Commit Graph
12 Commits
Author SHA1 Message Date
Ian Campbell 7db1f6a67d tools: libxencall/foreignmemory: initialise handle->fd
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>
2016-02-03 11:23:43 +00:00
Ian Campbell cc449379d9 libxenforeignmemory: handle partial failure correctly
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>
2016-02-03 11:23:08 +00:00
Ian Campbell 84e0616a50 tools: avoid redefinition of typedefs
When splitting out various functionality from libxc into tools/libs/*
I attempted to make it possible to avoid callers being unnecessarily
exposed to the xentoollog interface by providing a typedef of the
xentoollog_logger handle in each of the headers.

However such typedefs are not allowed in C, instead it is necessary to
forward declare the struct and then use the struct xentoollog_logger
variant in the prototypes.

It appears that older gcc (e.g. 4.4) complains about this issue while
newer ones (e.g. 4.9) are more tolerant unless -pedantic-errors is
used, this was a deliberate change
https://gcc.gnu.org/git/?p=gcc.git;a=commitdiff;h=ce3765bf44e49ef0568a1ad4a0b7f807591d6412

As well as tools/libs/* it is also now necessary to give libvchan the
same treatment, since it previously inhereted the typedef via one of
tools/libs/*.

Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2016-01-25 15:45:52 +00:00
Ian Campbell d322b7f4c2 tools/libs/*: freebsd remove unused code
"tools/libs/*: Use O_CLOEXEC on Linux and FreeBSD" left some dead code
in the FreeBSD case, which breaks the build on that platform.

Also fix a typo "uint_32".

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2016-01-25 14:20:08 +00:00
Ian Campbell 0831774c81 tools/libs/*: Use O_CLOEXEC on Linux and FreeBSD
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
2016-01-22 12:24:22 +00:00
Ian Campbell bfddc736f8 tools/libs: Clean up hard tabs.
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>
2016-01-22 12:24:20 +00:00
Ian Campbell cf8c4d3d13 tools/libs/foreignmemory: pull array length argument to map forward
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>
2016-01-22 12:24:19 +00:00
Ian Campbell bd1c1ea440 tools/libs/foreignmemory: Support err == NULL to map.
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>
2016-01-22 12:24:18 +00:00
Ian Campbell c4f9e14dea tools/libs/foreignmemory: Mention restrictions on fork in docs.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2016-01-22 12:24:18 +00:00
Ian Campbell 9391f25767 tools/libs/foreignmemory: use size_t for size arguments.
Surprisingly it appears no callers need updating.

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>
2016-01-22 12:24:18 +00:00
Ian Campbell 0be403a41f tools/libs/foreignmemory: provide xenforeignmemory_unmap.
And require it be used instead of direct munmap.

This will allow e.g. Valgrind hooks to help track incorrect use of
foreign mappings.

Switch all uses of xenforeignmemory_map to use
xenforeignmemory_unmap, not that foreign mappings via the libxc compat
xc_map_foreign_* interface will not take advantage of this and will
need converting.

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>
2016-01-22 12:24:18 +00:00
Ian Campbell 3248691679 tools: Refactor foreign memory mapping into libxenforeignmemory
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 ]
2016-01-22 12:24:03 +00:00