On Mon, Apr 26, 2021 at 8:50 PM Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
>
> From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
>
> This lock is only of interest to the IIO core, so make it only
> visible there.
This was on my list at some point, but I deferred it because it was
overlapping with the IIO buffer stuff.
Reviewed-by: Alexandru Ardelean <ardeleanalex@xxxxxxxxx>
>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> ---
> drivers/iio/industrialio-buffer.c | 5 ++--
> drivers/iio/industrialio-core.c | 10 +++----
> drivers/iio/inkern.c | 46 +++++++++++++++++++------------
> include/linux/iio/iio-opaque.h | 2 ++
> include/linux/iio/iio.h | 2 --
> 5 files changed, 38 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
> index 9ecb3c58d94c..10923b40c76d 100644
> --- a/drivers/iio/industrialio-buffer.c
> +++ b/drivers/iio/industrialio-buffer.c
> @@ -1150,12 +1150,13 @@ int iio_update_buffers(struct iio_dev *indio_dev,
> struct iio_buffer *insert_buffer,
> struct iio_buffer *remove_buffer)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
> int ret;
>
> if (insert_buffer == remove_buffer)
> return 0;
>
> - mutex_lock(&indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> mutex_lock(&indio_dev->mlock);
>
> if (insert_buffer && iio_buffer_is_active(insert_buffer))
> @@ -1178,7 +1179,7 @@ int iio_update_buffers(struct iio_dev *indio_dev,
>
> out_unlock:
> mutex_unlock(&indio_dev->mlock);
> - mutex_unlock(&indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index 8c38f1f6e075..f3b38d69b7e1 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -1642,7 +1642,7 @@ struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv)
> device_initialize(&indio_dev->dev);
> iio_device_set_drvdata(indio_dev, (void *)indio_dev);
> mutex_init(&indio_dev->mlock);
> - mutex_init(&indio_dev->info_exist_lock);
> + mutex_init(&iio_dev_opaque->info_exist_lock);
> INIT_LIST_HEAD(&iio_dev_opaque->channel_attr_list);
>
> iio_dev_opaque->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL);
> @@ -1779,7 +1779,7 @@ static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> struct iio_ioctl_handler *h;
> int ret = -ENODEV;
>
> - mutex_lock(&indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
>
> /**
> * The NULL check here is required to prevent crashing when a device
> @@ -1800,7 +1800,7 @@ static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> ret = -EINVAL;
>
> out_unlock:
> - mutex_unlock(&indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> @@ -1942,7 +1942,7 @@ void iio_device_unregister(struct iio_dev *indio_dev)
>
> cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);
>
> - mutex_lock(&indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
>
> iio_device_unregister_debugfs(indio_dev);
>
> @@ -1956,7 +1956,7 @@ void iio_device_unregister(struct iio_dev *indio_dev)
> iio_device_wakeup_eventset(indio_dev);
> iio_buffer_wakeup_poll(indio_dev);
>
> - mutex_unlock(&indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> iio_buffers_free_sysfs_and_mask(indio_dev);
> }
> diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
> index 5aa740cea661..391a3380a1d1 100644
> --- a/drivers/iio/inkern.c
> +++ b/drivers/iio/inkern.c
> @@ -10,6 +10,7 @@
> #include <linux/of.h>
>
> #include <linux/iio/iio.h>
> +#include <linux/iio/iio-opaque.h>
> #include "iio_core.h"
> #include <linux/iio/machine.h>
> #include <linux/iio/driver.h>
> @@ -538,9 +539,10 @@ static int iio_channel_read(struct iio_channel *chan, int *val, int *val2,
>
> int iio_read_channel_raw(struct iio_channel *chan, int *val)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
> int ret;
>
> - mutex_lock(&chan->indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> if (chan->indio_dev->info == NULL) {
> ret = -ENODEV;
> goto err_unlock;
> @@ -548,7 +550,7 @@ int iio_read_channel_raw(struct iio_channel *chan, int *val)
>
> ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_RAW);
> err_unlock:
> - mutex_unlock(&chan->indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> @@ -556,9 +558,10 @@ EXPORT_SYMBOL_GPL(iio_read_channel_raw);
>
> int iio_read_channel_average_raw(struct iio_channel *chan, int *val)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
> int ret;
>
> - mutex_lock(&chan->indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> if (chan->indio_dev->info == NULL) {
> ret = -ENODEV;
> goto err_unlock;
> @@ -566,7 +569,7 @@ int iio_read_channel_average_raw(struct iio_channel *chan, int *val)
>
> ret = iio_channel_read(chan, val, NULL, IIO_CHAN_INFO_AVERAGE_RAW);
> err_unlock:
> - mutex_unlock(&chan->indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> @@ -631,9 +634,10 @@ static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
> int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
> int *processed, unsigned int scale)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
> int ret;
>
> - mutex_lock(&chan->indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> if (chan->indio_dev->info == NULL) {
> ret = -ENODEV;
> goto err_unlock;
> @@ -642,7 +646,7 @@ int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
> ret = iio_convert_raw_to_processed_unlocked(chan, raw, processed,
> scale);
> err_unlock:
> - mutex_unlock(&chan->indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> @@ -651,9 +655,10 @@ EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed);
> int iio_read_channel_attribute(struct iio_channel *chan, int *val, int *val2,
> enum iio_chan_info_enum attribute)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
> int ret;
>
> - mutex_lock(&chan->indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> if (chan->indio_dev->info == NULL) {
> ret = -ENODEV;
> goto err_unlock;
> @@ -661,7 +666,7 @@ int iio_read_channel_attribute(struct iio_channel *chan, int *val, int *val2,
>
> ret = iio_channel_read(chan, val, val2, attribute);
> err_unlock:
> - mutex_unlock(&chan->indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> @@ -676,9 +681,10 @@ EXPORT_SYMBOL_GPL(iio_read_channel_offset);
> int iio_read_channel_processed_scale(struct iio_channel *chan, int *val,
> unsigned int scale)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
> int ret;
>
> - mutex_lock(&chan->indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> if (chan->indio_dev->info == NULL) {
> ret = -ENODEV;
> goto err_unlock;
> @@ -699,7 +705,7 @@ int iio_read_channel_processed_scale(struct iio_channel *chan, int *val,
> }
>
> err_unlock:
> - mutex_unlock(&chan->indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> @@ -733,9 +739,10 @@ int iio_read_avail_channel_attribute(struct iio_channel *chan,
> const int **vals, int *type, int *length,
> enum iio_chan_info_enum attribute)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
> int ret;
>
> - mutex_lock(&chan->indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> if (!chan->indio_dev->info) {
> ret = -ENODEV;
> goto err_unlock;
> @@ -743,7 +750,7 @@ int iio_read_avail_channel_attribute(struct iio_channel *chan,
>
> ret = iio_channel_read_avail(chan, vals, type, length, attribute);
> err_unlock:
> - mutex_unlock(&chan->indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> @@ -815,10 +822,11 @@ static int iio_channel_read_max(struct iio_channel *chan,
>
> int iio_read_max_channel_raw(struct iio_channel *chan, int *val)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
> int ret;
> int type;
>
> - mutex_lock(&chan->indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> if (!chan->indio_dev->info) {
> ret = -ENODEV;
> goto err_unlock;
> @@ -826,7 +834,7 @@ int iio_read_max_channel_raw(struct iio_channel *chan, int *val)
>
> ret = iio_channel_read_max(chan, val, NULL, &type, IIO_CHAN_INFO_RAW);
> err_unlock:
> - mutex_unlock(&chan->indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> @@ -834,10 +842,11 @@ EXPORT_SYMBOL_GPL(iio_read_max_channel_raw);
>
> int iio_get_channel_type(struct iio_channel *chan, enum iio_chan_type *type)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
> int ret = 0;
> /* Need to verify underlying driver has not gone away */
>
> - mutex_lock(&chan->indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> if (chan->indio_dev->info == NULL) {
> ret = -ENODEV;
> goto err_unlock;
> @@ -845,7 +854,7 @@ int iio_get_channel_type(struct iio_channel *chan, enum iio_chan_type *type)
>
> *type = chan->channel->type;
> err_unlock:
> - mutex_unlock(&chan->indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> @@ -861,9 +870,10 @@ static int iio_channel_write(struct iio_channel *chan, int val, int val2,
> int iio_write_channel_attribute(struct iio_channel *chan, int val, int val2,
> enum iio_chan_info_enum attribute)
> {
> + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(chan->indio_dev);
> int ret;
>
> - mutex_lock(&chan->indio_dev->info_exist_lock);
> + mutex_lock(&iio_dev_opaque->info_exist_lock);
> if (chan->indio_dev->info == NULL) {
> ret = -ENODEV;
> goto err_unlock;
> @@ -871,7 +881,7 @@ int iio_write_channel_attribute(struct iio_channel *chan, int val, int val2,
>
> ret = iio_channel_write(chan, val, val2, attribute);
> err_unlock:
> - mutex_unlock(&chan->indio_dev->info_exist_lock);
> + mutex_unlock(&iio_dev_opaque->info_exist_lock);
>
> return ret;
> }
> diff --git a/include/linux/iio/iio-opaque.h b/include/linux/iio/iio-opaque.h
> index 02038fb2d291..538b4b5ef1a9 100644
> --- a/include/linux/iio/iio-opaque.h
> +++ b/include/linux/iio/iio-opaque.h
> @@ -8,6 +8,7 @@
> * @indio_dev: public industrial I/O device information
> * @id: used to identify device internally
> * @driver_module: used to make it harder to undercut users
> + * @info_exist_lock: lock to prevent use during removal
> * @trig_readonly: mark the current trigger immutable
> * @event_interface: event chrdevs associated with interrupt lines
> * @attached_buffers: array of buffers statically attached by the driver
> @@ -32,6 +33,7 @@ struct iio_dev_opaque {
> struct iio_dev indio_dev;
> int id;
> struct module *driver_module;
> + struct mutex info_exist_lock;
> bool trig_readonly;
> struct iio_event_interface *event_interface;
> struct iio_buffer **attached_buffers;
> diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
> index cbc9e9ece0a6..a12bbd8b1e74 100644
> --- a/include/linux/iio/iio.h
> +++ b/include/linux/iio/iio.h
> @@ -510,7 +510,6 @@ struct iio_buffer_setup_ops {
> * @label: [DRIVER] unique name to identify which device this is
> * @info: [DRIVER] callbacks and constant info from driver
> * @clock_id: [INTERN] timestamping clock posix identifier
> - * @info_exist_lock: [INTERN] lock to prevent use during removal
> * @setup_ops: [DRIVER] callbacks to call before and after buffer
> * enable/disable
> * @chrdev: [INTERN] associated character device
> @@ -542,7 +541,6 @@ struct iio_dev {
> const char *label;
> const struct iio_info *info;
> clockid_t clock_id;
> - struct mutex info_exist_lock;
> const struct iio_buffer_setup_ops *setup_ops;
> struct cdev chrdev;
>
> --
> 2.31.1
>
