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1#include <linux/bootmem.h>
2#include <linux/compiler.h>
3#include <linux/fs.h>
4#include <linux/init.h>
5#include <linux/ksm.h>
6#include <linux/mm.h>
7#include <linux/mmzone.h>
8#include <linux/proc_fs.h>
9#include <linux/seq_file.h>
10#include <linux/hugetlb.h>
11#include <linux/kernel-page-flags.h>
12#include <asm/uaccess.h>
13#include "internal.h"
14
15#define KPMSIZE sizeof(u64)
16#define KPMMASK (KPMSIZE - 1)
17
18/* /proc/kpagecount - an array exposing page counts
19 *
20 * Each entry is a u64 representing the corresponding
21 * physical page count.
22 */
23static ssize_t kpagecount_read(struct file *file, char __user *buf,
24 size_t count, loff_t *ppos)
25{
26 u64 __user *out = (u64 __user *)buf;
27 struct page *ppage;
28 unsigned long src = *ppos;
29 unsigned long pfn;
30 ssize_t ret = 0;
31 u64 pcount;
32
33 pfn = src / KPMSIZE;
34 count = min_t(size_t, count, (max_pfn * KPMSIZE) - src);
35 if (src & KPMMASK || count & KPMMASK)
36 return -EINVAL;
37
38 while (count > 0) {
39 if (pfn_valid(pfn))
40 ppage = pfn_to_page(pfn);
41 else
42 ppage = NULL;
43 if (!ppage || PageSlab(ppage))
44 pcount = 0;
45 else
46 pcount = page_mapcount(ppage);
47
48 if (put_user(pcount, out)) {
49 ret = -EFAULT;
50 break;
51 }
52
53 pfn++;
54 out++;
55 count -= KPMSIZE;
56 }
57
58 *ppos += (char __user *)out - buf;
59 if (!ret)
60 ret = (char __user *)out - buf;
61 return ret;
62}
63
64static const struct file_operations proc_kpagecount_operations = {
65 .llseek = mem_lseek,
66 .read = kpagecount_read,
67};
68
69/* /proc/kpageflags - an array exposing page flags
70 *
71 * Each entry is a u64 representing the corresponding
72 * physical page flags.
73 */
74
75static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit)
76{
77 return ((kflags >> kbit) & 1) << ubit;
78}
79
80u64 stable_page_flags(struct page *page)
81{
82 u64 k;
83 u64 u;
84
85 /*
86 * pseudo flag: KPF_NOPAGE
87 * it differentiates a memory hole from a page with no flags
88 */
89 if (!page)
90 return 1 << KPF_NOPAGE;
91
92 k = page->flags;
93 u = 0;
94
95 /*
96 * pseudo flags for the well known (anonymous) memory mapped pages
97 *
98 * Note that page->_mapcount is overloaded in SLOB/SLUB/SLQB, so the
99 * simple test in page_mapped() is not enough.
100 */
101 if (!PageSlab(page) && page_mapped(page))
102 u |= 1 << KPF_MMAP;
103 if (PageAnon(page))
104 u |= 1 << KPF_ANON;
105 if (PageKsm(page))
106 u |= 1 << KPF_KSM;
107
108 /*
109 * compound pages: export both head/tail info
110 * they together define a compound page's start/end pos and order
111 */
112 if (PageHead(page))
113 u |= 1 << KPF_COMPOUND_HEAD;
114 if (PageTail(page))
115 u |= 1 << KPF_COMPOUND_TAIL;
116 if (PageHuge(page))
117 u |= 1 << KPF_HUGE;
118
119 /*
120 * Caveats on high order pages: page->_count will only be set
121 * -1 on the head page; SLUB/SLQB do the same for PG_slab;
122 * SLOB won't set PG_slab at all on compound pages.
123 */
124 if (PageBuddy(page))
125 u |= 1 << KPF_BUDDY;
126
127 u |= kpf_copy_bit(k, KPF_LOCKED, PG_locked);
128
129 u |= kpf_copy_bit(k, KPF_SLAB, PG_slab);
130
131 u |= kpf_copy_bit(k, KPF_ERROR, PG_error);
132 u |= kpf_copy_bit(k, KPF_DIRTY, PG_dirty);
133 u |= kpf_copy_bit(k, KPF_UPTODATE, PG_uptodate);
134 u |= kpf_copy_bit(k, KPF_WRITEBACK, PG_writeback);
135
136 u |= kpf_copy_bit(k, KPF_LRU, PG_lru);
137 u |= kpf_copy_bit(k, KPF_REFERENCED, PG_referenced);
138 u |= kpf_copy_bit(k, KPF_ACTIVE, PG_active);
139 u |= kpf_copy_bit(k, KPF_RECLAIM, PG_reclaim);
140
141 u |= kpf_copy_bit(k, KPF_SWAPCACHE, PG_swapcache);
142 u |= kpf_copy_bit(k, KPF_SWAPBACKED, PG_swapbacked);
143
144 u |= kpf_copy_bit(k, KPF_UNEVICTABLE, PG_unevictable);
145 u |= kpf_copy_bit(k, KPF_MLOCKED, PG_mlocked);
146
147#ifdef CONFIG_MEMORY_FAILURE
148 u |= kpf_copy_bit(k, KPF_HWPOISON, PG_hwpoison);
149#endif
150
151#ifdef CONFIG_ARCH_USES_PG_UNCACHED
152 u |= kpf_copy_bit(k, KPF_UNCACHED, PG_uncached);
153#endif
154
155 u |= kpf_copy_bit(k, KPF_RESERVED, PG_reserved);
156 u |= kpf_copy_bit(k, KPF_MAPPEDTODISK, PG_mappedtodisk);
157 u |= kpf_copy_bit(k, KPF_PRIVATE, PG_private);
158 u |= kpf_copy_bit(k, KPF_PRIVATE_2, PG_private_2);
159 u |= kpf_copy_bit(k, KPF_OWNER_PRIVATE, PG_owner_priv_1);
160 u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1);
161
162 return u;
163};
164
165static ssize_t kpageflags_read(struct file *file, char __user *buf,
166 size_t count, loff_t *ppos)
167{
168 u64 __user *out = (u64 __user *)buf;
169 struct page *ppage;
170 unsigned long src = *ppos;
171 unsigned long pfn;
172 ssize_t ret = 0;
173
174 pfn = src / KPMSIZE;
175 count = min_t(unsigned long, count, (max_pfn * KPMSIZE) - src);
176 if (src & KPMMASK || count & KPMMASK)
177 return -EINVAL;
178
179 while (count > 0) {
180 if (pfn_valid(pfn))
181 ppage = pfn_to_page(pfn);
182 else
183 ppage = NULL;
184
185 if (put_user(stable_page_flags(ppage), out)) {
186 ret = -EFAULT;
187 break;
188 }
189
190 pfn++;
191 out++;
192 count -= KPMSIZE;
193 }
194
195 *ppos += (char __user *)out - buf;
196 if (!ret)
197 ret = (char __user *)out - buf;
198 return ret;
199}
200
201static const struct file_operations proc_kpageflags_operations = {
202 .llseek = mem_lseek,
203 .read = kpageflags_read,
204};
205
206static int __init proc_page_init(void)
207{
208 proc_create("kpagecount", S_IRUSR, NULL, &proc_kpagecount_operations);
209 proc_create("kpageflags", S_IRUSR, NULL, &proc_kpageflags_operations);
210 return 0;
211}
212module_init(proc_page_init);
1#include <linux/bootmem.h>
2#include <linux/compiler.h>
3#include <linux/fs.h>
4#include <linux/init.h>
5#include <linux/ksm.h>
6#include <linux/mm.h>
7#include <linux/mmzone.h>
8#include <linux/proc_fs.h>
9#include <linux/seq_file.h>
10#include <linux/hugetlb.h>
11#include <linux/kernel-page-flags.h>
12#include <asm/uaccess.h>
13#include "internal.h"
14
15#define KPMSIZE sizeof(u64)
16#define KPMMASK (KPMSIZE - 1)
17
18/* /proc/kpagecount - an array exposing page counts
19 *
20 * Each entry is a u64 representing the corresponding
21 * physical page count.
22 */
23static ssize_t kpagecount_read(struct file *file, char __user *buf,
24 size_t count, loff_t *ppos)
25{
26 u64 __user *out = (u64 __user *)buf;
27 struct page *ppage;
28 unsigned long src = *ppos;
29 unsigned long pfn;
30 ssize_t ret = 0;
31 u64 pcount;
32
33 pfn = src / KPMSIZE;
34 count = min_t(size_t, count, (max_pfn * KPMSIZE) - src);
35 if (src & KPMMASK || count & KPMMASK)
36 return -EINVAL;
37
38 while (count > 0) {
39 if (pfn_valid(pfn))
40 ppage = pfn_to_page(pfn);
41 else
42 ppage = NULL;
43 if (!ppage || PageSlab(ppage))
44 pcount = 0;
45 else
46 pcount = page_mapcount(ppage);
47
48 if (put_user(pcount, out)) {
49 ret = -EFAULT;
50 break;
51 }
52
53 pfn++;
54 out++;
55 count -= KPMSIZE;
56 }
57
58 *ppos += (char __user *)out - buf;
59 if (!ret)
60 ret = (char __user *)out - buf;
61 return ret;
62}
63
64static const struct file_operations proc_kpagecount_operations = {
65 .llseek = mem_lseek,
66 .read = kpagecount_read,
67};
68
69/* /proc/kpageflags - an array exposing page flags
70 *
71 * Each entry is a u64 representing the corresponding
72 * physical page flags.
73 */
74
75static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit)
76{
77 return ((kflags >> kbit) & 1) << ubit;
78}
79
80u64 stable_page_flags(struct page *page)
81{
82 u64 k;
83 u64 u;
84
85 /*
86 * pseudo flag: KPF_NOPAGE
87 * it differentiates a memory hole from a page with no flags
88 */
89 if (!page)
90 return 1 << KPF_NOPAGE;
91
92 k = page->flags;
93 u = 0;
94
95 /*
96 * pseudo flags for the well known (anonymous) memory mapped pages
97 *
98 * Note that page->_mapcount is overloaded in SLOB/SLUB/SLQB, so the
99 * simple test in page_mapped() is not enough.
100 */
101 if (!PageSlab(page) && page_mapped(page))
102 u |= 1 << KPF_MMAP;
103 if (PageAnon(page))
104 u |= 1 << KPF_ANON;
105 if (PageKsm(page))
106 u |= 1 << KPF_KSM;
107
108 /*
109 * compound pages: export both head/tail info
110 * they together define a compound page's start/end pos and order
111 */
112 if (PageHead(page))
113 u |= 1 << KPF_COMPOUND_HEAD;
114 if (PageTail(page))
115 u |= 1 << KPF_COMPOUND_TAIL;
116 if (PageHuge(page))
117 u |= 1 << KPF_HUGE;
118 else if (PageTransCompound(page))
119 u |= 1 << KPF_THP;
120
121 /*
122 * Caveats on high order pages: page->_count will only be set
123 * -1 on the head page; SLUB/SLQB do the same for PG_slab;
124 * SLOB won't set PG_slab at all on compound pages.
125 */
126 if (PageBuddy(page))
127 u |= 1 << KPF_BUDDY;
128
129 u |= kpf_copy_bit(k, KPF_LOCKED, PG_locked);
130
131 u |= kpf_copy_bit(k, KPF_SLAB, PG_slab);
132
133 u |= kpf_copy_bit(k, KPF_ERROR, PG_error);
134 u |= kpf_copy_bit(k, KPF_DIRTY, PG_dirty);
135 u |= kpf_copy_bit(k, KPF_UPTODATE, PG_uptodate);
136 u |= kpf_copy_bit(k, KPF_WRITEBACK, PG_writeback);
137
138 u |= kpf_copy_bit(k, KPF_LRU, PG_lru);
139 u |= kpf_copy_bit(k, KPF_REFERENCED, PG_referenced);
140 u |= kpf_copy_bit(k, KPF_ACTIVE, PG_active);
141 u |= kpf_copy_bit(k, KPF_RECLAIM, PG_reclaim);
142
143 u |= kpf_copy_bit(k, KPF_SWAPCACHE, PG_swapcache);
144 u |= kpf_copy_bit(k, KPF_SWAPBACKED, PG_swapbacked);
145
146 u |= kpf_copy_bit(k, KPF_UNEVICTABLE, PG_unevictable);
147 u |= kpf_copy_bit(k, KPF_MLOCKED, PG_mlocked);
148
149#ifdef CONFIG_MEMORY_FAILURE
150 u |= kpf_copy_bit(k, KPF_HWPOISON, PG_hwpoison);
151#endif
152
153#ifdef CONFIG_ARCH_USES_PG_UNCACHED
154 u |= kpf_copy_bit(k, KPF_UNCACHED, PG_uncached);
155#endif
156
157 u |= kpf_copy_bit(k, KPF_RESERVED, PG_reserved);
158 u |= kpf_copy_bit(k, KPF_MAPPEDTODISK, PG_mappedtodisk);
159 u |= kpf_copy_bit(k, KPF_PRIVATE, PG_private);
160 u |= kpf_copy_bit(k, KPF_PRIVATE_2, PG_private_2);
161 u |= kpf_copy_bit(k, KPF_OWNER_PRIVATE, PG_owner_priv_1);
162 u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1);
163
164 return u;
165};
166
167static ssize_t kpageflags_read(struct file *file, char __user *buf,
168 size_t count, loff_t *ppos)
169{
170 u64 __user *out = (u64 __user *)buf;
171 struct page *ppage;
172 unsigned long src = *ppos;
173 unsigned long pfn;
174 ssize_t ret = 0;
175
176 pfn = src / KPMSIZE;
177 count = min_t(unsigned long, count, (max_pfn * KPMSIZE) - src);
178 if (src & KPMMASK || count & KPMMASK)
179 return -EINVAL;
180
181 while (count > 0) {
182 if (pfn_valid(pfn))
183 ppage = pfn_to_page(pfn);
184 else
185 ppage = NULL;
186
187 if (put_user(stable_page_flags(ppage), out)) {
188 ret = -EFAULT;
189 break;
190 }
191
192 pfn++;
193 out++;
194 count -= KPMSIZE;
195 }
196
197 *ppos += (char __user *)out - buf;
198 if (!ret)
199 ret = (char __user *)out - buf;
200 return ret;
201}
202
203static const struct file_operations proc_kpageflags_operations = {
204 .llseek = mem_lseek,
205 .read = kpageflags_read,
206};
207
208static int __init proc_page_init(void)
209{
210 proc_create("kpagecount", S_IRUSR, NULL, &proc_kpagecount_operations);
211 proc_create("kpageflags", S_IRUSR, NULL, &proc_kpageflags_operations);
212 return 0;
213}
214module_init(proc_page_init);