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-rw-r--r--arch/alpha/mm/remap.c90
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 00000000000..19817ad3d89
--- /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;
+}
+