diff options
| author | Jonathan Cameron <jic23@kernel.org> | 2012-02-15 19:48:00 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-24 12:10:02 -0800 |
| commit | ac917a81117ce0286847666b55dd265f6cda8383 (patch) | |
| tree | ea5052ebeb55cc59fc0f3fa28df1560ddfa487f3 /drivers/staging/iio | |
| parent | 08cd9ef4eca0b53cdae190b718e4945408c7d3b8 (diff) | |
staging:iio:core set the iio_dev.info pointer to null on unregister under lock.
This prevents use of provider callbacks after it has been unregistered.
Note that all code using this that can be called from a consumer *must*
check the pointer before using and hold the info_exist_lock throughout
the usage of the callbacks in info.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/iio')
| -rw-r--r-- | drivers/staging/iio/iio.h | 2 | ||||
| -rw-r--r-- | drivers/staging/iio/industrialio-core.c | 4 |
2 files changed, 6 insertions, 0 deletions
diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h index be6ced31f65..478dbe5924c 100644 --- a/drivers/staging/iio/iio.h +++ b/drivers/staging/iio/iio.h @@ -310,6 +310,7 @@ struct iio_buffer_setup_ops { * @chan_attr_group: [INTERN] group for all attrs in base directory * @name: [DRIVER] name of the device. * @info: [DRIVER] callbacks and constant info from driver + * @info_exist_lock: [INTERN] lock to prevent use during removal * @chrdev: [INTERN] associated character device * @groups: [INTERN] attribute groups * @groupcounter: [INTERN] index of next attribute group @@ -340,6 +341,7 @@ struct iio_dev { struct attribute_group chan_attr_group; const char *name; const struct iio_info *info; + struct mutex info_exist_lock; const struct iio_buffer_setup_ops *setup_ops; struct cdev chrdev; #define IIO_MAX_GROUPS 6 diff --git a/drivers/staging/iio/industrialio-core.c b/drivers/staging/iio/industrialio-core.c index e4824fe8b40..3a2d0802662 100644 --- a/drivers/staging/iio/industrialio-core.c +++ b/drivers/staging/iio/industrialio-core.c @@ -594,6 +594,7 @@ struct iio_dev *iio_allocate_device(int sizeof_priv) device_initialize(&dev->dev); dev_set_drvdata(&dev->dev, (void *)dev); mutex_init(&dev->mlock); + mutex_init(&dev->info_exist_lock); dev->id = ida_simple_get(&iio_ida, 0, 0, GFP_KERNEL); if (dev->id < 0) { @@ -718,6 +719,9 @@ EXPORT_SYMBOL(iio_device_register); void iio_device_unregister(struct iio_dev *indio_dev) { + mutex_lock(&indio_dev->info_exist_lock); + indio_dev->info = NULL; + mutex_unlock(&indio_dev->info_exist_lock); device_unregister(&indio_dev->dev); } EXPORT_SYMBOL(iio_device_unregister); |