diff mbox

[v2,1/2] efi/x86: move UEFI Runtime Services wrappers to generic code

Message ID 1403777346-28629-2-git-send-email-ard.biesheuvel@linaro.org
State Superseded
Headers show

Commit Message

Ard Biesheuvel June 26, 2014, 10:09 a.m. UTC 
In order for other archs (such as arm64) to be able to reuse the virtual mode
function call wrappers, move them to drivers/firmware/efi/runtime-wrappers.c.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 arch/x86/Kconfig                        |   1 +
 arch/x86/platform/efi/efi.c             | 144 +---------------------------
 drivers/firmware/efi/Kconfig            |   7 ++
 drivers/firmware/efi/Makefile           |   1 +
 drivers/firmware/efi/runtime-wrappers.c | 161 ++++++++++++++++++++++++++++++++
 include/linux/efi.h                     |   2 +
 6 files changed, 174 insertions(+), 142 deletions(-)
 create mode 100644 drivers/firmware/efi/runtime-wrappers.c

Comments

Matt Fleming July 1, 2014, 1:30 p.m. UTC | #1 
On Thu, 26 Jun, at 12:09:05PM, Ard Biesheuvel wrote:
> In order for other archs (such as arm64) to be able to reuse the virtual mode
> function call wrappers, move them to drivers/firmware/efi/runtime-wrappers.c.
> 
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

[...]

> @@ -54,6 +54,13 @@ config EFI_PARAMS_FROM_FDT
>  	  the EFI runtime support gets system table address, memory
>            map address, and other parameters from the device tree.
>  
> +config EFI_RUNTIME_WRAPPERS
> +	bool
> +	help
> +	  Selected by the arch if it needs to wrap UEFI Runtime Services calls,
> +	  in which case it needs to provide #definitions of efi_call_virt and
> +	  __efi_call_virt in <asm/efi.h>
> +
>  endmenu

Actually, could we drop this help text?

That may seem like a backwards step, but I have concerns that we'll fail
to keep this help text in sync with the code. Furthermore, by providing
help text that kinda says, "casual users need the help text to
understand when to enable this feature". Clearly that's not what this
Kconfig symbol is for.

Most of the other guard Kconfig symbols don't provide this kind of text,
and I think there's good reason to follow suit.

What do you think?
Ard Biesheuvel July 1, 2014, 1:35 p.m. UTC | #2 
On 1 July 2014 15:30, Matt Fleming <matt@console-pimps.org> wrote:
> On Thu, 26 Jun, at 12:09:05PM, Ard Biesheuvel wrote:
>> In order for other archs (such as arm64) to be able to reuse the virtual mode
>> function call wrappers, move them to drivers/firmware/efi/runtime-wrappers.c.
>>
>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>
> [...]
>
>> @@ -54,6 +54,13 @@ config EFI_PARAMS_FROM_FDT
>>         the EFI runtime support gets system table address, memory
>>            map address, and other parameters from the device tree.
>>
>> +config EFI_RUNTIME_WRAPPERS
>> +     bool
>> +     help
>> +       Selected by the arch if it needs to wrap UEFI Runtime Services calls,
>> +       in which case it needs to provide #definitions of efi_call_virt and
>> +       __efi_call_virt in <asm/efi.h>
>> +
>>  endmenu
>
> Actually, could we drop this help text?
>
> That may seem like a backwards step, but I have concerns that we'll fail
> to keep this help text in sync with the code. Furthermore, by providing
> help text that kinda says, "casual users need the help text to
> understand when to enable this feature". Clearly that's not what this
> Kconfig symbol is for.
>
> Most of the other guard Kconfig symbols don't provide this kind of text,
> and I think there's good reason to follow suit.
>
> What do you think?
>

I agree, but I kind of followed the example of the Kconfig symbols in
the vicinity.
So sure, rip it out. Or would you like me to do a v(n+1)?
Matt Fleming July 1, 2014, 1:48 p.m. UTC | #3 
On Tue, 01 Jul, at 03:35:09PM, Ard Biesheuvel wrote:
> 
> I agree, but I kind of followed the example of the Kconfig symbols in
> the vicinity.
> So sure, rip it out. Or would you like me to do a v(n+1)?

Thanks. Nah, no need for another version, I'ved fixed this up in 'next',
but please do check the commits to make sure nothing untoward has
occurred.
diff mbox

Patch

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index a8f749ef0fdc..4c3f026aa5ce 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1522,6 +1522,7 @@  config EFI
 	bool "EFI runtime service support"
 	depends on ACPI
 	select UCS2_STRING
+	select EFI_RUNTIME_WRAPPERS
 	---help---
 	  This enables the kernel to use EFI runtime services that are
 	  available (such as the EFI variable services).
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 87fc96bcc13c..36d0835210c3 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -104,130 +104,6 @@  static int __init setup_storage_paranoia(char *arg)
 }
 early_param("efi_no_storage_paranoia", setup_storage_paranoia);
 
-static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
-{
-	unsigned long flags;
-	efi_status_t status;
-
-	spin_lock_irqsave(&rtc_lock, flags);
-	status = efi_call_virt(get_time, tm, tc);
-	spin_unlock_irqrestore(&rtc_lock, flags);
-	return status;
-}
-
-static efi_status_t virt_efi_set_time(efi_time_t *tm)
-{
-	unsigned long flags;
-	efi_status_t status;
-
-	spin_lock_irqsave(&rtc_lock, flags);
-	status = efi_call_virt(set_time, tm);
-	spin_unlock_irqrestore(&rtc_lock, flags);
-	return status;
-}
-
-static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
-					     efi_bool_t *pending,
-					     efi_time_t *tm)
-{
-	unsigned long flags;
-	efi_status_t status;
-
-	spin_lock_irqsave(&rtc_lock, flags);
-	status = efi_call_virt(get_wakeup_time, enabled, pending, tm);
-	spin_unlock_irqrestore(&rtc_lock, flags);
-	return status;
-}
-
-static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
-{
-	unsigned long flags;
-	efi_status_t status;
-
-	spin_lock_irqsave(&rtc_lock, flags);
-	status = efi_call_virt(set_wakeup_time, enabled, tm);
-	spin_unlock_irqrestore(&rtc_lock, flags);
-	return status;
-}
-
-static efi_status_t virt_efi_get_variable(efi_char16_t *name,
-					  efi_guid_t *vendor,
-					  u32 *attr,
-					  unsigned long *data_size,
-					  void *data)
-{
-	return efi_call_virt(get_variable,
-			     name, vendor, attr,
-			     data_size, data);
-}
-
-static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
-					       efi_char16_t *name,
-					       efi_guid_t *vendor)
-{
-	return efi_call_virt(get_next_variable,
-			     name_size, name, vendor);
-}
-
-static efi_status_t virt_efi_set_variable(efi_char16_t *name,
-					  efi_guid_t *vendor,
-					  u32 attr,
-					  unsigned long data_size,
-					  void *data)
-{
-	return efi_call_virt(set_variable,
-			     name, vendor, attr,
-			     data_size, data);
-}
-
-static efi_status_t virt_efi_query_variable_info(u32 attr,
-						 u64 *storage_space,
-						 u64 *remaining_space,
-						 u64 *max_variable_size)
-{
-	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
-		return EFI_UNSUPPORTED;
-
-	return efi_call_virt(query_variable_info, attr, storage_space,
-			     remaining_space, max_variable_size);
-}
-
-static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
-{
-	return efi_call_virt(get_next_high_mono_count, count);
-}
-
-static void virt_efi_reset_system(int reset_type,
-				  efi_status_t status,
-				  unsigned long data_size,
-				  efi_char16_t *data)
-{
-	__efi_call_virt(reset_system, reset_type, status,
-			data_size, data);
-}
-
-static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
-					    unsigned long count,
-					    unsigned long sg_list)
-{
-	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
-		return EFI_UNSUPPORTED;
-
-	return efi_call_virt(update_capsule, capsules, count, sg_list);
-}
-
-static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
-						unsigned long count,
-						u64 *max_size,
-						int *reset_type)
-{
-	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
-		return EFI_UNSUPPORTED;
-
-	return efi_call_virt(query_capsule_caps, capsules, count, max_size,
-			     reset_type);
-}
-
 static efi_status_t __init phys_efi_set_virtual_address_map(
 	unsigned long memory_map_size,
 	unsigned long descriptor_size,
@@ -847,22 +723,6 @@  void __init old_map_region(efi_memory_desc_t *md)
 		       (unsigned long long)md->phys_addr);
 }
 
-static void native_runtime_setup(void)
-{
-	efi.get_time = virt_efi_get_time;
-	efi.set_time = virt_efi_set_time;
-	efi.get_wakeup_time = virt_efi_get_wakeup_time;
-	efi.set_wakeup_time = virt_efi_set_wakeup_time;
-	efi.get_variable = virt_efi_get_variable;
-	efi.get_next_variable = virt_efi_get_next_variable;
-	efi.set_variable = virt_efi_set_variable;
-	efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
-	efi.reset_system = virt_efi_reset_system;
-	efi.query_variable_info = virt_efi_query_variable_info;
-	efi.update_capsule = virt_efi_update_capsule;
-	efi.query_capsule_caps = virt_efi_query_capsule_caps;
-}
-
 /* Merge contiguous regions of the same type and attribute */
 static void __init efi_merge_regions(void)
 {
@@ -1049,7 +909,7 @@  static void __init kexec_enter_virtual_mode(void)
 	 */
 	efi.runtime_version = efi_systab.hdr.revision;
 
-	native_runtime_setup();
+	efi_native_runtime_setup();
 
 	efi.set_virtual_address_map = NULL;
 
@@ -1142,7 +1002,7 @@  static void __init __efi_enter_virtual_mode(void)
 	efi.runtime_version = efi_systab.hdr.revision;
 
 	if (efi_is_native())
-		native_runtime_setup();
+		efi_native_runtime_setup();
 	else
 		efi_thunk_runtime_setup();
 
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index d420ae2d3413..04a7af46736a 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -54,6 +54,13 @@  config EFI_PARAMS_FROM_FDT
 	  the EFI runtime support gets system table address, memory
           map address, and other parameters from the device tree.
 
+config EFI_RUNTIME_WRAPPERS
+	bool
+	help
+	  Selected by the arch if it needs to wrap UEFI Runtime Services calls,
+	  in which case it needs to provide #definitions of efi_call_virt and
+	  __efi_call_virt in <asm/efi.h>
+
 endmenu
 
 config UEFI_CPER
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index 9553496b0f43..e1096539eedb 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -6,3 +6,4 @@  obj-$(CONFIG_EFI_VARS)			+= efivars.o
 obj-$(CONFIG_EFI_VARS_PSTORE)		+= efi-pstore.o
 obj-$(CONFIG_UEFI_CPER)			+= cper.o
 obj-$(CONFIG_EFI_RUNTIME_MAP)		+= runtime-map.o
+obj-$(CONFIG_EFI_RUNTIME_WRAPPERS)	+= runtime-wrappers.o
diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c
new file mode 100644
index 000000000000..10daa4bbb258
--- /dev/null
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -0,0 +1,161 @@ 
+/*
+ * runtime-wrappers.c - Runtime Services function call wrappers
+ *
+ * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ *
+ * Split off from arch/x86/platform/efi/efi.c
+ *
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ * Copyright (C) 1999-2002 Hewlett-Packard Co.
+ * Copyright (C) 2005-2008 Intel Co.
+ * Copyright (C) 2013 SuSE Labs
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/efi.h>
+#include <linux/spinlock.h>             /* spinlock_t */
+#include <asm/efi.h>
+
+/*
+ * As per commit ef68c8f87ed1 ("x86: Serialize EFI time accesses on rtc_lock"),
+ * the EFI specification requires that callers of the time related runtime
+ * functions serialize with other CMOS accesses in the kernel, as the EFI time
+ * functions may choose to also use the legacy CMOS RTC.
+ */
+__weak DEFINE_SPINLOCK(rtc_lock);
+
+static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	status = efi_call_virt(get_time, tm, tc);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_set_time(efi_time_t *tm)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	status = efi_call_virt(set_time, tm);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
+					     efi_bool_t *pending,
+					     efi_time_t *tm)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	status = efi_call_virt(get_wakeup_time, enabled, pending, tm);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
+{
+	unsigned long flags;
+	efi_status_t status;
+
+	spin_lock_irqsave(&rtc_lock, flags);
+	status = efi_call_virt(set_wakeup_time, enabled, tm);
+	spin_unlock_irqrestore(&rtc_lock, flags);
+	return status;
+}
+
+static efi_status_t virt_efi_get_variable(efi_char16_t *name,
+					  efi_guid_t *vendor,
+					  u32 *attr,
+					  unsigned long *data_size,
+					  void *data)
+{
+	return efi_call_virt(get_variable, name, vendor, attr, data_size, data);
+}
+
+static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
+					       efi_char16_t *name,
+					       efi_guid_t *vendor)
+{
+	return efi_call_virt(get_next_variable, name_size, name, vendor);
+}
+
+static efi_status_t virt_efi_set_variable(efi_char16_t *name,
+					  efi_guid_t *vendor,
+					  u32 attr,
+					  unsigned long data_size,
+					  void *data)
+{
+	return efi_call_virt(set_variable, name, vendor, attr, data_size, data);
+}
+
+static efi_status_t virt_efi_query_variable_info(u32 attr,
+						 u64 *storage_space,
+						 u64 *remaining_space,
+						 u64 *max_variable_size)
+{
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	return efi_call_virt(query_variable_info, attr, storage_space,
+			     remaining_space, max_variable_size);
+}
+
+static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
+{
+	return efi_call_virt(get_next_high_mono_count, count);
+}
+
+static void virt_efi_reset_system(int reset_type,
+				  efi_status_t status,
+				  unsigned long data_size,
+				  efi_char16_t *data)
+{
+	__efi_call_virt(reset_system, reset_type, status, data_size, data);
+}
+
+static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
+					    unsigned long count,
+					    unsigned long sg_list)
+{
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	return efi_call_virt(update_capsule, capsules, count, sg_list);
+}
+
+static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
+						unsigned long count,
+						u64 *max_size,
+						int *reset_type)
+{
+	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
+		return EFI_UNSUPPORTED;
+
+	return efi_call_virt(query_capsule_caps, capsules, count, max_size,
+			     reset_type);
+}
+
+void efi_native_runtime_setup(void)
+{
+	efi.get_time = virt_efi_get_time;
+	efi.set_time = virt_efi_set_time;
+	efi.get_wakeup_time = virt_efi_get_wakeup_time;
+	efi.set_wakeup_time = virt_efi_set_wakeup_time;
+	efi.get_variable = virt_efi_get_variable;
+	efi.get_next_variable = virt_efi_get_next_variable;
+	efi.set_variable = virt_efi_set_variable;
+	efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
+	efi.reset_system = virt_efi_reset_system;
+	efi.query_variable_info = virt_efi_query_variable_info;
+	efi.update_capsule = virt_efi_update_capsule;
+	efi.query_capsule_caps = virt_efi_query_capsule_caps;
+}
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 41bbf8ba4ba8..0ceb816bdfc2 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -521,6 +521,8 @@  typedef efi_status_t efi_query_capsule_caps_t(efi_capsule_header_t **capsules,
 					      int *reset_type);
 typedef efi_status_t efi_query_variable_store_t(u32 attributes, unsigned long size);
 
+void efi_native_runtime_setup(void);
+
 /*
  *  EFI Configuration Table and GUID definitions
  */