[linux-2.6-block.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/errno.h>
#include <linux/fs.h>
#include <linux/io.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/seq_file.h>

#include <asm/fixmap.h>
#include <asm/memory.h>
#include <asm/pgtable.h>
#include <asm/pgtable-hwdef.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
	FIXADDR_START_NR,
	FIXADDR_END_NR,
	PCI_START_NR,
	PCI_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
	{ FIXADDR_START,	"Fixmap start" },
	{ FIXADDR_TOP,		"Fixmap end" },
	{ PCI_IO_START,		"PCI I/O start" },
	{ PCI_IO_END,		"PCI I/O 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)) {
			note_page(st, addr, 3, pmd_val(*pmd));
		} else {
			BUG_ON(pmd_bad(*pmd));
			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)) {
			note_page(st, addr, 2, pud_val(*pud));
		} else {
			BUG_ON(pud_bad(*pud));
			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)) {
			note_page(st, addr, 1, pgd_val(*pgd));
		} else {
			BUG_ON(pgd_bad(*pgd));
			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;

#ifdef CONFIG_SPARSEMEM_VMEMMAP
	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);
#endif

	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>
764011ca	17	#include <linux/errno.h>
c9465b4e	18	#include <linux/fs.h>
284be285	19	#include <linux/io.h>
764011ca	20	#include <linux/init.h>
c9465b4e LA	21	#include <linux/mm.h>
	22	#include <linux/sched.h>
	23	#include <linux/seq_file.h>
	24
	25	#include <asm/fixmap.h>
764011ca	26	#include <asm/memory.h>
c9465b4e	27	#include <asm/pgtable.h>
764011ca	28	#include <asm/pgtable-hwdef.h>
c9465b4e LA	29
	30	#define LOWEST_ADDR (UL(0xffffffffffffffff) << VA_BITS)
	31
	32	struct addr_marker {
	33	unsigned long start_address;
	34	const char *name;
	35	};
	36
	37	enum address_markers_idx {
	38	VMALLOC_START_NR = 0,
	39	VMALLOC_END_NR,
	40	#ifdef CONFIG_SPARSEMEM_VMEMMAP
	41	VMEMMAP_START_NR,
	42	VMEMMAP_END_NR,
	43	#endif
c9465b4e LA	44	FIXADDR_START_NR,
c9465b4e LA	45	FIXADDR_END_NR,
aa03c428 MR	46	PCI_START_NR,
aa03c428 MR	47	PCI_END_NR,
c9465b4e LA	48	MODULES_START_NR,
	49	MODUELS_END_NR,
	50	KERNEL_SPACE_NR,
	51	};
	52
	53	static struct addr_marker address_markers[] = {
	54	{ VMALLOC_START, "vmalloc() Area" },
	55	{ VMALLOC_END, "vmalloc() End" },
	56	#ifdef CONFIG_SPARSEMEM_VMEMMAP
	57	{ 0, "vmemmap start" },
	58	{ 0, "vmemmap end" },
	59	#endif
c9465b4e LA	60	{ FIXADDR_START, "Fixmap start" },
c9465b4e LA	61	{ FIXADDR_TOP, "Fixmap end" },
aa03c428 MR	62	{ PCI_IO_START, "PCI I/O start" },
aa03c428 MR	63	{ PCI_IO_END, "PCI I/O end" },
c9465b4e LA	64	{ MODULES_VADDR, "Modules start" },
	65	{ MODULES_END, "Modules end" },
	66	{ PAGE_OFFSET, "Kernel Mapping" },
	67	{ -1, NULL },
	68	};
	69
	70	struct pg_state {
	71	struct seq_file *seq;
	72	const struct addr_marker *marker;
	73	unsigned long start_address;
	74	unsigned level;
	75	u64 current_prot;
	76	};
	77
	78	struct prot_bits {
	79	u64 mask;
	80	u64 val;
	81	const char *set;
	82	const char *clear;
	83	};
	84
	85	static const struct prot_bits pte_bits[] = {
	86	{
	87	.mask = PTE_USER,
	88	.val = PTE_USER,
	89	.set = "USR",
	90	.clear = " ",
	91	}, {
	92	.mask = PTE_RDONLY,
	93	.val = PTE_RDONLY,
	94	.set = "ro",
	95	.clear = "RW",
	96	}, {
	97	.mask = PTE_PXN,
	98	.val = PTE_PXN,
	99	.set = "NX",
	100	.clear = "x ",
	101	}, {
	102	.mask = PTE_SHARED,
	103	.val = PTE_SHARED,
	104	.set = "SHD",
	105	.clear = " ",
	106	}, {
	107	.mask = PTE_AF,
	108	.val = PTE_AF,
	109	.set = "AF",
	110	.clear = " ",
	111	}, {
	112	.mask = PTE_NG,
	113	.val = PTE_NG,
	114	.set = "NG",
	115	.clear = " ",
	116	}, {
	117	.mask = PTE_UXN,
	118	.val = PTE_UXN,
	119	.set = "UXN",
	120	}, {
	121	.mask = PTE_ATTRINDX_MASK,
	122	.val = PTE_ATTRINDX(MT_DEVICE_nGnRnE),
	123	.set = "DEVICE/nGnRnE",
	124	}, {
	125	.mask = PTE_ATTRINDX_MASK,
	126	.val = PTE_ATTRINDX(MT_DEVICE_nGnRE),
	127	.set = "DEVICE/nGnRE",
128	}, {
129	.mask = PTE_ATTRINDX_MASK,
130	.val = PTE_ATTRINDX(MT_DEVICE_GRE),
131	.set = "DEVICE/GRE",
132	}, {
133	.mask = PTE_ATTRINDX_MASK,
134	.val = PTE_ATTRINDX(MT_NORMAL_NC),
135	.set = "MEM/NORMAL-NC",
136	}, {
137	.mask = PTE_ATTRINDX_MASK,
138	.val = PTE_ATTRINDX(MT_NORMAL),
139	.set = "MEM/NORMAL",
140	}
141	};
142
143	struct pg_level {
144	const struct prot_bits *bits;
145	size_t num;
146	u64 mask;
147	};
148
149	static struct pg_level pg_level[] = {
150	{
151	}, { /* pgd */
152	.bits = pte_bits,
153	.num = ARRAY_SIZE(pte_bits),
154	}, { /* pud */
155	.bits = pte_bits,
156	.num = ARRAY_SIZE(pte_bits),
157	}, { /* pmd */
158	.bits = pte_bits,
159	.num = ARRAY_SIZE(pte_bits),
160	}, { /* pte */
161	.bits = pte_bits,
162	.num = ARRAY_SIZE(pte_bits),
163	},
164	};
165
166	static void dump_prot(struct pg_state st, const struct prot_bits bits,
167	size_t num)
168	{
169	unsigned i;
170
171	for (i = 0; i < num; i++, bits++) {
172	const char *s;
173
174	if ((st->current_prot & bits->mask) == bits->val)
175	s = bits->set;
176	else
177	s = bits->clear;
178
179	if (s)
180	seq_printf(st->seq, " %s", s);
181	}
182	}
183
184	static void note_page(struct pg_state *st, unsigned long addr, unsigned level,
185	u64 val)
186	{
187	static const char units[] = "KMGTPE";
188	u64 prot = val & pg_level[level].mask;
189
c9465b4e LA	190	if (!st->level) {
	191	st->level = level;
	192	st->current_prot = prot;
	193	st->start_address = addr;
	194	seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	195	} else if (prot != st->current_prot \|\| level != st->level \|\|
	196	addr >= st->marker[1].start_address) {
	197	const char *unit = units;
	198	unsigned long delta;
	199
	200	if (st->current_prot) {
	201	seq_printf(st->seq, "0x%16lx-0x%16lx ",
	202	st->start_address, addr);
	203
	204	delta = (addr - st->start_address) >> 10;
	205	while (!(delta & 1023) && unit[1]) {
	206	delta >>= 10;
	207	unit++;
	208	}
	209	seq_printf(st->seq, "%9lu%c", delta, *unit);
	210	if (pg_level[st->level].bits)
	211	dump_prot(st, pg_level[st->level].bits,
	212	pg_level[st->level].num);
	213	seq_puts(st->seq, "\n");
	214	}
	215
	216	if (addr >= st->marker[1].start_address) {
	217	st->marker++;
	218	seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	219	}
	220
	221	st->start_address = addr;
	222	st->current_prot = prot;
	223	st->level = level;
	224	}
	225
	226	if (addr >= st->marker[1].start_address) {
	227	st->marker++;
	228	seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
	229	}
	230
	231	}
	232
	233	static void walk_pte(struct pg_state st, pmd_t pmd, unsigned long start)
	234	{
	235	pte_t *pte = pte_offset_kernel(pmd, 0);
	236	unsigned long addr;
	237	unsigned i;
	238
	239	for (i = 0; i < PTRS_PER_PTE; i++, pte++) {
	240	addr = start + i * PAGE_SIZE;
	241	note_page(st, addr, 4, pte_val(*pte));
	242	}
	243	}
	244
	245	static void walk_pmd(struct pg_state st, pud_t pud, unsigned long start)
	246	{
	247	pmd_t *pmd = pmd_offset(pud, 0);
	248	unsigned long addr;
	249	unsigned i;
	250
	251	for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
	252	addr = start + i * PMD_SIZE;
a1c76574	253	if (pmd_none(pmd) \|\| pmd_sect(pmd)) {
c9465b4e	254	note_page(st, addr, 3, pmd_val(*pmd));
a1c76574 MR	255	} else {
a1c76574 MR	256	BUG_ON(pmd_bad(*pmd));
c9465b4e	257	walk_pte(st, pmd, addr);
a1c76574	258	}
c9465b4e LA	259	}
	260	}
	261
	262	static void walk_pud(struct pg_state st, pgd_t pgd, unsigned long start)
	263	{
	264	pud_t *pud = pud_offset(pgd, 0);
	265	unsigned long addr;
	266	unsigned i;
	267
	268	for (i = 0; i < PTRS_PER_PUD; i++, pud++) {
	269	addr = start + i * PUD_SIZE;
a1c76574	270	if (pud_none(pud) \|\| pud_sect(pud)) {
c9465b4e	271	note_page(st, addr, 2, pud_val(*pud));
a1c76574 MR	272	} else {
a1c76574 MR	273	BUG_ON(pud_bad(*pud));
c9465b4e	274	walk_pmd(st, pud, addr);
a1c76574	275	}
c9465b4e LA	276	}
	277	}
	278
	279	static void walk_pgd(struct pg_state st, struct mm_struct mm, unsigned long start)
	280	{
35545f0c	281	pgd_t *pgd = pgd_offset(mm, 0UL);
c9465b4e LA	282	unsigned i;
	283	unsigned long addr;
	284
	285	for (i = 0; i < PTRS_PER_PGD; i++, pgd++) {
	286	addr = start + i * PGDIR_SIZE;
a1c76574	287	if (pgd_none(*pgd)) {
c9465b4e	288	note_page(st, addr, 1, pgd_val(*pgd));
a1c76574 MR	289	} else {
a1c76574 MR	290	BUG_ON(pgd_bad(*pgd));
c9465b4e	291	walk_pud(st, pgd, addr);
a1c76574	292	}
c9465b4e LA	293	}
	294	}
	295
	296	static int ptdump_show(struct seq_file m, void v)
	297	{
	298	struct pg_state st = {
	299	.seq = m,
	300	.marker = address_markers,
	301	};
	302
	303	walk_pgd(&st, &init_mm, LOWEST_ADDR);
	304
	305	note_page(&st, 0, 0, 0);
	306	return 0;
	307	}
	308
	309	static int ptdump_open(struct inode inode, struct file file)
	310	{
	311	return single_open(file, ptdump_show, NULL);
	312	}
	313
	314	static const struct file_operations ptdump_fops = {
	315	.open = ptdump_open,
	316	.read = seq_read,
	317	.llseek = seq_lseek,
	318	.release = single_release,
	319	};
	320
	321	static int ptdump_init(void)
	322	{
	323	struct dentry *pe;
	324	unsigned i, j;
	325
	326	for (i = 0; i < ARRAY_SIZE(pg_level); i++)
	327	if (pg_level[i].bits)
	328	for (j = 0; j < pg_level[i].num; j++)
	329	pg_level[i].mask \|= pg_level[i].bits[j].mask;
	330
326a7803	331	#ifdef CONFIG_SPARSEMEM_VMEMMAP
c9465b4e LA	332	address_markers[VMEMMAP_START_NR].start_address =
	333	(unsigned long)virt_to_page(PAGE_OFFSET);
	334	address_markers[VMEMMAP_END_NR].start_address =
	335	(unsigned long)virt_to_page(high_memory);
326a7803	336	#endif
c9465b4e LA	337
	338	pe = debugfs_create_file("kernel_page_tables", 0400, NULL, NULL,
	339	&ptdump_fops);
	340	return pe ? 0 : -ENOMEM;
	341	}
	342	device_initcall(ptdump_init);