Using error_is_set(ERRP) to find out whether a function failed is
either wrong, fragile, or unnecessarily opaque. It's wrong when ERRP
may be null, because errors go undetected when it is. It's fragile
when proving ERRP non-null involves a non-local argument. Else, it's
unnecessarily opaque (see commit 84d18f0).
The error_is_set(errp) in the guest agent command handler functions
are merely fragile, because all chall chains (do_qmp_dispatch() via
the generated marshalling functions) pass a non-null errp argument.
Make the code more robust and more obviously correct: receive the
error in a local variable, then propagate it through the parameter.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Using error_is_set(errp) to check whether a function call failed is
fragile: it breaks when errp is null. ga_get_fd_handle() and
guest_file_handle_add() don't return a useful value when they fail,
but that's just stupid. Fix that, and check them instead. As far
as I can tell, errp can't be null there, but this is more robust and
more obviously correct.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
We mixed the use of "guest time", "system time", "hardware time",
"RTC" in documentation, it's unclear.
This patch just added two remarks of RTC and replace two "guest time"
by "guest's system time".
Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
qmp_guest_file_seek() allocates memory for a GuestFileRead object
instead of the GuestFileSeek object it actually uses. Harmless,
because the GuestFileRead is slightly larger.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
As the description to the guest-set-time states, the command is
there to ease time synchronization after resume. If guest was
suspended for longer period of time, its system time can go off
so badly, that even NTP refuses to set it. That's why the command
was invented: to give users chance to set the time (not
necessarily 100% correct). However, there's is no real need for
us to require users to pass an arbitrary time. Especially if we
can read the correct value from RTC (boiling down to reading
host's time). Hence this commit enables logic:
guest-set-time() == guest-set-time($now_from_rtc)
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
error_is_set(&var) is the same as var != NULL, but it takes
whole-program analysis to figure that out. Unnecessarily hard for
optimizers, static checkers, and human readers. Dumb it down to
obvious.
Gets rid of several dozen Coverity false positives.
Note that the obvious form is already used in many places.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
gcc 4.8.2 reports this warning when extra warnings are enabled (-Wextra):
CC qga/commands.o
qga/commands.c: In function ‘slog’:
qga/commands.c:28:5: error:
function might be possible candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format]
g_logv("syslog", G_LOG_LEVEL_INFO, fmt, ap);
^
gcc 4.8.2 reports this warning when slog is declared with the
gnu_printf format attribute:
qga/commands-posix.c: In function ‘qmp_guest_file_open’:
qga/commands-posix.c:404:5: warning:
format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘int64_t’ [-Wformat=]
slog("guest-file-open, handle: %d", handle);
^
On 32 bit hosts there are three more warnings which are also fixed here.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
For now guest agent uses following command to shutdown system:
shutdown -P +0 "blabla"
but this syntax works only with shutdown command from systemd or upstart,
because SysV shutdown requires -h switch.
Following patch changes the command so it works with systemd, upstart and SysV
With upstart/systemd qga use one of thee commands, depending on 'mode' parameter:
shutdown -P +0 "..."
shutdown -H +0 "..."
shutdown -r +0 "..."
SysV equivalents for these are:
shutdown -h -P +0 "..."
shutdown -h -H +0 "..."
shutdown -h -r +0 "..."
and these retain their meaning with upstart/systemd.
According to FreeBSD manpages, shutdown does not accept -P and -H options. Commands should be:
shutdown -p +0 "..."
shutdown -h +0 "..."
shutdown -r +0 "..."
shutdown in Solaris does not accept any of -hHpPr and does not accept time in "+0" format
Signed-off-by: Michael Avdienko <whitearchey@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Currently, fsfreeze-freeze may cause deadlock if a guest has loopback mounts
of image files in its disk; e.g.:
# mount | grep ^/
/dev/vda1 / type ext4 (rw,noatime,seclabel,data=ordered)
/tmp/disk.img on /mnt type ext4 (rw,relatime,seclabel)
To avoid the deadlock, this freezes filesystems in reverse order of mounts.
Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@hds.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
*fix up commit msg
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
In Windows guests this may make a difference.
Since the original patch (commit c689b4f1) sought to be pedantic and to
consider theoretical corner cases of portability, we should fix it up
where it failed to come through in that pursuit.
Suggested-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
The qemu guest agent creates a bunch of files with insecure permissions
when started in daemon mode. For example:
-rw-rw-rw- 1 root root /var/log/qemu-ga.log
-rw-rw-rw- 1 root root /var/run/qga.state
-rw-rw-rw- 1 root root /var/log/qga-fsfreeze-hook.log
In addition, at least all files created with the "guest-file-open" QMP
command, and all files created with shell output redirection (or
otherwise) by utilities invoked by the fsfreeze hook script are affected.
For now mask all file mode bits for "group" and "others" in
become_daemon().
Temporarily, for compatibility reasons, stick with the 0666 file-mode in
case of files newly created by the "guest-file-open" QMP call. Do so
without changing the umask temporarily.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Fix various typos and misspellings. The bulk of these were found with
codespell.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
*added stub for w32
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
*added stub for w32
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Hosts hold on to handles provided by guest-file-open for periods that can
span beyond the life of the qemu-ga process that issued them. Since these
are issued starting from 0 on every restart, we run the risk of issuing
duplicate handles after restarts/reboots.
As a result, users with a stale copy of these handles may end up
reading/writing corrupted data due to their existing handles effectively
being re-assigned to an unexpected file or offset.
We unfortunately do not issue handles as strings, but as integers, so a
solution such as using UUIDs can't be implemented without introducing a
new interface.
As a workaround, we fix this by implementing a persistent key-value store
that will be used to track the value of the last handle that was issued
across restarts/reboots to avoid issuing duplicates.
The store is automatically written to the same directory we currently
set via --statedir to track fsfreeze state, and so should be applicable
for stable releases where this flag is supported.
A follow-up can use this same store for handling fsfreeze state, but
that change is cosmetic and left out for now.
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Cc: qemu-stable@nongnu.org
* fixed guest_file_handle_add() return value from uint64_t to int64_t
Spotted by Coverity.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Neglects to free errors allocated by qmp_guest_fsfreeze_thaw().
Spotted by Coverity.
While there, drop the test whether return value is negative (it's
never true), and improve logging.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
g_strdup_printf already handles OOM errors, so some error handling in
QEMU code can be removed.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
To use the online disk snapshot for online-backup, application-level
consistency of the snapshot image is required. However, currently the
guest agent can provide only filesystem-level consistency, and the
snapshot may contain dirty data, for example, incomplete transactions.
This patch provides the opportunity to quiesce applications before
snapshot is taken.
If --fsfreeze-hook option is specified, the hook is executed with
"freeze" argument before the filesystem is frozen by fsfreeze-freeze
command. As for fsfreeze-thaw command, the hook is executed with "thaw"
argument after the filesystem is thawed.
This patch depends on patchset to improve error reporting by Luiz Capitulino:
http://lists.gnu.org/archive/html/qemu-devel/2012-11/msg03016.html
Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
*clarified usage in help output
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Most errors are QERR_UNDEFINED_ERROR today.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Most errors are QERR_UNDEFINED_ERROR today.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Convert them to error_setg_errno().
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Convert them to error_setg_errno().
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Convert them to error_setg_errno().
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Most errors are QERR_UNDEFINED_ERROR. Also, adds ga_wait_child() as
a future commit will use it too.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Use error_setg_errno() when possible with an improved error description.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
*Fixed missing space character in error message
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
* 'trivial-patches' of git://github.com/stefanha/qemu:
versatilepb: Use symbolic indices for ARM PIC
qdev: kill bogus comment
qemu-barrier: Fix compiler version check for future gcc versions
hw: Add missing 'static' attribute for QEMUMachine
cleanup useless return sentence
qemu-sockets: Fix compiler warning (regression for MinGW)
vnc: Fix spelling (hellmen -> hellman) in comment
slirp: Fix spelling in comment (enought -> enough, insure -> ensure)
tcg/arm: Use tcg_out_mov_reg rather than inline equivalent code
cpu: Add missing 'static' attribute to qemu_global_mutex
configure: Support empty target list (--target-list=)
hw: Fix return value check for bdrv_read, bdrv_write
This patch cleans up return sentences in the end of void functions.
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Amos Kong <akong@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
NUL-termination of the .ifr_name field is not required, but is fine
(and preferable to using strncpy and leaving the reader to wonder),
since the first thing the linux kernel does is to clear the last byte.
Besides, using pstrcpy here makes this setting of ifr_name consistent
with the other code (e.g., net/tap-linux.c) that does the same thing.
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
FITRIM is a mounted filesystem feature to discard (or "trim") blocks which
are not in use by the filesystem. This is useful for solid-state drives
(SSDs) and thinly-provisioned storage. Provide access to the feature
from the host so that filesystems can be trimmed periodically or before
migration.
Here is an example using scsi_debug:
# modprobe scsi_debug lbpu=1 lbpws=1
# sg_vpd -p0xb2 /dev/sdb
Logical block provisioning VPD page (SBC):
Unmap command supported (LBPU): 1
Write same (16) with unmap bit supported (LBWS): 1
Write same (10) with unmap bit supported (LBWS10): 0
# mke2fs /dev/sdb
# cat /sys/bus/pseudo/drivers/scsi_debug/map
1-616,16257-16383
# mount /dev/sdb /run/media/pbonzini/test
# dd if=/dev/zero of=/run/media/pbonzini/test/file
# cat map
1-616,645-1588,1599-4026,4029-16383
# rm /run/media/pbonzini/test/file
# ./qemu-ga /dev/fd/0
{"execute":"guest-fstrim"}
{"return": {}}
# cat map
1-612
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
We will use these functions and types for more than FSFREEZE, so rename them.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Currently we re-read/re-process /etc/mtab to get an updated list of
mounts when guest-fsfreeze-thaw is called. This can cause an atime
update on /etc/mtab, which will block if we're in a frozen state.
Instead, use /proc's version of mtab, which may not be up-to-date with
options passed via -o remount, but is compatible for our use cases since
we only care about the filesystem type.
Reported-by: Matsuda, Daiki <matsudadik@intellilink.co.jp>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Use _NSGetEnviron() helper to access the environment.
Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Cc: Charlie Somerville <charlie@charliesomerville.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Commit 3674838cd0 uses the environ global
variable, but is relying on environ to be declared somewhere else.
This worked for me because on F16 environ is declared in <unistd.h>, but
that doesn't happen in OpenBSD for example, causing a build failure.
This commit fixes the build error by declaring environ if it hasn't
being declared yet.
Also fixes a build warning due to a missing <sys/wait.h> include.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
POSIX mandates[1] that a child process of a multi-thread program uses
only async-signal-safe functions before exec(). We consider qemu-ga
to be multi-thread, because it uses glib.
However, qmp_guest_shutdown() uses functions that are not
async-signal-safe. Fix it the following way:
- fclose() -> reopen_fd_to_null()
- execl() -> execle()
- exit() -> _exit()
- drop slog() usage (which is not safe)
[1] http://pubs.opengroup.org/onlinepubs/009695399/functions/fork.html
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Last commit dropped qemu-ga's SIGCHLD handler, used to automatically
reap terminated children processes. This introduced a bug to
qmp_guest_shutdown(): it will generate zombies.
This problem probably doesn't matter in the success case, as the VM
will shutdown anyway, but let's do the right thing and reap the
created process. This ultimately means that guest-shutdown is now a
synchronous command.
An interesting side effect is that guest-shutdown is now able to
report an error to the client if shutting down fails.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Currently, qemu-ga has a SIGCHLD handler that automatically reaps terminated
children processes. The idea is to avoid having qemu-ga commands blocked
waiting for children to terminate.
That approach has two problems:
1. qemu-ga is unable to detect errors in the child, meaning that qemu-ga
returns success even if the child fails to perform its task
2. if a command does depend on the child exit status, the command has to
play tricks to bypass the automatic reaper
Case 2 impacts the guest-suspend-* API, because it has to execute an external
program to check for suspend support. Today, to bypass the automatic reaper,
suspend code has to double fork and pass exit status information through a
pipe. Besides being complex, this is prone to race condition bugs. Indeed,
the current code does have such bugs.
Making the guest-suspend-* API synchronous (ie. by dropping the SIGCHLD
handler and calling waitpid() from commands) is a much simpler approach,
which fixes current race conditions bugs and enables commands to detect
errors in the child.
This commit does just that. There's a side effect though, guest-shutdown
will generate zombies if shutting down fails. This will be fixed by the
next commit.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
The next commit wants to use it.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
These were identified using: http://github.com/lyda/misspell-check
and run like this to create a bourne shell script using GNU sed's
-i option:
git ls-files|grep -vF .bin | misspellings -f - |grep -v '^ERROR:' |perl \
-pe 's/^(.*?)\[(\d+)\]: (\w+) -> "(.*?)"$/sed -i '\''${2}s!$3!$4!'\'' $1/'
Manually eliding the FP, "rela->real" and resolving "addres" to
address (not "adders") we get this:
sed -i '450s!thru!through!' Changelog
sed -i '260s!neccessary!necessary!' coroutine-sigaltstack.c
sed -i '54s!miniscule!minuscule!' disas.c
sed -i '1094s!thru!through!' hw/usb/hcd-ehci.c
sed -i '1095s!thru!through!' hw/usb/hcd-ehci.c
sed -i '21s!unecessary!unnecessary!' qapi-schema-guest.json
sed -i '307s!explictly!explicitly!' qemu-ga.c
sed -i '490s!preceeding!preceding!' qga/commands-posix.c
sed -i '792s!addres!address!' qga/commands-posix.c
sed -i '6s!beeing!being!' tests/tcg/test-mmap.c
Also, manually fix "arithmentic", spotted by Peter Maydell:
sed -i 's!arithmentic!arithmetic!' coroutine-sigaltstack.c
Signed-off-by: Jim Meyering <meyering@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Currently we rely on fsfreeze/thaw commands disabling/enabling logging
then having other commands check whether logging is disabled to avoid
executing if they aren't safe for running while a filesystem is frozen.
Instead, have an explicit whitelist of fsfreeze-safe commands, and
consolidate logging and command enablement/disablement into a pair
of helper functions: ga_set_frozen()/ga_unset_frozen()
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
