diff mbox series

[v2,01/12] x86/ioremap: Selectively build arch override encryption functions

Message ID a4338245609a6be63b162e3516d3f6614db782a4.1628873970.git.thomas.lendacky@amd.com (mailing list archive)
State New, archived
Headers show
Series Implement generic prot_guest_has() helper function | expand

Commit Message

Tom Lendacky Aug. 13, 2021, 4:59 p.m. UTC
In prep for other uses of the prot_guest_has() function besides AMD's
memory encryption support, selectively build the AMD memory encryption
architecture override functions only when CONFIG_AMD_MEM_ENCRYPT=y. These
functions are:
- early_memremap_pgprot_adjust()
- arch_memremap_can_ram_remap()

Additionally, routines that are only invoked by these architecture
override functions can also be conditionally built. These functions are:
- memremap_should_map_decrypted()
- memremap_is_efi_data()
- memremap_is_setup_data()
- early_memremap_is_setup_data()

And finally, phys_mem_access_encrypted() is conditionally built as well,
but requires a static inline version of it when CONFIG_AMD_MEM_ENCRYPT is
not set.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
 arch/x86/include/asm/io.h | 8 ++++++++
 arch/x86/mm/ioremap.c     | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

Comments

Borislav Petkov Aug. 14, 2021, 3:25 p.m. UTC | #1
On Fri, Aug 13, 2021 at 11:59:20AM -0500, Tom Lendacky wrote:
> In prep for other uses of the prot_guest_has() function besides AMD's
> memory encryption support, selectively build the AMD memory encryption
> architecture override functions only when CONFIG_AMD_MEM_ENCRYPT=y. These
> functions are:
> - early_memremap_pgprot_adjust()
> - arch_memremap_can_ram_remap()
> 
> Additionally, routines that are only invoked by these architecture
> override functions can also be conditionally built. These functions are:
> - memremap_should_map_decrypted()
> - memremap_is_efi_data()
> - memremap_is_setup_data()
> - early_memremap_is_setup_data()
> 
> And finally, phys_mem_access_encrypted() is conditionally built as well,
> but requires a static inline version of it when CONFIG_AMD_MEM_ENCRYPT is
> not set.
> 
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: Dave Hansen <dave.hansen@linux.intel.com>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
> ---
>  arch/x86/include/asm/io.h | 8 ++++++++
>  arch/x86/mm/ioremap.c     | 2 +-
>  2 files changed, 9 insertions(+), 1 deletion(-)

LGTM.
diff mbox series

Patch

diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index 841a5d104afa..5c6a4af0b911 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -391,6 +391,7 @@  extern void arch_io_free_memtype_wc(resource_size_t start, resource_size_t size)
 #define arch_io_reserve_memtype_wc arch_io_reserve_memtype_wc
 #endif
 
+#ifdef CONFIG_AMD_MEM_ENCRYPT
 extern bool arch_memremap_can_ram_remap(resource_size_t offset,
 					unsigned long size,
 					unsigned long flags);
@@ -398,6 +399,13 @@  extern bool arch_memremap_can_ram_remap(resource_size_t offset,
 
 extern bool phys_mem_access_encrypted(unsigned long phys_addr,
 				      unsigned long size);
+#else
+static inline bool phys_mem_access_encrypted(unsigned long phys_addr,
+					     unsigned long size)
+{
+	return true;
+}
+#endif
 
 /**
  * iosubmit_cmds512 - copy data to single MMIO location, in 512-bit units
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 60ade7dd71bd..ccff76cedd8f 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -508,6 +508,7 @@  void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)
 	memunmap((void *)((unsigned long)addr & PAGE_MASK));
 }
 
+#ifdef CONFIG_AMD_MEM_ENCRYPT
 /*
  * Examine the physical address to determine if it is an area of memory
  * that should be mapped decrypted.  If the memory is not part of the
@@ -746,7 +747,6 @@  bool phys_mem_access_encrypted(unsigned long phys_addr, unsigned long size)
 	return arch_memremap_can_ram_remap(phys_addr, size, 0);
 }
 
-#ifdef CONFIG_AMD_MEM_ENCRYPT
 /* Remap memory with encryption */
 void __init *early_memremap_encrypted(resource_size_t phys_addr,
 				      unsigned long size)