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-rw-r--r--arch/sparc/include/asm/mmu_context_64.h155
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) */
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