/**
* mei_amthif_complete - complete amthif callback.
*
* @cl: host client
* @cb: callback block.
*/
void mei_amthif_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
{
struct mei_device *dev = cl->dev;
if (cb->fop_type == MEI_FOP_WRITE) {
if (!cb->status) {
dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
mei_io_cb_free(cb);
return;
}
/*
* in case of error enqueue the write cb to complete read list
* so it can be propagated to the reader
*/
list_add_tail(&cb->list, &cl->rd_completed);
wake_up_interruptible(&cl->rx_wait);
return;
}
if (!dev->iamthif_canceled) {
dev->iamthif_state = MEI_IAMTHIF_READ_COMPLETE;
dev->iamthif_stall_timer = 0;
list_add_tail(&cb->list, &cl->rd_completed);
dev_dbg(dev->dev, "amthif read completed\n");
} else {
mei_amthif_run_next_cmd(dev);
}
dev_dbg(dev->dev, "completing amthif call back.\n");
wake_up_interruptible(&cl->rx_wait);
}
/**
* mei_clear_lists - removes all callbacks associated with file
*
* @dev: device structure
* @file: file structure
*
* mei_clear_lists is called to clear resources associated with file
* when application calls close function or Ctrl-C was pressed
*
* Return: true if callback removed from the list, false otherwise
*/
static bool mei_clear_lists(struct mei_device *dev, const struct file *file)
{
bool removed = false;
struct mei_cl *cl = &dev->iamthif_cl;
/* remove callbacks associated with a file */
mei_clear_list(dev, file, &dev->amthif_cmd_list.list);
if (mei_clear_list(dev, file, &cl->rd_completed))
removed = true;
mei_clear_list(dev, file, &dev->ctrl_rd_list.list);
if (mei_clear_list(dev, file, &dev->ctrl_wr_list.list))
removed = true;
if (mei_clear_list(dev, file, &dev->write_waiting_list.list))
removed = true;
if (mei_clear_list(dev, file, &dev->write_list.list))
removed = true;
/* check if iamthif_current_cb not NULL */
if (dev->iamthif_current_cb && !removed) {
/* check file and iamthif current cb association */
if (dev->iamthif_current_cb->fp == file) {
/* remove cb */
mei_io_cb_free(dev->iamthif_current_cb);
dev->iamthif_current_cb = NULL;
removed = true;
}
}
return removed;
}
/**
* mei_amthif_read_start - queue message for sending read credential
*
* @cl: host client
* @file: file pointer of message recipient
*
* Return: 0 on success, <0 on failure.
*/
static int mei_amthif_read_start(struct mei_cl *cl, const struct file *file)
{
struct mei_device *dev = cl->dev;
struct mei_cl_cb *cb;
int rets;
cb = mei_io_cb_init(cl, MEI_FOP_READ, file);
if (!cb) {
rets = -ENOMEM;
goto err;
}
rets = mei_io_cb_alloc_buf(cb, mei_cl_mtu(cl));
if (rets)
goto err;
list_add_tail(&cb->list, &dev->ctrl_wr_list.list);
dev->iamthif_state = MEI_IAMTHIF_READING;
dev->iamthif_fp = cb->fp;
dev->iamthif_current_cb = cb;
return 0;
err:
mei_io_cb_free(cb);
return rets;
}
/**
* mei_release - the release function
*
* @inode: pointer to inode structure
* @file: pointer to file structure
*
* returns 0 on success, <0 on error
*/
static int mei_release(struct inode *inode, struct file *file)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *cb;
struct mei_device *dev;
int rets = 0;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (cl == &dev->iamthif_cl) {
rets = mei_amthif_release(dev, file);
goto out;
}
if (cl->state == MEI_FILE_CONNECTED) {
cl->state = MEI_FILE_DISCONNECTING;
dev_dbg(&dev->pdev->dev,
"disconnecting client host client = %d, "
"ME client = %d\n",
cl->host_client_id,
cl->me_client_id);
rets = mei_cl_disconnect(cl);
}
mei_cl_flush_queues(cl);
dev_dbg(&dev->pdev->dev, "remove client host client = %d, ME client = %d\n",
cl->host_client_id,
cl->me_client_id);
mei_cl_unlink(cl);
/* free read cb */
cb = NULL;
if (cl->read_cb) {
cb = mei_cl_find_read_cb(cl);
/* Remove entry from read list */
if (cb)
list_del(&cb->list);
cb = cl->read_cb;
cl->read_cb = NULL;
}
file->private_data = NULL;
mei_io_cb_free(cb);
kfree(cl);
out:
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_clear_list - removes all callbacks associated with file
* from mei_cb_list
*
* @dev: device structure.
* @file: file structure
* @mei_cb_list: callbacks list
*
* mei_clear_list is called to clear resources associated with file
* when application calls close function or Ctrl-C was pressed
*
* Return: true if callback removed from the list, false otherwise
*/
static bool mei_clear_list(struct mei_device *dev,
const struct file *file, struct list_head *mei_cb_list)
{
struct mei_cl *cl = &dev->iamthif_cl;
struct mei_cl_cb *cb, *next;
bool removed = false;
/* list all list member */
list_for_each_entry_safe(cb, next, mei_cb_list, list) {
/* check if list member associated with a file */
if (file == cb->fp) {
/* check if cb equal to current iamthif cb */
if (dev->iamthif_current_cb == cb) {
dev->iamthif_current_cb = NULL;
/* send flow control to iamthif client */
mei_hbm_cl_flow_control_req(dev, cl);
}
/* free all allocated buffers */
mei_io_cb_free(cb);
removed = true;
}
}
return removed;
}
/**
* mei_write - the write function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* returns >=0 data length on success , <0 on error
*/
static ssize_t mei_write(struct file *file, const char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *write_cb = NULL;
struct mei_device *dev;
unsigned long timeout = 0;
int rets;
int id;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
id = mei_me_cl_by_id(dev, cl->me_client_id);
if (id < 0) {
rets = -ENOTTY;
goto out;
}
if (length == 0) {
rets = 0;
goto out;
}
if (length > dev->me_clients[id].props.max_msg_length) {
rets = -EFBIG;
goto out;
}
if (cl->state != MEI_FILE_CONNECTED) {
dev_err(&dev->pdev->dev, "host client = %d, is not connected to ME client = %d",
cl->host_client_id, cl->me_client_id);
rets = -ENODEV;
goto out;
}
if (cl == &dev->iamthif_cl) {
write_cb = mei_amthif_find_read_list_entry(dev, file);
if (write_cb) {
timeout = write_cb->read_time +
mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
if (time_after(jiffies, timeout) ||
cl->reading_state == MEI_READ_COMPLETE) {
*offset = 0;
list_del(&write_cb->list);
mei_io_cb_free(write_cb);
write_cb = NULL;
}
}
}
/* free entry used in read */
if (cl->reading_state == MEI_READ_COMPLETE) {
*offset = 0;
write_cb = mei_cl_find_read_cb(cl);
if (write_cb) {
list_del(&write_cb->list);
mei_io_cb_free(write_cb);
write_cb = NULL;
cl->reading_state = MEI_IDLE;
cl->read_cb = NULL;
}
} else if (cl->reading_state == MEI_IDLE)
*offset = 0;
write_cb = mei_io_cb_init(cl, file);
if (!write_cb) {
dev_err(&dev->pdev->dev, "write cb allocation failed\n");
rets = -ENOMEM;
goto out;
}
rets = mei_io_cb_alloc_req_buf(write_cb, length);
if (rets)
goto out;
rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
if (rets) {
dev_dbg(&dev->pdev->dev, "failed to copy data from userland\n");
rets = -EFAULT;
goto out;
}
if (cl == &dev->iamthif_cl) {
rets = mei_amthif_write(dev, write_cb);
if (rets) {
dev_err(&dev->pdev->dev,
"amthif write failed with status = %d\n", rets);
goto out;
}
mutex_unlock(&dev->device_lock);
return length;
}
rets = mei_cl_write(cl, write_cb, false);
out:
mutex_unlock(&dev->device_lock);
if (rets < 0)
mei_io_cb_free(write_cb);
return rets;
}
/**
* mei_read - the read function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* returns >=0 data length on success , <0 on error
*/
static ssize_t mei_read(struct file *file, char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *cb_pos = NULL;
struct mei_cl_cb *cb = NULL;
struct mei_device *dev;
int rets;
int err;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
if (length == 0) {
rets = 0;
goto out;
}
if (cl == &dev->iamthif_cl) {
rets = mei_amthif_read(dev, file, ubuf, length, offset);
goto out;
}
if (cl->read_cb) {
cb = cl->read_cb;
/* read what left */
if (cb->buf_idx > *offset)
goto copy_buffer;
/* offset is beyond buf_idx we have no more data return 0 */
if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
rets = 0;
goto free;
}
/* Offset needs to be cleaned for contiguous reads*/
if (cb->buf_idx == 0 && *offset > 0)
*offset = 0;
} else if (*offset > 0) {
*offset = 0;
}
err = mei_cl_read_start(cl, length);
if (err && err != -EBUSY) {
dev_dbg(&dev->pdev->dev,
"mei start read failure with status = %d\n", err);
rets = err;
goto out;
}
if (MEI_READ_COMPLETE != cl->reading_state &&
!waitqueue_active(&cl->rx_wait)) {
if (file->f_flags & O_NONBLOCK) {
rets = -EAGAIN;
goto out;
}
mutex_unlock(&dev->device_lock);
if (wait_event_interruptible(cl->rx_wait,
MEI_READ_COMPLETE == cl->reading_state ||
mei_cl_is_transitioning(cl))) {
if (signal_pending(current))
return -EINTR;
return -ERESTARTSYS;
}
mutex_lock(&dev->device_lock);
if (mei_cl_is_transitioning(cl)) {
rets = -EBUSY;
goto out;
}
}
cb = cl->read_cb;
if (!cb) {
rets = -ENODEV;
goto out;
}
if (cl->reading_state != MEI_READ_COMPLETE) {
rets = 0;
goto out;
}
/* now copy the data to user space */
copy_buffer:
dev_dbg(&dev->pdev->dev, "buf.size = %d buf.idx= %ld\n",
cb->response_buffer.size, cb->buf_idx);
if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) {
rets = -EMSGSIZE;
goto free;
}
/* length is being truncated to PAGE_SIZE,
* however buf_idx may point beyond that */
length = min_t(size_t, length, cb->buf_idx - *offset);
if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
rets = -EFAULT;
goto free;
}
rets = length;
*offset += length;
if ((unsigned long)*offset < cb->buf_idx)
goto out;
free:
cb_pos = mei_cl_find_read_cb(cl);
/* Remove entry from read list */
if (cb_pos)
list_del(&cb_pos->list);
mei_io_cb_free(cb);
cl->reading_state = MEI_IDLE;
cl->read_cb = NULL;
out:
dev_dbg(&dev->pdev->dev, "end mei read rets= %d\n", rets);
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_write - the write function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* Return: >=0 data length on success , <0 on error
*/
static ssize_t mei_write(struct file *file, const char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *cb;
struct mei_device *dev;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
if (!mei_cl_is_connected(cl)) {
cl_err(dev, cl, "is not connected");
rets = -ENODEV;
goto out;
}
if (!mei_me_cl_is_active(cl->me_cl)) {
rets = -ENOTTY;
goto out;
}
if (length > mei_cl_mtu(cl)) {
rets = -EFBIG;
goto out;
}
if (length == 0) {
rets = 0;
goto out;
}
*offset = 0;
cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file);
if (!cb) {
rets = -ENOMEM;
goto out;
}
rets = copy_from_user(cb->buf.data, ubuf, length);
if (rets) {
dev_dbg(dev->dev, "failed to copy data from userland\n");
rets = -EFAULT;
mei_io_cb_free(cb);
goto out;
}
if (cl == &dev->iamthif_cl) {
rets = mei_amthif_write(cl, cb);
if (!rets)
rets = length;
goto out;
}
rets = mei_cl_write(cl, cb);
out:
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_read - the read function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* Return: >=0 data length on success , <0 on error
*/
static ssize_t mei_read(struct file *file, char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_device *dev;
struct mei_cl_cb *cb = NULL;
bool nonblock = !!(file->f_flags & O_NONBLOCK);
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
if (length == 0) {
rets = 0;
goto out;
}
if (ubuf == NULL) {
rets = -EMSGSIZE;
goto out;
}
cb = mei_cl_read_cb(cl, file);
if (cb)
goto copy_buffer;
if (*offset > 0)
*offset = 0;
rets = mei_cl_read_start(cl, length, file);
if (rets && rets != -EBUSY) {
cl_dbg(dev, cl, "mei start read failure status = %d\n", rets);
goto out;
}
if (nonblock) {
rets = -EAGAIN;
goto out;
}
if (rets == -EBUSY &&
!mei_cl_enqueue_ctrl_wr_cb(cl, length, MEI_FOP_READ, file)) {
rets = -ENOMEM;
goto out;
}
do {
mutex_unlock(&dev->device_lock);
if (wait_event_interruptible(cl->rx_wait,
(!list_empty(&cl->rd_completed)) ||
(!mei_cl_is_connected(cl)))) {
if (signal_pending(current))
return -EINTR;
return -ERESTARTSYS;
}
mutex_lock(&dev->device_lock);
if (!mei_cl_is_connected(cl)) {
rets = -ENODEV;
goto out;
}
cb = mei_cl_read_cb(cl, file);
} while (!cb);
copy_buffer:
/* now copy the data to user space */
if (cb->status) {
rets = cb->status;
cl_dbg(dev, cl, "read operation failed %d\n", rets);
goto free;
}
cl_dbg(dev, cl, "buf.size = %zu buf.idx = %zu offset = %lld\n",
cb->buf.size, cb->buf_idx, *offset);
if (*offset >= cb->buf_idx) {
rets = 0;
goto free;
}
/* length is being truncated to PAGE_SIZE,
* however buf_idx may point beyond that */
length = min_t(size_t, length, cb->buf_idx - *offset);
if (copy_to_user(ubuf, cb->buf.data + *offset, length)) {
dev_dbg(dev->dev, "failed to copy data to userland\n");
rets = -EFAULT;
goto free;
}
rets = length;
*offset += length;
/* not all data was read, keep the cb */
if (*offset < cb->buf_idx)
goto out;
free:
mei_io_cb_free(cb);
*offset = 0;
out:
cl_dbg(dev, cl, "end mei read rets = %d\n", rets);
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_write - the write function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* Return: >=0 data length on success , <0 on error
*/
static ssize_t mei_write(struct file *file, const char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *cb;
struct mei_device *dev;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
if (!mei_cl_is_connected(cl)) {
cl_err(dev, cl, "is not connected");
rets = -ENODEV;
goto out;
}
if (!mei_me_cl_is_active(cl->me_cl)) {
rets = -ENOTTY;
goto out;
}
if (length > mei_cl_mtu(cl)) {
rets = -EFBIG;
goto out;
}
if (length == 0) {
rets = 0;
goto out;
}
while (cl->tx_cb_queued >= dev->tx_queue_limit) {
if (file->f_flags & O_NONBLOCK) {
rets = -EAGAIN;
goto out;
}
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);
if (rets) {
if (signal_pending(current))
rets = -EINTR;
goto out;
}
if (!mei_cl_is_connected(cl)) {
rets = -ENODEV;
goto out;
}
}
*offset = 0;
cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file);
if (!cb) {
rets = -ENOMEM;
goto out;
}
rets = copy_from_user(cb->buf.data, ubuf, length);
if (rets) {
dev_dbg(dev->dev, "failed to copy data from userland\n");
rets = -EFAULT;
mei_io_cb_free(cb);
goto out;
}
rets = mei_cl_write(cl, cb);
out:
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_read - the read function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* returns >=0 data length on success , <0 on error
*/
static ssize_t mei_read(struct file *file, char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *cb_pos = NULL;
struct mei_cl_cb *cb = NULL;
struct mei_device *dev;
int i;
int rets;
int err;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
if ((cl->sm_state & MEI_WD_STATE_INDEPENDENCE_MSG_SENT) == 0) {
/* Do not allow to read watchdog client */
i = mei_me_cl_by_uuid(dev, &mei_wd_guid);
if (i >= 0) {
struct mei_me_client *me_client = &dev->me_clients[i];
if (cl->me_client_id == me_client->client_id) {
rets = -EBADF;
goto out;
}
}
} else {
cl->sm_state &= ~MEI_WD_STATE_INDEPENDENCE_MSG_SENT;
}
if (cl == &dev->iamthif_cl) {
rets = mei_amthif_read(dev, file, ubuf, length, offset);
goto out;
}
if (cl->read_cb && cl->read_cb->buf_idx > *offset) {
cb = cl->read_cb;
goto copy_buffer;
} else if (cl->read_cb && cl->read_cb->buf_idx > 0 &&
cl->read_cb->buf_idx <= *offset) {
cb = cl->read_cb;
rets = 0;
goto free;
} else if ((!cl->read_cb || !cl->read_cb->buf_idx) && *offset > 0) {
/*Offset needs to be cleaned for contiguous reads*/
*offset = 0;
rets = 0;
goto out;
}
err = mei_cl_read_start(cl, length);
if (err && err != -EBUSY) {
dev_dbg(&dev->pdev->dev,
"mei start read failure with status = %d\n", err);
rets = err;
goto out;
}
if (MEI_READ_COMPLETE != cl->reading_state &&
!waitqueue_active(&cl->rx_wait)) {
if (file->f_flags & O_NONBLOCK) {
rets = -EAGAIN;
goto out;
}
mutex_unlock(&dev->device_lock);
if (wait_event_interruptible(cl->rx_wait,
(MEI_READ_COMPLETE == cl->reading_state ||
MEI_FILE_INITIALIZING == cl->state ||
MEI_FILE_DISCONNECTED == cl->state ||
MEI_FILE_DISCONNECTING == cl->state))) {
if (signal_pending(current))
return -EINTR;
return -ERESTARTSYS;
}
mutex_lock(&dev->device_lock);
if (MEI_FILE_INITIALIZING == cl->state ||
MEI_FILE_DISCONNECTED == cl->state ||
MEI_FILE_DISCONNECTING == cl->state) {
rets = -EBUSY;
goto out;
}
}
cb = cl->read_cb;
if (!cb) {
rets = -ENODEV;
goto out;
}
if (cl->reading_state != MEI_READ_COMPLETE) {
rets = 0;
goto out;
}
/* now copy the data to user space */
copy_buffer:
dev_dbg(&dev->pdev->dev, "buf.size = %d buf.idx= %ld\n",
cb->response_buffer.size, cb->buf_idx);
if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) {
rets = -EMSGSIZE;
goto free;
}
/* length is being truncated to PAGE_SIZE,
* however buf_idx may point beyond that */
length = min_t(size_t, length, cb->buf_idx - *offset);
if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
rets = -EFAULT;
goto free;
}
rets = length;
*offset += length;
if ((unsigned long)*offset < cb->buf_idx)
goto out;
free:
cb_pos = mei_cl_find_read_cb(cl);
/* Remove entry from read list */
if (cb_pos)
list_del(&cb_pos->list);
mei_io_cb_free(cb);
cl->reading_state = MEI_IDLE;
cl->read_cb = NULL;
out:
dev_dbg(&dev->pdev->dev, "end mei read rets= %d\n", rets);
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_amthif_read - read data from AMTHIF client
*
* @dev: the device structure
* @file: pointer to file object
* @ubuf: pointer to user data in user space
* @length: data length to read
* @offset: data read offset
*
* Locking: called under "dev->device_lock" lock
*
* Return:
* returned data length on success,
* zero if no data to read,
* negative on failure.
*/
int mei_amthif_read(struct mei_device *dev, struct file *file,
char __user *ubuf, size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *cb;
int rets;
int wait_ret;
dev_dbg(dev->dev, "checking amthif data\n");
cb = mei_cl_read_cb(cl, file);
/* Check for if we can block or not*/
if (cb == NULL && file->f_flags & O_NONBLOCK)
return -EAGAIN;
dev_dbg(dev->dev, "waiting for amthif data\n");
while (cb == NULL) {
/* unlock the Mutex */
mutex_unlock(&dev->device_lock);
wait_ret = wait_event_interruptible(cl->rx_wait,
!list_empty(&cl->rd_completed) ||
!mei_cl_is_connected(cl));
/* Locking again the Mutex */
mutex_lock(&dev->device_lock);
if (wait_ret)
return -ERESTARTSYS;
if (!mei_cl_is_connected(cl)) {
rets = -ENODEV;
goto out;
}
cb = mei_cl_read_cb(cl, file);
}
if (cb->status) {
rets = cb->status;
dev_dbg(dev->dev, "read operation failed %d\n", rets);
goto free;
}
dev_dbg(dev->dev, "Got amthif data\n");
/* if the whole message will fit remove it from the list */
if (cb->buf_idx >= *offset && length >= (cb->buf_idx - *offset))
list_del_init(&cb->list);
else if (cb->buf_idx <= *offset) {
/* end of the message has been reached */
list_del_init(&cb->list);
rets = 0;
goto free;
}
/* else means that not full buffer will be read and do not
* remove message from deletion list
*/
dev_dbg(dev->dev, "amthif cb->buf.size - %zu cb->buf_idx - %zu\n",
cb->buf.size, cb->buf_idx);
/* length is being truncated to PAGE_SIZE, however,
* the buf_idx may point beyond */
length = min_t(size_t, length, (cb->buf_idx - *offset));
if (copy_to_user(ubuf, cb->buf.data + *offset, length)) {
dev_dbg(dev->dev, "failed to copy data to userland\n");
rets = -EFAULT;
} else {
rets = length;
if ((*offset + length) < cb->buf_idx) {
*offset += length;
goto out;
}
}
free:
dev_dbg(dev->dev, "free amthif cb memory.\n");
*offset = 0;
mei_io_cb_free(cb);
out:
return rets;
}
/**
* mei_write - the write function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* Return: >=0 data length on success , <0 on error
*/
static ssize_t mei_write(struct file *file, const char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *write_cb = NULL;
struct mei_device *dev;
unsigned long timeout = 0;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
if (!mei_cl_is_connected(cl)) {
cl_err(dev, cl, "is not connected");
rets = -ENODEV;
goto out;
}
if (!mei_me_cl_is_active(cl->me_cl)) {
rets = -ENOTTY;
goto out;
}
if (length > mei_cl_mtu(cl)) {
rets = -EFBIG;
goto out;
}
if (length == 0) {
rets = 0;
goto out;
}
if (cl == &dev->iamthif_cl) {
write_cb = mei_amthif_find_read_list_entry(dev, file);
if (write_cb) {
timeout = write_cb->read_time +
mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
if (time_after(jiffies, timeout)) {
*offset = 0;
mei_io_cb_free(write_cb);
write_cb = NULL;
}
}
}
*offset = 0;
write_cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file);
if (!write_cb) {
rets = -ENOMEM;
goto out;
}
rets = copy_from_user(write_cb->buf.data, ubuf, length);
if (rets) {
dev_dbg(dev->dev, "failed to copy data from userland\n");
rets = -EFAULT;
goto out;
}
if (cl == &dev->iamthif_cl) {
rets = mei_amthif_write(cl, write_cb);
if (rets) {
dev_err(dev->dev,
"amthif write failed with status = %d\n", rets);
goto out;
}
mutex_unlock(&dev->device_lock);
return length;
}
rets = mei_cl_write(cl, write_cb, false);
out:
mutex_unlock(&dev->device_lock);
if (rets < 0)
mei_io_cb_free(write_cb);
return rets;
}
/**
* mei_read - the read function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* Return: >=0 data length on success , <0 on error
*/
static ssize_t mei_read(struct file *file, char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_device *dev;
struct mei_cl_cb *cb = NULL;
int rets;
int err;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
if (length == 0) {
rets = 0;
goto out;
}
if (cl == &dev->iamthif_cl) {
rets = mei_amthif_read(dev, file, ubuf, length, offset);
goto out;
}
cb = mei_cl_read_cb(cl, file);
if (cb) {
/* read what left */
if (cb->buf_idx > *offset)
goto copy_buffer;
/* offset is beyond buf_idx we have no more data return 0 */
if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
rets = 0;
goto free;
}
/* Offset needs to be cleaned for contiguous reads*/
if (cb->buf_idx == 0 && *offset > 0)
*offset = 0;
} else if (*offset > 0) {
*offset = 0;
}
err = mei_cl_read_start(cl, length, file);
if (err && err != -EBUSY) {
cl_dbg(dev, cl, "mei start read failure status = %d\n", err);
rets = err;
goto out;
}
if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) {
if (file->f_flags & O_NONBLOCK) {
rets = -EAGAIN;
goto out;
}
mutex_unlock(&dev->device_lock);
if (wait_event_interruptible(cl->rx_wait,
(!list_empty(&cl->rd_completed)) ||
(!mei_cl_is_connected(cl)))) {
if (signal_pending(current))
return -EINTR;
return -ERESTARTSYS;
}
mutex_lock(&dev->device_lock);
if (!mei_cl_is_connected(cl)) {
rets = -EBUSY;
goto out;
}
}
cb = mei_cl_read_cb(cl, file);
if (!cb) {
if (mei_cl_is_fixed_address(cl) && dev->allow_fixed_address) {
cb = mei_cl_read_cb(cl, NULL);
if (cb)
goto copy_buffer;
}
rets = 0;
goto out;
}
copy_buffer:
/* now copy the data to user space */
if (cb->status) {
rets = cb->status;
cl_dbg(dev, cl, "read operation failed %d\n", rets);
goto free;
}
cl_dbg(dev, cl, "buf.size = %d buf.idx = %ld\n",
cb->buf.size, cb->buf_idx);
if (length == 0 || ubuf == NULL || *offset > cb->buf_idx) {
rets = -EMSGSIZE;
goto free;
}
/* length is being truncated to PAGE_SIZE,
* however buf_idx may point beyond that */
length = min_t(size_t, length, cb->buf_idx - *offset);
if (copy_to_user(ubuf, cb->buf.data + *offset, length)) {
dev_dbg(dev->dev, "failed to copy data to userland\n");
rets = -EFAULT;
goto free;
}
rets = length;
*offset += length;
if ((unsigned long)*offset < cb->buf_idx)
goto out;
free:
mei_io_cb_free(cb);
out:
cl_dbg(dev, cl, "end mei read rets = %d\n", rets);
mutex_unlock(&dev->device_lock);
return rets;
}
