[PATCH v2 1/4] arm: mm: use strict p[gum]d types

From: Miles Chen
Date: Fri Oct 23 2020 - 05:15:10 EST


When use mm/gup.c, it is necessary to use strict p*d types.
Otherwise, we will get build breaks such as:

mm/gup.c:2589:9: error: incompatible pointer types passing 'pmdval_t **'
(aka 'unsigned int **') to parameter of type 'pgd_t *'
(aka 'pmdval_t (*)[2]') [-Werror,-Wincompatible-pointer-types]
mm/gup.c:2616:9: error: array initializer must be an initializer list

Fix some types errors in fixmap.h after using strict types.

Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Signed-off-by: Miles Chen <miles.chen@xxxxxxxxxxxx>
---
arch/arm/include/asm/fixmap.h | 6 ++---
arch/arm/include/asm/pgtable-2level-types.h | 26 ---------------------
arch/arm/include/asm/pgtable-2level.h | 1 +
3 files changed, 4 insertions(+), 29 deletions(-)

diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h
index fc56fc3e1931..3ea12b2da708 100644
--- a/arch/arm/include/asm/fixmap.h
+++ b/arch/arm/include/asm/fixmap.h
@@ -42,11 +42,11 @@ static const enum fixed_addresses __end_of_fixed_addresses =

#define FIXMAP_PAGE_COMMON (L_PTE_YOUNG | L_PTE_PRESENT | L_PTE_XN | L_PTE_DIRTY)

-#define FIXMAP_PAGE_NORMAL (pgprot_kernel | L_PTE_XN)
-#define FIXMAP_PAGE_RO (FIXMAP_PAGE_NORMAL | L_PTE_RDONLY)
+#define FIXMAP_PAGE_NORMAL __pgprot(pgprot_val(pgprot_kernel) | L_PTE_XN)
+#define FIXMAP_PAGE_RO __pgprot(pgprot_val(FIXMAP_PAGE_NORMAL) | L_PTE_RDONLY)

/* Used by set_fixmap_(io|nocache), both meant for mapping a device */
-#define FIXMAP_PAGE_IO (FIXMAP_PAGE_COMMON | L_PTE_MT_DEV_SHARED | L_PTE_SHARED)
+#define FIXMAP_PAGE_IO __pgprot(FIXMAP_PAGE_COMMON | L_PTE_MT_DEV_SHARED | L_PTE_SHARED)
#define FIXMAP_PAGE_NOCACHE FIXMAP_PAGE_IO

#define __early_set_fixmap __set_fixmap
diff --git a/arch/arm/include/asm/pgtable-2level-types.h b/arch/arm/include/asm/pgtable-2level-types.h
index 650e793f4142..64fd5b8d9dc2 100644
--- a/arch/arm/include/asm/pgtable-2level-types.h
+++ b/arch/arm/include/asm/pgtable-2level-types.h
@@ -12,12 +12,6 @@
typedef u32 pteval_t;
typedef u32 pmdval_t;

-#undef STRICT_MM_TYPECHECKS
-
-#ifdef STRICT_MM_TYPECHECKS
-/*
- * These are used to make use of C type-checking..
- */
typedef struct { pteval_t pte; } pte_t;
typedef struct { pmdval_t pmd; } pmd_t;
typedef struct { pmdval_t pgd[2]; } pgd_t;
@@ -32,24 +26,4 @@ typedef struct { pteval_t pgprot; } pgprot_t;
#define __pmd(x) ((pmd_t) { (x) } )
#define __pgprot(x) ((pgprot_t) { (x) } )

-#else
-/*
- * .. while these make it easier on the compiler
- */
-typedef pteval_t pte_t;
-typedef pmdval_t pmd_t;
-typedef pmdval_t pgd_t[2];
-typedef pteval_t pgprot_t;
-
-#define pte_val(x) (x)
-#define pmd_val(x) (x)
-#define pgd_val(x) ((x)[0])
-#define pgprot_val(x) (x)
-
-#define __pte(x) (x)
-#define __pmd(x) (x)
-#define __pgprot(x) (x)
-
-#endif /* STRICT_MM_TYPECHECKS */
-
#endif /* _ASM_PGTABLE_2LEVEL_TYPES_H */
diff --git a/arch/arm/include/asm/pgtable-2level.h b/arch/arm/include/asm/pgtable-2level.h
index 3502c2f746ca..27a8635abea0 100644
--- a/arch/arm/include/asm/pgtable-2level.h
+++ b/arch/arm/include/asm/pgtable-2level.h
@@ -180,6 +180,7 @@
#define pud_none(pud) (0)
#define pud_bad(pud) (0)
#define pud_present(pud) (1)
+#define pud_page(pud) pmd_page(__pmd(pud_val(pud)))
#define pud_clear(pudp) do { } while (0)
#define set_pud(pud,pudp) do { } while (0)

--
2.18.0