[deliverable/linux.git] / arch / arm64 / mm / dump.c

/*
 * Copyright (c) 2014, The Linux Foundation. All rights reserved.
 * Debug helper to dump the current kernel pagetables of the system
 * so that we can see what the various memory ranges are set to.
 *
 * Derived from x86 and arm implementation:
 * (C) Copyright 2008 Intel Corporation
 *
 * Author: Arjan van de Ven <arjan@linux.intel.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; version 2
 * of the License.
 */
#include <linux/debugfs.h>
#include <linux/fs.h>
#include <linux/io.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/seq_file.h>

#include <asm/fixmap.h>
#include <asm/pgtable.h>

#define LOWEST_ADDR	(UL(0xffffffffffffffff) << VA_BITS)

struct addr_marker {
	unsigned long start_address;
	const char *name;
};

enum address_markers_idx {
	VMALLOC_START_NR = 0,
	VMALLOC_END_NR,
#ifdef CONFIG_SPARSEMEM_VMEMMAP
	VMEMMAP_START_NR,
	VMEMMAP_END_NR,
#endif
	PCI_START_NR,
	PCI_END_NR,
	FIXADDR_START_NR,
	FIXADDR_END_NR,
	MODULES_START_NR,
	MODUELS_END_NR,
	KERNEL_SPACE_NR,
};

static struct addr_marker address_markers[] = {
	{ VMALLOC_START,	"vmalloc() Area" },
	{ VMALLOC_END,		"vmalloc() End" },
#ifdef CONFIG_SPARSEMEM_VMEMMAP
	{ 0,			"vmemmap start" },
	{ 0,			"vmemmap end" },
#endif
	{ (unsigned long) PCI_IOBASE,		"PCI I/O start" },
	{ (unsigned long) PCI_IOBASE + SZ_16M,	"PCI I/O end" },
	{ FIXADDR_START,	"Fixmap start" },
	{ FIXADDR_TOP,		"Fixmap end" },
	{ MODULES_VADDR,	"Modules start" },
	{ MODULES_END,		"Modules end" },
	{ PAGE_OFFSET,		"Kernel Mapping" },
	{ -1,			NULL },
};

struct pg_state {
	struct seq_file *seq;
	const struct addr_marker *marker;
	unsigned long start_address;
	unsigned level;
	u64 current_prot;
};

struct prot_bits {
	u64		mask;
	u64		val;
	const char	*set;
	const char	*clear;
};

static const struct prot_bits pte_bits[] = {
	{
		.mask	= PTE_USER,
		.val	= PTE_USER,
		.set	= "USR",
		.clear	= "   ",
	}, {
		.mask	= PTE_RDONLY,
		.val	= PTE_RDONLY,
		.set	= "ro",
		.clear	= "RW",
	}, {
		.mask	= PTE_PXN,
		.val	= PTE_PXN,
		.set	= "NX",
		.clear	= "x ",
	}, {
		.mask	= PTE_SHARED,
		.val	= PTE_SHARED,
		.set	= "SHD",
		.clear	= "   ",
	}, {
		.mask	= PTE_AF,
		.val	= PTE_AF,
		.set	= "AF",
		.clear	= "  ",
	}, {
		.mask	= PTE_NG,
		.val	= PTE_NG,
		.set	= "NG",
		.clear	= "  ",
	}, {
		.mask	= PTE_UXN,
		.val	= PTE_UXN,
		.set	= "UXN",
	}, {
		.mask	= PTE_ATTRINDX_MASK,
		.val	= PTE_ATTRINDX(MT_DEVICE_nGnRnE),
		.set	= "DEVICE/nGnRnE",
	}, {
		.mask	= PTE_ATTRINDX_MASK,
		.val	= PTE_ATTRINDX(MT_DEVICE_nGnRE),
		.set	= "DEVICE/nGnRE",
	}, {
		.mask	= PTE_ATTRINDX_MASK,
		.val	= PTE_ATTRINDX(MT_DEVICE_GRE),
		.set	= "DEVICE/GRE",
	}, {
		.mask	= PTE_ATTRINDX_MASK,
		.val	= PTE_ATTRINDX(MT_NORMAL_NC),
		.set	= "MEM/NORMAL-NC",
	}, {
		.mask	= PTE_ATTRINDX_MASK,
		.val	= PTE_ATTRINDX(MT_NORMAL),
		.set	= "MEM/NORMAL",
	}
};

struct pg_level {
	const struct prot_bits *bits;
	size_t num;
	u64 mask;
};

static struct pg_level pg_level[] = {
	{
	}, { /* pgd */
		.bits	= pte_bits,
		.num	= ARRAY_SIZE(pte_bits),
	}, { /* pud */
		.bits	= pte_bits,
		.num	= ARRAY_SIZE(pte_bits),
	}, { /* pmd */
		.bits	= pte_bits,
		.num	= ARRAY_SIZE(pte_bits),
	}, { /* pte */
		.bits	= pte_bits,
		.num	= ARRAY_SIZE(pte_bits),
	},
};

static void dump_prot(struct pg_state *st, const struct prot_bits *bits,
			size_t num)
{
	unsigned i;

	for (i = 0; i < num; i++, bits++) {
		const char *s;

		if ((st->current_prot & bits->mask) == bits->val)
			s = bits->set;
		else
			s = bits->clear;

		if (s)
			seq_printf(st->seq, " %s", s);
	}
}

static void note_page(struct pg_state *st, unsigned long addr, unsigned level,
				u64 val)
{
	static const char units[] = "KMGTPE";
	u64 prot = val & pg_level[level].mask;

	if (!st->level) {
		st->level = level;
		st->current_prot = prot;
		st->start_address = addr;
		seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	} else if (prot != st->current_prot || level != st->level ||
		   addr >= st->marker[1].start_address) {
		const char *unit = units;
		unsigned long delta;

		if (st->current_prot) {
			seq_printf(st->seq, "0x%16lx-0x%16lx   ",
				   st->start_address, addr);

			delta = (addr - st->start_address) >> 10;
			while (!(delta & 1023) && unit[1]) {
				delta >>= 10;
				unit++;
			}
			seq_printf(st->seq, "%9lu%c", delta, *unit);
			if (pg_level[st->level].bits)
				dump_prot(st, pg_level[st->level].bits,
					  pg_level[st->level].num);
			seq_puts(st->seq, "\n");
		}

		if (addr >= st->marker[1].start_address) {
			st->marker++;
			seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
		}

		st->start_address = addr;
		st->current_prot = prot;
		st->level = level;
	}

	if (addr >= st->marker[1].start_address) {
		st->marker++;
		seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	}

}

static void walk_pte(struct pg_state *st, pmd_t *pmd, unsigned long start)
{
	pte_t *pte = pte_offset_kernel(pmd, 0);
	unsigned long addr;
	unsigned i;

	for (i = 0; i < PTRS_PER_PTE; i++, pte++) {
		addr = start + i * PAGE_SIZE;
		note_page(st, addr, 4, pte_val(*pte));
	}
}

static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
{
	pmd_t *pmd = pmd_offset(pud, 0);
	unsigned long addr;
	unsigned i;

	for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
		addr = start + i * PMD_SIZE;
		if (pmd_none(*pmd) || pmd_sect(*pmd) || pmd_bad(*pmd))
			note_page(st, addr, 3, pmd_val(*pmd));
		else
			walk_pte(st, pmd, addr);
	}
}

static void walk_pud(struct pg_state *st, pgd_t *pgd, unsigned long start)
{
	pud_t *pud = pud_offset(pgd, 0);
	unsigned long addr;
	unsigned i;

	for (i = 0; i < PTRS_PER_PUD; i++, pud++) {
		addr = start + i * PUD_SIZE;
		if (pud_none(*pud) || pud_sect(*pud) || pud_bad(*pud))
			note_page(st, addr, 2, pud_val(*pud));
		else
			walk_pmd(st, pud, addr);
	}
}

static void walk_pgd(struct pg_state *st, struct mm_struct *mm, unsigned long start)
{
	pgd_t *pgd = pgd_offset(mm, 0UL);
	unsigned i;
	unsigned long addr;

	for (i = 0; i < PTRS_PER_PGD; i++, pgd++) {
		addr = start + i * PGDIR_SIZE;
		if (pgd_none(*pgd) || pgd_bad(*pgd))
			note_page(st, addr, 1, pgd_val(*pgd));
		else
			walk_pud(st, pgd, addr);
	}
}

static int ptdump_show(struct seq_file *m, void *v)
{
	struct pg_state st = {
		.seq = m,
		.marker = address_markers,
	};

	walk_pgd(&st, &init_mm, LOWEST_ADDR);

	note_page(&st, 0, 0, 0);
	return 0;
}

static int ptdump_open(struct inode *inode, struct file *file)
{
	return single_open(file, ptdump_show, NULL);
}

static const struct file_operations ptdump_fops = {
	.open		= ptdump_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static int ptdump_init(void)
{
	struct dentry *pe;
	unsigned i, j;

	for (i = 0; i < ARRAY_SIZE(pg_level); i++)
		if (pg_level[i].bits)
			for (j = 0; j < pg_level[i].num; j++)
				pg_level[i].mask |= pg_level[i].bits[j].mask;

	address_markers[VMEMMAP_START_NR].start_address =
				(unsigned long)virt_to_page(PAGE_OFFSET);
	address_markers[VMEMMAP_END_NR].start_address =
				(unsigned long)virt_to_page(high_memory);

	pe = debugfs_create_file("kernel_page_tables", 0400, NULL, NULL,
				 &ptdump_fops);
	return pe ? 0 : -ENOMEM;
}
device_initcall(ptdump_init);
Commit	Line	Data
c9465b4e LA	1	/*
	2	* Copyright (c) 2014, The Linux Foundation. All rights reserved.
	3	* Debug helper to dump the current kernel pagetables of the system
	4	* so that we can see what the various memory ranges are set to.
	5	*
	6	* Derived from x86 and arm implementation:
	7	* (C) Copyright 2008 Intel Corporation
	8	*
	9	* Author: Arjan van de Ven <arjan@linux.intel.com>
	10	*
	11	* This program is free software; you can redistribute it and/or
	12	* modify it under the terms of the GNU General Public License
	13	* as published by the Free Software Foundation; version 2
	14	* of the License.
	15	*/
	16	#include <linux/debugfs.h>
	17	#include <linux/fs.h>
284be285	18	#include <linux/io.h>
c9465b4e LA	19	#include <linux/mm.h>
	20	#include <linux/sched.h>
	21	#include <linux/seq_file.h>
	22
	23	#include <asm/fixmap.h>
	24	#include <asm/pgtable.h>
	25
	26	#define LOWEST_ADDR (UL(0xffffffffffffffff) << VA_BITS)
	27
	28	struct addr_marker {
	29	unsigned long start_address;
	30	const char *name;
	31	};
	32
	33	enum address_markers_idx {
	34	VMALLOC_START_NR = 0,
	35	VMALLOC_END_NR,
	36	#ifdef CONFIG_SPARSEMEM_VMEMMAP
	37	VMEMMAP_START_NR,
	38	VMEMMAP_END_NR,
	39	#endif
	40	PCI_START_NR,
	41	PCI_END_NR,
	42	FIXADDR_START_NR,
	43	FIXADDR_END_NR,
	44	MODULES_START_NR,
	45	MODUELS_END_NR,
	46	KERNEL_SPACE_NR,
	47	};
	48
	49	static struct addr_marker address_markers[] = {
	50	{ VMALLOC_START, "vmalloc() Area" },
	51	{ VMALLOC_END, "vmalloc() End" },
	52	#ifdef CONFIG_SPARSEMEM_VMEMMAP
	53	{ 0, "vmemmap start" },
	54	{ 0, "vmemmap end" },
	55	#endif
	56	{ (unsigned long) PCI_IOBASE, "PCI I/O start" },
	57	{ (unsigned long) PCI_IOBASE + SZ_16M, "PCI I/O end" },
	58	{ FIXADDR_START, "Fixmap start" },
	59	{ FIXADDR_TOP, "Fixmap end" },
	60	{ MODULES_VADDR, "Modules start" },
	61	{ MODULES_END, "Modules end" },
	62	{ PAGE_OFFSET, "Kernel Mapping" },
	63	{ -1, NULL },
	64	};
	65
	66	struct pg_state {
	67	struct seq_file *seq;
	68	const struct addr_marker *marker;
	69	unsigned long start_address;
	70	unsigned level;
	71	u64 current_prot;
	72	};
	73
	74	struct prot_bits {
	75	u64 mask;
	76	u64 val;
	77	const char *set;
	78	const char *clear;
	79	};
	80
	81	static const struct prot_bits pte_bits[] = {
	82	{
83	.mask = PTE_USER,
84	.val = PTE_USER,
85	.set = "USR",
86	.clear = " ",
87	}, {
88	.mask = PTE_RDONLY,
89	.val = PTE_RDONLY,
90	.set = "ro",
91	.clear = "RW",
92	}, {
93	.mask = PTE_PXN,
94	.val = PTE_PXN,
95	.set = "NX",
96	.clear = "x ",
97	}, {
98	.mask = PTE_SHARED,
99	.val = PTE_SHARED,
100	.set = "SHD",
101	.clear = " ",
102	}, {
103	.mask = PTE_AF,
104	.val = PTE_AF,
105	.set = "AF",
106	.clear = " ",
107	}, {
108	.mask = PTE_NG,
109	.val = PTE_NG,
110	.set = "NG",
111	.clear = " ",
112	}, {
113	.mask = PTE_UXN,
114	.val = PTE_UXN,
115	.set = "UXN",
116	}, {
117	.mask = PTE_ATTRINDX_MASK,
118	.val = PTE_ATTRINDX(MT_DEVICE_nGnRnE),
119	.set = "DEVICE/nGnRnE",
120	}, {
121	.mask = PTE_ATTRINDX_MASK,
122	.val = PTE_ATTRINDX(MT_DEVICE_nGnRE),
123	.set = "DEVICE/nGnRE",
124	}, {
125	.mask = PTE_ATTRINDX_MASK,
126	.val = PTE_ATTRINDX(MT_DEVICE_GRE),
127	.set = "DEVICE/GRE",
128	}, {
129	.mask = PTE_ATTRINDX_MASK,
130	.val = PTE_ATTRINDX(MT_NORMAL_NC),
131	.set = "MEM/NORMAL-NC",
132	}, {
133	.mask = PTE_ATTRINDX_MASK,
134	.val = PTE_ATTRINDX(MT_NORMAL),
135	.set = "MEM/NORMAL",
136	}
137	};
138
139	struct pg_level {
140	const struct prot_bits *bits;
141	size_t num;
142	u64 mask;
143	};
144
145	static struct pg_level pg_level[] = {
146	{
147	}, { /* pgd */
148	.bits = pte_bits,
149	.num = ARRAY_SIZE(pte_bits),
150	}, { /* pud */
151	.bits = pte_bits,
152	.num = ARRAY_SIZE(pte_bits),
153	}, { /* pmd */
154	.bits = pte_bits,
155	.num = ARRAY_SIZE(pte_bits),
156	}, { /* pte */
157	.bits = pte_bits,
158	.num = ARRAY_SIZE(pte_bits),
159	},
160	};
161
162	static void dump_prot(struct pg_state st, const struct prot_bits bits,
163	size_t num)
164	{
165	unsigned i;
166
167	for (i = 0; i < num; i++, bits++) {
168	const char *s;
169
170	if ((st->current_prot & bits->mask) == bits->val)
171	s = bits->set;
172	else
173	s = bits->clear;
174
175	if (s)
176	seq_printf(st->seq, " %s", s);
177	}
178	}
179
180	static void note_page(struct pg_state *st, unsigned long addr, unsigned level,
181	u64 val)
182	{
183	static const char units[] = "KMGTPE";
184	u64 prot = val & pg_level[level].mask;
185
c9465b4e LA	186	if (!st->level) {
	187	st->level = level;
	188	st->current_prot = prot;
	189	st->start_address = addr;
	190	seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	191	} else if (prot != st->current_prot \|\| level != st->level \|\|
	192	addr >= st->marker[1].start_address) {
	193	const char *unit = units;
	194	unsigned long delta;
	195
	196	if (st->current_prot) {
	197	seq_printf(st->seq, "0x%16lx-0x%16lx ",
	198	st->start_address, addr);
	199
	200	delta = (addr - st->start_address) >> 10;
	201	while (!(delta & 1023) && unit[1]) {
	202	delta >>= 10;
	203	unit++;
	204	}
	205	seq_printf(st->seq, "%9lu%c", delta, *unit);
	206	if (pg_level[st->level].bits)
	207	dump_prot(st, pg_level[st->level].bits,
	208	pg_level[st->level].num);
	209	seq_puts(st->seq, "\n");
	210	}
	211
	212	if (addr >= st->marker[1].start_address) {
	213	st->marker++;
	214	seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	215	}
	216
	217	st->start_address = addr;
	218	st->current_prot = prot;
	219	st->level = level;
	220	}
	221
	222	if (addr >= st->marker[1].start_address) {
	223	st->marker++;
	224	seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	225	}
	226
	227	}
	228
	229	static void walk_pte(struct pg_state st, pmd_t pmd, unsigned long start)
	230	{
	231	pte_t *pte = pte_offset_kernel(pmd, 0);
	232	unsigned long addr;
	233	unsigned i;
	234
	235	for (i = 0; i < PTRS_PER_PTE; i++, pte++) {
	236	addr = start + i * PAGE_SIZE;
	237	note_page(st, addr, 4, pte_val(*pte));
	238	}
	239	}
	240
	241	static void walk_pmd(struct pg_state st, pud_t pud, unsigned long start)
	242	{
	243	pmd_t *pmd = pmd_offset(pud, 0);
	244	unsigned long addr;
	245	unsigned i;
	246
	247	for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
	248	addr = start + i * PMD_SIZE;
	249	if (pmd_none(pmd) \|\| pmd_sect(pmd) \|\| pmd_bad(*pmd))
250	note_page(st, addr, 3, pmd_val(*pmd));
251	else
252	walk_pte(st, pmd, addr);
253	}
254	}
255
256	static void walk_pud(struct pg_state st, pgd_t pgd, unsigned long start)
257	{
258	pud_t *pud = pud_offset(pgd, 0);
259	unsigned long addr;
260	unsigned i;
261
262	for (i = 0; i < PTRS_PER_PUD; i++, pud++) {
263	addr = start + i * PUD_SIZE;
264	if (pud_none(pud) \|\| pud_sect(pud) \|\| pud_bad(*pud))
265	note_page(st, addr, 2, pud_val(*pud));
266	else
267	walk_pmd(st, pud, addr);
268	}
269	}
270
271	static void walk_pgd(struct pg_state st, struct mm_struct mm, unsigned long start)
272	{
35545f0c	273	pgd_t *pgd = pgd_offset(mm, 0UL);
c9465b4e LA	274	unsigned i;
	275	unsigned long addr;
	276
	277	for (i = 0; i < PTRS_PER_PGD; i++, pgd++) {
	278	addr = start + i * PGDIR_SIZE;
	279	if (pgd_none(pgd) \|\| pgd_bad(pgd))
	280	note_page(st, addr, 1, pgd_val(*pgd));
	281	else
	282	walk_pud(st, pgd, addr);
	283	}
	284	}
	285
	286	static int ptdump_show(struct seq_file m, void v)
	287	{
	288	struct pg_state st = {
	289	.seq = m,
	290	.marker = address_markers,
	291	};
	292
	293	walk_pgd(&st, &init_mm, LOWEST_ADDR);
	294
	295	note_page(&st, 0, 0, 0);
	296	return 0;
	297	}
	298
	299	static int ptdump_open(struct inode inode, struct file file)
	300	{
	301	return single_open(file, ptdump_show, NULL);
	302	}
	303
	304	static const struct file_operations ptdump_fops = {
	305	.open = ptdump_open,
	306	.read = seq_read,
	307	.llseek = seq_lseek,
	308	.release = single_release,
	309	};
	310
	311	static int ptdump_init(void)
	312	{
	313	struct dentry *pe;
	314	unsigned i, j;
	315
	316	for (i = 0; i < ARRAY_SIZE(pg_level); i++)
	317	if (pg_level[i].bits)
	318	for (j = 0; j < pg_level[i].num; j++)
	319	pg_level[i].mask \|= pg_level[i].bits[j].mask;
	320
	321	address_markers[VMEMMAP_START_NR].start_address =
	322	(unsigned long)virt_to_page(PAGE_OFFSET);
	323	address_markers[VMEMMAP_END_NR].start_address =
	324	(unsigned long)virt_to_page(high_memory);
	325
	326	pe = debugfs_create_file("kernel_page_tables", 0400, NULL, NULL,
	327	&ptdump_fops);
	328	return pe ? 0 : -ENOMEM;
	329	}
	330	device_initcall(ptdump_init);