Closing the fd before unhooking it from the list runs the risk that a
concurrent thread calls xentoolcore_restrict_all will operate on the
old fd value, which might refer to a new fd by then. So we need to do
it in the other order.
Sadly this weakens the guarantee provided by xentoolcore_restrict_all
slightly, but not (I think) in a problematic way. It would be
possible to implement the previous guarantee, but it would involve
replacing all of the close() calls in all of the individual osdep
parts of all of the individual libraries with calls to a new function
which does
dup2("/dev/null", thing->fd);
pthread_mutex_lock(&handles_lock);
thing->fd = -1;
pthread_mutex_unlock(&handles_lock);
close(fd);
which would be terribly tedious.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Release-acked-by: Julien Grall <julien.grall@linaro.org>
This necessitates adding $(CFLAGS_xeninclude) to all the depending
libraries (which can be done via Rules.mk), so that the definition of
domid_t (in xen.h) can be found.
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
The new function repeats the behavior of the first version
except it has an extended list of arguments which are subsequently
passed to mmap() call.
This is needed for QEMU depriviledging.
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Commit 8ef5f344d0 "tools/libxendevicemodel: add a call to restrict the
handle" added a function to the devicemodel interface to restrict
operations through the API to a specific domain, where a capable under-
lying privcmd driver exists.
This patch adds similar functionality to the xenforeignmemory API. This
will be necessary (as much as xendevicemodel restriction) for limiting
the scope of device models to specific domains.
NOTE: My patch to the linux kernel [1] added the appropriate checks to
the foreign memory ioctls.
[1] https://git.kernel.org/cgit/linux/kernel/git/ostr/linux.git/commit/?id=4610d240
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Otherwise the osdep close on the error path touches an uninitialised
varialble.
CID: 1351231 (foreignmemory) and 1351230 (call)
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Coverity rightly points out that checking for ret == NULL and then
calling osdep unmap(ret) is wrong.
The intention on this code path is to turn partial failure into total
failure when the err argument is NULL, so we want to take this patch
whenever ret is _non_ NULL (and err_to_free is set, indicating err was
NULL).
CID: 1351219
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
By having the "num" argument before the page and error arrays we can
potentially use a variable-length-array argument ("int pages[num]") in
the function prototype.
However VLAs are a C99 feature and we are currently targetting C89 and
later, so we don't actually make use of this here, merely arrange that
we can switch to VLAs in the future without changing the function ABI.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
The existing xc_map_foreign_bulk-like interface encourages callers to
miss error checking for partial failure (by forgetting to scan the err
array).
Add support for passing err==NULL which behaves in a
xc_map_foreign_pages-like manner and returns a global error for any
failure.
While documenting this also clarify the overall behaviour and the
behaviour with err!=NULL.
With this the compat wrapper of xc_map_foreign_pages() can be
simplified.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
libxenforeignmemory will provide a stable API and ABI for mapping
foreign domain memory (subject to appropriate privileges).
The new library exposes an interface equivalent to
xc_map_foreign_memory_bulk, which all the other
xc_map_foreign_memory_* functions (which remain in libxc) are
implemented in terms of.
Upon request (via #define XC_WANT_COMPAT_MAP_FOREIGN_API) libxenctrl
will provide a compat API for the old names. This is used by qemu-xen
and qemu-trad as well as various in tree things (which required
de-dupping various #includes in some too to get the #define before the
first).
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
[ ijc -- updated MINIOS_UPSTREAM_REVISION and QEMU_TRADITIONAL_REVISION ]
Paul Durrant
Ian Jackson
Wei Liu
Igor Druzhinin
Ian Campbell