This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / include / asm-x86_64 / mach-xen / asm / maddr.h

diff --git a/include/asm-x86_64/mach-xen/asm/maddr.h b/include/asm-x86_64/mach-xen/asm/maddr.h
new file mode 100644 (file)
index 0000000..0104de8
--- /dev/null
+++ b/include/asm-x86_64/mach-xen/asm/maddr.h
@@ -0,0 +1,139 @@
+#ifndef _X86_64_MADDR_H
+#define _X86_64_MADDR_H
+
+#include <xen/features.h>
+#include <xen/interface/xen.h>
+
+/**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
+#define INVALID_P2M_ENTRY      (~0UL)
+#define FOREIGN_FRAME_BIT      (1UL<<63)
+#define FOREIGN_FRAME(m)       ((m) | FOREIGN_FRAME_BIT)
+
+#ifdef CONFIG_XEN
+
+extern unsigned long *phys_to_machine_mapping;
+
+#undef machine_to_phys_mapping
+extern unsigned long *machine_to_phys_mapping;
+extern unsigned int   machine_to_phys_order;
+
+static inline unsigned long pfn_to_mfn(unsigned long pfn)
+{
+       if (xen_feature(XENFEAT_auto_translated_physmap))
+               return pfn;
+       return phys_to_machine_mapping[(unsigned int)(pfn)] &
+               ~FOREIGN_FRAME_BIT;
+}
+
+static inline int phys_to_machine_mapping_valid(unsigned long pfn)
+{
+       if (xen_feature(XENFEAT_auto_translated_physmap))
+               return 1;
+       return (phys_to_machine_mapping[pfn] != INVALID_P2M_ENTRY);
+}
+
+static inline unsigned long mfn_to_pfn(unsigned long mfn)
+{
+       unsigned long pfn;
+
+       if (xen_feature(XENFEAT_auto_translated_physmap))
+               return mfn;
+
+       if (unlikely((mfn >> machine_to_phys_order) != 0))
+               return end_pfn;
+
+       /* The array access can fail (e.g., device space beyond end of RAM). */
+       asm (
+               "1:     movq %1,%0\n"
+               "2:\n"
+               ".section .fixup,\"ax\"\n"
+               "3:     movq %2,%0\n"
+               "       jmp  2b\n"
+               ".previous\n"
+               ".section __ex_table,\"a\"\n"
+               "       .align 8\n"
+               "       .quad 1b,3b\n"
+               ".previous"
+               : "=r" (pfn)
+               : "m" (machine_to_phys_mapping[mfn]), "m" (end_pfn) );
+
+       return pfn;
+}
+
+/*
+ * We detect special mappings in one of two ways:
+ *  1. If the MFN is an I/O page then Xen will set the m2p entry
+ *     to be outside our maximum possible pseudophys range.
+ *  2. If the MFN belongs to a different domain then we will certainly
+ *     not have MFN in our p2m table. Conversely, if the page is ours,
+ *     then we'll have p2m(m2p(MFN))==MFN.
+ * If we detect a special mapping then it doesn't have a 'struct page'.
+ * We force !pfn_valid() by returning an out-of-range pointer.
+ *
+ * NB. These checks require that, for any MFN that is not in our reservation,
+ * there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if
+ * we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN.
+ * Yikes! Various places must poke in INVALID_P2M_ENTRY for safety.
+ *
+ * NB2. When deliberately mapping foreign pages into the p2m table, you *must*
+ *      use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we
+ *      require. In all the cases we care about, the FOREIGN_FRAME bit is
+ *      masked (e.g., pfn_to_mfn()) so behaviour there is correct.
+ */
+static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
+{
+       unsigned long pfn = mfn_to_pfn(mfn);
+       if ((pfn < end_pfn)
+           && !xen_feature(XENFEAT_auto_translated_physmap)
+           && (phys_to_machine_mapping[pfn] != mfn))
+               return end_pfn; /* force !pfn_valid() */
+       return pfn;
+}
+
+static inline void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
+{
+       if (xen_feature(XENFEAT_auto_translated_physmap)) {
+               BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
+               return;
+       }
+       phys_to_machine_mapping[pfn] = mfn;
+}
+
+#else /* !CONFIG_XEN */
+
+#define pfn_to_mfn(pfn) (pfn)
+#define mfn_to_pfn(mfn) (mfn)
+#define mfn_to_local_pfn(mfn) (mfn)
+#define set_phys_to_machine(pfn, mfn) BUG_ON((pfn) != (mfn))
+#define phys_to_machine_mapping_valid(pfn) (1)
+
+#endif /* !CONFIG_XEN */
+
+/* Definitions for machine and pseudophysical addresses. */
+typedef unsigned long paddr_t;
+typedef unsigned long maddr_t;
+
+static inline maddr_t phys_to_machine(paddr_t phys)
+{
+       maddr_t machine = pfn_to_mfn(phys >> PAGE_SHIFT);
+       machine = (machine << PAGE_SHIFT) | (phys & ~PAGE_MASK);
+       return machine;
+}
+
+static inline paddr_t machine_to_phys(maddr_t machine)
+{
+       paddr_t phys = mfn_to_pfn(machine >> PAGE_SHIFT);
+       phys = (phys << PAGE_SHIFT) | (machine & ~PAGE_MASK);
+       return phys;
+}
+
+/* VIRT <-> MACHINE conversion */
+#define virt_to_machine(v)     (phys_to_machine(__pa(v)))
+#define virt_to_mfn(v)         (pfn_to_mfn(__pa(v) >> PAGE_SHIFT))
+#define mfn_to_virt(m)         (__va(mfn_to_pfn(m) << PAGE_SHIFT))
+
+#define __pte_ma(x)     ((pte_t) { (x) } )
+#define pfn_pte_ma(pfn, prot)  __pte_ma((((pfn) << PAGE_SHIFT) | pgprot_val(prot)) & __supported_pte_mask)
+
+#endif /* _X86_64_MADDR_H */
+