https://bugzilla.redhat.com/show_bug.cgi?id=648855 mentioned a
misuse of 'an' where 'a' is proper; that has since been fixed,
but a search found other problems (some were a spelling error for
'and', while most were fixed by 'a').
* daemon/stream.c: Fix grammar.
* src/conf/domain_conf.c: Likewise.
* src/conf/domain_event.c: Likewise.
* src/esx/esx_driver.c: Likewise.
* src/esx/esx_vi.c: Likewise.
* src/rpc/virnetclient.c: Likewise.
* src/rpc/virnetserverprogram.c: Likewise.
* src/storage/storage_backend_fs.c: Likewise.
* src/util/conf.c: Likewise.
* src/util/dnsmasq.c: Likewise.
* src/util/iptables.c: Likewise.
* src/xen/xen_hypervisor.c: Likewise.
* src/xen/xend_internal.c: Likewise.
* src/xen/xs_internal.c: Likewise.
* tools/virsh.c: Likewise.
The RPC server classes are extended to allow FDs to be received
from clients with calls. There is not currently any way for a
procedure to pass FDs back to the client with replies
* daemon/remote.c, src/rpc/gendispatch.pl: Change virNetMessageHeaderPtr
param to virNetMessagePtr in dispatcher impls
* src/rpc/virnetserver.c, src/rpc/virnetserverclient.c,
src/rpc/virnetserverprogram.c, src/rpc/virnetserverprogram.h:
Extend to support FD passing
If we send back an unknown program error for async messages,
we will confuse the client because they only expect replies
for method calls. Just log & drop any invalid async messages
* src/rpc/virnetserver.c: Don't send error for async messages
This patch annotates APIs with low or high priority.
In low set MUST be all APIs which might eventually access monitor
(and thus block indefinitely). Other APIs may be marked as high
priority. However, some must be (e.g. domainDestroy).
For high priority calls (HPC), there are some high priority workers
(HPW) created in the pool. HPW can execute only HPC, although normal
worker can process any call regardless priority. Therefore, only those
APIs which are guaranteed to end in reasonable small amount of time
can be marked as HPC.
The size of this HPC pool is static, because HPC are expected to end
quickly, therefore jobs assigned to this pool will be served quickly.
It can be configured in libvirtd.conf via prio_workers variable.
Default is set to 5.
To mark API with low or high priority, append priority:{low|high} to
it's comment in src/remote/remote_protocol.x. This is similar to
autogen|skipgen. If not marked, the generator assumes low as default.
Commit 2c85644b0b attempted to
fix a problem with tracking RPC messages from streams by doing
- if (msg->header.type == VIR_NET_REPLY) {
+ if (msg->header.type == VIR_NET_REPLY ||
+ (msg->header.type == VIR_NET_STREAM &&
+ msg->header.status != VIR_NET_CONTINUE)) {
client->nrequests--;
In other words any stream packet, with status NET_OK or NET_ERROR
would cause nrequests to be decremented. This is great if the
packet from from a synchronous virStreamFinish or virStreamAbort
API call, but wildly wrong if from a server initiated abort.
The latter resulted in 'nrequests' being decremented below zero.
This then causes all I/O for that client to be stopped.
Instead of trying to infer whether we need to decrement the
nrequests field, from the message type/status, introduce an
explicit 'bool tracked' field to mark whether the virNetMessagePtr
object is subject to tracking.
Also add a virNetMessageClear function to allow a message
contents to be cleared out, without adversely impacting the
'tracked' field as a naive memset() would do
* src/rpc/virnetmessage.c, src/rpc/virnetmessage.h: Add
a 'bool tracked' field and virNetMessageClear() API
* daemon/remote.c, daemon/stream.c, src/rpc/virnetclientprogram.c,
src/rpc/virnetclientstream.c, src/rpc/virnetserverclient.c,
src/rpc/virnetserverprogram.c: Switch over to use
virNetMessageClear() and pass in the 'bool tracked' value
when creating messages.
The bufferOffset has been initialized to zero in virNetMessageEncodePayloadRaw(),
so, we use bufferLength to represent the length of message which is going to be
sent to client side.
In case we add a new program in the future (we did that in the past and
we are going to do it again soon) current daemon will behave badly with
new client that wants to use the new program. Before the RPC rewrite we
used to just send an error reply to any request with unknown program.
With the RPC rewrite in 0.9.3 the daemon just closes the connection
through which such request was sent. This patch fixes this regression.
If a stream gets a server initiated abort, the client may still
send an abort request before it receives the server side abort.
This causes the server to send back another abort for the
stream. Since the protocol defines that abort is the last thing
to be sent, the client gets confused by this second abort from
the server. If the stream is already shutdown, just drop any
client requested abort, rather than sending back another message.
This fixes the regression from previous versions.
Tested as follows
In one virsh session
virsh # start foo
virsh # console foo
In other virsh session
virsh # destroy foo
The first virsh session should be able to continue issuing
commands without error. Prior to this patch it saw
virsh # list
error: Failed to list active domains
error: An error occurred, but the cause is unknown
virsh # list
error: Failed to list active domains
error: no call waiting for reply with prog 536903814 vers 1 serial 9
* src/rpc/virnetserverprogram.c: Drop abort requests
for streams which no longer exist
We ignore any stream data packets which come in for streams which
are not registered, since these packets are async and do not have
a reply. If we get a stream control packet though we must send back
an actual error, otherwise a (broken) client may hang forever
making it hard to diagnose the client bug.
* src/rpc/virnetserverprogram.c: Send back error for unexpected
stream control messages
If a message packet for a invalid stream is received it is just
free'd. This is not good because it doesn't let the client RPC
request counter decrement. If a stream is shutdown with pending
packets the message also isn't released properly because of an
incorrect header type
* daemon/stream.c: Fix message header type
* src/rpc/virnetserverprogram.c: Send dummy reply instead of
free'ing ignored stream message
On stream completion it is neccessary to send back a
message with an empty payload. The message header was
not being filled out correctly, since we were not writing
any payload. Add a method for encoding an empty payload
which updates the message headers correctly.
* src/rpc/virnetmessage.c, src/rpc/virnetmessage.h: Add
a virNetMessageEncodePayloadEmpty method
* src/rpc/virnetserverprogram.c: Write empty payload on
stream completion
To facilitate creation of new daemons providing XDR RPC services,
pull a lot of the libvirtd daemon code into a set of reusable
objects.
* virNetServer: A server contains one or more services which
accept incoming clients. It maintains the list of active
clients. It has a list of RPC programs which can be used
by clients. When clients produce a complete RPC message,
the server passes this onto the corresponding program for
handling, and queues any response back with the client.
* virNetServerClient: Encapsulates a single client connection.
All I/O for the client is handled, reading & writing RPC
messages.
* virNetServerProgram: Handles processing and dispatch of
RPC method calls for a single RPC (program,version).
Multiple programs can be registered with the server.
* virNetServerService: Encapsulates socket(s) listening for
new connections. Each service listens on a single host/port,
but may have multiple sockets if on a dual IPv4/6 host.
Each new daemon now merely has to define the list of RPC procedures
& their handlers. It does not need to deal with any network related
functionality at all.
