diff options
| -rw-r--r-- | .gitignore | 10 | ||||
| -rw-r--r-- | COPYING | 515 | ||||
| -rw-r--r-- | Makefile | 32 | ||||
| -rw-r--r-- | liburing.spec | 55 | ||||
| -rw-r--r-- | src/Makefile | 61 | ||||
| -rw-r--r-- | src/barrier.h | 16 | ||||
| -rw-r--r-- | src/io_uring.c | 193 | ||||
| -rw-r--r-- | src/io_uring.h | 115 | ||||
| -rw-r--r-- | src/liburing.h | 57 | ||||
| -rw-r--r-- | src/liburing.map | 11 | ||||
| -rw-r--r-- | src/syscall.c | 31 | ||||
| -rw-r--r-- | test/io_uring-test.c | 90 |
12 files changed, 1186 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..ec8f90b --- /dev/null +++ b/.gitignore @@ -0,0 +1,10 @@ +*.rej +*.orig +*~ +/*.patch + +*.o +*.o[ls] + +/src/liburing.a +/src/liburing.so* @@ -0,0 +1,515 @@ + + GNU LESSER GENERAL PUBLIC LICENSE + Version 2.1, February 1999 + + Copyright (C) 1991, 1999 Free Software Foundation, Inc. + 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + +[This is the first released version of the Lesser GPL. It also counts + as the successor of the GNU Library Public License, version 2, hence + the version number 2.1.] + + Preamble + + The licenses for most software are designed to take away your +freedom to share and change it. By contrast, the GNU General Public +Licenses are intended to guarantee your freedom to share and change +free software--to make sure the software is free for all its users. + + This license, the Lesser General Public License, applies to some +specially designated software packages--typically libraries--of the +Free Software Foundation and other authors who decide to use it. You +can use it too, but we suggest you first think carefully about whether +this license or the ordinary General Public License is the better +strategy to use in any particular case, based on the explanations +below. + + When we speak of free software, we are referring to freedom of use, +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 and use pieces of +it in new free programs; and that you are informed that you can do +these things. + + To protect your rights, we need to make restrictions that forbid +distributors to deny you these rights or to ask you to surrender these +rights. These restrictions translate to certain responsibilities for +you if you distribute copies of the library or if you modify it. + + For example, if you distribute copies of the library, whether gratis +or for a fee, you must give the recipients all the rights that we gave +you. You must make sure that they, too, receive or can get the source +code. If you link other code with the library, you must provide +complete object files to the recipients, so that they can relink them +with the library after making changes to the library and recompiling +it. And you must show them these terms so they know their rights. + + We protect your rights with a two-step method: (1) we copyright the +library, and (2) we offer you this license, which gives you legal +permission to copy, distribute and/or modify the library. + + To protect each distributor, we want to make it very clear that +there is no warranty for the free library. Also, if the library is +modified by someone else and passed on, the recipients should know +that what they have is not the original version, so that the original +author's reputation will not be affected by problems that might be +introduced by others. +^L + Finally, software patents pose a constant threat to the existence of +any free program. We wish to make sure that a company cannot +effectively restrict the users of a free program by obtaining a +restrictive license from a patent holder. Therefore, we insist that +any patent license obtained for a version of the library must be +consistent with the full freedom of use specified in this license. + + Most GNU software, including some libraries, is covered by the +ordinary GNU General Public License. This license, the GNU Lesser +General Public License, applies to certain designated libraries, and +is quite different from the ordinary General Public License. We use +this license for certain libraries in order to permit linking those +libraries into non-free programs. + + When a program is linked with a library, whether statically or using +a shared library, the combination of the two is legally speaking a +combined work, a derivative of the original library. The ordinary +General Public License therefore permits such linking only if the +entire combination fits its criteria of freedom. The Lesser General +Public License permits more lax criteria for linking other code with +the library. + + We call this license the "Lesser" General Public License because it +does Less to protect the user's freedom than the ordinary General +Public License. It also provides other free software developers Less +of an advantage over competing non-free programs. These disadvantages +are the reason we use the ordinary General Public License for many +libraries. However, the Lesser license provides advantages in certain +special circumstances. + + For example, on rare occasions, there may be a special need to +encourage the widest possible use of a certain library, so that it +becomes +a de-facto standard. To achieve this, non-free programs must be +allowed to use the library. A more frequent case is that a free +library does the same job as widely used non-free libraries. In this +case, there is little to gain by limiting the free library to free +software only, so we use the Lesser General Public License. + + In other cases, permission to use a particular library in non-free +programs enables a greater number of people to use a large body of +free software. For example, permission to use the GNU C Library in +non-free programs enables many more people to use the whole GNU +operating system, as well as its variant, the GNU/Linux operating +system. + + Although the Lesser General Public License is Less protective of the +users' freedom, it does ensure that the user of a program that is +linked with the Library has the freedom and the wherewithal to run +that program using a modified version of the Library. + + The precise terms and conditions for copying, distribution and +modification follow. Pay close attention to the difference between a +"work based on the library" and a "work that uses the library". The +former contains code derived from the library, whereas the latter must +be combined with the library in order to run. +^L + GNU LESSER GENERAL PUBLIC LICENSE + TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION + + 0. This License Agreement applies to any software library or other +program which contains a notice placed by the copyright holder or +other authorized party saying it may be distributed under the terms of +this Lesser General Public License (also called "this License"). +Each licensee is addressed as "you". + + A "library" means a collection of software functions and/or data +prepared so as to be conveniently linked with application programs +(which use some of those functions and data) to form executables. + + The "Library", below, refers to any such software library or work +which has been distributed under these terms. A "work based on the +Library" means either the Library or any derivative work under +copyright law: that is to say, a work containing the Library or a +portion of it, either verbatim or with modifications and/or translated +straightforwardly into another language. (Hereinafter, translation is +included without limitation in the term "modification".) + + "Source code" for a work means the preferred form of the work for +making modifications to it. For a library, complete source code means +all the source code for all modules it contains, plus any associated +interface definition files, plus the scripts used to control +compilation +and installation of the library. + + Activities other than copying, distribution and modification are not +covered by this License; they are outside its scope. The act of +running a program using the Library is not restricted, and output from +such a program is covered only if its contents constitute a work based +on the Library (independent of the use of the Library in a tool for +writing it). Whether that is true depends on what the Library does +and what the program that uses the Library does. + + 1. You may copy and distribute verbatim copies of the Library's +complete 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 distribute a copy of this License along with the +Library. + + 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 Library or any portion +of it, thus forming a work based on the Library, 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) The modified work must itself be a software library. + + b) You must cause the files modified to carry prominent notices + stating that you changed the files and the date of any change. + + c) You must cause the whole of the work to be licensed at no + charge to all third parties under the terms of this License. + + d) If a facility in the modified Library refers to a function or a + table of data to be supplied by an application program that uses + the facility, other than as an argument passed when the facility + is invoked, then you must make a good faith effort to ensure that, + in the event an application does not supply such function or + table, the facility still operates, and performs whatever part of + its purpose remains meaningful. + + (For example, a function in a library to compute square roots has + a purpose that is entirely well-defined independent of the + application. Therefore, Subsection 2d requires that any + application-supplied function or table used by this function must + be optional: if the application does not supply it, the square + root function must still compute square roots.) + +These requirements apply to the modified work as a whole. If +identifiable sections of that work are not derived from the Library, +and can be reasonably considered independent and separate works in +themselves, then this License, and its terms, do not apply to those +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 Library, 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 Library. + +In addition, mere aggregation of another work not based on the Library +with the Library (or with a work based on the Library) on a volume of +a storage or distribution medium does not bring the other work under +the scope of this License. + + 3. You may opt to apply the terms of the ordinary GNU General Public +License instead of this License to a given copy of the Library. To do +this, you must alter all the notices that refer to this License, so +that they refer to the ordinary GNU General Public License, version 2, +instead of to this License. (If a newer version than version 2 of the +ordinary GNU General Public License has appeared, then you can specify +that version instead if you wish.) Do not make any other change in +these notices. +^L + Once this change is made in a given copy, it is irreversible for +that copy, so the ordinary GNU General Public License applies to all +subsequent copies and derivative works made from that copy. + + This option is useful when you wish to copy part of the code of +the Library into a program that is not a library. + + 4. You may copy and distribute the Library (or a portion or +derivative of it, under Section 2) in object code or executable form +under the terms of Sections 1 and 2 above provided that you 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. + + If distribution of object code is made by offering access to copy +from a designated place, then offering equivalent access to copy the +source code from the same place satisfies the requirement to +distribute the source code, even though third parties are not +compelled to copy the source along with the object code. + + 5. A program that contains no derivative of any portion of the +Library, but is designed to work with the Library by being compiled or +linked with it, is called a "work that uses the Library". Such a +work, in isolation, is not a derivative work of the Library, and +therefore falls outside the scope of this License. + + However, linking a "work that uses the Library" with the Library +creates an executable that is a derivative of the Library (because it +contains portions of the Library), rather than a "work that uses the +library". The executable is therefore covered by this License. +Section 6 states terms for distribution of such executables. + + When a "work that uses the Library" uses material from a header file +that is part of the Library, the object code for the work may be a +derivative work of the Library even though the source code is not. +Whether this is true is especially significant if the work can be +linked without the Library, or if the work is itself a library. The +threshold for this to be true is not precisely defined by law. + + If such an object file uses only numerical parameters, data +structure layouts and accessors, and small macros and small inline +functions (ten lines or less in length), then the use of the object +file is unrestricted, regardless of whether it is legally a derivative +work. (Executables containing this object code plus portions of the +Library will still fall under Section 6.) + + Otherwise, if the work is a derivative of the Library, you may +distribute the object code for the work under the terms of Section 6. +Any executables containing that work also fall under Section 6, +whether or not they are linked directly with the Library itself. +^L + 6. As an exception to the Sections above, you may also combine or +link a "work that uses the Library" with the Library to produce a +work containing portions of the Library, and distribute that work +under terms of your choice, provided that the terms permit +modification of the work for the customer's own use and reverse +engineering for debugging such modifications. + + You must give prominent notice with each copy of the work that the +Library is used in it and that the Library and its use are covered by +this License. You must supply a copy of this License. If the work +during execution displays copyright notices, you must include the +copyright notice for the Library among them, as well as a reference +directing the user to the copy of this License. Also, you must do one +of these things: + + a) Accompany the work with the complete corresponding + machine-readable source code for the Library including whatever + changes were used in the work (which must be distributed under + Sections 1 and 2 above); and, if the work is an executable linked + with the Library, with the complete machine-readable "work that + uses the Library", as object code and/or source code, so that the + user can modify the Library and then relink to produce a modified + executable containing the modified Library. (It is understood + that the user who changes the contents of definitions files in the + Library will not necessarily be able to recompile the application + to use the modified definitions.) + + b) Use a suitable shared library mechanism for linking with the + Library. A suitable mechanism is one that (1) uses at run time a + copy of the library already present on the user's computer system, + rather than copying library functions into the executable, and (2) + will operate properly with a modified version of the library, if + the user installs one, as long as the modified version is + interface-compatible with the version that the work was made with. + + c) Accompany the work with a written offer, valid for at + least three years, to give the same user the materials + specified in Subsection 6a, above, for a charge no more + than the cost of performing this distribution. + + d) If distribution of the work is made by offering access to copy + from a designated place, offer equivalent access to copy the above + specified materials from the same place. + + e) Verify that the user has already received a copy of these + materials or that you have already sent this user a copy. + + For an executable, the required form of the "work that uses the +Library" must include any data and utility programs needed for +reproducing the executable from it. However, as a special exception, +the materials to be distributed need not include anything that is +normally distributed (in either source or binary form) with the major +components (compiler, kernel, and so on) of the operating system on +which the executable runs, unless that component itself accompanies +the executable. + + It may happen that this requirement contradicts the license +restrictions of other proprietary libraries that do not normally +accompany the operating system. Such a contradiction means you cannot +use both them and the Library together in an executable that you +distribute. +^L + 7. You may place library facilities that are a work based on the +Library side-by-side in a single library together with other library +facilities not covered by this License, and distribute such a combined +library, provided that the separate distribution of the work based on +the Library and of the other library facilities is otherwise +permitted, and provided that you do these two things: + + a) Accompany the combined library with a copy of the same work + based on the Library, uncombined with any other library + facilities. This must be distributed under the terms of the + Sections above. + + b) Give prominent notice with the combined library of the fact + that part of it is a work based on the Library, and explaining + where to find the accompanying uncombined form of the same work. + + 8. You may not copy, modify, sublicense, link with, or distribute +the Library except as expressly provided under this License. Any +attempt otherwise to copy, modify, sublicense, link with, or +distribute the Library 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. + + 9. 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 Library or its derivative works. These actions are +prohibited by law if you do not accept this License. Therefore, by +modifying or distributing the Library (or any work based on the +Library), you indicate your acceptance of this License to do so, and +all its terms and conditions for copying, distributing or modifying +the Library or works based on it. + + 10. Each time you redistribute the Library (or any work based on the +Library), the recipient automatically receives a license from the +original licensor to copy, distribute, link with or modify the Library +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 with +this License. +^L + 11. 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 Library at all. For example, if a patent +license would not permit royalty-free redistribution of the Library 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 Library. + +If any portion of this section is held invalid or unenforceable under +any particular circumstance, the balance of the section is intended to +apply, and the section as a whole is intended to apply in other +circumstances. + +It is not the purpose of this section to induce you to infringe any +patents or other property right claims or to contest validity of any +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 +generous contributions to the wide range of software distributed +through that system in reliance on consistent application of that +system; it is up to the author/donor to decide if he or she is willing +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. + + 12. If the distribution and/or use of the Library is restricted in +certain countries either by patents or by copyrighted interfaces, the +original copyright holder who places the Library 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. + + 13. The Free Software Foundation may publish revised and/or new +versions of the Lesser 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 Library +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 Library does not specify a +license version number, you may choose any version ever published by +the Free Software Foundation. +^L + 14. If you wish to incorporate parts of the Library into other free +programs whose distribution conditions are incompatible with these, +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 + + 15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO +WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW. +EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR +OTHER PARTIES PROVIDE THE LIBRARY "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 +LIBRARY IS WITH YOU. SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME +THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. + + 16. 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 LIBRARY 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 +LIBRARY (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 LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF +SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH +DAMAGES. + + END OF TERMS AND CONDITIONS +^L + How to Apply These Terms to Your New Libraries + + If you develop a new library, and you want it to be of the greatest +possible use to the public, we recommend making it free software that +everyone can redistribute and change. You can do so by permitting +redistribution under these terms (or, alternatively, under the terms +of the ordinary General Public License). + + To apply these terms, attach the following notices to the library. +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 library's name and a brief idea of what it +does.> + Copyright (C) <year> <name of author> + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + +Also add information on how to contact you by electronic and paper +mail. + +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/Makefile b/Makefile new file mode 100644 index 0000000..88e98c9 --- /dev/null +++ b/Makefile @@ -0,0 +1,32 @@ +NAME=liburing +SPECFILE=$(NAME).spec +VERSION=$(shell awk '/Version:/ { print $$2 }' $(SPECFILE)) +TAG = $(NAME)-$(VERSION) +RPMBUILD=$(shell `which rpmbuild >&/dev/null` && echo "rpmbuild" || echo "rpm") + +prefix=/usr +includedir=$(prefix)/include +libdir=$(prefix)/lib + +default: all + +all: + @$(MAKE) -C src + +install: + @$(MAKE) -C src install prefix=$(DESTDIR)$(prefix) includedir=$(DESTDIR)$(includedir) libdir=$(DESTDIR)$(libdir) + +clean: + @$(MAKE) -C src clean + +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 $(SPECFILE) diff --git a/liburing.spec b/liburing.spec new file mode 100644 index 0000000..35da5cb --- /dev/null +++ b/liburing.spec @@ -0,0 +1,55 @@ +Name: liburing +Version: 0.1 +Release: 1 +Summary: Linux-native io_uring I/O access library +License: LGPL +Group: System Environment/Libraries +Source: %{name}-%{version}.tar.gz +BuildRoot: %{_tmppath}/%{name}-root + +%description +Provides native async IO for the Linux kernel, in a fast and efficient +manner, for both buffered and O_DIRECT. + +%package devel +Summary: Development files for Linux-native io_uring I/O access library +Group: Development/System +Requires: liburing +Provides: liburing.so.1 + +%description devel +This package provides header files to include and libraries to link with +for the Linux-native io_uring. + +%prep +%setup + +%build +make + +%install +[ "$RPM_BUILD_ROOT" != "/" ] && rm -rf $RPM_BUILD_ROOT + +make install DESTDIR=$RPM_BUILD_ROOT prefix=/usr libdir=/%{_libdir} + +%clean +[ "$RPM_BUILD_ROOT" != "/" ] && rm -rf $RPM_BUILD_ROOT + +%post -p /sbin/ldconfig + +%postun -p /sbin/ldconfig + +%files +%defattr(-,root,root) +%attr(0755,root,root) %{_libdir}/liburing.so.* +%doc COPYING TODO + +%files devel +%defattr(-,root,root) +%attr(0644,root,root) %{_includedir}/* +%attr(0755,root,root) %{_libdir}/liburing.so +%attr(0644,root,root) %{_libdir}/liburing.a + +%changelog +* Tue Jan 8 2019 Jens Axboe <axboe@kernel.dk> - 0.1 +- Initial version diff --git a/src/Makefile b/src/Makefile new file mode 100644 index 0000000..635f65a --- /dev/null +++ b/src/Makefile @@ -0,0 +1,61 @@ +prefix=/usr +includedir=$(prefix)/include +libdir=$(prefix)/lib + +CFLAGS ?= -g -fomit-frame-pointer -O2 +CFLAGS += -Wall -I. -fPIC +SO_CFLAGS=-shared $(CFLAGS) +L_CFLAGS=$(CFLAGS) +LINK_FLAGS= +LINK_FLAGS+=$(LDFLAGS) +ENABLE_SHARED ?= 1 + +soname=liburing.so.1 +minor=0 +micro=1 +libname=$(soname).$(minor).$(micro) +all_targets += liburing.a + +ifeq ($(ENABLE_SHARED),1) +all_targets += $(libname) +endif + +all: $(all_targets) + +liburing_srcs := io_uring.c syscall.c + +liburing_objs := $(patsubst %.c,%.ol,$(liburing_srcs)) +liburing_sobjs := $(patsubst %.c,%.os,$(liburing_srcs)) + +$(liburing_objs) $(liburing_sobjs): io_uring.h + +%.os: %.c + $(CC) $(SO_CFLAGS) -c -o $@ $< + +%.ol: %.c + $(CC) $(L_CFLAGS) -c -o $@ $< + +AR ?= ar +RANLIB ?= ranlib +liburing.a: $(liburing_objs) + rm -f liburing.a + $(AR) r liburing.a $^ + $(RANLIB) liburing.a + +$(libname): $(liburing_sobjs) liburing.map + $(CC) $(SO_CFLAGS) -Wl,--version-script=liburing.map -Wl,-soname=$(soname) -o $@ $(liburing_sobjs) $(LINK_FLAGS) + +install: $(all_targets) + install -D -m 644 io_uring.h $(includedir)/io_uring.h + install -D -m 644 liburing.a $(libdir)/liburing.a +ifeq ($(ENABLE_SHARED),1) + install -D -m 755 $(libname) $(libdir)/$(libname) + ln -sf $(libname) $(libdir)/$(soname) + ln -sf $(libname) $(libdir)/liburing.so +endif + +$(liburing_objs): liburing.h + +clean: + rm -f $(all_targets) $(liburing_objs) $(liburing_sobjs) $(soname).new + rm -f *.so* *.a *.o diff --git a/src/barrier.h b/src/barrier.h new file mode 100644 index 0000000..0fd5c39 --- /dev/null +++ b/src/barrier.h @@ -0,0 +1,16 @@ +#ifndef LIBURING_BARRIER_H +#define LIBURING_BARRIER_H + +#if defined(__x86_64) +#define read_barrier() __asm__ __volatile__("lfence":::"memory") +#define write_barrier() __asm__ __volatile__("sfence":::"memory") +#else +/* + * Add arch appropriate definitions. Be safe and use full barriers for + * archs we don't have support for. + */ +#define read_barrier() __sync_synchronize() +#define write_barrier() __sync_synchronize() +#endif + +#endif diff --git a/src/io_uring.c b/src/io_uring.c new file mode 100644 index 0000000..52b3553 --- /dev/null +++ b/src/io_uring.c @@ -0,0 +1,193 @@ +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/mman.h> +#include <unistd.h> +#include <errno.h> +#include <string.h> + +#include "io_uring.h" +#include "liburing.h" +#include "barrier.h" + +/* + * Return an IO completion, waiting for it it necessary. + */ +int io_uring_get_completion(int fd, struct io_uring_cq *cq, + struct io_uring_event **ev_ptr) +{ + const unsigned mask = *cq->kring_mask; + struct io_uring_event *ev = NULL; + unsigned head; + int ret; + + head = *cq->khead; + do { + read_barrier(); + if (head != *cq->ktail) { + ev = &cq->events[head & mask]; + break; + } + ret = io_uring_enter(fd, 0, 1, IORING_ENTER_GETEVENTS); + if (ret < 0) + return -errno; + } while (1); + + if (ev) { + *cq->khead = head + 1; + write_barrier(); + } + + *ev_ptr = ev; + return 0; +} + +/* + * Submit iocbs acquired from io_uring_get_iocb() to the kernel. + * + * Returns number of iocbs submitted + */ +int io_uring_submit(int fd, struct io_uring_sq *sq) +{ + const unsigned mask = *sq->kring_mask; + unsigned ktail, ktail_next, submitted; + + /* + * If we have pending IO in the kring, submit it first + */ + read_barrier(); + if (*sq->khead != *sq->ktail) { + submitted = *sq->kring_entries; + goto submit; + } + + if (sq->iocb_head == sq->iocb_tail) + return 0; + + /* + * Fill in iocbs that we have queued up, adding them to the kernel ring + */ + submitted = 0; + ktail = ktail_next = *sq->ktail; + while (sq->iocb_head < sq->iocb_tail) { + ktail_next++; + read_barrier(); + if (ktail_next == *sq->khead) + break; + + sq->array[ktail & mask] = sq->iocb_head & mask; + ktail = ktail_next; + + sq->iocb_head++; + submitted++; + } + + if (!submitted) + return 0; + + if (*sq->ktail != ktail) { + write_barrier(); + *sq->ktail = ktail; + write_barrier(); + } + +submit: + return io_uring_enter(fd, submitted, 0, IORING_ENTER_GETEVENTS); +} + +/* + * Return an iocb 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 iocb, or NULL if we're full. + */ +struct io_uring_iocb *io_uring_get_iocb(struct io_uring_sq *sq) +{ + unsigned next = sq->iocb_tail + 1; + struct io_uring_iocb *iocb; + + /* + * All iocbs are used + */ + if (next - sq->iocb_head > *sq->kring_entries) + return NULL; + + iocb = &sq->iocbs[sq->iocb_tail & *sq->kring_mask]; + sq->iocb_tail = next; + return iocb; +} + +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; + void *ptr; + int ret; + + sq->ring_sz = p->sq_off.array + p->sq_entries * sizeof(unsigned); + ptr = mmap(0, sq->ring_sz, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_SQ_RING); + if (ptr == MAP_FAILED) + return -errno; + sq->khead = ptr + p->sq_off.head; + sq->ktail = ptr + p->sq_off.tail; + sq->kring_mask = ptr + p->sq_off.ring_mask; + sq->kring_entries = ptr + p->sq_off.ring_entries; + sq->kflags = ptr + p->sq_off.flags; + sq->kdropped = ptr + p->sq_off.dropped; + sq->array = ptr + p->sq_off.array; + + size = p->sq_entries * sizeof(struct io_uring_iocb); + sq->iocbs = mmap(0, size, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_POPULATE, fd, + IORING_OFF_IOCB); + if (sq->iocbs == MAP_FAILED) { + ret = -errno; +err: + munmap(sq->khead, sq->ring_sz); + return ret; + } + + cq->ring_sz = p->cq_off.events + p->cq_entries * sizeof(struct io_uring_event); + ptr = mmap(0, cq->ring_sz, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_CQ_RING); + if (ptr == MAP_FAILED) { + ret = -errno; + munmap(sq->iocbs, p->sq_entries * sizeof(struct io_uring_iocb)); + goto err; + } + cq->khead = ptr + p->cq_off.head; + cq->ktail = ptr + p->cq_off.tail; + cq->kring_mask = ptr + p->cq_off.ring_mask; + cq->kring_entries = ptr + p->cq_off.ring_entries; + cq->koverflow = ptr + p->cq_off.overflow; + cq->events = ptr + p->cq_off.events; + return fd; +} + +/* + * Returns -1 on error, or an 'fd' on success. On success, 'sq' and 'cq' + * contain the necessary information to read/write to the rings. + */ +int io_uring_queue_init(unsigned entries, struct io_uring_params *p, + struct iovec *iovecs, struct io_uring_sq *sq, + struct io_uring_cq *cq) +{ + int fd; + + fd = io_uring_setup(entries, iovecs, p); + if (fd < 0) + return fd; + + memset(sq, 0, sizeof(*sq)); + memset(cq, 0, sizeof(*cq)); + return io_uring_mmap(fd, p, sq, cq); +} + +void io_uring_queue_exit(int fd, struct io_uring_sq *sq, struct io_uring_cq *cq) +{ + munmap(sq->iocbs, *sq->kring_entries * sizeof(struct io_uring_iocb)); + munmap(sq->khead, sq->ring_sz); + munmap(cq->khead, cq->ring_sz); + close(fd); +} diff --git a/src/io_uring.h b/src/io_uring.h new file mode 100644 index 0000000..7dd2112 --- /dev/null +++ b/src/io_uring.h @@ -0,0 +1,115 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * 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> + +/* + * IO submission data structure + */ +struct io_uring_iocb { + __u8 opcode; + __u8 flags; + __u16 ioprio; + __s32 fd; + __u64 off; + union { + void *addr; + __u64 __pad; + }; + __u32 len; + union { + __kernel_rwf_t rw_flags; + __u32 __resv; + }; +}; + +/* + * io_uring_setup() flags + */ +#define IORING_SETUP_IOPOLL (1 << 0) /* io_context is polled */ +#define IORING_SETUP_FIXEDBUFS (1 << 1) /* IO buffers are fixed */ +#define IORING_SETUP_SQTHREAD (1 << 2) /* Use SQ thread */ +#define IORING_SETUP_SQWQ (1 << 3) /* Use SQ workqueue */ +#define IORING_SETUP_SQPOLL (1 << 4) /* SQ thread polls */ + +#define IORING_OP_READ 1 +#define IORING_OP_WRITE 2 +#define IORING_OP_FSYNC 3 +#define IORING_OP_FDSYNC 4 +#define IORING_OP_READ_FIXED 5 +#define IORING_OP_WRITE_FIXED 6 + +/* + * IO completion data structure + */ +struct io_uring_event { + __u64 index; /* what iocb this event came from */ + __s32 res; /* result code for this event */ + __u32 flags; +}; + +/* + * io_uring_event->flags + */ +#define IOEV_FLAG_CACHEHIT (1 << 0) /* IO did not hit media */ + +/* + * 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_IOCB 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 resv[3]; +}; + +#define IORING_SQ_NEED_WAKEUP (1 << 0) /* needs io_uring_enter wakeup */ + +struct io_cqring_offsets { + __u32 head; + __u32 tail; + __u32 ring_mask; + __u32 ring_entries; + __u32 overflow; + __u32 events; + __u32 resv[4]; +}; + +/* + * io_uring_enter(2) flags + */ +#define IORING_ENTER_GETEVENTS (1 << 0) + +/* + * 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; + __u16 sq_thread_cpu; + __u16 resv[9]; + struct io_sqring_offsets sq_off; + struct io_cqring_offsets cq_off; +}; + +#endif diff --git a/src/liburing.h b/src/liburing.h new file mode 100644 index 0000000..454591a --- /dev/null +++ b/src/liburing.h @@ -0,0 +1,57 @@ +#ifndef LIB_URING_H +#define LIB_URING_H + +#include <sys/uio.h> +#include "io_uring.h" + +/* + * 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_iocb *iocbs; + + unsigned iocb_head; + unsigned iocb_tail; + + size_t ring_sz; +}; + +struct io_uring_cq { + unsigned *khead; + unsigned *ktail; + unsigned *kring_mask; + unsigned *kring_entries; + unsigned *koverflow; + struct io_uring_event *events; + + size_t ring_sz; +}; + +/* + * System calls + */ +extern int io_uring_setup(unsigned entries, struct iovec *iovecs, + struct io_uring_params *p); +extern int io_uring_enter(unsigned fd, unsigned to_submit, + unsigned min_complete, unsigned flags); + +/* + * Library interface + */ +extern int io_uring_queue_init(unsigned entries, struct io_uring_params *p, + struct iovec *iovecs, struct io_uring_sq *sq, struct io_uring_cq *cq); +extern void io_uring_queue_exit(int fd, struct io_uring_sq *sq, + struct io_uring_cq *cq); +extern int io_uring_get_completion(int fd, struct io_uring_cq *cq, + struct io_uring_event **ev_ptr); +extern int io_uring_submit(int fd, struct io_uring_sq *sq); +extern struct io_uring_iocb *io_uring_get_iocb(struct io_uring_sq *sq); + +#endif diff --git a/src/liburing.map b/src/liburing.map new file mode 100644 index 0000000..ef48835 --- /dev/null +++ b/src/liburing.map @@ -0,0 +1,11 @@ +LIBURING_0.1 { + global: + io_uring_queue_init; + io_uring_queue_exit; + io_uring_get_completion; + io_uring_submit; + io_uring_get_iocb; + local: + *; + +}; diff --git a/src/syscall.c b/src/syscall.c new file mode 100644 index 0000000..eafdd39 --- /dev/null +++ b/src/syscall.c @@ -0,0 +1,31 @@ +/* + * Will go away once libc support is there + */ +#include <unistd.h> +#include <sys/syscall.h> +#include <sys/uio.h> +#include "io_uring.h" + +#if defined(__x86_64) +#ifndef __NR_sys_io_uring_setup +#define __NR_sys_io_uring_setup 335 +#endif +#ifndef __NR_sys_io_uring_enter +#define __NR_sys_io_uring_enter 336 +#endif +#else +#error "Arch not supported yet" +#endif + +int io_uring_setup(unsigned int entries, struct iovec *iovecs, + struct io_uring_params *p) +{ + return syscall(__NR_sys_io_uring_setup, entries, iovecs, p); +} + +int io_uring_enter(int fd, unsigned int to_submit, unsigned int min_complete, + unsigned int flags) +{ + return syscall(__NR_sys_io_uring_enter, fd, to_submit, min_complete, + flags); +} diff --git a/test/io_uring-test.c b/test/io_uring-test.c new file mode 100644 index 0000000..d945f48 --- /dev/null +++ b/test/io_uring-test.c @@ -0,0 +1,90 @@ +/* + * Simple app that demonstrates how to setup an io_uring interface, + * submit and complete IO against it, and then tear it down. + * + * gcc -Wall -O2 -D_GNU_SOURCE -o io_uring-test io_uring-test.c -luring + */ +#include <stdio.h> +#include <fcntl.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include "../src/liburing.h" + +int main(int argc, char *argv[]) +{ + struct io_uring_params p; + struct io_uring_sq sq; + struct io_uring_cq cq; + int i, fd, ring_fd, ret, pending, done; + struct io_uring_iocb *iocb; + struct io_uring_event *ev; + off_t offset; + void *buf; + + if (argc < 2) { + printf("%s: file\n", argv[0]); + return 1; + } + + memset(&p, 0, sizeof(p)); + p.flags = IORING_SETUP_IOPOLL; + + ring_fd = io_uring_queue_init(4, &p, NULL, &sq, &cq); + if (ring_fd < 0) { + fprintf(stderr, "queue_init: %s\n", strerror(-ring_fd)); + return 1; + } + + fd = open(argv[1], O_RDONLY | O_DIRECT); + if (fd < 0) { + perror("open"); + return 1; + } + + if (posix_memalign(&buf, 4096, 4096)) + return 1; + + offset = 0; + do { + iocb = io_uring_get_iocb(&sq); + if (!iocb) + break; + iocb->opcode = IORING_OP_READ; + iocb->flags = 0; + iocb->ioprio = 0; + iocb->fd = fd; + iocb->off = offset; + iocb->addr = buf; + iocb->len = 4096; + offset += 4096; + } while (1); + + ret = io_uring_submit(ring_fd, &sq); + if (ret < 0) { + fprintf(stderr, "io_uring_submit: %s\n", strerror(-ret)); + return 1; + } + + done = 0; + pending = ret; + for (i = 0; i < pending; i++) { + ev = NULL; + ret = io_uring_get_completion(ring_fd, &cq, &ev); + if (ret < 0) { + fprintf(stderr, "io_uring_get_completion: %s\n", strerror(-ret)); + return 1; + } + + done++; + if (ev->res != 4096) { + fprintf(stderr, "ret=%d, wanted 4096\n", ev->res); + return 1; + } + } + + printf("Submitted=%d, completed=%d\n", pending, done); + close(fd); + io_uring_queue_exit(ring_fd, &sq, &cq); + return 0; +} |