ubuntu-linux-kernel/drivers/misc/mei/client.c

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2024-04-01 15:06:58 +00:00
/*
*
* Intel Management Engine Interface (Intel MEI) Linux driver
* Copyright (c) 2003-2012, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
*/
#include <linux/sched/signal.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/mei.h>
#include "mei_dev.h"
#include "hbm.h"
#include "client.h"
/**
* mei_me_cl_init - initialize me client
*
* @me_cl: me client
*/
void mei_me_cl_init(struct mei_me_client *me_cl)
{
INIT_LIST_HEAD(&me_cl->list);
kref_init(&me_cl->refcnt);
}
/**
* mei_me_cl_get - increases me client refcount
*
* @me_cl: me client
*
* Locking: called under "dev->device_lock" lock
*
* Return: me client or NULL
*/
struct mei_me_client *mei_me_cl_get(struct mei_me_client *me_cl)
{
if (me_cl && kref_get_unless_zero(&me_cl->refcnt))
return me_cl;
return NULL;
}
/**
* mei_me_cl_release - free me client
*
* Locking: called under "dev->device_lock" lock
*
* @ref: me_client refcount
*/
static void mei_me_cl_release(struct kref *ref)
{
struct mei_me_client *me_cl =
container_of(ref, struct mei_me_client, refcnt);
kfree(me_cl);
}
/**
* mei_me_cl_put - decrease me client refcount and free client if necessary
*
* Locking: called under "dev->device_lock" lock
*
* @me_cl: me client
*/
void mei_me_cl_put(struct mei_me_client *me_cl)
{
if (me_cl)
kref_put(&me_cl->refcnt, mei_me_cl_release);
}
/**
* __mei_me_cl_del - delete me client from the list and decrease
* reference counter
*
* @dev: mei device
* @me_cl: me client
*
* Locking: dev->me_clients_rwsem
*/
static void __mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
{
if (!me_cl)
return;
list_del_init(&me_cl->list);
mei_me_cl_put(me_cl);
}
/**
* mei_me_cl_del - delete me client from the list and decrease
* reference counter
*
* @dev: mei device
* @me_cl: me client
*/
void mei_me_cl_del(struct mei_device *dev, struct mei_me_client *me_cl)
{
down_write(&dev->me_clients_rwsem);
__mei_me_cl_del(dev, me_cl);
up_write(&dev->me_clients_rwsem);
}
/**
* mei_me_cl_add - add me client to the list
*
* @dev: mei device
* @me_cl: me client
*/
void mei_me_cl_add(struct mei_device *dev, struct mei_me_client *me_cl)
{
down_write(&dev->me_clients_rwsem);
list_add(&me_cl->list, &dev->me_clients);
up_write(&dev->me_clients_rwsem);
}
/**
* __mei_me_cl_by_uuid - locate me client by uuid
* increases ref count
*
* @dev: mei device
* @uuid: me client uuid
*
* Return: me client or NULL if not found
*
* Locking: dev->me_clients_rwsem
*/
static struct mei_me_client *__mei_me_cl_by_uuid(struct mei_device *dev,
const uuid_le *uuid)
{
struct mei_me_client *me_cl;
const uuid_le *pn;
WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
list_for_each_entry(me_cl, &dev->me_clients, list) {
pn = &me_cl->props.protocol_name;
if (uuid_le_cmp(*uuid, *pn) == 0)
return mei_me_cl_get(me_cl);
}
return NULL;
}
/**
* mei_me_cl_by_uuid - locate me client by uuid
* increases ref count
*
* @dev: mei device
* @uuid: me client uuid
*
* Return: me client or NULL if not found
*
* Locking: dev->me_clients_rwsem
*/
struct mei_me_client *mei_me_cl_by_uuid(struct mei_device *dev,
const uuid_le *uuid)
{
struct mei_me_client *me_cl;
down_read(&dev->me_clients_rwsem);
me_cl = __mei_me_cl_by_uuid(dev, uuid);
up_read(&dev->me_clients_rwsem);
return me_cl;
}
/**
* mei_me_cl_by_id - locate me client by client id
* increases ref count
*
* @dev: the device structure
* @client_id: me client id
*
* Return: me client or NULL if not found
*
* Locking: dev->me_clients_rwsem
*/
struct mei_me_client *mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
{
struct mei_me_client *__me_cl, *me_cl = NULL;
down_read(&dev->me_clients_rwsem);
list_for_each_entry(__me_cl, &dev->me_clients, list) {
if (__me_cl->client_id == client_id) {
me_cl = mei_me_cl_get(__me_cl);
break;
}
}
up_read(&dev->me_clients_rwsem);
return me_cl;
}
/**
* __mei_me_cl_by_uuid_id - locate me client by client id and uuid
* increases ref count
*
* @dev: the device structure
* @uuid: me client uuid
* @client_id: me client id
*
* Return: me client or null if not found
*
* Locking: dev->me_clients_rwsem
*/
static struct mei_me_client *__mei_me_cl_by_uuid_id(struct mei_device *dev,
const uuid_le *uuid, u8 client_id)
{
struct mei_me_client *me_cl;
const uuid_le *pn;
WARN_ON(!rwsem_is_locked(&dev->me_clients_rwsem));
list_for_each_entry(me_cl, &dev->me_clients, list) {
pn = &me_cl->props.protocol_name;
if (uuid_le_cmp(*uuid, *pn) == 0 &&
me_cl->client_id == client_id)
return mei_me_cl_get(me_cl);
}
return NULL;
}
/**
* mei_me_cl_by_uuid_id - locate me client by client id and uuid
* increases ref count
*
* @dev: the device structure
* @uuid: me client uuid
* @client_id: me client id
*
* Return: me client or null if not found
*/
struct mei_me_client *mei_me_cl_by_uuid_id(struct mei_device *dev,
const uuid_le *uuid, u8 client_id)
{
struct mei_me_client *me_cl;
down_read(&dev->me_clients_rwsem);
me_cl = __mei_me_cl_by_uuid_id(dev, uuid, client_id);
up_read(&dev->me_clients_rwsem);
return me_cl;
}
/**
* mei_me_cl_rm_by_uuid - remove all me clients matching uuid
*
* @dev: the device structure
* @uuid: me client uuid
*
* Locking: called under "dev->device_lock" lock
*/
void mei_me_cl_rm_by_uuid(struct mei_device *dev, const uuid_le *uuid)
{
struct mei_me_client *me_cl;
dev_dbg(dev->dev, "remove %pUl\n", uuid);
down_write(&dev->me_clients_rwsem);
me_cl = __mei_me_cl_by_uuid(dev, uuid);
__mei_me_cl_del(dev, me_cl);
up_write(&dev->me_clients_rwsem);
}
/**
* mei_me_cl_rm_by_uuid_id - remove all me clients matching client id
*
* @dev: the device structure
* @uuid: me client uuid
* @id: me client id
*
* Locking: called under "dev->device_lock" lock
*/
void mei_me_cl_rm_by_uuid_id(struct mei_device *dev, const uuid_le *uuid, u8 id)
{
struct mei_me_client *me_cl;
dev_dbg(dev->dev, "remove %pUl %d\n", uuid, id);
down_write(&dev->me_clients_rwsem);
me_cl = __mei_me_cl_by_uuid_id(dev, uuid, id);
__mei_me_cl_del(dev, me_cl);
up_write(&dev->me_clients_rwsem);
}
/**
* mei_me_cl_rm_all - remove all me clients
*
* @dev: the device structure
*
* Locking: called under "dev->device_lock" lock
*/
void mei_me_cl_rm_all(struct mei_device *dev)
{
struct mei_me_client *me_cl, *next;
down_write(&dev->me_clients_rwsem);
list_for_each_entry_safe(me_cl, next, &dev->me_clients, list)
__mei_me_cl_del(dev, me_cl);
up_write(&dev->me_clients_rwsem);
}
/**
* mei_cl_cmp_id - tells if the clients are the same
*
* @cl1: host client 1
* @cl2: host client 2
*
* Return: true - if the clients has same host and me ids
* false - otherwise
*/
static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
const struct mei_cl *cl2)
{
return cl1 && cl2 &&
(cl1->host_client_id == cl2->host_client_id) &&
(mei_cl_me_id(cl1) == mei_cl_me_id(cl2));
}
/**
* mei_io_cb_free - free mei_cb_private related memory
*
* @cb: mei callback struct
*/
void mei_io_cb_free(struct mei_cl_cb *cb)
{
if (cb == NULL)
return;
list_del(&cb->list);
kfree(cb->buf.data);
kfree(cb);
}
/**
* mei_io_cb_init - allocate and initialize io callback
*
* @cl: mei client
* @type: operation type
* @fp: pointer to file structure
*
* Return: mei_cl_cb pointer or NULL;
*/
static struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl,
enum mei_cb_file_ops type,
const struct file *fp)
{
struct mei_cl_cb *cb;
cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
if (!cb)
return NULL;
INIT_LIST_HEAD(&cb->list);
cb->fp = fp;
cb->cl = cl;
cb->buf_idx = 0;
cb->fop_type = type;
return cb;
}
/**
* __mei_io_list_flush_cl - removes and frees cbs belonging to cl.
*
* @head: an instance of our list structure
* @cl: host client, can be NULL for flushing the whole list
* @free: whether to free the cbs
*/
static void __mei_io_list_flush_cl(struct list_head *head,
const struct mei_cl *cl, bool free)
{
struct mei_cl_cb *cb, *next;
/* enable removing everything if no cl is specified */
list_for_each_entry_safe(cb, next, head, list) {
if (!cl || mei_cl_cmp_id(cl, cb->cl)) {
list_del_init(&cb->list);
if (free)
mei_io_cb_free(cb);
}
}
}
/**
* mei_io_list_flush_cl - removes list entry belonging to cl.
*
* @head: An instance of our list structure
* @cl: host client
*/
static inline void mei_io_list_flush_cl(struct list_head *head,
const struct mei_cl *cl)
{
__mei_io_list_flush_cl(head, cl, false);
}
/**
* mei_io_list_free_cl - removes cb belonging to cl and free them
*
* @head: An instance of our list structure
* @cl: host client
*/
static inline void mei_io_list_free_cl(struct list_head *head,
const struct mei_cl *cl)
{
__mei_io_list_flush_cl(head, cl, true);
}
/**
* mei_io_list_free_fp - free cb from a list that matches file pointer
*
* @head: io list
* @fp: file pointer (matching cb file object), may be NULL
*/
static void mei_io_list_free_fp(struct list_head *head, const struct file *fp)
{
struct mei_cl_cb *cb, *next;
list_for_each_entry_safe(cb, next, head, list)
if (!fp || fp == cb->fp)
mei_io_cb_free(cb);
}
/**
* mei_cl_alloc_cb - a convenient wrapper for allocating read cb
*
* @cl: host client
* @length: size of the buffer
* @fop_type: operation type
* @fp: associated file pointer (might be NULL)
*
* Return: cb on success and NULL on failure
*/
struct mei_cl_cb *mei_cl_alloc_cb(struct mei_cl *cl, size_t length,
enum mei_cb_file_ops fop_type,
const struct file *fp)
{
struct mei_cl_cb *cb;
cb = mei_io_cb_init(cl, fop_type, fp);
if (!cb)
return NULL;
if (length == 0)
return cb;
cb->buf.data = kmalloc(length, GFP_KERNEL);
if (!cb->buf.data) {
mei_io_cb_free(cb);
return NULL;
}
cb->buf.size = length;
return cb;
}
/**
* mei_cl_enqueue_ctrl_wr_cb - a convenient wrapper for allocating
* and enqueuing of the control commands cb
*
* @cl: host client
* @length: size of the buffer
* @fop_type: operation type
* @fp: associated file pointer (might be NULL)
*
* Return: cb on success and NULL on failure
* Locking: called under "dev->device_lock" lock
*/
struct mei_cl_cb *mei_cl_enqueue_ctrl_wr_cb(struct mei_cl *cl, size_t length,
enum mei_cb_file_ops fop_type,
const struct file *fp)
{
struct mei_cl_cb *cb;
/* for RX always allocate at least client's mtu */
if (length)
length = max_t(size_t, length, mei_cl_mtu(cl));
cb = mei_cl_alloc_cb(cl, length, fop_type, fp);
if (!cb)
return NULL;
list_add_tail(&cb->list, &cl->dev->ctrl_wr_list);
return cb;
}
/**
* mei_cl_read_cb - find this cl's callback in the read list
* for a specific file
*
* @cl: host client
* @fp: file pointer (matching cb file object), may be NULL
*
* Return: cb on success, NULL if cb is not found
*/
struct mei_cl_cb *mei_cl_read_cb(const struct mei_cl *cl, const struct file *fp)
{
struct mei_cl_cb *cb;
list_for_each_entry(cb, &cl->rd_completed, list)
if (!fp || fp == cb->fp)
return cb;
return NULL;
}
/**
* mei_cl_flush_queues - flushes queue lists belonging to cl.
*
* @cl: host client
* @fp: file pointer (matching cb file object), may be NULL
*
* Return: 0 on success, -EINVAL if cl or cl->dev is NULL.
*/
int mei_cl_flush_queues(struct mei_cl *cl, const struct file *fp)
{
struct mei_device *dev;
if (WARN_ON(!cl || !cl->dev))
return -EINVAL;
dev = cl->dev;
cl_dbg(dev, cl, "remove list entry belonging to cl\n");
mei_io_list_free_cl(&cl->dev->write_list, cl);
mei_io_list_free_cl(&cl->dev->write_waiting_list, cl);
mei_io_list_flush_cl(&cl->dev->ctrl_wr_list, cl);
mei_io_list_flush_cl(&cl->dev->ctrl_rd_list, cl);
mei_io_list_free_fp(&cl->rd_pending, fp);
mei_io_list_free_fp(&cl->rd_completed, fp);
return 0;
}
/**
* mei_cl_init - initializes cl.
*
* @cl: host client to be initialized
* @dev: mei device
*/
static void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
{
memset(cl, 0, sizeof(struct mei_cl));
init_waitqueue_head(&cl->wait);
init_waitqueue_head(&cl->rx_wait);
init_waitqueue_head(&cl->tx_wait);
init_waitqueue_head(&cl->ev_wait);
INIT_LIST_HEAD(&cl->rd_completed);
INIT_LIST_HEAD(&cl->rd_pending);
INIT_LIST_HEAD(&cl->link);
cl->writing_state = MEI_IDLE;
cl->state = MEI_FILE_UNINITIALIZED;
cl->dev = dev;
}
/**
* mei_cl_allocate - allocates cl structure and sets it up.
*
* @dev: mei device
* Return: The allocated file or NULL on failure
*/
struct mei_cl *mei_cl_allocate(struct mei_device *dev)
{
struct mei_cl *cl;
cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
if (!cl)
return NULL;
mei_cl_init(cl, dev);
return cl;
}
/**
* mei_cl_link - allocate host id in the host map
*
* @cl: host client
*
* Return: 0 on success
* -EINVAL on incorrect values
* -EMFILE if open count exceeded.
*/
int mei_cl_link(struct mei_cl *cl)
{
struct mei_device *dev;
int id;
if (WARN_ON(!cl || !cl->dev))
return -EINVAL;
dev = cl->dev;
id = find_first_zero_bit(dev->host_clients_map, MEI_CLIENTS_MAX);
if (id >= MEI_CLIENTS_MAX) {
dev_err(dev->dev, "id exceeded %d", MEI_CLIENTS_MAX);
return -EMFILE;
}
if (dev->open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
dev_err(dev->dev, "open_handle_count exceeded %d",
MEI_MAX_OPEN_HANDLE_COUNT);
return -EMFILE;
}
dev->open_handle_count++;
cl->host_client_id = id;
list_add_tail(&cl->link, &dev->file_list);
set_bit(id, dev->host_clients_map);
cl->state = MEI_FILE_INITIALIZING;
cl_dbg(dev, cl, "link cl\n");
return 0;
}
/**
* mei_cl_unlink - remove host client from the list
*
* @cl: host client
*
* Return: always 0
*/
int mei_cl_unlink(struct mei_cl *cl)
{
struct mei_device *dev;
/* don't shout on error exit path */
if (!cl)
return 0;
if (WARN_ON(!cl->dev))
return 0;
dev = cl->dev;
cl_dbg(dev, cl, "unlink client");
if (dev->open_handle_count > 0)
dev->open_handle_count--;
/* never clear the 0 bit */
if (cl->host_client_id)
clear_bit(cl->host_client_id, dev->host_clients_map);
list_del_init(&cl->link);
cl->state = MEI_FILE_UNINITIALIZED;
cl->writing_state = MEI_IDLE;
WARN_ON(!list_empty(&cl->rd_completed) ||
!list_empty(&cl->rd_pending) ||
!list_empty(&cl->link));
return 0;
}
void mei_host_client_init(struct mei_device *dev)
{
dev->dev_state = MEI_DEV_ENABLED;
dev->reset_count = 0;
schedule_work(&dev->bus_rescan_work);
pm_runtime_mark_last_busy(dev->dev);
dev_dbg(dev->dev, "rpm: autosuspend\n");
pm_request_autosuspend(dev->dev);
}
/**
* mei_hbuf_acquire - try to acquire host buffer
*
* @dev: the device structure
* Return: true if host buffer was acquired
*/
bool mei_hbuf_acquire(struct mei_device *dev)
{
if (mei_pg_state(dev) == MEI_PG_ON ||
mei_pg_in_transition(dev)) {
dev_dbg(dev->dev, "device is in pg\n");
return false;
}
if (!dev->hbuf_is_ready) {
dev_dbg(dev->dev, "hbuf is not ready\n");
return false;
}
dev->hbuf_is_ready = false;
return true;
}
/**
* mei_cl_wake_all - wake up readers, writers and event waiters so
* they can be interrupted
*
* @cl: host client
*/
static void mei_cl_wake_all(struct mei_cl *cl)
{
struct mei_device *dev = cl->dev;
/* synchronized under device mutex */
if (waitqueue_active(&cl->rx_wait)) {
cl_dbg(dev, cl, "Waking up reading client!\n");
wake_up_interruptible(&cl->rx_wait);
}
/* synchronized under device mutex */
if (waitqueue_active(&cl->tx_wait)) {
cl_dbg(dev, cl, "Waking up writing client!\n");
wake_up_interruptible(&cl->tx_wait);
}
/* synchronized under device mutex */
if (waitqueue_active(&cl->ev_wait)) {
cl_dbg(dev, cl, "Waking up waiting for event clients!\n");
wake_up_interruptible(&cl->ev_wait);
}
/* synchronized under device mutex */
if (waitqueue_active(&cl->wait)) {
cl_dbg(dev, cl, "Waking up ctrl write clients!\n");
wake_up(&cl->wait);
}
}
/**
* mei_cl_set_disconnected - set disconnected state and clear
* associated states and resources
*
* @cl: host client
*/
static void mei_cl_set_disconnected(struct mei_cl *cl)
{
struct mei_device *dev = cl->dev;
if (cl->state == MEI_FILE_DISCONNECTED ||
cl->state <= MEI_FILE_INITIALIZING)
return;
cl->state = MEI_FILE_DISCONNECTED;
mei_io_list_free_cl(&dev->write_list, cl);
mei_io_list_free_cl(&dev->write_waiting_list, cl);
mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
mei_cl_wake_all(cl);
cl->rx_flow_ctrl_creds = 0;
cl->tx_flow_ctrl_creds = 0;
cl->timer_count = 0;
mei_cl_bus_module_put(cl);
if (!cl->me_cl)
return;
if (!WARN_ON(cl->me_cl->connect_count == 0))
cl->me_cl->connect_count--;
if (cl->me_cl->connect_count == 0)
cl->me_cl->tx_flow_ctrl_creds = 0;
mei_me_cl_put(cl->me_cl);
cl->me_cl = NULL;
}
static int mei_cl_set_connecting(struct mei_cl *cl, struct mei_me_client *me_cl)
{
if (!mei_me_cl_get(me_cl))
return -ENOENT;
/* only one connection is allowed for fixed address clients */
if (me_cl->props.fixed_address) {
if (me_cl->connect_count) {
mei_me_cl_put(me_cl);
return -EBUSY;
}
}
cl->me_cl = me_cl;
cl->state = MEI_FILE_CONNECTING;
cl->me_cl->connect_count++;
return 0;
}
/*
* mei_cl_send_disconnect - send disconnect request
*
* @cl: host client
* @cb: callback block
*
* Return: 0, OK; otherwise, error.
*/
static int mei_cl_send_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb)
{
struct mei_device *dev;
int ret;
dev = cl->dev;
ret = mei_hbm_cl_disconnect_req(dev, cl);
cl->status = ret;
if (ret) {
cl->state = MEI_FILE_DISCONNECT_REPLY;
return ret;
}
list_move_tail(&cb->list, &dev->ctrl_rd_list);
cl->timer_count = MEI_CONNECT_TIMEOUT;
mei_schedule_stall_timer(dev);
return 0;
}
/**
* mei_cl_irq_disconnect - processes close related operation from
* interrupt thread context - send disconnect request
*
* @cl: client
* @cb: callback block.
* @cmpl_list: complete list.
*
* Return: 0, OK; otherwise, error.
*/
int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
struct list_head *cmpl_list)
{
struct mei_device *dev = cl->dev;
u32 msg_slots;
int slots;
int ret;
msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
slots = mei_hbuf_empty_slots(dev);
if (slots < msg_slots)
return -EMSGSIZE;
ret = mei_cl_send_disconnect(cl, cb);
if (ret)
list_move_tail(&cb->list, cmpl_list);
return ret;
}
/**
* __mei_cl_disconnect - disconnect host client from the me one
* internal function runtime pm has to be already acquired
*
* @cl: host client
*
* Return: 0 on success, <0 on failure.
*/
static int __mei_cl_disconnect(struct mei_cl *cl)
{
struct mei_device *dev;
struct mei_cl_cb *cb;
int rets;
dev = cl->dev;
cl->state = MEI_FILE_DISCONNECTING;
cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT, NULL);
if (!cb) {
rets = -ENOMEM;
goto out;
}
if (mei_hbuf_acquire(dev)) {
rets = mei_cl_send_disconnect(cl, cb);
if (rets) {
cl_err(dev, cl, "failed to disconnect.\n");
goto out;
}
}
mutex_unlock(&dev->device_lock);
wait_event_timeout(cl->wait,
cl->state == MEI_FILE_DISCONNECT_REPLY ||
cl->state == MEI_FILE_DISCONNECTED,
mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
mutex_lock(&dev->device_lock);
rets = cl->status;
if (cl->state != MEI_FILE_DISCONNECT_REPLY &&
cl->state != MEI_FILE_DISCONNECTED) {
cl_dbg(dev, cl, "timeout on disconnect from FW client.\n");
rets = -ETIME;
}
out:
/* we disconnect also on error */
mei_cl_set_disconnected(cl);
if (!rets)
cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
mei_io_cb_free(cb);
return rets;
}
/**
* mei_cl_disconnect - disconnect host client from the me one
*
* @cl: host client
*
* Locking: called under "dev->device_lock" lock
*
* Return: 0 on success, <0 on failure.
*/
int mei_cl_disconnect(struct mei_cl *cl)
{
struct mei_device *dev;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
cl_dbg(dev, cl, "disconnecting");
if (!mei_cl_is_connected(cl))
return 0;
if (mei_cl_is_fixed_address(cl)) {
mei_cl_set_disconnected(cl);
return 0;
}
rets = pm_runtime_get(dev->dev);
if (rets < 0 && rets != -EINPROGRESS) {
pm_runtime_put_noidle(dev->dev);
cl_err(dev, cl, "rpm: get failed %d\n", rets);
return rets;
}
rets = __mei_cl_disconnect(cl);
cl_dbg(dev, cl, "rpm: autosuspend\n");
pm_runtime_mark_last_busy(dev->dev);
pm_runtime_put_autosuspend(dev->dev);
return rets;
}
/**
* mei_cl_is_other_connecting - checks if other
* client with the same me client id is connecting
*
* @cl: private data of the file object
*
* Return: true if other client is connected, false - otherwise.
*/
static bool mei_cl_is_other_connecting(struct mei_cl *cl)
{
struct mei_device *dev;
struct mei_cl_cb *cb;
dev = cl->dev;
list_for_each_entry(cb, &dev->ctrl_rd_list, list) {
if (cb->fop_type == MEI_FOP_CONNECT &&
mei_cl_me_id(cl) == mei_cl_me_id(cb->cl))
return true;
}
return false;
}
/**
* mei_cl_send_connect - send connect request
*
* @cl: host client
* @cb: callback block
*
* Return: 0, OK; otherwise, error.
*/
static int mei_cl_send_connect(struct mei_cl *cl, struct mei_cl_cb *cb)
{
struct mei_device *dev;
int ret;
dev = cl->dev;
ret = mei_hbm_cl_connect_req(dev, cl);
cl->status = ret;
if (ret) {
cl->state = MEI_FILE_DISCONNECT_REPLY;
return ret;
}
list_move_tail(&cb->list, &dev->ctrl_rd_list);
cl->timer_count = MEI_CONNECT_TIMEOUT;
mei_schedule_stall_timer(dev);
return 0;
}
/**
* mei_cl_irq_connect - send connect request in irq_thread context
*
* @cl: host client
* @cb: callback block
* @cmpl_list: complete list
*
* Return: 0, OK; otherwise, error.
*/
int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
struct list_head *cmpl_list)
{
struct mei_device *dev = cl->dev;
u32 msg_slots;
int slots;
int rets;
msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
slots = mei_hbuf_empty_slots(dev);
if (mei_cl_is_other_connecting(cl))
return 0;
if (slots < msg_slots)
return -EMSGSIZE;
rets = mei_cl_send_connect(cl, cb);
if (rets)
list_move_tail(&cb->list, cmpl_list);
return rets;
}
/**
* mei_cl_connect - connect host client to the me one
*
* @cl: host client
* @me_cl: me client
* @fp: pointer to file structure
*
* Locking: called under "dev->device_lock" lock
*
* Return: 0 on success, <0 on failure.
*/
int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
const struct file *fp)
{
struct mei_device *dev;
struct mei_cl_cb *cb;
int rets;
if (WARN_ON(!cl || !cl->dev || !me_cl))
return -ENODEV;
dev = cl->dev;
if (!mei_cl_bus_module_get(cl))
return -ENODEV;
rets = mei_cl_set_connecting(cl, me_cl);
if (rets)
goto nortpm;
if (mei_cl_is_fixed_address(cl)) {
cl->state = MEI_FILE_CONNECTED;
rets = 0;
goto nortpm;
}
rets = pm_runtime_get(dev->dev);
if (rets < 0 && rets != -EINPROGRESS) {
pm_runtime_put_noidle(dev->dev);
cl_err(dev, cl, "rpm: get failed %d\n", rets);
goto nortpm;
}
cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_CONNECT, fp);
if (!cb) {
rets = -ENOMEM;
goto out;
}
/* run hbuf acquire last so we don't have to undo */
if (!mei_cl_is_other_connecting(cl) && mei_hbuf_acquire(dev)) {
rets = mei_cl_send_connect(cl, cb);
if (rets)
goto out;
}
mutex_unlock(&dev->device_lock);
wait_event_timeout(cl->wait,
(cl->state == MEI_FILE_CONNECTED ||
cl->state == MEI_FILE_DISCONNECTED ||
cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
cl->state == MEI_FILE_DISCONNECT_REPLY),
mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
mutex_lock(&dev->device_lock);
if (!mei_cl_is_connected(cl)) {
if (cl->state == MEI_FILE_DISCONNECT_REQUIRED) {
mei_io_list_flush_cl(&dev->ctrl_rd_list, cl);
mei_io_list_flush_cl(&dev->ctrl_wr_list, cl);
/* ignore disconnect return valuue;
* in case of failure reset will be invoked
*/
__mei_cl_disconnect(cl);
rets = -EFAULT;
goto out;
}
/* timeout or something went really wrong */
if (!cl->status)
cl->status = -EFAULT;
}
rets = cl->status;
out:
cl_dbg(dev, cl, "rpm: autosuspend\n");
pm_runtime_mark_last_busy(dev->dev);
pm_runtime_put_autosuspend(dev->dev);
mei_io_cb_free(cb);
nortpm:
if (!mei_cl_is_connected(cl))
mei_cl_set_disconnected(cl);
return rets;
}
/**
* mei_cl_alloc_linked - allocate and link host client
*
* @dev: the device structure
*
* Return: cl on success ERR_PTR on failure
*/
struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev)
{
struct mei_cl *cl;
int ret;
cl = mei_cl_allocate(dev);
if (!cl) {
ret = -ENOMEM;
goto err;
}
ret = mei_cl_link(cl);
if (ret)
goto err;
return cl;
err:
kfree(cl);
return ERR_PTR(ret);
}
/**
* mei_cl_tx_flow_ctrl_creds - checks flow_control credits for cl.
*
* @cl: host client
*
* Return: 1 if tx_flow_ctrl_creds >0, 0 - otherwise.
*/
static int mei_cl_tx_flow_ctrl_creds(struct mei_cl *cl)
{
if (WARN_ON(!cl || !cl->me_cl))
return -EINVAL;
if (cl->tx_flow_ctrl_creds > 0)
return 1;
if (mei_cl_is_fixed_address(cl))
return 1;
if (mei_cl_is_single_recv_buf(cl)) {
if (cl->me_cl->tx_flow_ctrl_creds > 0)
return 1;
}
return 0;
}
/**
* mei_cl_tx_flow_ctrl_creds_reduce - reduces transmit flow control credits
* for a client
*
* @cl: host client
*
* Return:
* 0 on success
* -EINVAL when ctrl credits are <= 0
*/
static int mei_cl_tx_flow_ctrl_creds_reduce(struct mei_cl *cl)
{
if (WARN_ON(!cl || !cl->me_cl))
return -EINVAL;
if (mei_cl_is_fixed_address(cl))
return 0;
if (mei_cl_is_single_recv_buf(cl)) {
if (WARN_ON(cl->me_cl->tx_flow_ctrl_creds <= 0))
return -EINVAL;
cl->me_cl->tx_flow_ctrl_creds--;
} else {
if (WARN_ON(cl->tx_flow_ctrl_creds <= 0))
return -EINVAL;
cl->tx_flow_ctrl_creds--;
}
return 0;
}
/**
* mei_cl_notify_fop2req - convert fop to proper request
*
* @fop: client notification start response command
*
* Return: MEI_HBM_NOTIFICATION_START/STOP
*/
u8 mei_cl_notify_fop2req(enum mei_cb_file_ops fop)
{
if (fop == MEI_FOP_NOTIFY_START)
return MEI_HBM_NOTIFICATION_START;
else
return MEI_HBM_NOTIFICATION_STOP;
}
/**
* mei_cl_notify_req2fop - convert notification request top file operation type
*
* @req: hbm notification request type
*
* Return: MEI_FOP_NOTIFY_START/STOP
*/
enum mei_cb_file_ops mei_cl_notify_req2fop(u8 req)
{
if (req == MEI_HBM_NOTIFICATION_START)
return MEI_FOP_NOTIFY_START;
else
return MEI_FOP_NOTIFY_STOP;
}
/**
* mei_cl_irq_notify - send notification request in irq_thread context
*
* @cl: client
* @cb: callback block.
* @cmpl_list: complete list.
*
* Return: 0 on such and error otherwise.
*/
int mei_cl_irq_notify(struct mei_cl *cl, struct mei_cl_cb *cb,
struct list_head *cmpl_list)
{
struct mei_device *dev = cl->dev;
u32 msg_slots;
int slots;
int ret;
bool request;
msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
slots = mei_hbuf_empty_slots(dev);
if (slots < msg_slots)
return -EMSGSIZE;
request = mei_cl_notify_fop2req(cb->fop_type);
ret = mei_hbm_cl_notify_req(dev, cl, request);
if (ret) {
cl->status = ret;
list_move_tail(&cb->list, cmpl_list);
return ret;
}
list_move_tail(&cb->list, &dev->ctrl_rd_list);
return 0;
}
/**
* mei_cl_notify_request - send notification stop/start request
*
* @cl: host client
* @fp: associate request with file
* @request: 1 for start or 0 for stop
*
* Locking: called under "dev->device_lock" lock
*
* Return: 0 on such and error otherwise.
*/
int mei_cl_notify_request(struct mei_cl *cl,
const struct file *fp, u8 request)
{
struct mei_device *dev;
struct mei_cl_cb *cb;
enum mei_cb_file_ops fop_type;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
if (!dev->hbm_f_ev_supported) {
cl_dbg(dev, cl, "notifications not supported\n");
return -EOPNOTSUPP;
}
if (!mei_cl_is_connected(cl))
return -ENODEV;
rets = pm_runtime_get(dev->dev);
if (rets < 0 && rets != -EINPROGRESS) {
pm_runtime_put_noidle(dev->dev);
cl_err(dev, cl, "rpm: get failed %d\n", rets);
return rets;
}
fop_type = mei_cl_notify_req2fop(request);
cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, fop_type, fp);
if (!cb) {
rets = -ENOMEM;
goto out;
}
if (mei_hbuf_acquire(dev)) {
if (mei_hbm_cl_notify_req(dev, cl, request)) {
rets = -ENODEV;
goto out;
}
list_move_tail(&cb->list, &dev->ctrl_rd_list);
}
mutex_unlock(&dev->device_lock);
wait_event_timeout(cl->wait,
cl->notify_en == request || !mei_cl_is_connected(cl),
mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
mutex_lock(&dev->device_lock);
if (cl->notify_en != request && !cl->status)
cl->status = -EFAULT;
rets = cl->status;
out:
cl_dbg(dev, cl, "rpm: autosuspend\n");
pm_runtime_mark_last_busy(dev->dev);
pm_runtime_put_autosuspend(dev->dev);
mei_io_cb_free(cb);
return rets;
}
/**
* mei_cl_notify - raise notification
*
* @cl: host client
*
* Locking: called under "dev->device_lock" lock
*/
void mei_cl_notify(struct mei_cl *cl)
{
struct mei_device *dev;
if (!cl || !cl->dev)
return;
dev = cl->dev;
if (!cl->notify_en)
return;
cl_dbg(dev, cl, "notify event");
cl->notify_ev = true;
if (!mei_cl_bus_notify_event(cl))
wake_up_interruptible(&cl->ev_wait);
if (cl->ev_async)
kill_fasync(&cl->ev_async, SIGIO, POLL_PRI);
}
/**
* mei_cl_notify_get - get or wait for notification event
*
* @cl: host client
* @block: this request is blocking
* @notify_ev: true if notification event was received
*
* Locking: called under "dev->device_lock" lock
*
* Return: 0 on such and error otherwise.
*/
int mei_cl_notify_get(struct mei_cl *cl, bool block, bool *notify_ev)
{
struct mei_device *dev;
int rets;
*notify_ev = false;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
if (!dev->hbm_f_ev_supported) {
cl_dbg(dev, cl, "notifications not supported\n");
return -EOPNOTSUPP;
}
if (!mei_cl_is_connected(cl))
return -ENODEV;
if (cl->notify_ev)
goto out;
if (!block)
return -EAGAIN;
mutex_unlock(&dev->device_lock);
rets = wait_event_interruptible(cl->ev_wait, cl->notify_ev);
mutex_lock(&dev->device_lock);
if (rets < 0)
return rets;
out:
*notify_ev = cl->notify_ev;
cl->notify_ev = false;
return 0;
}
/**
* mei_cl_read_start - the start read client message function.
*
* @cl: host client
* @length: number of bytes to read
* @fp: pointer to file structure
*
* Return: 0 on success, <0 on failure.
*/
int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp)
{
struct mei_device *dev;
struct mei_cl_cb *cb;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
if (!mei_cl_is_connected(cl))
return -ENODEV;
if (!mei_me_cl_is_active(cl->me_cl)) {
cl_err(dev, cl, "no such me client\n");
return -ENOTTY;
}
if (mei_cl_is_fixed_address(cl))
return 0;
/* HW currently supports only one pending read */
if (cl->rx_flow_ctrl_creds)
return -EBUSY;
cb = mei_cl_enqueue_ctrl_wr_cb(cl, length, MEI_FOP_READ, fp);
if (!cb)
return -ENOMEM;
rets = pm_runtime_get(dev->dev);
if (rets < 0 && rets != -EINPROGRESS) {
pm_runtime_put_noidle(dev->dev);
cl_err(dev, cl, "rpm: get failed %d\n", rets);
goto nortpm;
}
rets = 0;
if (mei_hbuf_acquire(dev)) {
rets = mei_hbm_cl_flow_control_req(dev, cl);
if (rets < 0)
goto out;
list_move_tail(&cb->list, &cl->rd_pending);
}
cl->rx_flow_ctrl_creds++;
out:
cl_dbg(dev, cl, "rpm: autosuspend\n");
pm_runtime_mark_last_busy(dev->dev);
pm_runtime_put_autosuspend(dev->dev);
nortpm:
if (rets)
mei_io_cb_free(cb);
return rets;
}
/**
* mei_cl_irq_write - write a message to device
* from the interrupt thread context
*
* @cl: client
* @cb: callback block.
* @cmpl_list: complete list.
*
* Return: 0, OK; otherwise error.
*/
int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
struct list_head *cmpl_list)
{
struct mei_device *dev;
struct mei_msg_data *buf;
struct mei_msg_hdr mei_hdr;
size_t len;
u32 msg_slots;
int slots;
int rets;
bool first_chunk;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
buf = &cb->buf;
first_chunk = cb->buf_idx == 0;
rets = first_chunk ? mei_cl_tx_flow_ctrl_creds(cl) : 1;
if (rets < 0)
goto err;
if (rets == 0) {
cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
return 0;
}
slots = mei_hbuf_empty_slots(dev);
len = buf->size - cb->buf_idx;
msg_slots = mei_data2slots(len);
mei_hdr.host_addr = mei_cl_host_addr(cl);
mei_hdr.me_addr = mei_cl_me_id(cl);
mei_hdr.reserved = 0;
mei_hdr.internal = cb->internal;
if (slots >= msg_slots) {
mei_hdr.length = len;
mei_hdr.msg_complete = 1;
/* Split the message only if we can write the whole host buffer */
} else if (slots == dev->hbuf_depth) {
msg_slots = slots;
len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
mei_hdr.length = len;
mei_hdr.msg_complete = 0;
} else {
/* wait for next time the host buffer is empty */
return 0;
}
cl_dbg(dev, cl, "buf: size = %zu idx = %zu\n",
cb->buf.size, cb->buf_idx);
rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
if (rets)
goto err;
cl->status = 0;
cl->writing_state = MEI_WRITING;
cb->buf_idx += mei_hdr.length;
cb->completed = mei_hdr.msg_complete == 1;
if (first_chunk) {
if (mei_cl_tx_flow_ctrl_creds_reduce(cl)) {
rets = -EIO;
goto err;
}
}
if (mei_hdr.msg_complete)
list_move_tail(&cb->list, &dev->write_waiting_list);
return 0;
err:
cl->status = rets;
list_move_tail(&cb->list, cmpl_list);
return rets;
}
/**
* mei_cl_write - submit a write cb to mei device
* assumes device_lock is locked
*
* @cl: host client
* @cb: write callback with filled data
*
* Return: number of bytes sent on success, <0 on failure.
*/
int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
{
struct mei_device *dev;
struct mei_msg_data *buf;
struct mei_msg_hdr mei_hdr;
int size;
int rets;
bool blocking;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
if (WARN_ON(!cb))
return -EINVAL;
dev = cl->dev;
buf = &cb->buf;
size = buf->size;
blocking = cb->blocking;
cl_dbg(dev, cl, "size=%d\n", size);
rets = pm_runtime_get(dev->dev);
if (rets < 0 && rets != -EINPROGRESS) {
pm_runtime_put_noidle(dev->dev);
cl_err(dev, cl, "rpm: get failed %d\n", rets);
goto free;
}
cb->buf_idx = 0;
cl->writing_state = MEI_IDLE;
mei_hdr.host_addr = mei_cl_host_addr(cl);
mei_hdr.me_addr = mei_cl_me_id(cl);
mei_hdr.reserved = 0;
mei_hdr.msg_complete = 0;
mei_hdr.internal = cb->internal;
rets = mei_cl_tx_flow_ctrl_creds(cl);
if (rets < 0)
goto err;
if (rets == 0) {
cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
rets = size;
goto out;
}
if (!mei_hbuf_acquire(dev)) {
cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
rets = size;
goto out;
}
/* Check for a maximum length */
if (size > mei_hbuf_max_len(dev)) {
mei_hdr.length = mei_hbuf_max_len(dev);
mei_hdr.msg_complete = 0;
} else {
mei_hdr.length = size;
mei_hdr.msg_complete = 1;
}
rets = mei_write_message(dev, &mei_hdr, buf->data);
if (rets)
goto err;
rets = mei_cl_tx_flow_ctrl_creds_reduce(cl);
if (rets)
goto err;
cl->writing_state = MEI_WRITING;
cb->buf_idx = mei_hdr.length;
cb->completed = mei_hdr.msg_complete == 1;
out:
if (mei_hdr.msg_complete)
list_add_tail(&cb->list, &dev->write_waiting_list);
else
list_add_tail(&cb->list, &dev->write_list);
cb = NULL;
if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
mutex_unlock(&dev->device_lock);
rets = wait_event_interruptible(cl->tx_wait,
cl->writing_state == MEI_WRITE_COMPLETE ||
(!mei_cl_is_connected(cl)));
mutex_lock(&dev->device_lock);
/* wait_event_interruptible returns -ERESTARTSYS */
if (rets) {
if (signal_pending(current))
rets = -EINTR;
goto err;
}
if (cl->writing_state != MEI_WRITE_COMPLETE) {
rets = -EFAULT;
goto err;
}
}
rets = size;
err:
cl_dbg(dev, cl, "rpm: autosuspend\n");
pm_runtime_mark_last_busy(dev->dev);
pm_runtime_put_autosuspend(dev->dev);
free:
mei_io_cb_free(cb);
return rets;
}
/**
* mei_cl_complete - processes completed operation for a client
*
* @cl: private data of the file object.
* @cb: callback block.
*/
void mei_cl_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
{
struct mei_device *dev = cl->dev;
switch (cb->fop_type) {
case MEI_FOP_WRITE:
mei_io_cb_free(cb);
cl->writing_state = MEI_WRITE_COMPLETE;
if (waitqueue_active(&cl->tx_wait)) {
wake_up_interruptible(&cl->tx_wait);
} else {
pm_runtime_mark_last_busy(dev->dev);
pm_request_autosuspend(dev->dev);
}
break;
case MEI_FOP_READ:
list_add_tail(&cb->list, &cl->rd_completed);
if (!mei_cl_is_fixed_address(cl) &&
!WARN_ON(!cl->rx_flow_ctrl_creds))
cl->rx_flow_ctrl_creds--;
if (!mei_cl_bus_rx_event(cl))
wake_up_interruptible(&cl->rx_wait);
break;
case MEI_FOP_CONNECT:
case MEI_FOP_DISCONNECT:
case MEI_FOP_NOTIFY_STOP:
case MEI_FOP_NOTIFY_START:
if (waitqueue_active(&cl->wait))
wake_up(&cl->wait);
break;
case MEI_FOP_DISCONNECT_RSP:
mei_io_cb_free(cb);
mei_cl_set_disconnected(cl);
break;
default:
BUG_ON(0);
}
}
/**
* mei_cl_all_disconnect - disconnect forcefully all connected clients
*
* @dev: mei device
*/
void mei_cl_all_disconnect(struct mei_device *dev)
{
struct mei_cl *cl;
list_for_each_entry(cl, &dev->file_list, link)
mei_cl_set_disconnected(cl);
}