[PATCH] x86/mm/sme: Fix definition of PMD_FLAGS_DEC_WP

From: Arvind Sankar
Date: Mon Nov 09 2020 - 12:35:48 EST


The PAT bit is in different locations for 4k and 2M/1G page table
entries.

Add a definition for _PAGE_LARGE_CACHE_MASK to represent the three
caching bits (PWT, PCD, PAT), similar to _PAGE_CACHE_MASK for 4k pages,
and use it in the definition of PMD_FLAGS_DEC_WP to get the correct PAT
index for write-protected pages.

Remove a duplication definition of _PAGE_PAT_LARGE.

Signed-off-by: Arvind Sankar <nivedita@xxxxxxxxxxxx>
---
arch/x86/include/asm/pgtable_types.h | 3 +--
arch/x86/mm/mem_encrypt_identity.c | 4 ++--
2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index 816b31c68550..f24d7ef8fffa 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -155,6 +155,7 @@ enum page_cache_mode {
#define _PAGE_ENC (_AT(pteval_t, sme_me_mask))

#define _PAGE_CACHE_MASK (_PAGE_PWT | _PAGE_PCD | _PAGE_PAT)
+#define _PAGE_LARGE_CACHE_MASK (_PAGE_PWT | _PAGE_PCD | _PAGE_PAT_LARGE)

#define _PAGE_NOCACHE (cachemode2protval(_PAGE_CACHE_MODE_UC))
#define _PAGE_CACHE_WP (cachemode2protval(_PAGE_CACHE_MODE_WP))
@@ -176,8 +177,6 @@ enum page_cache_mode {
#define __pgprot(x) ((pgprot_t) { (x) } )
#define __pg(x) __pgprot(x)

-#define _PAGE_PAT_LARGE (_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE)
-
#define PAGE_NONE __pg( 0| 0| 0|___A| 0| 0| 0|___G)
#define PAGE_SHARED __pg(__PP|__RW|_USR|___A|__NX| 0| 0| 0)
#define PAGE_SHARED_EXEC __pg(__PP|__RW|_USR|___A| 0| 0| 0| 0)
diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c
index 733b983f3a89..6c5eb6f3f14f 100644
--- a/arch/x86/mm/mem_encrypt_identity.c
+++ b/arch/x86/mm/mem_encrypt_identity.c
@@ -45,8 +45,8 @@
#define PMD_FLAGS_LARGE (__PAGE_KERNEL_LARGE_EXEC & ~_PAGE_GLOBAL)

#define PMD_FLAGS_DEC PMD_FLAGS_LARGE
-#define PMD_FLAGS_DEC_WP ((PMD_FLAGS_DEC & ~_PAGE_CACHE_MASK) | \
- (_PAGE_PAT | _PAGE_PWT))
+#define PMD_FLAGS_DEC_WP ((PMD_FLAGS_DEC & ~_PAGE_LARGE_CACHE_MASK) | \
+ (_PAGE_PAT_LARGE | _PAGE_PWT))

#define PMD_FLAGS_ENC (PMD_FLAGS_LARGE | _PAGE_ENC)

--
2.26.2