Create a coroutine in nbd_client_new, so that nbd_send_negotiate doesn't
need qemu_set_block().
Handlers need to be set temporarily for csock fd in case the coroutine
yields during I/O.
With this, if the other end disappears in the middle of the negotiation,
we don't block the whole event loop.
To make the code clearer, unify all function names that belong to
negotiate, so they are less likely to be misused. This is important
because we rely on negotiation staying in main loop, as commented in
nbd_negotiate_read/write().
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1452760863-25350-4-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We have NBD server code and client code, all mixed in a file. Now split
them into separate files under nbd/, and update MAINTAINERS.
filter_nbd for iotest 083 is updated to keep the log filtered out.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1452760863-25350-3-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
So we could distinguish it from internal used fds, thus avoid handling
unwanted events in nested aio polls.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
All callers pass in false, and the real external ones will switch to
true in coming patches.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The coroutine files are currently referenced by the block-obj-y
variable. The coroutine functionality though is already used by
more than just the block code. eg migration code uses coroutine
yield. In the future the I/O channel code will also use the
coroutine yield functionality. Since the coroutine code is nicely
self-contained it can be easily built as part of the libqemuutil.a
library, making it widely available.
The headers are also moved into include/qemu, instead of the
include/block directory, since they are now part of the util
codebase, and the impl was never in the block/ directory
either.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Simplify memory allocation by sticking with a single API. GSlice
is not that fast anyway (tcmalloc/jemalloc are better).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If the socket fd is shutdown, there may be some data which is received before
shutdown. We will read the data and do read/write in nbd_trip(). But the exp's
blk is NULL, and it will cause qemu crashed.
Reported-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Message-Id: <55F929E2.1020501@cn.fujitsu.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Right now, NBD includes potentially platform-specific error values in
the wire protocol.
Luckily, most common error values are more or less universal: in
particular, of all errno values <= 34 (up to ERANGE), they are all the
same on supported platforms except for 11 (which is EAGAIN on Windows and
Linux, but EDEADLK on Darwin and the *BSDs). So, in order to guarantee
some portability, only keep a handful of possible error codes and squash
everything else to EINVAL.
This patch defines a limited set of errno values that are valid for the
NBD protocol, and specifies recommendations for what error to return
in specific corner cases. The set of errno values is roughly based on
the errors listed in the read(2) and write(2) man pages, with some
exceptions:
- ENOMEM is added for servers that implement copy-on-write or other
formats that require dynamic allocation.
- EDQUOT is not part of the universal set of errors; it can be changed
to ENOSPC on the wire format.
- EFBIG is part of the universal set of errors, but it is also changed
to ENOSPC because it is pretty similar to ENOSPC or EDQUOT.
Incoming values will in general match system errno values, but not
on the Hurd which has different errno values (they have a "subsystem
code" equal to 0x10 in bits 24-31). The Hurd is probably not something
to which QEMU has been ported, but still do the right thing and
reverse-map the NBD errno values to the system errno values.
The corresponding patch to the NBD protocol description can be found at
http://article.gmane.org/gmane.linux.drivers.nbd.general/3154.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This fixes ioctl behavior on powerpc e6500 platforms with 64bit kernel and 32bit
userspace. The current type cast has no effect there and the value passed to the
kernel is still 0. Probably an issue related to the compiler, since I'm assuming
the same configuration works on a similar setup on x86.
Also ensure consistency with previous type cast in TRACE message.
Signed-off-by: Bogdan Purcareata <bogdan.purcareata@freescale.com>
Message-Id: <1428058914-32050-1-git-send-email-bogdan.purcareata@freescale.com>
Cc: qemu-stable@nongnu.org
[Fix parens as noticed by Michael. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When requesting the list of exports, no data should be sent. If data is
sent, the NBD server should not just inform the client of the invalid
request, but also drop the data.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1424887718-10800-22-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The export flags are a 16 bit value, so be16_to_cpu() has to be used to
interpret them correctly. This makes discard and flush actually work
for named NBD exports (they did not work before, because the client
always assumed them to be unsupported because of the bug fixed by this
patch).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1424887718-10800-20-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The client flags are sent exactly once overall, not once per option.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1424887718-10800-19-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
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>
While it does not make a difference in practice, nbd_receive_options()
generally returns -errno, so it should do that here as well; and the
easiest way to achieve this is by passing on the value returned by
nbd_handle_list().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <1424887718-10800-7-git-send-email-mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The value of reply.error should be the type unsigned int.
Signed-off-by: Yik Fang <eric.fangyi@huawei.com>
Message-Id: <1423722111-12902-1-git-send-email-eric.fangyi@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Before this patch, the "opaque" pointer in an NBD BDS points to a
BDRVNBDState, which contains an NbdClientSession object, which in turn
contains a pointer to the BDS. This pointer may become invalid due to
bdrv_swap(), so drop it, and instead pass the BDS directly to the
nbd-client.c functions which then retrieve the NbdClientSession object
from there.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1423256778-3340-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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>
With all externally visible functions changed to use BlockBackend, this
patch makes nbd use BlockBackend for everything internally as well.
While touching them, substitute 512 by BDRV_SECTOR_SIZE in the calls to
blk_read(), blk_write() and blk_co_discard().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1416309679-333-6-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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>
When migrated using libvirt with "--copy-storage-all", at the end of
migration there is race between NBD mirroring task trying to do flush
and migration completion, both end up invalidating cache. Since qcow2
driver does not handle this situation very well, random crashes happen.
This disables the BDRV_O_INCOMING flag for the block device being migrated
once the cache has been invalidated.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
--
fixed parens by hand
Signed-off-by: Juan Quintela <quintela@redhat.com>
Keep the NBD server always in the same AIO context as the exported BDS
by calling bdrv_add_aio_context_notifier() and implementing the required
callbacks.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
There is no variant of aio_set_fd_handler() like qemu_set_fd_handler2(),
so we cannot give a can_read() callback function. Instead, unregister
the nbd_read() function whenever we cannot read and re-register it as
soon as we can read again.
All this is hidden behind the functions nbd_set_handlers() (which
registers all handlers for the AIO context and file descriptor belonging
to the given client), nbd_unset_handlers() (which unregisters them) and
nbd_update_can_read() (which checks whether NBD can read for the given
client and acts accordingly).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When this flag is set, the server tells the client that it can send another
option if the server received a request with an option that it doesn't
understand instead of directly closing the connection.
Also add link to the most up-to-date documentation.
Signed-off-by: Hani Benhabiles <kroosec@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These values aren't used in this case.
Currently, the from field in the request sent by the nbd kernel module leading
to a false error message when ending the connection with the client.
$ qemu-nbd some.img -v
// After nbd-client -d /dev/nbd0
nbd.c:nbd_trip():L1031: From: 18446744073709551104, Len: 0, Size: 20971520,
Offset: 0
nbd.c:nbd_trip():L1032: requested operation past EOF--bad client?
nbd.c:nbd_receive_request():L638: read failed
Signed-off-by: Hani Benhabiles <kroosec@gmail.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
Before:
$ ./qemu-io-old
qemu-io-old> open -r -o file.driver=nbd
one of path and host must be specified.
qemu-io-old: can't open device (null): Could not open image: Invalid argument
$ ./qemu-io-old
qemu-io-old> open -r -o file.driver=nbd,file.host=foo,file.path=bar
path and host may not be used at the same time.
qemu-io-old: can't open device (null): Could not open image: Invalid argument
After:
$ ./qemu-io
qemu-io> open -r -o file.driver=nbd
qemu-io: can't open device (null): one of path and host must be specified.
$ ./qemu-io
qemu-io> open -r -o file.driver=nbd,file.host=foo,file.path=bar
qemu-io: can't open device (null): path and host may not be used at the same time.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The caller might handle non-blocking using coroutine. Leave the choice
to the caller to use a blocking or non-blocking negotiate.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Previously, nbd calls drive_get_ref() on the drive of bs. A BDS doesn't
always have associated dinfo, which nbd doesn't care either. We already
have BDS ref count, so use it to make it safe for a BDS w/o blockdev.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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>
The Linux nbd driver recently increased the maximum supported request
size up to 32 MB:
commit 078be02b80359a541928c899c2631f39628f56df
Author: Michal Belczyk <belczyk@bsd.krakow.pl>
Date: Tue Apr 30 15:28:28 2013 -0700
nbd: increase default and max request sizes
Raise the default max request size for nbd to 128KB (from 127KB) to get it
4KB aligned. This patch also allows the max request size to be increased
(via /sys/block/nbd<x>/queue/max_sectors_kb) to 32MB.
QEMU's 1 MB buffers are too small to handle these requests.
This patch allocates data buffers dynamically and allows up to 32 MB per
request.
Reported-by: Nick Thomas <nick@bytemark.co.uk>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Use GLib's efficient slice allocator instead of open-coding the request
freelist. This patch simplifies the NBDRequest code.
Now we qemu_blockalign() the req->data buffer each time but the next
patch switches from a fixed size buffer to a dynamic size anyway.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The fcntl(fd, F_SETFL, O_NONBLOCK) flag is not specific to sockets.
Rename to qemu_set_nonblock() just like qemu_set_cloexec().
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
The NBD block supports an URL syntax, for which a URL parser returns
separate hostname and port fields. It also supports the traditional qemu
syntax encoded in a filename. Until now, after parsing the URL to get
each piece of information, a new string is built to be fed to socket
functions.
Instead of building a string in the URL case that is immediately parsed
again, parse the string in both cases and use the QemuOpts interface to
qemu-sockets.c.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
We do not need BLKROSET if the kernel supports setting flags.
Also, always do BLKROSET even for a read-write export, otherwise
the read-only state remains "sticky" after the invocation of
"qemu-nbd -r".
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Before:
$ qemu-system-x86_64 nbd:localhost:12345
inet_connect_opts: connect(ipv4,yakj.usersys.redhat.com,127.0.0.1,12345): Connection refused
qemu-system-x86_64: could not open disk image nbd:localhost:12345: Connection refused
After:
$ x86_64-softmmu/qemu-system-x86_64 nbd:localhost:12345
qemu-system-x86_64: Failed to connect to socket: Connection refused
qemu-system-x86_64: could not open disk image nbd:localhost:12345: Connection refused
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This lets me adjust the clients to do proper error propagation first,
thus avoiding temporary regressions in the quality of the error messages.
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
No need to add non blocking parameters to the blocking inet_connect
add block parameter for inet_connect_opts instead of using QemuOpt "block".
Signed-off-by: Orit Wasserman <owasserm@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Allow negotiation to receive the name of the requested export from
the client. Passing a NULL export to nbd_client_new will cause
the server to send the extended negotiation header. The exp field
is then filled during negotiation.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fam Zheng
Daniel P. Berrange
Paolo Bonzini
Wen Congyang
Bogdan Purcareata
Max Reitz
Yik Fang
Alexey Kardashevskiy
Hani Benhabiles
Marc-André Lureau
Alex Bligh
Stefan Hajnoczi
Kevin Wolf
Orit Wasserman