This patch provides basic protection against damage resulting from
differently compiled servers blindly copying tables to one another.
In every getsysinfo() call, the caller is provided with the expected
size of the requested data structure. The callee fails the call if
the expected size does not match the data structure's actual size.
VFS CHANGES:
- dmap table no longer statically initialized in VFS
- Dropped FSSIGNON svrctl call no longer used by INET
INET CHANGES:
- INET announces its presence to VFS just like any other driver
RS CHANGES:
- The boot image dev table contains all the data to initialize VFS' dmap table
- RS interface supports asynchronous up and update operations now
- RS interface extended to support driver style and flags
SYSLIB CHANGES:
- DS calls to publish / retrieve labels consider endpoints instead of u32_t.
VFS CHANGES:
- mapdriver() only adds an entry in the dmap table in VFS.
- dev_up() is only executed upon reception of a driver up event.
INET CHANGES:
- INET no longer searches for existing drivers instances at startup.
- A newtwork driver is (re)initialized upon reception of a driver up event.
- Networking startup is now race-free by design. No need to waste 5 seconds
at startup any more.
DRIVER CHANGES:
- Every driver publishes driver up events when starting for the first time or
in case of restart when recovery actions must be taken in the upper layers.
- Driver up events are published by drivers through DS.
- For regular drivers, VFS is normally the only subscriber, but not necessarily.
For instance, when the filter driver is in use, it must subscribe to driver
up events to initiate recovery.
- For network drivers, inet is the only subscriber for now.
- Every VFS driver is statically linked with libdriver, every network driver
is statically linked with libnetdriver.
DRIVER LIBRARIES CHANGES:
- Libdriver is extended to provide generic receive() and ds_publish() interfaces
for VFS drivers.
- driver_receive() is a wrapper for sef_receive() also used in driver_task()
to discard spurious messages that were meant to be delivered to a previous
version of the driver.
- driver_receive_mq() is the same as driver_receive() but integrates support
for queued messages.
- driver_announce() publishes a driver up event for VFS drivers and marks
the driver as initialized and expecting a DEV_OPEN message.
- Libnetdriver is introduced to provide similar receive() and ds_publish()
interfaces for network drivers (netdriver_announce() and netdriver_receive()).
- Network drivers all support live update with no state transfer now.
KERNEL CHANGES:
- Added kernel call statectl for state management. Used by driver_announce() to
unblock eventual callers sendrecing to the driver.
IS:
- do not use p_getfrom_e for a process that is sending
- register with TTY only function keys that are used
- various header and formatting fixes
- proper shutdown code
TTY:
- restore proper Ctrl+F1 dump contents
isofs:
- don't even try to call sys_exit()
- all macros in consts.h that depend on NR_TASKS replaced by a FP_BLOCKED_ON_*
- fp_suspended removed and replaced by fp_blocked_on. Testing whether a process
is supended is qeual to testing whether fp_blocked_on is FP_BLOCKED_ON_NONE or
not
- fp_task is valid only if fp_blocked_on == FP_BLOCKED_ON_OTHER
- no need of special values that do not colide with valid and special endpoints
since they are not used as endpoints anymore
- suspend only takes FP_BLOCKED_ON_* values not endpoints anymore
- suspend(task) replaced by wait_for(task) which sets fp_task so we remember who
are we waiting for and suspend sets fp_blocked_on to FP_BLOCKED_ON_OTHER to
signal that we are waiting for some other process
- some functions should take endpoint_t instead of int, fixed
'who', indicating caller number in pm and fs and some other servers, has
been removed in favour of 'who_e' (endpoint) and 'who_p' (proc nr.).
In both PM and FS, isokendpt() convert endpoints to process slot
numbers, returning OK if it was a valid and consistent endpoint number.
okendpt() does the same but panic()s if it doesn't succeed. (In PM,
this is pm_isok..)
pm and fs keep their own records of process endpoints in their proc tables,
which are needed to make kernel calls about those processes.
message field names have changed.
fs drivers are endpoints.
fs now doesn't try to get out of driver deadlock, as the protocol isn't
supposed to let that happen any more. (A warning is printed if ELOCKED
is detected though.)
fproc[].fp_task (indicating which driver the process is suspended on)
became an int.
PM and FS now get endpoint numbers of initial boot processes from the
kernel. These happen to be the same as the old proc numbers, to let
user processes reach them with the old numbers, but FS and PM don't know
that. All new processes after INIT, even after the generation number
wraps around, get endpoint numbers with generation 1 and higher, so
the first instances of the boot processes are the only processes ever
to have endpoint numbers in the old proc number range.
More return code checks of sys_* functions have been added.
IS has become endpoint-aware. Ditched the 'text' and 'data' fields
in the kernel dump (which show locations, not sizes, so aren't terribly
useful) in favour of the endpoint number. Proc number is still visible.
Some other dumps (e.g. dmap, rs) show endpoint numbers now too which got
the formatting changed.
PM reading segments using rw_seg() has changed - it uses other fields
in the message now instead of encoding the segment and process number and
fd in the fd field. For that it uses _read_pm() and _write_pm() which to
_taskcall()s directly in pm/misc.c.
PM now sys_exit()s itself on panic(), instead of sys_abort().
RS also talks in endpoints instead of process numbers.
. unmap device drivers from dmap when PM signals they are dead
. new null-io function (no_dev_io) to fill in for io functions
of unmapped drivers
. driver (process number) of unmapped drivers is NONE instead of
0 (a valid process number)
IS:
. print mutable flag of dmap table too
FS changes require sync() to be done 'manually' (currently by
reboot/shutdown) at shutdown time; could be caught by SIGTERM in
the future.
