Alistair Popple wrote: > Prior to freeing a block file systems supporting FS DAX must check > that the associated pages are both unmapped from user-space and not > undergoing DMA or other access from eg. get_user_pages(). This is > achieved by unmapping the file range and scanning the FS DAX > page-cache to see if any pages within the mapping have an elevated > refcount. > > This is done using two functions - dax_layout_busy_page_range() which > returns a page to wait for the refcount to become idle on. Rather than > open-code this introduce a common implementation to both unmap and > wait for the page to become idle. > > Signed-off-by: Alistair Popple <apopple@xxxxxxxxxx> > > --- [..] Whoops, I hit send on the last mail before seeing this: > diff --git a/mm/madvise.c b/mm/madvise.c > index 49f3a75..1f4c99e 100644 > --- a/mm/madvise.c > +++ b/mm/madvise.c This hunk needs to move to the devmap removal patch, right? With that fixed up the Reviewed-by still stands.
