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6d80e53f AD |
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> | |
20a0307c | 9 | #include <linux/hugetlb.h> |
6d80e53f AD |
10 | #include <asm/uaccess.h> |
11 | #include "internal.h" | |
12 | ||
13 | #define KPMSIZE sizeof(u64) | |
14 | #define KPMMASK (KPMSIZE - 1) | |
ed7ce0f1 | 15 | |
6d80e53f AD |
16 | /* /proc/kpagecount - an array exposing page counts |
17 | * | |
18 | * Each entry is a u64 representing the corresponding | |
19 | * physical page count. | |
20 | */ | |
21 | static ssize_t kpagecount_read(struct file *file, char __user *buf, | |
22 | size_t count, loff_t *ppos) | |
23 | { | |
24 | u64 __user *out = (u64 __user *)buf; | |
25 | struct page *ppage; | |
26 | unsigned long src = *ppos; | |
27 | unsigned long pfn; | |
28 | ssize_t ret = 0; | |
29 | u64 pcount; | |
30 | ||
31 | pfn = src / KPMSIZE; | |
32 | count = min_t(size_t, count, (max_pfn * KPMSIZE) - src); | |
33 | if (src & KPMMASK || count & KPMMASK) | |
34 | return -EINVAL; | |
35 | ||
36 | while (count > 0) { | |
6d80e53f AD |
37 | if (pfn_valid(pfn)) |
38 | ppage = pfn_to_page(pfn); | |
ed7ce0f1 WF |
39 | else |
40 | ppage = NULL; | |
6d80e53f AD |
41 | if (!ppage) |
42 | pcount = 0; | |
43 | else | |
44 | pcount = page_mapcount(ppage); | |
45 | ||
ed7ce0f1 | 46 | if (put_user(pcount, out)) { |
6d80e53f AD |
47 | ret = -EFAULT; |
48 | break; | |
49 | } | |
50 | ||
ed7ce0f1 WF |
51 | pfn++; |
52 | out++; | |
6d80e53f AD |
53 | count -= KPMSIZE; |
54 | } | |
55 | ||
56 | *ppos += (char __user *)out - buf; | |
57 | if (!ret) | |
58 | ret = (char __user *)out - buf; | |
59 | return ret; | |
60 | } | |
61 | ||
62 | static const struct file_operations proc_kpagecount_operations = { | |
63 | .llseek = mem_lseek, | |
64 | .read = kpagecount_read, | |
65 | }; | |
66 | ||
67 | /* /proc/kpageflags - an array exposing page flags | |
68 | * | |
69 | * Each entry is a u64 representing the corresponding | |
70 | * physical page flags. | |
71 | */ | |
72 | ||
73 | /* These macros are used to decouple internal flags from exported ones */ | |
74 | ||
17797549 WF |
75 | #define KPF_LOCKED 0 |
76 | #define KPF_ERROR 1 | |
77 | #define KPF_REFERENCED 2 | |
78 | #define KPF_UPTODATE 3 | |
79 | #define KPF_DIRTY 4 | |
80 | #define KPF_LRU 5 | |
81 | #define KPF_ACTIVE 6 | |
82 | #define KPF_SLAB 7 | |
83 | #define KPF_WRITEBACK 8 | |
84 | #define KPF_RECLAIM 9 | |
85 | #define KPF_BUDDY 10 | |
86 | ||
87 | /* 11-20: new additions in 2.6.31 */ | |
88 | #define KPF_MMAP 11 | |
89 | #define KPF_ANON 12 | |
90 | #define KPF_SWAPCACHE 13 | |
91 | #define KPF_SWAPBACKED 14 | |
92 | #define KPF_COMPOUND_HEAD 15 | |
93 | #define KPF_COMPOUND_TAIL 16 | |
94 | #define KPF_HUGE 17 | |
95 | #define KPF_UNEVICTABLE 18 | |
96 | #define KPF_NOPAGE 20 | |
97 | ||
98 | /* kernel hacking assistances | |
99 | * WARNING: subject to change, never rely on them! | |
100 | */ | |
101 | #define KPF_RESERVED 32 | |
102 | #define KPF_MLOCKED 33 | |
103 | #define KPF_MAPPEDTODISK 34 | |
104 | #define KPF_PRIVATE 35 | |
105 | #define KPF_PRIVATE_2 36 | |
106 | #define KPF_OWNER_PRIVATE 37 | |
107 | #define KPF_ARCH 38 | |
108 | #define KPF_UNCACHED 39 | |
109 | ||
110 | static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit) | |
111 | { | |
112 | return ((kflags >> kbit) & 1) << ubit; | |
113 | } | |
114 | ||
115 | static u64 get_uflags(struct page *page) | |
116 | { | |
117 | u64 k; | |
118 | u64 u; | |
119 | ||
120 | /* | |
121 | * pseudo flag: KPF_NOPAGE | |
122 | * it differentiates a memory hole from a page with no flags | |
123 | */ | |
124 | if (!page) | |
125 | return 1 << KPF_NOPAGE; | |
126 | ||
127 | k = page->flags; | |
128 | u = 0; | |
129 | ||
130 | /* | |
131 | * pseudo flags for the well known (anonymous) memory mapped pages | |
132 | * | |
133 | * Note that page->_mapcount is overloaded in SLOB/SLUB/SLQB, so the | |
134 | * simple test in page_mapped() is not enough. | |
135 | */ | |
136 | if (!PageSlab(page) && page_mapped(page)) | |
137 | u |= 1 << KPF_MMAP; | |
138 | if (PageAnon(page)) | |
139 | u |= 1 << KPF_ANON; | |
140 | ||
141 | /* | |
142 | * compound pages: export both head/tail info | |
143 | * they together define a compound page's start/end pos and order | |
144 | */ | |
145 | if (PageHead(page)) | |
146 | u |= 1 << KPF_COMPOUND_HEAD; | |
147 | if (PageTail(page)) | |
148 | u |= 1 << KPF_COMPOUND_TAIL; | |
149 | if (PageHuge(page)) | |
150 | u |= 1 << KPF_HUGE; | |
151 | ||
152 | u |= kpf_copy_bit(k, KPF_LOCKED, PG_locked); | |
153 | ||
154 | /* | |
155 | * Caveats on high order pages: | |
156 | * PG_buddy will only be set on the head page; SLUB/SLQB do the same | |
157 | * for PG_slab; SLOB won't set PG_slab at all on compound pages. | |
158 | */ | |
159 | u |= kpf_copy_bit(k, KPF_SLAB, PG_slab); | |
160 | u |= kpf_copy_bit(k, KPF_BUDDY, PG_buddy); | |
161 | ||
162 | u |= kpf_copy_bit(k, KPF_ERROR, PG_error); | |
163 | u |= kpf_copy_bit(k, KPF_DIRTY, PG_dirty); | |
164 | u |= kpf_copy_bit(k, KPF_UPTODATE, PG_uptodate); | |
165 | u |= kpf_copy_bit(k, KPF_WRITEBACK, PG_writeback); | |
166 | ||
167 | u |= kpf_copy_bit(k, KPF_LRU, PG_lru); | |
168 | u |= kpf_copy_bit(k, KPF_REFERENCED, PG_referenced); | |
169 | u |= kpf_copy_bit(k, KPF_ACTIVE, PG_active); | |
170 | u |= kpf_copy_bit(k, KPF_RECLAIM, PG_reclaim); | |
171 | ||
172 | u |= kpf_copy_bit(k, KPF_SWAPCACHE, PG_swapcache); | |
173 | u |= kpf_copy_bit(k, KPF_SWAPBACKED, PG_swapbacked); | |
174 | ||
17797549 WF |
175 | u |= kpf_copy_bit(k, KPF_UNEVICTABLE, PG_unevictable); |
176 | u |= kpf_copy_bit(k, KPF_MLOCKED, PG_mlocked); | |
17797549 WF |
177 | |
178 | #ifdef CONFIG_IA64_UNCACHED_ALLOCATOR | |
179 | u |= kpf_copy_bit(k, KPF_UNCACHED, PG_uncached); | |
180 | #endif | |
181 | ||
182 | u |= kpf_copy_bit(k, KPF_RESERVED, PG_reserved); | |
183 | u |= kpf_copy_bit(k, KPF_MAPPEDTODISK, PG_mappedtodisk); | |
184 | u |= kpf_copy_bit(k, KPF_PRIVATE, PG_private); | |
185 | u |= kpf_copy_bit(k, KPF_PRIVATE_2, PG_private_2); | |
186 | u |= kpf_copy_bit(k, KPF_OWNER_PRIVATE, PG_owner_priv_1); | |
187 | u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1); | |
188 | ||
189 | return u; | |
190 | }; | |
6d80e53f AD |
191 | |
192 | static ssize_t kpageflags_read(struct file *file, char __user *buf, | |
193 | size_t count, loff_t *ppos) | |
194 | { | |
195 | u64 __user *out = (u64 __user *)buf; | |
196 | struct page *ppage; | |
197 | unsigned long src = *ppos; | |
198 | unsigned long pfn; | |
199 | ssize_t ret = 0; | |
6d80e53f AD |
200 | |
201 | pfn = src / KPMSIZE; | |
202 | count = min_t(unsigned long, count, (max_pfn * KPMSIZE) - src); | |
203 | if (src & KPMMASK || count & KPMMASK) | |
204 | return -EINVAL; | |
205 | ||
206 | while (count > 0) { | |
6d80e53f AD |
207 | if (pfn_valid(pfn)) |
208 | ppage = pfn_to_page(pfn); | |
ed7ce0f1 WF |
209 | else |
210 | ppage = NULL; | |
17797549 WF |
211 | |
212 | if (put_user(get_uflags(ppage), out)) { | |
6d80e53f AD |
213 | ret = -EFAULT; |
214 | break; | |
215 | } | |
216 | ||
ed7ce0f1 WF |
217 | pfn++; |
218 | out++; | |
6d80e53f AD |
219 | count -= KPMSIZE; |
220 | } | |
221 | ||
222 | *ppos += (char __user *)out - buf; | |
223 | if (!ret) | |
224 | ret = (char __user *)out - buf; | |
225 | return ret; | |
226 | } | |
227 | ||
228 | static const struct file_operations proc_kpageflags_operations = { | |
229 | .llseek = mem_lseek, | |
230 | .read = kpageflags_read, | |
231 | }; | |
232 | ||
233 | static int __init proc_page_init(void) | |
234 | { | |
235 | proc_create("kpagecount", S_IRUSR, NULL, &proc_kpagecount_operations); | |
236 | proc_create("kpageflags", S_IRUSR, NULL, &proc_kpageflags_operations); | |
237 | return 0; | |
238 | } | |
239 | module_init(proc_page_init); |