Commit Graph

6 Commits

Author SHA1 Message Date
Ed Schouten
b53b978a6c Complete the CloudABI networking refactoring.
Now that all of the packaged software has been adjusted to either use
Flower (https://github.com/NuxiNL/flower) for making incoming/outgoing
network connections or can have connections injected, there is no longer
need to keep accept() around. It is now a lot easier to write networked
services that are address family independent, dual-stack, testable, etc.

Remove all of the bits related to accept(), but also to
getsockopt(SO_ACCEPTCONN).
2017-08-30 07:30:06 +00:00
Ed Schouten
8212ad9a99 Sync CloudABI compatibility against the latest upstream version (v0.13).
With Flower (CloudABI's network connection daemon) becoming more
complete, there is no longer any need for creating any unconnected
sockets. Socket pairs in combination with file descriptor passing is all
that is necessary, as that is what is used by Flower to pass network
connections from the public internet to listening processes.

Remove all of the kernel bits that were used to implement socket(),
listen(), bindat() and connectat(). In principle, accept() and
SO_ACCEPTCONN may also be removed, but there are still some consumers
left.

Obtained from:	https://github.com/NuxiNL/cloudabi
MFC after:	1 month
2017-08-25 11:01:39 +00:00
Ed Schouten
cea9310d4e Upgrade to the latest sources generated from the CloudABI specification.
The CloudABI specification has had some minor changes over the last half
year. No substantial features have been added, but some features that
are deemed unnecessary in retrospect have been removed:

- mlock()/munlock():

  These calls tend to be used for two different purposes: real-time
  support and handling of sensitive (cryptographic) material that
  shouldn't end up in swap. The former use case is out of scope for
  CloudABI. The latter may also be handled by encrypting swap.

  Removing this has the advantage that we no longer need to worry about
  having resource limits put in place.

- SOCK_SEQPACKET:

  Support for SOCK_SEQPACKET is rather inconsistent across various
  operating systems. Some operating systems supported by CloudABI (e.g.,
  macOS) don't support it at all. Considering that they are rarely used,
  remove support for the time being.

- getsockname(), getpeername(), etc.:

  A shortcoming of the sockets API is that it doesn't allow you to
  create socket(pair)s, having fake socket addresses associated with
  them. This makes it harder to test applications or transparently
  forward (proxy) connections to them.

  With CloudABI, we're slowly moving networking connectivity into a
  separate daemon called Flower. In addition to passing around socket
  file descriptors, this daemon provides address information in the form
  of arbitrary string labels. There is thus no longer any need for
  requesting socket address information from the kernel itself.

This change also updates consumers of the generated code accordingly.
Even though system calls end up getting renumbered, this won't cause any
problems in practice. CloudABI programs always call into the kernel
through a kernel-supplied vDSO that has the numbers updated as well.

Obtained from:	https://github.com/NuxiNL/cloudabi
2017-07-26 06:57:15 +00:00
Ed Schouten
cbf42683f8 Sync in latest vDSOs from upstream.
- Use conditional instruction to simplify the ARMv6 vDSO. This means
  that we no longer perform any branching. In the failure case, we
  simply slide over the assignments of the return values.

  The vDSO could be improved even further by using stmia to do
  assignments in parallel. Unfortunately, the script used to generate
  these is not smart enough for that (yet).

  Spotted by: andrew@.

- Make the style of the i686 vDSO more similar to the others by using
  decimal literals.
2016-09-19 17:31:05 +00:00
Ed Schouten
9bc326d18b Fix badly computed register/stack offset of system call output arguments.
Bugs in the Python code used to generate this vDSO caused us to
miscompute the register numbers/stack offsets at which addresses of the
system call output arguments were stored.

Together with some other patches, this vDSO allows us to make all of the
cloudlibc unit tests pass.

Obtained from:	https://github.com/NuxiNL/cloudabi
2016-09-18 17:23:53 +00:00
Ed Schouten
5e7b54b184 Add very preliminary support for CloudABI for ARMv6.
In order to make CloudABI work on ARMv6, start off by copying over the
sysvec for ARM64 and adjust it to use 32-bit registers. Also add code
for fetching arguments from the stack if needed, as there are fewer
register than on ARM64.

Also import the vDSO that is needed to invoke system calls. This vDSO
uses the intra procedure call register (ip) to store the system call
number. This is a bit simpler than what native FreeBSD does, as FreeBSD
uses r7, while preserving the original r7 into ip.

This sysvec seems to be complete enough to start CloudABI processes.
These processes are capable of linking in the vDSO and are therefore
capable of executing (most?) system calls successfully. Unfortunately,
the biggest show stopper is still that TLS is completely broken:

- The linker used by CloudABI, LLD, still has troubles with some of the
  relocations needed for TLS. See LLVM bug 30218 for more details.

- Whereas FreeBSD uses the tpidruro register for TLS, for CloudABI I
  want to make use of tpidrurw, so that userspace can modify the base
  address directly. This is needed for efficient emulation.
  Unfortunately, this register doesn't seem to be preserved across
  context switches yet.

Obtained from:	https://github.com/NuxiNL/cloudabi (the vDSO)
2016-09-18 11:36:54 +00:00