Revert "convert SLB miss handlers to C" and subsequent commits

This reverts commits:
  5e46e29e6a97 ("powerpc/64s/hash: convert SLB miss handlers to C")
  8fed04d0f6ae ("powerpc/64s/hash: remove user SLB data from the paca")
  655deecf67b2 ("powerpc/64s/hash: SLB allocation status bitmaps")
  2e1626744e8d ("powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setup")
  89ca4e126a3f ("powerpc/64s/hash: Add a SLB preload cache")

This series had a few bugs, and the fixes are not all trivial. So
revert most of it for now.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 22 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
index 0cf84e30d1cd..0ee3e6d50f28 100644
--- a/arch/powerpc/kernel/paca.c
+++ b/arch/powerpc/kernel/paca.c
@@ -258,3 +258,25 @@ void __init free_unused_pacas(void)
 	printk(KERN_DEBUG "Allocated %u bytes for %u pacas\n",
 			paca_ptrs_size + paca_struct_size, nr_cpu_ids);
 }
+
+void copy_mm_to_paca(struct mm_struct *mm)
+{
+#ifdef CONFIG_PPC_BOOK3S
+	mm_context_t *context = &mm->context;
+
+	get_paca()->mm_ctx_id = context->id;
+#ifdef CONFIG_PPC_MM_SLICES
+	VM_BUG_ON(!mm->context.slb_addr_limit);
+	get_paca()->mm_ctx_slb_addr_limit = mm->context.slb_addr_limit;
+	memcpy(&get_paca()->mm_ctx_low_slices_psize,
+	       &context->low_slices_psize, sizeof(context->low_slices_psize));
+	memcpy(&get_paca()->mm_ctx_high_slices_psize,
+	       &context->high_slices_psize, TASK_SLICE_ARRAY_SZ(mm));
+#else /* CONFIG_PPC_MM_SLICES */
+	get_paca()->mm_ctx_user_psize = context->user_psize;
+	get_paca()->mm_ctx_sllp = context->sllp;
+#endif
+#else /* !CONFIG_PPC_BOOK3S */
+	return;
+#endif
+}