qemu-ga: avoid blocking on atime update when reading /etc/mtab

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

qemu-ga: avoid blocking on atime update when reading /etc/mtab

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>

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qemu-ga: Fix use of environ on Darwin

Use _NSGetEnviron() helper to access the environment.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Cc: Charlie Somerville <charlie@charliesomerville.

qemu-ga: Fix use of environ on Darwin

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>

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qemu-ga: Fix missing environ declaration

Commit 3674838cd05268954bb6473239cd7f700a79bf0f uses the environ global
variable, but is relying on environ to be declared somewhere else.

This worked for m

qemu-ga: Fix missing environ declaration

Commit 3674838cd05268954bb6473239cd7f700a79bf0f 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>

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qemu-ga: align versioning with QEMU_VERSION

Previously qemu-ga version was defined seperately. Since it is aligned
with QEMU releases, use QEMU_VERSION instead. This also implies the
version bump fo

qemu-ga: align versioning with QEMU_VERSION

Previously qemu-ga version was defined seperately. Since it is aligned
with QEMU releases, use QEMU_VERSION instead. This also implies the
version bump for 1.1[-rcN] release of qemu-ga.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Acked-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

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qemu-ga: guest-shutdown: use only async-signal-safe functions

POSIX mandates[1] that a child process of a multi-thread program uses
only async-signal-safe functions before exec(). We consider qemu-g

qemu-ga: guest-shutdown: use only async-signal-safe functions

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>

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qemu-ga: guest-shutdown: become synchronous

Last commit dropped qemu-ga's SIGCHLD handler, used to automatically
reap terminated children processes. This introduced a bug to
qmp_guest_shutdown(): it

qemu-ga: guest-shutdown: become synchronous

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>

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qemu-ga: guest-suspend: make the API synchronous

Currently, qemu-ga has a SIGCHLD handler that automatically reaps terminated
children processes. The idea is to avoid having qemu-ga commands blocked

qemu-ga: guest-suspend: make the API synchronous

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>

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qemu-ga: make reopen_fd_to_null() public

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

qemu-ga: make reopen_fd_to_null() public

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>

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fix some common typos

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 | mi

fix some common typos

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>

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Merge remote-tracking branch 'mdroth/qga-pull-4-27-12' into staging

* mdroth/qga-pull-4-27-12:
qemu-ga: persist tracking of fsfreeze state via filesystem
qemu-ga: add a whitelist for fsfreeze-sa

Merge remote-tracking branch 'mdroth/qga-pull-4-27-12' into staging

* mdroth/qga-pull-4-27-12:
qemu-ga: persist tracking of fsfreeze state via filesystem
qemu-ga: add a whitelist for fsfreeze-safe commands
qemu-ga: improve recovery options for fsfreeze

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qemu-ga: Implement alternative to O_ASYNC

ga_channel_open() was using open flag O_ASYNC for SIGIO-driven I/O.
This breaks on illumos, so fall back to POSIX I_SETSIG ioctl (SIGPOLL).

Signed-off-by:

qemu-ga: Implement alternative to O_ASYNC

ga_channel_open() was using open flag O_ASYNC for SIGIO-driven I/O.
This breaks on illumos, so fall back to POSIX I_SETSIG ioctl (SIGPOLL).

Signed-off-by: Lee Essen <lee.essen@nowonline.co.uk>
Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>

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qemu-ga: add a whitelist for fsfreeze-safe commands

Currently we rely on fsfreeze/thaw commands disabling/enabling logging
then having other commands check whether logging is disabled to avoid
execu

qemu-ga: add a whitelist for fsfreeze-safe commands

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>

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qemu-ga: improve recovery options for fsfreeze

guest-fsfreeze-thaw relies on state information obtained from
guest-fsfreeze-freeze to determine what filesystems to unfreeze.
This is unreliable due t

qemu-ga: improve recovery options for fsfreeze

guest-fsfreeze-thaw relies on state information obtained from
guest-fsfreeze-freeze to determine what filesystems to unfreeze.
This is unreliable due to the fact that that state does not account
for FIFREEZE being issued by other processes, or previous instances
of qemu-ga. This means in certain situations we cannot thaw
filesystems even with a responsive qemu-ga instance at our disposal.

This patch allows guest-fsfreeze-thaw to be issued unconditionally.
It also adds some additional logic to allow us to thaw filesystems
regardless of how many times the filesystem's "frozen" refcount has
been incremented by any guest processes.

Also, guest-fsfreeze-freeze now operates atomically: on success all
freezable filesystems are frozen, and on error all filesystems are
thawed. The ambiguous "GUEST_FSFREEZE_STATUS_ERROR" state is no
longer entered.

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

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qemu-ga: generate missing stubs for fsfreeze

When linux-specific commands (including guest-fsfreeze-*) were consolidated
under defined(__linux__), we forgot to account for the case where
defined(__l

qemu-ga: generate missing stubs for fsfreeze

When linux-specific commands (including guest-fsfreeze-*) were consolidated
under defined(__linux__), we forgot to account for the case where
defined(__linux__) && !defined(FIFREEZE). As a result stubs are no longer
being generated on linux hosts that don't have FIFREEZE support. Fix
this.

Tested-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>

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qemu-ga: fix bsd build, and re-org linux-specific implementations

qemu-ga: for w32, fix leaked handle ov.hEvent in ga_channel_write()

In the function ga_channel_write(), the handle ov.hEvent is created
by the call to CreateEvent(). However, the handle is not close

qemu-ga: for w32, fix leaked handle ov.hEvent in ga_channel_write()

In the function ga_channel_write(), the handle ov.hEvent is created
by the call to CreateEvent(). However, the handle is not closed
prior to the function return.

This patch closes the handle before the return of the function.

Kudos to Paolo Bonzini for spotting this bug.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Acked-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

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qemu-ga: add guest-sync-delimited

guest-sync leaves it as an exercise to the user as to how to reliably
obtain the response to guest-sync if the client had previously read in a
partial response (due

qemu-ga: add guest-sync-delimited

guest-sync leaves it as an exercise to the user as to how to reliably
obtain the response to guest-sync if the client had previously read in a
partial response (due qemu-ga previously being restarted mid-"sentence"
due to reboot, forced restart, etc).

qemu-ga handles this situation on its end by having a client precede
their guest-sync request with a 0xFF byte (invalid UTF-8), which
qemu-ga/QEMU JSON parsers will treat as a flush event. Thus we can
reliably flush the qemu-ga parser state in preparation for receiving
the guest-sync request.

guest-sync-delimited provides the same functionality for a client: when
a guest-sync-delimited is issued, qemu-ga will precede it's response
with a 0xFF byte that the client can use as an indicator to flush its
buffer/parser state in preparation for reliably receiving the
guest-sync-delimited response.

It is also useful as an optimization for clients, since, after issuing a
guest-sync-delimited, clients can safely discard all stale data read
from the channel until the 0xFF is found.

More information available on the wiki:

http://wiki.qemu.org/Features/QAPI/GuestAgent#QEMU_Guest_Agent_Protocol

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

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qemu-ga: add guest-network-get-interfaces command

This command returns an array of:

[ifname, hwaddr, [ipaddr, ipaddr_family, prefix] ]

for each interface in the system.
Currently, only IPv4 and I

qemu-ga: add guest-network-get-interfaces command

This command returns an array of:

[ifname, hwaddr, [ipaddr, ipaddr_family, prefix] ]

for each interface in the system.
Currently, only IPv4 and IPv6 are supported.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

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qemu-ga: add win32 guest-suspend-ram command

S3 sleep implementation for windows.

qemu-ga: add win32 guest-suspend-disk command.

Implement guest-suspend-disk RPC for Windows. Functionally this should be
equivalent to the posix implementation.

Signed-off-by: Gal Hammer <ghammer@r

qemu-ga: add win32 guest-suspend-disk command.

Implement guest-suspend-disk RPC for Windows. Functionally this should be
equivalent to the posix implementation.

Signed-off-by: Gal Hammer <ghammer@redhat.com>

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qemu-ga: add guest-suspend-hybrid

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

qemu-ga: add guest-suspend-ram

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

qemu-ga: add guest-suspend-disk

As the command name implies, this command suspends the guest to disk.

The suspend operation is implemented by two functions: bios_supports_mode()
and guest_suspend()

qemu-ga: add guest-suspend-disk

As the command name implies, this command suspends the guest to disk.

The suspend operation is implemented by two functions: bios_supports_mode()
and guest_suspend(). Both functions are generic enough to be used by
other suspend modes (introduced by next commits).

Both functions will try to use the scripts provided by the pm-utils
package if it's available. If it's not available, a manual method,
which consists of directly writing to '/sys/power/state', will be used.

To reap terminated children, a new signal handler is installed in the
parent to catch SIGCHLD signals and a non-blocking call to waitpid()
is done to collect their exit statuses. The statuses, however, are
discarded.

The approach used to query the guest for suspend support deserves some
explanation. It's implemented by bios_supports_mode() and shown below:

qemu-ga
|
create pipe
|
fork()
-----------------
| |
| |
| fork()
| --------------------------
| | |
| | |
| | exec('pm-is-supported')
| |
| wait()
| write exit status to pipe
| exit
|
read pipe

This might look complex, but the resulting code is quite simple.
The purpose of that approach is to allow qemu-ga to reap its children
(semi-)automatically from its SIGCHLD handler.

Implementing this the obvious way, that's, doing the exec() call from
the first child process, would force us to introduce a more complex way
to reap qemu-ga's children. Like registering PIDs to be reaped and
having a way to wait for them when returning their exit status to
qemu-ga is necessary. The approach explained above avoids that complexity.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

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qemu-ga: add win32 guest-shutdown command

Implement guest-shutdown RPC for Windows. Functionally this should be
equivalent to the posix implementation.

Original patch by Gal Hammer <ghammer@redhat.

qemu-ga: add win32 guest-shutdown command

Implement guest-shutdown RPC for Windows. Functionally this should be
equivalent to the posix implementation.

Original patch by Gal Hammer <ghammer@redhat.com>

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qemu-ga: add Windows service integration

This allows qemu-ga to function as a Windows service:

- to install the service (will auto-start on boot):
qemu-ga --service install
- to start the se

qemu-ga: add Windows service integration

This allows qemu-ga to function as a Windows service:

- to install the service (will auto-start on boot):
qemu-ga --service install
- to start the service:
net start qemu-ga
- to stop the service:
net stop qemu-ga
- to uninstall service:
qemu-ga --service uninstall

Original patch by Gal Hammer <ghammer@redhat.com>

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