--- zzzz-none-000/linux-3.10.107/arch/powerpc/mm/mmu_context_nohash.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/powerpc/mm/mmu_context_nohash.c	2021-02-04 17:41:59.000000000 +0000
@@ -52,12 +52,15 @@
 #include <asm/mmu_context.h>
 #include <asm/tlbflush.h>
 
+#include "mmu_decl.h"
+
 static unsigned int first_context, last_context;
 static unsigned int next_context, nr_free_contexts;
 static unsigned long *context_map;
 static unsigned long *stale_map[NR_CPUS];
 static struct mm_struct **context_mm;
 static DEFINE_RAW_SPINLOCK(context_lock);
+static bool no_selective_tlbil;
 
 #define CTX_MAP_SIZE	\
 	(sizeof(unsigned long) * (last_context / BITS_PER_LONG + 1))
@@ -112,8 +115,10 @@
 		 */
 		for_each_cpu(cpu, mm_cpumask(mm)) {
 			for (i = cpu_first_thread_sibling(cpu);
-			     i <= cpu_last_thread_sibling(cpu); i++)
-				__set_bit(id, stale_map[i]);
+			     i <= cpu_last_thread_sibling(cpu); i++) {
+				if (stale_map[i])
+					__set_bit(id, stale_map[i]);
+			}
 			cpu = i - 1;
 		}
 		return id;
@@ -131,6 +136,38 @@
 }
 #endif  /* CONFIG_SMP */
 
+static unsigned int steal_all_contexts(void)
+{
+	struct mm_struct *mm;
+	int cpu = smp_processor_id();
+	unsigned int id;
+
+	for (id = first_context; id <= last_context; id++) {
+		/* Pick up the victim mm */
+		mm = context_mm[id];
+
+		pr_hardcont(" | steal %d from 0x%p", id, mm);
+
+		/* Mark this mm as having no context anymore */
+		mm->context.id = MMU_NO_CONTEXT;
+		if (id != first_context) {
+			context_mm[id] = NULL;
+			__clear_bit(id, context_map);
+#ifdef DEBUG_MAP_CONSISTENCY
+			mm->context.active = 0;
+#endif
+		}
+		__clear_bit(id, stale_map[cpu]);
+	}
+
+	/* Flush the TLB for all contexts (not to be used on SMP) */
+	_tlbil_all();
+
+	nr_free_contexts = last_context - first_context;
+
+	return first_context;
+}
+
 /* Note that this will also be called on SMP if all other CPUs are
  * offlined, which means that it may be called for cpu != 0. For
  * this to work, we somewhat assume that CPUs that are onlined
@@ -239,7 +276,10 @@
 			goto stolen;
 		}
 #endif /* CONFIG_SMP */
-		id = steal_context_up(id);
+		if (no_selective_tlbil)
+			id = steal_all_contexts();
+		else
+			id = steal_context_up(id);
 		goto stolen;
 	}
 	nr_free_contexts--;
@@ -272,7 +312,8 @@
 		/* XXX This clear should ultimately be part of local_flush_tlb_mm */
 		for (i = cpu_first_thread_sibling(cpu);
 		     i <= cpu_last_thread_sibling(cpu); i++) {
-			__clear_bit(id, stale_map[i]);
+			if (stale_map[i])
+				__clear_bit(id, stale_map[i]);
 		}
 	}
 
@@ -329,8 +370,8 @@
 
 #ifdef CONFIG_SMP
 
-static int __cpuinit mmu_context_cpu_notify(struct notifier_block *self,
-					    unsigned long action, void *hcpu)
+static int mmu_context_cpu_notify(struct notifier_block *self,
+				  unsigned long action, void *hcpu)
 {
 	unsigned int cpu = (unsigned int)(long)hcpu;
 
@@ -363,7 +404,7 @@
 	return NOTIFY_OK;
 }
 
-static struct notifier_block __cpuinitdata mmu_context_cpu_nb = {
+static struct notifier_block mmu_context_cpu_nb = {
 	.notifier_call	= mmu_context_cpu_notify,
 };
 
@@ -404,22 +445,15 @@
 	if (mmu_has_feature(MMU_FTR_TYPE_8xx)) {
 		first_context = 0;
 		last_context = 15;
+		no_selective_tlbil = true;
 	} else if (mmu_has_feature(MMU_FTR_TYPE_47x)) {
 		first_context = 1;
 		last_context = 65535;
-	} else
-#ifdef CONFIG_PPC_BOOK3E_MMU
-	if (mmu_has_feature(MMU_FTR_TYPE_3E)) {
-		u32 mmucfg = mfspr(SPRN_MMUCFG);
-		u32 pid_bits = (mmucfg & MMUCFG_PIDSIZE_MASK)
-				>> MMUCFG_PIDSIZE_SHIFT;
-		first_context = 1;
-		last_context = (1UL << (pid_bits + 1)) - 1;
-	} else
-#endif
-	{
+		no_selective_tlbil = false;
+	} else {
 		first_context = 1;
 		last_context = 255;
+		no_selective_tlbil = false;
 	}
 
 #ifdef DEBUG_CLAMP_LAST_CONTEXT
@@ -428,12 +462,12 @@
 	/*
 	 * Allocate the maps used by context management
 	 */
-	context_map = alloc_bootmem(CTX_MAP_SIZE);
-	context_mm = alloc_bootmem(sizeof(void *) * (last_context + 1));
+	context_map = memblock_virt_alloc(CTX_MAP_SIZE, 0);
+	context_mm = memblock_virt_alloc(sizeof(void *) * (last_context + 1), 0);
 #ifndef CONFIG_SMP
-	stale_map[0] = alloc_bootmem(CTX_MAP_SIZE);
+	stale_map[0] = memblock_virt_alloc(CTX_MAP_SIZE, 0);
 #else
-	stale_map[boot_cpuid] = alloc_bootmem(CTX_MAP_SIZE);
+	stale_map[boot_cpuid] = memblock_virt_alloc(CTX_MAP_SIZE, 0);
 
 	register_cpu_notifier(&mmu_context_cpu_nb);
 #endif