1 | /* |
2 | * Copyright (c) 2000-2021 Apple Computer, Inc. All rights reserved. |
3 | * |
4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ |
5 | * |
6 | * This file contains Original Code and/or Modifications of Original Code |
7 | * as defined in and that are subject to the Apple Public Source License |
8 | * Version 2.0 (the 'License'). You may not use this file except in |
9 | * compliance with the License. The rights granted to you under the License |
10 | * may not be used to create, or enable the creation or redistribution of, |
11 | * unlawful or unlicensed copies of an Apple operating system, or to |
12 | * circumvent, violate, or enable the circumvention or violation of, any |
13 | * terms of an Apple operating system software license agreement. |
14 | * |
15 | * Please obtain a copy of the License at |
16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. |
17 | * |
18 | * The Original Code and all software distributed under the License are |
19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
23 | * Please see the License for the specific language governing rights and |
24 | * limitations under the License. |
25 | * |
26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
27 | */ |
28 | |
29 | #include <kern/kalloc.h> |
30 | #include <libkern/OSAtomic.h> |
31 | #include <sys/errno.h> |
32 | #include <net/init.h> |
33 | #include <libkern/libkern.h> |
34 | #include <string.h> |
35 | |
36 | struct init_list_entry { |
37 | struct init_list_entry *next; |
38 | net_init_func_ptr func; |
39 | }; |
40 | |
41 | #define LIST_RAN ((struct init_list_entry*)0xffffffff) |
42 | static struct init_list_entry *list_head = 0; |
43 | |
44 | errno_t |
45 | net_init_add( |
46 | net_init_func_ptr init_func) |
47 | { |
48 | struct init_list_entry *entry; |
49 | |
50 | if (init_func == 0) { |
51 | return EINVAL; |
52 | } |
53 | |
54 | /* Check if we've already started */ |
55 | if (list_head == LIST_RAN) { |
56 | return EALREADY; |
57 | } |
58 | |
59 | entry = kalloc_type(struct init_list_entry, |
60 | Z_WAITOK | Z_ZERO | Z_NOFAIL); |
61 | |
62 | entry->func = init_func; |
63 | |
64 | do { |
65 | entry->next = list_head; |
66 | |
67 | if (entry->next == LIST_RAN) { |
68 | /* List already ran, cleanup and call the function */ |
69 | kfree_type(struct init_list_entry, entry); |
70 | return EALREADY; |
71 | } |
72 | } while (!OSCompareAndSwapPtr(entry->next, entry, &list_head)); |
73 | |
74 | return 0; |
75 | } |
76 | |
77 | __private_extern__ void |
78 | net_init_run(void) |
79 | { |
80 | struct init_list_entry *backward_head = 0; |
81 | struct init_list_entry *forward_head = 0; |
82 | struct init_list_entry *current = 0; |
83 | |
84 | /* |
85 | * Grab the list, replacing the head with 0xffffffff to indicate |
86 | * that we've already run. |
87 | */ |
88 | do { |
89 | backward_head = list_head; |
90 | } while (!OSCompareAndSwapPtr(backward_head, LIST_RAN, &list_head)); |
91 | |
92 | /* Reverse the order of the list */ |
93 | while (backward_head != 0) { |
94 | current = backward_head; |
95 | backward_head = current->next; |
96 | current->next = forward_head; |
97 | forward_head = current; |
98 | } |
99 | |
100 | /* Call each function pointer registered */ |
101 | while (forward_head != 0) { |
102 | current = forward_head; |
103 | forward_head = current->next; |
104 | current->func(); |
105 | kfree_type(struct init_list_entry, current); |
106 | } |
107 | } |
108 | |