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/char/nwbutton.h | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 drivers/char/nwbutton.h (limited to 'drivers/char/nwbutton.h') diff --git a/drivers/char/nwbutton.h b/drivers/char/nwbutton.h new file mode 100644 index 000000000..f2b9fdc1f --- /dev/null +++ b/drivers/char/nwbutton.h @@ -0,0 +1,40 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __NWBUTTON_H +#define __NWBUTTON_H + +/* + * NetWinder Button Driver- + * Copyright (C) Alex Holden 1998, 1999. + */ + +#ifdef __NWBUTTON_C /* Actually compiling the driver itself */ + +/* Various defines: */ + +#define NUM_PRESSES_REBOOT 2 /* How many presses to activate shutdown */ +#define BUTTON_DELAY 30 /* How many jiffies for sequence to end */ +#define VERSION "0.3" /* Driver version number */ + +/* Structure definitions: */ + +struct button_callback { + void (*callback) (void); + int count; +}; + +/* Function prototypes: */ + +static void button_sequence_finished(struct timer_list *unused); +static irqreturn_t button_handler (int irq, void *dev_id); +int button_init (void); +int button_add_callback (void (*callback) (void), int count); +int button_del_callback (void (*callback) (void)); +static void button_consume_callbacks (int bpcount); + +#else /* Not compiling the driver itself */ + +extern int button_add_callback (void (*callback) (void), int count); +extern int button_del_callback (void (*callback) (void)); + +#endif /* __NWBUTTON_C */ +#endif /* __NWBUTTON_H */ -- cgit v1.3.1