These days, many programs are including a bug-reporting address,
or better yet, a link to the project web site, at the tail of
their --help output. However, we were not very consistent at
doing so: only qemu-nbd and qemu-qa mentioned anything, with the
latter pointing to an individual person instead of the project.
Add a new #define that sets up a uniform string, mentioning both
bug reporting instructions and overall project details, and which
a downstream vendor could tweak if they want bugs to go to a
downstream database. Then use it in all of our binaries which
have --help output.
The canned text intentionally references http:// instead of https://
because our https website currently causes certificate errors in
some browsers. That can be tweaked later once we have resolved the
web site issued.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20170803163353.19558-5-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Include the package version information (useful for detecting
builds from git or downstream backports), and the copyright notice.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20170803163353.19558-3-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now that qcow & qcow2 are wired up to get encryption keys
via the QCryptoSecret object, nothing is relying on the
interactive prompting for passwords. All the code related
to password prompting can thus be ripped out.
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170623162419.26068-17-berrange@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Most callback commands in qemu-io return 0 to keep the interpreter
loop running, or 1 to quit immediately. However, open_f() just
passed through the return value of openfile(), which has different
semantics of returning 0 if a file was opened, or 1 on any failure.
As a result of mixing the return semantics, we are forcing the
qemu-io interpreter to exit early on any failures, which is rather
annoying when some of the failures are obviously trying to give
the user a hint of how to proceed (if we didn't then kill qemu-io
out from under the user's feet):
$ qemu-io
qemu-io> open foo
qemu-io> open foo
file open already, try 'help close'
$ echo $?
0
In general, we WANT openfile() to report failures, since it is the
function used in the form 'qemu-io -c "$something" no_such_file'
for performing one or more -c options on a single file, and it is
not worth attempting $something if the file itself cannot be opened.
So the solution is to fix open_f() to always return 0 (when we are
in interactive mode, even failure to open should not end the
session), and save the return value of openfile() for command line
use in main().
Note, however, that we do have some qemu-iotests that do 'qemu-io
-c "open file" -c "$something"'; such tests will now proceed to
attempt $something whether or not the open succeeded, the same way
as if the two commands had been attempted in interactive mode. As
such, the expected output for those tests has to be modified. But it
also means that it is now possible to use -c close and have a single
qemu-io command line operate on more than one file even without
using interactive mode. Although the '-c open' action is a subtle
change in behavior, remember that qemu-io is for debugging purposes,
so as long as it serves the needs of qemu-iotests while still being
reasonable for interactive use, it should not be a problem that we
are changing tests to the new behavior.
This has been awkward since at least as far back as commit
e3aff4f, in 2009.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Fam's addition of --force-share in commits 459571f7 and 335e9937
were developed prior to the addition of QDict scalar insertion
macros, but merged after the general cleanup in commit 46f5ac20.
Patch created mechanically by rerunning:
spatch --sp-file scripts/coccinelle/qobject.cocci \
--macro-file scripts/cocci-macro-file.h --dir . --in-place
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170515195439.17677-1-eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Add --force-share/-U to program options and -U to open subcommand.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We now have macros in place to make it less verbose to add a scalar
to QDict and QList, so use them.
Patch created mechanically via:
spatch --sp-file scripts/coccinelle/qobject.cocci \
--macro-file scripts/cocci-macro-file.h --dir . --in-place
then touched up manually to fix a couple of '?:' back to original
spacing, as well as avoiding a long line in monitor.c.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20170427215821.19397-7-eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The result of openfile was not checked, leading to failure deep in the
actual command with confusing error message, and exiting with exit code 0.
Here is a simple example - trying to read with the wrong format:
$ touch file
$ qemu-io -f qcow2 -c 'read -P 1 0 1024' file; echo $?
can't open device file: Image is not in qcow2 format
no file open, try 'help open'
0
With this patch, we fail earlier with exit code 1:
$ ./qemu-io -f qcow2 -c 'read -P 1 0 1024' file; echo $?
can't open device file: Image is not in qcow2 format
1
Failing earlier, we don't log this error now:
no file open, try 'help open'
But some tests expected it; the line was removed from the test output.
Signed-off-by: Nir Soffer <nirsof@gmail.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20170201003120.23378-2-nirsof@gmail.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Remove the notion of there being a single global array
of trace events, by introducing a method for registering
groups of events.
The module_call_init() needs to be invoked at the start
of any program that wants to make use of the trace
support. Currently this covers system emulators qemu-nbd,
qemu-img and qemu-io.
[Squashed the following fix from Daniel P. Berrange
<berrange@redhat.com>:
linux-user/bsd-user: initialize trace events subsystem
The bsd-user/linux-user programs make use of the CPU emulation
code and this now requires that the trace events subsystem
is enabled, otherwise it'll crash trying to allocate an empty
trace events bitmap for the CPU object.
--Stefan]
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-14-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Moving trace_init_backends() into trace_opt_parse() is not possible. This
should be called after daemonize() in vl.c.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1466174654-30130-5-git-send-email-den@openvz.org
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
In addition to making the code simpler, this will replace the
long error messages:
cannot initialize crypto: Unable to initialize GNUTLS library: [...]
cannot initialize crypto: Unable to initialize gcrypt
with shorter messages:
Unable to initialize GNUTLS library: [...]
Unable to initialize gcrypt
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
The command line defaults to BDRV_O_UNMAP, but can use
-d to reset it. Meanwhile, the 'open' subcommand was
defaulting to no discards, with no way to set it.
The command line has both -n and -tMODE to set a variety
of cache modes, but the 'open' subcommand had only -n.
The 'open' subcommand had no way to set BDRV_O_NATIVE_AIO.
Note that the 'reopen' subcommand uses '-c' where the
command line and 'open' use -t. Making that consistent
would be a separate patch.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 1462677405-4752-3-git-send-email-eblake@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
The Usage: summary is missing several options, but rather than
having to maintain it, it's simpler to just state [OPTIONS],
since the options are spelled out below.
Commit 499afa2 added --image-opts, but forgot to document it in
--help. Likewise for commit 9e8f183 and -d/--discard.
Commit e3aff4f6 put "-o/--offset" in the long opts, but it has
never been honored.
Add a note that '-n' is short for '-t none'.
Commit 9a2d77ad killed the -C option, but forgot to undocument
it for the 'open' subcommand.
Finally, commit 10d9d75 removed -g/--growable, but forgot to
cull it from the valid short options.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 1462677405-4752-2-git-send-email-eblake@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
qemu_opts_foreach() runs its callback with the error location set to
the option's location. Any errors the callback reports use the
option's location automatically.
Commit 90998d5 moved the actual error reporting from "inside"
qemu_opts_foreach() to after it. Here's a typical hunk:
if (qemu_opts_foreach(qemu_find_opts("object"),
- object_create,
- object_create_initial, NULL)) {
+ user_creatable_add_opts_foreach,
+ object_create_initial, &err)) {
+ error_report_err(err);
exit(1);
}
Before, object_create() reports from within qemu_opts_foreach(), using
the option's location. Afterwards, we do it after
qemu_opts_foreach(), using whatever location happens to be current
there. Commonly a "none" location.
This is because Error objects don't have location information.
Problematic.
Reproducer:
$ qemu-system-x86_64 -nodefaults -display none -object secret,id=foo,foo=bar
qemu-system-x86_64: Property '.foo' not found
Note no location. This commit restores it:
qemu-system-x86_64: -object secret,id=foo,foo=bar: Property '.foo' not found
Note that the qemu_opts_foreach() bug just fixed could mask the bug
here: if the location it leaves dangling hasn't been clobbered, yet,
it's the correct one.
Reported-by: Eric Blake <eblake@redhat.com>
Cc: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1461767349-15329-4-git-send-email-armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Paragraph on Error added to commit message]
Any programs which call the qcrypto APIs should ensure that
qcrypto_init() has been called before anything else which
can use crypto. Essentially this means right at the start
of the main method before initializing anything else.
This is important because some versions of gnutls/gcrypt
require explicit initialization before use.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Alex Bligh <alex@alex.org.uk>
Tested-by: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The qemu-img/qemu-io tools prompt for disk encryption passwords
regardless of whether any are actually required. Adding a check
on bdrv_key_required() avoids this prompt for disk formats which
have been converted to the QCryptoSecret APIs.
This is just a temporary hack to ensure the block I/O tests
continue to work after each patch, since the last patch will
completely delete all the password prompting code.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef. Since then, we've moved to include qemu/osdep.h
everywhere. Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h. That's in excess of
100KiB of crap most .c files don't actually need.
Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h. Include qapi/error.h in .c files that need it and don't
get it now. Include qapi-types.h in qom/object.h for uint16List.
Update scripts/clean-includes accordingly. Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h
comment quoted above similarly.
This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third. Unfortunately, the number depending on
qapi-types.h shrinks only a little. More work is needed for that one.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Before this patch, blk_new() automatically assigned a name to the new
BlockBackend and considered it referenced by the monitor. This patch
removes the implicit monitor_add_blk() call from blk_new() (and
consequently the monitor_remove_blk() call from blk_delete(), too) and
thus blk_new() (and related functions) no longer take a BB name
argument.
In fact, there is only a single point where blk_new()/blk_new_open() is
called and the new BB is monitor-owned, and that is in blockdev_init().
Besides thus relieving us from having to invent names for all of the BBs
we use in qemu-img, this fixes a bug where qemu cannot create a new
image if there already is a monitor-owned BB named "image".
If a BB and its BDS tree are created in a single operation, as of this
patch the BDS tree will be created before the BB is given a name
(whereas it was the other way around before). This results in minor
change to the output of iotest 087, whose reference output is amended
accordingly.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When declaring the 'struct option' array, use the standard
constants no_argument/required_argument, instead of magic
values 0 and 1.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently qemu-io allows an image filename to be passed on the
command line, but unless using the JSON format, it does not have
a way to set any options except the format eg
qemu-io https://127.0.0.1/images/centos7.iso
qemu-io /home/berrange/demo.qcow2
By contrast when using the interactive shell, it is possible to
use --option with the 'open' command, or to omit the filename.
This adds a --image-opts arg that indicates that the positional
filename should be interpreted as a full option string, not
just a filename.
qemu-io --image-opts driver=https,url=https://127.0.0.1/images,sslverify=off
qemu-io --image-opts driver=qcow2,file.filename=/home/berrange/demo.qcow2
This flag is mutually exclusive with the '-f' flag and with
the '-o' flag to the 'open' command
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Allow creation of user creatable object types with qemu-io
via a new --object command line arg. This will be used to supply
passwords and/or encryption keys to the various block driver
backends via the recently added 'secret' object type.
# printf letmein > mypasswd.txt
# qemu-io --object secret,id=sec0,file=mypasswd.txt \
...other args...
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This converts the NBD block driver client to use the QIOChannelSocket
class for initial connection setup. The NbdClientSession struct has
two pointers, one to the master QIOChannelSocket providing the raw
data channel, and one to a QIOChannel which is the current channel
used for I/O. Initially the two point to the same object, but when
TLS support is added, they will point to different objects.
The qemu-img & qemu-io tools now need to use MODULE_INIT_QOM to
ensure the QIOChannel object classes are registered. The qemu-nbd
tool already did this.
In this initial conversion though, all I/O is still actually done
using the raw POSIX sockets APIs.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-4-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is cleaner, and improves error reporting with -daemonize.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-id: 1452174932-28657-4-git-send-email-den@openvz.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is cleaner and has two advantages. First, it improves error
reporting with -daemonize. Second, multiple "-trace events" options
now cumulate.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-id: 1452174932-28657-3-git-send-email-den@openvz.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Just three instances left.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1450452927-8346-16-git-send-email-armbru@redhat.com>
qemu_opts_parse_noisily() already prints an error message with the exact
reason why the parsing failed. No need to add another less specific one.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
qerror_report_err() is a transitional interface to help with
converting existing monitor commands to QMP. It should not be used
elsewhere.
The only remaining user in qemu-option.c is qemu_opts_parse(). Is it
used in QMP context? If not, we can simply replace
qerror_report_err() by error_report_err().
The uses in qemu-img.c, qemu-io.c, qemu-nbd.c and under tests/ are
clearly not in QMP context.
The uses in vl.c aren't either, because the only QMP command handlers
there are qmp_query_status() and qmp_query_machines(), and they don't
call it.
Remaining uses:
* drive_def(): Command line -drive and such, HMP drive_add and pci_add
* hmp_chardev_add(): HMP chardev-add
* monitor_parse_command(): HMP core
* tmp_config_parse(): Command line -tpmdev
* net_host_device_add(): HMP host_net_add
* net_client_parse(): Command line -net and -netdev
* qemu_global_option(): Command line -global
* vnc_parse_func(): Command line -display, -vnc, default display, HMP
change, QMP change. Bummer.
* qemu_pci_hot_add_nic(): HMP pci_add
* usb_net_init(): Command line -usbdevice, HMP usb_add
Propagate errors through qemu_opts_parse(). Create a convenience
function qemu_opts_parse_noisily() that passes errors to
error_report_err(). Switch all non-QMP users outside tests to it.
That leaves vnc_parse_func(). Propagate errors through it. Since I'm
touching it anyway, rename it to vnc_parse().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
The qemu-io tool does not check if the image is encrypted so
historically would silently corrupt the sectors by writing
plain text data into them instead of cipher text. The earlier
commit turns this mistake into a fatal abort, so check for
encryption and prompt for key when required.
This enables us to add unit tests to ensure we don't break
the ability of qemu-img to convert existing encrypted qcow2
files into a non-encrypted format.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
POSIX says getopt() returns -1 on completion. While Linux happens
to define EOF as -1, this definition is not required by POSIX, and
there may be platforms where checking for EOF instead of -1 would
lead to an infinite loop.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
qemu-io should behave like a guest, therefore it should use BlockBackend
to access the block layer.
There are a couple of places where that is infeasible: First, the
bdrv_debug_* functions could theoretically be mirrored in the
BlockBackend, but since these are functions internal to the block layer,
they should not be visible externally (qemu-io as a test tool is exempt
from this).
Second, bdrv_get_info() and bdrv_get_specific_info() work on a single
BDS alone, therefore they should stay BDS-specific.
Third, bdrv_is_allocated() mainly works on a single BDS as well. Some
data may be passed through from the BDS's file (if sectors which are
apparently allocated in the file are not really allocated there but just
zero).
[Fixed conflicts around block_acct_start() usage from Fam Zheng's
"qemu-io: Account IO by aio_read and aio_write" commit. Use
BlockBackend and blk_get_stats() instead of BlockDriverState.
--Stefan]
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1423162705-32065-14-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Remove "growable" option from the "open" command and from the qemu-io
command line. qemu-io is about to be converted to BlockBackend which
will make sure that no request exceeds the image size, so the only way
to keep "growable" would be to use BlockBackend if it is not given and
to directly access the BDS if it is.
qemu-io is a debugging tool, therefore removing a rarely used option
will have only a very small impact, if any. There was only one
qemu-iotest which used the option; since it is not critical, this patch
just removes it.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1423162705-32065-13-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This adds a -f option to qemu-io which allows to explicitly specify the
block driver to use for the given image.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1416497234-29880-2-git-send-email-kwolf@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
On BlockBackend destruction, unref its BlockDriverState. Replaces the
callers' unrefs.
This turns the pointer from BlockBackend to BlockDriverState into a
strong reference, managed with bdrv_ref() / bdrv_unref(). The
back-pointer remains weak.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Convenience function blk_new_with_bs() creates a BlockBackend with its
BlockDriverState. Callers have to unref both. The commit after next
will relieve them of the need to unref the BlockDriverState.
Complication: due to the silly way drive_del works, we need a way to
hide a BlockBackend, just like bdrv_make_anon(). To emphasize its
"special" status, give the function a suitably off-putting name:
blk_hide_on_behalf_of_do_drive_del(). Unfortunately, hiding turns the
BlockBackend's name into the empty string. Can't avoid that without
breaking the blk->bs->device_name equals blk->name invariant.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
A block device consists of a frontend device model and a backend.
A block backend has a tree of block drivers doing the actual work.
The tree is managed by the block layer.
We currently use a single abstraction BlockDriverState both for tree
nodes and the backend as a whole. Drawbacks:
* Its API includes both stuff that makes sense only at the block
backend level (root of the tree) and stuff that's only for use
within the block layer. This makes the API bigger and more complex
than necessary. Moreover, it's not obvious which interfaces are
meant for device models, and which really aren't.
* Since device models keep a reference to their backend, the backend
object can't just be destroyed. But for media change, we need to
replace the tree. Our solution is to make the BlockDriverState
generic, with actual driver state in a separate object, pointed to
by member opaque. That lets us replace the tree by deinitializing
and reinitializing its root. This special need of the root makes
the data structure awkward everywhere in the tree.
The general plan is to separate the APIs into "block backend", for use
by device models, monitor and whatever other code dealing with block
backends, and "block driver", for use by the block layer and whatever
other code (if any) dealing with trees and tree nodes.
Code dealing with block backends, device models in particular, should
become completely oblivious of BlockDriverState. This should let us
clean up both APIs, and the tree data structures.
This commit is a first step. It creates a minimal "block backend"
API: type BlockBackend and functions to create, destroy and find them.
BlockBackend objects are created and destroyed exactly when root
BlockDriverState objects are created and destroyed. "Root" in the
sense of "in bdrv_states". They're not yet used for anything; that'll
come shortly.
A root BlockDriverState is created with bdrv_new_root(), so where to
create a BlockBackend is obvious. Where these roots get destroyed
isn't always as obvious.
It is obvious in qemu-img.c, qemu-io.c and qemu-nbd.c, and in error
paths of blockdev_init(), blk_connect(). That leaves destruction of
objects successfully created by blockdev_init() and blk_connect().
blockdev_init() is used only by drive_new() and qmp_blockdev_add().
Objects created by the latter are currently indestructible (see commit
48f364d "blockdev: Refuse to drive_del something added with
blockdev-add" and commit 2d246f0 "blockdev: Introduce
DriveInfo.enable_auto_del"). Objects created by the former get
destroyed by drive_del().
Objects created by blk_connect() get destroyed by blk_disconnect().
BlockBackend is reference-counted. Its reference count never exceeds
one so far, but that's going to change.
In drive_del(), the BB's reference count is surely one now. The BDS's
reference count is greater than one when something else is holding a
reference, such as a block job. In this case, the BB is destroyed
right away, but the BDS lives on until all extra references get
dropped.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Creating an anonymous BDS can't fail. Make that obvious.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
On a system with a low limit of open files the initialization
of the event notifier could fail and QEMU exits without printing any
error information to the user.
The problem can be easily reproduced by enforcing a low limit of open
files and start QEMU with enough I/O threads to hit this limit.
The same problem raises, without the creation of I/O threads, while
QEMU initializes the main event loop by enforcing an even lower limit of
open files.
This commit adds an error message on failure:
# qemu [...] -object iothread,id=iothread0 -object iothread,id=iothread1
qemu: Failed to initialize event notifier: Too many open files in system
Signed-off-by: Chrysostomos Nanakos <cnanakos@grnet.gr>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Commit 6db9560 split off the growable case so it can use
bdrv_file_open() instead of bdrv_open() then. Growable BDSes become
anonymous. Weird.
Commit 2e40134 folded bdrv_file_open() back into bdrv_open() with new
flag BDRV_O_PROTOCOL. We still have two bdrv_open() calls, and
growable BDSes remain anonymous.
Circle back to before commit 6db9560: just one call, not anonymous.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer,
for two reasons. One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.
Patch created with Coccinelle, with two manual changes on top:
* Add const to bdrv_iterate_format() to keep the types straight
* Convert the allocation in bdrv_drop_intermediate(), which Coccinelle
inexplicably misses
Coccinelle semantic patch:
@@
type T;
@@
-g_malloc(sizeof(T))
+g_new(T, 1)
@@
type T;
@@
-g_try_malloc(sizeof(T))
+g_try_new(T, 1)
@@
type T;
@@
-g_malloc0(sizeof(T))
+g_new0(T, 1)
@@
type T;
@@
-g_try_malloc0(sizeof(T))
+g_try_new0(T, 1)
@@
type T;
expression n;
@@
-g_malloc(sizeof(T) * (n))
+g_new(T, n)
@@
type T;
expression n;
@@
-g_try_malloc(sizeof(T) * (n))
+g_try_new(T, n)
@@
type T;
expression n;
@@
-g_malloc0(sizeof(T) * (n))
+g_new0(T, n)
@@
type T;
expression n;
@@
-g_try_malloc0(sizeof(T) * (n))
+g_try_new0(T, n)
@@
type T;
expression p, n;
@@
-g_realloc(p, sizeof(T) * (n))
+g_renew(T, p, n)
@@
type T;
expression p, n;
@@
-g_try_realloc(p, sizeof(T) * (n))
+g_try_renew(T, p, n)
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Adds support to compile QEMU with multiple tracing backends at the same time.
For example, you can compile QEMU with:
$ ./configure --enable-trace-backends=ftrace,dtrace
Where 'ftrace' can be handy for having an in-flight record of events, and 'dtrace' can be later used to extract more information from the system.
This patch allows having both available without recompiling QEMU.
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Instead of ignoring all option values but the last one, multiple -o
options now have the same meaning as having a single option with all
settings in the order of their respective -o options.
Same as commit 2dc8328 for qemu-img convert, except here we do it with
QemuOpts rather than QEMUOptionParameter.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch adds an errp parameter to bdrv_new() and updates all its
callers. The next patches will make use of this in order to check for
duplicate IDs. Most of the callers know that their ID is fine, so they
can simply assert that there is no error.
Behaviour doesn't change with this patch yet as bdrv_new() doesn't
actually assign errors to errp.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Eric Blake