When adding locking to tools/libs/evtchn/minios.c a semaphore was
used. This can result in deadlocks, as the lock is taken inside the
event handler, which can interrupt an already locked region.
The fix is rather simple, as Mini-OS is supporting a single vcpu
only. So instead of the semaphore it is enough to disable interrupts
when operating on the port list.
Fixes: bc4fe94a69 ("ools/libs/evtchn: replace assert()s in stubdom with proper locking")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
In tools/libs/evtchn/minios.c there are assert()s for the current
thread being the main thread when binding an event channel.
As Mini-OS is supporting multiple threads, there is no real reason
why the binding shouldn't be allowed to happen in any other thread.
Drop the assert()s and replace them with proper locking of the
port_list.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
A leading underscore is used to indicate auto generated headers, and
the clean use of 'rm -f _*.h' will remove those. _xen_list.h also
uses a leading underscore, but is checked in the repo and as such
cannot be removed as part of the clean rule.
Fix this by dropping the leading underscore, so that the header is not
removed.
Fixes: a03b3552d4 ('libs,tools/include: Clean "clean" targets')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Setting errno to a negative value makes no sense.
Fixes: 6b6500b3cb ("tools/libs/evtchn: Add support for restricting a handle")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Instead of including xen-external/bsd-sys-queue.h use the header
_xen_list.h in minios.c.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
It is possible now to delete minios_evtchn_close_fd() and the extern
declaration of event_queue.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Mini-OS and libevtchn are using implementation details of each other.
Change that by letting libevtchn use the new alloc_file_type() and
get_file_from_fd() function and the generic dev pointer of struct file
from Mini-OS.
By using private struct declarations Mini-OS will be able to drop the
libevtchn specific definitions of struct evtchn_port_info and
evtchn_port_list in future. While at it use bool for "pending" and
"bound".
Switch to use xce as function parameter instead of fd where possible.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
struct xenevtchn_handle is common in private.h, meaning that xenevtchn_fd()
has exactly one correct implementation.
Implement it in core.c, rather than identically for each OS. This matches all
other libraries (call, gnttab, gntshr) which implement an fd getter.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Today the file descriptor for the access of the event channel driver
is being closed in case of exec(2). For the support of live update of
a daemon using libxenevtchn this can be problematic, so add a way to
keep that file descriptor open.
Add support of a flag XENEVTCHN_NO_CLOEXEC for xenevtchn_open() which
will result in _not_ setting O_CLOEXEC when opening the event channel
driver node.
The caller can then obtain the file descriptor via xenevtchn_fd().
Add an alternative open function xenevtchn_fdopen() which takes that
file descriptor as an additional parameter. This allows to allocate a
xenevtchn_handle and to associate it with that file descriptor.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Wei Liu <wl@xen.org>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Propagate the flags parameter of xenevtchn_open() to the OS-specific
handlers in order to enable handling them there.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
There is a mixture of different styles in libxenevtchn. Use the
standard xen style only.
No functional change.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
There are several places in xenstore-stubdom where newlines at the end
of messages on the console are missing. Add them.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Implement support for restricting evtchn handles to a particular domain
on Linux by calling the IOCTL_EVTCHN_RESTRICT_DOMID ioctl (support added
in Linux v4.8).
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Release-acked-by: Julien Grall <julien.grall@linaro.org>
Otherwise the name clashes with the libxc evtchn_compat use of the
name (which is compat, so can't really change), and triggers an error
with older gcc relating to redefining typedefs (which are not allowed
per the spec, but which are tolerated by newer gcc)
None of qemu-trad, qemu-xen or mini-os actually use this type, so this
should be fine. Note that the library API is not actually stable until
4.7 is releases.
Reported-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Wei Liu <wei.liu2@citrix.com>
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 ]
libxenevtchn will provide a stable API and ABI for accessing the
evtchn device.
The functions are moved into the xenevtchn 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_EVTCHN_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 event channel related functions which go via privcmd
(EVTCHNOP) rather than ioctls on the /dev/xen/evtchn device in
libxenctrl. Specifically:
- xc_evtchn_alloc_unbound
- xc_evtchn_reset
- xc_evtchn_status
Note that xc_evtchn_alloc_unbound's functionality is also provided by
xenevtchn_bind_unbound_port() (née xc_evtchn_bind_unbound_port) and is
probably redundant.
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. QEMU does use these in hw/xenpv/xen_domainbuild.c but
that is a "toolstack use".
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>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
[ ijc -- updated MINIOS_UPSTREAM_REVISION and QEMU_TRADITIONAL_REVISION ]
Juergen Gross
Roger Pau Monné
Andrew Cooper
Ross Lagerwall
Ian Campbell