memory_block *mem = container_of(dev, struct memory_block, dev);
+       int ret;
+
+       mutex_lock(&mem->state_mutex);
+
+       ret = mem->state == MEM_OFFLINE ? 0 :
+               __memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE, -1);
+
+       mutex_unlock(&mem->state_mutex);
+       return ret;
+}
+
+static int __memory_block_change_state_uevent(struct memory_block *mem,
+               unsigned long to_state, unsigned long from_state_req,
+               int online_type)
+{
+       int ret = __memory_block_change_state(mem, to_state, from_state_req,
+                                             online_type);
+       if (!ret) {
+               switch (mem->state) {
+               case MEM_OFFLINE:
+                       kobject_uevent(&mem->dev.kobj, KOBJ_OFFLINE);
+                       break;
+               case MEM_ONLINE:
+                       kobject_uevent(&mem->dev.kobj, KOBJ_ONLINE);
+                       break;
+               default:
+                       break;
+               }
        }
-out:
        return ret;
 }
 
@@ -315,8 +352,8 @@ static int memory_block_change_state(struct memory_block *mem,
        int ret;
 
        mutex_lock(&mem->state_mutex);
-       ret = __memory_block_change_state(mem, to_state, from_state_req,
-                                         online_type);
+       ret = __memory_block_change_state_uevent(mem, to_state, from_state_req,
+                                                online_type);
        mutex_unlock(&mem->state_mutex);
 
        return ret;
@@ -326,22 +363,34 @@ store_mem_state(struct device *dev,
                struct device_attribute *attr, const char *buf, size_t count)
 {
        struct memory_block *mem;
+       bool offline;
        int ret = -EINVAL;
 
        mem = container_of(dev, struct memory_block, dev);
 
-       if (!strncmp(buf, "online_kernel", min_t(int, count, 13)))
+       lock_device_hotplug();
+
+       if (!strncmp(buf, "online_kernel", min_t(int, count, 13))) {
+               offline = false;
                ret = memory_block_change_state(mem, MEM_ONLINE,
                                                MEM_OFFLINE, ONLINE_KERNEL);
-       else if (!strncmp(buf, "online_movable", min_t(int, count, 14)))
+       } else if (!strncmp(buf, "online_movable", min_t(int, count, 14))) {
+               offline = false;
                ret = memory_block_change_state(mem, MEM_ONLINE,
                                                MEM_OFFLINE, ONLINE_MOVABLE);
-       else if (!strncmp(buf, "online", min_t(int, count, 6)))
+       } else if (!strncmp(buf, "online", min_t(int, count, 6))) {
+               offline = false;
                ret = memory_block_change_state(mem, MEM_ONLINE,
                                                MEM_OFFLINE, ONLINE_KEEP);
-       else if(!strncmp(buf, "offline", min_t(int, count, 7)))
+       } else if(!strncmp(buf, "offline", min_t(int, count, 7))) {
+               offline = true;
                ret = memory_block_change_state(mem, MEM_OFFLINE,
                                                MEM_ONLINE, -1);
+       }
+       if (!ret)
+               dev->offline = offline;
+
+       unlock_device_hotplug();
 
        if (ret)
                return ret;
@@ -679,21 +728,6 @@ int unregister_memory_section(struct mem_section *section)
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 
-/*
- * offline one memory block. If the memory block has been offlined, do nothing.
- */
-int offline_memory_block(struct memory_block *mem)
-{
-       int ret = 0;
-
-       mutex_lock(&mem->state_mutex);
-       if (mem->state != MEM_OFFLINE)
-               ret = __memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE, -1);
-       mutex_unlock(&mem->state_mutex);
-
-       return ret;
-}
-
 /* return true if the memory block is offlined, otherwise, return false */
 bool is_memblock_offlined(struct memory_block *mem)
 {
index edc089e9d0c42028aa93a208dde52dea9224df53..b8efacf01d694cb50a07115cc0a79a57d638c3e4 100644 (file)
@@ -1034,4 +1034,11 @@ static const struct x86_cpu_id acpi_cpufreq_ids[] = {
 };
 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
 
+static const struct acpi_device_id processor_device_ids[] = {
+       {ACPI_PROCESSOR_OBJECT_HID, },
+       {ACPI_PROCESSOR_DEVICE_HID, },
+       {},
+};
+MODULE_DEVICE_TABLE(acpi, processor_device_ids);
+
 MODULE_ALIAS("acpi");
index c13c919ab99e9803b2ebe18d36eb93ab98bf6076..cf0817a555e4a2065bce03af547f6cd7a1422404 100644 (file)
@@ -63,13 +63,6 @@ acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld
 #define ACPI_BUS_FILE_ROOT     "acpi"
 extern struct proc_dir_entry *acpi_root_dir;
 
-enum acpi_bus_removal_type {
-       ACPI_BUS_REMOVAL_NORMAL = 0,
-       ACPI_BUS_REMOVAL_EJECT,
-       ACPI_BUS_REMOVAL_SUPRISE,
-       ACPI_BUS_REMOVAL_TYPE_COUNT
-};
-
 enum acpi_bus_device_type {
        ACPI_BUS_TYPE_DEVICE = 0,
        ACPI_BUS_TYPE_POWER,
@@ -286,6 +279,7 @@ struct acpi_device_physical_node {
        u8 node_id;
        struct list_head node;
        struct device *dev;
+       bool put_online:1;
 };
 
 /* set maximum of physical nodes to 32 for expansibility */
@@ -310,7 +304,6 @@ struct acpi_device {
        struct acpi_driver *driver;
        void *driver_data;
        struct device dev;
-       enum acpi_bus_removal_type removal_type;        /* indicate for different removal type */
        u8 physical_node_count;
        struct list_head physical_node_list;
        struct mutex physical_node_lock;
index ea69367fdd3bbafaf1775da248c7cc998c47fba8..66096d06925e417d70d6b8974a00a035d05ef1d8 100644 (file)
@@ -6,6 +6,10 @@
 #include <linux/thermal.h>
 #include <asm/acpi.h>
 
+#define ACPI_PROCESSOR_CLASS           "processor"
+#define ACPI_PROCESSOR_DEVICE_NAME     "Processor"
+#define ACPI_PROCESSOR_DEVICE_HID      "ACPI0007"
+
 #define ACPI_PROCESSOR_BUSY_METRIC     10
 
 #define ACPI_PROCESSOR_MAX_POWER       8
@@ -207,6 +211,7 @@ struct acpi_processor {
        struct acpi_processor_throttling throttling;
        struct acpi_processor_limit limit;
        struct thermal_cooling_device *cdev;
+       struct device *dev; /* Processor device. */
 };
 
 struct acpi_processor_errata {
index 17b5b596764100ae14400437b86e84b0c068291f..353ba256f3681e4f6ddd8b18b9feba61b1d98cec 100644 (file)
@@ -352,8 +352,7 @@ extern acpi_status acpi_pci_osc_control_set(acpi_handle handle,
 
 /* Enable _OST when all relevant hotplug operations are enabled */
 #if defined(CONFIG_ACPI_HOTPLUG_CPU) &&                        \
-       (defined(CONFIG_ACPI_HOTPLUG_MEMORY) ||         \
-        defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)) && \
+       defined(CONFIG_ACPI_HOTPLUG_MEMORY) &&          \
        defined(CONFIG_ACPI_CONTAINER)
 #define ACPI_HOTPLUG_OST
 #endif
index c0a12612532512bab2f792fba4b40580c48b13dd..eeb33315514c332ddf83b9fcf4183a580555bab6 100644 (file)
@@ -71,6 +71,10 @@ extern void bus_remove_file(struct bus_type *, struct bus_attribute *);
  *             the specific driver's probe to initial the matched device.
  * @remove:    Called when a device removed from this bus.
  * @shutdown:  Called at shut-down time to quiesce the device.
+ *
+ * @online:    Called to put the device back online (after offlining it).
+ * @offline:   Called to put the device offline for hot-removal. May fail.
+ *
  * @suspend:   Called when a device on this bus wants to go to sleep mode.
  * @resume:    Called to bring a device on this bus out of sleep mode.
  * @pm:                Power management operations of this bus, callback the specific
@@ -104,6 +108,9 @@ struct bus_type {
        int (*remove)(struct device *dev);
        void (*shutdown)(struct device *dev);
 
+       int (*online)(struct device *dev);
+       int (*offline)(struct device *dev);
+
        int (*suspend)(struct device *dev, pm_message_t state);
        int (*resume)(struct device *dev);
 
@@ -648,6 +655,8 @@ struct acpi_dev_node {
  * @release:   Callback to free the device after all references have
  *             gone away. This should be set by the allocator of the
  *             device (i.e. the bus driver that discovered the device).
+ * @offline_disabled: If set, the device is permanently online.
+ * @offline:   Set after successful invocation of bus type's .offline().
  *
  * At the lowest level, every device in a Linux system is represented by an
  * instance of struct device. The device structure contains the information
@@ -720,6 +729,9 @@ struct device {
 
        void    (*release)(struct device *dev);
        struct iommu_group      *iommu_group;
+
+       bool                    offline_disabled:1;
+       bool                    offline:1;
 };
 
 static inline struct device *kobj_to_dev(struct kobject *kobj)
@@ -856,6 +868,15 @@ extern const char *device_get_devnode(struct device *dev,
 extern void *dev_get_drvdata(const struct device *dev);
 extern int dev_set_drvdata(struct device *dev, void *data);
 
+static inline bool device_supports_offline(struct device *dev)
+{
+       return dev->bus && dev->bus->offline && dev->bus->online;
+}
+
+extern void lock_device_hotplug(void);
+extern void unlock_device_hotplug(void);
+extern int device_offline(struct device *dev);
+extern int device_online(struct device *dev);
 /*
  * Root device objects for grouping under /sys/devices
  */
index 3e622c6109255650896ce67e141403ec1d36479e..dd38e62b84d2824ecf1e412cdd7fbb908dac675f 100644 (file)
@@ -234,6 +234,8 @@ static inline void unlock_memory_hotplug(void) {}
 
 extern int is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
 extern void try_offline_node(int nid);
+extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
+extern void remove_memory(int nid, u64 start, u64 size);
 
 #else
 static inline int is_mem_section_removable(unsigned long pfn,
@@ -243,15 +245,23 @@ static inline int is_mem_section_removable(unsigned long pfn,
 }
 
 static inline void try_offline_node(int nid) {}
+
+static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
+{
+       return -EINVAL;
+}
+
+static inline void remove_memory(int nid, u64 start, u64 size) {}
 #endif /* CONFIG_MEMORY_HOTREMOVE */
 
+extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
+               void *arg, int (*func)(struct memory_block *, void *));
 extern int mem_online_node(int nid);
 extern int add_memory(int nid, u64 start, u64 size);
 extern int arch_add_memory(int nid, u64 start, u64 size);
 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
-extern int offline_memory_block(struct memory_block *mem);
 extern bool is_memblock_offlined(struct memory_block *mem);
-extern int remove_memory(int nid, u64 start, u64 size);
+extern void remove_memory(int nid, u64 start, u64 size);
 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
                                                                int nr_pages);
 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms);
index 1ad92b46753edfe8d9f54fae81c5f3aa15b34110..081b4d654ed6d68f5538a831719de7331110fa2f 100644 (file)
@@ -1621,6 +1621,7 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
 {
        return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ);
 }
+#endif /* CONFIG_MEMORY_HOTREMOVE */
 
 /**
  * walk_memory_range - walks through all mem sections in [start_pfn, end_pfn)
@@ -1634,7 +1635,7 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
  *
  * Returns the return value of func.
  */
-static int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
+int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
                void *arg, int (*func)(struct memory_block *, void *))
 {
        struct memory_block *mem = NULL;
@@ -1671,24 +1672,7 @@ static int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
        return 0;
 }
 
-/**
- * offline_memory_block_cb - callback function for offlining memory block
- * @mem: the memory block to be offlined
- * @arg: buffer to hold error msg
- *
- * Always return 0, and put the error msg in arg if any.
- */
-static int offline_memory_block_cb(struct memory_block *mem, void *arg)
-{
-       int *ret = arg;
-       int error = offline_memory_block(mem);
-
-       if (error != 0 && *ret == 0)
-               *ret = error;
-
-       return 0;
-}
-
+#ifdef CONFIG_MEMORY_HOTREMOVE
 static int is_memblock_offlined_cb(struct memory_block *mem, void *arg)
 {
        int ret = !is_memblock_offlined(mem);
@@ -1814,54 +1798,22 @@ void try_offline_node(int nid)
 }
 EXPORT_SYMBOL(try_offline_node);
 
-int __ref remove_memory(int nid, u64 start, u64 size)
+void __ref remove_memory(int nid, u64 start, u64 size)
 {
-       unsigned long start_pfn, end_pfn;
-       int ret = 0;
-       int retry = 1;
-
-       start_pfn = PFN_DOWN(start);
-       end_pfn = PFN_UP(start + size - 1);
-
-       /*
-        * When CONFIG_MEMCG is on, one memory block may be used by other
-        * blocks to store page cgroup when onlining pages. But we don't know
-        * in what order pages are onlined. So we iterate twice to offline
-        * memory:
-        * 1st iterate: offline every non primary memory block.
-        * 2nd iterate: offline primary (i.e. first added) memory block.
-        */
-repeat:
-       walk_memory_range(start_pfn, end_pfn, &ret,
-                         offline_memory_block_cb);
-       if (ret) {
-               if (!retry)
-                       return ret;
-
-               retry = 0;
-               ret = 0;
-               goto repeat;
-       }
+       int ret;
 
        lock_memory_hotplug();
 
        /*
-        * we have offlined all memory blocks like this:
-        *   1. lock memory hotplug
-        *   2. offline a memory block
-        *   3. unlock memory hotplug
-        *
-        * repeat step1-3 to offline the memory block. All memory blocks
-        * must be offlined before removing memory. But we don't hold the
-        * lock in the whole operation. So we should check whether all
-        * memory blocks are offlined.
+        * All memory blocks must be offlined before removing memory.  Check
+        * whether all memory blocks in question are offline and trigger a BUG()
+        * if this is not the case.
         */
-
-       ret = walk_memory_range(start_pfn, end_pfn, NULL,
+       ret = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL,
                                is_memblock_offlined_cb);
        if (ret) {
                unlock_memory_hotplug();
-               return ret;
+               BUG();
        }
 
        /* remove memmap entry */
@@ -1872,17 +1824,6 @@ repeat:
        try_offline_node(nid);
 
        unlock_memory_hotplug();
-
-       return 0;
 }
-#else
-int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
-{
-       return -EINVAL;
-}
-int remove_memory(int nid, u64 start, u64 size)
-{
-       return -EINVAL;
-}
-#endif /* CONFIG_MEMORY_HOTREMOVE */
 EXPORT_SYMBOL_GPL(remove_memory);
+#endif /* CONFIG_MEMORY_HOTREMOVE */