Allow a 'configFile' parameter to be passed into the lock
drivers to provide configuration. Wire up the QEMU driver
to pass in file names '/etc/libvirt/qemu-$NAME.conf
eg qemu-sanlock.conf
* src/locking/lock_driver.h, src/locking/lock_driver_nop.c,
src/locking/lock_driver_sanlock.c, src/locking/lock_manager.c,
src/locking/lock_manager.h: Add configFile parameter
* src/qemu/qemu_conf.c: Pass in configuration file path to
lock driver plugins
The libvirt sanlock plugin is intentionally leaking a file
descriptor to QEMU. To enable QEMU to use this FD under
SELinux, it must be labelled correctly. We dont want to use
the svirt_image_t for this, since QEMU must not be allowed
to actually use the FD. So instead we label it with svirt_t
using virSecurityManagerSetProcessFDLabel
* src/locking/domain_lock.c, src/locking/domain_lock.h,
src/locking/lock_driver.h, src/locking/lock_driver_nop.c,
src/locking/lock_driver_sanlock.c, src/locking/lock_manager.c,
src/locking/lock_manager.h: Optionally pass an FD back to
the hypervisor for security driver labelling
* src/qemu/qemu_process.c: label the lock manager plugin
FD with the process label
Done as a separate commit to make backporting the next patch easier.
We are already using "intprops.h", but this makes it explicit.
* .gnulib: Update, for syntax-check fix.
* bootstrap.conf (gnulib_modules): Make intprops use explicit.
* src/locking/domain_lock.c (includes): Drop unused header.
* src/nwfilter/nwfilter_learnipaddr.c (includes): Use "", not <>,
for gnulib.
When virLockDriverAcquire is invoked during hotplug the state
parameter will be left as NULL.
* src/locking/lock_driver_nop.c,
src/locking/lock_driver_sanlock.c: Don't reference NULL state
parameter
Refactoring of the lock manager hotplug methods lost the
ret = 0 assignment for successful return path
* src/locking/domain_lock.c: Add missing ret = 0 assignments
In between fork and exec, a connection to sanlock is acquired
and the socket file descriptor is intionally leaked to the
child process. sanlock watches this FD for POLL_HANGUP to
detect when QEMU has exited. We don't want a rogus/compromised
QEMU from issuing sanlock RPC calls on the leaked FD though,
since that could be used to DOS other guests. By calling
sanlock_restrict() on the socket before exec() we can lock
it down.
* configure.ac: Check for sanlock_restrict API
* src/locking/domain_lock.c: Restrict lock acquired in
process startup phase
* src/locking/lock_driver.h: Add VIR_LOCK_MANAGER_ACQUIRE_RESTRICT
* src/locking/lock_driver_sanlock.c: Add call to sanlock_restrict
when requested by VIR_LOCK_MANAGER_ACQUIRE_RESTRICT flag
Sanlock is a project that implements a disk-paxos locking
algorithm. This is suitable for cluster deployments with
shared storage.
* src/Makefile.am: Add dlopen plugin for sanlock
* src/locking/lock_driver_sanlock.c: Sanlock driver
* configure.ac: Check for sanlock
* libvirt.spec.in: Add a libvirt-lock-sanlock RPM
To facilitate use of the locking plugins from hypervisor drivers,
introduce a higher level API for locking virDomainObjPtr instances.
In includes APIs targetted to VM startup, and hotplug/unplug
* src/Makefile.am: Add domain lock API
* src/locking/domain_lock.c, src/locking/domain_lock.h: High
level API for domain locking
To allow hypervisor drivers to assume that a lock driver impl
will be guaranteed to exist, provide a 'nop' impl that is
compiled into the library
* src/Makefile.am: Add nop driver
* src/locking/lock_driver_nop.c, src/locking/lock_driver_nop.h:
Nop lock driver implementation
* src/locking/lock_manager.c: Enable direct access of 'nop'
driver, instead of dlopen()ing it.
Define the basic framework lock manager plugins. The
basic plugin API for 3rd parties to implemented is
defined in
src/locking/lock_driver.h
This allows dlopen()able modules for alternative locking
schemes, however, we do not install the header. This
requires lock plugins to be in-tree allowing changing of
the lock manager plugin API in future.
The libvirt code for loading & calling into plugins
is in
src/locking/lock_manager.{c,h}
* include/libvirt/virterror.h, src/util/virterror.c: Add
VIR_FROM_LOCKING
* src/locking/lock_driver.h: API for lock driver plugins
to implement
* src/locking/lock_manager.c, src/locking/lock_manager.h:
Internal API for managing locking
* src/Makefile.am: Add locking code
