Since Linux's git commit ceb90fa0a8008059ecbbf9114cb89dc71a730bb6,
the privcmd.h interface between Linux and libxc specifies two new
constants, PRIVCMD_MMAPBATCH_MFN_ERROR and
PRIVCMD_MMAPBATCH_PAGED_ERROR. These constants represent the error
codes encoded in the top nibble of an mfn slot passed to the legacy
MMAPBATCH ioctl.
In particular, libxenctrl checks for the equivalent of the latter
constant when dealing with paged out frames that might be the target
of a foreign map.
Previously, the relevant constant was defined in the domctl hypervisor
interface header (XEN_DOMCTL_PFINFO_PAGEDTAB). Because this
top-nibble encoding is a contract between the dom0 kernel and libxc,
a domctl.h definition is misplaced.
- Sync the privcmd.h header to that now available in upstream Linux
- Update libxc appropriately
- Remove the unnecessary constant in domctl.h
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Acked-by: Ian Campbell <ian.campbelL@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
These functions and the xc_gntshr device (/dev/xen/gntalloc on linux)
allow applications to create pages shared with other domains.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Normally, when a userspace process mapping a grant crashes, the domain
providing the reference receives no indication that its peer has
crashed, possibly leading to unexpected freezes or timeouts. This
function provides a notification of the unmap by signalling an event
channel and/or clearing a specific byte in the page.
This also unifies the 3 very similar grant-mapping osdep interfaces into
a single function instead of introducing yet another minor variation.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Replace all calls to xc_map_foreign_batch() where the caller doesn't
look at the passed in array to check for errors by calls to
xc_map_foreign_pages(). Replace all remaining calls by such to the
newly introduced xc_map_foreign_bulk().
As a sideband modification (needed while writing the patch to ensure
they're unused) eliminate unused parameters to
uncanonicalize_pagetable() and xc_map_foreign_batch_single(). Also
unmap live_p2m_frame_list earlier in map_and_save_p2m_table(),
reducing the peak amount of virtual address space required.
All supported OSes other than Linux continue to use the old ioctl for
the time being.
Also change libxc's MAJOR to 4.0 to reflect the API change.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
This patch adds the ability to set the number of slots that may be
used for mapping grant references, using the gntdev user-space grant
reference mapping driver.
Signed-off-by: Derek Murray <Derek.Murray@cl.cam.ac.uk>
Andres Lagar-Cavilla