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Arjan van de Ven926e5392008-04-17 17:40:45 +02001/*
2 * Debug helper to dump the current kernel pagetables of the system
3 * so that we can see what the various memory ranges are set to.
4 *
5 * (C) Copyright 2008 Intel Corporation
6 *
7 * Author: Arjan van de Ven <arjan@linux.intel.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; version 2
12 * of the License.
13 */
14
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020015#include <linux/debugfs.h>
16#include <linux/mm.h>
Arjan van de Ven926e5392008-04-17 17:40:45 +020017#include <linux/module.h>
18#include <linux/seq_file.h>
Arjan van de Ven926e5392008-04-17 17:40:45 +020019
20#include <asm/pgtable.h>
21
22/*
23 * The dumper groups pagetable entries of the same type into one, and for
24 * that it needs to keep some state when walking, and flush this state
25 * when a "break" in the continuity is found.
26 */
27struct pg_state {
28 int level;
29 pgprot_t current_prot;
30 unsigned long start_address;
31 unsigned long current_address;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020032 const struct addr_marker *marker;
H. Peter Anvin3891a042014-04-29 16:46:09 -070033 unsigned long lines;
Borislav Petkovef6bea62014-01-18 12:48:14 +010034 bool to_dmesg;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020035};
36
37struct addr_marker {
38 unsigned long start_address;
39 const char *name;
H. Peter Anvin3891a042014-04-29 16:46:09 -070040 unsigned long max_lines;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020041};
42
Andres Salomon92851e22010-07-20 15:19:46 -070043/* indices for address_markers; keep sync'd w/ address_markers below */
44enum address_markers_idx {
45 USER_SPACE_NR = 0,
46#ifdef CONFIG_X86_64
47 KERNEL_SPACE_NR,
48 LOW_KERNEL_NR,
49 VMALLOC_START_NR,
50 VMEMMAP_START_NR,
Mathias Krause8a5a5d12014-09-07 20:30:29 +020051# ifdef CONFIG_X86_ESPFIX64
H. Peter Anvin3891a042014-04-29 16:46:09 -070052 ESPFIX_START_NR,
Mathias Krause8a5a5d12014-09-07 20:30:29 +020053# endif
Andres Salomon92851e22010-07-20 15:19:46 -070054 HIGH_KERNEL_NR,
55 MODULES_VADDR_NR,
56 MODULES_END_NR,
57#else
58 KERNEL_SPACE_NR,
59 VMALLOC_START_NR,
60 VMALLOC_END_NR,
61# ifdef CONFIG_HIGHMEM
62 PKMAP_BASE_NR,
63# endif
64 FIXADDR_START_NR,
65#endif
66};
67
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020068/* Address space markers hints */
69static struct addr_marker address_markers[] = {
70 { 0, "User Space" },
71#ifdef CONFIG_X86_64
72 { 0x8000000000000000UL, "Kernel Space" },
Jiri Slaby684eb012008-05-12 15:43:37 +020073 { PAGE_OFFSET, "Low Kernel Mapping" },
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020074 { VMALLOC_START, "vmalloc() Area" },
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020075 { VMEMMAP_START, "Vmemmap" },
Mathias Krause8a5a5d12014-09-07 20:30:29 +020076# ifdef CONFIG_X86_ESPFIX64
H. Peter Anvin3891a042014-04-29 16:46:09 -070077 { ESPFIX_BASE_ADDR, "ESPfix Area", 16 },
Mathias Krause8a5a5d12014-09-07 20:30:29 +020078# endif
Mathias Krause8266e312014-09-21 17:26:54 +020079# ifdef CONFIG_EFI
80 { EFI_VA_END, "EFI Runtime Services" },
81# endif
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020082 { __START_KERNEL_map, "High Kernel Mapping" },
Yinghai Lu9a79cf92008-03-07 19:17:55 -080083 { MODULES_VADDR, "Modules" },
84 { MODULES_END, "End Modules" },
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020085#else
86 { PAGE_OFFSET, "Kernel Mapping" },
87 { 0/* VMALLOC_START */, "vmalloc() Area" },
88 { 0/*VMALLOC_END*/, "vmalloc() End" },
89# ifdef CONFIG_HIGHMEM
90 { 0/*PKMAP_BASE*/, "Persisent kmap() Area" },
91# endif
92 { 0/*FIXADDR_START*/, "Fixmap Area" },
93#endif
94 { -1, NULL } /* End of list */
Arjan van de Ven926e5392008-04-17 17:40:45 +020095};
96
97/* Multipliers for offsets within the PTEs */
H. Peter Anvinfe770bf02008-04-17 17:40:45 +020098#define PTE_LEVEL_MULT (PAGE_SIZE)
99#define PMD_LEVEL_MULT (PTRS_PER_PTE * PTE_LEVEL_MULT)
100#define PUD_LEVEL_MULT (PTRS_PER_PMD * PMD_LEVEL_MULT)
101#define PGD_LEVEL_MULT (PTRS_PER_PUD * PUD_LEVEL_MULT)
Arjan van de Ven926e5392008-04-17 17:40:45 +0200102
Borislav Petkovef6bea62014-01-18 12:48:14 +0100103#define pt_dump_seq_printf(m, to_dmesg, fmt, args...) \
104({ \
105 if (to_dmesg) \
106 printk(KERN_INFO fmt, ##args); \
107 else \
108 if (m) \
109 seq_printf(m, fmt, ##args); \
110})
111
112#define pt_dump_cont_printf(m, to_dmesg, fmt, args...) \
113({ \
114 if (to_dmesg) \
115 printk(KERN_CONT fmt, ##args); \
116 else \
117 if (m) \
118 seq_printf(m, fmt, ##args); \
119})
120
Arjan van de Ven926e5392008-04-17 17:40:45 +0200121/*
122 * Print a readable form of a pgprot_t to the seq_file
123 */
Borislav Petkovef6bea62014-01-18 12:48:14 +0100124static void printk_prot(struct seq_file *m, pgprot_t prot, int level, bool dmsg)
Arjan van de Ven926e5392008-04-17 17:40:45 +0200125{
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200126 pgprotval_t pr = pgprot_val(prot);
127 static const char * const level_name[] =
128 { "cr3", "pgd", "pud", "pmd", "pte" };
Arjan van de Ven926e5392008-04-17 17:40:45 +0200129
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200130 if (!pgprot_val(prot)) {
131 /* Not present */
Juergen Grossf439c429c32014-11-03 14:02:01 +0100132 pt_dump_cont_printf(m, dmsg, " ");
Arjan van de Ven926e5392008-04-17 17:40:45 +0200133 } else {
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200134 if (pr & _PAGE_USER)
Borislav Petkovef6bea62014-01-18 12:48:14 +0100135 pt_dump_cont_printf(m, dmsg, "USR ");
Arjan van de Ven926e5392008-04-17 17:40:45 +0200136 else
Borislav Petkovef6bea62014-01-18 12:48:14 +0100137 pt_dump_cont_printf(m, dmsg, " ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200138 if (pr & _PAGE_RW)
Borislav Petkovef6bea62014-01-18 12:48:14 +0100139 pt_dump_cont_printf(m, dmsg, "RW ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200140 else
Borislav Petkovef6bea62014-01-18 12:48:14 +0100141 pt_dump_cont_printf(m, dmsg, "ro ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200142 if (pr & _PAGE_PWT)
Borislav Petkovef6bea62014-01-18 12:48:14 +0100143 pt_dump_cont_printf(m, dmsg, "PWT ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200144 else
Borislav Petkovef6bea62014-01-18 12:48:14 +0100145 pt_dump_cont_printf(m, dmsg, " ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200146 if (pr & _PAGE_PCD)
Borislav Petkovef6bea62014-01-18 12:48:14 +0100147 pt_dump_cont_printf(m, dmsg, "PCD ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200148 else
Borislav Petkovef6bea62014-01-18 12:48:14 +0100149 pt_dump_cont_printf(m, dmsg, " ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200150
Juergen Grossf439c429c32014-11-03 14:02:01 +0100151 /* Bit 7 has a different meaning on level 3 vs 4 */
152 if (level <= 3 && pr & _PAGE_PSE)
153 pt_dump_cont_printf(m, dmsg, "PSE ");
154 else
155 pt_dump_cont_printf(m, dmsg, " ");
156 if ((level == 4 && pr & _PAGE_PAT) ||
157 ((level == 3 || level == 2) && pr & _PAGE_PAT_LARGE))
158 pt_dump_cont_printf(m, dmsg, "pat ");
159 else
160 pt_dump_cont_printf(m, dmsg, " ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200161 if (pr & _PAGE_GLOBAL)
Borislav Petkovef6bea62014-01-18 12:48:14 +0100162 pt_dump_cont_printf(m, dmsg, "GLB ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200163 else
Borislav Petkovef6bea62014-01-18 12:48:14 +0100164 pt_dump_cont_printf(m, dmsg, " ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200165 if (pr & _PAGE_NX)
Borislav Petkovef6bea62014-01-18 12:48:14 +0100166 pt_dump_cont_printf(m, dmsg, "NX ");
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200167 else
Borislav Petkovef6bea62014-01-18 12:48:14 +0100168 pt_dump_cont_printf(m, dmsg, "x ");
Arjan van de Ven926e5392008-04-17 17:40:45 +0200169 }
Borislav Petkovef6bea62014-01-18 12:48:14 +0100170 pt_dump_cont_printf(m, dmsg, "%s\n", level_name[level]);
Arjan van de Ven926e5392008-04-17 17:40:45 +0200171}
172
173/*
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200174 * On 64 bits, sign-extend the 48 bit address to 64 bit
Arjan van de Ven926e5392008-04-17 17:40:45 +0200175 */
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200176static unsigned long normalize_addr(unsigned long u)
Arjan van de Ven926e5392008-04-17 17:40:45 +0200177{
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200178#ifdef CONFIG_X86_64
179 return (signed long)(u << 16) >> 16;
180#else
Arjan van de Ven926e5392008-04-17 17:40:45 +0200181 return u;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200182#endif
Arjan van de Ven926e5392008-04-17 17:40:45 +0200183}
184
185/*
186 * This function gets called on a break in a continuous series
187 * of PTE entries; the next one is different so we need to
188 * print what we collected so far.
189 */
190static void note_page(struct seq_file *m, struct pg_state *st,
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200191 pgprot_t new_prot, int level)
Arjan van de Ven926e5392008-04-17 17:40:45 +0200192{
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200193 pgprotval_t prot, cur;
H. Peter Anvin3891a042014-04-29 16:46:09 -0700194 static const char units[] = "BKMGTPE";
Arjan van de Ven926e5392008-04-17 17:40:45 +0200195
196 /*
197 * If we have a "break" in the series, we need to flush the state that
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200198 * we have now. "break" is either changing perms, levels or
199 * address space marker.
Arjan van de Ven926e5392008-04-17 17:40:45 +0200200 */
Jeremy Fitzhardinge27990ea2008-08-19 13:10:07 -0700201 prot = pgprot_val(new_prot) & PTE_FLAGS_MASK;
202 cur = pgprot_val(st->current_prot) & PTE_FLAGS_MASK;
Arjan van de Ven926e5392008-04-17 17:40:45 +0200203
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200204 if (!st->level) {
205 /* First entry */
206 st->current_prot = new_prot;
207 st->level = level;
208 st->marker = address_markers;
H. Peter Anvin3891a042014-04-29 16:46:09 -0700209 st->lines = 0;
Borislav Petkovef6bea62014-01-18 12:48:14 +0100210 pt_dump_seq_printf(m, st->to_dmesg, "---[ %s ]---\n",
211 st->marker->name);
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200212 } else if (prot != cur || level != st->level ||
213 st->current_address >= st->marker[1].start_address) {
214 const char *unit = units;
Arjan van de Ven926e5392008-04-17 17:40:45 +0200215 unsigned long delta;
Yinghai Lu6424fb32009-04-13 23:51:46 -0700216 int width = sizeof(unsigned long) * 2;
Arjan van de Ven926e5392008-04-17 17:40:45 +0200217
218 /*
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200219 * Now print the actual finished series
220 */
H. Peter Anvin3891a042014-04-29 16:46:09 -0700221 if (!st->marker->max_lines ||
222 st->lines < st->marker->max_lines) {
223 pt_dump_seq_printf(m, st->to_dmesg,
224 "0x%0*lx-0x%0*lx ",
225 width, st->start_address,
226 width, st->current_address);
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200227
H. Peter Anvin3891a042014-04-29 16:46:09 -0700228 delta = st->current_address - st->start_address;
229 while (!(delta & 1023) && unit[1]) {
230 delta >>= 10;
231 unit++;
232 }
233 pt_dump_cont_printf(m, st->to_dmesg, "%9lu%c ",
234 delta, *unit);
235 printk_prot(m, st->current_prot, st->level,
236 st->to_dmesg);
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200237 }
H. Peter Anvin3891a042014-04-29 16:46:09 -0700238 st->lines++;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200239
240 /*
Arjan van de Ven926e5392008-04-17 17:40:45 +0200241 * We print markers for special areas of address space,
242 * such as the start of vmalloc space etc.
243 * This helps in the interpretation.
244 */
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200245 if (st->current_address >= st->marker[1].start_address) {
H. Peter Anvin3891a042014-04-29 16:46:09 -0700246 if (st->marker->max_lines &&
247 st->lines > st->marker->max_lines) {
248 unsigned long nskip =
249 st->lines - st->marker->max_lines;
250 pt_dump_seq_printf(m, st->to_dmesg,
251 "... %lu entr%s skipped ... \n",
252 nskip,
253 nskip == 1 ? "y" : "ies");
254 }
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200255 st->marker++;
H. Peter Anvin3891a042014-04-29 16:46:09 -0700256 st->lines = 0;
Borislav Petkovef6bea62014-01-18 12:48:14 +0100257 pt_dump_seq_printf(m, st->to_dmesg, "---[ %s ]---\n",
258 st->marker->name);
Arjan van de Ven926e5392008-04-17 17:40:45 +0200259 }
260
Arjan van de Ven926e5392008-04-17 17:40:45 +0200261 st->start_address = st->current_address;
262 st->current_prot = new_prot;
263 st->level = level;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200264 }
Arjan van de Ven926e5392008-04-17 17:40:45 +0200265}
266
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200267static void walk_pte_level(struct seq_file *m, struct pg_state *st, pmd_t addr,
Arjan van de Ven926e5392008-04-17 17:40:45 +0200268 unsigned long P)
269{
270 int i;
271 pte_t *start;
272
273 start = (pte_t *) pmd_page_vaddr(addr);
274 for (i = 0; i < PTRS_PER_PTE; i++) {
275 pgprot_t prot = pte_pgprot(*start);
276
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200277 st->current_address = normalize_addr(P + i * PTE_LEVEL_MULT);
Arjan van de Ven926e5392008-04-17 17:40:45 +0200278 note_page(m, st, prot, 4);
279 start++;
280 }
281}
282
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200283#if PTRS_PER_PMD > 1
Arjan van de Ven926e5392008-04-17 17:40:45 +0200284
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200285static void walk_pmd_level(struct seq_file *m, struct pg_state *st, pud_t addr,
Arjan van de Ven926e5392008-04-17 17:40:45 +0200286 unsigned long P)
287{
288 int i;
289 pmd_t *start;
290
291 start = (pmd_t *) pud_page_vaddr(addr);
292 for (i = 0; i < PTRS_PER_PMD; i++) {
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200293 st->current_address = normalize_addr(P + i * PMD_LEVEL_MULT);
Arjan van de Ven926e5392008-04-17 17:40:45 +0200294 if (!pmd_none(*start)) {
Jeremy Fitzhardinge77be1fa2008-07-21 22:59:56 -0700295 pgprotval_t prot = pmd_val(*start) & PTE_FLAGS_MASK;
Arjan van de Ven926e5392008-04-17 17:40:45 +0200296
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200297 if (pmd_large(*start) || !pmd_present(*start))
Arjan van de Ven926e5392008-04-17 17:40:45 +0200298 note_page(m, st, __pgprot(prot), 3);
299 else
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200300 walk_pte_level(m, st, *start,
301 P + i * PMD_LEVEL_MULT);
Arjan van de Ven926e5392008-04-17 17:40:45 +0200302 } else
303 note_page(m, st, __pgprot(0), 3);
304 start++;
305 }
306}
307
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200308#else
309#define walk_pmd_level(m,s,a,p) walk_pte_level(m,s,__pmd(pud_val(a)),p)
310#define pud_large(a) pmd_large(__pmd(pud_val(a)))
311#define pud_none(a) pmd_none(__pmd(pud_val(a)))
312#endif
Arjan van de Ven926e5392008-04-17 17:40:45 +0200313
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200314#if PTRS_PER_PUD > 1
315
316static void walk_pud_level(struct seq_file *m, struct pg_state *st, pgd_t addr,
Arjan van de Ven926e5392008-04-17 17:40:45 +0200317 unsigned long P)
318{
319 int i;
320 pud_t *start;
321
322 start = (pud_t *) pgd_page_vaddr(addr);
323
324 for (i = 0; i < PTRS_PER_PUD; i++) {
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200325 st->current_address = normalize_addr(P + i * PUD_LEVEL_MULT);
Arjan van de Ven926e5392008-04-17 17:40:45 +0200326 if (!pud_none(*start)) {
Jeremy Fitzhardinge77be1fa2008-07-21 22:59:56 -0700327 pgprotval_t prot = pud_val(*start) & PTE_FLAGS_MASK;
Arjan van de Ven926e5392008-04-17 17:40:45 +0200328
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200329 if (pud_large(*start) || !pud_present(*start))
Arjan van de Ven926e5392008-04-17 17:40:45 +0200330 note_page(m, st, __pgprot(prot), 2);
331 else
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200332 walk_pmd_level(m, st, *start,
333 P + i * PUD_LEVEL_MULT);
Arjan van de Ven926e5392008-04-17 17:40:45 +0200334 } else
335 note_page(m, st, __pgprot(0), 2);
336
337 start++;
338 }
339}
340
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200341#else
342#define walk_pud_level(m,s,a,p) walk_pmd_level(m,s,__pud(pgd_val(a)),p)
343#define pgd_large(a) pud_large(__pud(pgd_val(a)))
344#define pgd_none(a) pud_none(__pud(pgd_val(a)))
345#endif
346
Borislav Petkovef6bea62014-01-18 12:48:14 +0100347void ptdump_walk_pgd_level(struct seq_file *m, pgd_t *pgd)
Arjan van de Ven926e5392008-04-17 17:40:45 +0200348{
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200349#ifdef CONFIG_X86_64
Arjan van de Ven926e5392008-04-17 17:40:45 +0200350 pgd_t *start = (pgd_t *) &init_level4_pgt;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200351#else
352 pgd_t *start = swapper_pg_dir;
353#endif
Arjan van de Ven926e5392008-04-17 17:40:45 +0200354 int i;
Borislav Petkovef6bea62014-01-18 12:48:14 +0100355 struct pg_state st = {};
Arjan van de Ven926e5392008-04-17 17:40:45 +0200356
Borislav Petkovef6bea62014-01-18 12:48:14 +0100357 if (pgd) {
358 start = pgd;
359 st.to_dmesg = true;
360 }
Arjan van de Ven926e5392008-04-17 17:40:45 +0200361
362 for (i = 0; i < PTRS_PER_PGD; i++) {
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200363 st.current_address = normalize_addr(i * PGD_LEVEL_MULT);
364 if (!pgd_none(*start)) {
Jeremy Fitzhardinge77be1fa2008-07-21 22:59:56 -0700365 pgprotval_t prot = pgd_val(*start) & PTE_FLAGS_MASK;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200366
367 if (pgd_large(*start) || !pgd_present(*start))
368 note_page(m, &st, __pgprot(prot), 1);
369 else
370 walk_pud_level(m, &st, *start,
371 i * PGD_LEVEL_MULT);
372 } else
Arjan van de Ven926e5392008-04-17 17:40:45 +0200373 note_page(m, &st, __pgprot(0), 1);
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200374
Arjan van de Ven926e5392008-04-17 17:40:45 +0200375 start++;
376 }
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200377
378 /* Flush out the last page */
379 st.current_address = normalize_addr(PTRS_PER_PGD*PGD_LEVEL_MULT);
380 note_page(m, &st, __pgprot(0), 0);
Arjan van de Ven926e5392008-04-17 17:40:45 +0200381}
382
383static int ptdump_show(struct seq_file *m, void *v)
384{
Borislav Petkovef6bea62014-01-18 12:48:14 +0100385 ptdump_walk_pgd_level(m, NULL);
Arjan van de Ven926e5392008-04-17 17:40:45 +0200386 return 0;
387}
388
389static int ptdump_open(struct inode *inode, struct file *filp)
390{
391 return single_open(filp, ptdump_show, NULL);
392}
393
394static const struct file_operations ptdump_fops = {
395 .open = ptdump_open,
396 .read = seq_read,
397 .llseek = seq_lseek,
398 .release = single_release,
399};
400
Ingo Molnara4928cf2008-04-23 13:20:56 +0200401static int pt_dump_init(void)
Arjan van de Ven926e5392008-04-17 17:40:45 +0200402{
403 struct dentry *pe;
404
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200405#ifdef CONFIG_X86_32
406 /* Not a compile-time constant on x86-32 */
Andres Salomon92851e22010-07-20 15:19:46 -0700407 address_markers[VMALLOC_START_NR].start_address = VMALLOC_START;
408 address_markers[VMALLOC_END_NR].start_address = VMALLOC_END;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200409# ifdef CONFIG_HIGHMEM
Andres Salomon92851e22010-07-20 15:19:46 -0700410 address_markers[PKMAP_BASE_NR].start_address = PKMAP_BASE;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200411# endif
Andres Salomon92851e22010-07-20 15:19:46 -0700412 address_markers[FIXADDR_START_NR].start_address = FIXADDR_START;
H. Peter Anvinfe770bf02008-04-17 17:40:45 +0200413#endif
414
Arjan van de Ven926e5392008-04-17 17:40:45 +0200415 pe = debugfs_create_file("kernel_page_tables", 0600, NULL, NULL,
416 &ptdump_fops);
417 if (!pe)
418 return -ENOMEM;
419
420 return 0;
421}
422
423__initcall(pt_dump_init);
424MODULE_LICENSE("GPL");
425MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>");
426MODULE_DESCRIPTION("Kernel debugging helper that dumps pagetables");