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linux/mm/cma_sysfs.c
Thomas Weißschuh a4a4659d86 mm: cma: make kobj_type structure constant
Since commit ee6d3dd4ed ("driver core: make kobj_type constant.") the
driver core allows the usage of const struct kobj_type.

Take advantage of this to constify the structure definition to prevent
modification at runtime.

Link: https://lkml.kernel.org/r/20230220-kobj_type-mm-cma-v1-1-45996cff1a81@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-28 16:20:06 -07:00

113 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* CMA SysFS Interface
*
* Copyright (c) 2021 Minchan Kim <minchan@kernel.org>
*/
#include <linux/cma.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include "cma.h"
#define CMA_ATTR_RO(_name) \
static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
void cma_sysfs_account_success_pages(struct cma *cma, unsigned long nr_pages)
{
atomic64_add(nr_pages, &cma->nr_pages_succeeded);
}
void cma_sysfs_account_fail_pages(struct cma *cma, unsigned long nr_pages)
{
atomic64_add(nr_pages, &cma->nr_pages_failed);
}
static inline struct cma *cma_from_kobj(struct kobject *kobj)
{
return container_of(kobj, struct cma_kobject, kobj)->cma;
}
static ssize_t alloc_pages_success_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct cma *cma = cma_from_kobj(kobj);
return sysfs_emit(buf, "%llu\n",
atomic64_read(&cma->nr_pages_succeeded));
}
CMA_ATTR_RO(alloc_pages_success);
static ssize_t alloc_pages_fail_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
struct cma *cma = cma_from_kobj(kobj);
return sysfs_emit(buf, "%llu\n", atomic64_read(&cma->nr_pages_failed));
}
CMA_ATTR_RO(alloc_pages_fail);
static void cma_kobj_release(struct kobject *kobj)
{
struct cma *cma = cma_from_kobj(kobj);
struct cma_kobject *cma_kobj = cma->cma_kobj;
kfree(cma_kobj);
cma->cma_kobj = NULL;
}
static struct attribute *cma_attrs[] = {
&alloc_pages_success_attr.attr,
&alloc_pages_fail_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(cma);
static const struct kobj_type cma_ktype = {
.release = cma_kobj_release,
.sysfs_ops = &kobj_sysfs_ops,
.default_groups = cma_groups,
};
static int __init cma_sysfs_init(void)
{
struct kobject *cma_kobj_root;
struct cma_kobject *cma_kobj;
struct cma *cma;
int i, err;
cma_kobj_root = kobject_create_and_add("cma", mm_kobj);
if (!cma_kobj_root)
return -ENOMEM;
for (i = 0; i < cma_area_count; i++) {
cma_kobj = kzalloc(sizeof(*cma_kobj), GFP_KERNEL);
if (!cma_kobj) {
err = -ENOMEM;
goto out;
}
cma = &cma_areas[i];
cma->cma_kobj = cma_kobj;
cma_kobj->cma = cma;
err = kobject_init_and_add(&cma_kobj->kobj, &cma_ktype,
cma_kobj_root, "%s", cma->name);
if (err) {
kobject_put(&cma_kobj->kobj);
goto out;
}
}
return 0;
out:
while (--i >= 0) {
cma = &cma_areas[i];
kobject_put(&cma->cma_kobj->kobj);
}
kobject_put(cma_kobj_root);
return err;
}
subsys_initcall(cma_sysfs_init);