1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/**
* @file
*
* @ingroup rtems_bsd_rtems
*
* @brief TODO.
*/
/*
* Copyright (c) 2020 Chris Johns <chris@contemporary.software>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <machine/rtems-bsd-kernel-space.h>
#include <sys/param.h>
#include <sys/buf.h>
#include <sys/kernel.h>
#include <sys/vmem.h>
#include <vm/vm.h>
#include <vm/uma.h>
#include <vm/vm_extern.h>
#define B_MAXPHYS 0x00200000 /* nitems(b_pages[]) = atop(MAXPHYS). */
#define PBUF_PAGES (atop(maxphys) + 1)
#define MAXPHYS (128 * 1024)
#define NSWBUF_MIN 16
static u_long maxphys; /* max raw I/O transfer size */
static int nswbuf_max;
vmem_t *kernel_arena;
uma_zone_t pbuf_zone;
uma_zone_t ncl_pbuf_zone;
vm_offset_t
kva_alloc(vm_size_t size)
{
vm_offset_t addr;
size = round_page(size);
if (vmem_alloc(kernel_arena, size, M_BESTFIT | M_NOWAIT, &addr))
return (0);
return (addr);
}
static int
pbuf_ctor(void *mem, int size, void *arg, int flags)
{
struct buf *bp = mem;
bp->b_vp = NULL;
bp->b_bufobj = NULL;
/* copied from initpbuf() */
bp->b_rcred = NOCRED;
bp->b_wcred = NOCRED;
bp->b_qindex = 0; /* On no queue (QUEUE_NONE) */
bp->b_data = bp->b_kvabase;
bp->b_xflags = 0;
bp->b_flags = B_MAXPHYS;
bp->b_ioflags = 0;
bp->b_iodone = NULL;
bp->b_error = 0;
BUF_LOCK(bp, LK_EXCLUSIVE, NULL);
return (0);
}
static void
pbuf_dtor(void *mem, int size, void *arg)
{
struct buf *bp = mem;
if (bp->b_rcred != NOCRED) {
crfree(bp->b_rcred);
bp->b_rcred = NOCRED;
}
if (bp->b_wcred != NOCRED) {
crfree(bp->b_wcred);
bp->b_wcred = NOCRED;
}
BUF_UNLOCK(bp);
}
static int
pbuf_init(void *mem, int size, int flags)
{
struct buf *bp = mem;
bp->b_kvabase = (void *)kva_alloc(ptoa(PBUF_PAGES));
if (bp->b_kvabase == NULL)
return (ENOMEM);
bp->b_kvasize = ptoa(PBUF_PAGES);
BUF_LOCKINIT(bp);
LIST_INIT(&bp->b_dep);
bp->b_rcred = bp->b_wcred = NOCRED;
bp->b_xflags = 0;
return (0);
}
void
vm_pager_bufferinit(void)
{
/* Main zone for paging bufs. */
pbuf_zone = uma_zcreate("pbuf",
sizeof(struct buf) + PBUF_PAGES * sizeof(vm_page_t), pbuf_ctor,
pbuf_dtor, pbuf_init, NULL, UMA_ALIGN_CACHE, UMA_ZONE_NOFREE);
/* Few systems may still use this zone directly, so it needs a limit. */
nswbuf_max += uma_zone_set_max(pbuf_zone, NSWBUF_MIN);
}
uma_zone_t
pbuf_zsecond_create(char *name, int max)
{
uma_zone_t zone;
zone = uma_zsecond_create(
name, pbuf_ctor, pbuf_dtor, NULL, NULL, pbuf_zone);
/*
* uma_prealloc() rounds up to items per slab. If we would prealloc
* immediately on every pbuf_zsecond_create(), we may accumulate too
* much of difference between hard limit and prealloced items, which
* means wasted memory.
*/
if (nswbuf_max > 0)
nswbuf_max += uma_zone_set_max(zone, max);
else
uma_prealloc(pbuf_zone, uma_zone_set_max(zone, max));
return (zone);
}
struct buf *
getpbuf(int *pfreecnt)
{
(void)pfreecnt;
return uma_zalloc(ncl_pbuf_zone, M_WAITOK);
}
void
relpbuf(struct buf *bp, int *pfreecnt)
{
(void)pfreecnt;
uma_zfree(ncl_pbuf_zone, bp);
}
|
