| Message ID | 20210201145105.20459-6-alexandru.ardelean@analog.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: core,buffer: add support for multiple IIO buffers per IIO device | expand |
On Mon, 1 Feb 2021 16:50:59 +0200 Alexandru Ardelean <alexandru.ardelean@analog.com> wrote: > If we want to merge the attributes of the buffer/ and scan_elements/ > directories, we'll need to count all attributes first, then (depending on > the attribute group) either allocate 2 attribute groups, or a single one. Probably want to note why we might want to do 2 or 1 group here as it sounds weird without knowing where this is going. > > This change moves the allocation of the buffer/ attributes closer to the > allocation of the scan_elements/ attributes to make grouping easier. > > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> This is fine, but one comment on a possible tidy up for another day inline. Jonathan > --- > drivers/iio/industrialio-buffer.c | 71 ++++++++++++++++--------------- > 1 file changed, 37 insertions(+), 34 deletions(-) > > diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c > index cc846988fdb9..23f22be62cc7 100644 > --- a/drivers/iio/industrialio-buffer.c > +++ b/drivers/iio/industrialio-buffer.c > @@ -1257,41 +1257,16 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, > { > struct iio_dev_attr *p; > struct attribute **attr; > - int ret, i, attrn, attrcount; > + int ret, i, attrn, scan_el_attrcount, buffer_attrcount; > const struct iio_chan_spec *channels; > > - attrcount = 0; > + buffer_attrcount = 0; > if (buffer->attrs) { > - while (buffer->attrs[attrcount] != NULL) > - attrcount++; > + while (buffer->attrs[buffer_attrcount] != NULL) > + buffer_attrcount++; > } > > - attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, > - sizeof(struct attribute *), GFP_KERNEL); > - if (!attr) > - return -ENOMEM; > - > - memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); > - if (!buffer->access->set_length) > - attr[0] = &dev_attr_length_ro.attr; > - > - if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) > - attr[2] = &dev_attr_watermark_ro.attr; > - > - if (buffer->attrs) > - memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, > - sizeof(struct attribute *) * attrcount); > - > - attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL; > - > - buffer->buffer_group.name = "buffer"; > - buffer->buffer_group.attrs = attr; > - > - ret = iio_device_register_sysfs_group(indio_dev, &buffer->buffer_group); > - if (ret) > - goto error_free_buffer_attrs; > - > - attrcount = 0; > + scan_el_attrcount = 0; > INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); > channels = indio_dev->channels; > if (channels) { > @@ -1304,7 +1279,7 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, > &channels[i]); > if (ret < 0) > goto error_cleanup_dynamic; > - attrcount += ret; > + scan_el_attrcount += ret; > if (channels[i].type == IIO_TIMESTAMP) > indio_dev->scan_index_timestamp = > channels[i].scan_index; > @@ -1319,9 +1294,37 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, > } > } > > + attr = kcalloc(buffer_attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, > + sizeof(struct attribute *), GFP_KERNEL); > + if (!attr) { > + ret = -ENOMEM; > + goto error_free_scan_mask; > + } > + > + memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); > + if (!buffer->access->set_length) > + attr[0] = &dev_attr_length_ro.attr; > + > + if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) > + attr[2] = &dev_attr_watermark_ro.attr; Again a comment for the future rather than now, but when we are copying 4 items and then looking at whether to change 2 of them it might be cleaner to just set them directly! Touch of bit rot here :) > + > + if (buffer->attrs) > + memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, > + sizeof(struct attribute *) * buffer_attrcount); > + > + buffer_attrcount += ARRAY_SIZE(iio_buffer_attrs); > + attr[buffer_attrcount] = NULL; > + > + buffer->buffer_group.name = "buffer"; > + buffer->buffer_group.attrs = attr; > + > + ret = iio_device_register_sysfs_group(indio_dev, &buffer->buffer_group); > + if (ret) > + goto error_free_buffer_attrs; > + > buffer->scan_el_group.name = iio_scan_elements_group_name; > > - buffer->scan_el_group.attrs = kcalloc(attrcount + 1, > + buffer->scan_el_group.attrs = kcalloc(scan_el_attrcount + 1, > sizeof(buffer->scan_el_group.attrs[0]), > GFP_KERNEL); > if (buffer->scan_el_group.attrs == NULL) { > @@ -1341,12 +1344,12 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, > > error_free_scan_el_attrs: > kfree(buffer->scan_el_group.attrs); > +error_free_buffer_attrs: > + kfree(buffer->buffer_group.attrs); > error_free_scan_mask: > bitmap_free(buffer->scan_mask); > error_cleanup_dynamic: > iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); > -error_free_buffer_attrs: > - kfree(buffer->buffer_group.attrs); > > return ret; > }
On Thu, Feb 4, 2021 at 7:57 PM Jonathan Cameron <Jonathan.Cameron@huawei.com> wrote: > > On Mon, 1 Feb 2021 16:50:59 +0200 > Alexandru Ardelean <alexandru.ardelean@analog.com> wrote: > > > If we want to merge the attributes of the buffer/ and scan_elements/ > > directories, we'll need to count all attributes first, then (depending on > > the attribute group) either allocate 2 attribute groups, or a single one. > > Probably want to note why we might want to do 2 or 1 group here as it > sounds weird without knowing where this is going. ack > > > > > This change moves the allocation of the buffer/ attributes closer to the > > allocation of the scan_elements/ attributes to make grouping easier. > > > > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> > This is fine, but one comment on a possible tidy up for another day inline. > > Jonathan > > > --- > > drivers/iio/industrialio-buffer.c | 71 ++++++++++++++++--------------- > > 1 file changed, 37 insertions(+), 34 deletions(-) > > > > diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c > > index cc846988fdb9..23f22be62cc7 100644 > > --- a/drivers/iio/industrialio-buffer.c > > +++ b/drivers/iio/industrialio-buffer.c > > @@ -1257,41 +1257,16 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, > > { > > struct iio_dev_attr *p; > > struct attribute **attr; > > - int ret, i, attrn, attrcount; > > + int ret, i, attrn, scan_el_attrcount, buffer_attrcount; > > const struct iio_chan_spec *channels; > > > > - attrcount = 0; > > + buffer_attrcount = 0; > > if (buffer->attrs) { > > - while (buffer->attrs[attrcount] != NULL) > > - attrcount++; > > + while (buffer->attrs[buffer_attrcount] != NULL) > > + buffer_attrcount++; > > } > > > > - attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, > > - sizeof(struct attribute *), GFP_KERNEL); > > - if (!attr) > > - return -ENOMEM; > > - > > - memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); > > - if (!buffer->access->set_length) > > - attr[0] = &dev_attr_length_ro.attr; > > - > > - if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) > > - attr[2] = &dev_attr_watermark_ro.attr; > > - > > - if (buffer->attrs) > > - memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, > > - sizeof(struct attribute *) * attrcount); > > - > > - attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL; > > - > > - buffer->buffer_group.name = "buffer"; > > - buffer->buffer_group.attrs = attr; > > - > > - ret = iio_device_register_sysfs_group(indio_dev, &buffer->buffer_group); > > - if (ret) > > - goto error_free_buffer_attrs; > > - > > - attrcount = 0; > > + scan_el_attrcount = 0; > > INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); > > channels = indio_dev->channels; > > if (channels) { > > @@ -1304,7 +1279,7 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, > > &channels[i]); > > if (ret < 0) > > goto error_cleanup_dynamic; > > - attrcount += ret; > > + scan_el_attrcount += ret; > > if (channels[i].type == IIO_TIMESTAMP) > > indio_dev->scan_index_timestamp = > > channels[i].scan_index; > > @@ -1319,9 +1294,37 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, > > } > > } > > > > + attr = kcalloc(buffer_attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, > > + sizeof(struct attribute *), GFP_KERNEL); > > + if (!attr) { > > + ret = -ENOMEM; > > + goto error_free_scan_mask; > > + } > > + > > + memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); > > + if (!buffer->access->set_length) > > + attr[0] = &dev_attr_length_ro.attr; > > + > > + if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) > > + attr[2] = &dev_attr_watermark_ro.attr; > > Again a comment for the future rather than now, but when we are copying > 4 items and then looking at whether to change 2 of them it might be cleaner > to just set them directly! Touch of bit rot here :) So, I've been on-and-off about how to deal with this one. I wanted to clean it in various ways using new kernel sysfs APIs. Maybe, also remove the readonly variants and use the is_visible() property to set RO/RW modes. But I also came to the conclusion that this is an idea to address later. Trying to address this early-on confused me with other overlapping changes. > > > + > > + if (buffer->attrs) > > + memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, > > + sizeof(struct attribute *) * buffer_attrcount); > > + > > + buffer_attrcount += ARRAY_SIZE(iio_buffer_attrs); > > + attr[buffer_attrcount] = NULL; > > + > > + buffer->buffer_group.name = "buffer"; > > + buffer->buffer_group.attrs = attr; > > + > > + ret = iio_device_register_sysfs_group(indio_dev, &buffer->buffer_group); > > + if (ret) > > + goto error_free_buffer_attrs; > > + > > buffer->scan_el_group.name = iio_scan_elements_group_name; > > > > - buffer->scan_el_group.attrs = kcalloc(attrcount + 1, > > + buffer->scan_el_group.attrs = kcalloc(scan_el_attrcount + 1, > > sizeof(buffer->scan_el_group.attrs[0]), > > GFP_KERNEL); > > if (buffer->scan_el_group.attrs == NULL) { > > @@ -1341,12 +1344,12 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, > > > > error_free_scan_el_attrs: > > kfree(buffer->scan_el_group.attrs); > > +error_free_buffer_attrs: > > + kfree(buffer->buffer_group.attrs); > > error_free_scan_mask: > > bitmap_free(buffer->scan_mask); > > error_cleanup_dynamic: > > iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); > > -error_free_buffer_attrs: > > - kfree(buffer->buffer_group.attrs); > > > > return ret; > > } >
> > > > > > + attr = kcalloc(buffer_attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, > > > + sizeof(struct attribute *), GFP_KERNEL); > > > + if (!attr) { > > > + ret = -ENOMEM; > > > + goto error_free_scan_mask; > > > + } > > > + > > > + memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); > > > + if (!buffer->access->set_length) > > > + attr[0] = &dev_attr_length_ro.attr; > > > + > > > + if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) > > > + attr[2] = &dev_attr_watermark_ro.attr; > > > > Again a comment for the future rather than now, but when we are copying > > 4 items and then looking at whether to change 2 of them it might be cleaner > > to just set them directly! Touch of bit rot here :) > > So, I've been on-and-off about how to deal with this one. > I wanted to clean it in various ways using new kernel sysfs APIs. > Maybe, also remove the readonly variants and use the is_visible() > property to set RO/RW modes. > But I also came to the conclusion that this is an idea to address later. > Trying to address this early-on confused me with other overlapping changes. Absolutely agree. It's not something to do in this series. Jonathan
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c index cc846988fdb9..23f22be62cc7 100644 --- a/drivers/iio/industrialio-buffer.c +++ b/drivers/iio/industrialio-buffer.c @@ -1257,41 +1257,16 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, { struct iio_dev_attr *p; struct attribute **attr; - int ret, i, attrn, attrcount; + int ret, i, attrn, scan_el_attrcount, buffer_attrcount; const struct iio_chan_spec *channels; - attrcount = 0; + buffer_attrcount = 0; if (buffer->attrs) { - while (buffer->attrs[attrcount] != NULL) - attrcount++; + while (buffer->attrs[buffer_attrcount] != NULL) + buffer_attrcount++; } - attr = kcalloc(attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, - sizeof(struct attribute *), GFP_KERNEL); - if (!attr) - return -ENOMEM; - - memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); - if (!buffer->access->set_length) - attr[0] = &dev_attr_length_ro.attr; - - if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) - attr[2] = &dev_attr_watermark_ro.attr; - - if (buffer->attrs) - memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, - sizeof(struct attribute *) * attrcount); - - attr[attrcount + ARRAY_SIZE(iio_buffer_attrs)] = NULL; - - buffer->buffer_group.name = "buffer"; - buffer->buffer_group.attrs = attr; - - ret = iio_device_register_sysfs_group(indio_dev, &buffer->buffer_group); - if (ret) - goto error_free_buffer_attrs; - - attrcount = 0; + scan_el_attrcount = 0; INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list); channels = indio_dev->channels; if (channels) { @@ -1304,7 +1279,7 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, &channels[i]); if (ret < 0) goto error_cleanup_dynamic; - attrcount += ret; + scan_el_attrcount += ret; if (channels[i].type == IIO_TIMESTAMP) indio_dev->scan_index_timestamp = channels[i].scan_index; @@ -1319,9 +1294,37 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, } } + attr = kcalloc(buffer_attrcount + ARRAY_SIZE(iio_buffer_attrs) + 1, + sizeof(struct attribute *), GFP_KERNEL); + if (!attr) { + ret = -ENOMEM; + goto error_free_scan_mask; + } + + memcpy(attr, iio_buffer_attrs, sizeof(iio_buffer_attrs)); + if (!buffer->access->set_length) + attr[0] = &dev_attr_length_ro.attr; + + if (buffer->access->flags & INDIO_BUFFER_FLAG_FIXED_WATERMARK) + attr[2] = &dev_attr_watermark_ro.attr; + + if (buffer->attrs) + memcpy(&attr[ARRAY_SIZE(iio_buffer_attrs)], buffer->attrs, + sizeof(struct attribute *) * buffer_attrcount); + + buffer_attrcount += ARRAY_SIZE(iio_buffer_attrs); + attr[buffer_attrcount] = NULL; + + buffer->buffer_group.name = "buffer"; + buffer->buffer_group.attrs = attr; + + ret = iio_device_register_sysfs_group(indio_dev, &buffer->buffer_group); + if (ret) + goto error_free_buffer_attrs; + buffer->scan_el_group.name = iio_scan_elements_group_name; - buffer->scan_el_group.attrs = kcalloc(attrcount + 1, + buffer->scan_el_group.attrs = kcalloc(scan_el_attrcount + 1, sizeof(buffer->scan_el_group.attrs[0]), GFP_KERNEL); if (buffer->scan_el_group.attrs == NULL) { @@ -1341,12 +1344,12 @@ static int __iio_buffer_alloc_sysfs_and_mask(struct iio_buffer *buffer, error_free_scan_el_attrs: kfree(buffer->scan_el_group.attrs); +error_free_buffer_attrs: + kfree(buffer->buffer_group.attrs); error_free_scan_mask: bitmap_free(buffer->scan_mask); error_cleanup_dynamic: iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list); -error_free_buffer_attrs: - kfree(buffer->buffer_group.attrs); return ret; }
If we want to merge the attributes of the buffer/ and scan_elements/ directories, we'll need to count all attributes first, then (depending on the attribute group) either allocate 2 attribute groups, or a single one. This change moves the allocation of the buffer/ attributes closer to the allocation of the scan_elements/ attributes to make grouping easier. Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com> --- drivers/iio/industrialio-buffer.c | 71 ++++++++++++++++--------------- 1 file changed, 37 insertions(+), 34 deletions(-)