Commit Graph
10 Commits
Author SHA1 Message Date
Ian Campbell 3e9b0d5408 tools: Refactor hypercall calling wrappers into libxencall.
libxencall will provide a stable API and ABI for calling hypercalls
(although those hypercalls themselves may not have a stable API). As
well as the hypercall buffer infrastructure needed in order to safely
provide pointer arguments to hypercalls.

libxenctrl encapsulates a instance of this interface, so users of that
library are not currently subjected to any actual changes. However all
hypercalls made internally by libxc now use the correct interface. It
is expected that most users of this library will be other libraries
providing a higher level interface, rather than applications directly.

Only the basic functionality to allocate hypercall safe memory is
moved, the type safe stuff and bounce buffers remain in libxc.

Note that the functionality to map foreign pages using privcmd is not
yet moved, meaning that an xc_interface will now contain two open
privcmd file descriptors. Foreign memory mapping is logically separate
functionality and will be moved into its own library.

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.

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 ]
2016-01-22 12:23:30 +00:00
Ian Campbell 7a3543df83 tools/libxc: Remove osdep indirection for privcmd
The alternative backend (a xen-api/xapi shim) is no longer around and
so this stuff is now just baggage which is getting in the way of
refactoring libxenctrl.

Nested virt probably suffices for this use case now.

This was the last component of the osdep infrastructure, so all the
dynamic loading etc stuff all falls away too.

As part of this I was forced to investigate the twisty
xc_map_foreign_* maze, which I have added to the
toolstack-library-apis doc in the hopes of doing something sensible.

NetBSD and Solaris now call xc_map_foreign_bulk_compat directly from
their xc_map_foreign_bulk, which could have been achieved by using
some ifdefs around a renamed function. This will fall out in the wash
when these functions move to their own library.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: David Scott <dave.scott@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2016-01-22 12:22:38 +00:00
Wei Liu 1e72eebd21 libxc: fix comment in xc__hypercall_bounce_pre
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
2016-01-19 16:14:58 +00:00
Ian Campbell 443701ef0c Replace FSF street address with canonical URL
As recommended in http://www.gnu.org/licenses/gpl-howto.en.html.

This is the result of:
$ git grep -El Mass\|Temple\|Franklin | xargs ./fsf.pl

Where fsf.pl is:
    #!/usr/bin/perl -w -pi.bak -0777
    my $repl = 'If not, see <http://www.gnu.org/licenses/>.';
    my $br = qr/(?:\s*\n\s*(?:[\*\#]|\/\/|\.\\" )?\s*|\s+)/;

    my $inwt = qr/[Ii]f${br}not,${br}write${br}(?:to${br})?the${br}Free${br}Software${br}Foundation,(?:${br}Inc\.,)?/;

    my $mass = qr/675${br}Mass${br}Ave,?${br}Cambridge,?${br}MA${br}02139,?${br}USA,?\.?/;
    my $franklin = qr/51${br}Franklin${br}St(?:reet)?(?:,${br}| - )Fifth${br}Floor,?${br}Boston,?${br}MA,?${br}02110-1301,?${br}USA,?\.?/;
    my $temple = qr/59${br}Temple${br}Place(?:,${br}| - )Suite${br}330,?${br}Boston,?${br}MA,?${br}021110?-1307,?${br}USA,?\.?/;

    s|$inwt$br$mass|$repl|m;
    s|$inwt$br$franklin|$repl|m;
    s|$inwt$br$temple|$repl|m;

The only remaining mentions of these addresses are in COPYING files which I
haven't touched.

Some of the changed files are imports from elsewhere, however
filtering them out is tricky, I think it is tolerable to have these
files be modified here and then perhaps reverted on the next sync,
since it's only 1-2 lines and obvious what is going on.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
2015-07-29 11:14:07 +01:00
Konrad Rzeszutek Wilk e12c6e8d18 libxc: Propagate errno from hypercall instead of anything else.
After we have done the hypercall - the errno has the failure
code. However our usage of pthread and munmap can trigger them
to manipulate the errno with their failure values. That would
be bad as what we care about is just the hypercall error value.

Another solution to this would be to save the 'errno' from
pthread/munmap/madvise as an extra parameter to be analyzed
later. However the call-sites above us do not care about it.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
2015-03-20 16:04:35 +00:00
David Vrabel e07d1cb67b libxc: add hypercall buffer arrays
Hypercall buffer arrays are used when a hypercall takes a variable
length array of buffers.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Don Slutz <dslutz@verizon.com>
Tested-by: Don Slutz <dslutz@verizon.com>
Acked-by: Keir Fraser <keir@xen.org>
2013-11-12 11:46:39 +01:00
David Vrabel 82639998a5 Fix emacs local variable block to use correct C style variable.
The emacs variable to set the C style from a local variable block is
c-file-style, not c-set-style.

Signed-off-by: David Vrabel <david.vrabel@citrix.com
2013-02-21 16:12:46 +00:00
Ian Campbell 44baceec2d libxc: osdep: convert hypercall buffer allocation
This will allow us to use OS specific interfaces to ensure that the
allocated memory is safe for use as a hypercall buffer in the future.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
2011-03-11 18:18:18 +00:00
Ian Campbell 04d1f61a1f libxc: maintain a small, per-handle, cache of hypercall buffer memory
Constantly m(un)locking memory can have significant overhead on
systems with large numbers of CPUs. This was previously fixed by
20841:fbe8f32fa257 but this was dropped during the transition to
hypercall buffers.

Introduce a small cache of single page hypercall buffer allocations
which can be resused to avoid this overhead.

Add some statistics tracking to the hypercall buffer allocations.

The cache size of 4 was chosen based on these statistics since they
indicated that 2 pages was sufficient to satisfy all concurrent single
page hypercall buffer allocations seen during "xl create", "xl
shutdown" and "xl destroy" of both a PV and HVM guest therefore 4
pages should cover the majority of important cases.

This fixes http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=1719.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Reported-by: Zheng, Shaohui <shaohui.zheng@intel.com>
Tested-by: Haitao Shan <maillists.shan@gmail.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
2011-02-01 19:26:36 +00:00
Ian Campbell b545e27bc6 libxc: infrastructure for hypercall safe data buffers.
(Modified version of this patch, with updated #includes in
xc_hcall_buf.c to fix stubdomain build.)

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
2010-10-26 12:11:37 +01:00