C++ (Cpp) msync_interval 예제들

예제 #1

파일: msync.c 프로젝트: BackupTheBerlios/tuxap

asmlinkage long sys_msync(unsigned long start, size_t len, int flags)
{
	unsigned long end;
	struct vm_area_struct * vma;
	int unmapped_error, error = -EINVAL;

	down_read(&current->mm->mmap_sem);
	if (flags & ~(MS_ASYNC | MS_INVALIDATE | MS_SYNC))
		goto out;
	if (start & ~PAGE_MASK)
		goto out;
	if ((flags & MS_ASYNC) && (flags & MS_SYNC))
		goto out;
	error = -ENOMEM;
	len = (len + ~PAGE_MASK) & PAGE_MASK;
	end = start + len;
	if (end < start)
		goto out;
	error = 0;
	if (end == start)
		goto out;
	/*
	 * If the interval [start,end) covers some unmapped address ranges,
	 * just ignore them, but return -ENOMEM at the end.
	 */
	vma = find_vma(current->mm, start);
	unmapped_error = 0;
	for (;;) {
		/* Still start < end. */
		error = -ENOMEM;
		if (!vma)
			goto out;
		/* Here start < vma->vm_end. */
		if (start < vma->vm_start) {
			unmapped_error = -ENOMEM;
			start = vma->vm_start;
		}
		/* Here vma->vm_start <= start < vma->vm_end. */
		if (end <= vma->vm_end) {
			if (start < end) {
				error = msync_interval(vma, start, end, flags);
				if (error)
					goto out;
			}
			error = unmapped_error;
			goto out;
		}
		/* Here vma->vm_start <= start < vma->vm_end < end. */
		error = msync_interval(vma, start, vma->vm_end, flags);
		if (error)
			goto out;
		start = vma->vm_end;
		vma = vma->vm_next;
	}
out:
	up_read(&current->mm->mmap_sem);
	return error;
}

예제 #2

파일: msync.c 프로젝트: FatSunHYS/OSCourseDesign

asmlinkage long sys_msync(unsigned long start, size_t len, int flags)
{
	unsigned long end;
	struct vm_area_struct *vma;
	int unmapped_error = 0;
	int error = -EINVAL;
	int done = 0;

	if (flags & ~(MS_ASYNC | MS_INVALIDATE | MS_SYNC))
		goto out;
	if (start & ~PAGE_MASK)
		goto out;
	if ((flags & MS_ASYNC) && (flags & MS_SYNC))
		goto out;
	error = -ENOMEM;
	len = (len + ~PAGE_MASK) & PAGE_MASK;
	end = start + len;
	if (end < start)
		goto out;
	error = 0;
	if (end == start)
		goto out;
	/*
	 * If the interval [start,end) covers some unmapped address ranges,
	 * just ignore them, but return -ENOMEM at the end.
	 */
	down_read(&current->mm->mmap_sem);
	vma = find_vma(current->mm, start);
	if (!vma) {
		error = -ENOMEM;
		goto out_unlock;
	}
	do {
		unsigned long nr_pages_dirtied = 0;
		struct file *file;

		/* Here start < vma->vm_end. */
		if (start < vma->vm_start) {
			unmapped_error = -ENOMEM;
			start = vma->vm_start;
		}
		/* Here vma->vm_start <= start < vma->vm_end. */
		if (end <= vma->vm_end) {
			if (start < end) {
				error = msync_interval(vma, start, end, flags,
							&nr_pages_dirtied);
				if (error)
					goto out_unlock;
			}
			error = unmapped_error;
			done = 1;
		} else {
			/* Here vma->vm_start <= start < vma->vm_end < end. */
			error = msync_interval(vma, start, vma->vm_end, flags,
						&nr_pages_dirtied);
			if (error)
				goto out_unlock;
		}
		file = vma->vm_file;
		start = vma->vm_end;
		if ((flags & MS_ASYNC) && file && nr_pages_dirtied) {
			get_file(file);
			up_read(&current->mm->mmap_sem);
			balance_dirty_pages_ratelimited_nr(file->f_mapping,
							nr_pages_dirtied);
			fput(file);
			down_read(&current->mm->mmap_sem);
			vma = find_vma(current->mm, start);
		} else if ((flags & MS_SYNC) && file &&
				(vma->vm_flags & VM_SHARED)) {
			get_file(file);
			up_read(&current->mm->mmap_sem);
			error = do_fsync(file, 0);
			fput(file);
			down_read(&current->mm->mmap_sem);
			if (error)
				goto out_unlock;
			vma = find_vma(current->mm, start);
		} else {
			vma = vma->vm_next;
		}
	} while (vma && !done);
out_unlock:
	up_read(&current->mm->mmap_sem);
out:
	return error;
}