• David Hildenbrand's avatar
    mm: convert PG_balloon to PG_offline · ec61b9e9
    David Hildenbrand authored
    PG_balloon was introduced to implement page migration/compaction for pages
    inflated in virtio-balloon.  Nowadays, it is only a marker that a page is
    part of virtio-balloon and therefore logically offline.
    We also want to make use of this flag in other balloon drivers - for
    inflated pages or when onlining a section but keeping some pages offline
    (e.g.  used right now by XEN and Hyper-V via set_online_page_callback()).
    We are going to expose this flag to dump tools like makedumpfile.  But
    instead of exposing PG_balloon, let's generalize the concept of marking
    pages as logically offline, so it can be reused for other purposes later
    Rename PG_balloon to PG_offline.  This is an indicator that the page is
    logically offline, the content stale and that it should not be touched
    (e.g.  a hypervisor would have to allocate backing storage in order for
    the guest to dump an unused page).  We can then e.g.  exclude such pages
    from dumps.
    We replace and reuse KPF_BALLOON (23), as this shouldn't really harm (and
    for now the semantics stay the same).  In following patches, we will make
    use of this bit also in other balloon drivers.  While at it, document
    Link: http://lkml.kernel.org/r/20181119101616.8901-3-david@redhat.comSigned-off-by: default avatarDavid Hildenbrand <david@redhat.com>
    Acked-by: default avatarKonstantin Khlebnikov <koct9i@gmail.com>
    Acked-by: default avatarMichael S. Tsirkin <mst@redhat.com>
    Acked-by: default avatarPankaj gupta <pagupta@redhat.com>
    Cc: Jonathan Corbet <corbet@lwn.net>
    Cc: Alexey Dobriyan <adobriyan@gmail.com>
    Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
    Cc: Christian Hansen <chansen3@cisco.com>
    Cc: Vlastimil Babka <vbabka@suse.cz>
    Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
    Cc: Stephen Rothwell <sfr@canb.auug.org.au>
    Cc: Matthew Wilcox <willy@infradead.org>
    Cc: Michal Hocko <mhocko@suse.com>
    Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
    Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
    Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
    Cc: Miles Chen <miles.chen@mediatek.com>
    Cc: David Rientjes <rientjes@google.com>
    Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
    Cc: Arnd Bergmann <arnd@arndb.de>
    Cc: Baoquan He <bhe@redhat.com>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
    Cc: Dave Young <dyoung@redhat.com>
    Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Cc: Haiyang Zhang <haiyangz@microsoft.com>
    Cc: Juergen Gross <jgross@suse.com>
    Cc: Julien Freche <jfreche@vmware.com>
    Cc: Kairui Song <kasong@redhat.com>
    Cc: "K. Y. Srinivasan" <kys@microsoft.com>
    Cc: Len Brown <len.brown@intel.com>
    Cc: Lianbo Jiang <lijiang@redhat.com>
    Cc: Michal Hocko <mhocko@kernel.org>
    Cc: Nadav Amit <namit@vmware.com>
    Cc: Omar Sandoval <osandov@fb.com>
    Cc: Pavel Machek <pavel@ucw.cz>
    Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
    Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
    Cc: Stefano Stabellini <sstabellini@kernel.org>
    Cc: Stephen Hemminger <sthemmin@microsoft.com>
    Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
    Cc: Xavier Deguillard <xdeguillard@vmware.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
page-types.c 30.4 KB