Introduces the CopyFileRange syscall which first appears in Linux 4.5.
Allows copying file content between file descriptors within the kernel
without transferring data to user space. This syscall also allows the
kernel to take advantage of reflinking or other fast copy methods on
supported file systems.
http://man7.org/linux/man-pages/man2/copy_file_range.2.html
Change-Id: Id365f1e5d4d5ddf7159478e3a13084c9576ebd5c
Reviewed-on: https://go-review.googlesource.com/39992
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Right now the process for adding in new constants, errors, or syscalls
for Linux is a pain and unreliable. The scripts are designed to be run
on the target architecture and use the header files installed on the
user's system. This makes it hard to generate files for all the
architectures or to have consistency between users. See golang/go#15282.
This CL fixes this issue by making all of the files for the 11 supported
architectures directly from source checkouts of Linux, glibc, and bluez.
This is done using Docker, the gcc cross-compilers, and qemu emulation.
Previously discussed here:
https://go-review.googlesource.com/c/37589/
A README.md file is also added to explain how all the parts of the build
system work.
In order to get the build working for all the architectures, I made
some changes to the other scripts called from mkall_linux.go:
- Files only used for generating linux code, moved to linux/
- linux/mksysnum.pl supports a specified CC compiler.
- The generated C code in mkerrors.sh changed to avoid a warning
- mkerrors.sh headers changed to fix powerpc64 bug in sys/ioctl.h
- linux/types.go no longer needs to export Ptrace structs in lowercase
Build instructions:
- Host system needs to be x86-64 Linux
- Install Docker (https://docs.docker.com/engine/installation/)
- ./mkall.sh (That's it!!!)
Change-Id: I87067c14442ba12f8d51991349a43a9d73f38ae0
Reviewed-on: https://go-review.googlesource.com/37943
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This CL introduces the Getrandom syscall. Allowing users of
sufficiently new kernels (3.17) to detect when the operating system
lacks enough entropy to generate cryptographic random data. See:
http://man7.org/linux/man-pages/man2/getrandom.2.html
As we have updated the syscall numbers, the Getrandom function can
just be generated normally. The only other change is to mkerrors.sh
to include the GRND_* flags for getrandom from <linux/random.h>.
It is important to note that currently the mkerrors.sh script cannot
actually be run as it has fallen behind the 4.10 kernel. The GRND_*
flags were added manually.
This was originally part of a larger commit that was split up.
See CL: https://go-review.googlesource.com/37570
Change-Id: I464088a9c9f7224abdcdae476b30a4f2f412d9f5
Reviewed-on: https://go-review.googlesource.com/37589
Reviewed-by: Matt Layher <mdlayher@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Matt Layher <mdlayher@gmail.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This fixes I8dc87401bb1025c2404e7304ecc4561edd67a452, which failed to
include the changes for s390x and sparc64, breaking the build for them.
Change-Id: I4899350580c36e4efbec9801345b5e32d624c849
Reviewed-on: https://go-review.googlesource.com/31185
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This commit adds linux/s390x support to the unix package. It is
based on the changes made to the syscall package in
https://golang.org/cl/20961/. It also adds mkpost.go which is
used to cleanup the API generated by cgo -godefs.
The biggest departure that is made with the syscall package is
the use of the -fsigned-char flag to force signed chars. We
couldn't do this in the syscall package because of the need to
maintain compatibility with the gccgo implementation of the syscall
package (gccgo has supported s390x for a longer time than the Go
toolchain). The unix package does not have this constraint.
Using the -fsigned-char flag makes the API look more like the one
generated on amd64 and arm64 and also more consistent with itself
(the syscall package represents chars using both int8 and uint8
types, the sys package will only ever use int8). Unfortunately it
also means that applications transitioning from the syscall package
to the unix package will see a different API on s390x which might
be confusing. I think the tradeoff is worth it though.
Change-Id: I40b90c18ed787e74ba7a2ebd004bd6bd1ba6279a
Reviewed-on: https://go-review.googlesource.com/23045
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Derek McGowan