The source code base needs to be adapted as well. Some files
include virutil.h just for the string related functions (here,
the include is substituted to match the new file), some include
virutil.h without any need (here, the include is removed), and
some require both.
Some FDs may not implement fdatasync() functionality,
e.g. pipes. In that case EINVAL or EROFS is returned.
We don't want to fail then nor report any error.
Reported-by: Christophe Fergeau <cfergeau@redhat.com>
Currently, when we are doing (managed) save, we insert the
iohelper between the qemu and OS. The pipe is created, the
writing end is passed to qemu and the reading end to the
iohelper. It reads data and write them into given file. However,
with write() being asynchronous data may still be in OS
caches and hence in some (corner) cases, all migration data
may have been read and written (not physically though). So
qemu will report success, as well as iohelper. However, with
some non local filesystems, where ENOSPACE is polled every X
time units, we may get into situation where all operations
succeeded but data hasn't reached the disk. And in fact will
never do. Therefore we ought sync caches to make sure data
has reached the block device on remote host.
https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.
* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/; If/. If/
All callers used the same initialization seed (well, the new
viratomictest forgot to look at getpid()); so we might as well
make this value automatic. And while it may feel like we are
giving up functionality, I documented how to get it back in the
unlikely case that you actually need to debug with a fixed
pseudo-random sequence. I left that crippled by default, so
that a stray environment variable doesn't cause a lack of
randomness to become a security issue.
* src/util/virrandom.c (virRandomInitialize): Rename...
(virRandomOnceInit): ...and make static, with one-shot call.
Document how to do fixed-seed debugging.
* src/util/virrandom.h (virRandomInitialize): Drop prototype.
* src/libvirt_private.syms (virrandom.h): Don't export it.
* src/libvirt.c (virInitialize): Adjust caller.
* src/lxc/lxc_controller.c (main): Likewise.
* src/security/virt-aa-helper.c (main): Likewise.
* src/util/iohelper.c (main): Likewise.
* tests/seclabeltest.c (main): Likewise.
* tests/testutils.c (virtTestMain): Likewise.
* tests/viratomictest.c (mymain): Likewise.
Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)
You should have received a copy of the GNU General Public License
along with Foobar. If not, see <http://www.gnu.org/licenses/>.
This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').
Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:
src/security/security_selinux.h
src/security/security_driver.h
src/security/security_selinux.c
src/security/security_apparmor.h
src/security/security_apparmor.c
src/security/security_driver.c
The old virRandom() API was not generating good random numbers.
Replace it with a new API virRandomBits which instead of being
told the upper limit, gets told the number of bits of randomness
required.
* src/util/virrandom.c, src/util/virrandom.h: Add virRandomBits,
and move virRandomInitialize
* src/util/util.h, src/util/util.c: Delete virRandom and
virRandomInitialize
* src/libvirt.c, src/security/security_selinux.c,
src/test/test_driver.c, src/util/iohelper.c: Update for
changes from virRandom to virRandomBits
* src/storage/storage_backend_iscsi.c: Remove bogus call
to virRandomInitialize & convert to virRandomBits
When aligning you need to clear the bits in the mask and leave the
others aside. Likely this code has never run, and will never run.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Required for a coming patch where iohelper will operate on O_DIRECT
fds. There, the user-space memory must be aligned to file system
boundaries (at least 512, but using page-aligned works better, and
some file systems prefer 64k). Made tougher by the fact that
VIR_ALLOC won't work on void *, but posix_memalign won't work on
char * and isn't available everywhere.
This patch makes some simplifying assumptions - namely, output
to an O_DIRECT fd will only be attempted on an empty seekable
file (hence, no need to worry about preserving existing data
on a partial block, and ftruncate will work to undo the effects
of having to round up the size of the last block written), and
input from an O_DIRECT fd will only be attempted on a complete
seekable file with the only possible short read at EOF.
* configure.ac (AC_CHECK_FUNCS_ONCE): Check for posix_memalign.
* src/util/iohelper.c (runIO): Use aligned memory, and handle
quirks of O_DIRECT on last write.
Rather than making the iohelper subject to a race in reopening
the file, it is nicer to pass an already-open fd by inheritance.
The old synopsis form must continue to work - if someone updates
their libvirt package and installs a new libvirt_iohelper but
without restarting the old libvirtd daemon, then the daemon can
still make calls using the old syntax but the new iohelper.
* src/util/iohelper.c (runIO): Split code for open...
(prepare): ...to new function.
(usage): Update synopsis.
(main): Allow alternate calling form.
* src/fdstream.c (virFDStreamOpenFileInternal): Use alternate form.
Enforce the recent flags cleanups - we want to use 'unsigned int flags'
in any of our APIs (except where backwards compatibility is important,
in the public migration APIs), and that all flags are checked for
validity (except when there are stub functions that completely
ignore the flags argument).
There are a few minor tweaks done here to avoid false positives:
signed arguments passed to open() are renamed oflags, and flags
arguments that are legitimately ignored are renamed flags_unused.
* cfg.mk (sc_flags_usage): New rule.
(exclude_file_name_regexp--sc_flags_usage): And a few exemptions.
(sc_flags_debug): Tweak wording.
* src/util/iohelper.c (runIO, main): Rename variable.
* src/util/util.c (virSetInherit): Likewise.
* src/fdstream.h (virFDStreamOpenFile, virFDStreamCreateFile):
Likewise.
* src/fdstream.c (virFDStreamOpenFileInternal)
(virFDStreamOpenFile, virFDStreamCreateFile): Likewise.
* src/util/command.c (virExecWithHook) [WIN32]: Likewise.
* src/util/util.c (virFileOpenAs, virDirCreate) [WIN32]: Likewise.
* src/locking/lock_manager.c (virLockManagerPluginNew)
[!HAVE_DLFCN_H]: Likewise.
* src/locking/lock_driver_nop.c (virLockManagerNopNew)
(virLockManagerNopAddResource, virLockManagerNopAcquire)
(virLockManagerNopRelease, virLockManagerNopInquire): Likewise.
This is needed if we want to transfer a temporary file. If the
transfer is done with iohelper, we might run into a race condition,
where we unlink() file before iohelper is executed.
* src/fdstream.c, src/fdstream.h,
src/util/iohelper.c: Add new option
* src/lxc/lxc_driver.c, src/qemu/qemu_driver.c,
src/storage/storage_driver.c, src/uml/uml_driver.c,
src/xen/xen_driver.c: Expand existing function calls
The O_NONBLOCK flag doesn't work as desired on plain files
or block devices. Introduce an I/O helper program that does
the blocking I/O operations, communicating over a pipe that
can support O_NONBLOCK
* src/fdstream.c, src/fdstream.h: Add non-blocking I/O
on plain files/block devices
* src/Makefile.am, src/util/iohelper.c: I/O helper program
* src/qemu/qemu_driver.c, src/lxc/lxc_driver.c,
src/uml/uml_driver.c, src/xen/xen_driver.c: Update for
streams API change
