mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 15:16:39 +07:00
95c9617472
Use of "unsigned int" is preferred to bare "unsigned" in net tree. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
520 lines
20 KiB
C
520 lines
20 KiB
C
/*
|
|
* Linux WiMAX
|
|
* Kernel space API for accessing WiMAX devices
|
|
*
|
|
*
|
|
* Copyright (C) 2007-2008 Intel Corporation <linux-wimax@intel.com>
|
|
* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
|
|
*
|
|
* 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.
|
|
*
|
|
* 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., 51 Franklin Street, Fifth Floor, Boston, MA
|
|
* 02110-1301, USA.
|
|
*
|
|
*
|
|
* The WiMAX stack provides an API for controlling and managing the
|
|
* system's WiMAX devices. This API affects the control plane; the
|
|
* data plane is accessed via the network stack (netdev).
|
|
*
|
|
* Parts of the WiMAX stack API and notifications are exported to
|
|
* user space via Generic Netlink. In user space, libwimax (part of
|
|
* the wimax-tools package) provides a shim layer for accessing those
|
|
* calls.
|
|
*
|
|
* The API is standarized for all WiMAX devices and different drivers
|
|
* implement the backend support for it. However, device-specific
|
|
* messaging pipes are provided that can be used to issue commands and
|
|
* receive notifications in free form.
|
|
*
|
|
* Currently the messaging pipes are the only means of control as it
|
|
* is not known (due to the lack of more devices in the market) what
|
|
* will be a good abstraction layer. Expect this to change as more
|
|
* devices show in the market. This API is designed to be growable in
|
|
* order to address this problem.
|
|
*
|
|
* USAGE
|
|
*
|
|
* Embed a `struct wimax_dev` at the beginning of the the device's
|
|
* private structure, initialize and register it. For details, see
|
|
* `struct wimax_dev`s documentation.
|
|
*
|
|
* Once this is done, wimax-tools's libwimaxll can be used to
|
|
* communicate with the driver from user space. You user space
|
|
* application does not have to forcibily use libwimaxll and can talk
|
|
* the generic netlink protocol directly if desired.
|
|
*
|
|
* Remember this is a very low level API that will to provide all of
|
|
* WiMAX features. Other daemons and services running in user space
|
|
* are the expected clients of it. They offer a higher level API that
|
|
* applications should use (an example of this is the Intel's WiMAX
|
|
* Network Service for the i2400m).
|
|
*
|
|
* DESIGN
|
|
*
|
|
* Although not set on final stone, this very basic interface is
|
|
* mostly completed. Remember this is meant to grow as new common
|
|
* operations are decided upon. New operations will be added to the
|
|
* interface, intent being on keeping backwards compatibility as much
|
|
* as possible.
|
|
*
|
|
* This layer implements a set of calls to control a WiMAX device,
|
|
* exposing a frontend to the rest of the kernel and user space (via
|
|
* generic netlink) and a backend implementation in the driver through
|
|
* function pointers.
|
|
*
|
|
* WiMAX devices have a state, and a kernel-only API allows the
|
|
* drivers to manipulate that state. State transitions are atomic, and
|
|
* only some of them are allowed (see `enum wimax_st`).
|
|
*
|
|
* Most API calls will set the state automatically; in most cases
|
|
* drivers have to only report state changes due to external
|
|
* conditions.
|
|
*
|
|
* All API operations are 'atomic', serialized through a mutex in the
|
|
* `struct wimax_dev`.
|
|
*
|
|
* EXPORTING TO USER SPACE THROUGH GENERIC NETLINK
|
|
*
|
|
* The API is exported to user space using generic netlink (other
|
|
* methods can be added as needed).
|
|
*
|
|
* There is a Generic Netlink Family named "WiMAX", where interfaces
|
|
* supporting the WiMAX interface receive commands and broadcast their
|
|
* signals over a multicast group named "msg".
|
|
*
|
|
* Mapping to the source/destination interface is done by an interface
|
|
* index attribute.
|
|
*
|
|
* For user-to-kernel traffic (commands) we use a function call
|
|
* marshalling mechanism, where a message X with attributes A, B, C
|
|
* sent from user space to kernel space means executing the WiMAX API
|
|
* call wimax_X(A, B, C), sending the results back as a message.
|
|
*
|
|
* Kernel-to-user (notifications or signals) communication is sent
|
|
* over multicast groups. This allows to have multiple applications
|
|
* monitoring them.
|
|
*
|
|
* Each command/signal gets assigned it's own attribute policy. This
|
|
* way the validator will verify that all the attributes in there are
|
|
* only the ones that should be for each command/signal. Thing of an
|
|
* attribute mapping to a type+argumentname for each command/signal.
|
|
*
|
|
* If we had a single policy for *all* commands/signals, after running
|
|
* the validator we'd have to check "does this attribute belong in
|
|
* here"? for each one. It can be done manually, but it's just easier
|
|
* to have the validator do that job with multiple policies. As well,
|
|
* it makes it easier to later expand each command/signal signature
|
|
* without affecting others and keeping the namespace more or less
|
|
* sane. Not that it is too complicated, but it makes it even easier.
|
|
*
|
|
* No state information is maintained in the kernel for each user
|
|
* space connection (the connection is stateless).
|
|
*
|
|
* TESTING FOR THE INTERFACE AND VERSIONING
|
|
*
|
|
* If network interface X is a WiMAX device, there will be a Generic
|
|
* Netlink family named "WiMAX X" and the device will present a
|
|
* "wimax" directory in it's network sysfs directory
|
|
* (/sys/class/net/DEVICE/wimax) [used by HAL].
|
|
*
|
|
* The inexistence of any of these means the device does not support
|
|
* this WiMAX API.
|
|
*
|
|
* By querying the generic netlink controller, versioning information
|
|
* and the multicast groups available can be found. Applications using
|
|
* the interface can either rely on that or use the generic netlink
|
|
* controller to figure out which generic netlink commands/signals are
|
|
* supported.
|
|
*
|
|
* NOTE: this versioning is a last resort to avoid hard
|
|
* incompatibilities. It is the intention of the design of this
|
|
* stack not to introduce backward incompatible changes.
|
|
*
|
|
* The version code has to fit in one byte (restrictions imposed by
|
|
* generic netlink); we use `version / 10` for the major version and
|
|
* `version % 10` for the minor. This gives 9 minors for each major
|
|
* and 25 majors.
|
|
*
|
|
* The version change protocol is as follow:
|
|
*
|
|
* - Major versions: needs to be increased if an existing message/API
|
|
* call is changed or removed. Doesn't need to be changed if a new
|
|
* message is added.
|
|
*
|
|
* - Minor version: needs to be increased if new messages/API calls are
|
|
* being added or some other consideration that doesn't impact the
|
|
* user-kernel interface too much (like some kind of bug fix) and
|
|
* that is kind of left up in the air to common sense.
|
|
*
|
|
* User space code should not try to work if the major version it was
|
|
* compiled for differs from what the kernel offers. As well, if the
|
|
* minor version of the kernel interface is lower than the one user
|
|
* space is expecting (the one it was compiled for), the kernel
|
|
* might be missing API calls; user space shall be ready to handle
|
|
* said condition. Use the generic netlink controller operations to
|
|
* find which ones are supported and which not.
|
|
*
|
|
* libwimaxll:wimaxll_open() takes care of checking versions.
|
|
*
|
|
* THE OPERATIONS:
|
|
*
|
|
* Each operation is defined in its on file (drivers/net/wimax/op-*.c)
|
|
* for clarity. The parts needed for an operation are:
|
|
*
|
|
* - a function pointer in `struct wimax_dev`: optional, as the
|
|
* operation might be implemented by the stack and not by the
|
|
* driver.
|
|
*
|
|
* All function pointers are named wimax_dev->op_*(), and drivers
|
|
* must implement them except where noted otherwise.
|
|
*
|
|
* - When exported to user space, a `struct nla_policy` to define the
|
|
* attributes of the generic netlink command and a `struct genl_ops`
|
|
* to define the operation.
|
|
*
|
|
* All the declarations for the operation codes (WIMAX_GNL_OP_<NAME>)
|
|
* and generic netlink attributes (WIMAX_GNL_<NAME>_*) are declared in
|
|
* include/linux/wimax.h; this file is intended to be cloned by user
|
|
* space to gain access to those declarations.
|
|
*
|
|
* A few caveats to remember:
|
|
*
|
|
* - Need to define attribute numbers starting in 1; otherwise it
|
|
* fails.
|
|
*
|
|
* - the `struct genl_family` requires a maximum attribute id; when
|
|
* defining the `struct nla_policy` for each message, it has to have
|
|
* an array size of WIMAX_GNL_ATTR_MAX+1.
|
|
*
|
|
* The op_*() function pointers will not be called if the wimax_dev is
|
|
* in a state <= %WIMAX_ST_UNINITIALIZED. The exception is:
|
|
*
|
|
* - op_reset: can be called at any time after wimax_dev_add() has
|
|
* been called.
|
|
*
|
|
* THE PIPE INTERFACE:
|
|
*
|
|
* This interface is kept intentionally simple. The driver can send
|
|
* and receive free-form messages to/from user space through a
|
|
* pipe. See drivers/net/wimax/op-msg.c for details.
|
|
*
|
|
* The kernel-to-user messages are sent with
|
|
* wimax_msg(). user-to-kernel messages are delivered via
|
|
* wimax_dev->op_msg_from_user().
|
|
*
|
|
* RFKILL:
|
|
*
|
|
* RFKILL support is built into the wimax_dev layer; the driver just
|
|
* needs to call wimax_report_rfkill_{hw,sw}() to inform of changes in
|
|
* the hardware or software RF kill switches. When the stack wants to
|
|
* turn the radio off, it will call wimax_dev->op_rfkill_sw_toggle(),
|
|
* which the driver implements.
|
|
*
|
|
* User space can set the software RF Kill switch by calling
|
|
* wimax_rfkill().
|
|
*
|
|
* The code for now only supports devices that don't require polling;
|
|
* If the device needs to be polled, create a self-rearming delayed
|
|
* work struct for polling or look into adding polled support to the
|
|
* WiMAX stack.
|
|
*
|
|
* When initializing the hardware (_probe), after calling
|
|
* wimax_dev_add(), query the device for it's RF Kill switches status
|
|
* and feed it back to the WiMAX stack using
|
|
* wimax_report_rfkill_{hw,sw}(). If any switch is missing, always
|
|
* report it as ON.
|
|
*
|
|
* NOTE: the wimax stack uses an inverted terminology to that of the
|
|
* RFKILL subsystem:
|
|
*
|
|
* - ON: radio is ON, RFKILL is DISABLED or OFF.
|
|
* - OFF: radio is OFF, RFKILL is ENABLED or ON.
|
|
*
|
|
* MISCELLANEOUS OPS:
|
|
*
|
|
* wimax_reset() can be used to reset the device to power on state; by
|
|
* default it issues a warm reset that maintains the same device
|
|
* node. If that is not possible, it falls back to a cold reset
|
|
* (device reconnect). The driver implements the backend to this
|
|
* through wimax_dev->op_reset().
|
|
*/
|
|
|
|
#ifndef __NET__WIMAX_H__
|
|
#define __NET__WIMAX_H__
|
|
|
|
#include <linux/wimax.h>
|
|
#include <net/genetlink.h>
|
|
#include <linux/netdevice.h>
|
|
|
|
struct net_device;
|
|
struct genl_info;
|
|
struct wimax_dev;
|
|
|
|
/**
|
|
* struct wimax_dev - Generic WiMAX device
|
|
*
|
|
* @net_dev: [fill] Pointer to the &struct net_device this WiMAX
|
|
* device implements.
|
|
*
|
|
* @op_msg_from_user: [fill] Driver-specific operation to
|
|
* handle a raw message from user space to the driver. The
|
|
* driver can send messages to user space using with
|
|
* wimax_msg_to_user().
|
|
*
|
|
* @op_rfkill_sw_toggle: [fill] Driver-specific operation to act on
|
|
* userspace (or any other agent) requesting the WiMAX device to
|
|
* change the RF Kill software switch (WIMAX_RF_ON or
|
|
* WIMAX_RF_OFF).
|
|
* If such hardware support is not present, it is assumed the
|
|
* radio cannot be switched off and it is always on (and the stack
|
|
* will error out when trying to switch it off). In such case,
|
|
* this function pointer can be left as NULL.
|
|
*
|
|
* @op_reset: [fill] Driver specific operation to reset the
|
|
* device.
|
|
* This operation should always attempt first a warm reset that
|
|
* does not disconnect the device from the bus and return 0.
|
|
* If that fails, it should resort to some sort of cold or bus
|
|
* reset (even if it implies a bus disconnection and device
|
|
* disappearance). In that case, -ENODEV should be returned to
|
|
* indicate the device is gone.
|
|
* This operation has to be synchronous, and return only when the
|
|
* reset is complete. In case of having had to resort to bus/cold
|
|
* reset implying a device disconnection, the call is allowed to
|
|
* return inmediately.
|
|
* NOTE: wimax_dev->mutex is NOT locked when this op is being
|
|
* called; however, wimax_dev->mutex_reset IS locked to ensure
|
|
* serialization of calls to wimax_reset().
|
|
* See wimax_reset()'s documentation.
|
|
*
|
|
* @name: [fill] A way to identify this device. We need to register a
|
|
* name with many subsystems (rfkill, workqueue creation, etc).
|
|
* We can't use the network device name as that
|
|
* might change and in some instances we don't know it yet (until
|
|
* we don't call register_netdev()). So we generate an unique one
|
|
* using the driver name and device bus id, place it here and use
|
|
* it across the board. Recommended naming:
|
|
* DRIVERNAME-BUSNAME:BUSID (dev->bus->name, dev->bus_id).
|
|
*
|
|
* @id_table_node: [private] link to the list of wimax devices kept by
|
|
* id-table.c. Protected by it's own spinlock.
|
|
*
|
|
* @mutex: [private] Serializes all concurrent access and execution of
|
|
* operations.
|
|
*
|
|
* @mutex_reset: [private] Serializes reset operations. Needs to be a
|
|
* different mutex because as part of the reset operation, the
|
|
* driver has to call back into the stack to do things such as
|
|
* state change, that require wimax_dev->mutex.
|
|
*
|
|
* @state: [private] Current state of the WiMAX device.
|
|
*
|
|
* @rfkill: [private] integration into the RF-Kill infrastructure.
|
|
*
|
|
* @rf_sw: [private] State of the software radio switch (OFF/ON)
|
|
*
|
|
* @rf_hw: [private] State of the hardware radio switch (OFF/ON)
|
|
*
|
|
* @debugfs_dentry: [private] Used to hook up a debugfs entry. This
|
|
* shows up in the debugfs root as wimax\:DEVICENAME.
|
|
*
|
|
* Description:
|
|
* This structure defines a common interface to access all WiMAX
|
|
* devices from different vendors and provides a common API as well as
|
|
* a free-form device-specific messaging channel.
|
|
*
|
|
* Usage:
|
|
* 1. Embed a &struct wimax_dev at *the beginning* the network
|
|
* device structure so that netdev_priv() points to it.
|
|
*
|
|
* 2. memset() it to zero
|
|
*
|
|
* 3. Initialize with wimax_dev_init(). This will leave the WiMAX
|
|
* device in the %__WIMAX_ST_NULL state.
|
|
*
|
|
* 4. Fill all the fields marked with [fill]; once called
|
|
* wimax_dev_add(), those fields CANNOT be modified.
|
|
*
|
|
* 5. Call wimax_dev_add() *after* registering the network
|
|
* device. This will leave the WiMAX device in the %WIMAX_ST_DOWN
|
|
* state.
|
|
* Protect the driver's net_device->open() against succeeding if
|
|
* the wimax device state is lower than %WIMAX_ST_DOWN.
|
|
*
|
|
* 6. Select when the device is going to be turned on/initialized;
|
|
* for example, it could be initialized on 'ifconfig up' (when the
|
|
* netdev op 'open()' is called on the driver).
|
|
*
|
|
* When the device is initialized (at `ifconfig up` time, or right
|
|
* after calling wimax_dev_add() from _probe(), make sure the
|
|
* following steps are taken
|
|
*
|
|
* a. Move the device to %WIMAX_ST_UNINITIALIZED. This is needed so
|
|
* some API calls that shouldn't work until the device is ready
|
|
* can be blocked.
|
|
*
|
|
* b. Initialize the device. Make sure to turn the SW radio switch
|
|
* off and move the device to state %WIMAX_ST_RADIO_OFF when
|
|
* done. When just initialized, a device should be left in RADIO
|
|
* OFF state until user space devices to turn it on.
|
|
*
|
|
* c. Query the device for the state of the hardware rfkill switch
|
|
* and call wimax_rfkill_report_hw() and wimax_rfkill_report_sw()
|
|
* as needed. See below.
|
|
*
|
|
* wimax_dev_rm() undoes before unregistering the network device. Once
|
|
* wimax_dev_add() is called, the driver can get called on the
|
|
* wimax_dev->op_* function pointers
|
|
*
|
|
* CONCURRENCY:
|
|
*
|
|
* The stack provides a mutex for each device that will disallow API
|
|
* calls happening concurrently; thus, op calls into the driver
|
|
* through the wimax_dev->op*() function pointers will always be
|
|
* serialized and *never* concurrent.
|
|
*
|
|
* For locking, take wimax_dev->mutex is taken; (most) operations in
|
|
* the API have to check for wimax_dev_is_ready() to return 0 before
|
|
* continuing (this is done internally).
|
|
*
|
|
* REFERENCE COUNTING:
|
|
*
|
|
* The WiMAX device is reference counted by the associated network
|
|
* device. The only operation that can be used to reference the device
|
|
* is wimax_dev_get_by_genl_info(), and the reference it acquires has
|
|
* to be released with dev_put(wimax_dev->net_dev).
|
|
*
|
|
* RFKILL:
|
|
*
|
|
* At startup, both HW and SW radio switchess are assumed to be off.
|
|
*
|
|
* At initialization time [after calling wimax_dev_add()], have the
|
|
* driver query the device for the status of the software and hardware
|
|
* RF kill switches and call wimax_report_rfkill_hw() and
|
|
* wimax_rfkill_report_sw() to indicate their state. If any is
|
|
* missing, just call it to indicate it is ON (radio always on).
|
|
*
|
|
* Whenever the driver detects a change in the state of the RF kill
|
|
* switches, it should call wimax_report_rfkill_hw() or
|
|
* wimax_report_rfkill_sw() to report it to the stack.
|
|
*/
|
|
struct wimax_dev {
|
|
struct net_device *net_dev;
|
|
struct list_head id_table_node;
|
|
struct mutex mutex; /* Protects all members and API calls */
|
|
struct mutex mutex_reset;
|
|
enum wimax_st state;
|
|
|
|
int (*op_msg_from_user)(struct wimax_dev *wimax_dev,
|
|
const char *,
|
|
const void *, size_t,
|
|
const struct genl_info *info);
|
|
int (*op_rfkill_sw_toggle)(struct wimax_dev *wimax_dev,
|
|
enum wimax_rf_state);
|
|
int (*op_reset)(struct wimax_dev *wimax_dev);
|
|
|
|
struct rfkill *rfkill;
|
|
unsigned int rf_hw;
|
|
unsigned int rf_sw;
|
|
char name[32];
|
|
|
|
struct dentry *debugfs_dentry;
|
|
};
|
|
|
|
|
|
|
|
/*
|
|
* WiMAX stack public API for device drivers
|
|
* -----------------------------------------
|
|
*
|
|
* These functions are not exported to user space.
|
|
*/
|
|
extern void wimax_dev_init(struct wimax_dev *);
|
|
extern int wimax_dev_add(struct wimax_dev *, struct net_device *);
|
|
extern void wimax_dev_rm(struct wimax_dev *);
|
|
|
|
static inline
|
|
struct wimax_dev *net_dev_to_wimax(struct net_device *net_dev)
|
|
{
|
|
return netdev_priv(net_dev);
|
|
}
|
|
|
|
static inline
|
|
struct device *wimax_dev_to_dev(struct wimax_dev *wimax_dev)
|
|
{
|
|
return wimax_dev->net_dev->dev.parent;
|
|
}
|
|
|
|
extern void wimax_state_change(struct wimax_dev *, enum wimax_st);
|
|
extern enum wimax_st wimax_state_get(struct wimax_dev *);
|
|
|
|
/*
|
|
* Radio Switch state reporting.
|
|
*
|
|
* enum wimax_rf_state is declared in linux/wimax.h so the exports
|
|
* to user space can use it.
|
|
*/
|
|
extern void wimax_report_rfkill_hw(struct wimax_dev *, enum wimax_rf_state);
|
|
extern void wimax_report_rfkill_sw(struct wimax_dev *, enum wimax_rf_state);
|
|
|
|
|
|
/*
|
|
* Free-form messaging to/from user space
|
|
*
|
|
* Sending a message:
|
|
*
|
|
* wimax_msg(wimax_dev, pipe_name, buf, buf_size, GFP_KERNEL);
|
|
*
|
|
* Broken up:
|
|
*
|
|
* skb = wimax_msg_alloc(wimax_dev, pipe_name, buf_size, GFP_KERNEL);
|
|
* ...fill up skb...
|
|
* wimax_msg_send(wimax_dev, pipe_name, skb);
|
|
*
|
|
* Be sure not to modify skb->data in the middle (ie: don't use
|
|
* skb_push()/skb_pull()/skb_reserve() on the skb).
|
|
*
|
|
* "pipe_name" is any string, than can be interpreted as the name of
|
|
* the pipe or destinatary; the interpretation of it is driver
|
|
* specific, so the recipient can multiplex it as wished. It can be
|
|
* NULL, it won't be used - an example is using a "diagnostics" tag to
|
|
* send diagnostics information that a device-specific diagnostics
|
|
* tool would be interested in.
|
|
*/
|
|
extern struct sk_buff *wimax_msg_alloc(struct wimax_dev *, const char *,
|
|
const void *, size_t, gfp_t);
|
|
extern int wimax_msg_send(struct wimax_dev *, struct sk_buff *);
|
|
extern int wimax_msg(struct wimax_dev *, const char *,
|
|
const void *, size_t, gfp_t);
|
|
|
|
extern const void *wimax_msg_data_len(struct sk_buff *, size_t *);
|
|
extern const void *wimax_msg_data(struct sk_buff *);
|
|
extern ssize_t wimax_msg_len(struct sk_buff *);
|
|
|
|
|
|
/*
|
|
* WiMAX stack user space API
|
|
* --------------------------
|
|
*
|
|
* This API is what gets exported to user space for general
|
|
* operations. As well, they can be called from within the kernel,
|
|
* (with a properly referenced `struct wimax_dev`).
|
|
*
|
|
* Properly referenced means: the 'struct net_device' that embeds the
|
|
* device's control structure and (as such) the 'struct wimax_dev' is
|
|
* referenced by the caller.
|
|
*/
|
|
extern int wimax_rfkill(struct wimax_dev *, enum wimax_rf_state);
|
|
extern int wimax_reset(struct wimax_dev *);
|
|
|
|
#endif /* #ifndef __NET__WIMAX_H__ */
|