Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

The bsd specific ones are nenumbered to avoid clashes.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Since most SOL_* macros are equivalent to the IPPROTO_* defines, only one
define needs to be changed.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Move them to a common include file.

Since they're defined externally, there is no real conflict.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

thread::destroy() had a "FIXME" comment:
// FIXME: we have a problem in case of a race between join() and the
// thread's completion. Here we can see _joiner==0 and not notify
// anyone, but at the same time join() decided to go to sleep (because
// status is not yet status::terminated) and we'll never wake it.

This is indeed a bug, which Glauber discovered was hanging the
tst-threadcomplete.so test once in a while - the test sometimes hangs
with one thread in the "terminated" state (waiting for someone to join
it), and a second thread waiting in join() but missed the other thread's
termination event.

The solution works like this:

join() uses a CAS to set itself as the _joiner. If it succeeded, it
waits like before for the status to become "terminated". But if the CAS
failed, it means a concurrent destroy() call beat us at the race, and we
can just return from join().

destroy() checks (with a CAS) if _joiner was already set - if so we need
to wake this thread just like in the original code. But if _joiner was
not yet set, either there is no-one doing join(), or there's a concurrent
join() call that will soon return (this is what the joiner does when it
loses the CAS race). In this case, all we need to do is to set the status
to "terminated" - and we must do it through a _detached_state we saved
earlier, because if join() already returned the thread may already be
deleted).

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

wake_with(action) was implemented using thread_handle, as the following:

thread_handle h(handle());
action();
h.wake();

This implementation is wrong: It only takes the RCU lock (which prevents
the destruction of _detached_state) during h.wake(), meaning that if the
thread is not sleeping, and action() causes it to exit, _detached_state
may also be destructed, and h.wake() will crash.

thread_handle is simply not needed for wake_with(), and was designed
with a completely different use case in mind (long-term holding of a
thread handler). We just need to use, in-line, the appropriate rcu
lock which keeps _detached_state alive. The resulting code is even
simpler, and nicely parallels the existing code of wake().

This patch fixes a real bug, but unfortunately we don't have a concrete
test-case which it is known to fix.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Add a new lock, "rcu_read_lock_in_preempt_disabled", which is exactly
like rcu_read_lock but assuming that preemption is already disabled.
Because all our rcu_read_lock does is to disable preemption, the new
lock type currently does absolutely nothing - but in some future
implementation of RCU it might need to do something.

We'll use the new lock type in the following patch, as an optimization
over the regular rcu_read_lock.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Context: going to wait with irqs_disabled is a call for disaster.  While it is
true that not every time we call wait we actually end up waiting, that should
be an invalid call, due to the times we may wait. Because of that, it would
be good to express that nonsense in an assertion.

There is however, places we sleep with irqs disabled currently. Although they
are technically safe, because we implicitly enable interrupts, they end up
reaching wait() in a non-safe state. That happens in the page fault handler.
Explicitly enabling interrupts will allow us to test for valid / invalid wait
status.

With this test applied, all tests in our whitelist still passes.

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Add a mmu::is_page_aligned() helper function and use it to get rid of
open-coded checks.

Reviewed-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

 - It's compiled out when mode=release.
 - Uses an assert() for issuing the assert.
 - Has a printf-like semantics.

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

 - Add -DNDEBUG to the compiler flags when mode!=debug.
 - Prevent assert() from compiling out in kernel when mode=release

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Add the missing #infdef X #define X protection to include/api/assert.h

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Simplify core/mmu.cc and make it more portable by moving the page fault
handler to arch/x64/mmu.cc.  There's more arch specific code in
core/mmu.cc that should be also moved.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Make vma constructors more strongly typed by using the addr_range type.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Separate the common vma code to an abstract base class that's inherited
by anon_vma and file_vma.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

We suddenly stop propagating the exception frame down the vma_fault path.
There is no reason not to propagate it further, aside from the fact that
currently there are no users. However, aside from the fact that it presents a
more consistent frame passing, I intend to use it for the JVM balloon.

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

This patch fixes two bugs in shared-object finalization, i.e., running
its static destructors before it is unloaded. The bugs were seen when
osv::run()ing a test program using libboost_unit_test_framework-mt.so,
which crashed after the test program finished.

The two related bugs were:

1. We need to call the module's destructors (run_fini_funcs()) *before*
   removing it from the module list, otherwise the destructors will not
   be able to call functions from this module! (we got a symbol not
   found error in the destructor).

2. We need to unload the modules needed by this module *before* unloading
   this module, not after like was (implictly) done until now.
   This makes sense because of symmetry (during a module load, the needed
   modules are loaded after this one), but also practically: a needed
   module's destructor (in our case, boost unit test framework) might refer
   to objects in the needing module (in our case, the test program),
   so we cannot call the needed module's destructor after we've already
   unloaded the needing module.

Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Currently, namei() does vget() unconditionally if no dentry is found.
This is wrong because the path can be a hard link that points to a vnode
that's already in memory.

To fix the problem:

  - Use inode number as part of the hash in vget()

  - Use vn_lookup() in vget() to make sure we have one vnode in memory
    per inode number.

  - Push the vget() calls down to individual filesystems and make
    VOP_LOOKUP return an vnode

Changes since v2:
  - v1 dropped lock in vn_lookup, thus assert that vnode_lock is held.

Changes since v3:
  - Fix lock ordering issue in dentry_lookup. The lock respective to the parent
node must be acquired before dentry_lookup and released after the process is
done. Otherwise, a second thread looking up for the same dentry may take the
'NULL' path incorrectly.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

As ref() is now never called, we can remove the reference counter and
make unref() unconditional.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

One problem with wake() is, if the thread that it is waking can cuncurrently
exit, that it may touch freed memory belonging to the thread structure.

Fix by separating the state that wake() touches into a detached_state
structure, and free that using rcu.

Add a thread_handle class that references only this detached state, and
accesses it via rcu.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Makes it much easier to use.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

rcu_read_lock disables preemption, but this is an implementation detail
and users should not make use of it.

Add preempt_lock_in_rcu that takes advantage of the implementation detail
and does nothing, but allows users to explicitly disable preemption.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

When seeing this flag, pages fault in should not be filled with zeroes or any
other patterns, and should rather be just left alone in whatever state we find
them at.

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

This reverts commit e4aad1ba.

It causes tst-vfs.so to just hang.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

I needed to call detach in a test code of mine, and this is isn't implemented.
The code I wrote to use it may or may not stay in the end, but nevertheless,
let's implement it.

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Linux uses a 32-bit integer for pid_t, so let's do it as well. This is because
there are function in which we have to return our id back to the application.
One application is gettid, that we already have in the tree.

Theoretically, we could come up with a mapping between our 64-bit id and the
Linux one, but since we have to maintain the mapping anyway, we might as well
just use the Linux pids as our default IDs. The max size for that is 32-bit. It
is not enough if we're just allocating pids by bumping the counter, but again,
since we will have to maintain the bitmaps, 32-bit will allow us as much as 4
billion PIDs.

avi: remove unneeded #include

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Right now we are taking a clock measure very early for cpu initialization.
That forces an unnecessary dependency between sched and clock initializations.

Since that lock is used to determine for how long the cpu has been running, we
can initialize the runtime later, when we init the idle thread. Nothing should
be running before it. After doing this, we can move the sched initialization
a bit earlier.

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Currently, namei() does vget() unconditionally if no dentry is found.
This is wrong because the path can be a hard link that points to a vnode
that's already in memory.

To fix the problem:

  - Use inode number as part of the hash in vget()

  - Use vn_lookup() in vget() to make sure we have one vnode in memory
    per inode number.

  - Push the vget() calls down to individual filesystems and make
    VOP_LOOKUP return an vnode

  - Drop lock in vn_lookup() and assert that vnode_lock is held.

Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
Signed-off-by: Raphael S. Carvalho <raphaelsc@cloudius-systems.com>
Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Prior to 65ccda4c (net: use a file derived class for sockets
 (socket_file)), ioctl()s for socket were directed to linux_ioctl_socket()
and thence to soo_ioctl().  However that commit short-circuited
linux_ioctl_socket() out and dipatched directly to what was previously
known as soo_ioctl() (and became socket_file::ioctl()).  The caused
interface enumeration ioctl()s to fail, for example in Cassandra.

Fix by bringing back the previous behaviour.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

A list can be slow to search for an element if we have many threads. Even under
normal load, the number of threads we span may not be classified as huge, but it
is not tiny either.

Change it to a map so we can implement functions that operate on a given thread
without that much overhead - O(1) for the common case. Note that ideally we would
use an unordered_set, that doesn't require an extra key. However, that would also
mean that the key is implicit and set to be of type key_type&. Threads are not very
lightweight to create for search purposes, so we go for a id-as-key approach.

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

no users in tree.

Signed-off-by: Glauber Costa <glommer@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

This restore the original behavior of osv::run in place before the mkfs.so and
cpiod.so split committed a day ago.

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Nadav Har'El <nyh@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>

Everyone is now overriding file's virtual functions; we can make them
pure virtual and remove fileops completely.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Unused.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>