diff options
-rw-r--r-- | arch/powerpc/include/asm/book3s/64/mmu.h | 2 | ||||
-rw-r--r-- | arch/powerpc/mm/mmu_context_book3s64.c | 67 |
2 files changed, 45 insertions, 24 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h index 805d4105e9bb..cce434e7de06 100644 --- a/arch/powerpc/include/asm/book3s/64/mmu.h +++ b/arch/powerpc/include/asm/book3s/64/mmu.h @@ -65,6 +65,8 @@ extern struct patb_entry *partition_tb; * MAX_USER_CONTEXT * 16 bytes of space. */ #define PRTB_SIZE_SHIFT (CONTEXT_BITS + 4) +#define PRTB_ENTRIES (1ul << CONTEXT_BITS) + /* * Power9 currently only support 64K partition table size. */ diff --git a/arch/powerpc/mm/mmu_context_book3s64.c b/arch/powerpc/mm/mmu_context_book3s64.c index 981c3b02e46a..e5da551edde3 100644 --- a/arch/powerpc/mm/mmu_context_book3s64.c +++ b/arch/powerpc/mm/mmu_context_book3s64.c @@ -63,47 +63,66 @@ int hash__alloc_context_id(void) } EXPORT_SYMBOL_GPL(hash__alloc_context_id); -static int radix__init_new_context(struct mm_struct *mm, int index) +static int hash__init_new_context(struct mm_struct *mm) +{ + int index; + + index = hash__alloc_context_id(); + if (index < 0) + return index; + + /* + * The old code would re-promote on fork, we don't do that when using + * slices as it could cause problem promoting slices that have been + * forced down to 4K. + * + * For book3s we have MMU_NO_CONTEXT set to be ~0. Hence check + * explicitly against context.id == 0. This ensures that we properly + * initialize context slice details for newly allocated mm's (which will + * have id == 0) and don't alter context slice inherited via fork (which + * will have id != 0). + * + * We should not be calling init_new_context() on init_mm. Hence a + * check against 0 is OK. + */ + if (mm->context.id == 0) + slice_set_user_psize(mm, mmu_virtual_psize); + + subpage_prot_init_new_context(mm); + + return index; +} + +static int radix__init_new_context(struct mm_struct *mm) { unsigned long rts_field; + int index; + + index = alloc_context_id(1, PRTB_ENTRIES - 1); + if (index < 0) + return index; /* * set the process table entry, */ rts_field = radix__get_tree_size(); process_tb[index].prtb0 = cpu_to_be64(rts_field | __pa(mm->pgd) | RADIX_PGD_INDEX_SIZE); - return 0; + + return index; } int init_new_context(struct task_struct *tsk, struct mm_struct *mm) { int index; - index = hash__alloc_context_id(); + if (radix_enabled()) + index = radix__init_new_context(mm); + else + index = hash__init_new_context(mm); + if (index < 0) return index; - if (radix_enabled()) { - radix__init_new_context(mm, index); - } else { - - /* The old code would re-promote on fork, we don't do that - * when using slices as it could cause problem promoting slices - * that have been forced down to 4K - * - * For book3s we have MMU_NO_CONTEXT set to be ~0. Hence check - * explicitly against context.id == 0. This ensures that we - * properly initialize context slice details for newly allocated - * mm's (which will have id == 0) and don't alter context slice - * inherited via fork (which will have id != 0). - * - * We should not be calling init_new_context() on init_mm. Hence a - * check against 0 is ok. - */ - if (mm->context.id == 0) - slice_set_user_psize(mm, mmu_virtual_psize); - subpage_prot_init_new_context(mm); - } mm->context.id = index; #ifdef CONFIG_PPC_ICSWX mm->context.cop_lockp = kmalloc(sizeof(spinlock_t), GFP_KERNEL); |