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 <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Minor formatting tweaks and comment wording, switch BUG to WARN
      in get_ea_context().]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Aneesh Kumar K.V 2018-03-26 15:34:48 +05:30 committed by Michael Ellerman
parent 0dea04b288
commit f384796c40
15 changed files with 246 additions and 28 deletions

View file

@ -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)