Merge tag 'stable/for-linus-3.9-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen update from Konrad Rzeszutek Wilk:
 "This has two new ACPI drivers for Xen - a physical CPU offline/online
  and a memory hotplug.  The way this works is that ACPI kicks the
  drivers and they make the appropiate hypercall to the hypervisor to
  tell it that there is a new CPU or memory.  There also some changes to
  the Xen ARM ABIs and couple of fixes.  One particularly nasty bug in
  the Xen PV spinlock code was fixed by Stefan Bader - and has been
  there since the 2.6.32!

  Features:
   - Xen ACPI memory and CPU hotplug drivers - allowing Xen hypervisor
     to be aware of new CPU and new DIMMs
   - Cleanups
  Bug-fixes:
   - Fixes a long-standing bug in the PV spinlock wherein we did not
     kick VCPUs that were in a tight loop.
   - Fixes in the error paths for the event channel machinery"

Fix up a few semantic conflicts with the ACPI interface changes in
drivers/xen/xen-acpi-{cpu,mem}hotplug.c.

* tag 'stable/for-linus-3.9-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: event channel arrays are xen_ulong_t and not unsigned long
  xen: Send spinlock IPI to all waiters
  xen: introduce xen_remap, use it instead of ioremap
  xen: close evtchn port if binding to irq fails
  xen-evtchn: correct comment and error output
  xen/tmem: Add missing %s in the printk statement.
  xen/acpi: move xen_acpi_get_pxm under CONFIG_XEN_DOM0
  xen/acpi: ACPI cpu hotplug
  xen/acpi: Move xen_acpi_get_pxm to Xen's acpi.h
  xen/stub: driver for CPU hotplug
  xen/acpi: ACPI memory hotplug
  xen/stub: driver for memory hotplug
  xen: implement updated XENMEM_add_to_physmap_range ABI
  xen/smp: Move the common CPU init code a bit to prep for PVH patch.

1 files changed, 471 insertions, 0 deletions

diff --git a/drivers/xen/xen-acpi-cpuhotplug.c b/drivers/xen/xen-acpi-cpuhotplug.c
new file mode 100644
index 000000000000..757827966e34
--- /dev/null
+++ b/drivers/xen/xen-acpi-cpuhotplug.c
@@ -0,0 +1,471 @@
+/*
+ * Copyright (C) 2012 Intel Corporation
+ *    Author: Liu Jinsong <jinsong.liu@intel.com>
+ *    Author: Jiang Yunhong <yunhong.jiang@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/cpu.h>
+#include <linux/acpi.h>
+#include <linux/uaccess.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+#include <acpi/processor.h>
+
+#include <xen/acpi.h>
+#include <xen/interface/platform.h>
+#include <asm/xen/hypercall.h>
+
+#define PREFIX "ACPI:xen_cpu_hotplug:"
+
+#define INSTALL_NOTIFY_HANDLER          0
+#define UNINSTALL_NOTIFY_HANDLER        1
+
+static acpi_status xen_acpi_cpu_hotadd(struct acpi_processor *pr);
+
+/* --------------------------------------------------------------------------
+                                Driver Interface
+-------------------------------------------------------------------------- */
+
+static int xen_acpi_processor_enable(struct acpi_device *device)
+{
+        acpi_status status = 0;
+        unsigned long long value;
+        union acpi_object object = { 0 };
+        struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
+        struct acpi_processor *pr;
+
+        pr = acpi_driver_data(device);
+        if (!pr) {
+                pr_err(PREFIX "Cannot find driver data\n");
+                return -EINVAL;
+        }
+
+        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)) {
+                        pr_err(PREFIX "Evaluating processor object\n");
+                        return -ENODEV;
+                }
+
+                pr->acpi_id = object.processor.proc_id;
+        } else {
+                /* Declared with "Device" statement; match _UID */
+                status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
+                                                NULL, &value);
+                if (ACPI_FAILURE(status)) {
+                        pr_err(PREFIX "Evaluating processor _UID\n");
+                        return -ENODEV;
+                }
+
+                pr->acpi_id = value;
+        }
+
+        pr->id = xen_pcpu_id(pr->acpi_id);
+
+        if ((int)pr->id < 0)
+                /* This cpu is not presented at hypervisor, try to hotadd it */
+                if (ACPI_FAILURE(xen_acpi_cpu_hotadd(pr))) {
+                        pr_err(PREFIX "Hotadd CPU (acpi_id = %d) failed.\n",
+                                        pr->acpi_id);
+                        return -ENODEV;
+                }
+
+        return 0;
+}
+
+static int __cpuinit xen_acpi_processor_add(struct acpi_device *device)
+{
+        int ret;
+        struct acpi_processor *pr;
+
+        if (!device)
+                return -EINVAL;
+
+        pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
+        if (!pr)
+                return -ENOMEM;
+
+        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;
+
+        ret = xen_acpi_processor_enable(device);
+        if (ret)
+                pr_err(PREFIX "Error when enabling Xen processor\n");
+
+        return ret;
+}
+
+static int xen_acpi_processor_remove(struct acpi_device *device)
+{
+        struct acpi_processor *pr;
+
+        if (!device)
+                return -EINVAL;
+
+        pr = acpi_driver_data(device);
+        if (!pr)
+                return -EINVAL;
+
+        kfree(pr);
+        return 0;
+}
+
+/*--------------------------------------------------------------
+                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)
+                pr_info(PREFIX "Processor does not support hot plug\n");
+        else
+                pr_info(PREFIX "Processor Device is not present");
+        return 0;
+}
+
+static int xen_apic_id(acpi_handle handle)
+{
+        struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+        union acpi_object *obj;
+        struct acpi_madt_local_apic *lapic;
+        int apic_id;
+
+        if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
+                return -EINVAL;
+
+        if (!buffer.length || !buffer.pointer)
+                return -EINVAL;
+
+        obj = buffer.pointer;
+        if (obj->type != ACPI_TYPE_BUFFER ||
+            obj->buffer.length < sizeof(*lapic)) {
+                kfree(buffer.pointer);
+                return -EINVAL;
+        }
+
+        lapic = (struct acpi_madt_local_apic *)obj->buffer.pointer;
+
+        if (lapic->header.type != ACPI_MADT_TYPE_LOCAL_APIC ||
+            !(lapic->lapic_flags & ACPI_MADT_ENABLED)) {
+                kfree(buffer.pointer);
+                return -EINVAL;
+        }
+
+        apic_id = (uint32_t)lapic->id;
+        kfree(buffer.pointer);
+        buffer.length = ACPI_ALLOCATE_BUFFER;
+        buffer.pointer = NULL;
+
+        return apic_id;
+}
+
+static int xen_hotadd_cpu(struct acpi_processor *pr)
+{
+        int cpu_id, apic_id, pxm;
+        struct xen_platform_op op;
+
+        apic_id = xen_apic_id(pr->handle);
+        if (apic_id < 0) {
+                pr_err(PREFIX "Failed to get apic_id for acpi_id %d\n",
+                                pr->acpi_id);
+                return -ENODEV;
+        }
+
+        pxm = xen_acpi_get_pxm(pr->handle);
+        if (pxm < 0) {
+                pr_err(PREFIX "Failed to get _PXM for acpi_id %d\n",
+                                pr->acpi_id);
+                return pxm;
+        }
+
+        op.cmd = XENPF_cpu_hotadd;
+        op.u.cpu_add.apic_id = apic_id;
+        op.u.cpu_add.acpi_id = pr->acpi_id;
+        op.u.cpu_add.pxm = pxm;
+
+        cpu_id = HYPERVISOR_dom0_op(&op);
+        if (cpu_id < 0)
+                pr_err(PREFIX "Failed to hotadd CPU for acpi_id %d\n",
+                                pr->acpi_id);
+
+        return cpu_id;
+}
+
+static acpi_status xen_acpi_cpu_hotadd(struct acpi_processor *pr)
+{
+        if (!is_processor_present(pr->handle))
+                return AE_ERROR;
+
+        pr->id = xen_hotadd_cpu(pr);
+        if ((int)pr->id < 0)
+                return AE_ERROR;
+
+        /*
+         * Sync with Xen hypervisor, providing new /sys/.../xen_cpuX
+         * interface after cpu hotadded.
+         */
+        xen_pcpu_hotplug_sync();
+
+        return AE_OK;
+}
+
+static
+int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
+{
+        acpi_handle phandle;
+        struct acpi_device *pdev;
+
+        if (acpi_get_parent(handle, &phandle))
+                return -ENODEV;
+
+        if (acpi_bus_get_device(phandle, &pdev))
+                return -ENODEV;
+
+        if (acpi_bus_scan(handle))
+                return -ENODEV;
+
+        return 0;
+}
+
+static int acpi_processor_device_remove(struct acpi_device *device)
+{
+        pr_debug(PREFIX "Xen does not support CPU hotremove\n");
+
+        return -ENOSYS;
+}
+
+static void acpi_processor_hotplug_notify(acpi_handle handle,
+                                          u32 event, void *data)
+{
+        struct acpi_processor *pr;
+        struct acpi_device *device = NULL;
+        u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
+        int result;
+
+        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_processor_device_add(handle, &device);
+                if (result) {
+                        pr_err(PREFIX "Unable to add the device\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)) {
+                        pr_err(PREFIX "Device don't exist, dropping EJECT\n");
+                        break;
+                }
+                pr = acpi_driver_data(device);
+                if (!pr) {
+                        pr_err(PREFIX "Driver data is NULL, dropping EJECT\n");
+                        break;
+                }
+
+                /*
+                 * TBD: implement acpi_processor_device_remove if Xen support
+                 * CPU hotremove in the future.
+                 */
+                acpi_processor_device_remove(device);
+                break;
+
+        default:
+                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                  "Unsupported event [0x%x]\n", event));
+
+                /* non-hotplug event; possibly handled by other handler */
+                return;
+        }
+
+        (void) acpi_evaluate_hotplug_ost(handle, event, ost_code, NULL);
+        return;
+}
+
+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
+void acpi_processor_install_hotplug_notify(void)
+{
+        int action = INSTALL_NOTIFY_HANDLER;
+        acpi_walk_namespace(ACPI_TYPE_ANY,
+                            ACPI_ROOT_OBJECT,
+                            ACPI_UINT32_MAX,
+                            processor_walk_namespace_cb, NULL, &action, NULL);
+}
+
+static
+void acpi_processor_uninstall_hotplug_notify(void)
+{
+        int action = UNINSTALL_NOTIFY_HANDLER;
+        acpi_walk_namespace(ACPI_TYPE_ANY,
+                            ACPI_ROOT_OBJECT,
+                            ACPI_UINT32_MAX,
+                            processor_walk_namespace_cb, NULL, &action, NULL);
+}
+
+static const struct acpi_device_id processor_device_ids[] = {
+        {ACPI_PROCESSOR_OBJECT_HID, 0},
+        {ACPI_PROCESSOR_DEVICE_HID, 0},
+        {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, processor_device_ids);
+
+static struct acpi_driver xen_acpi_processor_driver = {
+        .name = "processor",
+        .class = ACPI_PROCESSOR_CLASS,
+        .ids = processor_device_ids,
+        .ops = {
+                .add = xen_acpi_processor_add,
+                .remove = xen_acpi_processor_remove,
+                },
+};
+
+static int __init xen_acpi_processor_init(void)
+{
+        int result = 0;
+
+        if (!xen_initial_domain())
+                return -ENODEV;
+
+        /* unregister the stub which only used to reserve driver space */
+        xen_stub_processor_exit();
+
+        result = acpi_bus_register_driver(&xen_acpi_processor_driver);
+        if (result < 0) {
+                xen_stub_processor_init();
+                return result;
+        }
+
+        acpi_processor_install_hotplug_notify();
+        return 0;
+}
+
+static void __exit xen_acpi_processor_exit(void)
+{
+        if (!xen_initial_domain())
+                return;
+
+        acpi_processor_uninstall_hotplug_notify();
+
+        acpi_bus_unregister_driver(&xen_acpi_processor_driver);
+
+        /*
+         * stub reserve space again to prevent any chance of native
+         * driver loading.
+         */
+        xen_stub_processor_init();
+        return;
+}
+
+module_init(xen_acpi_processor_init);
+module_exit(xen_acpi_processor_exit);
+ACPI_MODULE_NAME("xen-acpi-cpuhotplug");
+MODULE_AUTHOR("Liu Jinsong <jinsong.liu@intel.com>");
+MODULE_DESCRIPTION("Xen Hotplug CPU Driver");
+MODULE_LICENSE("GPL");