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|
/*
* 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/acpi.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.address.minimum)) {
info->length += address64.address.address_length;
return AE_OK;
}
}
new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
if (!new)
return AE_ERROR;
INIT_LIST_HEAD(&new->list);
new->caching = address64.info.mem.caching;
new->write_protect = address64.info.mem.write_protect;
new->start_addr = address64.address.minimum;
new->length = address64.address.address_length;
list_add_tail(&new->list, &mem_device->res_list);
return AE_OK;
}
static 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)
{
struct acpi_device *device = NULL;
int result = 0;
acpi_scan_lock_acquire();
acpi_bus_get_device(handle, &device);
if (acpi_device_enumerated(device))
goto end;
/*
* Now add the notified device. This creates the acpi_device
* and invokes .add function
*/
result = acpi_bus_scan(handle);
if (result) {
pr_warn(PREFIX "ACPI namespace scan failed\n");
result = -EINVAL;
goto out;
}
device = NULL;
acpi_bus_get_device(handle, &device);
if (!acpi_device_enumerated(device)) {
pr_warn(PREFIX "Missing device object\n");
result = -EINVAL;
goto out;
}
end:
*mem_device = acpi_driver_data(device);
if (!(*mem_device)) {
pr_err(PREFIX "driver data not found\n");
result = -ENODEV;
goto out;
}
out:
acpi_scan_lock_release();
return result;
}
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"));
acpi_scan_lock_acquire();
if (acpi_bus_get_device(handle, &device)) {
acpi_scan_lock_release();
pr_err(PREFIX "Device doesn't exist\n");
break;
}
mem_device
|