x86/paravirt/xen: add set_fixmap pv_mmu_ops

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/paravirt.c

@@ -416,6 +416,8 @@ struct pv_mmu_ops pv_mmu_ops = {
 		.enter = paravirt_nop,
 		.leave = paravirt_nop,
 	},
+
+	.set_fixmap = native_set_fixmap,
 };
 
 EXPORT_SYMBOL_GPL(pv_time_ops);

arch/x86/mm/pgtable.c

@@ -277,7 +277,7 @@ int ptep_clear_flush_young(struct vm_area_struct *vma,
 
 int fixmaps_set;
 
-void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags)
+void __native_set_fixmap(enum fixed_addresses idx, pte_t pte)
 {
 	unsigned long address = __fix_to_virt(idx);
 
@@ -285,6 +285,11 @@ void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags)
 		BUG();
 		return;
 	}
-	set_pte_vaddr(address, pfn_pte(phys >> PAGE_SHIFT, flags));
+	set_pte_vaddr(address, pte);
 	fixmaps_set++;
 }
+
+void native_set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t flags)
+{
+	__native_set_fixmap(idx, pfn_pte(phys >> PAGE_SHIFT, flags));
+}

arch/x86/xen/enlighten.c

@@ -960,6 +960,33 @@ static unsigned xen_patch(u8 type, u16 clobbers, void *insnbuf,
 	return ret;
 }
 
+static void xen_set_fixmap(unsigned idx, unsigned long phys, pgprot_t prot)
+{
+	pte_t pte;
+
+	phys >>= PAGE_SHIFT;
+
+	switch (idx) {
+	case FIX_BTMAP_END ... FIX_BTMAP_BEGIN:
+#ifdef CONFIG_X86_F00F_BUG
+	case FIX_F00F_IDT:
+#endif
+	case FIX_WP_TEST:
+	case FIX_VDSO:
+#ifdef CONFIG_X86_LOCAL_APIC
+	case FIX_APIC_BASE:	/* maps dummy local APIC */
+#endif
+		pte = pfn_pte(phys, prot);
+		break;
+
+	default:
+		pte = mfn_pte(phys, prot);
+		break;
+	}
+
+	__native_set_fixmap(idx, pte);
+}
+
 static const struct pv_info xen_info __initdata = {
 	.paravirt_enabled = 1,
 	.shared_kernel_pmd = 0,
@@ -1112,6 +1139,8 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = {
 		.enter = paravirt_enter_lazy_mmu,
 		.leave = xen_leave_lazy,
 	},
+
+	.set_fixmap = xen_set_fixmap,
 };
 
 #ifdef CONFIG_SMP

include/asm-x86/fixmap.h

@@ -9,8 +9,18 @@
 
 extern int fixmaps_set;
 
-extern void __set_fixmap(enum fixed_addresses idx,
+void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
+void native_set_fixmap(enum fixed_addresses idx,
 		       unsigned long phys, pgprot_t flags);
+
+#ifndef CONFIG_PARAVIRT
+static inline void __set_fixmap(enum fixed_addresses idx,
+				unsigned long phys, pgprot_t flags)
+{
+	native_set_fixmap(idx, phys, flags);
+}
+#endif
+
 #define set_fixmap(idx, phys)				\
 	__set_fixmap(idx, phys, PAGE_KERNEL)
 

include/asm-x86/paravirt.h

@@ -273,6 +273,13 @@ struct pv_mmu_ops {
 #endif
 
 	struct pv_lazy_ops lazy_mode;
+
+	/* dom0 ops */
+
+	/* Sometimes the physical address is a pfn, and sometimes its
+	   an mfn.  We can tell which is which from the index. */
+	void (*set_fixmap)(unsigned /* enum fixed_addresses */ idx,
+			   unsigned long phys, pgprot_t flags);
 };
 
 /* This contains all the paravirt structures: we get a convenient
@@ -1252,6 +1259,12 @@ static inline void arch_flush_lazy_mmu_mode(void)
 	}
 }
 
+static inline void __set_fixmap(unsigned /* enum fixed_addresses */ idx,
+				unsigned long phys, pgprot_t flags)
+{
+	pv_mmu_ops.set_fixmap(idx, phys, flags);
+}
+
 void _paravirt_nop(void);
 #define paravirt_nop	((void *)_paravirt_nop)