This step would ideally not have been necessary (increases amount of
refactoring and templates necessary, which in turn increases build
times), but it gives us a couple of nice properties:
- SpinlockProtected inside Singleton (a very common combination) can now
obtain any lock rank just via the template parameter. It was not
previously possible to do this with SingletonInstanceCreator magic.
- SpinlockProtected's lock rank is now mandatory; this is the majority
of cases and allows us to see where we're still missing proper ranks.
- The type already informs us what lock rank a lock has, which aids code
readability and (possibly, if gdb cooperates) lock mismatch debugging.
- The rank of a lock can no longer be dynamic, which is not something we
wanted in the first place (or made use of). Locks randomly changing
their rank sounds like a disaster waiting to happen.
- In some places, we might be able to statically check that locks are
taken in the right order (with the right lock rank checking
implementation) as rank information is fully statically known.
This refactoring even more exposes the fact that Mutex has no lock rank
capabilites, which is not fixed here.
From now on, we don't allow jailed processes to open all device nodes in
/dev, but only allow jailed processes to open /dev/full, /dev/zero,
/dev/null, and various TTY and PTY devices (and not including virtual
consoles) so we basically restrict applications to what they can do when
they are in jail.
The motivation for this type of restriction is to ensure that even if a
remote code execution occurred, the damage that can be done is very
small.
We also don't restrict reading and writing on device nodes that were
already opened, because that limit seems not useful, especially in the
case where we do want to provide an OpenFileDescription to such device
but nothing further than that.
The ProcFS is an utter mess currently, so let's start move things that
are not related to processes-info. To ensure it's done in a sane manner,
we start by duplicating all /proc/ global nodes to the /sys/kernel/
directory, then we will move Userland to use the new directory so the
old directory nodes can be removed from the /proc directory.
Until now, our kernel has reimplemented a number of AK classes to
provide automatic internal locking:
- RefPtr
- NonnullRefPtr
- WeakPtr
- Weakable
This patch renames the Kernel classes so that they can coexist with
the original AK classes:
- RefPtr => LockRefPtr
- NonnullRefPtr => NonnullLockRefPtr
- WeakPtr => LockWeakPtr
- Weakable => LockWeakable
The goal here is to eventually get rid of the Lock* classes in favor of
using external locking.
This was a premature optimization from the early days of SerenityOS.
The eternal heap was a simple bump pointer allocator over a static
byte array. My original idea was to avoid heap fragmentation and improve
data locality, but both ideas were rooted in cargo culting, not data.
We would reserve 4 MiB at boot and only ended up using ~256 KiB, wasting
the rest.
This patch replaces all kmalloc_eternal() usage by regular kmalloc().
We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace!
This was a slightly tedious refactoring that took a long time, so it's
not unlikely that some bugs crept in.
Nevertheless, it does pass basic functionality testing, and it's just
real nice to finally see the same pattern in all contexts. :^)
Previously there was a mix of returning plain strings and returning
explicit string views using `operator ""sv`. This change switches them
all to standardized on `operator ""sv` as it avoids a call to strlen.
