This is very basic and doesn't support many features. Instead
of describing what it *doesn't* support, I'll describe what I
have tested:
1. Public key authentication (password is not supported)
2. Single command execution
3. PTY-less interactive bash shell (/bin/sh doesn't work)
4. Multi-user (i.e you can ssh as 'anon' as well as root)
Step one of moving DesktopServices::open handling out of process. This
makes it easier to do things like read in associations for which program
opens which files or protocols. This gives users the ability to modify
the associations without having to rebuild :^)
It didn't feel right to have a "DHCPClient" in a "Servers" directory.
Rename this to Services to better reflect the type of programs we'll
be putting in there.
Ultimately we should not panic just because we can't fully commit a VM
region (by populating it with physical pages.)
This patch handles some of the situations where commit() can fail.
This caused us to report one purged page per occurrence of the shared
zero page in a purgeable memory region, despite it being a no-op.
Thanks to Sergey for spotting the bad assertion removal that led to
this being found!
This patch adds PageFaultResponse::OutOfMemory which informs the fault
handler that we were unable to allocate a necessary physical page and
cannot continue.
In response to this, the kernel will crash the current process. Because
we are OOM, we can't symbolicate the crash like we normally would
(since the ELF symbolication code needs to allocate), so we also
communicate to Process::crash() that we're out of memory.
Now we can survive "allocate 300 MB" (only the allocate process dies.)
This is definitely not perfect and can easily end up killing a random
innocent other process who happened to allocate one page at the wrong
time, but it's a *lot* better than panicking on OOM. :^)
This function has a lot of callers that don't bother checking if it
returns successfully or not. We'll need to handle failure in a bunch
of places and then we can remove this assertion.
The detection works very similarly to how we detect a mouse wheel, just
another magical sequence of "set sample rate" requests to the mouse
followed by an ID check.
If we OOM during a CoW fault and fail to allocate a new page for the
writing process, just leave the original VMObject alone so everyone
else can keep using it.
Since a Region is basically a view into a potentially larger VMObject,
it was always necessary to include the Region starting offset when
accessing its underlying physical pages.
Until now, you had to do that manually, but this patch adds a simple
Region::physical_page() for read-only access and a physical_page_slot()
when you want a mutable reference to the RefPtr<PhysicalPage> itself.
A lot of code is simplified by making use of this.
Previously we blindly just called update_next_timer_due() when
ever we modified the timer list. Since we know the list is sorted
this is a bit wasteful, and we can do better.
This change refactors the code so we only update the next due time
when necessary. In places where it was possible the code was modified
to directly modify the next due time, instead of having to go to the
front of the list to fetch it.
The public consumers of the timer API shouldn't need to know
the how timer id's are tracked internally. Expose a typedef
instead to allow the internal implementation to be protected
from potential churn in the future.
It's also just good API design.
Utilize the new Thread::wait_on timeout parameter to implement
timeout support for FUTEX_WAIT.
As we compute the relative time from the user specified absolute
time, we try to delay that computation as long as possible before
we call into Thread::wait_on(..). To enable this a small bit of
refactoring was done pull futex_queue fetching out and timeout fetch
and calculation separation.
This change plumbs a new optional timeout option to wait_on.
The timeout is enabled by enqueing a timer on the timer queue
while we are waiting. We can then see if we were woken up or
timed out by checking if we are still on the wait queue or not.
The current API of add_timer makes it hard to use as
you are forced to do a bunch of time arithmetic at the
caller. Ideally we would have overloads for common time
types like timespec or timeval to keep the API as straight
forward as possible. This change moves us in that direction.
While I'm here, we should really also use the machines actual
ticks per second, instead of the OPTIMAL_TICKS_PER_SECOND_RATE.
This is a special case that was previously not implemented.
The idea is that you can dispatch a signal to all other processes
the calling process has access to.
There was some minor refactoring to make the self signal logic
into a function so it could easily be easily re-used from do_killall.
Previously, when returning from a pthread's start_routine, we would
segfault. Now we instead implicitly call pthread_exit as specified in
the standard.
pthread_create now creates a thread running the new
pthread_create_helper, which properly manages the calling and exiting
of the start_routine supplied to pthread_create. To accomplish this,
the thread's stack initialization has been moved out of
sys$create_thread and into the userspace function create_thread.
