Use dentry_path() to create full path to inode object

[pohmelfs.git] / drivers / acpi / acpica / nsxfname.c

/******************************************************************************
 *
 * Module Name: nsxfname - Public interfaces to the ACPI subsystem
 *                         ACPI Namespace oriented interfaces
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2012, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <linux/export.h>
#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "acparser.h"
#include "amlcode.h"

#define _COMPONENT          ACPI_NAMESPACE
ACPI_MODULE_NAME("nsxfname")

/* Local prototypes */
static char *acpi_ns_copy_device_id(struct acpica_device_id *dest,
                                    struct acpica_device_id *source,
                                    char *string_area);

/******************************************************************************
 *
 * FUNCTION:    acpi_get_handle
 *
 * PARAMETERS:  Parent          - Object to search under (search scope).
 *              Pathname        - Pointer to an asciiz string containing the
 *                                name
 *              ret_handle      - Where the return handle is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This routine will search for a caller specified name in the
 *              name space.  The caller can restrict the search region by
 *              specifying a non NULL parent.  The parent value is itself a
 *              namespace handle.
 *
 ******************************************************************************/

acpi_status
acpi_get_handle(acpi_handle parent,
                acpi_string pathname, acpi_handle * ret_handle)
{
        acpi_status status;
        struct acpi_namespace_node *node = NULL;
        struct acpi_namespace_node *prefix_node = NULL;

        ACPI_FUNCTION_ENTRY();

        /* Parameter Validation */

        if (!ret_handle || !pathname) {
                return (AE_BAD_PARAMETER);
        }

        /* Convert a parent handle to a prefix node */

        if (parent) {
                prefix_node = acpi_ns_validate_handle(parent);
                if (!prefix_node) {
                        return (AE_BAD_PARAMETER);
                }
        }

        /*
         * Valid cases are:
         * 1) Fully qualified pathname
         * 2) Parent + Relative pathname
         *
         * Error for <null Parent + relative path>
         */
        if (acpi_ns_valid_root_prefix(pathname[0])) {

                /* Pathname is fully qualified (starts with '\') */

                /* Special case for root-only, since we can't search for it */

                if (!ACPI_STRCMP(pathname, ACPI_NS_ROOT_PATH)) {
                        *ret_handle =
                            ACPI_CAST_PTR(acpi_handle, acpi_gbl_root_node);
                        return (AE_OK);
                }
        } else if (!prefix_node) {

                /* Relative path with null prefix is disallowed */

                return (AE_BAD_PARAMETER);
        }

        /* Find the Node and convert to a handle */

        status =
            acpi_ns_get_node(prefix_node, pathname, ACPI_NS_NO_UPSEARCH, &node);
        if (ACPI_SUCCESS(status)) {
                *ret_handle = ACPI_CAST_PTR(acpi_handle, node);
        }

        return (status);
}

ACPI_EXPORT_SYMBOL(acpi_get_handle)

/******************************************************************************
 *
 * FUNCTION:    acpi_get_name
 *
 * PARAMETERS:  Handle          - Handle to be converted to a pathname
 *              name_type       - Full pathname or single segment
 *              Buffer          - Buffer for returned path
 *
 * RETURN:      Pointer to a string containing the fully qualified Name.
 *
 * DESCRIPTION: This routine returns the fully qualified name associated with
 *              the Handle parameter.  This and the acpi_pathname_to_handle are
 *              complementary functions.
 *
 ******************************************************************************/
acpi_status
acpi_get_name(acpi_handle handle, u32 name_type, struct acpi_buffer * buffer)
{
        acpi_status status;
        struct acpi_namespace_node *node;

        /* Parameter validation */

        if (name_type > ACPI_NAME_TYPE_MAX) {
                return (AE_BAD_PARAMETER);
        }

        status = acpi_ut_validate_buffer(buffer);
        if (ACPI_FAILURE(status)) {
                return (status);
        }

        if (name_type == ACPI_FULL_PATHNAME) {

                /* Get the full pathname (From the namespace root) */

                status = acpi_ns_handle_to_pathname(handle, buffer);
                return (status);
        }

        /*
         * Wants the single segment ACPI name.
         * Validate handle and convert to a namespace Node
         */
        status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
        if (ACPI_FAILURE(status)) {
                return (status);
        }

        node = acpi_ns_validate_handle(handle);
        if (!node) {
                status = AE_BAD_PARAMETER;
                goto unlock_and_exit;
        }

        /* Validate/Allocate/Clear caller buffer */

        status = acpi_ut_initialize_buffer(buffer, ACPI_PATH_SEGMENT_LENGTH);
        if (ACPI_FAILURE(status)) {
                goto unlock_and_exit;
        }

        /* Just copy the ACPI name from the Node and zero terminate it */

        ACPI_STRNCPY(buffer->pointer, acpi_ut_get_node_name(node),
                     ACPI_NAME_SIZE);
        ((char *)buffer->pointer)[ACPI_NAME_SIZE] = 0;
        status = AE_OK;

      unlock_and_exit:

        (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
        return (status);
}

ACPI_EXPORT_SYMBOL(acpi_get_name)

/******************************************************************************
 *
 * FUNCTION:    acpi_ns_copy_device_id
 *
 * PARAMETERS:  Dest                - Pointer to the destination DEVICE_ID
 *              Source              - Pointer to the source DEVICE_ID
 *              string_area         - Pointer to where to copy the dest string
 *
 * RETURN:      Pointer to the next string area
 *
 * DESCRIPTION: Copy a single DEVICE_ID, including the string data.
 *
 ******************************************************************************/
static char *acpi_ns_copy_device_id(struct acpica_device_id *dest,
                                    struct acpica_device_id *source,
                                    char *string_area)
{
        /* Create the destination DEVICE_ID */

        dest->string = string_area;
        dest->length = source->length;

        /* Copy actual string and return a pointer to the next string area */

        ACPI_MEMCPY(string_area, source->string, source->length);
        return (string_area + source->length);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_get_object_info
 *
 * PARAMETERS:  Handle              - Object Handle
 *              return_buffer       - Where the info is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Returns information about an object as gleaned from the
 *              namespace node and possibly by running several standard
 *              control methods (Such as in the case of a device.)
 *
 * For Device and Processor objects, run the Device _HID, _UID, _CID, _STA,
 * _ADR, _sx_w, and _sx_d methods.
 *
 * Note: Allocates the return buffer, must be freed by the caller.
 *
 ******************************************************************************/

acpi_status
acpi_get_object_info(acpi_handle handle,
                     struct acpi_device_info **return_buffer)
{
        struct acpi_namespace_node *node;
        struct acpi_device_info *info;
        struct acpica_device_id_list *cid_list = NULL;
        struct acpica_device_id *hid = NULL;
        struct acpica_device_id *uid = NULL;
        char *next_id_string;
        acpi_object_type type;
        acpi_name name;
        u8 param_count = 0;
        u8 valid = 0;
        u32 info_size;
        u32 i;
        acpi_status status;

        /* Parameter validation */

        if (!handle || !return_buffer) {
                return (AE_BAD_PARAMETER);
        }

        status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
        if (ACPI_FAILURE(status)) {
                goto cleanup;
        }

        node = acpi_ns_validate_handle(handle);
        if (!node) {
                (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
                return (AE_BAD_PARAMETER);
        }

        /* Get the namespace node data while the namespace is locked */

        info_size = sizeof(struct acpi_device_info);
        type = node->type;
        name = node->name.integer;

        if (node->type == ACPI_TYPE_METHOD) {
                param_count = node->object->method.param_count;
        }

        status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
        if (ACPI_FAILURE(status)) {
                return (status);
        }

        if ((type == ACPI_TYPE_DEVICE) || (type == ACPI_TYPE_PROCESSOR)) {
                /*
                 * Get extra info for ACPI Device/Processor objects only:
                 * Run the Device _HID, _UID, and _CID methods.
                 *
                 * Note: none of these methods are required, so they may or may
                 * not be present for this device. The Info->Valid bitfield is used
                 * to indicate which methods were found and run successfully.
                 */

                /* Execute the Device._HID method */

                status = acpi_ut_execute_HID(node, &hid);
                if (ACPI_SUCCESS(status)) {
                        info_size += hid->length;
                        valid |= ACPI_VALID_HID;
                }

                /* Execute the Device._UID method */

                status = acpi_ut_execute_UID(node, &uid);
                if (ACPI_SUCCESS(status)) {
                        info_size += uid->length;
                        valid |= ACPI_VALID_UID;
                }

                /* Execute the Device._CID method */

                status = acpi_ut_execute_CID(node, &cid_list);
                if (ACPI_SUCCESS(status)) {

                        /* Add size of CID strings and CID pointer array */

                        info_size +=
                            (cid_list->list_size -
                             sizeof(struct acpica_device_id_list));
                        valid |= ACPI_VALID_CID;
                }
        }

        /*
         * Now that we have the variable-length data, we can allocate the
         * return buffer
         */
        info = ACPI_ALLOCATE_ZEROED(info_size);
        if (!info) {
                status = AE_NO_MEMORY;
                goto cleanup;
        }

        /* Get the fixed-length data */

        if ((type == ACPI_TYPE_DEVICE) || (type == ACPI_TYPE_PROCESSOR)) {
                /*
                 * Get extra info for ACPI Device/Processor objects only:
                 * Run the _STA, _ADR and, sx_w, and _sx_d methods.
                 *
                 * Note: none of these methods are required, so they may or may
                 * not be present for this device. The Info->Valid bitfield is used
                 * to indicate which methods were found and run successfully.
                 */

                /* Execute the Device._STA method */

                status = acpi_ut_execute_STA(node, &info->current_status);
                if (ACPI_SUCCESS(status)) {
                        valid |= ACPI_VALID_STA;
                }

                /* Execute the Device._ADR method */

                status = acpi_ut_evaluate_numeric_object(METHOD_NAME__ADR, node,
                                                         &info->address);
                if (ACPI_SUCCESS(status)) {
                        valid |= ACPI_VALID_ADR;
                }

                /* Execute the Device._sx_w methods */

                status = acpi_ut_execute_power_methods(node,
                                                       acpi_gbl_lowest_dstate_names,
                                                       ACPI_NUM_sx_w_METHODS,
                                                       info->lowest_dstates);
                if (ACPI_SUCCESS(status)) {
                        valid |= ACPI_VALID_SXWS;
                }

                /* Execute the Device._sx_d methods */

                status = acpi_ut_execute_power_methods(node,
                                                       acpi_gbl_highest_dstate_names,
                                                       ACPI_NUM_sx_d_METHODS,
                                                       info->highest_dstates);
                if (ACPI_SUCCESS(status)) {
                        valid |= ACPI_VALID_SXDS;
                }
        }

        /*
         * Create a pointer to the string area of the return buffer.
         * Point to the end of the base struct acpi_device_info structure.
         */
        next_id_string = ACPI_CAST_PTR(char, info->compatible_id_list.ids);
        if (cid_list) {

                /* Point past the CID DEVICE_ID array */

                next_id_string +=
                    ((acpi_size) cid_list->count *
                     sizeof(struct acpica_device_id));
        }

        /*
         * Copy the HID, UID, and CIDs to the return buffer. The variable-length
         * strings are copied to the reserved area at the end of the buffer.
         *
         * For HID and CID, check if the ID is a PCI Root Bridge.
         */
        if (hid) {
                next_id_string = acpi_ns_copy_device_id(&info->hardware_id,
                                                        hid, next_id_string);

                if (acpi_ut_is_pci_root_bridge(hid->string)) {
                        info->flags |= ACPI_PCI_ROOT_BRIDGE;
                }
        }

        if (uid) {
                next_id_string = acpi_ns_copy_device_id(&info->unique_id,
                                                        uid, next_id_string);
        }

        if (cid_list) {
                info->compatible_id_list.count = cid_list->count;
                info->compatible_id_list.list_size = cid_list->list_size;

                /* Copy each CID */

                for (i = 0; i < cid_list->count; i++) {
                        next_id_string =
                            acpi_ns_copy_device_id(&info->compatible_id_list.
                                                   ids[i], &cid_list->ids[i],
                                                   next_id_string);

                        if (acpi_ut_is_pci_root_bridge(cid_list->ids[i].string)) {
                                info->flags |= ACPI_PCI_ROOT_BRIDGE;
                        }
                }
        }

        /* Copy the fixed-length data */

        info->info_size = info_size;
        info->type = type;
        info->name = name;
        info->param_count = param_count;
        info->valid = valid;

        *return_buffer = info;
        status = AE_OK;

      cleanup:
        if (hid) {
                ACPI_FREE(hid);
        }
        if (uid) {
                ACPI_FREE(uid);
        }
        if (cid_list) {
                ACPI_FREE(cid_list);
        }
        return (status);
}

ACPI_EXPORT_SYMBOL(acpi_get_object_info)

/******************************************************************************
 *
 * FUNCTION:    acpi_install_method
 *
 * PARAMETERS:  Buffer         - An ACPI table containing one control method
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Install a control method into the namespace. If the method
 *              name already exists in the namespace, it is overwritten. The
 *              input buffer must contain a valid DSDT or SSDT containing a
 *              single control method.
 *
 ******************************************************************************/
acpi_status acpi_install_method(u8 *buffer)
{
        struct acpi_table_header *table =
            ACPI_CAST_PTR(struct acpi_table_header, buffer);
        u8 *aml_buffer;
        u8 *aml_start;
        char *path;
        struct acpi_namespace_node *node;
        union acpi_operand_object *method_obj;
        struct acpi_parse_state parser_state;
        u32 aml_length;
        u16 opcode;
        u8 method_flags;
        acpi_status status;

        /* Parameter validation */

        if (!buffer) {
                return AE_BAD_PARAMETER;
        }

        /* Table must be a DSDT or SSDT */

        if (!ACPI_COMPARE_NAME(table->signature, ACPI_SIG_DSDT) &&
            !ACPI_COMPARE_NAME(table->signature, ACPI_SIG_SSDT)) {
                return AE_BAD_HEADER;
        }

        /* First AML opcode in the table must be a control method */

        parser_state.aml = buffer + sizeof(struct acpi_table_header);
        opcode = acpi_ps_peek_opcode(&parser_state);
        if (opcode != AML_METHOD_OP) {
                return AE_BAD_PARAMETER;
        }

        /* Extract method information from the raw AML */

        parser_state.aml += acpi_ps_get_opcode_size(opcode);
        parser_state.pkg_end = acpi_ps_get_next_package_end(&parser_state);
        path = acpi_ps_get_next_namestring(&parser_state);
        method_flags = *parser_state.aml++;
        aml_start = parser_state.aml;
        aml_length = ACPI_PTR_DIFF(parser_state.pkg_end, aml_start);

        /*
         * Allocate resources up-front. We don't want to have to delete a new
         * node from the namespace if we cannot allocate memory.
         */
        aml_buffer = ACPI_ALLOCATE(aml_length);
        if (!aml_buffer) {
                return AE_NO_MEMORY;
        }

        method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD);
        if (!method_obj) {
                ACPI_FREE(aml_buffer);
                return AE_NO_MEMORY;
        }

        /* Lock namespace for acpi_ns_lookup, we may be creating a new node */

        status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
        if (ACPI_FAILURE(status)) {
                goto error_exit;
        }

        /* The lookup either returns an existing node or creates a new one */

        status =
            acpi_ns_lookup(NULL, path, ACPI_TYPE_METHOD, ACPI_IMODE_LOAD_PASS1,
                           ACPI_NS_DONT_OPEN_SCOPE | ACPI_NS_ERROR_IF_FOUND,
                           NULL, &node);

        (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);

        if (ACPI_FAILURE(status)) {     /* ns_lookup */
                if (status != AE_ALREADY_EXISTS) {
                        goto error_exit;
                }

                /* Node existed previously, make sure it is a method node */

                if (node->type != ACPI_TYPE_METHOD) {
                        status = AE_TYPE;
                        goto error_exit;
                }
        }

        /* Copy the method AML to the local buffer */

        ACPI_MEMCPY(aml_buffer, aml_start, aml_length);

        /* Initialize the method object with the new method's information */

        method_obj->method.aml_start = aml_buffer;
        method_obj->method.aml_length = aml_length;

        method_obj->method.param_count = (u8)
            (method_flags & AML_METHOD_ARG_COUNT);

        if (method_flags & AML_METHOD_SERIALIZED) {
                method_obj->method.info_flags = ACPI_METHOD_SERIALIZED;

                method_obj->method.sync_level = (u8)
                    ((method_flags & AML_METHOD_SYNC_LEVEL) >> 4);
        }

        /*
         * Now that it is complete, we can attach the new method object to
         * the method Node (detaches/deletes any existing object)
         */
        status = acpi_ns_attach_object(node, method_obj, ACPI_TYPE_METHOD);

        /*
         * Flag indicates AML buffer is dynamic, must be deleted later.
         * Must be set only after attach above.
         */
        node->flags |= ANOBJ_ALLOCATED_BUFFER;

        /* Remove local reference to the method object */

        acpi_ut_remove_reference(method_obj);
        return status;

error_exit:

        ACPI_FREE(aml_buffer);
        ACPI_FREE(method_obj);
        return status;
}
ACPI_EXPORT_SYMBOL(acpi_install_method)