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/rtc/rtc-starfire.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 drivers/rtc/rtc-starfire.c (limited to 'drivers/rtc/rtc-starfire.c') diff --git a/drivers/rtc/rtc-starfire.c b/drivers/rtc/rtc-starfire.c new file mode 100644 index 000000000..fbd1ed41c --- /dev/null +++ b/drivers/rtc/rtc-starfire.c @@ -0,0 +1,60 @@ +/* rtc-starfire.c: Starfire platform RTC driver. + * + * Author: David S. Miller + * License: GPL + * + * Copyright (C) 2008 David S. Miller + */ + +#include +#include +#include +#include + +#include + +static u32 starfire_get_time(void) +{ + static char obp_gettod[32]; + static u32 unix_tod; + + sprintf(obp_gettod, "h# %08x unix-gettod", + (unsigned int) (long) &unix_tod); + prom_feval(obp_gettod); + + return unix_tod; +} + +static int starfire_read_time(struct device *dev, struct rtc_time *tm) +{ + rtc_time64_to_tm(starfire_get_time(), tm); + return 0; +} + +static const struct rtc_class_ops starfire_rtc_ops = { + .read_time = starfire_read_time, +}; + +static int __init starfire_rtc_probe(struct platform_device *pdev) +{ + struct rtc_device *rtc; + + rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + rtc->ops = &starfire_rtc_ops; + rtc->range_max = U32_MAX; + + platform_set_drvdata(pdev, rtc); + + return devm_rtc_register_device(rtc); +} + +static struct platform_driver starfire_rtc_driver = { + .driver = { + .name = "rtc-starfire", + }, +}; + +builtin_platform_driver_probe(starfire_rtc_driver, starfire_rtc_probe); -- cgit v1.3.1