Commits
Ira Weiny committed c5d6c45e90c
mm/swap: fix release_pages() when releasing devmap pages release_pages() is an optimized version of a loop around put_page(). Unfortunately for devmap pages the logic is not entirely correct in release_pages(). This is because device pages can be more than type MEMORY_DEVICE_PUBLIC. There are in fact 4 types, private, public, FS DAX, and PCI P2PDMA. Some of these have specific needs to "put" the page while others do not. This logic to handle any special needs is contained in put_devmap_managed_page(). Therefore all devmap pages should be processed by this function where we can contain the correct logic for a page put. Handle all device type pages within release_pages() by calling put_devmap_managed_page() on all devmap pages. If put_devmap_managed_page() returns true the page has been put and we continue with the next page. A false return of put_devmap_managed_page() means the page did not require special processing and should fall to "normal" processing. This was found via code inspection while determining if release_pages() and the new put_user_pages() could be interchangeable.[1] [1] https://lkml.kernel.org/r/20190523172852.GA27175@iweiny-DESK2.sc.intel.com Link: https://lkml.kernel.org/r/20190605214922.17684-1-ira.weiny@intel.com Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>