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linux/drivers/acpi/utils.c
Pavel Machek 40599072dc ACPI: scheduling in atomic via acpi_evaluate_integer () 
Now I know why I had strange "scheduling in atomic" problems:
acpi_evaluate_integer() does malloc(..., irqs_disabled() ? GFP_ATOMIC
: GFP_KERNEL)... which is (of course) broken.

There's no way to reliably tell if we need GFP_ATOMIC or not from
code, this one for example fails to detect spinlocks held.

Fortunately, allocation seems small enough to be done on stack.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-11-26 17:39:06 -05:00

427 lines
10 KiB
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/*
* acpi_utils.c - ACPI Utility Functions ($Revision: 10 $)
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@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. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#define _COMPONENT ACPI_BUS_COMPONENT
ACPI_MODULE_NAME("utils");
/* --------------------------------------------------------------------------
Object Evaluation Helpers
-------------------------------------------------------------------------- */
static void
acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
{
#ifdef ACPI_DEBUG_OUTPUT
char prefix[80] = {'\0'};
struct acpi_buffer buffer = {sizeof(prefix), prefix};
acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
(char *) prefix, p, acpi_format_exception(s)));
#else
return;
#endif
}
acpi_status
acpi_extract_package(union acpi_object *package,
struct acpi_buffer *format, struct acpi_buffer *buffer)
{
u32 size_required = 0;
u32 tail_offset = 0;
char *format_string = NULL;
u32 format_count = 0;
u32 i = 0;
u8 *head = NULL;
u8 *tail = NULL;
if (!package || (package->type != ACPI_TYPE_PACKAGE)
|| (package->package.count < 1)) {
printk(KERN_WARNING PREFIX "Invalid package argument\n");
return AE_BAD_PARAMETER;
}
if (!format || !format->pointer || (format->length < 1)) {
printk(KERN_WARNING PREFIX "Invalid format argument\n");
return AE_BAD_PARAMETER;
}
if (!buffer) {
printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
return AE_BAD_PARAMETER;
}
format_count = (format->length / sizeof(char)) - 1;
if (format_count > package->package.count) {
printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
" than exist in package [%d].\n",
format_count, package->package.count);
return AE_BAD_DATA;
}
format_string = format->pointer;
/*
* Calculate size_required.
*/
for (i = 0; i < format_count; i++) {
union acpi_object *element = &(package->package.elements[i]);
if (!element) {
return AE_BAD_DATA;
}
switch (element->type) {
case ACPI_TYPE_INTEGER:
switch (format_string[i]) {
case 'N':
size_required += sizeof(acpi_integer);
tail_offset += sizeof(acpi_integer);
break;
case 'S':
size_required +=
sizeof(char *) + sizeof(acpi_integer) +
sizeof(char);
tail_offset += sizeof(char *);
break;
default:
printk(KERN_WARNING PREFIX "Invalid package element"
" [%d]: got number, expecing"
" [%c]\n",
i, format_string[i]);
return AE_BAD_DATA;
break;
}
break;
case ACPI_TYPE_STRING:
case ACPI_TYPE_BUFFER:
switch (format_string[i]) {
case 'S':
size_required +=
sizeof(char *) +
(element->string.length * sizeof(char)) +
sizeof(char);
tail_offset += sizeof(char *);
break;
case 'B':
size_required +=
sizeof(u8 *) +
(element->buffer.length * sizeof(u8));
tail_offset += sizeof(u8 *);
break;
default:
printk(KERN_WARNING PREFIX "Invalid package element"
" [%d] got string/buffer,"
" expecing [%c]\n",
i, format_string[i]);
return AE_BAD_DATA;
break;
}
break;
case ACPI_TYPE_PACKAGE:
default:
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Found unsupported element at index=%d\n",
i));
/* TBD: handle nested packages... */
return AE_SUPPORT;
break;
}
}
/*
* Validate output buffer.
*/
if (buffer->length < size_required) {
buffer->length = size_required;
return AE_BUFFER_OVERFLOW;
} else if (buffer->length != size_required || !buffer->pointer) {
return AE_BAD_PARAMETER;
}
head = buffer->pointer;
tail = buffer->pointer + tail_offset;
/*
* Extract package data.
*/
for (i = 0; i < format_count; i++) {
u8 **pointer = NULL;
union acpi_object *element = &(package->package.elements[i]);
if (!element) {
return AE_BAD_DATA;
}
switch (element->type) {
case ACPI_TYPE_INTEGER:
switch (format_string[i]) {
case 'N':
*((acpi_integer *) head) =
element->integer.value;
head += sizeof(acpi_integer);
break;
case 'S':
pointer = (u8 **) head;
*pointer = tail;
*((acpi_integer *) tail) =
element->integer.value;
head += sizeof(acpi_integer *);
tail += sizeof(acpi_integer);
/* NULL terminate string */
*tail = (char)0;
tail += sizeof(char);
break;
default:
/* Should never get here */
break;
}
break;
case ACPI_TYPE_STRING:
case ACPI_TYPE_BUFFER:
switch (format_string[i]) {
case 'S':
pointer = (u8 **) head;
*pointer = tail;
memcpy(tail, element->string.pointer,
element->string.length);
head += sizeof(char *);
tail += element->string.length * sizeof(char);
/* NULL terminate string */
*tail = (char)0;
tail += sizeof(char);
break;
case 'B':
pointer = (u8 **) head;
*pointer = tail;
memcpy(tail, element->buffer.pointer,
element->buffer.length);
head += sizeof(u8 *);
tail += element->buffer.length * sizeof(u8);
break;
default:
/* Should never get here */
break;
}
break;
case ACPI_TYPE_PACKAGE:
/* TBD: handle nested packages... */
default:
/* Should never get here */
break;
}
}
return AE_OK;
}
EXPORT_SYMBOL(acpi_extract_package);
acpi_status
acpi_evaluate_integer(acpi_handle handle,
acpi_string pathname,
struct acpi_object_list *arguments, unsigned long long *data)
{
acpi_status status = AE_OK;
union acpi_object element;
struct acpi_buffer buffer = { 0, NULL };
if (!data)
return AE_BAD_PARAMETER;
buffer.length = sizeof(union acpi_object);
buffer.pointer = &element;
status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
if (ACPI_FAILURE(status)) {
acpi_util_eval_error(handle, pathname, status);
return status;
}
if (element.type != ACPI_TYPE_INTEGER) {
acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
return AE_BAD_DATA;
}
*data = element.integer.value;
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
return AE_OK;
}
EXPORT_SYMBOL(acpi_evaluate_integer);
#if 0
acpi_status
acpi_evaluate_string(acpi_handle handle,
acpi_string pathname,
acpi_object_list * arguments, acpi_string * data)
{
acpi_status status = AE_OK;
acpi_object *element = NULL;
acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
if (!data)
return AE_BAD_PARAMETER;
status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
if (ACPI_FAILURE(status)) {
acpi_util_eval_error(handle, pathname, status);
return status;
}
element = (acpi_object *) buffer.pointer;
if ((element->type != ACPI_TYPE_STRING)
|| (element->type != ACPI_TYPE_BUFFER)
|| !element->string.length) {
acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
return AE_BAD_DATA;
}
*data = kzalloc(element->string.length + 1, GFP_KERNEL);
if (!data) {
printk(KERN_ERR PREFIX "Memory allocation\n");
return -ENOMEM;
}
memcpy(*data, element->string.pointer, element->string.length);
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%s]\n", *data));
kfree(buffer.pointer);
return AE_OK;
}
#endif
acpi_status
acpi_evaluate_reference(acpi_handle handle,
acpi_string pathname,
struct acpi_object_list *arguments,
struct acpi_handle_list *list)
{
acpi_status status = AE_OK;
union acpi_object *package = NULL;
union acpi_object *element = NULL;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
u32 i = 0;
if (!list) {
return AE_BAD_PARAMETER;
}
/* Evaluate object. */
status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
if (ACPI_FAILURE(status))
goto end;
package = buffer.pointer;
if ((buffer.length == 0) || !package) {
printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n",
(unsigned)buffer.length, package);
status = AE_BAD_DATA;
acpi_util_eval_error(handle, pathname, status);
goto end;
}
if (package->type != ACPI_TYPE_PACKAGE) {
printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n",
package->type);
status = AE_BAD_DATA;
acpi_util_eval_error(handle, pathname, status);
goto end;
}
if (!package->package.count) {
printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n",
package);
status = AE_BAD_DATA;
acpi_util_eval_error(handle, pathname, status);
goto end;
}
if (package->package.count > ACPI_MAX_HANDLES) {
return AE_NO_MEMORY;
}
list->count = package->package.count;
/* Extract package data. */
for (i = 0; i < list->count; i++) {
element = &(package->package.elements[i]);
if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
status = AE_BAD_DATA;
printk(KERN_ERR PREFIX
"Expecting a [Reference] package element, found type %X\n",
element->type);
acpi_util_eval_error(handle, pathname, status);
break;
}
if (!element->reference.handle) {
printk(KERN_WARNING PREFIX "Invalid reference in"
" package %s\n", pathname);
status = AE_NULL_ENTRY;
break;
}
/* Get the acpi_handle. */
list->handles[i] = element->reference.handle;
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
list->handles[i]));
}
end:
if (ACPI_FAILURE(status)) {
list->count = 0;
//kfree(list->handles);
}
kfree(buffer.pointer);
return status;
}
EXPORT_SYMBOL(acpi_evaluate_reference);
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