diff options
| -rw-r--r-- | arch/arm/Kconfig.debug | 6 | ||||
| -rw-r--r-- | arch/arm/include/asm/ptdump.h | 35 | ||||
| -rw-r--r-- | arch/arm/mm/Makefile | 3 | ||||
| -rw-r--r-- | arch/arm/mm/dump.c | 65 | ||||
| -rw-r--r-- | arch/arm/mm/ptdump_debugfs.c | 34 |
5 files changed, 104 insertions, 39 deletions
diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug index 17685e19aed8..e7b94dbae78e 100644 --- a/arch/arm/Kconfig.debug +++ b/arch/arm/Kconfig.debug @@ -3,10 +3,14 @@ menu "Kernel hacking" source "lib/Kconfig.debug" -config ARM_PTDUMP +config ARM_PTDUMP_CORE + def_bool n + +config ARM_PTDUMP_DEBUGFS bool "Export kernel pagetable layout to userspace via debugfs" depends on DEBUG_KERNEL depends on MMU + select ARM_PTDUMP_CORE select DEBUG_FS ---help--- Say Y here if you want to show the kernel pagetable layout in a diff --git a/arch/arm/include/asm/ptdump.h b/arch/arm/include/asm/ptdump.h new file mode 100644 index 000000000000..45d2de313eda --- /dev/null +++ b/arch/arm/include/asm/ptdump.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (C) 2014 ARM Ltd. */ +#ifndef __ASM_PTDUMP_H +#define __ASM_PTDUMP_H + +#ifdef CONFIG_ARM_PTDUMP_CORE + +#include <linux/mm_types.h> +#include <linux/seq_file.h> + +struct addr_marker { + unsigned long start_address; + char *name; +}; + +struct ptdump_info { + struct mm_struct *mm; + const struct addr_marker *markers; + unsigned long base_addr; +}; + +void ptdump_walk_pgd(struct seq_file *s, struct ptdump_info *info); +#ifdef CONFIG_ARM_PTDUMP_DEBUGFS +int ptdump_debugfs_register(struct ptdump_info *info, const char *name); +#else +static inline int ptdump_debugfs_register(struct ptdump_info *info, + const char *name) +{ + return 0; +} +#endif /* CONFIG_ARM_PTDUMP_DEBUGFS */ + +#endif /* CONFIG_ARM_PTDUMP_CORE */ + +#endif /* __ASM_PTDUMP_H */ diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile index 465bcf757b9e..9dbb84923e12 100644 --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -13,7 +13,8 @@ obj-y += nommu.o obj-$(CONFIG_ARM_MPU) += pmsa-v7.o endif -obj-$(CONFIG_ARM_PTDUMP) += dump.o +obj-$(CONFIG_ARM_PTDUMP_CORE) += dump.o +obj-$(CONFIG_ARM_PTDUMP_DEBUGFS) += ptdump_debugfs.o obj-$(CONFIG_MODULES) += proc-syms.o obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c index fc3b44028cfb..8dfe7c36269d 100644 --- a/arch/arm/mm/dump.c +++ b/arch/arm/mm/dump.c @@ -21,11 +21,7 @@ #include <asm/fixmap.h> #include <asm/memory.h> #include <asm/pgtable.h> - -struct addr_marker { - unsigned long start_address; - const char *name; -}; +#include <asm/ptdump.h> static struct addr_marker address_markers[] = { { MODULES_VADDR, "Modules" }, @@ -335,50 +331,36 @@ static void walk_pud(struct pg_state *st, pgd_t *pgd, unsigned long start) } } -static void walk_pgd(struct seq_file *m) +static void walk_pgd(struct pg_state *st, struct mm_struct *mm, + unsigned long start) { - pgd_t *pgd = swapper_pg_dir; - struct pg_state st; - unsigned long addr; + pgd_t *pgd = pgd_offset(mm, 0UL); unsigned i; - - memset(&st, 0, sizeof(st)); - st.seq = m; - st.marker = address_markers; + unsigned long addr; for (i = 0; i < PTRS_PER_PGD; i++, pgd++) { - addr = i * PGDIR_SIZE; + addr = start + i * PGDIR_SIZE; if (!pgd_none(*pgd)) { - walk_pud(&st, pgd, addr); + walk_pud(st, pgd, addr); } else { - note_page(&st, addr, 1, pgd_val(*pgd), NULL); + note_page(st, addr, 1, pgd_val(*pgd), NULL); } } - - note_page(&st, 0, 0, 0, NULL); } -static int ptdump_show(struct seq_file *m, void *v) +void ptdump_walk_pgd(struct seq_file *m, struct ptdump_info *info) { - walk_pgd(m); - return 0; -} + struct pg_state st = { + .seq = m, + .marker = info->markers, + }; -static int ptdump_open(struct inode *inode, struct file *file) -{ - return single_open(file, ptdump_show, NULL); + walk_pgd(&st, info->mm, info->base_addr); + note_page(&st, 0, 0, 0, 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) +static void ptdump_initialize(void) { - struct dentry *pe; unsigned i, j; for (i = 0; i < ARRAY_SIZE(pg_level); i++) @@ -387,9 +369,18 @@ static int ptdump_init(void) pg_level[i].mask |= pg_level[i].bits[j].mask; address_markers[2].start_address = VMALLOC_START; +} - pe = debugfs_create_file("kernel_page_tables", 0400, NULL, NULL, - &ptdump_fops); - return pe ? 0 : -ENOMEM; +static struct ptdump_info kernel_ptdump_info = { + .mm = &init_mm, + .markers = address_markers, + .base_addr = 0, +}; + +static int ptdump_init(void) +{ + ptdump_initialize(); + return ptdump_debugfs_register(&kernel_ptdump_info, + "kernel_page_tables"); } __initcall(ptdump_init); diff --git a/arch/arm/mm/ptdump_debugfs.c b/arch/arm/mm/ptdump_debugfs.c new file mode 100644 index 000000000000..be8d87be4b93 --- /dev/null +++ b/arch/arm/mm/ptdump_debugfs.c @@ -0,0 +1,34 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/debugfs.h> +#include <linux/seq_file.h> + +#include <asm/ptdump.h> + +static int ptdump_show(struct seq_file *m, void *v) +{ + struct ptdump_info *info = m->private; + + ptdump_walk_pgd(m, info); + return 0; +} + +static int ptdump_open(struct inode *inode, struct file *file) +{ + return single_open(file, ptdump_show, inode->i_private); +} + +static const struct file_operations ptdump_fops = { + .open = ptdump_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +int ptdump_debugfs_register(struct ptdump_info *info, const char *name) +{ + struct dentry *pe; + + pe = debugfs_create_file(name, 0400, NULL, info, &ptdump_fops); + return pe ? 0 : -ENOMEM; + +} |