linux/drivers/misc/mei/client.c

950 lines
20 KiB
C

/*
*
* 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/pci.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <linux/mei.h>
#include "mei_dev.h"
#include "hbm.h"
#include "client.h"
/**
* mei_me_cl_by_uuid - locate index of me client
*
* @dev: mei device
* returns me client index or -ENOENT if not found
*/
int mei_me_cl_by_uuid(const struct mei_device *dev, const uuid_le *uuid)
{
int i, res = -ENOENT;
for (i = 0; i < dev->me_clients_num; ++i)
if (uuid_le_cmp(*uuid,
dev->me_clients[i].props.protocol_name) == 0) {
res = i;
break;
}
return res;
}
/**
* mei_me_cl_by_id return index to me_clients for client_id
*
* @dev: the device structure
* @client_id: me client id
*
* Locking: called under "dev->device_lock" lock
*
* returns index on success, -ENOENT on failure.
*/
int mei_me_cl_by_id(struct mei_device *dev, u8 client_id)
{
int i;
for (i = 0; i < dev->me_clients_num; i++)
if (dev->me_clients[i].client_id == client_id)
break;
if (WARN_ON(dev->me_clients[i].client_id != client_id))
return -ENOENT;
if (i == dev->me_clients_num)
return -ENOENT;
return i;
}
/**
* mei_io_list_flush - removes list entry belonging to cl.
*
* @list: An instance of our list structure
* @cl: host client
*/
void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
{
struct mei_cl_cb *cb;
struct mei_cl_cb *next;
list_for_each_entry_safe(cb, next, &list->list, list) {
if (cb->cl && mei_cl_cmp_id(cl, cb->cl))
list_del(&cb->list);
}
}
/**
* 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;
kfree(cb->request_buffer.data);
kfree(cb->response_buffer.data);
kfree(cb);
}
/**
* mei_io_cb_init - allocate and initialize io callback
*
* @cl - mei client
* @fp: pointer to file structure
*
* returns mei_cl_cb pointer or NULL;
*/
struct mei_cl_cb *mei_io_cb_init(struct mei_cl *cl, struct file *fp)
{
struct mei_cl_cb *cb;
cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
if (!cb)
return NULL;
mei_io_list_init(cb);
cb->file_object = fp;
cb->cl = cl;
cb->buf_idx = 0;
return cb;
}
/**
* mei_io_cb_alloc_req_buf - allocate request buffer
*
* @cb: io callback structure
* @length: size of the buffer
*
* returns 0 on success
* -EINVAL if cb is NULL
* -ENOMEM if allocation failed
*/
int mei_io_cb_alloc_req_buf(struct mei_cl_cb *cb, size_t length)
{
if (!cb)
return -EINVAL;
if (length == 0)
return 0;
cb->request_buffer.data = kmalloc(length, GFP_KERNEL);
if (!cb->request_buffer.data)
return -ENOMEM;
cb->request_buffer.size = length;
return 0;
}
/**
* mei_io_cb_alloc_resp_buf - allocate respose buffer
*
* @cb: io callback structure
* @length: size of the buffer
*
* returns 0 on success
* -EINVAL if cb is NULL
* -ENOMEM if allocation failed
*/
int mei_io_cb_alloc_resp_buf(struct mei_cl_cb *cb, size_t length)
{
if (!cb)
return -EINVAL;
if (length == 0)
return 0;
cb->response_buffer.data = kmalloc(length, GFP_KERNEL);
if (!cb->response_buffer.data)
return -ENOMEM;
cb->response_buffer.size = length;
return 0;
}
/**
* mei_cl_flush_queues - flushes queue lists belonging to cl.
*
* @cl: host client
*/
int mei_cl_flush_queues(struct mei_cl *cl)
{
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_flush(&cl->dev->read_list, cl);
mei_io_list_flush(&cl->dev->write_list, cl);
mei_io_list_flush(&cl->dev->write_waiting_list, cl);
mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
mei_io_list_flush(&cl->dev->amthif_rd_complete_list, cl);
return 0;
}
/**
* mei_cl_init - initializes intialize cl.
*
* @cl: host client to be initialized
* @dev: mei device
*/
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_LIST_HEAD(&cl->link);
INIT_LIST_HEAD(&cl->device_link);
cl->reading_state = MEI_IDLE;
cl->writing_state = MEI_IDLE;
cl->dev = dev;
}
/**
* mei_cl_allocate - allocates cl structure and sets it up.
*
* @dev: mei device
* returns 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_find_read_cb - find this cl's callback in the read list
*
* @cl: host client
*
* returns cb on success, NULL on error
*/
struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl)
{
struct mei_device *dev = cl->dev;
struct mei_cl_cb *cb = NULL;
struct mei_cl_cb *next = NULL;
list_for_each_entry_safe(cb, next, &dev->read_list.list, list)
if (mei_cl_cmp_id(cl, cb->cl))
return cb;
return NULL;
}
/** mei_cl_link: allocte host id in the host map
*
* @cl - host client
* @id - fixed host id or -1 for genereting one
*
* returns 0 on success
* -EINVAL on incorrect values
* -ENONET if client not found
*/
int mei_cl_link(struct mei_cl *cl, int id)
{
struct mei_device *dev;
if (WARN_ON(!cl || !cl->dev))
return -EINVAL;
dev = cl->dev;
/* If Id is not asigned get one*/
if (id == MEI_HOST_CLIENT_ID_ANY)
id = find_first_zero_bit(dev->host_clients_map,
MEI_CLIENTS_MAX);
if (id >= MEI_CLIENTS_MAX) {
dev_err(&dev->pdev->dev, "id exceded %d", MEI_CLIENTS_MAX) ;
return -ENOENT;
}
if (dev->open_handle_count >= MEI_MAX_OPEN_HANDLE_COUNT) {
dev_err(&dev->pdev->dev, "open_handle_count exceded %d",
MEI_MAX_OPEN_HANDLE_COUNT);
return -ENOENT;
}
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 me_cl from the list
*
* @cl: host client
*/
int mei_cl_unlink(struct mei_cl *cl)
{
struct mei_device *dev;
/* don't shout on error exit path */
if (!cl)
return 0;
/* wd and amthif might not be initialized */
if (!cl->dev)
return 0;
dev = cl->dev;
cl_dbg(dev, cl, "unlink client");
list_del_init(&cl->link);
return 0;
}
void mei_host_client_init(struct work_struct *work)
{
struct mei_device *dev = container_of(work,
struct mei_device, init_work);
struct mei_client_properties *client_props;
int i;
mutex_lock(&dev->device_lock);
bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
dev->open_handle_count = 0;
/*
* Reserving the first three client IDs
* 0: Reserved for MEI Bus Message communications
* 1: Reserved for Watchdog
* 2: Reserved for AMTHI
*/
bitmap_set(dev->host_clients_map, 0, 3);
for (i = 0; i < dev->me_clients_num; i++) {
client_props = &dev->me_clients[i].props;
if (!uuid_le_cmp(client_props->protocol_name, mei_amthif_guid))
mei_amthif_host_init(dev);
else if (!uuid_le_cmp(client_props->protocol_name, mei_wd_guid))
mei_wd_host_init(dev);
else if (!uuid_le_cmp(client_props->protocol_name, mei_nfc_guid))
mei_nfc_host_init(dev);
}
dev->dev_state = MEI_DEV_ENABLED;
mutex_unlock(&dev->device_lock);
}
/**
* mei_cl_disconnect - disconnect host clinet form the me one
*
* @cl: host client
*
* Locking: called under "dev->device_lock" lock
*
* returns 0 on success, <0 on failure.
*/
int mei_cl_disconnect(struct mei_cl *cl)
{
struct mei_device *dev;
struct mei_cl_cb *cb;
int rets, err;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
cl_dbg(dev, cl, "disconnecting");
if (cl->state != MEI_FILE_DISCONNECTING)
return 0;
cb = mei_io_cb_init(cl, NULL);
if (!cb)
return -ENOMEM;
cb->fop_type = MEI_FOP_CLOSE;
if (dev->hbuf_is_ready) {
dev->hbuf_is_ready = false;
if (mei_hbm_cl_disconnect_req(dev, cl)) {
rets = -ENODEV;
cl_err(dev, cl, "failed to disconnect.\n");
goto free;
}
mdelay(10); /* Wait for hardware disconnection ready */
list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
} else {
cl_dbg(dev, cl, "add disconnect cb to control write list\n");
list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
}
mutex_unlock(&dev->device_lock);
err = wait_event_timeout(dev->wait_recvd_msg,
MEI_FILE_DISCONNECTED == cl->state,
mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
mutex_lock(&dev->device_lock);
if (MEI_FILE_DISCONNECTED == cl->state) {
rets = 0;
cl_dbg(dev, cl, "successfully disconnected from FW client.\n");
} else {
rets = -ENODEV;
if (MEI_FILE_DISCONNECTED != cl->state)
cl_err(dev, cl, "wrong status client disconnect.\n");
if (err)
cl_dbg(dev, cl, "wait failed disconnect err=%08x\n",
err);
cl_err(dev, cl, "failed to disconnect from FW client.\n");
}
mei_io_list_flush(&dev->ctrl_rd_list, cl);
mei_io_list_flush(&dev->ctrl_wr_list, cl);
free:
mei_io_cb_free(cb);
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
*
* returns ture if other client is connected, 0 - otherwise.
*/
bool mei_cl_is_other_connecting(struct mei_cl *cl)
{
struct mei_device *dev;
struct mei_cl *pos;
struct mei_cl *next;
if (WARN_ON(!cl || !cl->dev))
return false;
dev = cl->dev;
list_for_each_entry_safe(pos, next, &dev->file_list, link) {
if ((pos->state == MEI_FILE_CONNECTING) &&
(pos != cl) && cl->me_client_id == pos->me_client_id)
return true;
}
return false;
}
/**
* mei_cl_connect - connect host clinet to the me one
*
* @cl: host client
*
* Locking: called under "dev->device_lock" lock
*
* returns 0 on success, <0 on failure.
*/
int mei_cl_connect(struct mei_cl *cl, struct file *file)
{
struct mei_device *dev;
struct mei_cl_cb *cb;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
cb = mei_io_cb_init(cl, file);
if (!cb) {
rets = -ENOMEM;
goto out;
}
cb->fop_type = MEI_FOP_IOCTL;
if (dev->hbuf_is_ready && !mei_cl_is_other_connecting(cl)) {
dev->hbuf_is_ready = false;
if (mei_hbm_cl_connect_req(dev, cl)) {
rets = -ENODEV;
goto out;
}
cl->timer_count = MEI_CONNECT_TIMEOUT;
list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
} else {
list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
}
mutex_unlock(&dev->device_lock);
rets = wait_event_timeout(dev->wait_recvd_msg,
(cl->state == MEI_FILE_CONNECTED ||
cl->state == MEI_FILE_DISCONNECTED),
mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
mutex_lock(&dev->device_lock);
if (cl->state != MEI_FILE_CONNECTED) {
rets = -EFAULT;
mei_io_list_flush(&dev->ctrl_rd_list, cl);
mei_io_list_flush(&dev->ctrl_wr_list, cl);
goto out;
}
rets = cl->status;
out:
mei_io_cb_free(cb);
return rets;
}
/**
* mei_cl_flow_ctrl_creds - checks flow_control credits for cl.
*
* @cl: private data of the file object
*
* returns 1 if mei_flow_ctrl_creds >0, 0 - otherwise.
* -ENOENT if mei_cl is not present
* -EINVAL if single_recv_buf == 0
*/
int mei_cl_flow_ctrl_creds(struct mei_cl *cl)
{
struct mei_device *dev;
int i;
if (WARN_ON(!cl || !cl->dev))
return -EINVAL;
dev = cl->dev;
if (!dev->me_clients_num)
return 0;
if (cl->mei_flow_ctrl_creds > 0)
return 1;
for (i = 0; i < dev->me_clients_num; i++) {
struct mei_me_client *me_cl = &dev->me_clients[i];
if (me_cl->client_id == cl->me_client_id) {
if (me_cl->mei_flow_ctrl_creds) {
if (WARN_ON(me_cl->props.single_recv_buf == 0))
return -EINVAL;
return 1;
} else {
return 0;
}
}
}
return -ENOENT;
}
/**
* mei_cl_flow_ctrl_reduce - reduces flow_control.
*
* @cl: private data of the file object
*
* @returns
* 0 on success
* -ENOENT when me client is not found
* -EINVAL when ctrl credits are <= 0
*/
int mei_cl_flow_ctrl_reduce(struct mei_cl *cl)
{
struct mei_device *dev;
int i;
if (WARN_ON(!cl || !cl->dev))
return -EINVAL;
dev = cl->dev;
if (!dev->me_clients_num)
return -ENOENT;
for (i = 0; i < dev->me_clients_num; i++) {
struct mei_me_client *me_cl = &dev->me_clients[i];
if (me_cl->client_id == cl->me_client_id) {
if (me_cl->props.single_recv_buf != 0) {
if (WARN_ON(me_cl->mei_flow_ctrl_creds <= 0))
return -EINVAL;
dev->me_clients[i].mei_flow_ctrl_creds--;
} else {
if (WARN_ON(cl->mei_flow_ctrl_creds <= 0))
return -EINVAL;
cl->mei_flow_ctrl_creds--;
}
return 0;
}
}
return -ENOENT;
}
/**
* mei_cl_read_start - the start read client message function.
*
* @cl: host client
*
* returns 0 on success, <0 on failure.
*/
int mei_cl_read_start(struct mei_cl *cl, size_t length)
{
struct mei_device *dev;
struct mei_cl_cb *cb;
int rets;
int i;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
if (!mei_cl_is_connected(cl))
return -ENODEV;
if (cl->read_cb) {
cl_dbg(dev, cl, "read is pending.\n");
return -EBUSY;
}
i = mei_me_cl_by_id(dev, cl->me_client_id);
if (i < 0) {
cl_err(dev, cl, "no such me client %d\n", cl->me_client_id);
return -ENODEV;
}
cb = mei_io_cb_init(cl, NULL);
if (!cb)
return -ENOMEM;
/* always allocate at least client max message */
length = max_t(size_t, length, dev->me_clients[i].props.max_msg_length);
rets = mei_io_cb_alloc_resp_buf(cb, length);
if (rets)
goto err;
cb->fop_type = MEI_FOP_READ;
cl->read_cb = cb;
if (dev->hbuf_is_ready) {
dev->hbuf_is_ready = false;
if (mei_hbm_cl_flow_control_req(dev, cl)) {
cl_err(dev, cl, "flow control send failed\n");
rets = -ENODEV;
goto err;
}
list_add_tail(&cb->list, &dev->read_list.list);
} else {
list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
}
return rets;
err:
mei_io_cb_free(cb);
return rets;
}
/**
* mei_cl_irq_write_complete - write a message to device
* from the interrupt thread context
*
* @cl: client
* @cb: callback block.
* @slots: free slots.
* @cmpl_list: complete list.
*
* returns 0, OK; otherwise error.
*/
int mei_cl_irq_write_complete(struct mei_cl *cl, struct mei_cl_cb *cb,
s32 *slots, struct mei_cl_cb *cmpl_list)
{
struct mei_device *dev;
struct mei_msg_data *buf;
struct mei_msg_hdr mei_hdr;
size_t len;
u32 msg_slots;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
buf = &cb->request_buffer;
rets = mei_cl_flow_ctrl_creds(cl);
if (rets < 0)
return rets;
if (rets == 0) {
cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
return 0;
}
len = buf->size - cb->buf_idx;
msg_slots = mei_data2slots(len);
mei_hdr.host_addr = cl->host_client_id;
mei_hdr.me_addr = cl->me_client_id;
mei_hdr.reserved = 0;
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 = %d idx = %lu\n",
cb->request_buffer.size, cb->buf_idx);
*slots -= msg_slots;
rets = mei_write_message(dev, &mei_hdr, buf->data + cb->buf_idx);
if (rets) {
cl->status = rets;
list_move_tail(&cb->list, &cmpl_list->list);
return rets;
}
cl->status = 0;
cl->writing_state = MEI_WRITING;
cb->buf_idx += mei_hdr.length;
if (mei_hdr.msg_complete) {
if (mei_cl_flow_ctrl_reduce(cl))
return -EIO;
list_move_tail(&cb->list, &dev->write_waiting_list.list);
}
return 0;
}
/**
* mei_cl_write - submit a write cb to mei device
assumes device_lock is locked
*
* @cl: host client
* @cl: write callback with filled data
*
* returns numbe of bytes sent on success, <0 on failure.
*/
int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb, bool blocking)
{
struct mei_device *dev;
struct mei_msg_data *buf;
struct mei_msg_hdr mei_hdr;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
if (WARN_ON(!cb))
return -EINVAL;
dev = cl->dev;
buf = &cb->request_buffer;
cl_dbg(dev, cl, "mei_cl_write %d\n", buf->size);
cb->fop_type = MEI_FOP_WRITE;
rets = mei_cl_flow_ctrl_creds(cl);
if (rets < 0)
goto err;
/* Host buffer is not ready, we queue the request */
if (rets == 0 || !dev->hbuf_is_ready) {
cb->buf_idx = 0;
/* unseting complete will enqueue the cb for write */
mei_hdr.msg_complete = 0;
rets = buf->size;
goto out;
}
dev->hbuf_is_ready = false;
/* Check for a maximum length */
if (buf->size > mei_hbuf_max_len(dev)) {
mei_hdr.length = mei_hbuf_max_len(dev);
mei_hdr.msg_complete = 0;
} else {
mei_hdr.length = buf->size;
mei_hdr.msg_complete = 1;
}
mei_hdr.host_addr = cl->host_client_id;
mei_hdr.me_addr = cl->me_client_id;
mei_hdr.reserved = 0;
rets = mei_write_message(dev, &mei_hdr, buf->data);
if (rets)
goto err;
cl->writing_state = MEI_WRITING;
cb->buf_idx = mei_hdr.length;
rets = buf->size;
out:
if (mei_hdr.msg_complete) {
if (mei_cl_flow_ctrl_reduce(cl)) {
rets = -ENODEV;
goto err;
}
list_add_tail(&cb->list, &dev->write_waiting_list.list);
} else {
list_add_tail(&cb->list, &dev->write_list.list);
}
if (blocking && cl->writing_state != MEI_WRITE_COMPLETE) {
mutex_unlock(&dev->device_lock);
if (wait_event_interruptible(cl->tx_wait,
cl->writing_state == MEI_WRITE_COMPLETE)) {
if (signal_pending(current))
rets = -EINTR;
else
rets = -ERESTARTSYS;
}
mutex_lock(&dev->device_lock);
}
err:
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)
{
if (cb->fop_type == MEI_FOP_WRITE) {
mei_io_cb_free(cb);
cb = NULL;
cl->writing_state = MEI_WRITE_COMPLETE;
if (waitqueue_active(&cl->tx_wait))
wake_up_interruptible(&cl->tx_wait);
} else if (cb->fop_type == MEI_FOP_READ &&
MEI_READING == cl->reading_state) {
cl->reading_state = MEI_READ_COMPLETE;
if (waitqueue_active(&cl->rx_wait))
wake_up_interruptible(&cl->rx_wait);
else
mei_cl_bus_rx_event(cl);
}
}
/**
* 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, *next;
list_for_each_entry_safe(cl, next, &dev->file_list, link) {
cl->state = MEI_FILE_DISCONNECTED;
cl->mei_flow_ctrl_creds = 0;
cl->read_cb = NULL;
cl->timer_count = 0;
}
}
/**
* mei_cl_all_wakeup - wake up all readers and writers they can be interrupted
*
* @dev - mei device
*/
void mei_cl_all_wakeup(struct mei_device *dev)
{
struct mei_cl *cl, *next;
list_for_each_entry_safe(cl, next, &dev->file_list, link) {
if (waitqueue_active(&cl->rx_wait)) {
cl_dbg(dev, cl, "Waking up reading client!\n");
wake_up_interruptible(&cl->rx_wait);
}
if (waitqueue_active(&cl->tx_wait)) {
cl_dbg(dev, cl, "Waking up writing client!\n");
wake_up_interruptible(&cl->tx_wait);
}
}
}
/**
* mei_cl_all_write_clear - clear all pending writes
* @dev - mei device
*/
void mei_cl_all_write_clear(struct mei_device *dev)
{
struct mei_cl_cb *cb, *next;
list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
list_del(&cb->list);
mei_io_cb_free(cb);
}
}