Original Xbox Emulator for Windows, macOS, and Linux (Active Development)
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Eric Blake 3fa4c76590 nbd: Merge nbd_export_set_name into nbd_export_new
The existing NBD code had a weird split where nbd_export_new()
created an export but did not add it to the list of exported
names until a later nbd_export_set_name() came along and grabbed
a second reference on the object; later, the first call to
nbd_export_close() drops the second reference while removing
the export from the list.  This is in part because the QAPI
NbdServerRemoveNode enum documents the possibility of adding a
mode where we could do a soft disconnect: preventing new clients,
but waiting for existing clients to gracefully quit, based on
the mode used when calling nbd_export_close().

But in spite of all that, note that we never change the name of
an NBD export while it is exposed, which means it is easier to
just inline the process of setting the name as part of creating
the export.

Inline the contents of nbd_export_set_name() and
nbd_export_set_description() into the two points in an export
lifecycle where they matter, then adjust both callers to pass
the name up front.  Note that for creation, all callers pass a
non-NULL name, (passing NULL at creation was for old style
servers, but we removed support for that in commit 7f7dfe2a),
so we can add an assert and do things unconditionally; but for
cleanup, because of the dual nature of nbd_export_close(), we
still have to be careful to avoid use-after-free.  Along the
way, add a comment reminding ourselves of the potential of
adding a middle mode disconnect.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20190111194720.15671-5-eblake@redhat.com>
2019-01-14 10:09:46 -06:00
accel qemu/queue.h: leave head structs anonymous unless necessary 2019-01-11 15:46:55 +01:00
audio audio/alsaaudio: Remove compiler check around pragma 2018-12-12 10:01:13 +01:00
backends hostmem: use object id for memory region name with >= 4.0 2019-01-07 16:18:42 +04:00
block block/dirty-bitmap: remove assertion from restore 2019-01-14 10:09:46 -06:00
bsd-user avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
capstone@22ead3e0bf disas: Add capstone as submodule 2017-10-26 11:56:20 +02:00
chardev configure: bump spice-server required version to 0.12.5 2019-01-10 08:55:13 +01:00
contrib avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
crypto remove space-tab sequences 2019-01-11 15:46:55 +01:00
default-configs default-configs: Enable USB support for RISC-V machines 2019-01-09 17:34:10 -08:00
disas remove space-tab sequences 2019-01-11 15:46:55 +01:00
docs nbd: Document timeline of various features 2019-01-04 17:41:28 -06:00
dtc@88f18909db Update dtc/libfdt submodule to v1.4.7 2018-10-02 13:53:26 +10:00
fpu hardfloat: implement float32/64 comparison 2018-12-17 08:25:25 +00:00
fsdev qemu/queue.h: leave head structs anonymous unless necessary 2019-01-11 15:46:55 +01:00
gdb-xml s390x/gdb: add gs registers 2017-07-14 12:29:49 +02:00
hw vga: enable virtio test, fix ddc oob read 2019-01-11 19:09:14 +00:00
include nbd: Merge nbd_export_set_name into nbd_export_new 2019-01-14 10:09:46 -06:00
io io: return 0 for EOF in TLS session read after shutdown 2018-11-19 11:16:46 -06:00
libdecnumber build: remove CONFIG_LIBDECNUMBER 2017-10-16 18:03:52 +02:00
linux-headers linux-headers: update to 4.20-rc1 2018-10-19 13:44:11 +02:00
linux-user avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
migration qemu/queue.h: leave head structs anonymous unless necessary 2019-01-11 15:46:55 +01:00
nbd nbd: Merge nbd_export_set_name into nbd_export_new 2019-01-14 10:09:46 -06:00
net avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
pc-bios ui: bugfixes, drop keymap include support, drop dead code. 2019-01-10 16:29:02 +00:00
po po/Makefile: Modern shell scripting (use $() instead of ``) 2018-10-24 07:39:10 +01:00
qapi block: remove 'x' prefix from experimental bitmap APIs 2019-01-14 10:09:46 -06:00
qga qemu/queue.h: simplify reverse access to QTAILQ 2019-01-11 15:46:55 +01:00
qobject json: Fix to reject duplicate object member names 2018-12-13 19:20:11 +01:00
qom qom: Don't keep error value between object_property_parse() calls 2019-01-10 12:25:15 -02:00
replay replay: Exit on errors reading from replay log 2018-11-08 13:24:35 +00:00
roms roms: seabios: Rename CROSS_COMPILE to CROSS_PREFIX 2019-01-11 12:46:07 +01:00
scripts scripts: add script to convert multiline comments into 4-line format 2019-01-11 15:46:55 +01:00
scsi file-posix: Switch to .bdrv_co_ioctl 2018-12-14 11:52:41 +01:00
slirp remove space-tab sequences 2019-01-11 15:46:55 +01:00
stubs Error reporting patches for 2018-10-22 2018-10-23 17:20:23 +01:00
target RISC-V Updates for 3.2, Part 2 2019-01-14 11:41:43 +00:00
tcg avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
tests nbd: Only require disabled bitmap for read-only exports 2019-01-14 10:09:46 -06:00
trace trace: simple style changes 2018-12-12 10:04:59 +00:00
ui input: avoid malloc for mouse events 2019-01-14 11:04:35 +00:00
util avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
.dir-locals.el Add .dir-locals.el file to configure emacs coding style 2015-10-08 19:46:01 +03:00
.editorconfig editorconfig: set emacs mode 2018-11-01 12:13:12 +04:00
.exrc
.gdbinit .gdbinit: load QEMU sub-commands when gdb starts 2017-06-07 14:38:45 +01:00
.gitignore qapi: Reduce Makefile boilerplate 2018-12-11 18:28:46 +01:00
.gitmodules gitmodules: use 'https://' instead of 'git://' 2018-11-12 11:26:02 +00:00
.gitpublish Add a git-publish configuration file 2018-03-05 09:03:17 +00:00
.mailmap maint: Grammar fix to mailmap 2018-12-11 18:35:54 +01:00
.shippable.yml .shippable.yml: disable the win cross tests 2018-12-17 13:02:12 +00:00
.travis.yml .travis.yml: split MacOSX builds and reduce target list 2018-11-14 10:20:23 +00:00
arch_init.c arch_init: sort architectures 2018-06-01 19:20:38 +03:00
balloon.c balloon: Allow multiple inhibit users 2018-08-17 09:27:15 -06:00
block.c block: Assert that flags are up-to-date in bdrv_reopen_prepare() 2018-12-14 11:55:02 +01:00
blockdev-nbd.c nbd: Merge nbd_export_set_name into nbd_export_new 2019-01-14 10:09:46 -06:00
blockdev.c block: remove 'x' prefix from experimental bitmap APIs 2019-01-14 10:09:46 -06:00
blockjob.c block: Use a single global AioWait 2018-09-25 15:50:15 +02:00
bootdevice.c fw_cfg: ignore suffixes in the bootdevice list dependent on machine class 2018-08-16 22:27:43 -03:00
bt-host.c all: Clean up includes 2016-02-04 17:41:30 +00:00
bt-vhci.c all: Clean up includes 2016-02-04 17:41:30 +00:00
Changelog Use HTTPS for qemu.org and other domains 2017-11-21 13:34:13 +00:00
CODING_STYLE CODING_STYLE: Define our preferred form for multiline comments 2018-06-15 15:23:34 +01:00
configure Work around test-qht-par + gprof issues 2019-01-14 10:11:36 +00:00
COPYING
COPYING.LIB
cpus-common.c qemu/queue.h: simplify reverse access to QTAILQ 2019-01-11 15:46:55 +01:00
cpus.c cpus.c: Fix race condition in cpu_stop_current() 2019-01-07 15:23:47 +00:00
device_tree.c device_tree.c: Don't use load_image() 2018-12-14 13:30:52 +00:00
device-hotplug.c blockdev: Convert drive_new() to Error 2018-10-19 14:51:34 +02:00
disas.c disas: Add RISC-V support 2018-12-26 06:40:02 +11:00
dma-helpers.c block: explicitly acquire aiocontext in bottom halves that need it 2017-02-21 11:39:39 +00:00
dump.c qemu/queue.h: simplify reverse access to QTAILQ 2019-01-11 15:46:55 +01:00
exec.c qemu/queue.h: typedef QTAILQ heads 2019-01-11 15:46:55 +01:00
gdbstub.c gdbstub: add multiprocess extension support 2019-01-07 15:23:46 +00:00
gitdm.config contrib: add a basic gitdm config 2018-12-17 08:25:10 +00:00
HACKING HACKING: document preference for g_new instead of g_malloc 2018-05-20 08:32:09 +03:00
hmp-commands-info.hx hmp-commands-info: add sync-profile 2018-08-23 18:46:25 +02:00
hmp-commands.hx Deprecate HMP cpu-add 2018-12-11 15:45:22 -02:00
hmp.c qmp hmp: Make system_wakeup check wake-up support and run state 2018-12-18 07:55:47 +01:00
hmp.h hmp-commands: add sync-profile 2018-08-23 18:46:25 +02:00
ioport.c trace: switch to modular code generation for sub-directories 2017-01-31 17:11:18 +00:00
iothread.c iothread: fix crash with invalid properties 2018-10-12 09:46:14 +08:00
job-qmp.c jobs: canonize Error object 2018-08-31 16:28:33 +02:00
job.c job: Fix off-by-one assert checks for JobSTT and JobVerbTable 2018-11-12 17:49:21 +01:00
LICENSE vfio: move hw/misc/vfio.c to hw/vfio/pci.c Move vfio.h into include/hw/vfio 2014-12-19 15:24:06 -07:00
MAINTAINERS MAINTAINERS: add qemu_vga.ndrv file entry for Mac machines 2019-01-09 09:28:14 +11:00
Makefile keymaps: remove common include 2019-01-10 08:55:28 +01:00
Makefile.objs hw/gpio/nrf51_gpio: Add nRF51 GPIO peripheral 2019-01-07 15:23:47 +00:00
Makefile.target configure: Remove old -fno-gcse workaround for GCC 4.6.x and 4.7.[012] 2018-12-12 10:01:12 +01:00
memory_ldst.inc.c exec: Fix MAP_RAM for cached access 2018-06-28 19:05:30 +02:00
memory_mapping.c qemu/queue.h: simplify reverse access to QTAILQ 2019-01-11 15:46:55 +01:00
memory.c qemu/queue.h: simplify reverse access to QTAILQ 2019-01-11 15:46:55 +01:00
module-common.c all: Clean up includes 2016-02-04 17:41:30 +00:00
monitor.c qemu/queue.h: leave head structs anonymous unless necessary 2019-01-11 15:46:55 +01:00
numa.c numa: Clean up error reporting in parse_numa() 2018-10-19 14:51:34 +02:00
os-posix.c util: add qemu_write_pidfile() 2018-10-02 18:47:55 +02:00
os-win32.c util: add qemu_write_pidfile() 2018-10-02 18:47:55 +02:00
qdev-monitor.c qdev-monitor: Make device options help nicer 2018-11-05 15:18:04 +01:00
qdict-test-data.txt
qemu-bridge-helper.c all: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
qemu-deprecated.texi Mention that QMP 'cpu-add' will be deprecated 2019-01-09 22:09:31 -02:00
qemu-doc.texi doc: replace x-root with rootdir for usb-mtp 2018-10-01 10:49:54 +02:00
qemu-edid.c display/edid: add edid generator to qemu. 2018-09-27 08:07:51 +02:00
qemu-ga.texi qemu-ga: Remove stray 'q' in documentation 2016-10-28 18:17:23 +03:00
qemu-img-cmds.hx qemu-img: Add -C option for convert with copy offloading 2018-07-30 15:35:37 +02:00
qemu-img.c qemu-img: Fix leak 2018-11-21 15:17:46 +01:00
qemu-img.texi qemu-img: Add -C option for convert with copy offloading 2018-07-30 15:35:37 +02:00
qemu-io-cmds.c block: Remove flags parameter from bdrv_reopen_queue() 2018-12-14 11:55:02 +01:00
qemu-io.c qom: Clean up error reporting in user_creatable_add_opts_foreach() 2018-10-19 14:51:34 +02:00
qemu-keymap.c ui: use enum to string helpers 2018-08-24 08:40:10 +02:00
qemu-nbd.c nbd: Merge nbd_export_set_name into nbd_export_new 2019-01-14 10:09:46 -06:00
qemu-nbd.texi nbd: Add qemu-nbd -D for human-readable description 2016-11-02 09:28:55 +01:00
qemu-option-trace.texi qemu-option-trace: -trace enable= is a pattern, not a file 2018-05-20 08:29:01 +03:00
qemu-options-wrapper.h qemu-img: remove references to GEN_DOCS 2018-05-20 08:35:54 +03:00
qemu-options.h Clean up ill-advised or unusual header guards 2016-07-12 16:20:46 +02:00
qemu-options.hx util: Implement debug-threads for macOS 2019-01-08 12:34:46 +00:00
qemu-seccomp.c seccomp: Clean up error reporting in parse_sandbox() 2018-10-19 14:51:34 +02:00
qemu-tech.texi cli qmp: Mark --preconfig, exit-preconfig experimental 2018-07-16 15:38:19 +02:00
qemu.nsi Use HTTPS for qemu.org and other domains 2017-11-21 13:34:13 +00:00
qemu.sasl Default to GSSAPI (Kerberos) instead of DIGEST-MD5 for SASL 2017-05-09 14:41:47 +01:00
qmp.c qmp hmp: Make system_wakeup check wake-up support and run state 2018-12-18 07:55:47 +01:00
qtest.c avoid TABs in files that only contain a few 2019-01-11 15:46:56 +01:00
README README: use 'https://' instead of 'git://' 2018-11-12 11:26:02 +00:00
replication.c replication: Introduce new APIs to do replication operation 2016-09-13 11:00:56 +01:00
replication.h block/replication: Remove protocol_name field 2018-03-26 12:16:00 +02:00
rules.mak test: replace gtester with a TAP driver 2019-01-11 15:46:52 +01:00
thunk.c thunk: assert nb_fields is valid 2017-07-31 13:06:39 +03:00
tpm.c tpm: Clean up error reporting in tpm_init_tpmdev() 2018-10-19 14:51:34 +02:00
trace-events jobs: remove ret argument to job_completed; privatize it 2018-08-31 16:28:33 +02:00
VERSION Open 4.0 development tree 2018-12-11 17:27:58 +00:00
version.rc Use HTTPS for qemu.org and other domains 2017-11-21 13:34:13 +00:00
vl.c qemu/queue.h: leave head structs anonymous unless necessary 2019-01-11 15:46:55 +01:00
win_dump.c dump: fix Windows dump memory run mapping 2018-10-02 18:47:55 +02:00
win_dump.h dump: move Windows dump structures definitions 2018-10-02 19:09:12 +02:00

         QEMU README
         ===========

QEMU is a generic and open source machine & userspace emulator and
virtualizer.

QEMU is capable of emulating a complete machine in software without any
need for hardware virtualization support. By using dynamic translation,
it achieves very good performance. QEMU can also integrate with the Xen
and KVM hypervisors to provide emulated hardware while allowing the
hypervisor to manage the CPU. With hypervisor support, QEMU can achieve
near native performance for CPUs. When QEMU emulates CPUs directly it is
capable of running operating systems made for one machine (e.g. an ARMv7
board) on a different machine (e.g. an x86_64 PC board).

QEMU is also capable of providing userspace API virtualization for Linux
and BSD kernel interfaces. This allows binaries compiled against one
architecture ABI (e.g. the Linux PPC64 ABI) to be run on a host using a
different architecture ABI (e.g. the Linux x86_64 ABI). This does not
involve any hardware emulation, simply CPU and syscall emulation.

QEMU aims to fit into a variety of use cases. It can be invoked directly
by users wishing to have full control over its behaviour and settings.
It also aims to facilitate integration into higher level management
layers, by providing a stable command line interface and monitor API.
It is commonly invoked indirectly via the libvirt library when using
open source applications such as oVirt, OpenStack and virt-manager.

QEMU as a whole is released under the GNU General Public License,
version 2. For full licensing details, consult the LICENSE file.


Building
========

QEMU is multi-platform software intended to be buildable on all modern
Linux platforms, OS-X, Win32 (via the Mingw64 toolchain) and a variety
of other UNIX targets. The simple steps to build QEMU are:

  mkdir build
  cd build
  ../configure
  make

Additional information can also be found online via the QEMU website:

  https://qemu.org/Hosts/Linux
  https://qemu.org/Hosts/Mac
  https://qemu.org/Hosts/W32


Submitting patches
==================

The QEMU source code is maintained under the GIT version control system.

   git clone https://git.qemu.org/git/qemu.git

When submitting patches, one common approach is to use 'git
format-patch' and/or 'git send-email' to format & send the mail to the
qemu-devel@nongnu.org mailing list. All patches submitted must contain
a 'Signed-off-by' line from the author. Patches should follow the
guidelines set out in the HACKING and CODING_STYLE files.

Additional information on submitting patches can be found online via
the QEMU website

  https://qemu.org/Contribute/SubmitAPatch
  https://qemu.org/Contribute/TrivialPatches

The QEMU website is also maintained under source control.

  git clone https://git.qemu.org/git/qemu-web.git
  https://www.qemu.org/2017/02/04/the-new-qemu-website-is-up/

A 'git-publish' utility was created to make above process less
cumbersome, and is highly recommended for making regular contributions,
or even just for sending consecutive patch series revisions. It also
requires a working 'git send-email' setup, and by default doesn't
automate everything, so you may want to go through the above steps
manually for once.

For installation instructions, please go to

  https://github.com/stefanha/git-publish

The workflow with 'git-publish' is:

  $ git checkout master -b my-feature
  $ # work on new commits, add your 'Signed-off-by' lines to each
  $ git publish

Your patch series will be sent and tagged as my-feature-v1 if you need to refer
back to it in the future.

Sending v2:

  $ git checkout my-feature # same topic branch
  $ # making changes to the commits (using 'git rebase', for example)
  $ git publish

Your patch series will be sent with 'v2' tag in the subject and the git tip
will be tagged as my-feature-v2.

Bug reporting
=============

The QEMU project uses Launchpad as its primary upstream bug tracker. Bugs
found when running code built from QEMU git or upstream released sources
should be reported via:

  https://bugs.launchpad.net/qemu/

If using QEMU via an operating system vendor pre-built binary package, it
is preferable to report bugs to the vendor's own bug tracker first. If
the bug is also known to affect latest upstream code, it can also be
reported via launchpad.

For additional information on bug reporting consult:

  https://qemu.org/Contribute/ReportABug


Contact
=======

The QEMU community can be contacted in a number of ways, with the two
main methods being email and IRC

 - qemu-devel@nongnu.org
   https://lists.nongnu.org/mailman/listinfo/qemu-devel
 - #qemu on irc.oftc.net

Information on additional methods of contacting the community can be
found online via the QEMU website:

  https://qemu.org/Contribute/StartHere

-- End