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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
|
/* $OpenBSD: uvm_pglist.c,v 1.10 2001/11/12 01:26:10 art Exp $ */
/* $NetBSD: uvm_pglist.c,v 1.13 2001/02/18 21:19:08 chs Exp $ */
/*-
* Copyright (c) 1997 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* uvm_pglist.c: pglist functions
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <uvm/uvm.h>
#ifdef VM_PAGE_ALLOC_MEMORY_STATS
#define STAT_INCR(v) (v)++
#define STAT_DECR(v) do { \
if ((v) == 0) \
printf("%s:%d -- Already 0!\n", __FILE__, __LINE__); \
else \
(v)--; \
} while (0)
u_long uvm_pglistalloc_npages;
#else
#define STAT_INCR(v)
#define STAT_DECR(v)
#endif
/*
* uvm_pglistalloc: allocate a list of pages
*
* => allocated pages are placed at the tail of rlist. rlist is
* assumed to be properly initialized by caller.
* => returns 0 on success or errno on failure
* => XXX: implementation allocates only a single segment, also
* might be able to better advantage of vm_physeg[].
* => doesn't take into account clean non-busy pages on inactive list
* that could be used(?)
* => params:
* size the size of the allocation, rounded to page size.
* low the low address of the allowed allocation range.
* high the high address of the allowed allocation range.
* alignment memory must be aligned to this power-of-two boundary.
* boundary no segment in the allocation may cross this
* power-of-two boundary (relative to zero).
*/
int
uvm_pglistalloc(size, low, high, alignment, boundary, rlist, nsegs, waitok)
psize_t size;
paddr_t low, high, alignment, boundary;
struct pglist *rlist;
int nsegs, waitok;
{
paddr_t try, idxpa, lastidxpa;
int psi;
struct vm_page *pgs;
int s, tryidx, idx, pgflidx, end, error, free_list;
vm_page_t m;
u_long pagemask;
#ifdef DEBUG
vm_page_t tp;
#endif
KASSERT((alignment & (alignment - 1)) == 0);
KASSERT((boundary & (boundary - 1)) == 0);
/*
* Our allocations are always page granularity, so our alignment
* must be, too.
*/
if (alignment < PAGE_SIZE)
alignment = PAGE_SIZE;
size = round_page(size);
try = roundup(low, alignment);
if (boundary != 0 && boundary < size)
return (EINVAL);
pagemask = ~(boundary - 1);
/* Default to "lose". */
error = ENOMEM;
/*
* Block all memory allocation and lock the free list.
*/
s = uvm_lock_fpageq();
/* Are there even any free pages? */
if (uvmexp.free <= (uvmexp.reserve_pagedaemon + uvmexp.reserve_kernel))
goto out;
for (;; try += alignment) {
if (try + size > high) {
/*
* We've run past the allowable range.
*/
goto out;
}
/*
* Make sure this is a managed physical page.
*/
if ((psi = vm_physseg_find(atop(try), &idx)) == -1)
continue; /* managed? */
if (vm_physseg_find(atop(try + size), NULL) != psi)
continue; /* end must be in this segment */
tryidx = idx;
end = idx + (size / PAGE_SIZE);
pgs = vm_physmem[psi].pgs;
/*
* Found a suitable starting page. See of the range is free.
*/
for (; idx < end; idx++) {
if (VM_PAGE_IS_FREE(&pgs[idx]) == 0) {
break;
}
idxpa = VM_PAGE_TO_PHYS(&pgs[idx]);
if (idx > tryidx) {
lastidxpa = VM_PAGE_TO_PHYS(&pgs[idx - 1]);
if ((lastidxpa + PAGE_SIZE) != idxpa) {
/*
* Region not contiguous.
*/
break;
}
if (boundary != 0 &&
((lastidxpa ^ idxpa) & pagemask) != 0) {
/*
* Region crosses boundary.
*/
break;
}
}
}
if (idx == end) {
break;
}
}
#if PGFL_NQUEUES != 2
#error uvm_pglistalloc needs to be updated
#endif
/*
* we have a chunk of memory that conforms to the requested constraints.
*/
idx = tryidx;
while (idx < end) {
m = &pgs[idx];
free_list = uvm_page_lookup_freelist(m);
pgflidx = (m->flags & PG_ZERO) ? PGFL_ZEROS : PGFL_UNKNOWN;
#ifdef DEBUG
for (tp = TAILQ_FIRST(&uvm.page_free[
free_list].pgfl_queues[pgflidx]);
tp != NULL;
tp = TAILQ_NEXT(tp, pageq)) {
if (tp == m)
break;
}
if (tp == NULL)
panic("uvm_pglistalloc: page not on freelist");
#endif
TAILQ_REMOVE(&uvm.page_free[free_list].pgfl_queues[pgflidx],
m, pageq);
uvmexp.free--;
if (m->flags & PG_ZERO)
uvmexp.zeropages--;
m->flags = PG_CLEAN;
m->pqflags = 0;
m->uobject = NULL;
m->uanon = NULL;
m->version++;
TAILQ_INSERT_TAIL(rlist, m, pageq);
idx++;
STAT_INCR(uvm_pglistalloc_npages);
}
error = 0;
out:
/*
* check to see if we need to generate some free pages waking
* the pagedaemon.
*/
if (uvmexp.free + uvmexp.paging < uvmexp.freemin ||
(uvmexp.free + uvmexp.paging < uvmexp.freetarg &&
uvmexp.inactive < uvmexp.inactarg)) {
wakeup(&uvm.pagedaemon);
}
uvm_unlock_fpageq(s);
return (error);
}
/*
* uvm_pglistfree: free a list of pages
*
* => pages should already be unmapped
*/
void
uvm_pglistfree(list)
struct pglist *list;
{
vm_page_t m;
int s;
/*
* Block all memory allocation and lock the free list.
*/
s = uvm_lock_fpageq();
while ((m = TAILQ_FIRST(list)) != NULL) {
KASSERT((m->pqflags & (PQ_ACTIVE|PQ_INACTIVE)) == 0);
TAILQ_REMOVE(list, m, pageq);
m->pqflags = PQ_FREE;
TAILQ_INSERT_TAIL(&uvm.page_free[
uvm_page_lookup_freelist(m)].pgfl_queues[PGFL_UNKNOWN],
m, pageq);
uvmexp.free++;
if (uvmexp.zeropages < UVM_PAGEZERO_TARGET)
uvm.page_idle_zero = vm_page_zero_enable;
STAT_DECR(uvm_pglistalloc_npages);
}
uvm_unlock_fpageq(s);
}
|
