/*
 * GPL HEADER START
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License version 2 for more details (a copy is included
 * in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU General Public License
 * version 2 along with this program; If not, see
 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 * GPL HEADER END
 */
/*
 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 2012, 2015, Intel Corporation.
 */
/*
 * This file is part of Lustre, http://www.lustre.org/
 * Lustre is a trademark of Sun Microsystems, Inc.
 */

#define DEBUG_SUBSYSTEM S_LNET

#include <libcfs/libcfs.h>
#include <libcfs/libcfs_crypto.h>
#include <lnet/lib-lnet.h>

static DECLARE_RWSEM(ioctl_list_sem);
static LIST_HEAD(ioctl_list);

int libcfs_register_ioctl(struct libcfs_ioctl_handler *hand)
{
	int rc = 0;

	down_write(&ioctl_list_sem);
	if (!list_empty(&hand->item))
		rc = -EBUSY;
	else
		list_add_tail(&hand->item, &ioctl_list);
	up_write(&ioctl_list_sem);

	return rc;
}
EXPORT_SYMBOL(libcfs_register_ioctl);

int libcfs_deregister_ioctl(struct libcfs_ioctl_handler *hand)
{
	int rc = 0;

	down_write(&ioctl_list_sem);
	if (list_empty(&hand->item))
		rc = -ENOENT;
	else
		list_del_init(&hand->item);
	up_write(&ioctl_list_sem);

	return rc;
}
EXPORT_SYMBOL(libcfs_deregister_ioctl);

int libcfs_ioctl(unsigned long cmd, void __user *uparam)
{
	struct libcfs_ioctl_data *data = NULL;
	struct libcfs_ioctl_hdr  *hdr;
	int			  err;
	ENTRY;

	/* 'cmd' and permissions get checked in our arch-specific caller */
	err = libcfs_ioctl_getdata(&hdr, uparam);
	if (err != 0) {
		CDEBUG_LIMIT(D_ERROR,
			     "libcfs ioctl: data header error %d\n", err);
		RETURN(err);
	}

	if (hdr->ioc_version == LIBCFS_IOCTL_VERSION) {
		/* The libcfs_ioctl_data_adjust() function performs adjustment
		 * operations on the libcfs_ioctl_data structure to make
		 * it usable by the code.  This doesn't need to be called
		 * for new data structures added. */
		data = container_of(hdr, struct libcfs_ioctl_data, ioc_hdr);
		err = libcfs_ioctl_data_adjust(data);
		if (err != 0)
			GOTO(out, err);
	}

	CDEBUG(D_IOCTL, "libcfs ioctl cmd %lu\n", cmd);
	switch (cmd) {
	case IOC_LIBCFS_CLEAR_DEBUG:
		libcfs_debug_clear_buffer();
		break;
	case IOC_LIBCFS_MARK_DEBUG:
		if (data == NULL ||
		    data->ioc_inlbuf1 == NULL ||
		    data->ioc_inlbuf1[data->ioc_inllen1 - 1] != '\0')
			GOTO(out, err = -EINVAL);

		libcfs_debug_mark_buffer(data->ioc_inlbuf1);
		break;

	default: {
		struct libcfs_ioctl_handler *hand;

		err = -EINVAL;
		down_read(&ioctl_list_sem);
		list_for_each_entry(hand, &ioctl_list, item) {
			err = hand->handle_ioctl(cmd, hdr);
			if (err == -EINVAL)
				continue;

			if (err == 0) {
				if (copy_to_user(uparam, hdr, hdr->ioc_len))
					err = -EFAULT;
			}
			break;
		}
		up_read(&ioctl_list_sem);
		break; }
	}
out:
	LIBCFS_FREE(hdr, hdr->ioc_len);
	RETURN(err);
}

static int __init libcfs_init(void)
{
	int rc;

	rc = libcfs_debug_init(5 * 1024 * 1024);
	if (rc < 0) {
		printk(KERN_ERR "LustreError: libcfs_debug_init: %d\n", rc);
		return (rc);
	}

	rc = cfs_cpu_init();
	if (rc != 0)
		goto cleanup_debug;

	rc = misc_register(&libcfs_dev);
	if (rc) {
		CERROR("misc_register: error %d\n", rc);
		goto cleanup_cpu;
	}

	rc = cfs_wi_startup();
	if (rc) {
		CERROR("initialize workitem: error %d\n", rc);
		goto cleanup_deregister;
	}

	/* max to 4 threads, should be enough for rehash */
	rc = min(cfs_cpt_weight(cfs_cpt_table, CFS_CPT_ANY), 4);
	rc = cfs_wi_sched_create("cfs_rh", cfs_cpt_table, CFS_CPT_ANY,
				 rc, &cfs_sched_rehash);
	if (rc != 0) {
		CERROR("Startup workitem scheduler: error: %d\n", rc);
		goto cleanup_deregister;
	}

	rc = cfs_crypto_register();
	if (rc) {
		CERROR("cfs_crypto_regster: error %d\n", rc);
		goto cleanup_wi;
	}


	rc = insert_proc();
	if (rc) {
		CERROR("insert_proc: error %d\n", rc);
		goto cleanup_crypto;
	}

	CDEBUG (D_OTHER, "portals setup OK\n");
	return 0;
cleanup_crypto:
	cfs_crypto_unregister();
cleanup_wi:
	cfs_wi_shutdown();
cleanup_deregister:
	misc_deregister(&libcfs_dev);
cleanup_cpu:
	cfs_cpu_fini();
cleanup_debug:
	libcfs_debug_cleanup();
	return rc;
}

static void __exit libcfs_exit(void)
{
	int rc;

	remove_proc();

	CDEBUG(D_MALLOC, "before Portals cleanup: kmem %d\n",
	       atomic_read(&libcfs_kmemory));

	if (cfs_sched_rehash != NULL) {
		cfs_wi_sched_destroy(cfs_sched_rehash);
		cfs_sched_rehash = NULL;
	}

	cfs_crypto_unregister();
	cfs_wi_shutdown();

	misc_deregister(&libcfs_dev);

	cfs_cpu_fini();

	if (atomic_read(&libcfs_kmemory) != 0)
		CERROR("Portals memory leaked: %d bytes\n",
		       atomic_read(&libcfs_kmemory));

	rc = libcfs_debug_cleanup();
	if (rc)
		printk(KERN_ERR "LustreError: libcfs_debug_cleanup: %d\n",
		       rc);
}

MODULE_AUTHOR("OpenSFS, Inc. <http://www.lustre.org/>");
MODULE_DESCRIPTION("Lustre helper library");
MODULE_VERSION(LIBCFS_VERSION);
MODULE_LICENSE("GPL");

module_init(libcfs_init);
module_exit(libcfs_exit);