This commit introduces a vhost-user-scsi backend sample application. It
must be linked with libiscsi and libvhost-user.

To use it, compile with:
  $ make vhost-user-scsi

And run as follows:
  $ ./vhost-user-scsi -u vus.sock -i iscsi://uri_to_target/
  $ qemu-system-x86_64 --enable-kvm -m 512 \
      -object memory-backend-file,id=mem,size=512m,share=on,mem-path=guestmem \
      -numa node,memdev=mem \
      -chardev socket,id=vhost-user-scsi,path=vus.sock \
      -device vhost-user-scsi-pci,chardev=vhost-user-scsi \

The application is currently limited at one LUN only and it processes
requests synchronously (therefore only achieving QD1). The purpose of
the code is to show how a backend can be implemented and to test the
vhost-user-scsi Qemu implementation.

If a different instance of this vhost-user-scsi application is executed
at a remote host, a VM can be live migrated to such a host.
Signed-off-by: NFelipe Franciosi <felipe@nutanix.com>
Message-Id: <1488479153-21203-5-git-send-email-felipe@nutanix.com>

This commit introduces a vhost-user device for SCSI. This is based
on the existing vhost-scsi implementation, but done over vhost-user
instead. It also uses a chardev to connect to the backend. Unlike
vhost-scsi (today), VMs using vhost-user-scsi can be live migrated.

To use it, start Qemu with a command line equivalent to:

qemu-system-x86_64 \
       -chardev socket,id=vus0,path=/tmp/vus.sock \
       -device vhost-user-scsi-pci,chardev=vus0,bus=pci.0,addr=...

A separate commit presents a sample application linked with libiscsi to
provide a backend for vhost-user-scsi.
Signed-off-by: NFelipe Franciosi <felipe@nutanix.com>
Message-Id: <1488479153-21203-4-git-send-email-felipe@nutanix.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This is for the future interoperability & management guide.  It includes
the QAPI docs, including the automatically generated ones, other socket
protocols (vhost-user, VNC), and the qcow2 file format.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

These are defined in config-target.h and thus should never be
used in common code.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1497468113-2874-3-git-send-email-thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Since we've got some new CPU targets in QEMU during the last months
and years, we've got some new TARGET_xxx defines now which should
be marked as poisoned for common code.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1497468113-2874-2-git-send-email-thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

- do not use 'goto error_reply' outside a switch to jump into the
  middle of the switch's default case label
- reduce code duplication
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-13-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

For consistency use 'ret' name for saving return code everywhere
in the file.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-12-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

"goto fail" error handling scheme is not needed for just returning
error code. Better is return it immediately.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-11-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Current code will return 0 on this nbd_write fail, as rc is 0
after successful nbd_negotiate_options. Fix this.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-10-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

"co" field of NBDClientNewData has never been used, all the way back to
its declaration in commit 1a6245a5. So let's just use client pointer
instead of extra structure.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-9-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Move function tail, about receiving next request out of the function.
Error path is simplified and nbd_co_receive_request becomes more
corresponding to its name.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-8-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

For now nbd_read never returns EAGAIN. So, don't handle it.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-7-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

As nbd_write never returns value > 0, we can get rid of extra ret.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-6-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Now nbd_read and friends return int, so get rid of ssize_t.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-5-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Functions nbd_negotiate_{read,write,drop_sync} were introduced in
1a6245a5, when nbd_rwv (was nbd_wr_sync) was working through
qemu_co_sendv_recvv (the path is nbd_wr_sync -> qemu_co_{recv/send} ->
qemu_co_send_recv -> qemu_co_sendv_recvv), which just yields, without
setting any handlers. But starting from ff82911c nbd_rwv (was
nbd_wr_syncv) works through qio_channel_yield() which sets handlers, so
watchers are redundant in nbd_negotiate_{read,write,drop_sync}, then,
let's just use nbd_{read,write,drop} functions.

Functions nbd_{read,write,drop} has errp parameter, which is unused in
this patch. This will be fixed later.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170602150150.258222-4-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Following commit will reuse it for nbd server too.
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20170602150150.258222-3-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Rename
  nbd_wr_syncv -> nbd_rwv
  read_sync -> nbd_read
  read_sync_eof -> nbd_read_eof
  write_sync -> nbd_write
  drop_sync -> nbd_drop

1. nbd_ prefix
   read_sync and write_sync are already shared, so it is good to have a
   namespace prefix. drop_sync will be shared, and read_sync_eof is
   related to read_sync, so let's rename them all.

2. _sync suffix
   _sync is related to the fact that nbd_wr_syncv doesn't return if a
   write to socket returns EAGAIN. The first implementation of
   nbd_wr_syncv (was wr_sync in 7a5ca864) just loops while getting
   EAGAIN, the current implementation yields in this case.
   Why we want to get rid of it:
   - it is normal for r/w functions to be synchronous, so having an
     additional suffix for it looks redundant (contrariwise, we have
     _aio suffix for async functions)
   - _sync suffix in block layer is used when function does flush (so
     using it for other thing is confusing a bit)
   - keep function names short after adding nbd_ prefix

3. for nbd_wr_syncv let's use more common notation 'rw'
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20170602150150.258222-2-vsementsov@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

move kvm related accelerator files into accel/ subdirectory, also
create one stub subdirectory, which will include accelerator's stub
files.
Signed-off-by: NYang Zhong <yang.zhong@intel.com>
Message-Id: <1496383606-18060-5-git-send-email-yang.zhong@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

move tcg-runtime.c, translate-all.(ch) and translate-common.c into
accel/tcg/ subdirectory and updated related trace-events file.
Signed-off-by: NYang Zhong <yang.zhong@intel.com>
Message-Id: <1496383606-18060-4-git-send-email-yang.zhong@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

move cputlb.c, cpu-exec-common.c and cpu-exec.c related tcg exec
file into accel/tcg/ subdirectory.
Signed-off-by: NYang Zhong <yang.zhong@intel.com>
Message-Id: <1496383606-18060-3-git-send-email-yang.zhong@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

there are some types of accelerators in qemu, and all accelerators
have their own file except tcg. tcg accelerator is also defined in
accel.c file. tcg accelerator file will be splited from accel.c and
re-name to tcg-all.c. accel/ directory will be created to include
kvm and tcg related files.
Signed-off-by: NYang Zhong <yang.zhong@intel.com>
Message-Id: <1496383606-18060-2-git-send-email-yang.zhong@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

qemu proper has done so for 13 years
(8a7ddc38), qemu-img and qemu-io have
done so for four years (526eda14).
Ignoring this signal is especially important in qemu-nbd because
otherwise a client can easily take down the qemu-nbd server by dropping
the connection when the server wants to send something, for example:

$ qemu-nbd -x foo -f raw -t null-co:// &
[1] 12726
$ qemu-io -c quit nbd://localhost/bar
can't open device nbd://localhost/bar: No export with name 'bar' available
[1]  + 12726 broken pipe  qemu-nbd -x foo -f raw -t null-co://

In this case, the client sends an NBD_OPT_ABORT and closes the
connection (because it is not required to wait for a reply), but the
server replies with an NBD_REP_ACK (because it is required to reply).
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20170611123714.31292-1-mreitz@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Back in qemu 2.5, qemu-nbd was immune to port probes (a transient
server would not quit, regardless of how many probe connections
came and went, until a connection actually negotiated).  But we
broke that in commit ee7d7aab when removing the return value to
nbd_client_new(), although that patch also introduced a bug causing
an assertion failure on a client that fails negotiation.  We then
made it worse during refactoring in commit 1a6245a5 (a segfault
before we could even assert); the (masked) assertion was cleaned
up in d3780c2d (still in 2.6), and just recently we finally fixed
the segfault ("nbd: Fully intialize client in case of failed
negotiation").  But that still means that ever since we added
TLS support to qemu-nbd, we have been vulnerable to an ill-timed
port-scan being able to cause a denial of service by taking down
qemu-nbd before a real client has a chance to connect.

Since negotiation is now handled asynchronously via coroutines,
we no longer have a synchronous point of return by re-adding a
return value to nbd_client_new().  So this patch instead wires
things up to pass the negotiation status through the close_fn
callback function.

Simple test across two terminals:
$ qemu-nbd -f raw -p 30001 file
$ nmap 127.0.0.1 -p 30001 && \
  qemu-io -c 'r 0 512' -f raw nbd://localhost:30001

Note that this patch does not change what constitutes successful
negotiation (thus, a client must enter transmission phase before
that client can be considered as a reason to terminate the server
when the connection ends).  Perhaps we may want to tweak things
in a later patch to also treat a client that uses NBD_OPT_ABORT
as being a 'successful' negotiation (the client correctly talked
the NBD protocol, and informed us it was not going to use our
export after all), but that's a discussion for another day.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1451614Signed-off-by: NEric Blake <eblake@redhat.com>
Message-Id: <20170608222617.20376-1-eblake@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

While at it, drop the current_cpu assignment since this is a
per-thread variable on modern QEMU.

Cc: Vincent Palatin <vpalatin@chromium.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Wrap the bulk of kvm_cpu_exec with cpu_exec_start/end, so that kvm
version can also enjoy performing certain operations while all vCPUs are
quiescent.
Signed-off-by: NRoman Kagan <rkagan@virtuozzo.com>
Message-Id: <20170606181948.16238-15-rkagan@virtuozzo.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Commit bde4d920 ("Fix the -accel parameter and the documentation for
'hax'") introduced a regression by adding a new local accel_opts
variable which shadows the variable with the same name that is
declared at the beginning of the main() scope. This causes the
qemu_tcg_configure() call later to be always called with NULL, so
that the thread=xxx option gets ignored. Fix it by removing the
local accel_opts variable and use "opts" instead, which is meant
for storing temporary QemuOpts values.
And while we're at it, also change the exit(1) here to exit(0)
since asking for help is not an error.

Fixes: bde4d920Reported-by: NMarkus Armbruster <armbru@redhat.com>
Reported-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1496899257-25800-1-git-send-email-thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When doing a "make -j10" in the vanilla QEMU source tree (without
running "configure" first), the Makefile currently generates two
files already, qemu-version.h and qemu-options.def. This should not
happen, so let's only build the generated files if config-host.mak
is available (i.e. "configure" has been run already).
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1496926799-13040-1-git-send-email-thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This ensures that the request is unref'ed properly, and avoids a
segmentation fault in the new qtest testcase that is added.
This is CVE-2017-9503.
Reported-by: NZhangyanyu <zyy4013@stu.ouc.edu.cn>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Avoid TOC-TOU bugs by passing the frame_cmd down, and checking
cmd->dcmd_opcode instead of cmd->frame->header.frame_cmd.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Avoid TOC-TOU bugs by storing the DCMD opcode in the MegasasCmd
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Avoid TOC-TOU bugs depending on how the compiler behaves.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Avoid TOC-TOU bugs depending on how the compiler behaves.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Now unnecessary since ivshmem uses memory_region_init_ram_from_fd.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170602141229.15326-7-marcandre.lureau@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Instead of having its own mmap handling code, reuse the code from
exec.c.

Note: memory_region_init_ram_from_fd() adds some restrictions
(check for xen, kvm sync-mmu, etc) and changes (such as size
alignment). This may actually be more correct.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170602141229.15326-6-marcandre.lureau@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add a new function to initialize a RAM memory region with a file
descriptor to be mmap-ed.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170602141229.15326-5-marcandre.lureau@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add qemu_ram_alloc_from_fd(), which can be use to allocate ramblock from
fd only.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170602141229.15326-4-marcandre.lureau@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Move file opening part in a seperate function, file_ram_open(). This
allows for reuse of file_ram_alloc() with a given fd.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170602141229.15326-3-marcandre.lureau@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>