Re: [PATCH 1/9] HSI: cmt_speech: Add cmt-speech driver

From: Oliver Neukum
Date: Mon Mar 02 2015 - 05:30:10 EST



> +static ssize_t cs_char_read(struct file *file, char __user *buf, size_t count,
> + loff_t *unused)
> +{
> + struct cs_char *csdata = file->private_data;
> + u32 data;
> + ssize_t retval;
> +
> + if (count < sizeof(data))
> + return -EINVAL;
> +
> + for ( ; ; ) {
> + DEFINE_WAIT(wait);
> +
> + spin_lock_bh(&csdata->lock);
> + if (!list_empty(&csdata->chardev_queue)) {
> + data = cs_pop_entry(&csdata->chardev_queue);
> + } else if (!list_empty(&csdata->dataind_queue)) {
> + data = cs_pop_entry(&csdata->dataind_queue);
> + --csdata->dataind_pending;
> +
> + } else {
> + data = 0;
> + }
> + spin_unlock_bh(&csdata->lock);
> +
> + if (data)
> + break;
> + if (file->f_flags & O_NONBLOCK) {
> + retval = -EAGAIN;
> + goto out;
> + } else if (signal_pending(current)) {
> + retval = -ERESTARTSYS;
> + goto out;
> + }
> + prepare_to_wait_exclusive(&csdata->wait, &wait,
> + TASK_INTERRUPTIBLE);
> + schedule();
> + finish_wait(&csdata->wait, &wait);
> + }
> +
> + retval = put_user(data, (u32 __user *)buf);
> + if (!retval)
> + retval = sizeof(data);
> +
> +out:
> + return retval;
> +}
> +
> +static ssize_t cs_char_write(struct file *file, const char __user *buf,
> + size_t count, loff_t *unused)
> +{
> + struct cs_char *csdata = file->private_data;
> + u32 data;
> + int err;
> + ssize_t retval;
> +
> + if (count < sizeof(data))
> + return -EINVAL;
> +
> + if (get_user(data, (u32 __user *)buf))
> + retval = -EFAULT;
> + else
> + retval = count;

You want to execute the command even if you got -EFAULT?
That is highly unusual.

> +
> + err = cs_hsi_command(csdata->hi, data);
> + if (err < 0)
> + retval = err;
> +
> + return retval;
> +}
> +
> +static long cs_char_ioctl(struct file *file, unsigned int cmd,
> + unsigned long arg)
> +{
> + struct cs_char *csdata = file->private_data;
> + int r = 0;
> +
> + switch (cmd) {
> + case CS_GET_STATE: {
> + unsigned int state;
> +
> + state = cs_hsi_get_state(csdata->hi);
> + if (copy_to_user((void __user *)arg, &state, sizeof(state)))
> + r = -EFAULT;
> + }
> + break;
> + case CS_SET_WAKELINE: {
> + unsigned int state;
> +
> + if (copy_from_user(&state, (void __user *)arg, sizeof(state)))
> + r = -EFAULT;
> + else
> + cs_hsi_set_wakeline(csdata->hi, state);

No sanity checking for state?

> + }
> + break;
> + case CS_GET_IF_VERSION: {
> + unsigned int ifver = CS_IF_VERSION;
> +
> + if (copy_to_user((void __user *)arg, &ifver, sizeof(ifver)))
> + r = -EFAULT;
> + break;
> + }
> + case CS_CONFIG_BUFS: {
> + struct cs_buffer_config buf_cfg;
> +
> + if (copy_from_user(&buf_cfg, (void __user *)arg,
> + sizeof(buf_cfg)))
> + r = -EFAULT;
> + else
> + r = cs_hsi_buf_config(csdata->hi, &buf_cfg);

Sanity checking?

> + break;
> + }
> + default:
> + r = -ENOTTY;
> + break;
> + }
> +
> + return r;
> +}
> +
> +static int cs_char_mmap(struct file *file, struct vm_area_struct *vma)
> +{
> + if (vma->vm_end < vma->vm_start)
> + return -EINVAL;
> +
> + if (((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) != 1)
> + return -EINVAL;
> +
> + vma->vm_flags |= VM_RESERVED;
> + vma->vm_ops = &cs_char_vm_ops;
> + vma->vm_private_data = file->private_data;
> +
> + return 0;
> +}
> +
> +static int cs_char_open(struct inode *unused, struct file *file)
> +{
> + int ret = 0;
> +
> + spin_lock_bh(&cs_char_data.lock);
> + if (cs_char_data.opened) {
> + ret = -EBUSY;
> + spin_unlock_bh(&cs_char_data.lock);
> + goto out;
> + }
> + cs_char_data.mmap_base = get_zeroed_page(GFP_ATOMIC);

This could be moved outside the locked sectionand use GFP_KERNEL.

> + if (!cs_char_data.mmap_base) {
> + dev_err(&cs_char_data.cl->device,
> + "Shared memory allocation failed.\n");
> + ret = -ENOMEM;
> + spin_unlock_bh(&cs_char_data.lock);
> + goto out;
> + }
> + cs_char_data.mmap_size = CS_MMAP_SIZE;
> + cs_char_data.dataind_pending = 0;
> + cs_char_data.opened = 1;
> + file->private_data = &cs_char_data;
> + spin_unlock_bh(&cs_char_data.lock);
> +
> + BUG_ON(cs_char_data.hi);
> +
> + ret = cs_hsi_start(&cs_char_data.hi, cs_char_data.cl,
> + cs_char_data.mmap_base, cs_char_data.mmap_size);
> + if (ret) {
> + dev_err(&cs_char_data.cl->device, "Unable to initialize HSI\n");
> + free_page(cs_char_data.mmap_base);
> + goto out;
> + }
> +
> +out:
> + return ret;
> +}


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