1/*
2 * Copyright (c) 2016 Apple 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#include <stddef.h>
29#include <kern/debug.h>
30#include <kern/locks.h>
31#include <kern/thread.h>
32#include <kern/thread_call.h>
33#include <net/nwk_wq.h>
34#include <sys/proc_internal.h>
35#include <sys/systm.h>
36#include <sys/mcache.h>
37
38static TAILQ_HEAD(, nwk_wq_entry) nwk_wq_head =
39 TAILQ_HEAD_INITIALIZER(nwk_wq_head);
40static LCK_GRP_DECLARE(nwk_wq_lock_group, "Network work queue lock");
41static LCK_MTX_DECLARE(nwk_wq_lock, &nwk_wq_lock_group);
42
43/* Wait channel for Network work queue */
44static void *nwk_wq_waitch = NULL;
45static void nwk_wq_thread_func(void *, wait_result_t);
46
47static int nwk_wq_thread_cont(int err);
48static void nwk_wq_thread_func(void *v, wait_result_t w);
49
50void
51nwk_wq_init(void)
52{
53 thread_t nwk_wq_thread __single = THREAD_NULL;
54
55 if (kernel_thread_start(continuation: nwk_wq_thread_func,
56 NULL, new_thread: &nwk_wq_thread) != KERN_SUCCESS) {
57 panic_plain("%s: couldn't create network work queue thread", __func__);
58 /* NOTREACHED */
59 }
60 thread_deallocate(thread: nwk_wq_thread);
61}
62
63static int
64nwk_wq_thread_cont(int err)
65{
66 TAILQ_HEAD(, nwk_wq_entry) temp_nwk_wq_head;
67 struct nwk_wq_entry *nwk_item __single;
68 struct nwk_wq_entry *nwk_item_next __single;
69
70#pragma unused(err)
71 for (;;) {
72 nwk_item = NULL;
73 nwk_item_next = NULL;
74 TAILQ_INIT(&temp_nwk_wq_head);
75
76 LCK_MTX_ASSERT(&nwk_wq_lock, LCK_MTX_ASSERT_OWNED);
77 while (TAILQ_FIRST(&nwk_wq_head) == NULL) {
78 (void) msleep0(chan: &nwk_wq_waitch, mtx: &nwk_wq_lock,
79 pri: (PZERO - 1), wmesg: "nwk_wq_thread_cont", timo: 0,
80 continuation: nwk_wq_thread_cont);
81 /* NOTREACHED */
82 }
83
84 TAILQ_SWAP(&temp_nwk_wq_head, &nwk_wq_head, nwk_wq_entry, nwk_wq_link);
85 VERIFY(TAILQ_EMPTY(&nwk_wq_head));
86 lck_mtx_unlock(lck: &nwk_wq_lock);
87
88 VERIFY(TAILQ_FIRST(&temp_nwk_wq_head) != NULL);
89 TAILQ_FOREACH_SAFE(nwk_item, &temp_nwk_wq_head, nwk_wq_link, nwk_item_next) {
90 nwk_item->func(nwk_item);
91 /* nwk_item has been freed by the callback */
92 }
93 lck_mtx_lock(lck: &nwk_wq_lock);
94 }
95}
96
97__dead2
98static void
99nwk_wq_thread_func(void *v, wait_result_t w)
100{
101#pragma unused(v, w)
102 lck_mtx_lock(lck: &nwk_wq_lock);
103 (void) msleep0(chan: &nwk_wq_waitch, mtx: &nwk_wq_lock,
104 pri: (PZERO - 1), wmesg: "nwk_wq_thread_func", timo: 0, continuation: nwk_wq_thread_cont);
105 /*
106 * msleep0() shouldn't have returned as PCATCH was not set;
107 * therefore assert in this case.
108 */
109 lck_mtx_unlock(lck: &nwk_wq_lock);
110 VERIFY(0);
111}
112
113void
114nwk_wq_enqueue(struct nwk_wq_entry *nwk_item)
115{
116 lck_mtx_lock(lck: &nwk_wq_lock);
117 TAILQ_INSERT_TAIL(&nwk_wq_head, nwk_item, nwk_wq_link);
118 lck_mtx_unlock(lck: &nwk_wq_lock);
119 wakeup(chan: (caddr_t)&nwk_wq_waitch);
120}
121