root/arch/csky/mm/ioremap.c

DEFINITIONS

1. __ioremap_caller
2. __ioremap
3. ioremap_cache
4. iounmap
5. phys_mem_access_prot

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
   3 
   4 #include <linux/export.h>
   5 #include <linux/mm.h>
   6 #include <linux/vmalloc.h>
   7 #include <linux/io.h>
   8 
   9 #include <asm/pgtable.h>
  10 
  11 static void __iomem *__ioremap_caller(phys_addr_t addr, size_t size,
  12                                       pgprot_t prot, void *caller)
  13 {
  14         phys_addr_t last_addr;
  15         unsigned long offset, vaddr;
  16         struct vm_struct *area;
  17 
  18         last_addr = addr + size - 1;
  19         if (!size || last_addr < addr)
  20                 return NULL;
  21 
  22         offset = addr & (~PAGE_MASK);
  23         addr &= PAGE_MASK;
  24         size = PAGE_ALIGN(size + offset);
  25 
  26         area = get_vm_area_caller(size, VM_IOREMAP, caller);
  27         if (!area)
  28                 return NULL;
  29 
  30         vaddr = (unsigned long)area->addr;
  31 
  32         if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) {
  33                 free_vm_area(area);
  34                 return NULL;
  35         }
  36 
  37         return (void __iomem *)(vaddr + offset);
  38 }
  39 
  40 void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot)
  41 {
  42         return __ioremap_caller(phys_addr, size, prot,
  43                                 __builtin_return_address(0));
  44 }
  45 EXPORT_SYMBOL(__ioremap);
  46 
  47 void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size)
  48 {
  49         return __ioremap_caller(phys_addr, size, PAGE_KERNEL,
  50                                 __builtin_return_address(0));
  51 }
  52 EXPORT_SYMBOL(ioremap_cache);
  53 
  54 void iounmap(void __iomem *addr)
  55 {
  56         vunmap((void *)((unsigned long)addr & PAGE_MASK));
  57 }
  58 EXPORT_SYMBOL(iounmap);
  59 
  60 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
  61                               unsigned long size, pgprot_t vma_prot)
  62 {
  63         if (!pfn_valid(pfn)) {
  64                 return pgprot_noncached(vma_prot);
  65         } else if (file->f_flags & O_SYNC) {
  66                 return pgprot_writecombine(vma_prot);
  67         }
  68 
  69         return vma_prot;
  70 }
  71 EXPORT_SYMBOL(phys_mem_access_prot);