1 /*
2  * Copyright (C) 2008 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef _PAGEMAP_PAGEMAP_H
18 #define _PAGEMAP_PAGEMAP_H
19 
20 #include <stdint.h>
21 #include <stdio.h>
22 #include <sys/cdefs.h>
23 #include <sys/types.h>
24 
25 __BEGIN_DECLS
26 
27 typedef struct pm_memusage pm_memusage_t;
28 
29 /* Holds the various metrics for memory usage of a process or a mapping. */
30 struct pm_memusage {
31     size_t vss;
32     size_t rss;
33     size_t pss;
34     size_t uss;
35     size_t swap;
36 };
37 
38 /* Clears a memusage. */
39 void pm_memusage_zero(pm_memusage_t *mu);
40 /* Adds one memusage (a) to another (b). */
41 void pm_memusage_add(pm_memusage_t *a, pm_memusage_t *b);
42 
43 typedef struct pm_kernel   pm_kernel_t;
44 typedef struct pm_process  pm_process_t;
45 typedef struct pm_map      pm_map_t;
46 
47 /* pm_kernel_t holds the state necessary to interface to the kernel's pagemap
48  * system on a global level. */
49 struct pm_kernel {
50     int kpagecount_fd;
51     int kpageflags_fd;
52 
53     int pagesize;
54 };
55 
56 /* pm_process_t holds the state necessary to interface to a particular process'
57  * pagemap. */
58 struct pm_process {
59     pm_kernel_t *ker;
60 
61     pid_t pid;
62 
63     pm_map_t **maps;
64     int num_maps;
65 
66     int pagemap_fd;
67 };
68 
69 /* pm_map_t holds the state necessary to access information about a particular
70  * mapping in a particular process. */
71 struct pm_map {
72     pm_process_t *proc;
73 
74     uint64_t start;
75     uint64_t end;
76     uint64_t offset;
77     int flags;
78 
79     char *name;
80 };
81 
82 /* Create a pm_kernel_t. */
83 int pm_kernel_create(pm_kernel_t **ker_out);
84 
85 #define pm_kernel_pagesize(ker) ((ker)->pagesize)
86 
87 /* Get a list of probably-existing PIDs (returned through *pids_out).
88  * Length of the array (in sizeof(pid_t) units) is returned through *len.
89  * The array should be freed by the caller. */
90 int pm_kernel_pids(pm_kernel_t *ker, pid_t **pids_out, size_t *len);
91 
92 /* Get the map count (from /proc/kpagecount) of a physical frame.
93  * The count is returned through *count_out. */
94 int pm_kernel_count(pm_kernel_t *ker, uint64_t pfn, uint64_t *count_out);
95 
96 /* Get the page flags (from /proc/kpageflags) of a physical frame.
97  * The count is returned through *flags_out. */
98 int pm_kernel_flags(pm_kernel_t *ker, uint64_t pfn, uint64_t *flags_out);
99 
100 #define PM_PAGE_LOCKED     (1 <<  0)
101 #define PM_PAGE_ERROR      (1 <<  1)
102 #define PM_PAGE_REFERENCED (1 <<  2)
103 #define PM_PAGE_UPTODATE   (1 <<  3)
104 #define PM_PAGE_DIRTY      (1 <<  4)
105 #define PM_PAGE_LRU        (1 <<  5)
106 #define PM_PAGE_ACTIVE     (1 <<  6)
107 #define PM_PAGE_SLAB       (1 <<  7)
108 #define PM_PAGE_WRITEBACK  (1 <<  8)
109 #define PM_PAGE_RECLAIM    (1 <<  9)
110 #define PM_PAGE_BUDDY      (1 << 10)
111 
112 /* for kernels >= 2.6.31 */
113 #define PM_PAGE_MMAP          (1 << 11)
114 #define PM_PAGE_ANON          (1 << 12)
115 #define PM_PAGE_SWAPCACHE     (1 << 13)
116 #define PM_PAGE_SWAPBACKED    (1 << 14)
117 #define PM_PAGE_COMPOUND_HEAD (1 << 15)
118 #define PM_PAGE_COMPOUND_TAIL (1 << 16)
119 #define PM_PAGE_HUGE          (1 << 17)
120 #define PM_PAGE_UNEVICTABLE   (1 << 18)
121 #define PM_PAGE_HWPOISON      (1 << 19)
122 #define PM_PAGE_NOPAGE        (1 << 20)
123 
124 /* for kernels >= 2.6.32 */
125 #define PM_PAGE_KSM           (1 << 21)
126 
127 /* for kernels >= 3.4 */
128 #define PM_PAGE_THP           (1 << 22)
129 
130 /* Destroy a pm_kernel_t. */
131 int pm_kernel_destroy(pm_kernel_t *ker);
132 
133 /* Get the PID of a pm_process_t. */
134 #define pm_process_pid(proc) ((proc)->pid)
135 
136 /* Create a pm_process_t and returns it through *proc_out.
137  * Takes a pm_kernel_t, and the PID of the process. */
138 int pm_process_create(pm_kernel_t *ker, pid_t pid, pm_process_t **proc_out);
139 
140 /* Get the total memory usage of a process and store in *usage_out. */
141 int pm_process_usage(pm_process_t *proc, pm_memusage_t *usage_out);
142 
143 /* Get the total memory usage of a process and store in *usage_out, only
144  * counting pages with specified flags. */
145 int pm_process_usage_flags(pm_process_t *proc, pm_memusage_t *usage_out,
146                         uint64_t flags_mask, uint64_t required_flags);
147 
148 /* Get the working set of a process (if ws_out != NULL), and reset it
149  * (if reset != 0). */
150 int pm_process_workingset(pm_process_t *proc, pm_memusage_t *ws_out, int reset);
151 
152 /* Get the PFNs corresponding to a range of virtual addresses.
153  * The array of PFNs is returned through *range_out, and the caller has the
154  * responsibility to free it. */
155 int pm_process_pagemap_range(pm_process_t *proc,
156                              uint64_t low, uint64_t hi,
157                              uint64_t **range_out, size_t *len);
158 
159 #define _BITS(x, offset, bits) (((x) >> offset) & ((1LL << (bits)) - 1))
160 
161 #define PM_PAGEMAP_PRESENT(x)     (_BITS(x, 63, 1))
162 #define PM_PAGEMAP_SWAPPED(x)     (_BITS(x, 62, 1))
163 #define PM_PAGEMAP_SHIFT(x)       (_BITS(x, 55, 6))
164 #define PM_PAGEMAP_PFN(x)         (_BITS(x, 0, 55))
165 #define PM_PAGEMAP_SWAP_OFFSET(x) (_BITS(x, 5, 50))
166 #define PM_PAGEMAP_SWAP_TYPE(x)   (_BITS(x, 0,  5))
167 
168 /* Get the maps in the virtual address space of this process.
169  * Returns an array of pointers to pm_map_t through *maps.
170  * The array should be freed by the caller, but the maps should not be
171  * modified or destroyed. */
172 int pm_process_maps(pm_process_t *proc, pm_map_t ***maps_out, size_t *len);
173 
174 /* Destroy a pm_process_t. */
175 int pm_process_destroy(pm_process_t *proc);
176 
177 /* Get the name, flags, start/end address, or offset of a map. */
178 #define pm_map_name(map)   ((map)->name)
179 #define pm_map_flags(map)  ((map)->flags)
180 #define PM_MAP_READ  1
181 #define PM_MAP_WRITE 2
182 #define PM_MAP_EXEC  4
183 #define PM_MAP_PERMISSIONS (PM_MAP_READ | PM_MAP_WRITE | PM_MAP_EXEC)
184 #define pm_map_start(map)  ((map)->start)
185 #define pm_map_end(map)    ((map)->end)
186 #define pm_map_offset(map) ((map)->offset)
187 
188 /* Get the PFNs of the pages in the virtual address space of this map.
189  * Array of PFNs is returned through *pagemap_out, and should be freed by the
190  * caller. */
191 int pm_map_pagemap(pm_map_t *map, uint64_t **pagemap_out, size_t *len);
192 
193 /* Get the memory usage of this map alone. */
194 int pm_map_usage(pm_map_t *map, pm_memusage_t *usage_out);
195 
196 /* Get the memory usage of this map alone, only counting pages with specified
197  * flags. */
198 int pm_map_usage_flags(pm_map_t *map, pm_memusage_t *usage_out,
199                         uint64_t flags_mask, uint64_t required_flags);
200 
201 /* Get the working set of this map alone. */
202 int pm_map_workingset(pm_map_t *map, pm_memusage_t *ws_out);
203 
204 __END_DECLS
205 
206 #endif
207