linux/drivers/acpi/acpica/evrgnini.c
Rafael J. Wysocki b8fcd0e588 ACPICA: Preserve memory opregion mappings
The ACPICA's strategy with respect to the handling of memory mappings
associated with memory operation regions is to avoid mapping the
entire region at once which may be problematic at least in principle
(for example, it may lead to conflicts with overlapping mappings
having different attributes created by drivers).  It may also be
wasteful, because memory opregions on some systems take up vast
chunks of address space while the fields in those regions actually
accessed by AML are sparsely distributed.

For this reason, a one-page "window" is mapped for a given opregion
on the first memory access through it and if that "window" does not
cover an address range accessed through that opregion subsequently,
it is unmapped and a new "window" is mapped to replace it.  Next,
if the new "window" is not sufficient to acess memory through the
opregion in question in the future, it will be replaced with yet
another "window" and so on.  That may lead to a suboptimal sequence
of memory mapping and unmapping operations, for example if two fields
in one opregion separated from each other by a sufficiently wide
chunk of unused address space are accessed in an alternating pattern.

The situation may still be suboptimal if the deferred unmapping
introduced previously is supported by the OS layer.  For instance,
the alternating memory access pattern mentioned above may produce
a relatively long list of mappings to release with substantial
duplication among the entries in it, which could be avoided if
acpi_ex_system_memory_space_handler() did not release the mapping
used by it previously as soon as the current access was not covered
by it.

In order to improve that, modify acpi_ex_system_memory_space_handler()
to preserve all of the memory mappings created by it until the memory
regions associated with them go away.

Accordingly, update acpi_ev_system_memory_region_setup() to unmap all
memory associated with memory opregions that go away.

Reported-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Xiang Li <xiang.z.li@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-07-27 12:29:02 +02:00

570 lines
16 KiB
C

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: evrgnini- ACPI address_space (op_region) init
*
* Copyright (C) 2000 - 2020, Intel Corp.
*
*****************************************************************************/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acevents.h"
#include "acnamesp.h"
#include "acinterp.h"
#define _COMPONENT ACPI_EVENTS
ACPI_MODULE_NAME("evrgnini")
/*******************************************************************************
*
* FUNCTION: acpi_ev_system_memory_region_setup
*
* PARAMETERS: handle - Region we are interested in
* function - Start or stop
* handler_context - Address space handler context
* region_context - Region specific context
*
* RETURN: Status
*
* DESCRIPTION: Setup a system_memory operation region
*
******************************************************************************/
acpi_status
acpi_ev_system_memory_region_setup(acpi_handle handle,
u32 function,
void *handler_context, void **region_context)
{
union acpi_operand_object *region_desc =
(union acpi_operand_object *)handle;
struct acpi_mem_space_context *local_region_context;
struct acpi_mem_mapping *mm;
ACPI_FUNCTION_TRACE(ev_system_memory_region_setup);
if (function == ACPI_REGION_DEACTIVATE) {
if (*region_context) {
local_region_context =
(struct acpi_mem_space_context *)*region_context;
/* Delete memory mappings if present */
while (local_region_context->first_mm) {
mm = local_region_context->first_mm;
local_region_context->first_mm = mm->next_mm;
acpi_os_unmap_memory(mm->logical_address,
mm->length);
ACPI_FREE(mm);
}
ACPI_FREE(local_region_context);
*region_context = NULL;
}
return_ACPI_STATUS(AE_OK);
}
/* Create a new context */
local_region_context =
ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_mem_space_context));
if (!(local_region_context)) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/* Save the region length and address for use in the handler */
local_region_context->length = region_desc->region.length;
local_region_context->address = region_desc->region.address;
*region_context = local_region_context;
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_io_space_region_setup
*
* PARAMETERS: handle - Region we are interested in
* function - Start or stop
* handler_context - Address space handler context
* region_context - Region specific context
*
* RETURN: Status
*
* DESCRIPTION: Setup a IO operation region
*
******************************************************************************/
acpi_status
acpi_ev_io_space_region_setup(acpi_handle handle,
u32 function,
void *handler_context, void **region_context)
{
ACPI_FUNCTION_TRACE(ev_io_space_region_setup);
if (function == ACPI_REGION_DEACTIVATE) {
*region_context = NULL;
} else {
*region_context = handler_context;
}
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_pci_config_region_setup
*
* PARAMETERS: handle - Region we are interested in
* function - Start or stop
* handler_context - Address space handler context
* region_context - Region specific context
*
* RETURN: Status
*
* DESCRIPTION: Setup a PCI_Config operation region
*
* MUTEX: Assumes namespace is not locked
*
******************************************************************************/
acpi_status
acpi_ev_pci_config_region_setup(acpi_handle handle,
u32 function,
void *handler_context, void **region_context)
{
acpi_status status = AE_OK;
u64 pci_value;
struct acpi_pci_id *pci_id = *region_context;
union acpi_operand_object *handler_obj;
struct acpi_namespace_node *parent_node;
struct acpi_namespace_node *pci_root_node;
struct acpi_namespace_node *pci_device_node;
union acpi_operand_object *region_obj =
(union acpi_operand_object *)handle;
ACPI_FUNCTION_TRACE(ev_pci_config_region_setup);
handler_obj = region_obj->region.handler;
if (!handler_obj) {
/*
* No installed handler. This shouldn't happen because the dispatch
* routine checks before we get here, but we check again just in case.
*/
ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
"Attempting to init a region %p, with no handler\n",
region_obj));
return_ACPI_STATUS(AE_NOT_EXIST);
}
*region_context = NULL;
if (function == ACPI_REGION_DEACTIVATE) {
if (pci_id) {
ACPI_FREE(pci_id);
}
return_ACPI_STATUS(status);
}
parent_node = region_obj->region.node->parent;
/*
* Get the _SEG and _BBN values from the device upon which the handler
* is installed.
*
* We need to get the _SEG and _BBN objects relative to the PCI BUS device.
* This is the device the handler has been registered to handle.
*/
/*
* If the address_space.Node is still pointing to the root, we need
* to scan upward for a PCI Root bridge and re-associate the op_region
* handlers with that device.
*/
if (handler_obj->address_space.node == acpi_gbl_root_node) {
/* Start search from the parent object */
pci_root_node = parent_node;
while (pci_root_node != acpi_gbl_root_node) {
/* Get the _HID/_CID in order to detect a root_bridge */
if (acpi_ev_is_pci_root_bridge(pci_root_node)) {
/* Install a handler for this PCI root bridge */
status = acpi_install_address_space_handler((acpi_handle)pci_root_node, ACPI_ADR_SPACE_PCI_CONFIG, ACPI_DEFAULT_HANDLER, NULL, NULL);
if (ACPI_FAILURE(status)) {
if (status == AE_SAME_HANDLER) {
/*
* It is OK if the handler is already installed on the
* root bridge. Still need to return a context object
* for the new PCI_Config operation region, however.
*/
} else {
ACPI_EXCEPTION((AE_INFO, status,
"Could not install PciConfig handler "
"for Root Bridge %4.4s",
acpi_ut_get_node_name
(pci_root_node)));
}
}
break;
}
pci_root_node = pci_root_node->parent;
}
/* PCI root bridge not found, use namespace root node */
} else {
pci_root_node = handler_obj->address_space.node;
}
/*
* If this region is now initialized, we are done.
* (install_address_space_handler could have initialized it)
*/
if (region_obj->region.flags & AOPOBJ_SETUP_COMPLETE) {
return_ACPI_STATUS(AE_OK);
}
/* Region is still not initialized. Create a new context */
pci_id = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_pci_id));
if (!pci_id) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
/*
* For PCI_Config space access, we need the segment, bus, device and
* function numbers. Acquire them here.
*
* Find the parent device object. (This allows the operation region to be
* within a subscope under the device, such as a control method.)
*/
pci_device_node = region_obj->region.node;
while (pci_device_node && (pci_device_node->type != ACPI_TYPE_DEVICE)) {
pci_device_node = pci_device_node->parent;
}
if (!pci_device_node) {
ACPI_FREE(pci_id);
return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
}
/*
* Get the PCI device and function numbers from the _ADR object
* contained in the parent's scope.
*/
status = acpi_ut_evaluate_numeric_object(METHOD_NAME__ADR,
pci_device_node, &pci_value);
/*
* The default is zero, and since the allocation above zeroed the data,
* just do nothing on failure.
*/
if (ACPI_SUCCESS(status)) {
pci_id->device = ACPI_HIWORD(ACPI_LODWORD(pci_value));
pci_id->function = ACPI_LOWORD(ACPI_LODWORD(pci_value));
}
/* The PCI segment number comes from the _SEG method */
status = acpi_ut_evaluate_numeric_object(METHOD_NAME__SEG,
pci_root_node, &pci_value);
if (ACPI_SUCCESS(status)) {
pci_id->segment = ACPI_LOWORD(pci_value);
}
/* The PCI bus number comes from the _BBN method */
status = acpi_ut_evaluate_numeric_object(METHOD_NAME__BBN,
pci_root_node, &pci_value);
if (ACPI_SUCCESS(status)) {
pci_id->bus = ACPI_LOWORD(pci_value);
}
/* Complete/update the PCI ID for this device */
status =
acpi_hw_derive_pci_id(pci_id, pci_root_node,
region_obj->region.node);
if (ACPI_FAILURE(status)) {
ACPI_FREE(pci_id);
return_ACPI_STATUS(status);
}
*region_context = pci_id;
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_is_pci_root_bridge
*
* PARAMETERS: node - Device node being examined
*
* RETURN: TRUE if device is a PCI/PCI-Express Root Bridge
*
* DESCRIPTION: Determine if the input device represents a PCI Root Bridge by
* examining the _HID and _CID for the device.
*
******************************************************************************/
u8 acpi_ev_is_pci_root_bridge(struct acpi_namespace_node *node)
{
acpi_status status;
struct acpi_pnp_device_id *hid;
struct acpi_pnp_device_id_list *cid;
u32 i;
u8 match;
/* Get the _HID and check for a PCI Root Bridge */
status = acpi_ut_execute_HID(node, &hid);
if (ACPI_FAILURE(status)) {
return (FALSE);
}
match = acpi_ut_is_pci_root_bridge(hid->string);
ACPI_FREE(hid);
if (match) {
return (TRUE);
}
/* The _HID did not match. Get the _CID and check for a PCI Root Bridge */
status = acpi_ut_execute_CID(node, &cid);
if (ACPI_FAILURE(status)) {
return (FALSE);
}
/* Check all _CIDs in the returned list */
for (i = 0; i < cid->count; i++) {
if (acpi_ut_is_pci_root_bridge(cid->ids[i].string)) {
ACPI_FREE(cid);
return (TRUE);
}
}
ACPI_FREE(cid);
return (FALSE);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_pci_bar_region_setup
*
* PARAMETERS: handle - Region we are interested in
* function - Start or stop
* handler_context - Address space handler context
* region_context - Region specific context
*
* RETURN: Status
*
* DESCRIPTION: Setup a pci_BAR operation region
*
* MUTEX: Assumes namespace is not locked
*
******************************************************************************/
acpi_status
acpi_ev_pci_bar_region_setup(acpi_handle handle,
u32 function,
void *handler_context, void **region_context)
{
ACPI_FUNCTION_TRACE(ev_pci_bar_region_setup);
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_cmos_region_setup
*
* PARAMETERS: handle - Region we are interested in
* function - Start or stop
* handler_context - Address space handler context
* region_context - Region specific context
*
* RETURN: Status
*
* DESCRIPTION: Setup a CMOS operation region
*
* MUTEX: Assumes namespace is not locked
*
******************************************************************************/
acpi_status
acpi_ev_cmos_region_setup(acpi_handle handle,
u32 function,
void *handler_context, void **region_context)
{
ACPI_FUNCTION_TRACE(ev_cmos_region_setup);
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_default_region_setup
*
* PARAMETERS: handle - Region we are interested in
* function - Start or stop
* handler_context - Address space handler context
* region_context - Region specific context
*
* RETURN: Status
*
* DESCRIPTION: Default region initialization
*
******************************************************************************/
acpi_status
acpi_ev_default_region_setup(acpi_handle handle,
u32 function,
void *handler_context, void **region_context)
{
ACPI_FUNCTION_TRACE(ev_default_region_setup);
if (function == ACPI_REGION_DEACTIVATE) {
*region_context = NULL;
} else {
*region_context = handler_context;
}
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_initialize_region
*
* PARAMETERS: region_obj - Region we are initializing
*
* RETURN: Status
*
* DESCRIPTION: Initializes the region, finds any _REG methods and saves them
* for execution at a later time
*
* Get the appropriate address space handler for a newly
* created region.
*
* This also performs address space specific initialization. For
* example, PCI regions must have an _ADR object that contains
* a PCI address in the scope of the definition. This address is
* required to perform an access to PCI config space.
*
* MUTEX: Interpreter should be unlocked, because we may run the _REG
* method for this region.
*
* NOTE: Possible incompliance:
* There is a behavior conflict in automatic _REG execution:
* 1. When the interpreter is evaluating a method, we can only
* automatically run _REG for the following case:
* operation_region (OPR1, 0x80, 0x1000010, 0x4)
* 2. When the interpreter is loading a table, we can also
* automatically run _REG for the following case:
* operation_region (OPR1, 0x80, 0x1000010, 0x4)
* Though this may not be compliant to the de-facto standard, the
* logic is kept in order not to trigger regressions. And keeping
* this logic should be taken care by the caller of this function.
*
******************************************************************************/
acpi_status acpi_ev_initialize_region(union acpi_operand_object *region_obj)
{
union acpi_operand_object *handler_obj;
union acpi_operand_object *obj_desc;
acpi_adr_space_type space_id;
struct acpi_namespace_node *node;
ACPI_FUNCTION_TRACE(ev_initialize_region);
if (!region_obj) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
if (region_obj->common.flags & AOPOBJ_OBJECT_INITIALIZED) {
return_ACPI_STATUS(AE_OK);
}
region_obj->common.flags |= AOPOBJ_OBJECT_INITIALIZED;
node = region_obj->region.node->parent;
space_id = region_obj->region.space_id;
/*
* The following loop depends upon the root Node having no parent
* ie: acpi_gbl_root_node->Parent being set to NULL
*/
while (node) {
/* Check to see if a handler exists */
handler_obj = NULL;
obj_desc = acpi_ns_get_attached_object(node);
if (obj_desc) {
/* Can only be a handler if the object exists */
switch (node->type) {
case ACPI_TYPE_DEVICE:
case ACPI_TYPE_PROCESSOR:
case ACPI_TYPE_THERMAL:
handler_obj = obj_desc->common_notify.handler;
break;
default:
/* Ignore other objects */
break;
}
handler_obj =
acpi_ev_find_region_handler(space_id, handler_obj);
if (handler_obj) {
/* Found correct handler */
ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
"Found handler %p for region %p in obj %p\n",
handler_obj, region_obj,
obj_desc));
(void)acpi_ev_attach_region(handler_obj,
region_obj, FALSE);
/*
* Tell all users that this region is usable by
* running the _REG method
*/
acpi_ex_exit_interpreter();
(void)acpi_ev_execute_reg_method(region_obj,
ACPI_REG_CONNECT);
acpi_ex_enter_interpreter();
return_ACPI_STATUS(AE_OK);
}
}
/* This node does not have the handler we need; Pop up one level */
node = node->parent;
}
/*
* If we get here, there is no handler for this region. This is not
* fatal because many regions get created before a handler is installed
* for said region.
*/
ACPI_DEBUG_PRINT((ACPI_DB_OPREGION,
"No handler for RegionType %s(%X) (RegionObj %p)\n",
acpi_ut_get_region_name(space_id), space_id,
region_obj));
return_ACPI_STATUS(AE_OK);
}