diff options
Diffstat (limited to 'mm/vma.h')
| -rw-r--r-- | mm/vma.h | 47 |
1 files changed, 47 insertions, 0 deletions
@@ -222,6 +222,53 @@ static inline int vma_iter_store_gfp(struct vma_iterator *vmi, return 0; } + +/* + * Temporary helper functions for file systems which wrap an invocation of + * f_op->mmap() but which might have an underlying file system which implements + * f_op->mmap_prepare(). + */ + +static inline struct vm_area_desc *vma_to_desc(struct vm_area_struct *vma, + struct vm_area_desc *desc) +{ + desc->mm = vma->vm_mm; + desc->start = vma->vm_start; + desc->end = vma->vm_end; + + desc->pgoff = vma->vm_pgoff; + desc->file = vma->vm_file; + desc->vm_flags = vma->vm_flags; + desc->page_prot = vma->vm_page_prot; + + desc->vm_ops = NULL; + desc->private_data = NULL; + + return desc; +} + +static inline void set_vma_from_desc(struct vm_area_struct *vma, + struct vm_area_desc *desc) +{ + /* + * Since we're invoking .mmap_prepare() despite having a partially + * established VMA, we must take care to handle setting fields + * correctly. + */ + + /* Mutable fields. Populated with initial state. */ + vma->vm_pgoff = desc->pgoff; + if (vma->vm_file != desc->file) + vma_set_file(vma, desc->file); + if (vma->vm_flags != desc->vm_flags) + vm_flags_set(vma, desc->vm_flags); + vma->vm_page_prot = desc->page_prot; + + /* User-defined fields. */ + vma->vm_ops = desc->vm_ops; + vma->vm_private_data = desc->private_data; +} + int do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma, struct mm_struct *mm, unsigned long start, |