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 <[email protected]>
---
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;
+
+ 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;
}
--
2.17.1
On Mon, 1 Feb 2021 16:50:59 +0200
Alexandru Ardelean <[email protected]> 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 <[email protected]>
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
<[email protected]> wrote:
>
> On Mon, 1 Feb 2021 16:50:59 +0200
> Alexandru Ardelean <[email protected]> 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 <[email protected]>
> 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