2 * Copyright (c) 2010 by The DragonFly Project and Samuel J. Greear.
5 * This code is derived from software contributed to The DragonFly Project
6 * by Samuel J. Greear <sjg@thesjg.com>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 #include <sys/types.h>
37 #include <sys/kernel.h>
38 #include <sys/objcache.h>
39 #include <sys/sysctl.h>
40 #include <sys/param.h>
41 #include <sys/serialize.h>
42 #include <sys/systm.h>
44 #include <sys/queue.h>
47 #include <vm/vm_extern.h>
48 #include <vm/vm_kern.h>
49 #include <vm/vm_page.h>
50 #include <cpu/lwbuf.h>
51 #include <machine/globaldata.h>
52 #include <machine/atomic.h>
53 #include <machine/param.h>
55 #include <sys/mplock2.h>
57 static void lwbuf_init(void *);
58 SYSINIT(sock_lwb, SI_BOOT2_MACHDEP, SI_ORDER_ANY, lwbuf_init, NULL);
60 static struct objcache *lwbuf_cache;
62 MALLOC_DEFINE(M_LWBUF, "lwbuf", "Lightweight buffers");
63 struct objcache_malloc_args lwbuf_malloc_args =
64 { sizeof(struct lwbuf), M_LWBUF };
66 /* Number of pages of KVA to allocate at boot per cpu (1MB) */
67 static int lwbuf_reserve_pages = 256;
68 static int lwbuf_count;
69 static int lwbuf_kva_bytes;
71 SYSCTL_INT(_kern_ipc, OID_AUTO, lwbuf_reserve, CTLFLAG_RD,
72 &lwbuf_reserve_pages, 0,
73 "Number of pre-allocated lightweight buffers");
74 SYSCTL_INT(_kern_ipc, OID_AUTO, lwbuf_count, CTLFLAG_RD,
76 "Currently allocated lightweight buffers");
77 SYSCTL_INT(_kern_ipc, OID_AUTO, lwbuf_kva_bytes, CTLFLAG_RD,
79 "Currently used KVA for lightweight buffers");
82 lwbuf_cache_ctor(void *obj, void *pdata, int ocflags)
84 struct lwbuf *lwb = (struct lwbuf *)obj;
89 lwb->kva = kmem_alloc_nofault(&kernel_map, PAGE_SIZE, PAGE_SIZE);
93 atomic_add_int(&lwbuf_kva_bytes, PAGE_SIZE);
99 * Destructor for lwb. Note that we must remove any pmap entries
100 * created with pmap_kenter() to prevent them from being misinterpreted
101 * as managed pages which would cause kernel_pmap.pm_stats.resident_count
102 * to get out of whack.
105 lwbuf_cache_dtor(void *obj, void *pdata)
107 struct lwbuf *lwb = (struct lwbuf *)obj;
109 KKASSERT(lwb->kva != 0);
111 pmap_kremove_quick(lwb->kva);
112 kmem_free(&kernel_map, lwb->kva, PAGE_SIZE);
115 atomic_add_int(&lwbuf_kva_bytes, -PAGE_SIZE);
119 lwbuf_init(void *arg)
121 lwbuf_cache = objcache_create("lwbuf", 0, 0,
122 lwbuf_cache_ctor, lwbuf_cache_dtor, NULL,
123 objcache_malloc_alloc, objcache_malloc_free,
128 lwbuf_alloc(vm_page_t m)
130 struct mdglobaldata *gd = mdcpu;
133 lwb = objcache_get(lwbuf_cache, M_WAITOK);
134 KKASSERT(lwb->m == NULL);
136 lwb->cpumask = gd->mi.gd_cpumask;
137 pmap_kenter_quick(lwb->kva, m->phys_addr);
138 atomic_add_int(&lwbuf_count, 1);
144 lwbuf_free(struct lwbuf *lwb)
146 KKASSERT(lwb->m != NULL);
149 objcache_put(lwbuf_cache, lwb);
150 atomic_add_int(&lwbuf_count, -1);
154 lwbuf_set_global(struct lwbuf *lwb)
156 if (lwb->cpumask != (cpumask_t)-1) {
157 pmap_kenter_sync(lwb->kva);
158 lwb->cpumask = (cpumask_t)-1;
163 _lwbuf_kva(struct lwbuf *lwb, struct mdglobaldata *gd)
167 pmap_kenter_sync_quick(lwb->kva);
171 new = old | gd->mi.gd_cpumask;
172 } while (atomic_cmpset_int(&lwb->cpumask, old, new) == 0);
178 lwbuf_kva(struct lwbuf *lwb)
180 struct mdglobaldata *gd = mdcpu;
182 if (lwb->cpumask & gd->mi.gd_cpumask)
185 return (_lwbuf_kva(lwb, gd));