Commit Graph

118 Commits

Author SHA1 Message Date
Fam Zheng
ee7d7aabda nbd: Always call "close_fn" in nbd_client_new
Rename the parameter "close" to "close_fn" to disambiguous with
close(2).

This unifies error handling paths of NBDClient allocation:
nbd_client_new will shutdown the socket and call the "close_fn" callback
if negotiation failed, so the caller don't need a different path than
the normal close.

The returned pointer is never used, make it void in preparation for the
next patch.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1452760863-25350-2-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-15 18:58:01 +01:00
Markus Armbruster
433672b0d5 error: Clean up errors with embedded newlines (again)
The arguments of error_report() should yield a short error string
without newlines.

A few places try to print additional help after the error message by
embedding newlines in the error string.  That's nice, but let's do it
the right way.  Commit 474c213 cleaned up some, but they keep coming
back.  Offenders tracked down with the Coccinelle semantic patch from
commit 312fd5f.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-01-13 15:16:18 +01:00
Markus Armbruster
9af9e0fed7 error: Strip trailing '\n' from error string arguments (again)
Commit 6daf194d, be62a2eb and 312fd5f got rid of a bunch, but they
keep coming back.  Tracked down with the Coccinelle semantic patch
from commit 312fd5f.

Cc: Fam Zheng <famz@redhat.com>
Cc: Peter Crosthwaite <crosthwaitepeter@gmail.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Cc: Stefan Berger <stefanb@linux.vnet.ibm.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Changchun Ouyang <changchun.ouyang@intel.com>
Cc: zhanghailiang <zhang.zhanghailiang@huawei.com>
Cc: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Acked-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1450452927-8346-17-git-send-email-armbru@redhat.com>
2016-01-13 15:16:18 +01:00
Markus Armbruster
b988468149 qemu-io qemu-nbd: Use error_report() etc. instead of fprintf()
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>
2016-01-13 15:16:18 +01:00
Markus Armbruster
c29b77f955 error: Use error_reportf_err() where it makes obvious sense
Done with this Coccinelle semantic patch

    @@
    expression FMT, E, S;
    expression list ARGS;
    @@
    -    error_report(FMT, ARGS, error_get_pretty(E));
    +    error_reportf_err(E, FMT/*@@@*/, ARGS);
    (
    -    error_free(E);
    |
	 exit(S);
    |
	 abort();
    )

followed by a replace of '%s"/*@@@*/' by '"' and some line rewrapping,
because I can't figure out how to make Coccinelle transform strings.

We now use the error whole instead of just its message obtained with
error_get_pretty().  This avoids suppressing its hint (see commit
50b7b00), but I can't see how the errors touched in this commit could
come with hints.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1450452927-8346-12-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-13 15:16:17 +01:00
Markus Armbruster
a4699e55f5 qemu-nbd: Clean up "Failed to load snapshot" error message
bdrv_snapshot_load_tmp() sets an error and returns -errno on failure.
We report both even though the error message is self-contained.  Drop
the redundant strerror().

While there: setting errno right before exit() is pointless, so drop
that, too.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1450452927-8346-8-git-send-email-armbru@redhat.com>
2016-01-13 15:16:17 +01:00
Markus Armbruster
7828867198 error: Use error_report_err() instead of ad hoc prints
Unlike ad hoc prints, error_report_err() uses the error whole instead
of just its message obtained with error_get_pretty().  This avoids
suppressing its hint (see commit 50b7b00).  Example:

    $ bld/ivshmem-server -l 42@
    Parameter 'shm_size' expects a size
    You may use k, M, G or T suffixes for kilobytes, megabytes, gigabytes and terabytes.

The last line is new with this patch.

While there, drop a "cannot parse shm size: " message prefix; it's
redundant, because the error message proper is always of the form
"Parameter 'shm_size' expects ...".

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1450452927-8346-5-git-send-email-armbru@redhat.com>
2016-01-13 15:16:16 +01:00
Markus Armbruster
4fffeb5e19 error: Use error_report_err() where appropriate (again)
Same Coccinelle semantic patch as in commit 565f65d.

We now use the original error whole instead of just its message
obtained with error_get_pretty().  This avoids suppressing its hint
(see commit 50b7b00), but I don't think the errors touched in this
commit can come with hints.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1450452927-8346-3-git-send-email-armbru@redhat.com>
2016-01-13 15:16:16 +01:00
Markus Armbruster
85b01e0960 qemu-nbd: Replace BSDism <err.h> by error_report()
Coccinelle semantic patch

    @@
    expression E;
    expression list ARGS;
    @@
    -       errx(E, ARGS);
    +       error_report(ARGS);
    +       exit(E);
    @@
    expression E, FMT;
    expression list ARGS;
    @@
    -       err(E, FMT, ARGS);
    +       error_report(FMT /*": %s"*/, ARGS, strerror(errno));
    +       exit(E);

followed by a replace of '"/*": %s"*/' by ' : %s"', because I can't
figure out how to make Coccinelle transform strings.

A few of the error messages touched have trailing newlines.  They'll
be stripped later in this series.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1450452927-8346-2-git-send-email-armbru@redhat.com>
2016-01-13 15:16:16 +01:00
Eric Blake
7fb1cf1606 qapi: Don't let implicit enum MAX member collide
Now that we guarantee the user doesn't have any enum values
beginning with a single underscore, we can use that for our
own purposes.  Renaming ENUM_MAX to ENUM__MAX makes it obvious
that the sentinel is generated.

This patch was mostly generated by applying a temporary patch:

|diff --git a/scripts/qapi.py b/scripts/qapi.py
|index e6d014b..b862ec9 100644
|--- a/scripts/qapi.py
|+++ b/scripts/qapi.py
|@@ -1570,6 +1570,7 @@ const char *const %(c_name)s_lookup[] = {
|     max_index = c_enum_const(name, 'MAX', prefix)
|     ret += mcgen('''
|     [%(max_index)s] = NULL,
|+// %(max_index)s
| };
| ''',
|                max_index=max_index)

then running:

$ cat qapi-{types,event}.c tests/test-qapi-types.c |
    sed -n 's,^// \(.*\)MAX,s|\1MAX|\1_MAX|g,p' > list
$ git grep -l _MAX | xargs sed -i -f list

The only things not generated are the changes in scripts/qapi.py.

Rejecting enum members named 'MAX' is now useless, and will be dropped
in the next patch.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-23-git-send-email-eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Rebased to current master, commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-12-17 08:21:28 +01:00
Eric Blake
2d32addae7 sockets: Convert to new qapi union layout
We have two issues with our qapi union layout:
1) Even though the QMP wire format spells the tag 'type', the
C code spells it 'kind', requiring some hacks in the generator.
2) The C struct uses an anonymous union, which places all tag
values in the same namespace as all non-variant members. This
leads to spurious collisions if a tag value matches a non-variant
member's name.

Make the conversion to the new layout for socket-related code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-17-git-send-email-eblake@redhat.com>
[Commit message tweaked slightly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-11-02 08:30:27 +01:00
Stefan Hajnoczi
bb628e1af8 qemu-nbd: always compile in --aio=MODE option
The --aio=MODE option enables Linux AIO or Windows overlapped I/O.

The #ifdef CONFIG_LINUX_AIO was a layering violation that also prevented
Windows overlapped I/O from being used.

Now that raw-posix.c prints an error when Linux AIO has not been
compiled in, we can unconditionally compile the option into qemu-nbd.

After this patch qemu-nbd --aio=native works on Windows.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-10-16 15:34:30 +02:00
Daniel P. Berrange
48bec07e8d qemu-nbd: convert to use the QAPI SocketAddress object
The qemu-nbd program currently uses a QemuOpts objects
when setting up sockets. Switch it over to use the
QAPI SocketAddress objects instead.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442411543-28513-3-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-25 12:04:40 +02:00
Andrey Korolyov
6883de6c9b Trivial: fix commandline help message
Fix obvious typo in printed help for qemu-nbd.

Signed-off-by: Andrey Korolyov <andrey@xdel.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:21:38 +03:00
Paolo Bonzini
06832648e1 qemu-nbd: remove unnecessary qemu_notify_event()
This was needed when qemu-nbd was using qemu_set_fd_handler2.  It is
not needed anymore now that nbd_update_server_fd_handler is called
whenever nbd_can_accept() can change from false to true.
nbd_update_server_fd_handler will call qemu_set_fd_handler(),
which will call qemu_notify_event().

Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-14 23:40:32 +02:00
Markus Armbruster
d49b683644 qerror: Move #include out of qerror.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:40 +02:00
Markus Armbruster
70b9433109 QemuOpts: Wean off qerror_report_err()
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>
2015-06-22 18:20:39 +02:00
Fam Zheng
e4afbf4fb4 qemu-nbd: Switch to qemu_set_fd_handler
Achieved by:

- Remembering the server fd with a global variable, in order to access
  it from nbd_client_closed.

- Checking nbd_can_accept() and updating server_fd handler whenever
  client connects or disconnects.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1432032670-15124-3-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-06-05 17:09:58 +02:00
Max Reitz
3f4726596d nbd: Set block size to BDRV_SECTOR_SIZE
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1424887718-10800-13-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-18 12:07:01 +01:00
Max Reitz
ac97393dc7 nbd: Fix potential signed overflow issues
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1424887718-10800-11-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-18 12:06:56 +01:00
Max Reitz
70d4739ef2 qemu-nbd: fork() can fail
It is very unlikely, but it is possible.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1424887718-10800-10-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-18 12:06:54 +01:00
Max Reitz
98f44bbe70 nbd: Handle blk_getlength() failure
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1424887718-10800-9-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-18 12:06:50 +01:00
Max Reitz
453b07b134 qemu-nbd: Detect unused partitions by system == 0
Unused partitions do not necessarily have a total sector count of 0
(although they should have), but they always do have the system field
set to 0, so use that for testing whether a partition is in use rather
than the sector count field alone.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1424887718-10800-3-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-03-18 12:05:36 +01:00
Peter Maydell
c5c6d7f81a Clean up around error_get_pretty(), qerror_report_err()
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Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2015-02-18' into staging

Clean up around error_get_pretty(), qerror_report_err()

# gpg: Signature made Wed Feb 18 10:10:07 2015 GMT using RSA key ID EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"

* remotes/armbru/tags/pull-error-2015-02-18:
  qemu-char: Avoid qerror_report_err() outside QMP command handlers
  qemu-img: Avoid qerror_report_err() outside QMP command handlers
  vl: Avoid qerror_report_err() outside QMP command handlers
  tpm: Avoid qerror_report_err() outside QMP command handlers
  numa: Avoid qerror_report_err() outside QMP command handlers
  net: Avoid qerror_report_err() outside QMP command handlers
  monitor: Avoid qerror_report_err() outside QMP command handlers
  monitor: Clean up around monitor_handle_fd_param()
  error: Use error_report_err() where appropriate
  error: New convenience function error_report_err()
  vhost-scsi: Improve error reporting for invalid vhostfd

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-02-26 07:01:08 +00:00
Markus Armbruster
565f65d271 error: Use error_report_err() where appropriate
Coccinelle semantic patch:

    @@
    expression E;
    @@
    -    error_report("%s", error_get_pretty(E));
    -    error_free(E);
    +    error_report_err(E);
    @@
    expression E, S;
    @@
    -    error_report("%s", error_get_pretty(E));
    +    error_report_err(E);
    (
         exit(S);
    |
         abort();
    )

Trivial manual touch-ups in block/sheepdog.c.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-02-18 10:51:09 +01:00
Max Reitz
4fbec260ae qemu-nbd: Use blk_new_open() in main()
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1423162705-32065-11-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-02-16 15:07:18 +00:00
Max Reitz
1ce52846d3 nbd: Improve error messages
This patch makes use of the Error object for nbd_receive_negotiate() so
that errors during negotiation look nicer.

Furthermore, this patch adds an additional error message if the received
magic was wrong, but would be correct for the other protocol version,
respectively: So if an export name was specified, but the NBD server
magic corresponds to an old handshake, this condition is explicitly
signaled to the user, and vice versa.

As these messages are now part of the "Could not open image" error
message, additional filtering has to be employed in iotest 083, which
this patch does as well.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:22 +01:00
Max Reitz
4c58e80acd qemu-nbd: Use BlockBackend where reasonable
Because qemu-nbd creates the BlockBackend by itself, it should create
the according BlockDriverState tree by itself as well; that means, it
has call bdrv_open() on its own. This is one of the places where
qemu-nbd still needs to use a BlockDriverState directly (the root BDS
below the BB); other places are the configuration of zero detection
(which may be lifted into the BB eventually, but is not yet) and
temporarily loading a snapshot.

Everywhere else, though, qemu-nbd can and thus should use BlockBackend.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1416309679-333-7-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:12 +01:00
Max Reitz
e140177d9c nbd: Change external interface to BlockBackend
Substitute BlockDriverState by BlockBackend in every globally visible
function provided by nbd.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1416309679-333-5-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:12 +01:00
Markus Armbruster
9ba10c95a4 block: Make BlockBackend own its BlockDriverState
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>
2014-10-20 13:41:26 +02:00
Markus Armbruster
7e7d56d9e0 block: Connect BlockBackend to BlockDriverState
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>
2014-10-20 13:41:26 +02:00
Markus Armbruster
26f54e9a3c block: New BlockBackend
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>
2014-10-20 13:41:26 +02:00
Markus Armbruster
e4e9986b1c block: Split bdrv_new_root() off bdrv_new()
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>
2014-10-20 13:41:26 +02:00
Markus Armbruster
fbf28a4328 block: Drop superfluous conditionals around qemu_opts_del()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1411999675-14533-1-git-send-email-armbru@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-10-03 10:30:33 +01:00
Markus Armbruster
e5d7bbeb10 qemu-nbd: Destroy the BlockDriverState properly
Match the bdrv_new() with a bdrv_unref(), just to be tidy.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-25 15:24:14 +02:00
Chrysostomos Nanakos
2f78e491d7 async: aio_context_new(): Handle event_notifier_init failure
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>
2014-09-22 11:39:48 +01:00
Peter Lieven
713cc671f1 qemu-nbd: fix indentation and coding style
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit.canet@nodalink.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-08 11:12:43 +01:00
Peter Lieven
b3838a4088 qemu-nbd: add option to set detect-zeroes mode
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit.canet@nodalink.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-08 11:12:43 +01:00
Hani Benhabiles
27e5eae457 nbd: Shutdown socket before closing.
This forces finishing data sending to client before closing the socket like in
exports listing or replying with NBD_REP_ERR_UNSUP cases.

Signed-off-by: Hani Benhabiles <kroosec@gmail.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-30 12:50:12 +02:00
Markus Armbruster
3775ec6f5a qemu-nbd: Don't use qerror_report()
qerror_report() is a transitional interface to help with converting
existing HMP commands to QMP.  It should not be used elsewhere.
Replace by error_report().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-05-28 14:28:46 +02:00
Hani Benhabiles
5672ee54d5 nbd: Miscellaneous typo fixes.
Signed-off-by: Hani Benhabiles <hani@linux.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-05-24 00:07:29 +04:00
Hani Benhabiles
36af599417 nbd: Close socket on negotiation failure.
Otherwise, the nbd client may hang waiting for the server response.

Signed-off-by: Hani Benhabiles <hani@linux.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-05-24 00:07:29 +04:00
Kevin Wolf
98522f63f4 block: Add errp to bdrv_new()
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>
2014-04-22 12:00:20 +02:00
Paolo Bonzini
0c544d73bb qemu-nbd: Fix coverity issues
There are two issues in qemu-nbd: a missing return value check after
calling accept(), and file descriptor leaks in nbd_client_thread.

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-03-17 13:21:11 +01:00
Peter Maydell
e7a1d6c52a Block patches
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block patches

# gpg: Signature made Fri 21 Feb 2014 21:42:24 GMT using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream: (54 commits)
  iotests: Mixed quorum child device specifications
  quorum: Simplify quorum_open()
  quorum: Add unit test.
  quorum: Add quorum_open() and quorum_close().
  quorum: Implement recursive .bdrv_recurse_is_first_non_filter in quorum.
  quorum: Add quorum_co_flush().
  quorum: Add quorum_invalidate_cache().
  quorum: Add quorum_getlength().
  quorum: Add quorum mechanism.
  quorum: Add quorum_aio_readv.
  blkverify: Extract qemu_iovec_clone() and qemu_iovec_compare() from blkverify.
  quorum: Add quorum_aio_writev and its dependencies.
  quorum: Create BDRVQuorumState and BlkDriver and do init.
  quorum: Create quorum.c, add QuorumChildRequest and QuorumAIOCB.
  check-qdict: Test termination of qdict_array_split()
  check-qdict: Adjust test for qdict_array_split()
  qdict: Extract non-QDicts in qdict_array_split()
  qemu-config: Sections must consist of keys
  qemu-iotests: Check qemu-img command line parsing
  qemu-img: Allow -o help with incomplete argument list
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-25 10:50:11 +00:00
Paolo Bonzini
537b41f501 nbd: move socket wrappers to qemu-nbd
qemu-nbd is one of the few valid users of qerror_report_err.  Move
the error-reporting socket wrappers there.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:23 +01:00
Max Reitz
ddf5636dc9 block: Add reference parameter to bdrv_open()
Allow bdrv_open() to handle references to existing block devices just as
bdrv_file_open() is already capable of.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:22 +01:00
Max Reitz
f67503e5bd block: Change BDS parameter of bdrv_open() to **
Make bdrv_open() take a pointer to a BDS pointer, similarly to
bdrv_file_open(). If a pointer to a NULL pointer is given, bdrv_open()
will create a new BDS with an empty name; if the BDS pointer is not
NULL, that existing BDS will be reused (in the same way as bdrv_open()
already did).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:21 +01:00
Fam Zheng
10f5bff622 util: Split out exec_dir from os_find_datadir
With this change, main() calls qemu_init_exec_dir and uses argv[0] to
init exec_dir. The saved value can be retrieved with
qemu_get_exec_dir later. It will be reused by module loading.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-02-20 13:12:54 +01:00
Wenchao Xia
4323fdcf94 qemu-nbd: add doc for option -f
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-04 15:19:00 +01:00