On Fri, May 24, 2019 at 8:07 AM Souptick Joarder <jrdr.li...@gmail.com> wrote: > > > > Taking a quick look now, by the way, why does vm_map_pages_zero() (and > > > __vm_map_pages() etc.) get a pointer to an array instead of a pointer > > > to the first element? > > For this particular driver, one page is getting mapped into vma. But > there are other > places where a entire page array ( with more than one pages) mapped into > vma. That's the reason to pass pointer to an array and do rest of the > operations > inside __vm_map_pages().
Ah, "pointer to array of source kernel pages" made me think the actual `struct page`s were the ones consecutive in memory, not the pointers. Maybe "array of page pointers" is more clear. > > Also, in __vm_map_pages(), semantically w.r.t. to the comment, > > shouldn't the first check test for equality too? (i.e. for vm_pgoff == > > num)? (even if such case fails in the second test anyway). > > Sorry, didn't get it. Do you mean there should be a separate check for > *vm_pgoff == num* ? No, that the first check should be widened. I will send a patch. Cheers, Miguel
