mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-11 21:14:07 +08:00
d7d3ae441e
The driver core allows for struct class to be in read-only memory. Move the dca_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at boot time. Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com> Link: https://lore.kernel.org/r/20240412151726.189030-1-ivan.orlov0322@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
95 lines
1.8 KiB
C
95 lines
1.8 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/device.h>
|
|
#include <linux/idr.h>
|
|
#include <linux/kdev_t.h>
|
|
#include <linux/err.h>
|
|
#include <linux/dca.h>
|
|
#include <linux/gfp.h>
|
|
#include <linux/export.h>
|
|
|
|
static const struct class dca_class = {
|
|
.name = "dca",
|
|
};
|
|
static struct idr dca_idr;
|
|
static spinlock_t dca_idr_lock;
|
|
|
|
int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot)
|
|
{
|
|
struct device *cd;
|
|
static int req_count;
|
|
|
|
cd = device_create(&dca_class, dca->cd, MKDEV(0, slot + 1), NULL,
|
|
"requester%d", req_count++);
|
|
return PTR_ERR_OR_ZERO(cd);
|
|
}
|
|
|
|
void dca_sysfs_remove_req(struct dca_provider *dca, int slot)
|
|
{
|
|
device_destroy(&dca_class, MKDEV(0, slot + 1));
|
|
}
|
|
|
|
int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)
|
|
{
|
|
struct device *cd;
|
|
int ret;
|
|
|
|
idr_preload(GFP_KERNEL);
|
|
spin_lock(&dca_idr_lock);
|
|
|
|
ret = idr_alloc(&dca_idr, dca, 0, 0, GFP_NOWAIT);
|
|
if (ret >= 0)
|
|
dca->id = ret;
|
|
|
|
spin_unlock(&dca_idr_lock);
|
|
idr_preload_end();
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
cd = device_create(&dca_class, dev, MKDEV(0, 0), NULL, "dca%d", dca->id);
|
|
if (IS_ERR(cd)) {
|
|
spin_lock(&dca_idr_lock);
|
|
idr_remove(&dca_idr, dca->id);
|
|
spin_unlock(&dca_idr_lock);
|
|
return PTR_ERR(cd);
|
|
}
|
|
dca->cd = cd;
|
|
return 0;
|
|
}
|
|
|
|
void dca_sysfs_remove_provider(struct dca_provider *dca)
|
|
{
|
|
device_unregister(dca->cd);
|
|
dca->cd = NULL;
|
|
spin_lock(&dca_idr_lock);
|
|
idr_remove(&dca_idr, dca->id);
|
|
spin_unlock(&dca_idr_lock);
|
|
}
|
|
|
|
int __init dca_sysfs_init(void)
|
|
{
|
|
int err;
|
|
|
|
idr_init(&dca_idr);
|
|
spin_lock_init(&dca_idr_lock);
|
|
|
|
err = class_register(&dca_class);
|
|
if (err) {
|
|
idr_destroy(&dca_idr);
|
|
return err;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void __exit dca_sysfs_exit(void)
|
|
{
|
|
class_unregister(&dca_class);
|
|
idr_destroy(&dca_idr);
|
|
}
|
|
|