- /*
- * mmap_sem is currently held for write. Downgrade the write
- * lock to a read lock so that other faults, mmap scans, ...
- * while we fault in all pages.
- */
- downgrade_write(&mm->mmap_sem);
-
- ret = __mlock_vma_pages_range(vma, start, end, 1);
-
- /*
- * Need to reacquire mmap sem in write mode, as our callers
- * expect this. We have no support for atomically upgrading
- * a sem to write, so we need to check for ranges while sem
- * is unlocked.
- */
- up_read(&mm->mmap_sem);
- /* vma can change or disappear */
- down_write(&mm->mmap_sem);
- *prev = find_vma(mm, start);
- /* non-NULL *prev must contain @start, but need to check @end */
- if (!(*prev) || end > (*prev)->vm_end)
- ret = -ENOMEM;
- else if (ret > 0) {
- mm->locked_vm -= ret;
- ret = 0;
- } else
- ret = __mlock_posix_error_return(ret); /* translate if needed */
+ vma->vm_flags = newflags;
+ ret = __mlock_vma_pages_range(vma, start, end);
+ if (ret < 0)
+ ret = __mlock_posix_error_return(ret);