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-rw-r--r--include/asm-x86/xen/page.h168
1 files changed, 168 insertions, 0 deletions
diff --git a/include/asm-x86/xen/page.h b/include/asm-x86/xen/page.h
new file mode 100644
index 00000000000..01799305f02
--- /dev/null
+++ b/include/asm-x86/xen/page.h
@@ -0,0 +1,168 @@
+#ifndef __XEN_PAGE_H
+#define __XEN_PAGE_H
+
+#include <linux/pfn.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+
+#include <xen/features.h>
+
+/* Xen machine address */
+typedef struct xmaddr {
+ phys_addr_t maddr;
+} xmaddr_t;
+
+/* Xen pseudo-physical address */
+typedef struct xpaddr {
+ phys_addr_t paddr;
+} xpaddr_t;
+
+#define XMADDR(x) ((xmaddr_t) { .maddr = (x) })
+#define XPADDR(x) ((xpaddr_t) { .paddr = (x) })
+
+/**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
+#define INVALID_P2M_ENTRY (~0UL)
+#define FOREIGN_FRAME_BIT (1UL<<31)
+#define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT)
+
+extern unsigned long *phys_to_machine_mapping;
+
+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 0
+ if (unlikely((mfn >> machine_to_phys_order) != 0))
+ return max_mapnr;
+#endif
+
+ 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]);
+
+ return pfn;
+}
+
+static inline xmaddr_t phys_to_machine(xpaddr_t phys)
+{
+ unsigned offset = phys.paddr & ~PAGE_MASK;
+ return XMADDR(PFN_PHYS((u64)pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset);
+}
+
+static inline xpaddr_t machine_to_phys(xmaddr_t machine)
+{
+ unsigned offset = machine.maddr & ~PAGE_MASK;
+ return XPADDR(PFN_PHYS((u64)mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset);
+}
+
+/*
+ * 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)
+{
+ extern unsigned long max_mapnr;
+ unsigned long pfn = mfn_to_pfn(mfn);
+ if ((pfn < max_mapnr)
+ && !xen_feature(XENFEAT_auto_translated_physmap)
+ && (phys_to_machine_mapping[pfn] != mfn))
+ return max_mapnr; /* 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;
+}
+
+/* VIRT <-> MACHINE conversion */
+#define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v))))
+#define virt_to_mfn(v) (pfn_to_mfn(PFN_DOWN(__pa(v))))
+#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
+
+static inline unsigned long pte_mfn(pte_t pte)
+{
+ return (pte.pte & ~_PAGE_NX) >> PAGE_SHIFT;
+}
+
+static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot)
+{
+ pte_t pte;
+
+ pte.pte = ((phys_addr_t)page_nr << PAGE_SHIFT) |
+ (pgprot_val(pgprot) & __supported_pte_mask);
+
+ return pte;
+}
+
+static inline pteval_t pte_val_ma(pte_t pte)
+{
+ return pte.pte;
+}
+
+static inline pte_t __pte_ma(pteval_t x)
+{
+ return (pte_t) { .pte = x };
+}
+
+#ifdef CONFIG_X86_PAE
+#define pmd_val_ma(v) ((v).pmd)
+#define pud_val_ma(v) ((v).pgd.pgd)
+#define __pmd_ma(x) ((pmd_t) { (x) } )
+#else /* !X86_PAE */
+#define pmd_val_ma(v) ((v).pud.pgd.pgd)
+#endif /* CONFIG_X86_PAE */
+
+#define pgd_val_ma(x) ((x).pgd)
+
+
+xmaddr_t arbitrary_virt_to_machine(unsigned long address);
+void make_lowmem_page_readonly(void *vaddr);
+void make_lowmem_page_readwrite(void *vaddr);
+
+#endif /* __XEN_PAGE_H */