have malloc/free, alloc_contig/free_contig and mmap/munmap nicely
paired up.
memory uses malloc/free instead of mmap/munmap as it doesn't have
to be contiguous for the ramdisks (and it might help if it doesn't!).
SYSLIB CHANGES:
- SEF framework now supports a new SEF Init request type from RS. 3 different
callbacks are available (init_fresh, init_lu, init_restart) to specify
initialization code when a service starts fresh, starts after a live update,
or restarts.
SYSTEM SERVICE CHANGES:
- Initialization code for system services is now enclosed in a callback SEF will
automatically call at init time. The return code of the callback will
tell RS whether the initialization completed successfully.
- Each init callback can access information passed by RS to initialize. As of
now, each system service has access to the public entries of RS's system process
table to gather all the information required to initialize. This design
eliminates many existing or potential races at boot time and provides a uniform
initialization interface to system services. The same interface will be reused
for the upcoming publish/subscribe model to handle dynamic
registration / deregistration of system services.
VM CHANGES:
- Uniform privilege management for all system services. Every service uses the
same call mask format. For boot services, VM copies the call mask from init
data. For dynamic services, VM still receives the call mask via rs_set_priv
call that will be soon replaced by the upcoming publish/subscribe model.
RS CHANGES:
- The system process table has been reorganized and split into private entries
and public entries. Only the latter ones are exposed to system services.
- VM call masks are now entirely configured in rs/table.c
- RS has now its own slot in the system process table. Only kernel tasks and
user processes not included in the boot image are now left out from the system
process table.
- RS implements the initialization protocol for system services.
- For services in the boot image, RS blocks till initialization is complete and
panics when failure is reported back. Services are initialized in their order of
appearance in the boot image priv table and RS blocks to implements synchronous
initialization for every system service having the flag SF_SYNCH_BOOT set.
- For services started dynamically, the initialization protocol is implemented
as though it were the first ping for the service. In this case, if the
system service fails to report back (or reports failure), RS brings the service
down rather than trying to restart it.
SYSLIB CHANGES:
- SEF must be used by every system process and is thereby part of the system
library.
- The framework provides a receive() interface (sef_receive) for system
processes to automatically catch known system even messages and process them.
- SEF provides a default behavior for each type of system event, but allows
system processes to register callbacks to override the default behavior.
- Custom (local to the process) or predefined (provided by SEF) callback
implementations can be registered to SEF.
- SEF currently includes support for 2 types of system events:
1. SEF Ping. The event occurs every time RS sends a ping to figure out
whether a system process is still alive. The default callback implementation
provided by SEF is to notify RS back to let it know the process is alive
and kicking.
2. SEF Live update. The event occurs every time RS sends a prepare to update
message to let a system process know an update is available and to prepare
for it. The live update support is very basic for now. SEF only deals with
verifying if the prepare state can be supported by the process, dumping the
state for debugging purposes, and providing an event-driven programming
model to the process to react to state changes check-in when ready to update.
- SEF should be extended in the future to integrate support for more types of
system events. Ideally, all the cross-cutting concerns should be integrated into
SEF to avoid duplicating code and ease extensibility. Examples include:
* PM notify messages primarily used at shutdown.
* SYSTEM notify messages primarily used for signals.
* CLOCK notify messages used for system alarms.
* Debug messages. IS could still be in charge of fkey handling but would
forward the debug message to the target process (e.g. PM, if the user
requested debug information about PM). SEF would then catch the message and
do nothing unless the process has registered an appropriate callback to
deal with the event. This simplifies the programming model to print debug
information, avoids duplicating code, and reduces the effort to print
debug information.
SYSTEM PROCESSES CHANGES:
- Every system process registers SEF callbacks it needs to override the default
system behavior and calls sef_startup() right after being started.
- sef_startup() does almost nothing now, but will be extended in the future to
support callbacks of its own to let RS control and synchronize with every
system process at initialization time.
- Every system process calls sef_receive() now rather than receive() directly,
to let SEF handle predefined system events.
RS CHANGES:
- RS supports a basic single-component live update protocol now, as follows:
* When an update command is issued (via "service update *"), RS notifies the
target system process to prepare for a specific update state.
* If the process doesn't respond back in time, the update is aborted.
* When the process responds back, RS kills it and marks it for refreshing.
* The process is then automatically restarted as for a buggy process and can
start running again.
* Live update is currently prototyped as a controlled failure.
that some hardware had
- clear DMA_ST_INT after DMA - fixes infinite number of interrupts
that some hardware had
- initial ATAPI DMA implementation, doesn't actually increase performance
on my test hardware so possibly not right yet, disabled by default
remembering the origin and cursor position as that feature didn't
really work properly anyway
- tty: map in video and font memory using a vm call, access it from C,
thereby eliminating pesky weird segment calls and assembly to access it,
and unbreaks loadfont (Roman Ignatov)
- bios_wini: fix bios_wini by allocating a <1MB buffers for it
- memory: preallocate ramdisk, makes it a bit faster (and doesn't
fail halfway if you allocate a huge one)
- floppy: use <1MB buffer
- ramdisk proto: because of the 2x1 page reservations, binaries
got a little fatter and didn't fit on the ramdisk any more.
increase it.
. memory maps in physical memory (for /dev/mem) with new vm interface
. pci complete_bars() seems to be buggy behaviour sometimes
. startup script opens its own stdout, stderr and stdin so init doesn't
have to do it
. pci_reserve() returns an error on devices that have already been reserved,
instead of panic()ing; the pci_reserve() library call still panics,
pci_reserve_ok() returns an int.
. this allows at_wini to use the instance value as intended, as all devices
are seen, even reserved ones
. only devices actually used by at_wini are pci_reserve()d
. pci doesn't release devices based on argv[0], as at_wini both have the
same name and multiple instances won't work together properly
libdriver. at_wini now queues messages it can't handle it receives when
waiting for an interrupt. this way it can do receive(ANY) and timeouts
should be working again (were broken for VFS, as with the advent of VFS,
at_wini could get requests from a filesystem while it was waiting for an
interrupt - as a hack, the receive() was changed to receive(HARDWARE)).
Added mq.c to libdriver, and made libdriver an actual library that
drivers link with -L../libdriver -ldriver. (So adding files, if
necessary, is easier next time.)
pm: fixed rebooting by making a copy of the monitor code from the user
process. this is necessary because that process is dead by the time
sys_abort() is called.
also added more info to the "can't reply" panic.
boot monitor.
Added SCSI_SENSE command that asks the drive, with request sense, about
diagnostics for the previous error. This command is called and the results
printed when atapi_debug is enabled and atapi errors occur.
Debug output also prints actual commands sent to the drive.
Suddenly, Andy's problem has vanished. Don't know why, minor changes
(e.g. moving the atapi packet data from stack to static) shouldn't have
fixed this.. But with the debug info, we stand a better chance of
finding out what it was if it occurs again.
. added OPENCT ioctl to at driver, which returns the number of times
a device is opened. if it's not opened exactly once, new partition info
will not be read in (at the next open after this close). included
this check in autopart.
enforced. If a call is denied, this will be kprinted. Please report any such
errors, so that I can adjust the mask before returning errors instead of
warnings.
Wrote CMOS driver. All CMOS code from FS has been removed. Currently the
driver only supports get time calls. Set time is left out as an exercise
for the book readers ... startup scripts were updated because the CMOS driver
is needed early on. (IS got same treatment.) Don't forget to run MAKEDEV cmos
in /dev/, otherwise the driver cannot be loaded.
to provide an index (0 .. 31) that is passed in the HARD_INT message when an
interrupt occurs. The NOTIFY_ARG field contains a bitmap with all indexes for
which an interrupt occured.
TTY: select and revive with new notify and FS call back;
kernel: removed old notify code; removed ugly prepare_shutdown timer
kputc: don't send to FS if PRINTF_PROC fails
names. All system processes can now either use panic() or report() from
libutils, or redefine their own function. Assertions are done via the standard
<assert.h> functionality.
This allowed removing the p_flagarlm timer from the kernel's process table.
Furthermore, I merged p_syncalrm and p_signalrm into p_alarm_timer to save
even more space. Note that processes can no longer have both a signal and
synchronous alarm timer outstanding as of now.
and type) are overwritten with newer flags/ arguments. The interface from
within the kernel is lock_notify(). User processes can make a system call with
notify(). NOTIFY fully replaces the old notification mechanism.
