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alistair23-linux/include/uapi/linux/wmi.h

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platform/x86: wmi: create userspace interface for drivers For WMI operations that are only Set or Query readable and writable sysfs attributes created by WMI vendor drivers or the bus driver makes sense. For other WMI operations that are run on Method, there needs to be a way to guarantee to userspace that the results from the method call belong to the data request to the method call. Sysfs attributes don't work well in this scenario because two userspace processes may be competing at reading/writing an attribute and step on each other's data. When a WMI vendor driver declares a callback method in the wmi_driver the WMI bus driver will create a character device that maps to that function. This callback method will be responsible for filtering invalid requests and performing the actual call. That character device will correspond to this path: /dev/wmi/$driver Performing read() on this character device will provide the size of the buffer that the character device needs to perform calls. This buffer size can be set by vendor drivers through a new symbol or when MOF parsing is available by the MOF. Performing ioctl() on this character device will be interpretd by the WMI bus driver. It will perform sanity tests for size of data, test them for a valid instance, copy the data from userspace and pass iton to the vendor driver to further process and run. This creates an implicit policy that each driver will only be allowed a single character device. If a module matches multiple GUID's, the wmi_devices will need to be all handled by the same wmi_driver. The WMI vendor drivers will be responsible for managing inappropriate access to this character device and proper locking on data used by it. When a WMI vendor driver is unloaded the WMI bus driver will clean up the character device and any memory allocated for the call. Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> Reviewed-by: Edward O'Callaghan <quasisec@google.com> Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
2017-11-01 13:25:35 -06:00
/*
* User API methods for ACPI-WMI mapping driver
*
* Copyright (C) 2017 Dell, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _UAPI_LINUX_WMI_H
#define _UAPI_LINUX_WMI_H
platform/x86: dell-smbios-wmi: introduce userspace interface It's important for the driver to provide a R/W ioctl to ensure that two competing userspace processes don't race to provide or read each others data. This userspace character device will be used to perform SMBIOS calls from any applications. It provides an ioctl that will allow passing the WMI calling interface buffer between userspace and kernel space. This character device is intended to deprecate the dcdbas kernel module and the interface that it provides to userspace. To perform an SMBIOS IOCTL call using the character device userspace will perform a read() on the the character device. The WMI bus will provide a u64 variable containing the necessary size of the IOCTL buffer. The API for interacting with this interface is defined in documentation as well as the WMI uapi header provides the format of the structures. Not all userspace requests will be accepted. The dell-smbios filtering functionality will be used to prevent access to certain tokens and calls. All whitelisted commands and tokens are now shared out to userspace so applications don't need to define them in their own headers. Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> Reviewed-by: Edward O'Callaghan <quasisec@google.com> Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
2017-11-01 13:25:36 -06:00
#include <linux/ioctl.h>
platform/x86: wmi: create userspace interface for drivers For WMI operations that are only Set or Query readable and writable sysfs attributes created by WMI vendor drivers or the bus driver makes sense. For other WMI operations that are run on Method, there needs to be a way to guarantee to userspace that the results from the method call belong to the data request to the method call. Sysfs attributes don't work well in this scenario because two userspace processes may be competing at reading/writing an attribute and step on each other's data. When a WMI vendor driver declares a callback method in the wmi_driver the WMI bus driver will create a character device that maps to that function. This callback method will be responsible for filtering invalid requests and performing the actual call. That character device will correspond to this path: /dev/wmi/$driver Performing read() on this character device will provide the size of the buffer that the character device needs to perform calls. This buffer size can be set by vendor drivers through a new symbol or when MOF parsing is available by the MOF. Performing ioctl() on this character device will be interpretd by the WMI bus driver. It will perform sanity tests for size of data, test them for a valid instance, copy the data from userspace and pass iton to the vendor driver to further process and run. This creates an implicit policy that each driver will only be allowed a single character device. If a module matches multiple GUID's, the wmi_devices will need to be all handled by the same wmi_driver. The WMI vendor drivers will be responsible for managing inappropriate access to this character device and proper locking on data used by it. When a WMI vendor driver is unloaded the WMI bus driver will clean up the character device and any memory allocated for the call. Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> Reviewed-by: Edward O'Callaghan <quasisec@google.com> Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
2017-11-01 13:25:35 -06:00
#include <linux/types.h>
/* WMI bus will filter all WMI vendor driver requests through this IOC */
#define WMI_IOC 'W'
/* All ioctl requests through WMI should declare their size followed by
* relevant data objects
*/
struct wmi_ioctl_buffer {
__u64 length;
__u8 data[];
};
platform/x86: dell-smbios-wmi: introduce userspace interface It's important for the driver to provide a R/W ioctl to ensure that two competing userspace processes don't race to provide or read each others data. This userspace character device will be used to perform SMBIOS calls from any applications. It provides an ioctl that will allow passing the WMI calling interface buffer between userspace and kernel space. This character device is intended to deprecate the dcdbas kernel module and the interface that it provides to userspace. To perform an SMBIOS IOCTL call using the character device userspace will perform a read() on the the character device. The WMI bus will provide a u64 variable containing the necessary size of the IOCTL buffer. The API for interacting with this interface is defined in documentation as well as the WMI uapi header provides the format of the structures. Not all userspace requests will be accepted. The dell-smbios filtering functionality will be used to prevent access to certain tokens and calls. All whitelisted commands and tokens are now shared out to userspace so applications don't need to define them in their own headers. Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> Reviewed-by: Edward O'Callaghan <quasisec@google.com> Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
2017-11-01 13:25:36 -06:00
/* This structure may be modified by the firmware when we enter
* system management mode through SMM, hence the volatiles
*/
struct calling_interface_buffer {
__u16 cmd_class;
__u16 cmd_select;
volatile __u32 input[4];
volatile __u32 output[4];
} __packed;
struct dell_wmi_extensions {
__u32 argattrib;
__u32 blength;
__u8 data[];
} __packed;
struct dell_wmi_smbios_buffer {
__u64 length;
struct calling_interface_buffer std;
struct dell_wmi_extensions ext;
} __packed;
/* Whitelisted smbios class/select commands */
#define CLASS_TOKEN_READ 0
#define CLASS_TOKEN_WRITE 1
#define SELECT_TOKEN_STD 0
#define SELECT_TOKEN_BAT 1
#define SELECT_TOKEN_AC 2
#define CLASS_FLASH_INTERFACE 7
#define SELECT_FLASH_INTERFACE 3
#define CLASS_ADMIN_PROP 10
#define SELECT_ADMIN_PROP 3
#define CLASS_INFO 17
#define SELECT_RFKILL 11
#define SELECT_APP_REGISTRATION 3
#define SELECT_DOCK 22
/* whitelisted tokens */
#define CAPSULE_EN_TOKEN 0x0461
#define CAPSULE_DIS_TOKEN 0x0462
#define WSMT_EN_TOKEN 0x04EC
#define WSMT_DIS_TOKEN 0x04ED
/* Dell SMBIOS calling IOCTL command used by dell-smbios-wmi */
#define DELL_WMI_SMBIOS_CMD _IOWR(WMI_IOC, 0, struct dell_wmi_smbios_buffer)
platform/x86: wmi: create userspace interface for drivers For WMI operations that are only Set or Query readable and writable sysfs attributes created by WMI vendor drivers or the bus driver makes sense. For other WMI operations that are run on Method, there needs to be a way to guarantee to userspace that the results from the method call belong to the data request to the method call. Sysfs attributes don't work well in this scenario because two userspace processes may be competing at reading/writing an attribute and step on each other's data. When a WMI vendor driver declares a callback method in the wmi_driver the WMI bus driver will create a character device that maps to that function. This callback method will be responsible for filtering invalid requests and performing the actual call. That character device will correspond to this path: /dev/wmi/$driver Performing read() on this character device will provide the size of the buffer that the character device needs to perform calls. This buffer size can be set by vendor drivers through a new symbol or when MOF parsing is available by the MOF. Performing ioctl() on this character device will be interpretd by the WMI bus driver. It will perform sanity tests for size of data, test them for a valid instance, copy the data from userspace and pass iton to the vendor driver to further process and run. This creates an implicit policy that each driver will only be allowed a single character device. If a module matches multiple GUID's, the wmi_devices will need to be all handled by the same wmi_driver. The WMI vendor drivers will be responsible for managing inappropriate access to this character device and proper locking on data used by it. When a WMI vendor driver is unloaded the WMI bus driver will clean up the character device and any memory allocated for the call. Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> Reviewed-by: Edward O'Callaghan <quasisec@google.com> Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
2017-11-01 13:25:35 -06:00
#endif
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