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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
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/*
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* Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
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*/
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#include <linux/kernel.h>
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#include <linux/spinlock.h>
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#include <linux/device.h>
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#include <linux/idr.h>
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#include <linux/kdev_t.h>
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#include <linux/err.h>
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#include <linux/dca.h>
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#include <linux/gfp.h>
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#include <linux/export.h>
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static const struct class dca_class = {
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.name = "dca",
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};
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static struct idr dca_idr;
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static spinlock_t dca_idr_lock;
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int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot)
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{
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struct device *cd;
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static int req_count;
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cd = device_create(&dca_class, dca->cd, MKDEV(0, slot + 1), NULL,
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"requester%d", req_count++);
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return PTR_ERR_OR_ZERO(cd);
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}
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void dca_sysfs_remove_req(struct dca_provider *dca, int slot)
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{
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device_destroy(&dca_class, MKDEV(0, slot + 1));
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}
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int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)
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{
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struct device *cd;
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int ret;
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idr_preload(GFP_KERNEL);
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spin_lock(&dca_idr_lock);
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ret = idr_alloc(&dca_idr, dca, 0, 0, GFP_NOWAIT);
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if (ret >= 0)
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dca->id = ret;
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spin_unlock(&dca_idr_lock);
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idr_preload_end();
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if (ret < 0)
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return ret;
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cd = device_create(&dca_class, dev, MKDEV(0, 0), NULL, "dca%d", dca->id);
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if (IS_ERR(cd)) {
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spin_lock(&dca_idr_lock);
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idr_remove(&dca_idr, dca->id);
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spin_unlock(&dca_idr_lock);
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return PTR_ERR(cd);
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}
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dca->cd = cd;
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return 0;
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}
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void dca_sysfs_remove_provider(struct dca_provider *dca)
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{
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device_unregister(dca->cd);
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dca->cd = NULL;
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spin_lock(&dca_idr_lock);
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idr_remove(&dca_idr, dca->id);
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spin_unlock(&dca_idr_lock);
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}
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int __init dca_sysfs_init(void)
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{
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int err;
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idr_init(&dca_idr);
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spin_lock_init(&dca_idr_lock);
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err = class_register(&dca_class);
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if (err) {
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idr_destroy(&dca_idr);
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return err;
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}
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return 0;
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}
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void __exit dca_sysfs_exit(void)
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{
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class_unregister(&dca_class);
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idr_destroy(&dca_idr);
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}
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