From: Mike Rapoport <rppt@xxxxxxxxxxxxx> Subject: openrisc: add support for folded p4d page tables Implement primitives necessary for the 4th level folding, add walks of p4d level where appropriate and remove usage of __ARCH_USE_5LEVEL_HACK. Link: http://lkml.kernel.org/r/20200414153455.21744-8-rppt@xxxxxxxxxx Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Brian Cain <bcain@xxxxxxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Christophe Leroy <christophe.leroy@xxxxxx> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> Cc: Guan Xuetao <gxt@xxxxxxxxxx> Cc: James Morse <james.morse@xxxxxxx> Cc: Jonas Bonn <jonas@xxxxxxxxxxxx> Cc: Julien Thierry <julien.thierry.kdev@xxxxxxxxx> Cc: Ley Foon Tan <ley.foon.tan@xxxxxxxxx> Cc: Marc Zyngier <maz@xxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxx> Cc: Stafford Horne <shorne@xxxxxxxxx> Cc: Stefan Kristiansson <stefan.kristiansson@xxxxxxxxxxxxx> Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/openrisc/include/asm/pgtable.h | 1 - arch/openrisc/mm/fault.c | 10 ++++++++-- arch/openrisc/mm/init.c | 4 +++- 3 files changed, 11 insertions(+), 4 deletions(-) --- a/arch/openrisc/include/asm/pgtable.h~openrisc-add-support-for-folded-p4d-page-tables +++ a/arch/openrisc/include/asm/pgtable.h @@ -21,7 +21,6 @@ #ifndef __ASM_OPENRISC_PGTABLE_H #define __ASM_OPENRISC_PGTABLE_H -#define __ARCH_USE_5LEVEL_HACK #include <asm-generic/pgtable-nopmd.h> #ifndef __ASSEMBLY__ --- a/arch/openrisc/mm/fault.c~openrisc-add-support-for-folded-p4d-page-tables +++ a/arch/openrisc/mm/fault.c @@ -295,6 +295,7 @@ vmalloc_fault: int offset = pgd_index(address); pgd_t *pgd, *pgd_k; + p4d_t *p4d, *p4d_k; pud_t *pud, *pud_k; pmd_t *pmd, *pmd_k; pte_t *pte_k; @@ -321,8 +322,13 @@ vmalloc_fault: * it exists. */ - pud = pud_offset(pgd, address); - pud_k = pud_offset(pgd_k, address); + p4d = p4d_offset(pgd, address); + p4d_k = p4d_offset(pgd_k, address); + if (!p4d_present(*p4d_k)) + goto no_context; + + pud = pud_offset(p4d, address); + pud_k = pud_offset(p4d_k, address); if (!pud_present(*pud_k)) goto no_context; --- a/arch/openrisc/mm/init.c~openrisc-add-support-for-folded-p4d-page-tables +++ a/arch/openrisc/mm/init.c @@ -68,6 +68,7 @@ static void __init map_ram(void) unsigned long v, p, e; pgprot_t prot; pgd_t *pge; + p4d_t *p4e; pud_t *pue; pmd_t *pme; pte_t *pte; @@ -87,7 +88,8 @@ static void __init map_ram(void) while (p < e) { int j; - pue = pud_offset(pge, v); + p4e = p4d_offset(pge, v); + pue = pud_offset(p4e, v); pme = pmd_offset(pue, v); if ((u32) pue != (u32) pge || (u32) pme != (u32) pge) { _
