diff options
Diffstat (limited to 'drivers/char/tpm/tpm-dev-common.c')
| -rw-r--r-- | drivers/char/tpm/tpm-dev-common.c | 52 |
1 files changed, 36 insertions, 16 deletions
diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c index 99b5133a9d05..5eecad233ea1 100644 --- a/drivers/char/tpm/tpm-dev-common.c +++ b/drivers/char/tpm/tpm-dev-common.c @@ -40,7 +40,7 @@ static void tpm_async_work(struct work_struct *work) tpm_put_ops(priv->chip); if (ret > 0) { - priv->data_pending = ret; + priv->response_length = ret; mod_timer(&priv->user_read_timer, jiffies + (120 * HZ)); } mutex_unlock(&priv->buffer_mutex); @@ -63,7 +63,8 @@ static void tpm_timeout_work(struct work_struct *work) timeout_work); mutex_lock(&priv->buffer_mutex); - priv->data_pending = 0; + priv->response_read = true; + priv->response_length = 0; memset(priv->data_buffer, 0, sizeof(priv->data_buffer)); mutex_unlock(&priv->buffer_mutex); wake_up_interruptible(&priv->async_wait); @@ -74,6 +75,7 @@ void tpm_common_open(struct file *file, struct tpm_chip *chip, { priv->chip = chip; priv->space = space; + priv->response_read = true; mutex_init(&priv->buffer_mutex); timer_setup(&priv->user_read_timer, user_reader_timeout, 0); @@ -90,22 +92,35 @@ ssize_t tpm_common_read(struct file *file, char __user *buf, ssize_t ret_size = 0; int rc; - del_singleshot_timer_sync(&priv->user_read_timer); - flush_work(&priv->timeout_work); mutex_lock(&priv->buffer_mutex); - if (priv->data_pending) { - ret_size = min_t(ssize_t, size, priv->data_pending); - if (ret_size > 0) { - rc = copy_to_user(buf, priv->data_buffer, ret_size); - memset(priv->data_buffer, 0, priv->data_pending); - if (rc) - ret_size = -EFAULT; + if (priv->response_length) { + priv->response_read = true; + + ret_size = min_t(ssize_t, size, priv->response_length); + if (!ret_size) { + priv->response_length = 0; + goto out; } - priv->data_pending = 0; + rc = copy_to_user(buf, priv->data_buffer + *off, ret_size); + if (rc) { + memset(priv->data_buffer, 0, TPM_BUFSIZE); + priv->response_length = 0; + ret_size = -EFAULT; + } else { + memset(priv->data_buffer + *off, 0, ret_size); + priv->response_length -= ret_size; + *off += ret_size; + } } +out: + if (!priv->response_length) { + *off = 0; + del_singleshot_timer_sync(&priv->user_read_timer); + flush_work(&priv->timeout_work); + } mutex_unlock(&priv->buffer_mutex); return ret_size; } @@ -125,7 +140,8 @@ ssize_t tpm_common_write(struct file *file, const char __user *buf, * tpm_read or a user_read_timer timeout. This also prevents split * buffered writes from blocking here. */ - if (priv->data_pending != 0 || priv->command_enqueued) { + if ((!priv->response_read && priv->response_length) || + priv->command_enqueued) { ret = -EBUSY; goto out; } @@ -150,6 +166,10 @@ ssize_t tpm_common_write(struct file *file, const char __user *buf, goto out; } + priv->response_length = 0; + priv->response_read = false; + *off = 0; + /* * If in nonblocking mode schedule an async job to send * the command return the size. @@ -168,7 +188,7 @@ ssize_t tpm_common_write(struct file *file, const char __user *buf, tpm_put_ops(priv->chip); if (ret > 0) { - priv->data_pending = ret; + priv->response_length = ret; mod_timer(&priv->user_read_timer, jiffies + (120 * HZ)); ret = size; } @@ -184,7 +204,7 @@ __poll_t tpm_common_poll(struct file *file, poll_table *wait) poll_wait(file, &priv->async_wait, wait); - if (priv->data_pending) + if (!priv->response_read || priv->response_length) mask = EPOLLIN | EPOLLRDNORM; else mask = EPOLLOUT | EPOLLWRNORM; @@ -201,7 +221,7 @@ void tpm_common_release(struct file *file, struct file_priv *priv) del_singleshot_timer_sync(&priv->user_read_timer); flush_work(&priv->timeout_work); file->private_data = NULL; - priv->data_pending = 0; + priv->response_length = 0; } int __init tpm_dev_common_init(void) |