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review.evervolv.com / android_kernel_htc_msm8960 / c9e27d94f5fc726f88897914025619fbfc18b23c / . / fs / proc / page.c
blob: 767d95a6d1b1bfdd713226915fb20bcca921347d [file] [log] [blame]
Alexey Dobriyan6d80e532008-10-06 14:26:12 +0400[diff] [blame]1#include <linux/bootmem.h>
2#include <linux/compiler.h>
3#include <linux/fs.h>
4#include <linux/init.h>
5#include <linux/mm.h>
6#include <linux/mmzone.h>
7#include <linux/proc_fs.h>
8#include <linux/seq_file.h>
9#include <asm/uaccess.h>
10#include "internal.h"
11
12#define KPMSIZE sizeof(u64)
13#define KPMMASK (KPMSIZE - 1)
14/* /proc/kpagecount - an array exposing page counts
15 *
16 * Each entry is a u64 representing the corresponding
17 * physical page count.
18 */
19static ssize_t kpagecount_read(struct file *file, char __user *buf,
20 size_t count, loff_t *ppos)
21{
22 u64 __user *out = (u64 __user *)buf;
23 struct page *ppage;
24 unsigned long src = *ppos;
25 unsigned long pfn;
26 ssize_t ret = 0;
27 u64 pcount;
28
29 pfn = src / KPMSIZE;
30 count = min_t(size_t, count, (max_pfn * KPMSIZE) - src);
31 if (src & KPMMASK || count & KPMMASK)
32 return -EINVAL;
33
34 while (count > 0) {
35 ppage = NULL;
36 if (pfn_valid(pfn))
37 ppage = pfn_to_page(pfn);
38 pfn++;
39 if (!ppage)
40 pcount = 0;
41 else
42 pcount = page_mapcount(ppage);
43
44 if (put_user(pcount, out++)) {
45 ret = -EFAULT;
46 break;
47 }
48
49 count -= KPMSIZE;
50 }
51
52 *ppos += (char __user *)out - buf;
53 if (!ret)
54 ret = (char __user *)out - buf;
55 return ret;
56}
57
58static const struct file_operations proc_kpagecount_operations = {
59 .llseek = mem_lseek,
60 .read = kpagecount_read,
61};
62
63/* /proc/kpageflags - an array exposing page flags
64 *
65 * Each entry is a u64 representing the corresponding
66 * physical page flags.
67 */
68
69/* These macros are used to decouple internal flags from exported ones */
70
71#define KPF_LOCKED 0
72#define KPF_ERROR 1
73#define KPF_REFERENCED 2
74#define KPF_UPTODATE 3
75#define KPF_DIRTY 4
76#define KPF_LRU 5
77#define KPF_ACTIVE 6
78#define KPF_SLAB 7
79#define KPF_WRITEBACK 8
80#define KPF_RECLAIM 9
81#define KPF_BUDDY 10
82
83#define kpf_copy_bit(flags, srcpos, dstpos) (((flags >> srcpos) & 1) << dstpos)
84
85static ssize_t kpageflags_read(struct file *file, char __user *buf,
86 size_t count, loff_t *ppos)
87{
88 u64 __user *out = (u64 __user *)buf;
89 struct page *ppage;
90 unsigned long src = *ppos;
91 unsigned long pfn;
92 ssize_t ret = 0;
93 u64 kflags, uflags;
94
95 pfn = src / KPMSIZE;
96 count = min_t(unsigned long, count, (max_pfn * KPMSIZE) - src);
97 if (src & KPMMASK || count & KPMMASK)
98 return -EINVAL;
99
100 while (count > 0) {
101 ppage = NULL;
102 if (pfn_valid(pfn))
103 ppage = pfn_to_page(pfn);
104 pfn++;
105 if (!ppage)
106 kflags = 0;
107 else
108 kflags = ppage->flags;
109
110 uflags = kpf_copy_bit(KPF_LOCKED, PG_locked, kflags) |
111 kpf_copy_bit(kflags, KPF_ERROR, PG_error) |
112 kpf_copy_bit(kflags, KPF_REFERENCED, PG_referenced) |
113 kpf_copy_bit(kflags, KPF_UPTODATE, PG_uptodate) |
114 kpf_copy_bit(kflags, KPF_DIRTY, PG_dirty) |
115 kpf_copy_bit(kflags, KPF_LRU, PG_lru) |
116 kpf_copy_bit(kflags, KPF_ACTIVE, PG_active) |
117 kpf_copy_bit(kflags, KPF_SLAB, PG_slab) |
118 kpf_copy_bit(kflags, KPF_WRITEBACK, PG_writeback) |
119 kpf_copy_bit(kflags, KPF_RECLAIM, PG_reclaim) |
120 kpf_copy_bit(kflags, KPF_BUDDY, PG_buddy);
121
122 if (put_user(uflags, out++)) {
123 ret = -EFAULT;
124 break;
125 }
126
127 count -= KPMSIZE;
128 }
129
130 *ppos += (char __user *)out - buf;
131 if (!ret)
132 ret = (char __user *)out - buf;
133 return ret;
134}
135
136static const struct file_operations proc_kpageflags_operations = {
137 .llseek = mem_lseek,
138 .read = kpageflags_read,
139};
140
141static int __init proc_page_init(void)
142{
143 proc_create("kpagecount", S_IRUSR, NULL, &proc_kpagecount_operations);
144 proc_create("kpageflags", S_IRUSR, NULL, &proc_kpageflags_operations);
145 return 0;
146}
147module_init(proc_page_init);