1 files changed, 90 insertions, 0 deletions

diff --git a/arch/alpha/mm/remap.c b/arch/alpha/mm/remap.c
new file mode 100644
index 000000000000..19817ad3d89b
--- /dev/null
+++ b/arch/alpha/mm/remap.c
@@ -0,0 +1,90 @@
+#include <linux/vmalloc.h>
+#include <asm/pgalloc.h>
+#include <asm/cacheflush.h>
+
+/* called with the page_table_lock held */
+static inline void 
+remap_area_pte(pte_t * pte, unsigned long address, unsigned long size, 
+               unsigned long phys_addr, unsigned long flags)
+{
+        unsigned long end;
+        unsigned long pfn;
+
+        address &= ~PMD_MASK;
+        end = address + size;
+        if (end > PMD_SIZE)
+                end = PMD_SIZE;
+        if (address >= end)
+                BUG();
+        pfn = phys_addr >> PAGE_SHIFT;
+        do {
+                if (!pte_none(*pte)) {
+                        printk("remap_area_pte: page already exists\n");
+                        BUG();
+                }
+                set_pte(pte, pfn_pte(pfn, 
+                                     __pgprot(_PAGE_VALID | _PAGE_ASM | 
+                                              _PAGE_KRE | _PAGE_KWE | flags)));
+                address += PAGE_SIZE;
+                pfn++;
+                pte++;
+        } while (address && (address < end));
+}
+
+/* called with the page_table_lock held */
+static inline int 
+remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size, 
+               unsigned long phys_addr, unsigned long flags)
+{
+        unsigned long end;
+
+        address &= ~PGDIR_MASK;
+        end = address + size;
+        if (end > PGDIR_SIZE)
+                end = PGDIR_SIZE;
+        phys_addr -= address;
+        if (address >= end)
+                BUG();
+        do {
+                pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+                if (!pte)
+                        return -ENOMEM;
+                remap_area_pte(pte, address, end - address, 
+                                     address + phys_addr, flags);
+                address = (address + PMD_SIZE) & PMD_MASK;
+                pmd++;
+        } while (address && (address < end));
+        return 0;
+}
+
+int
+__alpha_remap_area_pages(unsigned long address, unsigned long phys_addr,
+                         unsigned long size, unsigned long flags)
+{
+        pgd_t * dir;
+        int error = 0;
+        unsigned long end = address + size;
+
+        phys_addr -= address;
+        dir = pgd_offset(&init_mm, address);
+        flush_cache_all();
+        if (address >= end)
+                BUG();
+        spin_lock(&init_mm.page_table_lock);
+        do {
+                pmd_t *pmd;
+                pmd = pmd_alloc(&init_mm, dir, address);
+                error = -ENOMEM;
+                if (!pmd)
+                        break;
+                if (remap_area_pmd(pmd, address, end - address,
+                                   phys_addr + address, flags))
+                        break;
+                error = 0;
+                address = (address + PGDIR_SIZE) & PGDIR_MASK;
+                dir++;
+        } while (address && (address < end));
+        spin_unlock(&init_mm.page_table_lock);
+        return error;
+}
+