Irqs can now touch runqueues and do async wakeups. This necessitated
that we implement all wake up wait and runqueue locking work with irqs.
All this, assumes that in an SMP setup we may have cross-cpu wake ups,
runqueue manipulation. If we later decide that we only wake up threads
in the current container, (and lock containers to cpus) we won't really
need spinlocks, or irq disabling anymore. The current set up might be
trivially less responsive, but is more flexible.
l4_capability_control works well for almost all system calls
using a buffer pointer to the capability that it operates on.
Only for sharing/granting of capability lists, it is yet to be
decided how to provide a grant target id.
A 16-bit device number or id further distinguishes a device on the
system in addition to the device type. This is meant to be used for
the very first identification of the device for further probing. Any
further info is available by userspace mapping and probing.
Modifying task_virt_to_page() so that it takes into account page
protections. If mm0 writes to a task page that is meant to be
read-only, (e.g. the zero page) the design is broken.
Every access to a task's page will take the page fault route,
and the page fault handler will return the page instead of 0.
Removed dependency on hard-coded pager id. Pager id is now passed
as an environment string `pagerid' to tasks. Alternatively, this
could take space in the utcb of each task.
