From f384796c40dc55b3dba25e0ee9c1afd98c6d24d1 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Mon, 26 Mar 2018 15:34:48 +0530 Subject: powerpc/mm: Add support for handling > 512TB address in SLB miss For addresses above 512TB we allocate additional mmu contexts. To make it all easy, addresses above 512TB are handled with IR/DR=1 and with stack frame setup. The mmu_context_t is also updated to track the new extended_ids. To support upto 4PB we need a total 8 contexts. Signed-off-by: Aneesh Kumar K.V [mpe: Minor formatting tweaks and comment wording, switch BUG to WARN in get_ea_context().] Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/mmu_context.h | 39 ++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) (limited to 'arch/powerpc/include/asm/mmu_context.h') diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h index 3a15b6db9501..1835ca1505d6 100644 --- a/arch/powerpc/include/asm/mmu_context.h +++ b/arch/powerpc/include/asm/mmu_context.h @@ -60,12 +60,51 @@ extern int hash__alloc_context_id(void); extern void hash__reserve_context_id(int id); extern void __destroy_context(int context_id); static inline void mmu_context_init(void) { } + +static inline int alloc_extended_context(struct mm_struct *mm, + unsigned long ea) +{ + int context_id; + + int index = ea >> MAX_EA_BITS_PER_CONTEXT; + + context_id = hash__alloc_context_id(); + if (context_id < 0) + return context_id; + + VM_WARN_ON(mm->context.extended_id[index]); + mm->context.extended_id[index] = context_id; + return context_id; +} + +static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea) +{ + int context_id; + + context_id = get_ea_context(&mm->context, ea); + if (!context_id) + return true; + return false; +} + #else extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk); extern unsigned long __init_new_context(void); extern void __destroy_context(unsigned long context_id); extern void mmu_context_init(void); +static inline int alloc_extended_context(struct mm_struct *mm, + unsigned long ea) +{ + /* non book3s_64 should never find this called */ + WARN_ON(1); + return -ENOMEM; +} + +static inline bool need_extra_context(struct mm_struct *mm, unsigned long ea) +{ + return false; +} #endif #if defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) && defined(CONFIG_PPC_RADIX_MMU) -- cgit