Commit Graph

66 Commits

Author SHA1 Message Date
Alex Bligh 6a1751b7aa aio / timers: Untangle include files
include/qemu/timer.h has no need to include main-loop.h and
doing so causes an issue for the next patch. Unfortunately
various files assume including timers.h will pull in main-loop.h.
Untangle this mess.

Signed-off-by: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 19:10:27 +02:00
Daniel P. Berrange e6b636779b Add -f FMT / --format FMT arg to qemu-nbd
Currently the qemu-nbd program will auto-detect the format of
any disk it is given. This behaviour is known to be insecure.
For example, if qemu-nbd initially exposes a 'raw' file to an
unprivileged app, and that app runs

   'qemu-img create -f qcow2 -o backing_file=/etc/shadow /dev/nbd0'

then the next time the app is started, the qemu-nbd will now
detect it as a 'qcow2' file and expose /etc/shadow to the
unprivileged app.

The only way to avoid this is to explicitly tell qemu-nbd what
disk format to use on the command line, completely disabling
auto-detection. This patch adds a '-f' / '--format' arg for
this purpose, mirroring what is already available via qemu-img
and qemu commands.

  qemu-nbd --format raw -p 9000 evil.img

will now always use raw, regardless of what format 'evil.img'
looks like it contains

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
[Use errx, not err. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-15 14:29:20 -05:00
Kevin Wolf de9c0cec6c block: Add options QDict to bdrv_open() prototype
It doesn't do anything yet except storing the options QDict in the
BlockDriverState.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-15 16:07:49 +01:00
Paolo Bonzini ded9d2d5e2 qemu-nbd: add --discard option
Similar to --cache and --aio, this option mimics the discard suboption
of "-drive".

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-02-22 21:29:43 +01:00
Paolo Bonzini 737e150e89 block: move include files to include/block/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:31:31 +01:00
Paolo Bonzini 7e7f4a0efc qemu-nbd: initialize main loop before block layer
qemu-nbd was broken because they initialized the block layer while
qemu_aio_context was still NULL.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-11-12 11:33:29 +01:00
Paolo Bonzini 7860a380ac qemu-nbd: rewrite termination conditions to use a state machine
Use a simple state machine with the following states:

- RUNNING     => accepting connections
- TERMINATE   => main loop must call nbd_export_close/put, and not accept
  connections anymore
- TERMINATING => waiting for pending requests to finish
- TERMINATED  => the NBDExport has been closed

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-09-19 15:26:29 +02:00
Paolo Bonzini 0ddf08db22 nbd: add notification for closing an NBDExport
In order to exit cleanly from qemu-nbd, add a callback that triggers
when an NBDExport is closed.  In the case of qemu-nbd it will exit the
main loop.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-09-19 15:26:29 +02:00
Paolo Bonzini 2c8d9f0655 nbd: add reference counting to NBDExport
We will use a similar two-phase destruction for NBDExport, so we need
each NBDClient to add a reference to NBDExport.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-09-19 15:26:28 +02:00
Paolo Bonzini a4aab7b4cb nbd: do not close BlockDriverState in nbd_export_close
This is not desirable when embedding the NBD server inside QEMU.
Move the bdrv_close to qemu-nbd.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-09-19 15:26:15 +02:00
Paolo Bonzini 39a5235cd7 qemu-nbd: add --cache and --aio options
Add two options to tune the I/O implementation of qemu-nbd, matching
the possibilities given by the QEMU -drive option.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-07-24 09:31:53 +02:00
Paolo Bonzini b033cd8640 qemu-nbd: reorganize help message
This patch separates qemu-nbd's options in logical groups, thus making
the help message easier to read.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-07-24 09:31:53 +02:00
Paolo Bonzini 38ceff0412 nbd: do not include block_int.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-04-19 17:19:37 +02:00
Paolo Bonzini 185b43386a nbd: consistently return negative errno values
In the next patch we need to look at the return code of nbd_wr_sync.
To avoid percolating the socket_error() ugliness all around, let's
handle errors by returning negative errno values.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-04-19 16:36:43 +02:00
Paolo Bonzini fc19f8a02e nbd: consistently check for <0 or >=0
This prepares for the following patch, which changes -1 return values
to negative errno.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-04-19 16:36:43 +02:00
Paolo Bonzini a6ac2313a8 open /dev/nbd in nbd_client_thread
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-02-17 12:41:59 +01:00
Michael Tokarev 9faf31b68f do not chdir(/) in qemu-nbd before opening all files
When qemu-nbd becomes a daemon it calls daemon(3) with
nochdir=0, so daemon(3) changes current directory to /.
But at this time, qemu-nbd did not open any user-specified
files yet, so by changing current directory, all non-absolute
paths becomes wrong.  The solution is to pass nochdir=1 to
daemon(3) function, and to chdir("/") after all init has
been performed, before entering the main loop, -- just like
a good daemon should do.

This patch is applicable for -stable.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-02-17 12:41:48 +01:00
Stefan Hajnoczi dc10e8b3c5 qemu-nbd: drop loop which can never loop
For some reason nbd_client_thread() has a do..while loop which can never
loop, the condition is bogus because we would take a goto instead.  Drop
the loop.

Reported-by: Dr David Alan Gilbert <davidagilbert@uk.ibm.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-01-06 15:09:53 +00:00
Paolo Bonzini 1743b51586 qemu-nbd: move client handling to nbd.c
This patch sets up the fd handler in nbd.c instead of qemu-nbd.c.  It
introduces NBDClient, which wraps the arguments to nbd_trip in a single
structure, so that we can add a notifier to it.  This way, qemu-nbd can
know about disconnections.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2011-12-22 11:53:59 +01:00
Paolo Bonzini a61c67828d qemu-nbd: use common main loop
Using a single main loop for sockets will help yielding from the socket
coroutine back to the main loop, and later reentering it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2011-12-22 11:53:59 +01:00
Paolo Bonzini af49bbbe78 qemu-nbd: introduce NBDExport
Wrap the common parameters of nbd_trip and nbd_negotiate in a
single opaque struct.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2011-12-22 11:53:58 +01:00
Paolo Bonzini 3777b09fd7 qemu-nbd: remove data_size argument to nbd_trip
The size of the buffer is in practice part of the protocol.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2011-12-22 11:53:58 +01:00
Paolo Bonzini 94607e7a77 qemu-nbd: remove offset argument to nbd_trip
The argument is write-only.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2011-12-22 11:53:58 +01:00
Paolo Bonzini 802ddc375a qemu-nbd: open the block device after starting the client thread
This is cleaner, because we do not need to close the block device when
there is an error opening /dev/nbdX.  It was done this way only to
print errors before daemonizing.

At the same time, use atexit to ensure that the block device is closed
whenever we exit.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-11 14:02:58 +01:00
Paolo Bonzini f1ef5555c2 qemu-nbd: fix socket creation race
Now that the client and server are in the same process, there is
no need to race on the creation of the socket.  We can open the
listening socket before starting the client thread.

This avoids that "qemu-nbd -v -c" prints this once before connecting
successfully to the socket:

    connect(unix:/var/lock/qemu-nbd-nbd0): No such file or directory

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-11 14:02:58 +01:00
Paolo Bonzini c1f8fdc362 qemu-nbd: print error messages from the daemon through a pipe
In order to get nice error messages, keep the qemu-nbd process running
until before issuing NBD_DO_IT and connected to the daemon with a pipe.
This lets the qemu-nbd process relay error messages from the daemon and
exit with a nonzero status if appropriate.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-11 14:02:58 +01:00
Paolo Bonzini a517e88baa qemu-nbd: move client to a thread
This avoids that qemu-nbd uses both forking and threads, which do
not behave well together.

qemu-nbd is already Unix only, and there is no qemu_thread_join,
so for now use pthreads.

Since the parent and child no longer have separate file descriptors,
we can open the NBD device before daemonizing, instead of checking
with access(2) and restricting the open to the client only.

Reported-by: Pierre Riteau <pierre.riteau@irisa.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-11 14:02:58 +01:00
Paolo Bonzini b32f6c28d5 qemu-nbd: rename socket variable
It will be moved to a global variable by the next patch, and it
would conflict with the socket function.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-11 14:02:58 +01:00
Paolo Bonzini bb345110f0 qemu-nbd: trap SIGTERM
The client process right now uses SIGTERM to interrupt the server side.
This does not affect the exit status of "qemu-nbd -v -c" because the
server is a child process.  This will change when both sides will be
in the same process, and anyway cleaning up things nicely upon SIGTERM
is good practice.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-11 14:02:58 +01:00
Paolo Bonzini b90fb4b8f5 nbd: support feature negotiation
nbd supports writing flags in bytes 24...27 of the header,
and uses that for the read-only flag.  Add support for it
in qemu-nbd.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-09-19 11:34:33 +02:00
Stefan Weil 5a61cb60d6 Fix include statements for qemu-common.h
* qemu-common.h is not a system include file, so it should be included
  with "" instead of <>. Otherwise incremental builds might fail
  because only local include files are checked for changes.

* linux-user/syscall.c included the file twice.

Cc: Riku Voipio <riku.voipio@iki.fi>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-09-09 09:56:12 +01:00
Anthony Liguori 7267c0947d Use glib memory allocation and free functions
qemu_malloc/qemu_free no longer exist after this commit.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-20 23:01:08 -05:00
Alexandre Raymond f97742d0d3 Darwin: Fix compilation warning regarding the deprecated daemon() function
Changes since v1: create a wrapper function named qemu_daemon() in oslib-posix.c
instead of putting the OS specific workaround in qemu-nbd.c directly.

On OSX >= 10.5, daemon() is deprecated, resulting in the following warning:
----8<----
qemu-nbd.c: In function ‘main’:
qemu-nbd.c:371: warning: ‘daemon’ is deprecated (declared at /usr/include/stdlib.h:289)
----8<----

The following trick, used in mDNSResponder, takes care of this warning:
http://www.opensource.apple.com/source/mDNSResponder/mDNSResponder-258.18/mDNSPosix/PosixDaemon.c

On OSX, it temporarily renames the daemon() function before including stdlib.h
and declares it manually as an extern function. This way, the compiler does not
see the declaration from stdlib.h and thus does not display the warning.

Signed-off-by: Alexandre Raymond <cerbere@gmail.com>
Cc: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Andreas Färber <andreas.faerber@web.de>
2011-06-14 03:10:47 +02:00
Christoph Hellwig a659979328 block: clarify the meaning of BDRV_O_NOCACHE
Change BDRV_O_NOCACHE to only imply bypassing the host OS file cache,
but no writeback semantics.  All existing callers are changed to also
specify BDRV_O_CACHE_WB to give them writeback semantics.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 10:39:32 +02:00
Kevin Wolf ad7171394f Remove NULL checks for bdrv_new return value
It's an indirect call to qemu_malloc, which never returns an error.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17 16:11:03 +01:00
Laurent Vivier c2e2872bf4 nbd: correctly manage default port
block/nbd.c: use default port number when none is specified
qemu-nbd.c:  use IANA-assigned port number: 10809

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:42 +02:00
Christoph Hellwig 72aef7318f use qemu_blockalign consistently
Use qemu_blockalign for all allocations in the block layer.  This allows
increasing the required alignment, which is need to support O_DIRECT on
devices with large block sizes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:42 +02:00
Anthony Liguori aab2e8f79a Merge remote branch 'kwolf/for-anthony' into staging 2010-09-08 14:26:57 -05:00
Jes Sorensen e301b13d6a Respect return value from nbd_client()
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-09-04 09:45:51 +00:00
Jes Sorensen 0a4eb864e3 Remove unused argument for nbd_client()
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-09-04 09:45:50 +00:00
Laurent Vivier 1d45f8b542 nbd: Introduce NBD named exports.
This patch allows to connect Qemu using NBD protocol to an nbd-server
using named exports.

For instance, if on the host "isoserver", in /etc/nbd-server/config, you have:

[generic]
[debian-500-ppc-netinst]
        exportname = /ISO/debian-500-powerpc-netinst.iso
[Fedora-10-ppc-netinst]
        exportname = /ISO/Fedora-10-ppc-netinst.iso

You can connect to it, using:

    qemu -cdrom nbd:isoserver:exportname=debian-500-ppc-netinst
    qemu -cdrom nbd:isoserver:exportname=Fedora-10-ppc-netinst

NOTE: you need at least nbd-server 2.9.18

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-08-30 18:29:22 +02:00
Ryota Ozaki cb7cf0e3f4 qemu-nbd: Improve error reporting
- use err(3) instead of errx(3) if errno is available
  to report why failed
- let fail prior to daemon(3) if opening a nbd file
  is likely to fail after daemonizing to avoid silent
  failure exit
- add missing 'ret = 1' when unix_socket_outgoing failed

Signed-off-by: Ryota Ozaki <ozaki.ryota@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:04 +02:00
Kevin Wolf d6e9098e10 Replace calls of old bdrv_open
What is known today as bdrv_open2 becomes the new bdrv_open. All remaining
callers of the old function are converted to the new one. In some places they
even know the right format, so they should have used bdrv_open2 from the
beginning.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-04-23 16:08:46 +02:00
Ryota Ozaki b6353bea57 qemu-nbd: Fix invalid usage of the first argument of errx
errx takes the exit status of a process as the first
argument. Passing errno to it is wrong. Instead the
patch lets errx take EXIT_FAILURE.

Signed-off-by: Ryota Ozaki <ozaki.ryota@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-03-27 14:02:46 +01:00
Ryota Ozaki a16c174c51 qemu-nbd: Fix return value handling of bdrv_open
bdrv_open may return -errno so we have to check
if the return value is '< 0', not '== -1'.

Signed-off-by: Ryota Ozaki <ozaki.ryota@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-03-27 13:56:17 +01:00
Naphtali Sprei 07108b29c5 read-only: minor cleanup
Really use read-only flags for opening the file when asked for read-only

Signed-off-by: Naphtali Sprei <nsprei@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-03-17 11:16:15 -05:00
Herve Poussineau f8a83245d9 win32: pair qemu_memalign() with qemu_vfree()
Win32 suffers from a very big memory leak when dealing with SCSI devices.
Each read/write request allocates memory with qemu_memalign (ie
VirtualAlloc) but frees it with qemu_free (ie free).
Pair all qemu_memalign() calls with qemu_vfree() to prevent such leaks.

Signed-off-by: Herve Poussineau <hpoussin@reactos.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-26 16:41:06 -06:00
Naphtali Sprei f5edb014ed Clean-up a little bit the RW related bits of BDRV_O_FLAGS. BDRV_O_RDONLY gone (and so is BDRV_O_ACCESS). Default value for bdrv_flags (0/zero) is READ-ONLY. Need to explicitly request READ-WRITE.
Instead of using the field 'readonly' of the BlockDriverState struct for passing the request,
pass the request in the flags parameter to the function.

Signed-off-by: Naphtali Sprei <nsprei@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-01-20 08:25:22 -06:00
Blue Swirl 22ff51ee64 qemu-nbd: fix OpenBSD linker warning
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2009-12-23 15:45:30 +00:00
Blue Swirl 2bff4b6fbe Compile qemu-nbd also on OpenBSD and Solaris
basename() needs #include <libgen.h>.

No prototype for daemon() is available on Solaris, but link
succeeds.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2009-12-23 15:34:04 +00:00