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

[linux-2.6.git] / lib / ioremap.c

diff --git a/lib/ioremap.c b/lib/ioremap.c
new file mode 100644 (file)
index 0000000..a9e4415
--- /dev/null
+++ b/lib/ioremap.c
@@ -0,0 +1,91 @@
+/*
+ * Re-map IO memory to kernel address space so that we can access it.
+ * This is needed for high PCI addresses that aren't mapped in the
+ * 640k-1MB IO memory area on PC's
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ */
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+
+#include <asm/cacheflush.h>
+#include <asm/pgtable.h>
+
+static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
+               unsigned long end, unsigned long phys_addr, pgprot_t prot)
+{
+       pte_t *pte;
+       unsigned long pfn;
+
+       pfn = phys_addr >> PAGE_SHIFT;
+       pte = pte_alloc_kernel(pmd, addr);
+       if (!pte)
+               return -ENOMEM;
+       do {
+               BUG_ON(!pte_none(*pte));
+               set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
+               pfn++;
+       } while (pte++, addr += PAGE_SIZE, addr != end);
+       return 0;
+}
+
+static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
+               unsigned long end, unsigned long phys_addr, pgprot_t prot)
+{
+       pmd_t *pmd;
+       unsigned long next;
+
+       phys_addr -= addr;
+       pmd = pmd_alloc(&init_mm, pud, addr);
+       if (!pmd)
+               return -ENOMEM;
+       do {
+               next = pmd_addr_end(addr, end);
+               if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
+                       return -ENOMEM;
+       } while (pmd++, addr = next, addr != end);
+       return 0;
+}
+
+static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
+               unsigned long end, unsigned long phys_addr, pgprot_t prot)
+{
+       pud_t *pud;
+       unsigned long next;
+
+       phys_addr -= addr;
+       pud = pud_alloc(&init_mm, pgd, addr);
+       if (!pud)
+               return -ENOMEM;
+       do {
+               next = pud_addr_end(addr, end);
+               if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
+                       return -ENOMEM;
+       } while (pud++, addr = next, addr != end);
+       return 0;
+}
+
+int ioremap_page_range(unsigned long addr,
+                      unsigned long end, unsigned long phys_addr, pgprot_t prot)
+{
+       pgd_t *pgd;
+       unsigned long start;
+       unsigned long next;
+       int err;
+
+       BUG_ON(addr >= end);
+
+       start = addr;
+       phys_addr -= addr;
+       pgd = pgd_offset_k(addr);
+       do {
+               next = pgd_addr_end(addr, end);
+               err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot);
+               if (err)
+                       break;
+       } while (pgd++, addr = next, addr != end);
+
+       flush_cache_vmap(start, end);
+
+       return err;
+}