Headers 3 headers related to message registers and utcbs are now merged under
utcb.h in libl4. Some message register definitions used by the kernel are now
moved into kernel's glue/message.h. This avoids the duplication of same
definitions. Also the total number of mregs are now determined by arch-specific
kernel header, which is good.
Modified ipc handling so that from now on the kernel inspects and sets
the sender id if the receiver is receiving from L4_ANYTHREAD. This posed
a security problem since the receiver could not trust the sender for
sender information.
Boot files and tasks are now initialised together. Theads can ask for particular
space and thread ids, if they're unused. This enables us to get predefined ids for
known tasks such as the VFS task.
Fixes to README
Other minor fixes.
Previously we had changed the method of setting the ipc tag from l4_ipc() call
argument to being passed as a message register.
- This change was not reflected in l4_ipc() signature as it still had a 3rd argument,
even though ignored.
- l4_set_sender and _set_tag had their arguments wrong way around.
- Previously 5 mrs were passed onto utcb instead of 6, relying on the fact that
l4_ipc tag argument was being passed in r3 directly, this wasnt true anymore
with new convention, but wasn't catered for.
TODO:
- MM0 shouldn't really allocate tids itself, but use ones supplied by C0.
- Sender tid shouldn't really passed by the sender task, but rather by C0. Otherwise
security can be easily breached by user tasks pretending to be other tasks. This
would also save us a message register.
Paging-in requests seem to work.
TODO:
- Remove far/fsr information in pager and abstract away these details in c0.
- Add a npages field to page fault ipc so that multiple pages can be paged-in.
Added routines that check whether a user pointer is accessible by the kernel,
and if not ask the pager to map-in those pages. I haven't implemented yet the
bit that asks the pager for paging-in.
ipc_sendrecv() replaces ipc_sendwait() which was flawed. See ipc_sendrecv() for
how client/server communication works. Tested with page faults where the kernel
does an ipc_sendrecv() to faulty thread's pager and the pager successfully handles
the request, and returns back the result, which effectively restarts the faulty
thread.
Removed previously implemented but untested mechanism of blocking tasks
from doing ipc to certain tasks using certain tags. This is to be considered
for future implementation.
Changed l4id_t type to integer to recognise negative id values like L4_ANYTHREAD.
Added an extremely simple script that cleans and builds everything in right order.
Increased boot pmds by one:
This is due to the fact that if the 1MB initial allocation area of the kernel is
not 1MB-aligned, it is ought to be mapped from the middle of one MB to next,
which requires 2 pmds.
modified: .gdbinit
modified: README
new file: buildall.sh
modified: include/l4/arch/arm/types.h
modified: include/l4/generic/scheduler.h
modified: loader/kernel.S
modified: loader/main.c
modified: loader/mylink.lds
modified: loader/start.axf.S
modified: src/glue/arm/init.c
modified: src/glue/arm/memory.c
modified: tasks/fs0/src/bdev.c
modified: tasks/mm0/include/kdata.h
modified: tasks/mm0/include/vm_area.h
modified: tasks/mm0/src/init.c
modified: tasks/mm0/src/task.c
modified: tools/ksym_to_lds.py
modified: tools/l4-qemu
Previously python hex() would put an extra 'L' after printing out the
value and this would be trimmed in readelf.py. Now it doesn't seem to
do that so the lsd of the number was trimmed. This patch fixes that.