On Wed, Mar 18, 2015 at 11:29 AM, Octavian Purdila <octavian.purdila@xxxxxxxxx> wrote: > On Wed, Mar 18, 2015 at 11:19 AM, Lars-Peter Clausen <lars@xxxxxxxxxx> wrote: >> Looks good mostly, two things. >> > > Thanks for the review Lars ! > >> On 03/04/2015 06:56 PM, Octavian Purdila wrote: >> [...] >>> >>> @@ -61,19 +80,24 @@ ssize_t iio_buffer_read_first_n_outer(struct file >>> *filp, char __user *buf, >>> if (!rb || !rb->access->read_first_n) >>> return -EINVAL; >>> >>> + /* >>> + * If datum_size is 0 there will never be anything to read from >>> the >>> + * buffer, so signal end of file now. >>> + */ >>> + if (!datum_size) >>> + return 0; >>> + >>> + if (!(filp->f_flags & O_NONBLOCK)) >>> + to_wait = min_t(size_t, n / datum_size, rb->watermark); >>> + >>> do { >>> - if (!iio_buffer_data_available(rb)) { >>> - if (filp->f_flags & O_NONBLOCK) >>> - return -EAGAIN; >> >> >> If I understand this correctly we no longer return -EAGAIN if no data is >> available in non blocking mode, but rather return 0. Which means >> end-of-file, so it is not correct. >> > > You are right, I'll add have to add back the if > (!iio_buffer_data_available(rb) && (filp->f_flags & O_NONBLOCK)) > statement. > >>> + ret = wait_event_interruptible(rb->pollq, >>> + iio_buffer_ready(indio_dev, rb, >>> to_wait)); >>> + if (ret) >>> + return ret; >>> >>> - ret = wait_event_interruptible(rb->pollq, >>> - iio_buffer_data_available(rb) || >>> - indio_dev->info == NULL); >>> - if (ret) >>> - return ret; >>> - if (indio_dev->info == NULL) >>> - return -ENODEV; >>> - } >>> + if (!indio_dev->info) >>> + return -ENODEV; >>> [...] >>> + >>> +static ssize_t iio_buffer_store_watermark(struct device *dev, >>> + struct device_attribute *attr, >>> + const char *buf, >>> + size_t len) >>> +{ >>> + struct iio_dev *indio_dev = dev_to_iio_dev(dev); >>> + struct iio_buffer *buffer = indio_dev->buffer; >>> + unsigned int val; >>> + int ret; >>> + >>> + ret = kstrtouint(buf, 10, &val); >>> + if (ret) >>> + return ret; >>> + if (!val) >>> + return -EINVAL; >>> + >>> + mutex_lock(&indio_dev->mlock); >>> + >>> + if (val > buffer->length) { >>> + ret = -EINVAL; >>> + goto out; >>> + } >> >> >> This is missing the check for val == 0. >> > > Unless I misunderstand you, the check is done right after kstrtouint() > before taking the lock. > >> >>> + >>> + if (iio_buffer_is_active(indio_dev->buffer)) { >>> + ret = -EBUSY; >>> + goto out; >>> + } >>> + >>> + buffer->watermark = val; >>> +out: >>> + mutex_unlock(&indio_dev->mlock); >>> + >>> + return ret ? ret : len; >>> +} >> >> -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html