[PATCHv3 1/4] arm64: dump: Make ptdump debugfs a separate option
From: Laura Abbott
Date: Tue Oct 18 2016 - 18:02:31 EST
ptdump_register currently initializes a set of page table information and
registers debugfs. There are uses for the ptdump option without wanting the
debugfs options. Split this out to make it a separate option.
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: Mark Rutland <mark.rutland@xxxxxxx>
Tested-by: Mark Rutland <mark.rutland@xxxxxxx>
Signed-off-by: Laura Abbott <labbott@xxxxxxxxxx>
---
v3: Minor header guard fixup.
Mark Rutland pointed out that this needs to be reviewed by the EFI maintainers
so I'm explicitly adding appropriate people/lists.
---
arch/arm64/Kconfig.debug | 6 +++++-
arch/arm64/include/asm/ptdump.h | 15 +++++++++------
arch/arm64/mm/Makefile | 3 ++-
arch/arm64/mm/dump.c | 26 +++++---------------------
arch/arm64/mm/ptdump_debugfs.c | 31 +++++++++++++++++++++++++++++++
drivers/firmware/efi/arm-runtime.c | 4 ++--
6 files changed, 54 insertions(+), 31 deletions(-)
create mode 100644 arch/arm64/mm/ptdump_debugfs.c
diff --git a/arch/arm64/Kconfig.debug b/arch/arm64/Kconfig.debug
index b661fe7..21a5b74 100644
--- a/arch/arm64/Kconfig.debug
+++ b/arch/arm64/Kconfig.debug
@@ -2,9 +2,13 @@ menu "Kernel hacking"
source "lib/Kconfig.debug"
-config ARM64_PTDUMP
+config ARM64_PTDUMP_CORE
+ def_bool n
+
+config ARM64_PTDUMP_DEBUGFS
bool "Export kernel pagetable layout to userspace via debugfs"
depends on DEBUG_KERNEL
+ select ARM64_PTDUMP_CORE
select DEBUG_FS
help
Say Y here if you want to show the kernel pagetable layout in a
diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h
index 07b8ed0..16335da 100644
--- a/arch/arm64/include/asm/ptdump.h
+++ b/arch/arm64/include/asm/ptdump.h
@@ -16,9 +16,10 @@
#ifndef __ASM_PTDUMP_H
#define __ASM_PTDUMP_H
-#ifdef CONFIG_ARM64_PTDUMP
+#ifdef CONFIG_ARM64_PTDUMP_CORE
#include <linux/mm_types.h>
+#include <linux/seq_file.h>
struct addr_marker {
unsigned long start_address;
@@ -32,13 +33,15 @@ struct ptdump_info {
unsigned long max_addr;
};
-int ptdump_register(struct ptdump_info *info, const char *name);
-
+void ptdump_walk_pgd(struct seq_file *s, struct ptdump_info *info);
+#ifdef CONFIG_ARM64_PTDUMP_DEBUGFS
+int ptdump_debugfs_register(struct ptdump_info *info, const char *name);
#else
-static inline int ptdump_register(struct ptdump_info *info, const char *name)
+static inline int ptdump_debugfs_register(struct ptdump_info *info,
+ const char *name)
{
return 0;
}
-#endif /* CONFIG_ARM64_PTDUMP */
-
+#endif
+#endif /* CONFIG_ARM64_PTDUMP_CORE */
#endif /* __ASM_PTDUMP_H */
diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile
index 54bb209..e703fb9 100644
--- a/arch/arm64/mm/Makefile
+++ b/arch/arm64/mm/Makefile
@@ -3,7 +3,8 @@ obj-y := dma-mapping.o extable.o fault.o init.o \
ioremap.o mmap.o pgd.o mmu.o \
context.o proc.o pageattr.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
-obj-$(CONFIG_ARM64_PTDUMP) += dump.o
+obj-$(CONFIG_ARM64_PTDUMP_CORE) += dump.o
+obj-$(CONFIG_ARM64_PTDUMP_DEBUGFS) += ptdump_debugfs.o
obj-$(CONFIG_NUMA) += numa.o
obj-$(CONFIG_KASAN) += kasan_init.o
diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/dump.c
index 9c3e75d..f0f0be7 100644
--- a/arch/arm64/mm/dump.c
+++ b/arch/arm64/mm/dump.c
@@ -304,9 +304,8 @@ static void walk_pgd(struct pg_state *st, struct mm_struct *mm,
}
}
-static int ptdump_show(struct seq_file *m, void *v)
+void ptdump_walk_pgd(struct seq_file *m, struct ptdump_info *info)
{
- struct ptdump_info *info = m->private;
struct pg_state st = {
.seq = m,
.marker = info->markers,
@@ -315,33 +314,16 @@ static int ptdump_show(struct seq_file *m, void *v)
walk_pgd(&st, info->mm, info->base_addr);
note_page(&st, 0, 0, 0);
- return 0;
}
-static int ptdump_open(struct inode *inode, struct file *file)
+static void ptdump_initialize(void)
{
- 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_register(struct ptdump_info *info, const char *name)
-{
- 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;
-
- pe = debugfs_create_file(name, 0400, NULL, info, &ptdump_fops);
- return pe ? 0 : -ENOMEM;
}
static struct ptdump_info kernel_ptdump_info = {
@@ -352,6 +334,8 @@ static struct ptdump_info kernel_ptdump_info = {
static int ptdump_init(void)
{
- return ptdump_register(&kernel_ptdump_info, "kernel_page_tables");
+ ptdump_initialize();
+ return ptdump_debugfs_register(&kernel_ptdump_info,
+ "kernel_page_tables");
}
device_initcall(ptdump_init);
diff --git a/arch/arm64/mm/ptdump_debugfs.c b/arch/arm64/mm/ptdump_debugfs.c
new file mode 100644
index 0000000..eee4d86
--- /dev/null
+++ b/arch/arm64/mm/ptdump_debugfs.c
@@ -0,0 +1,31 @@
+#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;
+
+}
diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
index 7c75a8d..349dc3e 100644
--- a/drivers/firmware/efi/arm-runtime.c
+++ b/drivers/firmware/efi/arm-runtime.c
@@ -39,7 +39,7 @@ static struct mm_struct efi_mm = {
.mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
};
-#ifdef CONFIG_ARM64_PTDUMP
+#ifdef CONFIG_ARM64_PTDUMP_DEBUGFS
#include <asm/ptdump.h>
static struct ptdump_info efi_ptdump_info = {
@@ -53,7 +53,7 @@ static struct ptdump_info efi_ptdump_info = {
static int __init ptdump_init(void)
{
- return ptdump_register(&efi_ptdump_info, "efi_page_tables");
+ return ptdump_debugfs_register(&efi_ptdump_info, "efi_page_tables");
}
device_initcall(ptdump_init);
--
2.7.4