efi: Use correct type for struct efi_memory_map::phys_map

We have been getting away with using a void* for the physical
address of the UEFI memory map, since, even on 32-bit platforms
with 64-bit physical addresses, no truncation takes place if the
memory map has been allocated by the firmware (which only uses
1:1 virtually addressable memory), which is usually the case.

However, commit:

  0f96a99dab36 ("efi: Add "efi_fake_mem" boot option")

adds code that clones and modifies the UEFI memory map, and the
clone may live above 4 GB on 32-bit platforms.

This means our use of void* for struct efi_memory_map::phys_map has
graduated from 'incorrect but working' to 'incorrect and
broken', and we need to fix it.

So redefine struct efi_memory_map::phys_map as phys_addr_t, and
get rid of a bunch of casts that are now unneeded.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: izumi.taku@jp.fujitsu.com
Cc: kamezawa.hiroyu@jp.fujitsu.com
Cc: linux-efi@vger.kernel.org
Cc: matt.fleming@intel.com
Link: http://lkml.kernel.org/r/1445593697-1342-1-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 3e1d09e885c0..ad285404ea7f 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -194,7 +194,7 @@ static void __init do_add_efi_memmap(void)
 int __init efi_memblock_x86_reserve_range(void)
 {
         struct efi_info *e = &boot_params.efi_info;
-        unsigned long pmap;
+        phys_addr_t pmap;
 
         if (efi_enabled(EFI_PARAVIRT))
                 return 0;
@@ -209,7 +209,7 @@ int __init efi_memblock_x86_reserve_range(void)
 #else
         pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
 #endif
-        memmap.phys_map         = (void *)pmap;
+        memmap.phys_map         = pmap;
         memmap.nr_map           = e->efi_memmap_size /
                                   e->efi_memdesc_size;
         memmap.desc_size        = e->efi_memdesc_size;