From 4a08069461ac9822855116d24fbf11d5fb223cd1 Mon Sep 17 00:00:00 2001 From: Dmitry Rokosov Date: Tue, 7 Jun 2022 18:39:18 +0000 Subject: iio: trigger: warn about non-registered iio trigger getting attempt As a part of patch series about wrong trigger register() and get() calls order in the some IIO drivers trigger initialization path: https://lore.kernel.org/all/20220524181150.9240-1-ddrokosov@sberdevices.ru/ runtime WARN_ONCE() is added to alarm IIO driver authors who make such a mistake. When an IIO driver allocates a new IIO trigger, it should register it before calling the get() operation. In other words, each IIO driver must abide by IIO trigger alloc()/register()/get() calls order. Signed-off-by: Dmitry Rokosov Link: https://lore.kernel.org/r/20220607183907.20017-1-ddrokosov@sberdevices.ru Signed-off-by: Jonathan Cameron --- include/linux/iio/trigger.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/iio/trigger.h') diff --git a/include/linux/iio/trigger.h b/include/linux/iio/trigger.h index 4c69b144677b..03b1d6863436 100644 --- a/include/linux/iio/trigger.h +++ b/include/linux/iio/trigger.h @@ -93,6 +93,11 @@ static inline void iio_trigger_put(struct iio_trigger *trig) static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig) { get_device(&trig->dev); + + WARN_ONCE(list_empty(&trig->list), + "Getting non-registered iio trigger %s is prohibited\n", + trig->name); + __module_get(trig->owner); return trig; -- cgit v1.2.3 From bc72d938c149197688ae3b3ecaa25d4aee8653cb Mon Sep 17 00:00:00 2001 From: Dmitry Rokosov Date: Wed, 1 Jun 2022 17:48:32 +0000 Subject: iio: trigger: move trig->owner init to trigger allocate() stage To provide a new IIO trigger to the IIO core, usually driver executes the following pipeline: allocate()/register()/get(). Before, IIO core assigned trig->owner as a pointer to the module which registered this trigger at the register() stage. But actually the trigger object is owned by the module earlier, on the allocate() stage, when trigger object is successfully allocated for the driver. This patch moves trig->owner initialization from register() stage of trigger initialization pipeline to allocate() stage to eliminate all misunderstandings and time gaps between trigger object creation and owner acquiring. Signed-off-by: Dmitry Rokosov Link: https://lore.kernel.org/r/20220601174837.20292-1-ddrokosov@sberdevices.ru Signed-off-by: Jonathan Cameron --- drivers/iio/industrialio-trigger.c | 46 +++++++++++++++++++++----------------- include/linux/iio/iio.h | 9 +++++--- include/linux/iio/trigger.h | 21 +++++++++-------- 3 files changed, 41 insertions(+), 35 deletions(-) (limited to 'include/linux/iio/trigger.h') diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c index 26d610d4cbb8..efc01584b3f9 100644 --- a/drivers/iio/industrialio-trigger.c +++ b/drivers/iio/industrialio-trigger.c @@ -63,13 +63,10 @@ ATTRIBUTE_GROUPS(iio_trig_dev); static struct iio_trigger *__iio_trigger_find_by_name(const char *name); -int __iio_trigger_register(struct iio_trigger *trig_info, - struct module *this_mod) +int iio_trigger_register(struct iio_trigger *trig_info) { int ret; - trig_info->owner = this_mod; - trig_info->id = ida_alloc(&iio_trigger_ida, GFP_KERNEL); if (trig_info->id < 0) return trig_info->id; @@ -100,7 +97,7 @@ error_unregister_id: ida_free(&iio_trigger_ida, trig_info->id); return ret; } -EXPORT_SYMBOL(__iio_trigger_register); +EXPORT_SYMBOL(iio_trigger_register); void iio_trigger_unregister(struct iio_trigger *trig_info) { @@ -547,8 +544,9 @@ static void iio_trig_subirqunmask(struct irq_data *d) trig->subirqs[d->irq - trig->subirq_base].enabled = true; } -static __printf(2, 0) +static __printf(3, 0) struct iio_trigger *viio_trigger_alloc(struct device *parent, + struct module *this_mod, const char *fmt, va_list vargs) { @@ -578,6 +576,8 @@ struct iio_trigger *viio_trigger_alloc(struct device *parent, INIT_LIST_HEAD(&trig->list); + trig->owner = this_mod; + trig->subirq_chip.name = trig->name; trig->subirq_chip.irq_mask = &iio_trig_subirqmask; trig->subirq_chip.irq_unmask = &iio_trig_subirqunmask; @@ -598,8 +598,9 @@ free_trig: } /** - * iio_trigger_alloc - Allocate a trigger + * __iio_trigger_alloc - Allocate a trigger * @parent: Device to allocate iio_trigger for + * @this_mod: module allocating the trigger * @fmt: trigger name format. If it includes format * specifiers, the additional arguments following * format are formatted and inserted in the resulting @@ -607,18 +608,20 @@ free_trig: * RETURNS: * Pointer to allocated iio_trigger on success, NULL on failure. */ -struct iio_trigger *iio_trigger_alloc(struct device *parent, const char *fmt, ...) +struct iio_trigger *__iio_trigger_alloc(struct device *parent, + struct module *this_mod, + const char *fmt, ...) { struct iio_trigger *trig; va_list vargs; va_start(vargs, fmt); - trig = viio_trigger_alloc(parent, fmt, vargs); + trig = viio_trigger_alloc(parent, this_mod, fmt, vargs); va_end(vargs); return trig; } -EXPORT_SYMBOL(iio_trigger_alloc); +EXPORT_SYMBOL(__iio_trigger_alloc); void iio_trigger_free(struct iio_trigger *trig) { @@ -633,10 +636,11 @@ static void devm_iio_trigger_release(struct device *dev, void *res) } /** - * devm_iio_trigger_alloc - Resource-managed iio_trigger_alloc() + * __devm_iio_trigger_alloc - Resource-managed iio_trigger_alloc() * Managed iio_trigger_alloc. iio_trigger allocated with this function is * automatically freed on driver detach. * @parent: Device to allocate iio_trigger for + * @this_mod: module allocating the trigger * @fmt: trigger name format. If it includes format * specifiers, the additional arguments following * format are formatted and inserted in the resulting @@ -646,7 +650,9 @@ static void devm_iio_trigger_release(struct device *dev, void *res) * RETURNS: * Pointer to allocated iio_trigger on success, NULL on failure. */ -struct iio_trigger *devm_iio_trigger_alloc(struct device *parent, const char *fmt, ...) +struct iio_trigger *__devm_iio_trigger_alloc(struct device *parent, + struct module *this_mod, + const char *fmt, ...) { struct iio_trigger **ptr, *trig; va_list vargs; @@ -658,7 +664,7 @@ struct iio_trigger *devm_iio_trigger_alloc(struct device *parent, const char *fm /* use raw alloc_dr for kmalloc caller tracing */ va_start(vargs, fmt); - trig = viio_trigger_alloc(parent, fmt, vargs); + trig = viio_trigger_alloc(parent, this_mod, fmt, vargs); va_end(vargs); if (trig) { *ptr = trig; @@ -669,7 +675,7 @@ struct iio_trigger *devm_iio_trigger_alloc(struct device *parent, const char *fm return trig; } -EXPORT_SYMBOL_GPL(devm_iio_trigger_alloc); +EXPORT_SYMBOL_GPL(__devm_iio_trigger_alloc); static void devm_iio_trigger_unreg(void *trigger_info) { @@ -677,10 +683,9 @@ static void devm_iio_trigger_unreg(void *trigger_info) } /** - * __devm_iio_trigger_register - Resource-managed iio_trigger_register() + * devm_iio_trigger_register - Resource-managed iio_trigger_register() * @dev: device this trigger was allocated for * @trig_info: trigger to register - * @this_mod: module registering the trigger * * Managed iio_trigger_register(). The IIO trigger registered with this * function is automatically unregistered on driver detach. This function @@ -690,19 +695,18 @@ static void devm_iio_trigger_unreg(void *trigger_info) * RETURNS: * 0 on success, negative error number on failure. */ -int __devm_iio_trigger_register(struct device *dev, - struct iio_trigger *trig_info, - struct module *this_mod) +int devm_iio_trigger_register(struct device *dev, + struct iio_trigger *trig_info) { int ret; - ret = __iio_trigger_register(trig_info, this_mod); + ret = iio_trigger_register(trig_info); if (ret) return ret; return devm_add_action_or_reset(dev, devm_iio_trigger_unreg, trig_info); } -EXPORT_SYMBOL_GPL(__devm_iio_trigger_register); +EXPORT_SYMBOL_GPL(devm_iio_trigger_register); bool iio_trigger_using_own(struct iio_dev *indio_dev) { diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index d9b4a9ca9a0f..5dfbfc991c69 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -727,10 +727,13 @@ static inline void *iio_priv(const struct iio_dev *indio_dev) void iio_device_free(struct iio_dev *indio_dev); struct iio_dev *devm_iio_device_alloc(struct device *parent, int sizeof_priv); -__printf(2, 3) -struct iio_trigger *devm_iio_trigger_alloc(struct device *parent, - const char *fmt, ...); +#define devm_iio_trigger_alloc(parent, fmt, ...) \ + __devm_iio_trigger_alloc((parent), THIS_MODULE, (fmt), ##__VA_ARGS__) +__printf(3, 4) +struct iio_trigger *__devm_iio_trigger_alloc(struct device *parent, + struct module *this_mod, + const char *fmt, ...); /** * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry * @indio_dev: IIO device structure for device diff --git a/include/linux/iio/trigger.h b/include/linux/iio/trigger.h index 03b1d6863436..f6360d9a492d 100644 --- a/include/linux/iio/trigger.h +++ b/include/linux/iio/trigger.h @@ -131,16 +131,10 @@ static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig) * iio_trigger_register() - register a trigger with the IIO core * @trig_info: trigger to be registered **/ -#define iio_trigger_register(trig_info) \ - __iio_trigger_register((trig_info), THIS_MODULE) -int __iio_trigger_register(struct iio_trigger *trig_info, - struct module *this_mod); +int iio_trigger_register(struct iio_trigger *trig_info); -#define devm_iio_trigger_register(dev, trig_info) \ - __devm_iio_trigger_register((dev), (trig_info), THIS_MODULE) -int __devm_iio_trigger_register(struct device *dev, - struct iio_trigger *trig_info, - struct module *this_mod); +int devm_iio_trigger_register(struct device *dev, + struct iio_trigger *trig_info); /** * iio_trigger_unregister() - unregister a trigger from the core @@ -168,8 +162,13 @@ void iio_trigger_poll_chained(struct iio_trigger *trig); irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private); -__printf(2, 3) -struct iio_trigger *iio_trigger_alloc(struct device *parent, const char *fmt, ...); +#define iio_trigger_alloc(parent, fmt, ...) \ + __iio_trigger_alloc((parent), THIS_MODULE, (fmt), ##__VA_ARGS__) + +__printf(3, 4) +struct iio_trigger *__iio_trigger_alloc(struct device *parent, + struct module *this_mod, + const char *fmt, ...); void iio_trigger_free(struct iio_trigger *trig); /** -- cgit v1.2.3