From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- drivers/gpio/gpiolib-shared.h | 51 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 drivers/gpio/gpiolib-shared.h (limited to 'drivers/gpio/gpiolib-shared.h') diff --git a/drivers/gpio/gpiolib-shared.h b/drivers/gpio/gpiolib-shared.h new file mode 100644 index 000000000..618756f6c --- /dev/null +++ b/drivers/gpio/gpiolib-shared.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __LINUX_GPIO_SHARED_H +#define __LINUX_GPIO_SHARED_H + +#include + +struct gpio_device; +struct gpio_desc; +struct device; +struct fwnode_handle; + +#if IS_ENABLED(CONFIG_GPIO_SHARED) + +int gpiochip_setup_shared(struct gpio_chip *gc); +void gpio_device_teardown_shared(struct gpio_device *gdev); +int gpio_shared_add_proxy_lookup(struct device *consumer, + struct fwnode_handle *fwnode, + const char *con_id, unsigned long lflags); + +#else + +static inline int gpiochip_setup_shared(struct gpio_chip *gc) +{ + return 0; +} + +static inline void gpio_device_teardown_shared(struct gpio_device *gdev) { } + +static inline int gpio_shared_add_proxy_lookup(struct device *consumer, + struct fwnode_handle *fwnode, + const char *con_id, + unsigned long lflags) +{ + return 0; +} + +#endif /* CONFIG_GPIO_SHARED */ + +struct gpio_shared_desc { + struct gpio_desc *desc; + unsigned long cfg; + unsigned int usecnt; + unsigned int votecnt; + int def_val; + struct mutex mutex; /* serializes all proxy operations on this descriptor */ +}; + +struct gpio_shared_desc *devm_gpiod_shared_get(struct device *dev); + +#endif /* __LINUX_GPIO_SHARED_H */ -- cgit v1.3.1