1 files changed, 73 insertions, 10 deletions

diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h
index dd8c1414b3d..c949923a566 100644
--- a/arch/x86/include/asm/xen/page.h
+++ b/arch/x86/include/asm/xen/page.h
@@ -5,12 +5,14 @@
 #include <linux/types.h>
 #include <linux/spinlock.h>
 #include <linux/pfn.h>
+#include <linux/mm.h>
 
 #include <asm/uaccess.h>
 #include <asm/page.h>
 #include <asm/pgtable.h>
 
 #include <xen/interface/xen.h>
+#include <xen/grant_table.h>
 #include <xen/features.h>
 
 /* Xen machine address */
@@ -28,16 +30,38 @@ typedef struct xpaddr {
 
 /**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
 #define INVALID_P2M_ENTRY	(~0UL)
-#define FOREIGN_FRAME_BIT	(1UL<<31)
+#define FOREIGN_FRAME_BIT	(1UL<<(BITS_PER_LONG-1))
+#define IDENTITY_FRAME_BIT	(1UL<<(BITS_PER_LONG-2))
 #define FOREIGN_FRAME(m)	((m) | FOREIGN_FRAME_BIT)
+#define IDENTITY_FRAME(m)	((m) | IDENTITY_FRAME_BIT)
 
 /* Maximum amount of memory we can handle in a domain in pages */
 #define MAX_DOMAIN_PAGES						\
     ((unsigned long)((u64)CONFIG_XEN_MAX_DOMAIN_MEMORY * 1024 * 1024 * 1024 / PAGE_SIZE))
 
+extern unsigned long *machine_to_phys_mapping;
+extern unsigned long  machine_to_phys_nr;
 
 extern unsigned long get_phys_to_machine(unsigned long pfn);
 extern bool set_phys_to_machine(unsigned long pfn, unsigned long mfn);
+extern bool __init early_set_phys_to_machine(unsigned long pfn, unsigned long mfn);
+extern bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn);
+extern unsigned long set_phys_range_identity(unsigned long pfn_s,
+					     unsigned long pfn_e);
+
+extern int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
+				   struct gnttab_map_grant_ref *kmap_ops,
+				   struct page **pages, unsigned int count);
+extern int m2p_add_override(unsigned long mfn, struct page *page,
+			    struct gnttab_map_grant_ref *kmap_op);
+extern int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
+				     struct gnttab_map_grant_ref *kmap_ops,
+				     struct page **pages, unsigned int count);
+extern int m2p_remove_override(struct page *page,
+			       struct gnttab_map_grant_ref *kmap_op,
+			       unsigned long mfn);
+extern struct page *m2p_find_override(unsigned long mfn);
+extern unsigned long m2p_find_override_pfn(unsigned long mfn, unsigned long pfn);
 
 static inline unsigned long pfn_to_mfn(unsigned long pfn)
 {
@@ -49,7 +73,7 @@ static inline unsigned long pfn_to_mfn(unsigned long pfn)
 	mfn = get_phys_to_machine(pfn);
 
 	if (mfn != INVALID_P2M_ENTRY)
-		mfn &= ~FOREIGN_FRAME_BIT;
+		mfn &= ~(FOREIGN_FRAME_BIT | IDENTITY_FRAME_BIT);
 
 	return mfn;
 }
@@ -62,25 +86,56 @@ static inline int phys_to_machine_mapping_valid(unsigned long pfn)
 	return get_phys_to_machine(pfn) != INVALID_P2M_ENTRY;
 }
 
-static inline unsigned long mfn_to_pfn(unsigned long mfn)
+static inline unsigned long mfn_to_pfn_no_overrides(unsigned long mfn)
 {
 	unsigned long pfn;
+	int ret;
 
 	if (xen_feature(XENFEAT_auto_translated_physmap))
 		return mfn;
 
-#if 0
-	if (unlikely((mfn >> machine_to_phys_order) != 0))
-		return max_mapnr;
-#endif
+	if (unlikely(mfn >= machine_to_phys_nr))
+		return ~0;
 
-	pfn = 0;
 	/*
 	 * The array access can fail (e.g., device space beyond end of RAM).
 	 * In such cases it doesn't matter what we return (we return garbage),
 	 * but we must handle the fault without crashing!
 	 */
-	__get_user(pfn, &machine_to_phys_mapping[mfn]);
+	ret = __get_user(pfn, &machine_to_phys_mapping[mfn]);
+	if (ret < 0)
+		return ~0;
+
+	return pfn;
+}
+
+static inline unsigned long mfn_to_pfn(unsigned long mfn)
+{
+	unsigned long pfn;
+
+	if (xen_feature(XENFEAT_auto_translated_physmap))
+		return mfn;
+
+	pfn = mfn_to_pfn_no_overrides(mfn);
+	if (get_phys_to_machine(pfn) != mfn) {
+		/*
+		 * If this appears to be a foreign mfn (because the pfn
+		 * doesn't map back to the mfn), then check the local override
+		 * table to see if there's a better pfn to use.
+		 *
+		 * m2p_find_override_pfn returns ~0 if it doesn't find anything.
+		 */
+		pfn = m2p_find_override_pfn(mfn, ~0);
+	}
+
+	/*
+	 * pfn is ~0 if there are no entries in the m2p for mfn or if the
+	 * entry doesn't map back to the mfn and m2p_override doesn't have a
+	 * valid entry for it.
+	 */
+	if (pfn == ~0 &&
+			get_phys_to_machine(mfn) == IDENTITY_FRAME(mfn))
+		pfn = mfn;
 
 	return pfn;
 }
@@ -119,7 +174,12 @@ static inline xpaddr_t machine_to_phys(xmaddr_t machine)
  */
 static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
 {
-	unsigned long pfn = mfn_to_pfn(mfn);
+	unsigned long pfn;
+
+	if (xen_feature(XENFEAT_auto_translated_physmap))
+		return mfn;
+
+	pfn = mfn_to_pfn(mfn);
 	if (get_phys_to_machine(pfn) != mfn)
 		return -1; /* force !pfn_valid() */
 	return pfn;
@@ -173,4 +233,7 @@ unsigned long arbitrary_virt_to_mfn(void *vaddr);
 void make_lowmem_page_readonly(void *vaddr);
 void make_lowmem_page_readwrite(void *vaddr);
 
+#define xen_remap(cookie, size) ioremap((cookie), (size));
+#define xen_unmap(cookie) iounmap((cookie))
+
 #endif /* _ASM_X86_XEN_PAGE_H */