Re: [PATCH v5 08/14] efi: export efi runtime memory mapping to sysfs

From: Dave Young
Date: Fri Dec 13 2013 - 02:27:07 EST


On 12/12/13 at 09:53pm, Borislav Petkov wrote:
> On Thu, Dec 12, 2013 at 10:36:17AM +0800, Dave Young wrote:
> > Sorry that I forgot to explain this in changelog, should ask you before.
> >
> > I did try moving it to efisubsys_init but it need add extern declaration
>
> So what? Add it.
>
> > for efi_runtime_map_init. Since link order will ensure it being called after
> > efisubsys_init I think it's fine with this static function.
>
> This is actually exactly the reason why it shouldn't be another
> subsys_initcall() if it can be helped. People would need to go have a
> look at drivers/firmware/efi/Makefile to realize that the link order is
> ok.
>
> And, this is prone to future breakage if people go and move code around
> and thereby change the link order.
>
> Please call efi_runtime_map_init from efisubsys_init.

After moving to efisubsys_init, the code will looks like below, because
the funtion only is used in drivers/firmware/efi/efi.c thus I can not
add a blank function in #else section in the efi.h header file. Creating
another header file for this one function looks bad to me.

Is below changes fine to you? I can add it to next version if you like it.

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 9fbaeb2..2db7ea5 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -133,6 +133,10 @@ extern void efi_sync_low_kernel_mappings(void);
extern void efi_setup_page_tables(void);
extern void __init old_map_region(efi_memory_desc_t *md);

+#ifdef CONFIG_EFI_RUNTIME_MAP
+extern int __init efi_runtime_map_init(void);
+#endif
+
#ifdef CONFIG_EFI

static inline bool efi_is_native(void)
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index afd0b49..85fd904 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -168,6 +168,12 @@ static int __init efisubsys_init(void)
goto err_unregister;
}

+#ifdef CONFIG_EFI_RUNTIME_MAP
+ error = efi_runtime_map_init();
+ if (error)
+ goto err_remove_group;
+#endif
+
/* and the standard mountpoint for efivarfs */
efivars_kobj = kobject_create_and_add("efivars", efi_kobj);
if (!efivars_kobj) {
diff --git a/drivers/firmware/efi/runtime-map.c b/drivers/firmware/efi/runtime-map.c
index e5e9984..5af06ad 100644
--- a/drivers/firmware/efi/runtime-map.c
+++ b/drivers/firmware/efi/runtime-map.c
@@ -135,7 +135,7 @@ static struct efi_runtime_map_entry *add_sysfs_runtime_map_entry(int nr)
return entry;
}

-static int __init efi_runtime_map_init(void)
+int __init efi_runtime_map_init(void)
{
int i, j, ret = 0;
struct efi_runtime_map_entry *entry;
@@ -172,5 +172,3 @@ out_add_entry:
out:
return ret;
}
-
-subsys_initcall(efi_runtime_map_init);

--
Thanks
Dave
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/