| /* |
| * 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 <linux/sched.h> |
| #include <linux/io.h> |
| #include <linux/module.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; |
| } |
| EXPORT_SYMBOL(ioremap_page_range); |
| |