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>

This extends the NBD protocol handling code so that it is capable
of negotiating TLS support during the connection setup. This involves
requesting the STARTTLS protocol option before any other NBD options.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-14-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

If the user does not provide an export name and the server
is running the new style protocol, where export names are
mandatory, use "" as the default export name if the user
has not specified any. "" is defined in the NBD protocol
as the default name to use in such scenarios.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-13-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

With the new style protocol, the NBD client will currenetly
send NBD_OPT_EXPORT_NAME as the first (and indeed only)
option it wants. The problem is that the NBD protocol spec
does not allow for returning an error message with the
NBD_OPT_EXPORT_NAME option. So if the server mandates use
of TLS, the client will simply see an immediate connection
close after issuing NBD_OPT_EXPORT_NAME which is not user
friendly.

To improve this situation, if we have the fixed new style
protocol, we can sent NBD_OPT_LIST as the first option
to query the list of server exports. We can check for our
named export in this list and raise an error if it is not
found, instead of going ahead and sending NBD_OPT_EXPORT_NAME
with a name that we know will be rejected.

This improves the error reporting both in the case that the
server required TLS, and in the case that the client requested
export name does not exist on the server.

If the server does not support NBD_OPT_LIST, we just ignore
that and carry on with NBD_OPT_EXPORT_NAME as before.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-12-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

If the server advertises support for the fixed new style
negotiation, the client should in turn enable new style.
This will allow the client to negotiate further NBD
options besides the export name.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-10-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

If the client does not request the fixed new style protocol,
then we should only accept NBD_OPT_EXPORT_NAME. All other
options are only valid when fixed new style has been activated.

The qemu-nbd client doesn't currently request fixed new style
protocol, but this change won't break qemu-nbd, because it
fortunately only ever uses NBD_OPT_EXPORT_NAME, so was never
triggering the non-compliant server behaviour.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-9-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The nbd_receive_negotiate() method takes different code
paths based on whether 'name == NULL', and then checks
the expected protocol version in each branch.

This patch inverts the logic, so that it takes different
code paths based on what protocol version it receives and
then checks if name is NULL or not as needed.

This facilitates later code which allows the client to
be capable of using the new style protocol regardless
of whether an export name is listed or not.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-8-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Now that all callers are converted to use I/O channels for
initial connection setup, it is possible to switch the core
NBD protocol handling core over to use QIOChannel APIs for
actual sockets I/O.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-7-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

cpu_to_be64w can't be used to make unaligned stores, but stq_be_p can.
Also, the st?_be_p takes a void* so it is more clearly suited to the
case where you're writing into a byte buffer.

Use the st?_be_p family of functions everywhere in nbd/server.c.

Signed-off-by: John Snow <jsnow@redhat.com>
[Changed to use st?_be_p everywhere. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@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>
Message-id: 1454089805-5470-16-git-send-email-peter.maydell@linaro.org

The NBD code uses the BDS close notifier to determine when a medium is
ejected. However, now it should use the BB's BDS removal notifier for
that instead of the BDS's close notifier.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Use client_close() if an error in nbd_co_client_start() occurs instead
of manually inlining parts of it. This fixes an assertion error on the
server side if nbd_negotiate() fails.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

blk_invalidate_cache() can call qcow2_invalidate_cache which performs
IO inside.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1453273940-15382-3-git-send-email-den@openvz.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Instead of covering only the state of images on the migration
destination before the migration is completed, the flag will also cover
the state of images on the migration source after completion. This
common state implies that the image is technically still open, but no
writes will happen and any cached contents will be reloaded from disk if
and when the image leaves this state.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

The amount of memory allocated in nbd_co_receive_request is driven by the
NBD client (possibly a virtual machine).  Parallel I/O can cause the
server to allocate a large amount of memory; check for failures and
return ENOMEM in that case.

Cc: qemu-block@nongnu.org
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Only reads and writes need to allocate memory correspondent to the
request length.  Other requests can be sent to the storage without
allocating any memory, and thus any request length is acceptable.

Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Cc: qemu-block@nongnu.org
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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>