1 files changed, 155 insertions, 0 deletions
diff --git a/arch/sparc/include/asm/mmu_context_64.h b/arch/sparc/include/asm/mmu_context_64.h
new file mode 100644
index 000000000000..5693ab482606
--- /dev/null
+++ b/arch/sparc/include/asm/mmu_context_64.h
@@ -0,0 +1,155 @@
+#ifndef __SPARC64_MMU_CONTEXT_H
+#define __SPARC64_MMU_CONTEXT_H
+
+/* Derived heavily from Linus's Alpha/AXP ASN code... */
+
+#ifndef __ASSEMBLY__
+
+#include <linux/spinlock.h>
+#include <asm/system.h>
+#include <asm/spitfire.h>
+#include <asm-generic/mm_hooks.h>
+
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+extern spinlock_t ctx_alloc_lock;
+extern unsigned long tlb_context_cache;
+extern unsigned long mmu_context_bmap[];
+
+extern void get_new_mmu_context(struct mm_struct *mm);
+#ifdef CONFIG_SMP
+extern void smp_new_mmu_context_version(void);
+#else
+#define smp_new_mmu_context_version() do { } while (0)
+#endif
+
+extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
+extern void destroy_context(struct mm_struct *mm);
+
+extern void __tsb_context_switch(unsigned long pgd_pa,
+				 struct tsb_config *tsb_base,
+				 struct tsb_config *tsb_huge,
+				 unsigned long tsb_descr_pa);
+
+static inline void tsb_context_switch(struct mm_struct *mm)
+{
+	__tsb_context_switch(__pa(mm->pgd),
+			     &mm->context.tsb_block[0],
+#ifdef CONFIG_HUGETLB_PAGE
+			     (mm->context.tsb_block[1].tsb ?
+			      &mm->context.tsb_block[1] :
+			      NULL)
+#else
+			     NULL
+#endif
+			     , __pa(&mm->context.tsb_descr[0]));
+}
+
+extern void tsb_grow(struct mm_struct *mm, unsigned long tsb_index, unsigned long mm_rss);
+#ifdef CONFIG_SMP
+extern void smp_tsb_sync(struct mm_struct *mm);
+#else
+#define smp_tsb_sync(__mm) do { } while (0)
+#endif
+
+/* Set MMU context in the actual hardware. */
+#define load_secondary_context(__mm) \
+	__asm__ __volatile__( \
+	"\n661:	stxa		%0, [%1] %2\n" \
+	"	.section	.sun4v_1insn_patch, \"ax\"\n" \
+	"	.word		661b\n" \
+	"	stxa		%0, [%1] %3\n" \
+	"	.previous\n" \
+	"	flush		%%g6\n" \
+	: /* No outputs */ \
+	: "r" (CTX_HWBITS((__mm)->context)), \
+	  "r" (SECONDARY_CONTEXT), "i" (ASI_DMMU), "i" (ASI_MMU))
+
+extern void __flush_tlb_mm(unsigned long, unsigned long);
+
+/* Switch the current MM context.  Interrupts are disabled.  */
+static inline void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm, struct task_struct *tsk)
+{
+	unsigned long ctx_valid, flags;
+	int cpu;
+
+	if (unlikely(mm == &init_mm))
+		return;
+
+	spin_lock_irqsave(&mm->context.lock, flags);
+	ctx_valid = CTX_VALID(mm->context);
+	if (!ctx_valid)
+		get_new_mmu_context(mm);
+
+	/* We have to be extremely careful here or else we will miss
+	 * a TSB grow if we switch back and forth between a kernel
+	 * thread and an address space which has it's TSB size increased
+	 * on another processor.
+	 *
+	 * It is possible to play some games in order to optimize the
+	 * switch, but the safest thing to do is to unconditionally
+	 * perform the secondary context load and the TSB context switch.
+	 *
+	 * For reference the bad case is, for address space "A":
+	 *
+	 *		CPU 0			CPU 1
+	 *	run address space A
+	 *	set cpu0's bits in cpu_vm_mask
+	 *	switch to kernel thread, borrow
+	 *	address space A via entry_lazy_tlb
+	 *					run address space A
+	 *					set cpu1's bit in cpu_vm_mask
+	 *					flush_tlb_pending()
+	 *					reset cpu_vm_mask to just cpu1
+	 *					TSB grow
+	 *	run address space A
+	 *	context was valid, so skip
+	 *	TSB context switch
+	 *
+	 * At that point cpu0 continues to use a stale TSB, the one from
+	 * before the TSB grow performed on cpu1.  cpu1 did not cross-call
+	 * cpu0 to update it's TSB because at that point the cpu_vm_mask
+	 * only had cpu1 set in it.
+	 */
+	load_secondary_context(mm);
+	tsb_context_switch(mm);
+
+	/* Any time a processor runs a context on an address space
+	 * for the first time, we must flush that context out of the
+	 * local TLB.
+	 */
+	cpu = smp_processor_id();
+	if (!ctx_valid || !cpu_isset(cpu, mm->cpu_vm_mask)) {
+		cpu_set(cpu, mm->cpu_vm_mask);
+		__flush_tlb_mm(CTX_HWBITS(mm->context),
+			       SECONDARY_CONTEXT);
+	}
+	spin_unlock_irqrestore(&mm->context.lock, flags);
+}
+
+#define deactivate_mm(tsk,mm)	do { } while (0)
+
+/* Activate a new MM instance for the current task. */
+static inline void activate_mm(struct mm_struct *active_mm, struct mm_struct *mm)
+{
+	unsigned long flags;
+	int cpu;
+
+	spin_lock_irqsave(&mm->context.lock, flags);
+	if (!CTX_VALID(mm->context))
+		get_new_mmu_context(mm);
+	cpu = smp_processor_id();
+	if (!cpu_isset(cpu, mm->cpu_vm_mask))
+		cpu_set(cpu, mm->cpu_vm_mask);
+
+	load_secondary_context(mm);
+	__flush_tlb_mm(CTX_HWBITS(mm->context), SECONDARY_CONTEXT);
+	tsb_context_switch(mm);
+	spin_unlock_irqrestore(&mm->context.lock, flags);
+}
+
+#endif /* !(__ASSEMBLY__) */
+
+#endif /* !(__SPARC64_MMU_CONTEXT_H) */