From ec2640b114d535ba7d895b6ee353791d542f2407 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Mon, 7 Sep 2015 12:53:53 +0530 Subject: [PATCH] powerpc/mm: Disable hugepd for 64K page size. After commit e2b3d202d1dba8f3546ed28224ce485bc50010be ("powerpc: Switch 16GB and 16MB explicit hugepages to a different page table format"), we don't need to support is_hugepd() for 64K page size. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/page.h | 15 +++++++++++++++ arch/powerpc/mm/hugetlbpage.c | 19 +++++++++++++++++++ 2 files changed, 34 insertions(+) diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h index 73b58ff6c451..96534b4e5a64 100644 --- a/arch/powerpc/include/asm/page.h +++ b/arch/powerpc/include/asm/page.h @@ -364,6 +364,20 @@ typedef struct { signed long pd; } hugepd_t; #ifdef CONFIG_HUGETLB_PAGE #ifdef CONFIG_PPC_BOOK3S_64 +#ifdef CONFIG_PPC_64K_PAGES +/* + * With 64k page size, we have hugepage ptes in the pgd and pmd entries. We don't + * need to setup hugepage directory for them. Our pte and page directory format + * enable us to have this enabled. But to avoid errors when implementing new + * features disable hugepd for 64K. We enable a debug version here, So we catch + * wrong usage. + */ +#ifdef CONFIG_DEBUG_VM +extern int hugepd_ok(hugepd_t hpd); +#else +#define hugepd_ok(x) (0) +#endif +#else static inline int hugepd_ok(hugepd_t hpd) { /* @@ -372,6 +386,7 @@ static inline int hugepd_ok(hugepd_t hpd) */ return (((hpd.pd & 0x3) == 0x0) && ((hpd.pd & HUGEPD_SHIFT_MASK) != 0)); } +#endif #else static inline int hugepd_ok(hugepd_t hpd) { diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index 06c14523b787..f093828e8997 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -89,6 +89,25 @@ int pgd_huge(pgd_t pgd) */ return ((pgd_val(pgd) & 0x3) != 0x0); } + +#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_DEBUG_VM) +/* + * This enables us to catch the wrong page directory format + * Moved here so that we can use WARN() in the call. + */ +int hugepd_ok(hugepd_t hpd) +{ + bool is_hugepd; + + /* + * We should not find this format in page directory, warn otherwise. + */ + is_hugepd = (((hpd.pd & 0x3) == 0x0) && ((hpd.pd & HUGEPD_SHIFT_MASK) != 0)); + WARN(is_hugepd, "Found wrong page directory format\n"); + return 0; +} +#endif + #else int pmd_huge(pmd_t pmd) {