Adding upstream version 18.2.2.upstream/18.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

22 files changed, 3387 insertions, 0 deletions

diff --git a/src/liburing/.gitignore b/src/liburing/.gitignore
new file mode 100644
index 000000000..5faee05b7
--- /dev/null
+++ b/src/liburing/.gitignore
@@ -0,0 +1,103 @@
+*.rej
+*.orig
+*~
+/*.patch
+
+*.o
+*.o[ls]
+
+/src/liburing.a
+/src/liburing.so*
+/src/include/liburing/compat.h
+
+/examples/io_uring-cp
+/examples/io_uring-test
+/examples/link-cp
+/examples/ucontext-cp
+
+/test/232c93d07b74-test
+/test/35fa71a030ca-test
+/test/500f9fbadef8-test
+/test/7ad0e4b2f83c-test
+/test/8a9973408177-test
+/test/917257daa0fe-test
+/test/a0908ae19763-test
+/test/a4c0b3decb33-test
+/test/accept
+/test/accept-link
+/test/accept-reuse
+/test/accept-test
+/test/across-fork
+/test/b19062a56726-test
+/test/b5837bd5311d-test
+/test/ce593a6c480a-test
+/test/connect
+/test/close-opath
+/test/cq-full
+/test/cq-overflow
+/test/cq-peek-batch
+/test/cq-ready
+/test/cq-size
+/test/d4ae271dfaae-test
+/test/d77a67ed5f27-test
+/test/defer
+/test/eeed8b54e0df-test
+/test/eventfd
+/test/eventfd-disable
+/test/eventfd-ring
+/test/fadvise
+/test/fallocate
+/test/fc2a85cb02ef-test
+/test/file-register
+/test/file-update
+/test/fixed-link
+/test/fsync
+/test/io_uring_enter
+/test/io_uring_register
+/test/io_uring_setup
+/test/io-cancel
+/test/lfs-openat
+/test/lfs-openat-write
+/test/link
+/test/link-timeout
+/test/link_drain
+/test/madvise
+/test/nop
+/test/open-close
+/test/openat2
+/test/personality
+/test/poll
+/test/poll-cancel
+/test/poll-cancel-ton
+/test/poll-link
+/test/poll-many
+/test/poll-v-poll
+/test/probe
+/test/read-write
+/test/ring-leak
+/test/send_recv
+/test/send_recvmsg
+/test/shared-wq
+/test/short-read
+/test/socket-rw
+/test/splice
+/test/sq-full
+/test/sq-full-cpp
+/test/sq-poll-kthread
+/test/sq-space_left
+/test/statx
+/test/stdout
+/test/submit-reuse
+/test/teardowns
+/test/timeout
+/test/timeout-overflow
+/test/iopoll
+/test/cq-overflow-peek
+/test/config.local
+/test/*.dmesg
+
+config-host.h
+config-host.mak
+config.log
+
+liburing.pc
diff --git a/src/liburing/.travis.yml b/src/liburing/.travis.yml
new file mode 100644
index 000000000..e02fdd033
--- /dev/null
+++ b/src/liburing/.travis.yml
@@ -0,0 +1,22 @@
+language: cpp
+os:
+  - linux
+compiler:
+  - clang
+  - gcc
+env:
+  matrix:
+    - BUILD_ARCH="x86"
+    - BUILD_ARCH="x86_64"
+  global:
+    - MAKEFLAGS="-j 2"
+matrix:
+  exclude:
+    - os: linux
+      compiler: clang
+      env: BUILD_ARCH="x86" # Only do the gcc x86 build to reduce clutter
+before_install:
+  - EXTRA_CFLAGS="-Werror"
+script:
+  - ./configure && make
+  - sudo make runtests || true
diff --git a/src/liburing/COPYING b/src/liburing/COPYING
new file mode 100644
index 000000000..e5ab03e12
--- /dev/null
+++ b/src/liburing/COPYING
@@ -0,0 +1,502 @@
+                  GNU LESSER GENERAL PUBLIC LICENSE
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+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the library, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James Random Hacker.
+
+  <signature of Ty Coon>, 1 April 1990
+  Ty Coon, President of Vice
+
+That's all there is to it!
diff --git a/src/liburing/COPYING.GPL b/src/liburing/COPYING.GPL
new file mode 100644
index 000000000..d159169d1
--- /dev/null
+++ b/src/liburing/COPYING.GPL
@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
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+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
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+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
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+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
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+    an offer, in accord with Subsection b above.)
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+The source code for a work means the preferred form of the work for
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+distribution of the source code, even though third parties are not
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+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
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+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
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+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
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+through that system in reliance on consistent application of that
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+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+                            NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.
diff --git a/src/liburing/LICENSE b/src/liburing/LICENSE
new file mode 100644
index 000000000..ae941fa62
--- /dev/null
+++ b/src/liburing/LICENSE
@@ -0,0 +1,7 @@
+Copyright 2020 Jens Axboe
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/src/liburing/Makefile b/src/liburing/Makefile
new file mode 100644
index 000000000..948e00494
--- /dev/null
+++ b/src/liburing/Makefile
@@ -0,0 +1,77 @@
+NAME=liburing
+SPECFILE=$(NAME).spec
+VERSION=$(shell awk '/Version:/ { print $$2 }' $(SPECFILE))
+TAG = $(NAME)-$(VERSION)
+RPMBUILD=$(shell `which rpmbuild >&/dev/null` && echo "rpmbuild" || echo "rpm")
+
+INSTALL=install
+
+default: all
+
+all:
+	@$(MAKE) -C src
+	@$(MAKE) -C test
+	@$(MAKE) -C examples
+
+partcheck: all
+	@echo "make partcheck => TODO add tests with out kernel support"
+
+runtests: all
+	@$(MAKE) -C test runtests
+runtests-loop:
+	@$(MAKE) -C test runtests-loop
+
+config-host.mak: configure
+	@if [ ! -e "$@" ]; then					\
+	  echo "Running configure ...";				\
+	  ./configure;						\
+	else							\
+	  echo "$@ is out-of-date, running configure";		\
+	  sed -n "/.*Configured with/s/[^:]*: //p" "$@" | sh;	\
+	fi
+
+ifneq ($(MAKECMDGOALS),clean)
+include config-host.mak
+endif
+
+%.pc: %.pc.in config-host.mak $(SPECFILE)
+	sed -e "s%@prefix@%$(prefix)%g" \
+	    -e "s%@libdir@%$(libdir)%g" \
+	    -e "s%@includedir@%$(includedir)%g" \
+	    -e "s%@NAME@%$(NAME)%g" \
+	    -e "s%@VERSION@%$(VERSION)%g" \
+	    $< >$@
+
+install: $(NAME).pc
+	@$(MAKE) -C src install prefix=$(DESTDIR)$(prefix) \
+		includedir=$(DESTDIR)$(includedir) \
+		libdir=$(DESTDIR)$(libdir) \
+		libdevdir=$(DESTDIR)$(libdevdir) \
+		relativelibdir=$(relativelibdir)
+	$(INSTALL) -D -m 644 $(NAME).pc $(DESTDIR)$(libdevdir)/pkgconfig/$(NAME).pc
+	$(INSTALL) -m 755 -d $(DESTDIR)$(mandir)/man2
+	$(INSTALL) -m 644 man/*.2 $(DESTDIR)$(mandir)/man2
+
+install-tests:
+	@$(MAKE) -C test install prefix=$(DESTDIR)$(prefix) datadir=$(DESTDIR)$(datadir)
+
+clean:
+	@rm -f config-host.mak config-host.h cscope.out $(NAME).pc test/*.dmesg
+	@$(MAKE) -C src clean
+	@$(MAKE) -C test clean
+	@$(MAKE) -C examples clean
+
+cscope:
+	@cscope -b -R
+
+tag-archive:
+	@git tag $(TAG)
+
+create-archive:
+	@git archive --prefix=$(NAME)-$(VERSION)/ -o $(NAME)-$(VERSION).tar.gz $(TAG)
+	@echo "The final archive is ./$(NAME)-$(VERSION).tar.gz."
+
+archive: clean tag-archive create-archive
+
+srpm: create-archive
+	$(RPMBUILD) --define "_sourcedir `pwd`" --define "_srcrpmdir `pwd`" --nodeps -bs $(SPECFILE)
diff --git a/src/liburing/Makefile.quiet b/src/liburing/Makefile.quiet
new file mode 100644
index 000000000..8eac349a8
--- /dev/null
+++ b/src/liburing/Makefile.quiet
@@ -0,0 +1,10 @@
+ifneq ($(findstring $(MAKEFLAGS),s),s)
+ifndef V
+	QUIET_CC	= @echo '    '   CC $@;
+	QUIET_LINK	= @echo '  '   LINK $@;
+	QUIET_AR	= @echo '    '   AR $@;
+	QUIET_RANLIB	= @echo '' RANLIB $@;
+endif
+endif
+
+
diff --git a/src/liburing/README b/src/liburing/README
new file mode 100644
index 000000000..a76021ef4
--- /dev/null
+++ b/src/liburing/README
@@ -0,0 +1,46 @@
+liburing
+--------
+
+This is the io_uring library, liburing. liburing provides helpers to setup and
+teardown io_uring instances, and also a simplified interface for
+applications that don't need (or want) to deal with the full kernel
+side implementation.
+
+For more info on io_uring, please see:
+
+https://kernel.dk/io_uring.pdf
+
+Subscribe to io-uring@vger.kernel.org for io_uring related discussions
+and development for both kernel and userspace. The list is archived here:
+
+https://lore.kernel.org/io-uring/
+
+
+ulimit settings
+---------------
+
+io_uring accounts memory it needs under the rlimit memlocked option, which
+can be quite low on some setups (64K). The default is usually enough for
+most use cases, but bigger rings or things like registered buffers deplete
+it quickly. root isn't under this restriction, but regular users are. Going
+into detail on how to bump the limit on various systems is beyond the scope
+of this little blurb, but check /etc/security/limits.conf for user specific
+settings, or /etc/systemd/user.conf and /etc/systemd/system.conf for systemd
+setups.
+
+Regressions tests
+-----------------
+
+The bulk of liburing is actually regression/unit tests for both liburing and
+the kernel io_uring support. Please note that this suite isn't expected to
+pass on older kernels, and may even crash or hang older kernels!
+
+License
+-------
+
+All software contained within this repo is dual licensed LGPL and MIT, see
+COPYING and LICENSE, except for a header coming from the kernel which is
+dual licensed GPL with a Linux-syscall-note exception and MIT, see
+COPYING.GPL and <https://spdx.org/licenses/Linux-syscall-note.html>.
+
+Jens Axboe 2020-01-20
diff --git a/src/liburing/configure b/src/liburing/configure
new file mode 100755
index 000000000..518a5b03e
--- /dev/null
+++ b/src/liburing/configure
@@ -0,0 +1,368 @@
+#!/bin/sh
+#
+# set temporary file name
+if test ! -z "$TMPDIR" ; then
+    TMPDIR1="${TMPDIR}"
+elif test ! -z "$TEMPDIR" ; then
+    TMPDIR1="${TEMPDIR}"
+else
+    TMPDIR1="/tmp"
+fi
+
+cc=${CC:-gcc}
+cxx=${CXX:-g++}
+
+for opt do
+  optarg=$(expr "x$opt" : 'x[^=]*=\(.*\)')
+  case "$opt" in
+  --help|-h) show_help=yes
+  ;;
+  --prefix=*) prefix="$optarg"
+  ;;
+  --includedir=*) includedir="$optarg"
+  ;;
+  --libdir=*) libdir="$optarg"
+  ;;
+  --libdevdir=*) libdevdir="$optarg"
+  ;;
+  --mandir=*) mandir="$optarg"
+  ;;
+  --datadir=*) datadir="$optarg"
+  ;;
+  --cc=*) cc="$optarg"
+  ;;
+  --cxx=*) cxx="$optarg"
+  ;;
+  *)
+    echo "ERROR: unknown option $opt"
+    echo "Try '$0 --help' for more information"
+    exit 1
+  ;;
+  esac
+done
+
+if test -z "$prefix"; then
+  prefix=/usr
+fi
+if test -z "$includedir"; then
+  includedir="$prefix/include"
+fi
+if test -z "$libdir"; then
+  libdir="$prefix/lib"
+fi
+if test -z "$libdevdir"; then
+  libdevdir="$prefix/lib"
+fi
+if test -z "$mandir"; then
+  mandir="$prefix/man"
+fi
+if test -z "$datadir"; then
+  datadir="$prefix/share"
+fi
+
+if test x"$libdir" = x"$libdevdir"; then
+  relativelibdir=""
+else
+  relativelibdir="$libdir/"
+fi
+
+if test "$show_help" = "yes"; then
+cat <<EOF
+
+Usage: configure [options]
+Options: [defaults in brackets after descriptions]
+  --help                   print this message
+  --prefix=PATH            install in PATH [$prefix]
+  --includedir=PATH        install headers in PATH [$includedir]
+  --libdir=PATH            install runtime libraries in PATH [$libdir]
+  --libdevdir=PATH         install development libraries in PATH [$libdevdir]
+  --mandir=PATH            install man pages in PATH [$mandir]
+  --datadir=PATH           install shared data in PATH [$datadir]
+EOF
+exit 0
+fi
+
+TMPC="${TMPDIR1}/fio-conf-${RANDOM}-$$-${RANDOM}.c"
+TMPC2="${TMPDIR1}/fio-conf-${RANDOM}-$$-${RANDOM}-2.c"
+TMPO="${TMPDIR1}/fio-conf-${RANDOM}-$$-${RANDOM}.o"
+TMPE="${TMPDIR1}/fio-conf-${RANDOM}-$$-${RANDOM}.exe"
+
+# NB: do not call "exit" in the trap handler; this is buggy with some shells;
+# see <1285349658-3122-1-git-send-email-loic.minier@linaro.org>
+trap "rm -f $TMPC $TMPC2 $TMPO $TMPE" EXIT INT QUIT TERM
+
+rm -rf config.log
+
+config_host_mak="config-host.mak"
+config_host_h="config-host.h"
+
+rm -rf $config_host_mak
+rm -rf $config_host_h
+
+fatal() {
+  echo $@
+  echo "Configure failed, check config.log and/or the above output"
+  rm -rf $config_host_mak
+  rm -rf $config_host_h
+  exit 1
+}
+
+# Print result for each configuration test
+print_config() {
+  printf "%-30s%s\n" "$1" "$2"
+}
+
+# Default CFLAGS
+CFLAGS="-D_GNU_SOURCE -include config-host.h"
+BUILD_CFLAGS=""
+
+# Print configure header at the top of $config_host_h
+echo "/*" > $config_host_h
+echo " * Automatically generated by configure - do not modify" >> $config_host_h
+printf " * Configured with:" >> $config_host_h
+printf " * '%s'" "$0" "$@" >> $config_host_h
+echo "" >> $config_host_h
+echo " */" >> $config_host_h
+
+echo "# Automatically generated by configure - do not modify" > $config_host_mak
+printf "# Configured with:" >> $config_host_mak
+printf " '%s'" "$0" "$@" >> $config_host_mak
+echo >> $config_host_mak
+
+do_cxx() {
+    # Run the compiler, capturing its output to the log.
+    echo $cxx "$@" >> config.log
+    $cxx "$@" >> config.log 2>&1 || return $?
+    return 0
+}
+
+do_cc() {
+    # Run the compiler, capturing its output to the log.
+    echo $cc "$@" >> config.log
+    $cc "$@" >> config.log 2>&1 || return $?
+    # Test passed. If this is an --enable-werror build, rerun
+    # the test with -Werror and bail out if it fails. This
+    # makes warning-generating-errors in configure test code
+    # obvious to developers.
+    if test "$werror" != "yes"; then
+        return 0
+    fi
+    # Don't bother rerunning the compile if we were already using -Werror
+    case "$*" in
+        *-Werror*)
+           return 0
+        ;;
+    esac
+    echo $cc -Werror "$@" >> config.log
+    $cc -Werror "$@" >> config.log 2>&1 && return $?
+    echo "ERROR: configure test passed without -Werror but failed with -Werror."
+    echo "This is probably a bug in the configure script. The failing command"
+    echo "will be at the bottom of config.log."
+    fatal "You can run configure with --disable-werror to bypass this check."
+}
+
+compile_prog() {
+  local_cflags="$1"
+  local_ldflags="$2 $LIBS"
+  echo "Compiling test case $3" >> config.log
+  do_cc $CFLAGS $local_cflags -o $TMPE $TMPC $LDFLAGS $local_ldflags
+}
+
+compile_prog_cxx() {
+  local_cflags="$1"
+  local_ldflags="$2 $LIBS"
+  echo "Compiling test case $3" >> config.log
+  do_cxx $CFLAGS $local_cflags -o $TMPE $TMPC $LDFLAGS $local_ldflags
+}
+
+has() {
+  type "$1" >/dev/null 2>&1
+}
+
+output_mak() {
+  echo "$1=$2" >> $config_host_mak
+}
+
+output_sym() {
+  output_mak "$1" "y"
+  echo "#define $1" >> $config_host_h
+}
+
+print_and_output_mak() {
+  print_config "$1" "$2"
+  output_mak "$1" "$2"
+}
+print_and_output_mak "prefix" "$prefix"
+print_and_output_mak "includedir" "$includedir"
+print_and_output_mak "libdir" "$libdir"
+print_and_output_mak "libdevdir" "$libdevdir"
+print_and_output_mak "relativelibdir" "$relativelibdir"
+print_and_output_mak "mandir" "$mandir"
+print_and_output_mak "datadir" "$datadir"
+
+##########################################
+# check for __kernel_rwf_t
+__kernel_rwf_t="no"
+cat > $TMPC << EOF
+#include <linux/fs.h>
+int main(int argc, char **argv)
+{
+  __kernel_rwf_t x;
+  x = 0;
+  return x;
+}
+EOF
+if compile_prog "" "" "__kernel_rwf_t"; then
+  __kernel_rwf_t="yes"
+fi
+print_config "__kernel_rwf_t" "$__kernel_rwf_t"
+
+##########################################
+# check for __kernel_timespec
+__kernel_timespec="no"
+cat > $TMPC << EOF
+#include <linux/time.h>
+#include <linux/time_types.h>
+int main(int argc, char **argv)
+{
+  struct __kernel_timespec ts;
+  ts.tv_sec = 0;
+  ts.tv_nsec = 1;
+  return 0;
+}
+EOF
+if compile_prog "" "" "__kernel_timespec"; then
+  __kernel_timespec="yes"
+fi
+print_config "__kernel_timespec" "$__kernel_timespec"
+
+##########################################
+# check for open_how
+open_how="no"
+cat > $TMPC << EOF
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+int main(int argc, char **argv)
+{
+  struct open_how how;
+  how.flags = 0;
+  how.mode = 0;
+  how.resolve = 0;
+  return 0;
+}
+EOF
+if compile_prog "" "" "open_how"; then
+  open_how="yes"
+fi
+print_config "open_how" "$open_how"
+
+##########################################
+# check for statx
+statx="no"
+cat > $TMPC << EOF
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <linux/stat.h>
+int main(int argc, char **argv)
+{
+  struct statx x;
+
+  return memset(&x, 0, sizeof(x)) != NULL;
+}
+EOF
+if compile_prog "" "" "statx"; then
+  statx="yes"
+fi
+print_config "statx" "$statx"
+
+##########################################
+# check for C++
+has_cxx="no"
+cat > $TMPC << EOF
+#include <iostream>
+int main(int argc, char **argv)
+{
+  std::cout << "Test";
+  return 0;
+}
+EOF
+if compile_prog_cxx "" "" "C++"; then
+  has_cxx="yes"
+fi
+print_config "C++" "$has_cxx"
+
+#############################################################################
+
+if test "$__kernel_rwf_t" = "yes"; then
+  output_sym "CONFIG_HAVE_KERNEL_RWF_T"
+fi
+if test "$__kernel_timespec" = "yes"; then
+  output_sym "CONFIG_HAVE_KERNEL_TIMESPEC"
+fi
+if test "$open_how" = "yes"; then
+  output_sym "CONFIG_HAVE_OPEN_HOW"
+fi
+if test "$statx" = "yes"; then
+  output_sym "CONFIG_HAVE_STATX"
+fi
+if test "$has_cxx" = "yes"; then
+  output_sym "CONFIG_HAVE_CXX"
+fi
+
+echo "CC=$cc" >> $config_host_mak
+print_config "CC" "$cc"
+echo "CXX=$cxx" >> $config_host_mak
+print_config "CXX" "$cxx"
+
+# generate compat.h
+compat_h="src/include/liburing/compat.h"
+cat > $compat_h << EOF
+/* SPDX-License-Identifier: MIT */
+#ifndef LIBURING_COMPAT_H
+#define LIBURING_COMPAT_H
+
+EOF
+
+if test "$__kernel_rwf_t" != "yes"; then
+cat >> $compat_h << EOF
+typedef int __kernel_rwf_t;
+
+EOF
+fi
+if test "$__kernel_timespec" != "yes"; then
+cat >> $compat_h << EOF
+#include <stdint.h>
+
+struct __kernel_timespec {
+	int64_t		tv_sec;
+	long long	tv_nsec;
+};
+
+EOF
+else
+cat >> $compat_h << EOF
+#include <linux/time_types.h>
+
+EOF
+fi
+if test "$open_how" != "yes"; then
+cat >> $compat_h << EOF
+#include <inttypes.h>
+
+struct open_how {
+	uint64_t	flags;
+	uint64_t	mode;
+	uint64_t	resolve;
+};
+
+EOF
+fi
+
+cat >> $compat_h << EOF
+#endif
+EOF
diff --git a/src/liburing/liburing.pc.in b/src/liburing/liburing.pc.in
new file mode 100644
index 000000000..e621939ef
--- /dev/null
+++ b/src/liburing/liburing.pc.in
@@ -0,0 +1,12 @@
+prefix=@prefix@
+exec_prefix=${prefix}
+libdir=@libdir@
+includedir=@includedir@
+
+Name: @NAME@
+Version: @VERSION@
+Description: io_uring library
+URL: http://git.kernel.dk/cgit/liburing/
+
+Libs: -L${libdir} -luring
+Cflags: -I${includedir}
diff --git a/src/liburing/liburing.spec b/src/liburing/liburing.spec
new file mode 100644
index 000000000..bfe46bdcd
--- /dev/null
+++ b/src/liburing/liburing.spec
@@ -0,0 +1,63 @@
+Name: liburing
+Version: 0.7
+Release: 1%{?dist}
+Summary: Linux-native io_uring I/O access library
+License: (GPLv2 with exceptions and LGPLv2+) or MIT
+Source0: https://brick.kernel.dk/snaps/%{name}-%{version}.tar.gz
+Source1: https://brick.kernel.dk/snaps/%{name}-%{version}.tar.gz.asc
+URL: https://git.kernel.dk/cgit/liburing/
+BuildRequires: gcc
+
+%description
+Provides native async IO for the Linux kernel, in a fast and efficient
+manner, for both buffered and O_DIRECT.
+
+%package devel
+Summary: Development files for Linux-native io_uring I/O access library
+Requires: %{name}%{_isa} = %{version}-%{release}
+Requires: pkgconfig
+
+%description devel
+This package provides header files to include and libraries to link with
+for the Linux-native io_uring.
+
+%prep
+%autosetup
+
+%build
+%set_build_flags
+./configure --prefix=%{_prefix} --libdir=/%{_libdir} --libdevdir=/%{_libdir} --mandir=%{_mandir} --includedir=%{_includedir}
+
+%make_build
+
+%install
+%make_install
+
+%files
+%attr(0755,root,root) %{_libdir}/liburing.so.*
+%license COPYING
+
+%files devel
+%{_includedir}/liburing/
+%{_includedir}/liburing.h
+%{_libdir}/liburing.so
+%exclude %{_libdir}/liburing.a
+%{_libdir}/pkgconfig/*
+%{_mandir}/man2/*
+
+%changelog
+* Thu Oct 31 2019 Jeff Moyer <jmoyer@redhat.com> - 0.2-1
+- Add io_uring_cq_ready()
+- Add io_uring_peek_batch_cqe()
+- Add io_uring_prep_accept()
+- Add io_uring_prep_{recv,send}msg()
+- Add io_uring_prep_timeout_remove()
+- Add io_uring_queue_init_params()
+- Add io_uring_register_files_update()
+- Add io_uring_sq_space_left()
+- Add io_uring_wait_cqe_timeout()
+- Add io_uring_wait_cqes()
+- Add io_uring_wait_cqes_timeout()
+
+* Tue Jan 8 2019 Jens Axboe <axboe@kernel.dk> - 0.1
+- Initial version
diff --git a/src/liburing/make-debs.sh b/src/liburing/make-debs.sh
new file mode 100755
index 000000000..01d563cda
--- /dev/null
+++ b/src/liburing/make-debs.sh
@@ -0,0 +1,53 @@
+#!/usr/bin/env bash
+# Copyright (C) 2019  Liu Changcheng <changcheng.liu@aliyun.com>
+# Author: Liu Changcheng <changcheng.liu@aliyun.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+set -xe
+
+# Create dir for build
+base=${1:-/tmp/release}
+codename=$(lsb_release -sc)
+releasedir=$base/$(lsb_release -si)/liburing
+rm -rf $releasedir
+mkdir -p $releasedir
+
+src_dir=$(readlink -e `basename $0`)
+liburing_dir=$(dirname $src_dir)
+basename=$(basename $liburing_dir)
+dirname=$(dirname $liburing_dir)
+version=$(git describe --match "lib*" | cut -d '-' -f 2)
+outfile="liburing-$version"
+orgfile=$(echo $outfile | tr '-' '_')
+
+# Prepare source code
+cp -arf ${dirname}/${basename} ${releasedir}/${outfile}
+cd ${releasedir}/${outfile}
+git clean -dxf
+
+# Change changelog if it's needed
+cur_ver=`head -l debian/changelog | sed -n -e 's/.* (\(.*\)) .*/\1/p'`
+if [ "$cur_ver" != "$version-1" ]; then
+	dch -D $codename --force-distribution -b -v "$version-1" "new version"
+fi
+
+# Create tar archieve
+cd ../
+tar cvzf ${outfile}.tar.gz ${outfile}
+ln -s ${outfile}.tar.gz ${orgfile}.orig.tar.gz
+
+# Build debian package
+cd -
+debuild
diff --git a/src/liburing/src/Makefile b/src/liburing/src/Makefile
new file mode 100644
index 000000000..44a95ad78
--- /dev/null
+++ b/src/liburing/src/Makefile
@@ -0,0 +1,73 @@
+prefix ?= /usr
+includedir ?= $(prefix)/include
+libdir ?= $(prefix)/lib
+libdevdir ?= $(prefix)/lib
+
+CFLAGS ?= -g -fomit-frame-pointer -O2
+override CFLAGS += -Wall -Wextra -Wno-unused-parameter -Wno-sign-compare\
+	-Iinclude/ -include ../config-host.h
+SO_CFLAGS=-fPIC $(CFLAGS)
+L_CFLAGS=$(CFLAGS)
+LINK_FLAGS=
+LINK_FLAGS+=$(LDFLAGS)
+ENABLE_SHARED ?= 1
+
+soname=liburing.so.1
+minor=0
+micro=7
+libname=$(soname).$(minor).$(micro)
+all_targets += liburing.a
+
+ifeq ($(ENABLE_SHARED),1)
+all_targets += $(libname)
+endif
+
+include ../Makefile.quiet
+
+ifneq ($(MAKECMDGOALS),clean)
+include ../config-host.mak
+endif
+
+all: $(all_targets)
+
+liburing_srcs := setup.c queue.c syscall.c register.c
+
+liburing_objs := $(patsubst %.c,%.ol,$(liburing_srcs))
+liburing_sobjs := $(patsubst %.c,%.os,$(liburing_srcs))
+
+$(liburing_objs) $(liburing_sobjs): include/liburing/io_uring.h
+
+%.os: %.c
+	$(QUIET_CC)$(CC) $(SO_CFLAGS) -c -o $@ $<
+
+%.ol: %.c
+	$(QUIET_CC)$(CC) $(L_CFLAGS) -c -o $@ $<
+
+AR ?= ar
+RANLIB ?= ranlib
+liburing.a: $(liburing_objs)
+	@rm -f liburing.a
+	$(QUIET_AR)$(AR) r liburing.a $^
+	$(QUIET_RANLIB)$(RANLIB) liburing.a
+
+$(libname): $(liburing_sobjs) liburing.map
+	$(QUIET_CC)$(CC) $(SO_CFLAGS) -shared -Wl,--version-script=liburing.map -Wl,-soname=$(soname) -o $@ $(liburing_sobjs) $(LINK_FLAGS)
+
+install: $(all_targets)
+	install -D -m 644 include/liburing/io_uring.h $(includedir)/liburing/io_uring.h
+	install -D -m 644 include/liburing.h $(includedir)/liburing.h
+	install -D -m 644 include/liburing/compat.h $(includedir)/liburing/compat.h
+	install -D -m 644 include/liburing/barrier.h $(includedir)/liburing/barrier.h
+	install -D -m 644 liburing.a $(libdevdir)/liburing.a
+ifeq ($(ENABLE_SHARED),1)
+	install -D -m 755 $(libname) $(libdir)/$(libname)
+	ln -sf $(libname) $(libdir)/$(soname)
+	ln -sf $(relativelibdir)$(libname) $(libdevdir)/liburing.so
+endif
+
+$(liburing_objs): include/liburing.h
+
+clean:
+	@rm -f $(all_targets) $(liburing_objs) $(liburing_sobjs) $(soname).new
+	@rm -f *.so* *.a *.o
+	@rm -f include/liburing/compat.h
diff --git a/src/liburing/src/include/liburing.h b/src/liburing/src/include/liburing.h
new file mode 100644
index 000000000..0505a4f50
--- /dev/null
+++ b/src/liburing/src/include/liburing.h
@@ -0,0 +1,521 @@
+/* SPDX-License-Identifier: MIT */
+#ifndef LIB_URING_H
+#define LIB_URING_H
+
+#include <sys/socket.h>
+#include <sys/uio.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <inttypes.h>
+#include <time.h>
+#include <linux/swab.h>
+#include "liburing/compat.h"
+#include "liburing/io_uring.h"
+#include "liburing/barrier.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Library interface to io_uring
+ */
+struct io_uring_sq {
+	unsigned *khead;
+	unsigned *ktail;
+	unsigned *kring_mask;
+	unsigned *kring_entries;
+	unsigned *kflags;
+	unsigned *kdropped;
+	unsigned *array;
+	struct io_uring_sqe *sqes;
+
+	unsigned sqe_head;
+	unsigned sqe_tail;
+
+	size_t ring_sz;
+	void *ring_ptr;
+};
+
+struct io_uring_cq {
+	unsigned *khead;
+	unsigned *ktail;
+	unsigned *kring_mask;
+	unsigned *kring_entries;
+	unsigned *kflags;
+	unsigned *koverflow;
+	struct io_uring_cqe *cqes;
+
+	size_t ring_sz;
+	void *ring_ptr;
+};
+
+struct io_uring {
+	struct io_uring_sq sq;
+	struct io_uring_cq cq;
+	unsigned flags;
+	int ring_fd;
+};
+
+/*
+ * Library interface
+ */
+
+/*
+ * return an allocated io_uring_probe structure, or NULL if probe fails (for
+ * example, if it is not available). The caller is responsible for freeing it
+ */
+extern struct io_uring_probe *io_uring_get_probe_ring(struct io_uring *ring);
+/* same as io_uring_get_probe_ring, but takes care of ring init and teardown */
+extern struct io_uring_probe *io_uring_get_probe(void);
+
+static inline int io_uring_opcode_supported(struct io_uring_probe *p, int op)
+{
+	if (op > p->last_op)
+		return 0;
+	return (p->ops[op].flags & IO_URING_OP_SUPPORTED) != 0;
+}
+
+extern int io_uring_queue_init_params(unsigned entries, struct io_uring *ring,
+	struct io_uring_params *p);
+extern int io_uring_queue_init(unsigned entries, struct io_uring *ring,
+	unsigned flags);
+extern int io_uring_queue_mmap(int fd, struct io_uring_params *p,
+	struct io_uring *ring);
+extern int io_uring_ring_dontfork(struct io_uring *ring);
+extern void io_uring_queue_exit(struct io_uring *ring);
+unsigned io_uring_peek_batch_cqe(struct io_uring *ring,
+	struct io_uring_cqe **cqes, unsigned count);
+extern int io_uring_wait_cqes(struct io_uring *ring,
+	struct io_uring_cqe **cqe_ptr, unsigned wait_nr,
+	struct __kernel_timespec *ts, sigset_t *sigmask);
+extern int io_uring_wait_cqe_timeout(struct io_uring *ring,
+	struct io_uring_cqe **cqe_ptr, struct __kernel_timespec *ts);
+extern int io_uring_submit(struct io_uring *ring);
+extern int io_uring_submit_and_wait(struct io_uring *ring, unsigned wait_nr);
+extern struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring);
+
+extern int io_uring_register_buffers(struct io_uring *ring,
+					const struct iovec *iovecs,
+					unsigned nr_iovecs);
+extern int io_uring_unregister_buffers(struct io_uring *ring);
+extern int io_uring_register_files(struct io_uring *ring, const int *files,
+					unsigned nr_files);
+extern int io_uring_unregister_files(struct io_uring *ring);
+extern int io_uring_register_files_update(struct io_uring *ring, unsigned off,
+					int *files, unsigned nr_files);
+extern int io_uring_register_eventfd(struct io_uring *ring, int fd);
+extern int io_uring_register_eventfd_async(struct io_uring *ring, int fd);
+extern int io_uring_unregister_eventfd(struct io_uring *ring);
+extern int io_uring_register_probe(struct io_uring *ring,
+					struct io_uring_probe *p, unsigned nr);
+extern int io_uring_register_personality(struct io_uring *ring);
+extern int io_uring_unregister_personality(struct io_uring *ring, int id);
+
+/*
+ * Helper for the peek/wait single cqe functions. Exported because of that,
+ * but probably shouldn't be used directly in an application.
+ */
+extern int __io_uring_get_cqe(struct io_uring *ring,
+			      struct io_uring_cqe **cqe_ptr, unsigned submit,
+			      unsigned wait_nr, sigset_t *sigmask);
+
+#define LIBURING_UDATA_TIMEOUT	((__u64) -1)
+
+#define io_uring_for_each_cqe(ring, head, cqe)				\
+	/*								\
+	 * io_uring_smp_load_acquire() enforces the order of tail	\
+	 * and CQE reads.						\
+	 */								\
+	for (head = *(ring)->cq.khead;					\
+	     (cqe = (head != io_uring_smp_load_acquire((ring)->cq.ktail) ? \
+		&(ring)->cq.cqes[head & (*(ring)->cq.kring_mask)] : NULL)); \
+	     head++)							\
+
+/*
+ * Must be called after io_uring_for_each_cqe()
+ */
+static inline void io_uring_cq_advance(struct io_uring *ring,
+				       unsigned nr)
+{
+	if (nr) {
+		struct io_uring_cq *cq = &ring->cq;
+
+		/*
+		 * Ensure that the kernel only sees the new value of the head
+		 * index after the CQEs have been read.
+		 */
+		io_uring_smp_store_release(cq->khead, *cq->khead + nr);
+	}
+}
+
+/*
+ * Must be called after io_uring_{peek,wait}_cqe() after the cqe has
+ * been processed by the application.
+ */
+static inline void io_uring_cqe_seen(struct io_uring *ring,
+				     struct io_uring_cqe *cqe)
+{
+	if (cqe)
+		io_uring_cq_advance(ring, 1);
+}
+
+/*
+ * Command prep helpers
+ */
+static inline void io_uring_sqe_set_data(struct io_uring_sqe *sqe, void *data)
+{
+	sqe->user_data = (unsigned long) data;
+}
+
+static inline void *io_uring_cqe_get_data(const struct io_uring_cqe *cqe)
+{
+	return (void *) (uintptr_t) cqe->user_data;
+}
+
+static inline void io_uring_sqe_set_flags(struct io_uring_sqe *sqe,
+					  unsigned flags)
+{
+	sqe->flags = flags;
+}
+
+static inline void io_uring_prep_rw(int op, struct io_uring_sqe *sqe, int fd,
+				    const void *addr, unsigned len,
+				    __u64 offset)
+{
+	sqe->opcode = op;
+	sqe->flags = 0;
+	sqe->ioprio = 0;
+	sqe->fd = fd;
+	sqe->off = offset;
+	sqe->addr = (unsigned long) addr;
+	sqe->len = len;
+	sqe->rw_flags = 0;
+	sqe->user_data = 0;
+	sqe->__pad2[0] = sqe->__pad2[1] = sqe->__pad2[2] = 0;
+}
+
+static inline void io_uring_prep_splice(struct io_uring_sqe *sqe,
+					int fd_in, uint64_t off_in,
+					int fd_out, uint64_t off_out,
+					unsigned int nbytes,
+					unsigned int splice_flags)
+{
+	io_uring_prep_rw(IORING_OP_SPLICE, sqe, fd_out, NULL, nbytes, off_out);
+	sqe->splice_off_in = off_in;
+	sqe->splice_fd_in = fd_in;
+	sqe->splice_flags = splice_flags;
+}
+
+static inline void io_uring_prep_readv(struct io_uring_sqe *sqe, int fd,
+				       const struct iovec *iovecs,
+				       unsigned nr_vecs, off_t offset)
+{
+	io_uring_prep_rw(IORING_OP_READV, sqe, fd, iovecs, nr_vecs, offset);
+}
+
+static inline void io_uring_prep_read_fixed(struct io_uring_sqe *sqe, int fd,
+					    void *buf, unsigned nbytes,
+					    off_t offset, int buf_index)
+{
+	io_uring_prep_rw(IORING_OP_READ_FIXED, sqe, fd, buf, nbytes, offset);
+	sqe->buf_index = buf_index;
+}
+
+static inline void io_uring_prep_writev(struct io_uring_sqe *sqe, int fd,
+					const struct iovec *iovecs,
+					unsigned nr_vecs, off_t offset)
+{
+	io_uring_prep_rw(IORING_OP_WRITEV, sqe, fd, iovecs, nr_vecs, offset);
+}
+
+static inline void io_uring_prep_write_fixed(struct io_uring_sqe *sqe, int fd,
+					     const void *buf, unsigned nbytes,
+					     off_t offset, int buf_index)
+{
+	io_uring_prep_rw(IORING_OP_WRITE_FIXED, sqe, fd, buf, nbytes, offset);
+	sqe->buf_index = buf_index;
+}
+
+static inline void io_uring_prep_recvmsg(struct io_uring_sqe *sqe, int fd,
+					 struct msghdr *msg, unsigned flags)
+{
+	io_uring_prep_rw(IORING_OP_RECVMSG, sqe, fd, msg, 1, 0);
+	sqe->msg_flags = flags;
+}
+
+static inline void io_uring_prep_sendmsg(struct io_uring_sqe *sqe, int fd,
+					 const struct msghdr *msg, unsigned flags)
+{
+	io_uring_prep_rw(IORING_OP_SENDMSG, sqe, fd, msg, 1, 0);
+	sqe->msg_flags = flags;
+}
+
+static inline void io_uring_prep_poll_add(struct io_uring_sqe *sqe, int fd,
+					  unsigned poll_mask)
+{
+	io_uring_prep_rw(IORING_OP_POLL_ADD, sqe, fd, NULL, 0, 0);
+#if __BYTE_ORDER == __BIG_ENDIAN
+	poll_mask = __swahw32(poll_mask);
+#endif
+	sqe->poll32_events = poll_mask;
+}
+
+static inline void io_uring_prep_poll_remove(struct io_uring_sqe *sqe,
+					     void *user_data)
+{
+	io_uring_prep_rw(IORING_OP_POLL_REMOVE, sqe, -1, user_data, 0, 0);
+}
+
+static inline void io_uring_prep_fsync(struct io_uring_sqe *sqe, int fd,
+				       unsigned fsync_flags)
+{
+	io_uring_prep_rw(IORING_OP_FSYNC, sqe, fd, NULL, 0, 0);
+	sqe->fsync_flags = fsync_flags;
+}
+
+static inline void io_uring_prep_nop(struct io_uring_sqe *sqe)
+{
+	io_uring_prep_rw(IORING_OP_NOP, sqe, -1, NULL, 0, 0);
+}
+
+static inline void io_uring_prep_timeout(struct io_uring_sqe *sqe,
+					 struct __kernel_timespec *ts,
+					 unsigned count, unsigned flags)
+{
+	io_uring_prep_rw(IORING_OP_TIMEOUT, sqe, -1, ts, 1, count);
+	sqe->timeout_flags = flags;
+}
+
+static inline void io_uring_prep_timeout_remove(struct io_uring_sqe *sqe,
+						__u64 user_data, unsigned flags)
+{
+	io_uring_prep_rw(IORING_OP_TIMEOUT_REMOVE, sqe, -1,
+				(void *)(unsigned long)user_data, 0, 0);
+	sqe->timeout_flags = flags;
+}
+
+static inline void io_uring_prep_accept(struct io_uring_sqe *sqe, int fd,
+					struct sockaddr *addr,
+					socklen_t *addrlen, int flags)
+{
+	io_uring_prep_rw(IORING_OP_ACCEPT, sqe, fd, addr, 0,
+				(__u64) (unsigned long) addrlen);
+	sqe->accept_flags = flags;
+}
+
+static inline void io_uring_prep_cancel(struct io_uring_sqe *sqe, void *user_data,
+					int flags)
+{
+	io_uring_prep_rw(IORING_OP_ASYNC_CANCEL, sqe, -1, user_data, 0, 0);
+	sqe->cancel_flags = flags;
+}
+
+static inline void io_uring_prep_link_timeout(struct io_uring_sqe *sqe,
+					      struct __kernel_timespec *ts,
+					      unsigned flags)
+{
+	io_uring_prep_rw(IORING_OP_LINK_TIMEOUT, sqe, -1, ts, 1, 0);
+	sqe->timeout_flags = flags;
+}
+
+static inline void io_uring_prep_connect(struct io_uring_sqe *sqe, int fd,
+					 const struct sockaddr *addr,
+					 socklen_t addrlen)
+{
+	io_uring_prep_rw(IORING_OP_CONNECT, sqe, fd, addr, 0, addrlen);
+}
+
+static inline void io_uring_prep_files_update(struct io_uring_sqe *sqe,
+					      int *fds, unsigned nr_fds,
+					      int offset)
+{
+	io_uring_prep_rw(IORING_OP_FILES_UPDATE, sqe, -1, fds, nr_fds, offset);
+}
+
+static inline void io_uring_prep_fallocate(struct io_uring_sqe *sqe, int fd,
+					   int mode, off_t offset, off_t len)
+{
+
+	io_uring_prep_rw(IORING_OP_FALLOCATE, sqe, fd,
+			(const uintptr_t *) (unsigned long) len, mode, offset);
+}
+
+static inline void io_uring_prep_openat(struct io_uring_sqe *sqe, int dfd,
+					const char *path, int flags, mode_t mode)
+{
+	io_uring_prep_rw(IORING_OP_OPENAT, sqe, dfd, path, mode, 0);
+	sqe->open_flags = flags;
+}
+
+static inline void io_uring_prep_close(struct io_uring_sqe *sqe, int fd)
+{
+	io_uring_prep_rw(IORING_OP_CLOSE, sqe, fd, NULL, 0, 0);
+}
+
+static inline void io_uring_prep_read(struct io_uring_sqe *sqe, int fd,
+				      void *buf, unsigned nbytes, off_t offset)
+{
+	io_uring_prep_rw(IORING_OP_READ, sqe, fd, buf, nbytes, offset);
+}
+
+static inline void io_uring_prep_write(struct io_uring_sqe *sqe, int fd,
+				       const void *buf, unsigned nbytes, off_t offset)
+{
+	io_uring_prep_rw(IORING_OP_WRITE, sqe, fd, buf, nbytes, offset);
+}
+
+struct statx;
+static inline void io_uring_prep_statx(struct io_uring_sqe *sqe, int dfd,
+				const char *path, int flags, unsigned mask,
+				struct statx *statxbuf)
+{
+	io_uring_prep_rw(IORING_OP_STATX, sqe, dfd, path, mask,
+				(__u64) (unsigned long) statxbuf);
+	sqe->statx_flags = flags;
+}
+
+static inline void io_uring_prep_fadvise(struct io_uring_sqe *sqe, int fd,
+					 off_t offset, off_t len, int advice)
+{
+	io_uring_prep_rw(IORING_OP_FADVISE, sqe, fd, NULL, len, offset);
+	sqe->fadvise_advice = advice;
+}
+
+static inline void io_uring_prep_madvise(struct io_uring_sqe *sqe, void *addr,
+					 off_t length, int advice)
+{
+	io_uring_prep_rw(IORING_OP_MADVISE, sqe, -1, addr, length, 0);
+	sqe->fadvise_advice = advice;
+}
+
+static inline void io_uring_prep_send(struct io_uring_sqe *sqe, int sockfd,
+				      const void *buf, size_t len, int flags)
+{
+	io_uring_prep_rw(IORING_OP_SEND, sqe, sockfd, buf, len, 0);
+	sqe->msg_flags = flags;
+}
+
+static inline void io_uring_prep_recv(struct io_uring_sqe *sqe, int sockfd,
+				      void *buf, size_t len, int flags)
+{
+	io_uring_prep_rw(IORING_OP_RECV, sqe, sockfd, buf, len, 0);
+	sqe->msg_flags = flags;
+}
+
+static inline void io_uring_prep_openat2(struct io_uring_sqe *sqe, int dfd,
+					const char *path, struct open_how *how)
+{
+	io_uring_prep_rw(IORING_OP_OPENAT2, sqe, dfd, path, sizeof(*how),
+				(uint64_t) (uintptr_t) how);
+}
+
+struct epoll_event;
+static inline void io_uring_prep_epoll_ctl(struct io_uring_sqe *sqe, int epfd,
+					   int fd, int op,
+					   struct epoll_event *ev)
+{
+	io_uring_prep_rw(IORING_OP_EPOLL_CTL, sqe, epfd, ev, op, fd);
+}
+
+static inline void io_uring_prep_provide_buffers(struct io_uring_sqe *sqe,
+						 void *addr, int len, int nr,
+						 int bgid, int bid)
+{
+	io_uring_prep_rw(IORING_OP_PROVIDE_BUFFERS, sqe, nr, addr, len, bid);
+	sqe->buf_group = bgid;
+}
+
+static inline void io_uring_prep_remove_buffers(struct io_uring_sqe *sqe,
+						int nr, int bgid)
+{
+	io_uring_prep_rw(IORING_OP_REMOVE_BUFFERS, sqe, nr, NULL, 0, 0);
+	sqe->buf_group = bgid;
+}
+
+static inline unsigned io_uring_sq_ready(struct io_uring *ring)
+{
+	/* always use real head, to avoid losing sync for short submit */
+	return ring->sq.sqe_tail - *ring->sq.khead;
+}
+
+static inline unsigned io_uring_sq_space_left(struct io_uring *ring)
+{
+	return *ring->sq.kring_entries - io_uring_sq_ready(ring);
+}
+
+static inline unsigned io_uring_cq_ready(struct io_uring *ring)
+{
+	return io_uring_smp_load_acquire(ring->cq.ktail) - *ring->cq.khead;
+}
+
+static inline bool io_uring_cq_eventfd_enabled(struct io_uring *ring)
+{
+	if (!ring->cq.kflags)
+		return true;
+
+	return !(*ring->cq.kflags & IORING_CQ_EVENTFD_DISABLED);
+}
+
+static inline int io_uring_cq_eventfd_toggle(struct io_uring *ring,
+					     bool enabled)
+{
+	uint32_t flags;
+
+	if (!!enabled == io_uring_cq_eventfd_enabled(ring))
+		return 0;
+
+	if (!ring->cq.kflags)
+		return -EOPNOTSUPP;
+
+	flags = *ring->cq.kflags;
+
+	if (enabled)
+		flags &= ~IORING_CQ_EVENTFD_DISABLED;
+	else
+		flags |= IORING_CQ_EVENTFD_DISABLED;
+
+	IO_URING_WRITE_ONCE(*ring->cq.kflags, flags);
+
+	return 0;
+}
+
+/*
+ * Return an IO completion, waiting for 'wait_nr' completions if one isn't
+ * readily available. Returns 0 with cqe_ptr filled in on success, -errno on
+ * failure.
+ */
+static inline int io_uring_wait_cqe_nr(struct io_uring *ring,
+				      struct io_uring_cqe **cqe_ptr,
+				      unsigned wait_nr)
+{
+	return __io_uring_get_cqe(ring, cqe_ptr, 0, wait_nr, NULL);
+}
+
+/*
+ * Return an IO completion, if one is readily available. Returns 0 with
+ * cqe_ptr filled in on success, -errno on failure.
+ */
+static inline int io_uring_peek_cqe(struct io_uring *ring,
+				    struct io_uring_cqe **cqe_ptr)
+{
+	return io_uring_wait_cqe_nr(ring, cqe_ptr, 0);
+}
+
+/*
+ * Return an IO completion, waiting for it if necessary. Returns 0 with
+ * cqe_ptr filled in on success, -errno on failure.
+ */
+static inline int io_uring_wait_cqe(struct io_uring *ring,
+				    struct io_uring_cqe **cqe_ptr)
+{
+	return io_uring_wait_cqe_nr(ring, cqe_ptr, 1);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/src/liburing/src/include/liburing/barrier.h b/src/liburing/src/include/liburing/barrier.h
new file mode 100644
index 000000000..a4a59fb49
--- /dev/null
+++ b/src/liburing/src/include/liburing/barrier.h
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: MIT */
+#ifndef LIBURING_BARRIER_H
+#define LIBURING_BARRIER_H
+
+/*
+From the kernel documentation file refcount-vs-atomic.rst:
+
+A RELEASE memory ordering guarantees that all prior loads and
+stores (all po-earlier instructions) on the same CPU are completed
+before the operation. It also guarantees that all po-earlier
+stores on the same CPU and all propagated stores from other CPUs
+must propagate to all other CPUs before the release operation
+(A-cumulative property). This is implemented using
+:c:func:`smp_store_release`.
+
+An ACQUIRE memory ordering guarantees that all post loads and
+stores (all po-later instructions) on the same CPU are
+completed after the acquire operation. It also guarantees that all
+po-later stores on the same CPU must propagate to all other CPUs
+after the acquire operation executes. This is implemented using
+:c:func:`smp_acquire__after_ctrl_dep`.
+*/
+
+#ifdef __cplusplus
+#include <atomic>
+
+template <typename T>
+static inline void IO_URING_WRITE_ONCE(T &var, T val)
+{
+	std::atomic_store_explicit(reinterpret_cast<std::atomic<T> *>(&var),
+				   val, std::memory_order_relaxed);
+}
+template <typename T>
+static inline T IO_URING_READ_ONCE(const T &var)
+{
+	return std::atomic_load_explicit(
+		reinterpret_cast<const std::atomic<T> *>(&var),
+		std::memory_order_relaxed);
+}
+
+template <typename T>
+static inline void io_uring_smp_store_release(T *p, T v)
+{
+	std::atomic_store_explicit(reinterpret_cast<std::atomic<T> *>(p), v,
+				   std::memory_order_release);
+}
+
+template <typename T>
+static inline T io_uring_smp_load_acquire(const T *p)
+{
+	return std::atomic_load_explicit(
+		reinterpret_cast<const std::atomic<T> *>(p),
+		std::memory_order_acquire);
+}
+#else
+#include <stdatomic.h>
+
+#define IO_URING_WRITE_ONCE(var, val)				\
+	atomic_store_explicit((_Atomic typeof(var) *)&(var),	\
+			      (val), memory_order_relaxed)
+#define IO_URING_READ_ONCE(var)					\
+	atomic_load_explicit((_Atomic typeof(var) *)&(var),	\
+			     memory_order_relaxed)
+
+#define io_uring_smp_store_release(p, v)			\
+	atomic_store_explicit((_Atomic typeof(*(p)) *)(p), (v), \
+			      memory_order_release)
+#define io_uring_smp_load_acquire(p)				\
+	atomic_load_explicit((_Atomic typeof(*(p)) *)(p),	\
+			     memory_order_acquire)
+#endif
+
+#endif /* defined(LIBURING_BARRIER_H) */
diff --git a/src/liburing/src/include/liburing/io_uring.h b/src/liburing/src/include/liburing/io_uring.h
new file mode 100644
index 000000000..d39b45fdd
--- /dev/null
+++ b/src/liburing/src/include/liburing/io_uring.h
@@ -0,0 +1,301 @@
+/* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR MIT */
+/*
+ * Header file for the io_uring interface.
+ *
+ * Copyright (C) 2019 Jens Axboe
+ * Copyright (C) 2019 Christoph Hellwig
+ */
+#ifndef LINUX_IO_URING_H
+#define LINUX_IO_URING_H
+
+#include <linux/fs.h>
+#include <linux/types.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * IO submission data structure (Submission Queue Entry)
+ */
+struct io_uring_sqe {
+	__u8	opcode;		/* type of operation for this sqe */
+	__u8	flags;		/* IOSQE_ flags */
+	__u16	ioprio;		/* ioprio for the request */
+	__s32	fd;		/* file descriptor to do IO on */
+	union {
+		__u64	off;	/* offset into file */
+		__u64	addr2;
+	};
+	union {
+		__u64	addr;	/* pointer to buffer or iovecs */
+		__u64	splice_off_in;
+	};
+	__u32	len;		/* buffer size or number of iovecs */
+	union {
+		__kernel_rwf_t	rw_flags;
+		__u32		fsync_flags;
+		__u16		poll_events;	/* compatibility */
+		__u32		poll32_events;	/* word-reversed for BE */
+		__u32		sync_range_flags;
+		__u32		msg_flags;
+		__u32		timeout_flags;
+		__u32		accept_flags;
+		__u32		cancel_flags;
+		__u32		open_flags;
+		__u32		statx_flags;
+		__u32		fadvise_advice;
+		__u32		splice_flags;
+	};
+	__u64	user_data;	/* data to be passed back at completion time */
+	union {
+		struct {
+			/* pack this to avoid bogus arm OABI complaints */
+			union {
+				/* index into fixed buffers, if used */
+				__u16	buf_index;
+				/* for grouped buffer selection */
+				__u16	buf_group;
+			} __attribute__((packed));
+			/* personality to use, if used */
+			__u16	personality;
+			__s32	splice_fd_in;
+		};
+		__u64	__pad2[3];
+	};
+};
+
+enum {
+	IOSQE_FIXED_FILE_BIT,
+	IOSQE_IO_DRAIN_BIT,
+	IOSQE_IO_LINK_BIT,
+	IOSQE_IO_HARDLINK_BIT,
+	IOSQE_ASYNC_BIT,
+	IOSQE_BUFFER_SELECT_BIT,
+};
+
+/*
+ * sqe->flags
+ */
+/* use fixed fileset */
+#define IOSQE_FIXED_FILE	(1U << IOSQE_FIXED_FILE_BIT)
+/* issue after inflight IO */
+#define IOSQE_IO_DRAIN		(1U << IOSQE_IO_DRAIN_BIT)
+/* links next sqe */
+#define IOSQE_IO_LINK		(1U << IOSQE_IO_LINK_BIT)
+/* like LINK, but stronger */
+#define IOSQE_IO_HARDLINK	(1U << IOSQE_IO_HARDLINK_BIT)
+/* always go async */
+#define IOSQE_ASYNC		(1U << IOSQE_ASYNC_BIT)
+/* select buffer from sqe->buf_group */
+#define IOSQE_BUFFER_SELECT	(1U << IOSQE_BUFFER_SELECT_BIT)
+
+/*
+ * io_uring_setup() flags
+ */
+#define IORING_SETUP_IOPOLL	(1U << 0)	/* io_context is polled */
+#define IORING_SETUP_SQPOLL	(1U << 1)	/* SQ poll thread */
+#define IORING_SETUP_SQ_AFF	(1U << 2)	/* sq_thread_cpu is valid */
+#define IORING_SETUP_CQSIZE	(1U << 3)	/* app defines CQ size */
+#define IORING_SETUP_CLAMP	(1U << 4)	/* clamp SQ/CQ ring sizes */
+#define IORING_SETUP_ATTACH_WQ	(1U << 5)	/* attach to existing wq */
+
+enum {
+	IORING_OP_NOP,
+	IORING_OP_READV,
+	IORING_OP_WRITEV,
+	IORING_OP_FSYNC,
+	IORING_OP_READ_FIXED,
+	IORING_OP_WRITE_FIXED,
+	IORING_OP_POLL_ADD,
+	IORING_OP_POLL_REMOVE,
+	IORING_OP_SYNC_FILE_RANGE,
+	IORING_OP_SENDMSG,
+	IORING_OP_RECVMSG,
+	IORING_OP_TIMEOUT,
+	IORING_OP_TIMEOUT_REMOVE,
+	IORING_OP_ACCEPT,
+	IORING_OP_ASYNC_CANCEL,
+	IORING_OP_LINK_TIMEOUT,
+	IORING_OP_CONNECT,
+	IORING_OP_FALLOCATE,
+	IORING_OP_OPENAT,
+	IORING_OP_CLOSE,
+	IORING_OP_FILES_UPDATE,
+	IORING_OP_STATX,
+	IORING_OP_READ,
+	IORING_OP_WRITE,
+	IORING_OP_FADVISE,
+	IORING_OP_MADVISE,
+	IORING_OP_SEND,
+	IORING_OP_RECV,
+	IORING_OP_OPENAT2,
+	IORING_OP_EPOLL_CTL,
+	IORING_OP_SPLICE,
+	IORING_OP_PROVIDE_BUFFERS,
+	IORING_OP_REMOVE_BUFFERS,
+	IORING_OP_TEE,
+
+	/* this goes last, obviously */
+	IORING_OP_LAST,
+};
+
+/*
+ * sqe->fsync_flags
+ */
+#define IORING_FSYNC_DATASYNC	(1U << 0)
+
+/*
+ * sqe->timeout_flags
+ */
+#define IORING_TIMEOUT_ABS	(1U << 0)
+
+/*
+ * sqe->splice_flags
+ * extends splice(2) flags
+ */
+#define SPLICE_F_FD_IN_FIXED	(1U << 31) /* the last bit of __u32 */
+
+/*
+ * IO completion data structure (Completion Queue Entry)
+ */
+struct io_uring_cqe {
+	__u64	user_data;	/* sqe->data submission passed back */
+	__s32	res;		/* result code for this event */
+	__u32	flags;
+};
+
+/*
+ * cqe->flags
+ *
+ * IORING_CQE_F_BUFFER	If set, the upper 16 bits are the buffer ID
+ */
+#define IORING_CQE_F_BUFFER		(1U << 0)
+
+enum {
+	IORING_CQE_BUFFER_SHIFT		= 16,
+};
+
+/*
+ * Magic offsets for the application to mmap the data it needs
+ */
+#define IORING_OFF_SQ_RING		0ULL
+#define IORING_OFF_CQ_RING		0x8000000ULL
+#define IORING_OFF_SQES			0x10000000ULL
+
+/*
+ * Filled with the offset for mmap(2)
+ */
+struct io_sqring_offsets {
+	__u32 head;
+	__u32 tail;
+	__u32 ring_mask;
+	__u32 ring_entries;
+	__u32 flags;
+	__u32 dropped;
+	__u32 array;
+	__u32 resv1;
+	__u64 resv2;
+};
+
+/*
+ * sq_ring->flags
+ */
+#define IORING_SQ_NEED_WAKEUP	(1U << 0) /* needs io_uring_enter wakeup */
+#define IORING_SQ_CQ_OVERFLOW	(1U << 1) /* CQ ring is overflown */
+
+struct io_cqring_offsets {
+	__u32 head;
+	__u32 tail;
+	__u32 ring_mask;
+	__u32 ring_entries;
+	__u32 overflow;
+	__u32 cqes;
+	__u32 flags;
+	__u32 resv1;
+	__u64 resv2;
+};
+
+/*
+ * cq_ring->flags
+ */
+
+/* disable eventfd notifications */
+#define IORING_CQ_EVENTFD_DISABLED	(1U << 0)
+
+/*
+ * io_uring_enter(2) flags
+ */
+#define IORING_ENTER_GETEVENTS	(1U << 0)
+#define IORING_ENTER_SQ_WAKEUP	(1U << 1)
+
+/*
+ * Passed in for io_uring_setup(2). Copied back with updated info on success
+ */
+struct io_uring_params {
+	__u32 sq_entries;
+	__u32 cq_entries;
+	__u32 flags;
+	__u32 sq_thread_cpu;
+	__u32 sq_thread_idle;
+	__u32 features;
+	__u32 wq_fd;
+	__u32 resv[3];
+	struct io_sqring_offsets sq_off;
+	struct io_cqring_offsets cq_off;
+};
+
+/*
+ * io_uring_params->features flags
+ */
+#define IORING_FEAT_SINGLE_MMAP		(1U << 0)
+#define IORING_FEAT_NODROP		(1U << 1)
+#define IORING_FEAT_SUBMIT_STABLE	(1U << 2)
+#define IORING_FEAT_RW_CUR_POS		(1U << 3)
+#define IORING_FEAT_CUR_PERSONALITY	(1U << 4)
+#define IORING_FEAT_FAST_POLL		(1U << 5)
+#define IORING_FEAT_POLL_32BITS 	(1U << 6)
+
+/*
+ * io_uring_register(2) opcodes and arguments
+ */
+#define IORING_REGISTER_BUFFERS		0
+#define IORING_UNREGISTER_BUFFERS	1
+#define IORING_REGISTER_FILES		2
+#define IORING_UNREGISTER_FILES		3
+#define IORING_REGISTER_EVENTFD		4
+#define IORING_UNREGISTER_EVENTFD	5
+#define IORING_REGISTER_FILES_UPDATE	6
+#define IORING_REGISTER_EVENTFD_ASYNC	7
+#define IORING_REGISTER_PROBE		8
+#define IORING_REGISTER_PERSONALITY	9
+#define IORING_UNREGISTER_PERSONALITY	10
+
+struct io_uring_files_update {
+	__u32 offset;
+	__u32 resv;
+	__aligned_u64 /* __s32 * */ fds;
+};
+
+#define IO_URING_OP_SUPPORTED	(1U << 0)
+
+struct io_uring_probe_op {
+	__u8 op;
+	__u8 resv;
+	__u16 flags;	/* IO_URING_OP_* flags */
+	__u32 resv2;
+};
+
+struct io_uring_probe {
+	__u8 last_op;	/* last opcode supported */
+	__u8 ops_len;	/* length of ops[] array below */
+	__u16 resv;
+	__u32 resv2[3];
+	struct io_uring_probe_op ops[0];
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/src/liburing/src/liburing.map b/src/liburing/src/liburing.map
new file mode 100644
index 000000000..38bd558a5
--- /dev/null
+++ b/src/liburing/src/liburing.map
@@ -0,0 +1,59 @@
+LIBURING_0.1 {
+	global:
+		io_uring_queue_init;
+		io_uring_queue_mmap;
+		io_uring_queue_exit;
+		io_uring_peek_cqe;
+		io_uring_wait_cqe;
+		io_uring_submit;
+		io_uring_submit_and_wait;
+		io_uring_get_sqe;
+		io_uring_register;
+		io_uring_setup;
+		io_uring_enter;
+		io_uring_mmap;
+		io_uring_register_buffers;
+		io_uring_unregister_buffers;
+		io_uring_register_files;
+		io_uring_unregister_files;
+		io_uring_register_eventfd;
+		io_uring_unregister_eventfd;
+	local:
+		*;
+};
+
+LIBURING_0.2 {
+	global:
+		io_uring_peek_batch_cqe;
+		io_uring_wait_cqe_timeout;
+		io_uring_wait_cqes;
+
+		__io_uring_get_cqe;
+
+		io_uring_queue_init_params;
+		io_uring_register_files_update;
+} LIBURING_0.1;
+
+LIBURING_0.3 {
+} LIBURING_0.2;
+
+LIBURING_0.4 {
+	global:
+		io_uring_ring_dontfork;
+		io_uring_register_probe;
+		io_uring_register_personality;
+		io_uring_unregister_personality;
+		io_uring_get_probe;
+		io_uring_get_probe_ring;
+} LIBURING_0.3;
+
+LIBURING_0.5 {
+} LIBURING_0.4;
+
+LIBURING_0.6 {
+	global:
+		io_uring_register_eventfd_async;
+} LIBURING_0.5;
+
+LIBURING_0.7 {
+} LIBURING_0.6;
diff --git a/src/liburing/src/queue.c b/src/liburing/src/queue.c
new file mode 100644
index 000000000..be80d7a2c
--- /dev/null
+++ b/src/liburing/src/queue.c
@@ -0,0 +1,323 @@
+/* SPDX-License-Identifier: MIT */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <stdbool.h>
+
+#include "liburing/compat.h"
+#include "liburing/io_uring.h"
+#include "liburing.h"
+#include "liburing/barrier.h"
+
+#include "syscall.h"
+
+/*
+ * Returns true if we're not using SQ thread (thus nobody submits but us)
+ * or if IORING_SQ_NEED_WAKEUP is set, so submit thread must be explicitly
+ * awakened. For the latter case, we set the thread wakeup flag.
+ */
+static inline bool sq_ring_needs_enter(struct io_uring *ring,
+				unsigned submitted, unsigned *flags)
+{
+	if (!(ring->flags & IORING_SETUP_SQPOLL) && submitted)
+		return true;
+	if (IO_URING_READ_ONCE(*ring->sq.kflags) & IORING_SQ_NEED_WAKEUP) {
+		*flags |= IORING_ENTER_SQ_WAKEUP;
+		return true;
+	}
+
+	return false;
+}
+
+static inline bool cq_ring_needs_flush(struct io_uring *ring)
+{
+	return IO_URING_READ_ONCE(*ring->sq.kflags) & IORING_SQ_CQ_OVERFLOW;
+}
+
+static int __io_uring_peek_cqe(struct io_uring *ring,
+			       struct io_uring_cqe **cqe_ptr)
+{
+	struct io_uring_cqe *cqe;
+	unsigned head;
+	int err = 0;
+
+	do {
+		io_uring_for_each_cqe(ring, head, cqe)
+			break;
+		if (cqe) {
+			if (cqe->user_data == LIBURING_UDATA_TIMEOUT) {
+				if (cqe->res < 0)
+					err = cqe->res;
+				io_uring_cq_advance(ring, 1);
+				if (!err)
+					continue;
+				cqe = NULL;
+			}
+		}
+		break;
+	} while (1);
+
+	*cqe_ptr = cqe;
+	return err;
+}
+
+int __io_uring_get_cqe(struct io_uring *ring, struct io_uring_cqe **cqe_ptr,
+		       unsigned submit, unsigned wait_nr, sigset_t *sigmask)
+{
+	struct io_uring_cqe *cqe = NULL;
+	const int to_wait = wait_nr;
+	int ret = 0, err;
+
+	do {
+		bool cq_overflow_flush = false;
+		unsigned flags = 0;
+
+		err = __io_uring_peek_cqe(ring, &cqe);
+		if (err)
+			break;
+		if (!cqe && !to_wait && !submit) {
+			if (!cq_ring_needs_flush(ring)) {
+				err = -EAGAIN;
+				break;
+			}
+			cq_overflow_flush = true;
+		}
+		if (wait_nr && cqe)
+			wait_nr--;
+		if (wait_nr || cq_overflow_flush)
+			flags = IORING_ENTER_GETEVENTS;
+		if (submit)
+			sq_ring_needs_enter(ring, submit, &flags);
+		if (wait_nr || submit || cq_overflow_flush)
+			ret = __sys_io_uring_enter(ring->ring_fd, submit,
+						   wait_nr, flags, sigmask);
+		if (ret < 0) {
+			err = -errno;
+		} else if (ret == (int)submit) {
+			submit = 0;
+			/*
+			 * When SETUP_IOPOLL is set, __sys_io_uring enter()
+			 * must be called to reap new completions but the call
+			 * won't be made if both wait_nr and submit are zero
+			 * so preserve wait_nr.
+			 */
+			if (!(ring->flags & IORING_SETUP_IOPOLL))
+				wait_nr = 0;
+		} else {
+			submit -= ret;
+		}
+		if (cqe)
+			break;
+	} while (!err);
+
+	*cqe_ptr = cqe;
+	return err;
+}
+
+/*
+ * Fill in an array of IO completions up to count, if any are available.
+ * Returns the amount of IO completions filled.
+ */
+unsigned io_uring_peek_batch_cqe(struct io_uring *ring,
+				 struct io_uring_cqe **cqes, unsigned count)
+{
+	unsigned ready;
+	bool overflow_checked = false;
+
+again:
+	ready = io_uring_cq_ready(ring);
+	if (ready) {
+		unsigned head = *ring->cq.khead;
+		unsigned mask = *ring->cq.kring_mask;
+		unsigned last;
+		int i = 0;
+
+		count = count > ready ? ready : count;
+		last = head + count;
+		for (;head != last; head++, i++)
+			cqes[i] = &ring->cq.cqes[head & mask];
+
+		return count;
+	}
+
+	if (overflow_checked)
+		goto done;
+
+	if (cq_ring_needs_flush(ring)) {
+		__sys_io_uring_enter(ring->ring_fd, 0, 0,
+				     IORING_ENTER_GETEVENTS, NULL);
+		overflow_checked = true;
+		goto again;
+	}
+
+done:
+	return 0;
+}
+
+/*
+ * Sync internal state with kernel ring state on the SQ side. Returns the
+ * number of pending items in the SQ ring, for the shared ring.
+ */
+static int __io_uring_flush_sq(struct io_uring *ring)
+{
+	struct io_uring_sq *sq = &ring->sq;
+	const unsigned mask = *sq->kring_mask;
+	unsigned ktail, to_submit;
+
+	if (sq->sqe_head == sq->sqe_tail) {
+		ktail = *sq->ktail;
+		goto out;
+	}
+
+	/*
+	 * Fill in sqes that we have queued up, adding them to the kernel ring
+	 */
+	ktail = *sq->ktail;
+	to_submit = sq->sqe_tail - sq->sqe_head;
+	while (to_submit--) {
+		sq->array[ktail & mask] = sq->sqe_head & mask;
+		ktail++;
+		sq->sqe_head++;
+	}
+
+	/*
+	 * Ensure that the kernel sees the SQE updates before it sees the tail
+	 * update.
+	 */
+	io_uring_smp_store_release(sq->ktail, ktail);
+out:
+	return ktail - *sq->khead;
+}
+
+/*
+ * Like io_uring_wait_cqe(), except it accepts a timeout value as well. Note
+ * that an sqe is used internally to handle the timeout. Applications using
+ * this function must never set sqe->user_data to LIBURING_UDATA_TIMEOUT!
+ *
+ * If 'ts' is specified, the application need not call io_uring_submit() before
+ * calling this function, as we will do that on its behalf. From this it also
+ * follows that this function isn't safe to use for applications that split SQ
+ * and CQ handling between two threads and expect that to work without
+ * synchronization, as this function manipulates both the SQ and CQ side.
+ */
+int io_uring_wait_cqes(struct io_uring *ring, struct io_uring_cqe **cqe_ptr,
+		       unsigned wait_nr, struct __kernel_timespec *ts,
+		       sigset_t *sigmask)
+{
+	unsigned to_submit = 0;
+
+	if (ts) {
+		struct io_uring_sqe *sqe;
+		int ret;
+
+		/*
+		 * If the SQ ring is full, we may need to submit IO first
+		 */
+		sqe = io_uring_get_sqe(ring);
+		if (!sqe) {
+			ret = io_uring_submit(ring);
+			if (ret < 0)
+				return ret;
+			sqe = io_uring_get_sqe(ring);
+			if (!sqe)
+				return -EAGAIN;
+		}
+		io_uring_prep_timeout(sqe, ts, wait_nr, 0);
+		sqe->user_data = LIBURING_UDATA_TIMEOUT;
+		to_submit = __io_uring_flush_sq(ring);
+	}
+
+	return __io_uring_get_cqe(ring, cqe_ptr, to_submit, wait_nr, sigmask);
+}
+
+/*
+ * See io_uring_wait_cqes() - this function is the same, it just always uses
+ * '1' as the wait_nr.
+ */
+int io_uring_wait_cqe_timeout(struct io_uring *ring,
+			      struct io_uring_cqe **cqe_ptr,
+			      struct __kernel_timespec *ts)
+{
+	return io_uring_wait_cqes(ring, cqe_ptr, 1, ts, NULL);
+}
+
+/*
+ * Submit sqes acquired from io_uring_get_sqe() to the kernel.
+ *
+ * Returns number of sqes submitted
+ */
+static int __io_uring_submit(struct io_uring *ring, unsigned submitted,
+			     unsigned wait_nr)
+{
+	unsigned flags;
+	int ret;
+
+	flags = 0;
+	if (sq_ring_needs_enter(ring, submitted, &flags) || wait_nr) {
+		if (wait_nr || (ring->flags & IORING_SETUP_IOPOLL))
+			flags |= IORING_ENTER_GETEVENTS;
+
+		ret = __sys_io_uring_enter(ring->ring_fd, submitted, wait_nr,
+						flags, NULL);
+		if (ret < 0)
+			return -errno;
+	} else
+		ret = submitted;
+
+	return ret;
+}
+
+static int __io_uring_submit_and_wait(struct io_uring *ring, unsigned wait_nr)
+{
+	return __io_uring_submit(ring, __io_uring_flush_sq(ring), wait_nr);
+}
+
+/*
+ * Submit sqes acquired from io_uring_get_sqe() to the kernel.
+ *
+ * Returns number of sqes submitted
+ */
+int io_uring_submit(struct io_uring *ring)
+{
+	return __io_uring_submit_and_wait(ring, 0);
+}
+
+/*
+ * Like io_uring_submit(), but allows waiting for events as well.
+ *
+ * Returns number of sqes submitted
+ */
+int io_uring_submit_and_wait(struct io_uring *ring, unsigned wait_nr)
+{
+	return __io_uring_submit_and_wait(ring, wait_nr);
+}
+
+static inline struct io_uring_sqe *
+__io_uring_get_sqe(struct io_uring_sq *sq, unsigned int __head)
+{
+	unsigned int __next = (sq)->sqe_tail + 1;
+	struct io_uring_sqe *__sqe = NULL;
+
+	if (__next - __head <= *(sq)->kring_entries) {
+		__sqe = &(sq)->sqes[(sq)->sqe_tail & *(sq)->kring_mask];
+		(sq)->sqe_tail = __next;
+	}
+	return __sqe;
+}
+
+/*
+ * Return an sqe to fill. Application must later call io_uring_submit()
+ * when it's ready to tell the kernel about it. The caller may call this
+ * function multiple times before calling io_uring_submit().
+ *
+ * Returns a vacant sqe, or NULL if we're full.
+ */
+struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring)
+{
+	struct io_uring_sq *sq = &ring->sq;
+
+	return __io_uring_get_sqe(sq, io_uring_smp_load_acquire(sq->khead));
+}
diff --git a/src/liburing/src/register.c b/src/liburing/src/register.c
new file mode 100644
index 000000000..327a8ce97
--- /dev/null
+++ b/src/liburing/src/register.c
@@ -0,0 +1,161 @@
+/* SPDX-License-Identifier: MIT */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+
+#include "liburing/compat.h"
+#include "liburing/io_uring.h"
+#include "liburing.h"
+
+#include "syscall.h"
+
+int io_uring_register_buffers(struct io_uring *ring, const struct iovec *iovecs,
+			      unsigned nr_iovecs)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_REGISTER_BUFFERS,
+					iovecs, nr_iovecs);
+	if (ret < 0)
+		return -errno;
+
+	return 0;
+}
+
+int io_uring_unregister_buffers(struct io_uring *ring)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_UNREGISTER_BUFFERS,
+					NULL, 0);
+	if (ret < 0)
+		return -errno;
+
+	return 0;
+}
+
+/*
+ * Register an update for an existing file set. The updates will start at
+ * 'off' in the original array, and 'nr_files' is the number of files we'll
+ * update.
+ *
+ * Returns number of files updated on success, -ERROR on failure.
+ */
+int io_uring_register_files_update(struct io_uring *ring, unsigned off,
+				   int *files, unsigned nr_files)
+{
+	struct io_uring_files_update up = {
+		.offset	= off,
+		.fds	= (unsigned long) files,
+	};
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd,
+					IORING_REGISTER_FILES_UPDATE, &up,
+					nr_files);
+	if (ret < 0)
+		return -errno;
+
+	return ret;
+}
+
+int io_uring_register_files(struct io_uring *ring, const int *files,
+			      unsigned nr_files)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_REGISTER_FILES,
+					files, nr_files);
+	if (ret < 0)
+		return -errno;
+
+	return 0;
+}
+
+int io_uring_unregister_files(struct io_uring *ring)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_UNREGISTER_FILES,
+					NULL, 0);
+	if (ret < 0)
+		return -errno;
+
+	return 0;
+}
+
+int io_uring_register_eventfd(struct io_uring *ring, int event_fd)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_REGISTER_EVENTFD,
+					&event_fd, 1);
+	if (ret < 0)
+		return -errno;
+
+	return 0;
+}
+
+int io_uring_unregister_eventfd(struct io_uring *ring)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_UNREGISTER_EVENTFD,
+					NULL, 0);
+	if (ret < 0)
+		return -errno;
+
+	return 0;
+}
+
+int io_uring_register_eventfd_async(struct io_uring *ring, int event_fd)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_REGISTER_EVENTFD_ASYNC,
+			&event_fd, 1);
+	if (ret < 0)
+		return -errno;
+
+	return 0;
+}
+
+int io_uring_register_probe(struct io_uring *ring, struct io_uring_probe *p,
+			    unsigned int nr_ops)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_REGISTER_PROBE,
+					p, nr_ops);
+	if (ret < 0)
+		return -errno;
+
+	return 0;
+}
+
+int io_uring_register_personality(struct io_uring *ring)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_REGISTER_PERSONALITY,
+					NULL, 0);
+	if (ret < 0)
+		return -errno;
+
+	return ret;
+}
+
+int io_uring_unregister_personality(struct io_uring *ring, int id)
+{
+	int ret;
+
+	ret = __sys_io_uring_register(ring->ring_fd, IORING_UNREGISTER_PERSONALITY,
+					NULL, id);
+	if (ret < 0)
+		return -errno;
+
+	return ret;
+}
diff --git a/src/liburing/src/setup.c b/src/liburing/src/setup.c
new file mode 100644
index 000000000..2b17b949c
--- /dev/null
+++ b/src/liburing/src/setup.c
@@ -0,0 +1,205 @@
+/* SPDX-License-Identifier: MIT */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "liburing/compat.h"
+#include "liburing/io_uring.h"
+#include "liburing.h"
+
+#include "syscall.h"
+
+static void io_uring_unmap_rings(struct io_uring_sq *sq, struct io_uring_cq *cq)
+{
+	munmap(sq->ring_ptr, sq->ring_sz);
+	if (cq->ring_ptr && cq->ring_ptr != sq->ring_ptr)
+		munmap(cq->ring_ptr, cq->ring_sz);
+}
+
+static int io_uring_mmap(int fd, struct io_uring_params *p,
+			 struct io_uring_sq *sq, struct io_uring_cq *cq)
+{
+	size_t size;
+	int ret;
+
+	sq->ring_sz = p->sq_off.array + p->sq_entries * sizeof(unsigned);
+	cq->ring_sz = p->cq_off.cqes + p->cq_entries * sizeof(struct io_uring_cqe);
+
+	if (p->features & IORING_FEAT_SINGLE_MMAP) {
+		if (cq->ring_sz > sq->ring_sz)
+			sq->ring_sz = cq->ring_sz;
+		cq->ring_sz = sq->ring_sz;
+	}
+	sq->ring_ptr = mmap(0, sq->ring_sz, PROT_READ | PROT_WRITE,
+			MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_SQ_RING);
+	if (sq->ring_ptr == MAP_FAILED)
+		return -errno;
+
+	if (p->features & IORING_FEAT_SINGLE_MMAP) {
+		cq->ring_ptr = sq->ring_ptr;
+	} else {
+		cq->ring_ptr = mmap(0, cq->ring_sz, PROT_READ | PROT_WRITE,
+				MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_CQ_RING);
+		if (cq->ring_ptr == MAP_FAILED) {
+			cq->ring_ptr = NULL;
+			ret = -errno;
+			goto err;
+		}
+	}
+
+	sq->khead = sq->ring_ptr + p->sq_off.head;
+	sq->ktail = sq->ring_ptr + p->sq_off.tail;
+	sq->kring_mask = sq->ring_ptr + p->sq_off.ring_mask;
+	sq->kring_entries = sq->ring_ptr + p->sq_off.ring_entries;
+	sq->kflags = sq->ring_ptr + p->sq_off.flags;
+	sq->kdropped = sq->ring_ptr + p->sq_off.dropped;
+	sq->array = sq->ring_ptr + p->sq_off.array;
+
+	size = p->sq_entries * sizeof(struct io_uring_sqe);
+	sq->sqes = mmap(0, size, PROT_READ | PROT_WRITE,
+				MAP_SHARED | MAP_POPULATE, fd,
+				IORING_OFF_SQES);
+	if (sq->sqes == MAP_FAILED) {
+		ret = -errno;
+err:
+		io_uring_unmap_rings(sq, cq);
+		return ret;
+	}
+
+	cq->khead = cq->ring_ptr + p->cq_off.head;
+	cq->ktail = cq->ring_ptr + p->cq_off.tail;
+	cq->kring_mask = cq->ring_ptr + p->cq_off.ring_mask;
+	cq->kring_entries = cq->ring_ptr + p->cq_off.ring_entries;
+	cq->koverflow = cq->ring_ptr + p->cq_off.overflow;
+	cq->cqes = cq->ring_ptr + p->cq_off.cqes;
+	if (p->cq_off.flags)
+		cq->kflags = cq->ring_ptr + p->cq_off.flags;
+	return 0;
+}
+
+/*
+ * For users that want to specify sq_thread_cpu or sq_thread_idle, this
+ * interface is a convenient helper for mmap()ing the rings.
+ * Returns -errno on error, or zero on success.  On success, 'ring'
+ * contains the necessary information to read/write to the rings.
+ */
+int io_uring_queue_mmap(int fd, struct io_uring_params *p, struct io_uring *ring)
+{
+	int ret;
+
+	memset(ring, 0, sizeof(*ring));
+	ret = io_uring_mmap(fd, p, &ring->sq, &ring->cq);
+	if (!ret) {
+		ring->flags = p->flags;
+		ring->ring_fd = fd;
+	}
+	return ret;
+}
+
+/*
+ * Ensure that the mmap'ed rings aren't available to a child after a fork(2).
+ * This uses madvise(..., MADV_DONTFORK) on the mmap'ed ranges.
+ */
+int io_uring_ring_dontfork(struct io_uring *ring)
+{
+	size_t len;
+	int ret;
+
+	if (!ring->sq.ring_ptr || !ring->sq.sqes || !ring->cq.ring_ptr)
+		return -EINVAL;
+
+	len = *ring->sq.kring_entries * sizeof(struct io_uring_sqe);
+	ret = madvise(ring->sq.sqes, len, MADV_DONTFORK);
+	if (ret == -1)
+		return -errno;
+
+	len = ring->sq.ring_sz;
+	ret = madvise(ring->sq.ring_ptr, len, MADV_DONTFORK);
+	if (ret == -1)
+		return -errno;
+
+	if (ring->cq.ring_ptr != ring->sq.ring_ptr) {
+		len = ring->cq.ring_sz;
+		ret = madvise(ring->cq.ring_ptr, len, MADV_DONTFORK);
+		if (ret == -1)
+			return -errno;
+	}
+
+	return 0;
+}
+
+int io_uring_queue_init_params(unsigned entries, struct io_uring *ring,
+			       struct io_uring_params *p)
+{
+	int fd, ret;
+
+	fd = __sys_io_uring_setup(entries, p);
+	if (fd < 0)
+		return -errno;
+
+	ret = io_uring_queue_mmap(fd, p, ring);
+	if (ret)
+		close(fd);
+
+	return ret;
+}
+
+/*
+ * Returns -errno on error, or zero on success. On success, 'ring'
+ * contains the necessary information to read/write to the rings.
+ */
+int io_uring_queue_init(unsigned entries, struct io_uring *ring, unsigned flags)
+{
+	struct io_uring_params p;
+
+	memset(&p, 0, sizeof(p));
+	p.flags = flags;
+
+	return io_uring_queue_init_params(entries, ring, &p);
+}
+
+void io_uring_queue_exit(struct io_uring *ring)
+{
+	struct io_uring_sq *sq = &ring->sq;
+	struct io_uring_cq *cq = &ring->cq;
+
+	munmap(sq->sqes, *sq->kring_entries * sizeof(struct io_uring_sqe));
+	io_uring_unmap_rings(sq, cq);
+	close(ring->ring_fd);
+}
+
+struct io_uring_probe *io_uring_get_probe_ring(struct io_uring *ring)
+{
+	struct io_uring_probe *probe;
+	int r;
+
+	size_t len = sizeof(*probe) + 256 * sizeof(struct io_uring_probe_op);
+	probe = malloc(len);
+	memset(probe, 0, len);
+	r = io_uring_register_probe(ring, probe, 256);
+	if (r < 0)
+		goto fail;
+
+	return probe;
+fail:
+	free(probe);
+	return NULL;
+}
+
+struct io_uring_probe *io_uring_get_probe(void)
+{
+	struct io_uring ring;
+	struct io_uring_probe* probe = NULL;
+
+	int r = io_uring_queue_init(2, &ring, 0);
+	if (r < 0)
+		return NULL;
+
+	probe = io_uring_get_probe_ring(&ring);
+	io_uring_queue_exit(&ring);
+	return probe;
+}
diff --git a/src/liburing/src/syscall.c b/src/liburing/src/syscall.c
new file mode 100644
index 000000000..c41e0998d
--- /dev/null
+++ b/src/liburing/src/syscall.c
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Will go away once libc support is there
+ */
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <sys/uio.h>
+#include <signal.h>
+#include "liburing/compat.h"
+#include "liburing/io_uring.h"
+#include "syscall.h"
+
+#ifdef __alpha__
+/*
+ * alpha is the only exception, all other architectures
+ * have common numbers for new system calls.
+ */
+# ifndef __NR_io_uring_setup
+#  define __NR_io_uring_setup		535
+# endif
+# ifndef __NR_io_uring_enter
+#  define __NR_io_uring_enter		536
+# endif
+# ifndef __NR_io_uring_register
+#  define __NR_io_uring_register	537
+# endif
+#else /* !__alpha__ */
+# ifndef __NR_io_uring_setup
+#  define __NR_io_uring_setup		425
+# endif
+# ifndef __NR_io_uring_enter
+#  define __NR_io_uring_enter		426
+# endif
+# ifndef __NR_io_uring_register
+#  define __NR_io_uring_register	427
+# endif
+#endif
+
+int __sys_io_uring_register(int fd, unsigned opcode, const void *arg,
+			    unsigned nr_args)
+{
+	return syscall(__NR_io_uring_register, fd, opcode, arg, nr_args);
+}
+
+int __sys_io_uring_setup(unsigned entries, struct io_uring_params *p)
+{
+	return syscall(__NR_io_uring_setup, entries, p);
+}
+
+int __sys_io_uring_enter(int fd, unsigned to_submit, unsigned min_complete,
+			 unsigned flags, sigset_t *sig)
+{
+	return syscall(__NR_io_uring_enter, fd, to_submit, min_complete,
+			flags, sig, _NSIG / 8);
+}
diff --git a/src/liburing/src/syscall.h b/src/liburing/src/syscall.h
new file mode 100644
index 000000000..7e299d419
--- /dev/null
+++ b/src/liburing/src/syscall.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: MIT */
+#ifndef LIBURING_SYSCALL_H
+#define LIBURING_SYSCALL_H
+
+/*
+ * System calls
+ */
+extern int __sys_io_uring_setup(unsigned entries, struct io_uring_params *p);
+extern int __sys_io_uring_enter(int fd, unsigned to_submit,
+	unsigned min_complete, unsigned flags, sigset_t *sig);
+extern int __sys_io_uring_register(int fd, unsigned int opcode, const void *arg,
+	unsigned int nr_args);
+
+#endif