diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/gpio/gpiolib-cdev.c | 18 | ||||
-rw-r--r-- | drivers/gpio/gpiolib.c | 58 | ||||
-rw-r--r-- | drivers/gpio/gpiolib.h | 17 |
3 files changed, 63 insertions, 30 deletions
diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index d09c7d728365..9dad67ea2597 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -1193,6 +1193,8 @@ static int edge_detector_update(struct line *line, struct gpio_v2_line_config *lc, unsigned int line_idx, u64 edflags) { + u64 eflags; + int ret; u64 active_edflags = READ_ONCE(line->edflags); unsigned int debounce_period_us = gpio_v2_line_config_debounce_period(lc, line_idx); @@ -1204,6 +1206,18 @@ static int edge_detector_update(struct line *line, /* sw debounced and still will be...*/ if (debounce_period_us && READ_ONCE(line->sw_debounced)) { line_set_debounce_period(line, debounce_period_us); + /* + * ensure event fifo is initialised if edge detection + * is now enabled. + */ + eflags = edflags & GPIO_V2_LINE_EDGE_FLAGS; + if (eflags && !kfifo_initialized(&line->req->events)) { + ret = kfifo_alloc(&line->req->events, + line->req->event_buffer_size, + GFP_KERNEL); + if (ret) + return ret; + } return 0; } @@ -2351,7 +2365,7 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, dflags = READ_ONCE(desc->flags); - scoped_guard(srcu, &desc->srcu) { + scoped_guard(srcu, &desc->gdev->desc_srcu) { label = gpiod_get_label(desc); if (label && test_bit(FLAG_REQUESTED, &dflags)) strscpy(info->consumer, label, @@ -2799,11 +2813,11 @@ static int gpio_chrdev_release(struct inode *inode, struct file *file) struct gpio_chardev_data *cdev = file->private_data; struct gpio_device *gdev = cdev->gdev; - bitmap_free(cdev->watched_lines); blocking_notifier_chain_unregister(&gdev->device_notifier, &cdev->device_unregistered_nb); blocking_notifier_chain_unregister(&gdev->line_state_notifier, &cdev->lineinfo_changed_nb); + bitmap_free(cdev->watched_lines); gpio_device_put(gdev); kfree(cdev); diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 94903fc1c145..fa50db0c3605 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -101,6 +101,7 @@ static bool gpiolib_initialized; const char *gpiod_get_label(struct gpio_desc *desc) { + struct gpio_desc_label *label; unsigned long flags; flags = READ_ONCE(desc->flags); @@ -108,23 +109,36 @@ const char *gpiod_get_label(struct gpio_desc *desc) !test_bit(FLAG_REQUESTED, &flags)) return "interrupt"; - return test_bit(FLAG_REQUESTED, &flags) ? - srcu_dereference(desc->label, &desc->srcu) : NULL; + if (!test_bit(FLAG_REQUESTED, &flags)) + return NULL; + + label = srcu_dereference_check(desc->label, &desc->gdev->desc_srcu, + srcu_read_lock_held(&desc->gdev->desc_srcu)); + + return label->str; +} + +static void desc_free_label(struct rcu_head *rh) +{ + kfree(container_of(rh, struct gpio_desc_label, rh)); } static int desc_set_label(struct gpio_desc *desc, const char *label) { - const char *new = NULL, *old; + struct gpio_desc_label *new = NULL, *old; if (label) { - new = kstrdup_const(label, GFP_KERNEL); + new = kzalloc(struct_size(new, str, strlen(label) + 1), + GFP_KERNEL); if (!new) return -ENOMEM; + + strcpy(new->str, label); } old = rcu_replace_pointer(desc->label, new, 1); - synchronize_srcu(&desc->srcu); - kfree_const(old); + if (old) + call_srcu(&desc->gdev->desc_srcu, &old->rh, desc_free_label); return 0; } @@ -695,10 +709,10 @@ EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); static void gpiodev_release(struct device *dev) { struct gpio_device *gdev = to_gpio_device(dev); - unsigned int i; - for (i = 0; i < gdev->ngpio; i++) - cleanup_srcu_struct(&gdev->descs[i].srcu); + /* Call pending kfree()s for descriptor labels. */ + synchronize_srcu(&gdev->desc_srcu); + cleanup_srcu_struct(&gdev->desc_srcu); ida_free(&gpio_ida, gdev->id); kfree_const(gdev->label); @@ -975,6 +989,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, if (ret) goto err_remove_from_list; + ret = init_srcu_struct(&gdev->desc_srcu); + if (ret) + goto err_cleanup_gdev_srcu; + #ifdef CONFIG_PINCTRL INIT_LIST_HEAD(&gdev->pin_ranges); #endif @@ -982,23 +1000,19 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, if (gc->names) { ret = gpiochip_set_desc_names(gc); if (ret) - goto err_cleanup_gdev_srcu; + goto err_cleanup_desc_srcu; } ret = gpiochip_set_names(gc); if (ret) - goto err_cleanup_gdev_srcu; + goto err_cleanup_desc_srcu; ret = gpiochip_init_valid_mask(gc); if (ret) - goto err_cleanup_gdev_srcu; + goto err_cleanup_desc_srcu; for (desc_index = 0; desc_index < gc->ngpio; desc_index++) { struct gpio_desc *desc = &gdev->descs[desc_index]; - ret = init_srcu_struct(&desc->srcu); - if (ret) - goto err_cleanup_desc_srcu; - if (gc->get_direction && gpiochip_line_is_valid(gc, desc_index)) { assign_bit(FLAG_IS_OUT, &desc->flags, !gc->get_direction(gc, desc_index)); @@ -1010,7 +1024,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, ret = of_gpiochip_add(gc); if (ret) - goto err_cleanup_desc_srcu; + goto err_free_valid_mask; ret = gpiochip_add_pin_ranges(gc); if (ret) @@ -1057,10 +1071,10 @@ err_free_hogs: gpiochip_remove_pin_ranges(gc); err_remove_of_chip: of_gpiochip_remove(gc); -err_cleanup_desc_srcu: - while (desc_index--) - cleanup_srcu_struct(&gdev->descs[desc_index].srcu); +err_free_valid_mask: gpiochip_free_valid_mask(gc); +err_cleanup_desc_srcu: + cleanup_srcu_struct(&gdev->desc_srcu); err_cleanup_gdev_srcu: cleanup_srcu_struct(&gdev->srcu); err_remove_from_list: @@ -2390,7 +2404,7 @@ char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset) if (!test_bit(FLAG_REQUESTED, &desc->flags)) return NULL; - guard(srcu)(&desc->srcu); + guard(srcu)(&desc->gdev->desc_srcu); label = kstrdup(gpiod_get_label(desc), GFP_KERNEL); if (!label) @@ -4781,7 +4795,7 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) } for_each_gpio_desc(gc, desc) { - guard(srcu)(&desc->srcu); + guard(srcu)(&desc->gdev->desc_srcu); if (test_bit(FLAG_REQUESTED, &desc->flags)) { gpiod_get_direction(desc); is_out = test_bit(FLAG_IS_OUT, &desc->flags); diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index f67d5991ab1c..8e0e211ebf08 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -31,6 +31,7 @@ * @chip: pointer to the corresponding gpiochip, holding static * data for this device * @descs: array of ngpio descriptors. + * @desc_srcu: ensures consistent state of GPIO descriptors exposed to users * @ngpio: the number of GPIO lines on this GPIO device, equal to the size * of the @descs array. * @can_sleep: indicate whether the GPIO chip driver's callbacks can sleep @@ -61,6 +62,7 @@ struct gpio_device { struct module *owner; struct gpio_chip __rcu *chip; struct gpio_desc *descs; + struct srcu_struct desc_srcu; int base; u16 ngpio; bool can_sleep; @@ -137,6 +139,11 @@ int gpiod_set_transitory(struct gpio_desc *desc, bool transitory); void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action); +struct gpio_desc_label { + struct rcu_head rh; + char str[]; +}; + /** * struct gpio_desc - Opaque descriptor for a GPIO * @@ -145,7 +152,6 @@ void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action); * @label: Name of the consumer * @name: Line name * @hog: Pointer to the device node that hogs this line (if any) - * @srcu: SRCU struct protecting the label pointer. * * These are obtained using gpiod_get() and are preferable to the old * integer-based handles. @@ -177,13 +183,12 @@ struct gpio_desc { #define FLAG_EVENT_CLOCK_HTE 19 /* GPIO CDEV reports hardware timestamps in events */ /* Connection label */ - const char __rcu *label; + struct gpio_desc_label __rcu *label; /* Name of the GPIO */ const char *name; #ifdef CONFIG_OF_DYNAMIC struct device_node *hog; #endif - struct srcu_struct srcu; }; #define gpiod_not_found(desc) (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) @@ -251,7 +256,7 @@ static inline int gpio_chip_hwgpio(const struct gpio_desc *desc) #define gpiod_err(desc, fmt, ...) \ do { \ - scoped_guard(srcu, &desc->srcu) { \ + scoped_guard(srcu, &desc->gdev->desc_srcu) { \ pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), \ gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \ } \ @@ -259,7 +264,7 @@ do { \ #define gpiod_warn(desc, fmt, ...) \ do { \ - scoped_guard(srcu, &desc->srcu) { \ + scoped_guard(srcu, &desc->gdev->desc_srcu) { \ pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), \ gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \ } \ @@ -267,7 +272,7 @@ do { \ #define gpiod_dbg(desc, fmt, ...) \ do { \ - scoped_guard(srcu, &desc->srcu) { \ + scoped_guard(srcu, &desc->gdev->desc_srcu) { \ pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), \ gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \ } \ |