1 files changed, 126 insertions, 0 deletions

diff --git a/linux-2.6-xen-sparse/include/asm-xen/asm-x86_64/mmu_context.h b/linux-2.6-xen-sparse/include/asm-xen/asm-x86_64/mmu_context.h
new file mode 100644
index 0000000000..592bef5b7d
--- /dev/null
+++ b/linux-2.6-xen-sparse/include/asm-xen/asm-x86_64/mmu_context.h
@@ -0,0 +1,126 @@
+#ifndef __X86_64_MMU_CONTEXT_H
+#define __X86_64_MMU_CONTEXT_H
+
+#include <linux/config.h>
+#include <asm/desc.h>
+#include <asm/atomic.h>
+#include <asm/pgalloc.h>
+#include <asm/page.h>
+#include <asm/pda.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+
+/*
+ * possibly do the LDT unload here?
+ */
+int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
+void destroy_context(struct mm_struct *mm);
+
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+#if 0 /*  XEN: no lazy tlb */
+	if (read_pda(mmu_state) == TLBSTATE_OK) 
+		write_pda(mmu_state, TLBSTATE_LAZY);
+#endif
+}
+
+#define prepare_arch_switch(rq,next)	__prepare_arch_switch()
+#define finish_arch_switch(rq, next)	spin_unlock_irq(&(rq)->lock)
+#define task_running(rq, p)		((rq)->curr == (p))
+
+static inline void __prepare_arch_switch(void)
+{
+	/*
+	 * Save away %es, %ds, %fs and %gs. Must happen before reload
+	 * of cr3/ldt (i.e., not in __switch_to).
+	 */
+	__asm__ __volatile__ (
+		"movl %%es,%0 ; movl %%ds,%1 ; movl %%fs,%2 ; movl %%gs,%3"
+		: "=m" (current->thread.es),
+		  "=m" (current->thread.ds),
+		  "=m" (current->thread.fsindex),
+		  "=m" (current->thread.gsindex) );
+
+	if (current->thread.ds)
+		__asm__ __volatile__ ( "movl %0,%%ds" : : "r" (0) );
+
+	if (current->thread.es)
+		__asm__ __volatile__ ( "movl %0,%%es" : : "r" (0) );
+
+	if (current->thread.fsindex) {
+		__asm__ __volatile__ ( "movl %0,%%fs" : : "r" (0) );
+		current->thread.fs = 0;
+	}
+
+	if (current->thread.gsindex) {
+		load_gs_index(0);
+		current->thread.gs = 0;
+	}
+}
+
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 
+			     struct task_struct *tsk)
+{
+	unsigned cpu = smp_processor_id();
+	struct mmuext_op _op[3], *op = _op;
+
+	if (likely(prev != next)) {
+		/* stop flush ipis for the previous mm */
+		clear_bit(cpu, &prev->cpu_vm_mask);
+#if 0  /* XEN: no lazy tlb */
+		write_pda(mmu_state, TLBSTATE_OK);
+		write_pda(active_mm, next);
+#endif
+		set_bit(cpu, &next->cpu_vm_mask);
+
+		/* load_cr3(next->pgd) */
+		per_cpu(cur_pgd, smp_processor_id()) = next->pgd;
+		op->cmd = MMUEXT_NEW_BASEPTR;
+		op->mfn = pfn_to_mfn(__pa(next->pgd) >> PAGE_SHIFT);
+		op++;
+
+		/* xen_new_user_pt(__pa(__user_pgd(next->pgd))) */
+		op->cmd = MMUEXT_NEW_USER_BASEPTR;
+		op->mfn = pfn_to_mfn(__pa(__user_pgd(next->pgd)) >> PAGE_SHIFT);
+		op++;
+		
+		if (unlikely(next->context.ldt != prev->context.ldt)) {
+			/* load_LDT_nolock(&next->context, cpu) */
+			op->cmd = MMUEXT_SET_LDT;
+			op->linear_addr = (unsigned long)next->context.ldt;
+			op->nr_ents     = next->context.size;
+			op++;
+		}
+
+		BUG_ON(HYPERVISOR_mmuext_op(_op, op-_op, NULL, DOMID_SELF));
+	}
+
+#if 0 /* XEN: no lazy tlb */
+	else {
+		write_pda(mmu_state, TLBSTATE_OK);
+		if (read_pda(active_mm) != next)
+			out_of_line_bug();
+		if(!test_and_set_bit(cpu, &next->cpu_vm_mask)) {
+			/* We were in lazy tlb mode and leave_mm disabled 
+			 * tlb flush IPI delivery. We must reload CR3
+			 * to make sure to use no freed page tables.
+			 */
+                        load_cr3(next->pgd);
+                        xen_new_user_pt(__pa(__user_pgd(next->pgd)));		
+			load_LDT_nolock(&next->context, cpu);
+		}
+	}
+#endif
+}
+
+#define deactivate_mm(tsk,mm)	do { \
+	load_gs_index(0); \
+	asm volatile("movl %0,%%fs"::"r"(0));  \
+} while(0)
+
+#define activate_mm(prev, next) do {		\
+	switch_mm((prev),(next),NULL);		\
+} while (0)
+
+#endif