diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-24 16:06:13 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-24 16:18:31 -0800 |
commit | 77be36de8b07027a70fbc8f02703ccd76cd16d09 (patch) | |
tree | e2310718e39cb0dcfe93942d4c990df9154a7ecd /drivers/xen/xen-acpi-memhotplug.c | |
parent | 89f883372fa60f604d136924baf3e89ff1870e9e (diff) | |
parent | c81611c4e96f595a80d8be9367c385d2c116428b (diff) | |
download | linux-77be36de8b07027a70fbc8f02703ccd76cd16d09.tar.gz linux-77be36de8b07027a70fbc8f02703ccd76cd16d09.tar.bz2 linux-77be36de8b07027a70fbc8f02703ccd76cd16d09.zip |
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.
Diffstat (limited to 'drivers/xen/xen-acpi-memhotplug.c')
-rw-r--r-- | drivers/xen/xen-acpi-memhotplug.c | 483 |
1 files changed, 483 insertions, 0 deletions
diff --git a/drivers/xen/xen-acpi-memhotplug.c b/drivers/xen/xen-acpi-memhotplug.c new file mode 100644 index 000000000000..853b12dba5bb --- /dev/null +++ b/drivers/xen/xen-acpi-memhotplug.c @@ -0,0 +1,483 @@ +/* + * 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/acpi.h> +#include <acpi/acpi_drivers.h> +#include <xen/acpi.h> +#include <xen/interface/platform.h> +#include <asm/xen/hypercall.h> + +#define PREFIX "ACPI:xen_memory_hotplug:" + +struct acpi_memory_info { + struct list_head list; + u64 start_addr; /* Memory Range start physical addr */ + u64 length; /* Memory Range length */ + unsigned short caching; /* memory cache attribute */ + unsigned short write_protect; /* memory read/write attribute */ + /* copied from buffer getting from _CRS */ + unsigned int enabled:1; +}; + +struct acpi_memory_device { + struct acpi_device *device; + struct list_head res_list; +}; + +static bool acpi_hotmem_initialized __read_mostly; + +static int xen_hotadd_memory(int pxm, struct acpi_memory_info *info) +{ + int rc; + struct xen_platform_op op; + + op.cmd = XENPF_mem_hotadd; + op.u.mem_add.spfn = info->start_addr >> PAGE_SHIFT; + op.u.mem_add.epfn = (info->start_addr + info->length) >> PAGE_SHIFT; + op.u.mem_add.pxm = pxm; + + rc = HYPERVISOR_dom0_op(&op); + if (rc) + pr_err(PREFIX "Xen Hotplug Memory Add failed on " + "0x%lx -> 0x%lx, _PXM: %d, error: %d\n", + (unsigned long)info->start_addr, + (unsigned long)(info->start_addr + info->length), + pxm, rc); + + return rc; +} + +static int xen_acpi_memory_enable_device(struct acpi_memory_device *mem_device) +{ + int pxm, result; + int num_enabled = 0; + struct acpi_memory_info *info; + + if (!mem_device) + return -EINVAL; + + pxm = xen_acpi_get_pxm(mem_device->device->handle); + if (pxm < 0) + return pxm; + + list_for_each_entry(info, &mem_device->res_list, list) { + if (info->enabled) { /* just sanity check...*/ + num_enabled++; + continue; + } + + if (!info->length) + continue; + + result = xen_hotadd_memory(pxm, info); + if (result) + continue; + info->enabled = 1; + num_enabled++; + } + + if (!num_enabled) + return -ENODEV; + + return 0; +} + +static acpi_status +acpi_memory_get_resource(struct acpi_resource *resource, void *context) +{ + struct acpi_memory_device *mem_device = context; + struct acpi_resource_address64 address64; + struct acpi_memory_info *info, *new; + acpi_status status; + + status = acpi_resource_to_address64(resource, &address64); + if (ACPI_FAILURE(status) || + (address64.resource_type != ACPI_MEMORY_RANGE)) + return AE_OK; + + list_for_each_entry(info, &mem_device->res_list, list) { + if ((info->caching == address64.info.mem.caching) && + (info->write_protect == address64.info.mem.write_protect) && + (info->start_addr + info->length == address64.minimum)) { + info->length += address64.address_length; + return AE_OK; + } + } + + new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL); + if (!new) + return AE_ERROR; + + INIT_LIST_HEAD(&new->list); + new->caching = address64.info.mem.caching; + new->write_protect = address64.info.mem.write_protect; + new->start_addr = address64.minimum; + new->length = address64.address_length; + list_add_tail(&new->list, &mem_device->res_list); + + return AE_OK; +} + +static int +acpi_memory_get_device_resources(struct acpi_memory_device *mem_device) +{ + acpi_status status; + struct acpi_memory_info *info, *n; + + if (!list_empty(&mem_device->res_list)) + return 0; + + status = acpi_walk_resources(mem_device->device->handle, + METHOD_NAME__CRS, acpi_memory_get_resource, mem_device); + + if (ACPI_FAILURE(status)) { + list_for_each_entry_safe(info, n, &mem_device->res_list, list) + kfree(info); + INIT_LIST_HEAD(&mem_device->res_list); + return -EINVAL; + } + + return 0; +} + +static int +acpi_memory_get_device(acpi_handle handle, + struct acpi_memory_device **mem_device) +{ + acpi_status status; + acpi_handle phandle; + struct acpi_device *device = NULL; + struct acpi_device *pdevice = NULL; + int result; + + if (!acpi_bus_get_device(handle, &device) && device) + goto end; + + status = acpi_get_parent(handle, &phandle); + if (ACPI_FAILURE(status)) { + pr_warn(PREFIX "Cannot find acpi parent\n"); + return -EINVAL; + } + + /* Get the parent device */ + result = acpi_bus_get_device(phandle, &pdevice); + if (result) { + pr_warn(PREFIX "Cannot get acpi bus device\n"); + return -EINVAL; + } + + /* + * Now add the notified device. This creates the acpi_device + * and invokes .add function + */ + result = acpi_bus_scan(handle); + if (result) { + pr_warn(PREFIX "Cannot add acpi bus\n"); + return -EINVAL; + } + +end: + *mem_device = acpi_driver_data(device); + if (!(*mem_device)) { + pr_err(PREFIX "Driver data not found\n"); + return -ENODEV; + } + + return 0; +} + +static int acpi_memory_check_device(struct acpi_memory_device *mem_device) +{ + unsigned long long current_status; + + /* Get device present/absent information from the _STA */ + if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle, + "_STA", NULL, ¤t_status))) + return -ENODEV; + /* + * Check for device status. Device should be + * present/enabled/functioning. + */ + if (!((current_status & ACPI_STA_DEVICE_PRESENT) + && (current_status & ACPI_STA_DEVICE_ENABLED) + && (current_status & ACPI_STA_DEVICE_FUNCTIONING))) + return -ENODEV; + + return 0; +} + +static int acpi_memory_disable_device(struct acpi_memory_device *mem_device) +{ + pr_debug(PREFIX "Xen does not support memory hotremove\n"); + + return -ENOSYS; +} + +static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data) +{ + struct acpi_memory_device *mem_device; + struct acpi_device *device; + u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */ + + switch (event) { + case ACPI_NOTIFY_BUS_CHECK: + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "\nReceived BUS CHECK notification for device\n")); + /* Fall Through */ + case ACPI_NOTIFY_DEVICE_CHECK: + if (event == ACPI_NOTIFY_DEVICE_CHECK) + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "\nReceived DEVICE CHECK notification for device\n")); + + if (acpi_memory_get_device(handle, &mem_device)) { + pr_err(PREFIX "Cannot find driver data\n"); + break; + } + + ost_code = ACPI_OST_SC_SUCCESS; + break; + + case ACPI_NOTIFY_EJECT_REQUEST: + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "\nReceived EJECT REQUEST notification for device\n")); + + if (acpi_bus_get_device(handle, &device)) { + pr_err(PREFIX "Device doesn't exist\n"); + break; + } + mem_device = acpi_driver_data(device); + if (!mem_device) { + pr_err(PREFIX "Driver Data is NULL\n"); + break; + } + + /* + * TBD: implement acpi_memory_disable_device and invoke + * acpi_bus_remove if Xen support hotremove in the future + */ + acpi_memory_disable_device(mem_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 int xen_acpi_memory_device_add(struct acpi_device *device) +{ + int result; + struct acpi_memory_device *mem_device = NULL; + + + if (!device) + return -EINVAL; + + mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL); + if (!mem_device) + return -ENOMEM; + + INIT_LIST_HEAD(&mem_device->res_list); + mem_device->device = device; + sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME); + sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS); + device->driver_data = mem_device; + + /* Get the range from the _CRS */ + result = acpi_memory_get_device_resources(mem_device); + if (result) { + kfree(mem_device); + return result; + } + + /* + * For booting existed memory devices, early boot code has recognized + * memory area by EFI/E820. If DSDT shows these memory devices on boot, + * hotplug is not necessary for them. + * For hot-added memory devices during runtime, it need hypercall to + * Xen hypervisor to add memory. + */ + if (!acpi_hotmem_initialized) + return 0; + + if (!acpi_memory_check_device(mem_device)) + result = xen_acpi_memory_enable_device(mem_device); + + return result; +} + +static int xen_acpi_memory_device_remove(struct acpi_device *device) +{ + struct acpi_memory_device *mem_device = NULL; + + if (!device || !acpi_driver_data(device)) + return -EINVAL; + + mem_device = acpi_driver_data(device); + kfree(mem_device); + + return 0; +} + +/* + * Helper function to check for memory device + */ +static acpi_status is_memory_device(acpi_handle handle) +{ + char *hardware_id; + acpi_status status; + struct acpi_device_info *info; + + status = acpi_get_object_info(handle, &info); + if (ACPI_FAILURE(status)) + return status; + + if (!(info->valid & ACPI_VALID_HID)) { + kfree(info); + return AE_ERROR; + } + + hardware_id = info->hardware_id.string; + if ((hardware_id == NULL) || + (strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID))) + status = AE_ERROR; + + kfree(info); + return status; +} + +static acpi_status +acpi_memory_register_notify_handler(acpi_handle handle, + u32 level, void *ctxt, void **retv) +{ + acpi_status status; + + status = is_memory_device(handle); + if (ACPI_FAILURE(status)) + return AE_OK; /* continue */ + + status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY, + acpi_memory_device_notify, NULL); + /* continue */ + return AE_OK; +} + +static acpi_status +acpi_memory_deregister_notify_handler(acpi_handle handle, + u32 level, void *ctxt, void **retv) +{ + acpi_status status; + + status = is_memory_device(handle); + if (ACPI_FAILURE(status)) + return AE_OK; /* continue */ + + status = acpi_remove_notify_handler(handle, + ACPI_SYSTEM_NOTIFY, + acpi_memory_device_notify); + + return AE_OK; /* continue */ +} + +static const struct acpi_device_id memory_device_ids[] = { + {ACPI_MEMORY_DEVICE_HID, 0}, + {"", 0}, +}; +MODULE_DEVICE_TABLE(acpi, memory_device_ids); + +static struct acpi_driver xen_acpi_memory_device_driver = { + .name = "acpi_memhotplug", + .class = ACPI_MEMORY_DEVICE_CLASS, + .ids = memory_device_ids, + .ops = { + .add = xen_acpi_memory_device_add, + .remove = xen_acpi_memory_device_remove, + }, +}; + +static int __init xen_acpi_memory_device_init(void) +{ + int result; + acpi_status status; + + if (!xen_initial_domain()) + return -ENODEV; + + /* unregister the stub which only used to reserve driver space */ + xen_stub_memory_device_exit(); + + result = acpi_bus_register_driver(&xen_acpi_memory_device_driver); + if (result < 0) { + xen_stub_memory_device_init(); + return -ENODEV; + } + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, + ACPI_UINT32_MAX, + acpi_memory_register_notify_handler, + NULL, NULL, NULL); + + if (ACPI_FAILURE(status)) { + pr_warn(PREFIX "walk_namespace failed\n"); + acpi_bus_unregister_driver(&xen_acpi_memory_device_driver); + xen_stub_memory_device_init(); + return -ENODEV; + } + + acpi_hotmem_initialized = true; + return 0; +} + +static void __exit xen_acpi_memory_device_exit(void) +{ + acpi_status status; + + if (!xen_initial_domain()) + return; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, + ACPI_UINT32_MAX, + acpi_memory_deregister_notify_handler, + NULL, NULL, NULL); + if (ACPI_FAILURE(status)) + pr_warn(PREFIX "walk_namespace failed\n"); + + acpi_bus_unregister_driver(&xen_acpi_memory_device_driver); + + /* + * stub reserve space again to prevent any chance of native + * driver loading. + */ + xen_stub_memory_device_init(); + return; +} + +module_init(xen_acpi_memory_device_init); +module_exit(xen_acpi_memory_device_exit); +ACPI_MODULE_NAME("xen-acpi-memhotplug"); +MODULE_AUTHOR("Liu Jinsong <jinsong.liu@intel.com>"); +MODULE_DESCRIPTION("Xen Hotplug Mem Driver"); +MODULE_LICENSE("GPL"); |