This patch adds the headers and helpers for the FreeBSD gntdev, used in order
to map grants from remote domains and to allocate grants on behalf of the
current domain.
Current code has been tested with the QEMU/Qdisk backend.
Signed-off-by: Akshay Jaggi <akshay1994.leo@gmail.com>
[ added dummy stub for osdep_gnttab_grant_copy ]
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Move PAGE_* back to {linux,freebsd}.c due to breakage in stubdom build.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
In a linux part an ioctl(gntdev, IOCTL_GNTDEV_GRANT_COPY, ..)
system call is invoked. In mini-os the operation is yet not
implemented. For the OSs that does not implement gnttab the
call of the grant copy operation causes abort.
Signed-off-by: Paulina Szubarczyk <paulinaszubarczyk@gmail.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
[ wei: modify this patch to use BUILD_BUG_ON in xen-tools/libs.h ]
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
In some cases this replaces an FD_CLOEXEC dance, in others it is new.
Linux has had O_CLOEXEC since 2.6.23 (October 2007), so we can rely on
it from Xen 4.7 I think. Some libc headers may still lack the
definition, so we take care of that if need be by defining to 0 (on
the premise that such an old glibc might barf on O_CLOEXEC even if the
kernel may or may not be so old).
All stable versions of FreeBSD support O_CLOEXEC (10.2, 9.3 and 8.4),
and we assume the libc there does too.
Remove various comments about having to take responsibility for this
(since really it is just hygiene, politeness, not a requirement) and
the reasons for using O_CLOEXEC seem pretty straightforward.
Backends for other OSes are untouched.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Cc: Roger.Pau@citrix.com
Cc: jbeulich@suse.com
In particular around error handling, behaviour on fork and the unmap
notification mechanism.
Behaviour of xengnttab_map_*grant_refs and xengntshr_share_pages on
partial failure has been confirmed/inferred (by inspection) on Linux
and Mini-os (the only two known implementations. Likewise the
behaviour of the notification mechanism has been confirmed/inferred
(by inspection) of the Linux implementation (currently the only
implementation) and libvchan (primary known user).
These updates are not folded into "tools: Refactor
/dev/xen/gnt{dev,shr} wrappers into libxengnttab." to try and reduce
the amount of non-movement changes in that patch.
While I'm not convinced by javadoc/doxygen cause the existing comments
which appear to use that syntax to have the appropriate /** marker.
Also fix a typo in a code comment.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Cc: Daniel De Graaf <dgdegra@tycho.nsa.gov>
These were wrong in the context of libxc before this code was
extracted, clean them up.
Also add some emacs magic blocks
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
libxengnttab will provide a stable API and ABI for accessing the
grant table devices.
The functions are moved into the xengnt{tab,shr} namespace to make a
clean break from libxc and avoid ambiguity regarding which interfaces
are stable.
All in-tree users are updated to use the new names.
Upon request (via #define XC_WANT_COMPAT_GNTTAB_API) libxenctrl will
provide a compat API for the old names. This is used by qemu-xen for
the time being. qemu-xen-traditional is updated in lockstep.
This leaves a few grant table related functions which go via privcmd
(GNTTABOP) rather than ioctls on the /dev/xen/gnt* devices in
libxenctrl. Specifically:
- xc_gnttab_get_version
- xc_gnttab_map_table_v1
- xc_gnttab_map_table_v2
- xc_gnttab_op
These functions do not appear to be needed by qemu-dm, qemu-pv
(provision of device model to HVM guests and PV backends respectively)
or by libvchan suggesting they are not needed by non-toolstack uses of
event channels.
The new library uses a version script to ensure that only expected
symbols are exported and to version them such that ABI guarantees can
be kept in the future.
After this change libxenvchan no longer needs to link against
libxenctrl. It still needs xenctrl.h in one file for xen_mb and
friends.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
[ ijc -- updated MINIOS_UPSTREAM_REVISION and QEMU_TRADITIONAL_REVISION ]
Roger Pau Monne
Paulina Szubarczyk
Ian Campbell