[PATCH 1/2] Create UV efi_call macros

Alex Thorlton
2016-05-11T19:55:44Z

We need a slightly different macro than the standard efi_call_virt,
since those macros all assume that the function pointer, f, that gets
passed in will live somewhere in efi.systab->runtime. Our EFI function
pointer lives in efi.uv_systab, so we can't use the standard macros out
of the box.

This commit creates some new uv_* macros that are functionally
equivalent to the standard ones, with the exception of allowing us to
use a different function pointer. I figure that we won't want to call
these uv_* in the end (we'll probably want something more generic), but
I thought I would get everyone's thoughts on how we might best reach
that goal instead of just trying to come up with a new implementation on
my own.

By itself, this commit does get our machines booting, but it needs the
small fix to the efi_call assembly code for our modules to work.

Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Russ Anderson <rja@sgi.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: linux-efi@vger.kernel.org
---
arch/x86/include/asm/efi.h | 3 ++
arch/x86/platform/uv/bios_uv.c | 3 +-
drivers/firmware/efi/runtime-wrappers.c | 44 +-------------------------
include/linux/efi.h | 55 +++++++++++++++++++++++++++++++++
4 files changed, 60 insertions(+), 45 deletions(-)

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 78d1e74..f384047 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -84,6 +84,9 @@ struct efi_scratch {
#define arch_efi_call_virt(f, args...) \
efi_call((void *)efi.systab->runtime->f, args) \

+#define uv_efi_call_virt(f, args...) \
+ efi_call((void *)f, args) \
+
#define arch_efi_call_virt_teardown() \
({ \
if (efi_scratch.use_pgd) { \
diff --git a/arch/x86/platform/uv/bios_uv.c b/arch/x86/platform/uv/bios_uv.c
index 815fec6..62a46cb 100644
--- a/arch/x86/platform/uv/bios_uv.c
+++ b/arch/x86/platform/uv/bios_uv.c
@@ -40,8 +40,7 @@ s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5)
*/
return BIOS_STATUS_UNIMPLEMENTED;

- ret = efi_call((void *)__va(tab->function), (u64)which,
- a1, a2, a3, a4, a5);
+ ret = uv_call_virt(tab->function, (u64)which, a1, a2, a3, a4, a5);
return ret;
}
EXPORT_SYMBOL_GPL(uv_bios_call);
diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c
index 23bef6b..008a1a3 100644
--- a/drivers/firmware/efi/runtime-wrappers.c
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -22,7 +22,7 @@
#include <linux/stringify.h>
#include <asm/efi.h>

-static void efi_call_virt_check_flags(unsigned long flags, const char *call)
+void efi_call_virt_check_flags(unsigned long flags, const char *call)
{
unsigned long cur_flags, mismatch;

@@ -39,48 +39,6 @@ static void efi_call_virt_check_flags(unsigned long flags, const char *call)
}

/*
- * Arch code can implement the following three template macros, avoiding
- * reptition for the void/non-void return cases of {__,}efi_call_virt:
- *
- * * arch_efi_call_virt_setup
- *
- * Sets up the environment for the call (e.g. switching page tables,
- * allowing kernel-mode use of floating point, if required).
- *
- * * arch_efi_call_virt
- *
- * Performs the call. The last expression in the macro must be the call
- * itself, allowing the logic to be shared by the void and non-void
- * cases.
- *
- * * arch_efi_call_virt_teardown
- *
- * Restores the usual kernel environment once the call has returned.
- */
-
-#define efi_call_virt(f, args...) \
-({ \
- efi_status_t __s; \
- unsigned long flags; \
- arch_efi_call_virt_setup(); \
- local_save_flags(flags); \
- __s = arch_efi_call_virt(f, args); \
- efi_call_virt_check_flags(flags, __stringify(f)); \
- arch_efi_call_virt_teardown(); \
- __s; \
-})
-
-#define __efi_call_virt(f, args...) \
-({ \
- unsigned long flags; \
- arch_efi_call_virt_setup(); \
- local_save_flags(flags); \
- arch_efi_call_virt(f, args); \
- efi_call_virt_check_flags(flags, __stringify(f)); \
- arch_efi_call_virt_teardown(); \
-})
-
-/*
* According to section 7.1 of the UEFI spec, Runtime Services are not fully
* reentrant, and there are particular combinations of calls that need to be
* serialized. (source: UEFI Specification v2.4A)
diff --git a/include/linux/efi.h b/include/linux/efi.h
index df7acb5..f429269 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1471,4 +1471,59 @@ efi_status_t efi_setup_gop(efi_system_table_t *sys_table_arg,
unsigned long size);

bool efi_runtime_disabled(void);
+extern void efi_call_virt_check_flags(unsigned long flags, const char *call);
+
+/*
+ * Arch code can implement the following three template macros, avoiding
+ * reptition for the void/non-void return cases of {__,}efi_call_virt:
+ *
+ * * arch_efi_call_virt_setup
+ *
+ * Sets up the environment for the call (e.g. switching page tables,
+ * allowing kernel-mode use of floating point, if required).
+ *
+ * * arch_efi_call_virt
+ *
+ * Performs the call. The last expression in the macro must be the call
+ * itself, allowing the logic to be shared by the void and non-void
+ * cases.
+ *
+ * * arch_efi_call_virt_teardown
+ *
+ * Restores the usual kernel environment once the call has returned.
+ */
+
+#define efi_call_virt(f, args...) \
+({ \
+ efi_status_t __s; \
+ unsigned long flags; \
+ arch_efi_call_virt_setup(); \
+ local_save_flags(flags); \
+ __s = arch_efi_call_virt(f, args); \
+ efi_call_virt_check_flags(flags, __stringify(f)); \
+ arch_efi_call_virt_teardown(); \
+ __s; \
+})
+
+#define __efi_call_virt(f, args...) \
+({ \
+ unsigned long flags; \
+ arch_efi_call_virt_setup(); \
+ local_save_flags(flags); \
+ arch_efi_call_virt(f, args); \
+ efi_call_virt_check_flags(flags, __stringify(f)); \
+ arch_efi_call_virt_teardown(); \
+})
+
+#define uv_call_virt(f, args...) \
+({ \
+ efi_status_t __s; \
+ unsigned long flags; \
+ arch_efi_call_virt_setup(); \
+ local_save_flags(flags); \
+ __s = uv_efi_call_virt(f, args); \
+ efi_call_virt_check_flags(flags, __stringify(f)); \
+ arch_efi_call_virt_teardown(); \
+ __s; \
+})
#endif /* _LINUX_EFI_H */
--
1.8.5.6