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/macintosh/macio_sysfs.c | 82 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 drivers/macintosh/macio_sysfs.c (limited to 'drivers/macintosh/macio_sysfs.c') diff --git a/drivers/macintosh/macio_sysfs.c b/drivers/macintosh/macio_sysfs.c new file mode 100644 index 000000000..2bbe359b2 --- /dev/null +++ b/drivers/macintosh/macio_sysfs.c @@ -0,0 +1,82 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include + +static ssize_t +compatible_show (struct device *dev, struct device_attribute *attr, char *buf) +{ + struct platform_device *of; + const char *compat; + int cplen; + int length = 0; + + of = &to_macio_device (dev)->ofdev; + compat = of_get_property(of->dev.of_node, "compatible", &cplen); + if (!compat) { + *buf = '\0'; + return 0; + } + while (cplen > 0) { + int l; + length += sprintf (buf, "%s\n", compat); + buf += length; + l = strlen (compat) + 1; + compat += l; + cplen -= l; + } + + return length; +} +static DEVICE_ATTR_RO(compatible); + +static ssize_t modalias_show (struct device *dev, struct device_attribute *attr, + char *buf) +{ + return of_device_modalias(dev, buf, PAGE_SIZE); +} + +static ssize_t devspec_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct platform_device *ofdev; + + ofdev = to_platform_device(dev); + return sprintf(buf, "%pOF\n", ofdev->dev.of_node); +} +static DEVICE_ATTR_RO(modalias); +static DEVICE_ATTR_RO(devspec); + +static ssize_t name_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%pOFn\n", dev->of_node); +} +static DEVICE_ATTR_RO(name); + +static ssize_t type_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%s\n", of_node_get_device_type(dev->of_node)); +} +static DEVICE_ATTR_RO(type); + +static struct attribute *macio_dev_attrs[] = { + &dev_attr_name.attr, + &dev_attr_type.attr, + &dev_attr_compatible.attr, + &dev_attr_modalias.attr, + &dev_attr_devspec.attr, + NULL, +}; + +static const struct attribute_group macio_dev_group = { + .attrs = macio_dev_attrs, +}; + +const struct attribute_group *macio_dev_groups[] = { + &macio_dev_group, + NULL, +}; -- cgit v1.3.1