powerpc/mm: Add support for handling > 512TB address in SLB miss

[mirror_ubuntu-focal-kernel.git] / arch / powerpc / include / asm / book3s / 64 / mmu.h

diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index c8c836e8ad1b0b66a45e356dfa5c438cc02edc8a..5094696eecd6d4a010b08f5a4ff2bfb0d76eee02 100644 (file)
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -91,7 +91,18 @@ struct slice_mask {
 };
 
 typedef struct {
-       mm_context_id_t id;
+       union {
+               /*
+                * We use id as the PIDR content for radix. On hash we can use
+                * more than one id. The extended ids are used when we start
+                * having address above 512TB. We allocate one extended id
+                * for each 512TB. The new id is then used with the 49 bit
+                * EA to build a new VA. We always use ESID_BITS_1T_MASK bits
+                * from EA and new context ids to build the new VAs.
+                */
+               mm_context_id_t id;
+               mm_context_id_t extended_id[TASK_SIZE_USER64/TASK_CONTEXT_SIZE];
+       };
        u16 user_psize;         /* page size index */
 
        /* Number of bits in the mm_cpumask */
@@ -196,5 +207,25 @@ extern void radix_init_pseries(void);
 static inline void radix_init_pseries(void) { };
 #endif
 
+static inline int get_ea_context(mm_context_t *ctx, unsigned long ea)
+{
+       int index = ea >> MAX_EA_BITS_PER_CONTEXT;
+
+       if (likely(index < ARRAY_SIZE(ctx->extended_id)))
+               return ctx->extended_id[index];
+
+       /* should never happen */
+       WARN_ON(1);
+       return 0;
+}
+
+static inline unsigned long get_user_vsid(mm_context_t *ctx,
+                                         unsigned long ea, int ssize)
+{
+       unsigned long context = get_ea_context(ctx, ea);
+
+       return get_vsid(context, ea, ssize);
+}
+
 #endif /* __ASSEMBLY__ */
 #endif /* _ASM_POWERPC_BOOK3S_64_MMU_H_ */