diff options
Diffstat (limited to 'drivers/char/mem.c')
| -rw-r--r-- | drivers/char/mem.c | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 56b2fb4fbc9..e83623ead44 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -300,6 +300,35 @@ static inline int private_mapping_ok(struct vm_area_struct *vma) } #endif +void __attribute__((weak)) +map_devmem(unsigned long pfn, unsigned long len, pgprot_t prot) +{ + /* nothing. architectures can override. */ +} + +void __attribute__((weak)) +unmap_devmem(unsigned long pfn, unsigned long len, pgprot_t prot) +{ + /* nothing. architectures can override. */ +} + +static void mmap_mem_open(struct vm_area_struct *vma) +{ + map_devmem(vma->vm_pgoff, vma->vm_end - vma->vm_start, + vma->vm_page_prot); +} + +static void mmap_mem_close(struct vm_area_struct *vma) +{ + unmap_devmem(vma->vm_pgoff, vma->vm_end - vma->vm_start, + vma->vm_page_prot); +} + +static struct vm_operations_struct mmap_mem_ops = { + .open = mmap_mem_open, + .close = mmap_mem_close +}; + static int mmap_mem(struct file * file, struct vm_area_struct * vma) { size_t size = vma->vm_end - vma->vm_start; @@ -321,13 +350,17 @@ static int mmap_mem(struct file * file, struct vm_area_struct * vma) size, vma->vm_page_prot); + vma->vm_ops = &mmap_mem_ops; + /* Remap-pfn-range will mark the range VM_IO and VM_RESERVED */ if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, size, - vma->vm_page_prot)) + vma->vm_page_prot)) { + unmap_devmem(vma->vm_pgoff, size, vma->vm_page_prot); return -EAGAIN; + } return 0; } |