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
|
/* $OpenBSD: uvm_pmemrange.h,v 1.17 2024/05/01 12:54:27 mpi Exp $ */
/*
* Copyright (c) 2009 Ariane van der Steldt <ariane@stack.nl>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* uvm_pmemrange.h: describe and manage free physical memory.
*/
#ifndef _UVM_UVM_PMEMRANGE_H_
#define _UVM_UVM_PMEMRANGE_H_
RBT_HEAD(uvm_pmr_addr, vm_page);
RBT_HEAD(uvm_pmr_size, vm_page);
/*
* Page types available:
* - DIRTY: this page may contain random data.
* - ZERO: this page has been zeroed.
*/
#define UVM_PMR_MEMTYPE_DIRTY 0
#define UVM_PMR_MEMTYPE_ZERO 1
#define UVM_PMR_MEMTYPE_MAX 2
/*
* An address range of memory.
*/
struct uvm_pmemrange {
struct uvm_pmr_addr addr; /* Free page chunks, sorted by addr. */
struct uvm_pmr_size size[UVM_PMR_MEMTYPE_MAX];
/* Free page chunks, sorted by size. */
TAILQ_HEAD(, vm_page) single[UVM_PMR_MEMTYPE_MAX];
/* single page regions (uses pageq) */
paddr_t low; /* Start of address range (pgno). */
paddr_t high; /* End +1 (pgno). */
int use; /* Use counter. */
psize_t nsegs; /* Current range count. */
TAILQ_ENTRY(uvm_pmemrange) pmr_use;
/* pmr, sorted by use */
RBT_ENTRY(uvm_pmemrange) pmr_addr;
/* pmr, sorted by address */
};
/*
* Description of failing memory allocation.
*
* Two ways new pages can become available:
* [1] page daemon drops them (we notice because they are freed)
* [2] a process calls free
*
* The buffer cache and page daemon can decide that they don't have the
* ability to make pages available in the requested range. In that case,
* the FAIL bit will be set.
* XXX There's a possibility that a page is no longer on the queues but
* XXX has not yet been freed, or that a page was busy.
* XXX Also, wired pages are not considered for paging, so they could
* XXX cause a failure that may be recoverable.
*/
struct uvm_pmalloc {
TAILQ_ENTRY(uvm_pmalloc) pmq;
/*
* Allocation request parameters.
*/
struct uvm_constraint_range pm_constraint;
psize_t pm_size;
/*
* State flags.
*/
int pm_flags;
};
/*
* uvm_pmalloc flags.
*/
#define UVM_PMA_LINKED 0x01 /* uvm_pmalloc is on list */
#define UVM_PMA_BUSY 0x02 /* entry is busy with fpageq unlocked */
#define UVM_PMA_FAIL 0x10 /* page daemon cannot free pages */
#define UVM_PMA_FREED 0x20 /* at least one page in the range was freed */
RBT_HEAD(uvm_pmemrange_addr, uvm_pmemrange);
TAILQ_HEAD(uvm_pmemrange_use, uvm_pmemrange);
/*
* pmr control structure. Contained in uvm.pmr_control.
*/
struct uvm_pmr_control {
struct uvm_pmemrange_addr addr;
struct uvm_pmemrange_use use;
/* Only changed while fpageq is locked. */
TAILQ_HEAD(, uvm_pmalloc) allocs;
};
void uvm_pmr_freepages(struct vm_page *, psize_t);
void uvm_pmr_freepageq(struct pglist *);
int uvm_pmr_getpages(psize_t, paddr_t, paddr_t, paddr_t, paddr_t,
int, int, struct pglist *);
void uvm_pmr_init(void);
int uvm_wait_pla(paddr_t, paddr_t, paddr_t, int);
void uvm_wakeup_pla(paddr_t, psize_t);
#if defined(DDB) || defined(DEBUG)
int uvm_pmr_isfree(struct vm_page *pg);
#endif
/*
* Internal tree logic.
*/
int uvm_pmr_addr_cmp(const struct vm_page *, const struct vm_page *);
int uvm_pmr_size_cmp(const struct vm_page *, const struct vm_page *);
RBT_PROTOTYPE(uvm_pmr_addr, vm_page, objt, uvm_pmr_addr_cmp);
RBT_PROTOTYPE(uvm_pmr_size, vm_page, objt, uvm_pmr_size_cmp);
RBT_PROTOTYPE(uvm_pmemrange_addr, uvm_pmemrange, pmr_addr,
uvm_pmemrange_addr_cmp);
struct vm_page *uvm_pmr_insert_addr(struct uvm_pmemrange *,
struct vm_page *, int);
void uvm_pmr_insert_size(struct uvm_pmemrange *,
struct vm_page *);
struct vm_page *uvm_pmr_insert(struct uvm_pmemrange *,
struct vm_page *, int);
void uvm_pmr_remove_addr(struct uvm_pmemrange *,
struct vm_page *);
void uvm_pmr_remove_size(struct uvm_pmemrange *,
struct vm_page *);
void uvm_pmr_remove(struct uvm_pmemrange *,
struct vm_page *);
struct vm_page *uvm_pmr_extract_range(struct uvm_pmemrange *,
struct vm_page *, paddr_t, paddr_t,
struct pglist *);
struct vm_page *uvm_pmr_cache_get(int);
void uvm_pmr_cache_put(struct vm_page *);
void uvm_pmr_cache_drain(void);
#endif /* _UVM_UVM_PMEMRANGE_H_ */
|
