Commit graph

568 commits

Author SHA1 Message Date
Erik van der Kouwe
8b459cfbb3 Provide information on lethal signals (stacktrace and signo) 2010-04-14 09:06:34 +00:00
Kees van Reeuwijk
fa3adedf63 Remove some duplicate declarations in headers.
Explicitly declare some functions as returning void.
2010-04-13 15:22:38 +00:00
Kees van Reeuwijk
bc314bda91 Remove the types Dev_t, _mnx_Gui, _mnx_Uid, and similar.
Use ANSI-style function declarations where necessary.
2010-04-13 10:58:41 +00:00
Tomas Hruby
9b599bac1d Quantum in fork
- This patch removes the time slice split between parent and child in
  fork.

- The time slice of the parent remains unchanged and the child does
  not have any.

- If the process has a scheduler, the scheduler must assign the
  quantum and priority of the new process and let it run.

- If the child does not inherit a scheduler, it is scheduled by the
  dummy default kernel policy. (servers, drivers, etc.)

- In theory, the scheduler can change the quantum even of the parent
  process and implement any policy for splitting the quantum as
  neither the parent nor the child are runnable.  Sending the
  out-of_quantum message on behalf of the processes may look like the
  right solution, however, the scheduler would probably handle the
  message before the whole fork protocol is finished. This way the
  scheduler has absolute control when the process should become
  runnable.
2010-04-10 15:27:38 +00:00
Tomas Hruby
512058ca98 This tiny cleanup makes the naming a variables in createpde() more clear. 2010-04-10 15:22:41 +00:00
Tomas Hruby
9fdb773cdb A simpler test whether to use kernel's default scheduling
- this is a small addition to the userspace scheduling.
  proc_kernel_scheduler() tests whether to use the default scheduling
  policy in kernel. It is true if the process' scheduler is NULL _or_
  self. Currently none of the tests was complete.
2010-04-10 15:19:25 +00:00
Tomas Hruby
485a037563 do_schedule() cleanup
- it is not neccessary to test whether the scheduler is a system
  process as the process already head permissions to make this call.

- it is better to test whether the scheduler has permission to make
  changes to this process before testing whether the values are valid.
2010-04-10 15:17:09 +00:00
Cristiano Giuffrida
48c6bb79f4 Driver refactory for live update and crash recovery.
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.
2010-04-08 13:41:35 +00:00
Tomas Hruby
25f2145956 Fixed a panic message
- exceptions cannot occur in kernel tasks as we don't have kernel
  tasks anymore
2010-04-07 12:50:43 +00:00
Kees van Reeuwijk
94a81c840a Removed unused variables, added const where possible. 2010-04-07 11:25:51 +00:00
Tomas Hruby
b464da5d73 do_nice.c
- this file is not used and should have been remove in r6557
2010-04-06 13:44:03 +00:00
Tomas Hruby
987b87e2ad Small fixes
- do_sync_ipc() is private

- fixed typo in a comment
2010-04-06 11:29:31 +00:00
Tomas Hruby
a774cc832f do_ipc() rearrangements
this patch does not add or change any functionality of do_ipc(), it
only makes things a little cleaner (hopefully).

Until now do_ipc() was responsible for handling all ipc calls. The
catch is that SENDA is fairly different which results in some ugly
code like this typecasting and variables naming which does not make
much sense for SENDA and makes the code hard to read.

result = mini_senda(caller_ptr, (asynmsg_t *)m_ptr, (size_t)src_dst_e);

As it is called directly from assembly, the new do_ipc() takes as
input values of 3 registers in reg_t variables (it used to be 4,
however, bit_map wasn't used so I removed it), does the checks common
to all ipc calls and call the appropriate handler either for
do_sync_ipc() (all except SENDA) or mini_senda() (for SENDA) while
typecasting the reg_t values correctly. As a result, handling SENDA
differences in do_sync_ipc() is no more needed. Also the code that
uses msg_size variable is improved a little bit.

arch_do_syscall() is simplified too.
2010-04-06 11:24:26 +00:00
Tomas Hruby
b0d37b81c4 RTS_SYS_LOCK and do_runctl()
- No need for RTS_SYS_LOCK as there are no tasks anymore.
2010-04-06 11:18:04 +00:00
Tomas Hruby
cdd6743e88 do_vtimer()
- removed comment which is not true anymore as we don't have any
  tasks. No need to take any special measures.
2010-04-06 11:16:14 +00:00
Arun Thomas
4ed3a0cf3a Convert kernel over to bsdmake 2010-04-01 22:22:33 +00:00
Kees van Reeuwijk
0a04f49d2b Fixed some incorrect uses of printf-like functions. 2010-04-01 14:30:36 +00:00
Kees van Reeuwijk
fc7dced1fa Fix printfs with too few or too many parms, remove unused vars, fix incorrect flag tests, other code cleanup. 2010-04-01 13:25:05 +00:00
Cristiano Giuffrida
d8b42a755d Move kernel signal SIGKNDELAY to system signal SIGSNDELAY and fix broken ptrace. 2010-03-31 08:55:12 +00:00
Kees van Reeuwijk
4865e3f4f9 More use of endpoint_t. Other code cleanup. 2010-03-30 14:07:15 +00:00
Tomas Hruby
63e2d73d1b Fixed brackets in bitmap macros 2010-03-30 08:34:33 +00:00
Ben Gras
f2b87f5fb7 don't print SYSTEM stacktrace on exceptions as it's not scheduled any more. 2010-03-29 15:32:19 +00:00
Tomas Hruby
62203ec287 NOREC_ENTER and NOREC_RETURN checks removed
- the reasons for these checks no longer exist

- these check are problematic on SMP
2010-03-29 11:43:10 +00:00
Tomas Hruby
5b52c5aa02 A reliable way for userspace to check if a msg is from kernel
- IPC_FLG_MSG_FROM_KERNEL status flag is returned to userspace if the
  receive was satisfied by s message which was sent by the kernel on
  behalf of a process. This perfectly reliale information.

- MF_SENDING_FROM_KERNEL flag added to processes to be able to set
  IPC_FLG_MSG_FROM_KERNEL when finishing receive if the receiver
  wasn't ready to receive immediately.

- PM is changed to use this information to confirm that the scheduling
  messages are indeed from the kernel and not faked by a process.

  PM uses sef_receive_status()

- get_work() is removed from PM to make the changes simpler
2010-03-29 11:25:01 +00:00
Tomas Hruby
2521cc6bdf Slightly faster IPC
- there are cycles wasted in the IPC call due to a fairly compliacted
  way of copying messages from userland to kernel. Sometimes this
  complicated way (generic though) is used even for copying within the
  kernel address space, sometimes it is used for copying in case _no_
  copying is necessary. The goal of this patch is to improve this a
  little bit.

- the places where a copy is from user to kernel use the
  copy_msg_from_user() kernel-kernel copies are turned into
  assignments and BuildNotifyMessage uses the delivery buffers to
  avoid copying.

- copy_msg_from_user() was introduced when removing the system task
  and is about 2/3 faster then using the current mechanism
  (phys_copy). It also avoids the PHYS_COPY_CATCH macro. Assignment is
  also faster and no copy is the fastest ;-) so perhaps there will be
  some hardly noticable performance gain besides the clean up.
2010-03-29 11:16:37 +00:00
Tomas Hruby
b4cf88a04f Userspace scheduling
- cotributed by Bjorn Swift

- In this first phase, scheduling is moved from the kernel to the PM
  server. The next steps are to a) moving scheduling to its own server
  and b) include useful information in the "out of quantum" message,
  so that the scheduler can make use of this information.

- The kernel process table now keeps record of who is responsible for
  scheduling each process (p_scheduler). When this pointer is NULL,
  the process will be scheduled by the kernel. If such a process runs
  out of quantum, the kernel will simply renew its quantum an requeue
  it.

- When PM loads, it will take over scheduling of all running
  processes, except system processes, using sys_schedctl().
  Essentially, this only results in taking over init. As children
  inherit a scheduler from their parent, user space programs forked by
  init will inherit PM (for now) as their scheduler.

 - Once a process has been assigned a scheduler, and runs out of
   quantum, its RTS_NO_QUANTUM flag will be set and the process
   dequeued. The kernel will send a message to the scheduler, on the
   process' behalf, informing the scheduler that it has run out of
   quantum. The scheduler can take what ever action it pleases, based
   on its policy, and then reschedule the process using the
   sys_schedule() system call.

- Balance queues does not work as before. While the old in-kernel
  function used to renew the quantum of processes in the highest
  priority run queue, the user-space implementation only acts on
  processes that have been bumped down to a lower priority queue.
  This approach reacts slower to changes than the old one, but saves
  us sending a sys_schedule message for each process every time we
  balance the queues. Currently, when processes are moved up a
  priority queue, their quantum is also renewed, but this can be
  fiddled with.

- do_nice has been removed from kernel. PM answers to get- and
  setpriority calls, updates it's own nice variable as well as the
  max_run_queue. This will be refactored once scheduling is moved to a
  separate server. We will probably have PM update it's local nice
  value and then send a message to whoever is scheduling the process.

- changes to fix an issue in do_fork() where processes could run out
  of quantum but bypassing the code path that handles it correctly.
  The future plan is to remove the policy from do_fork() and implement
  it in userspace too.
2010-03-29 11:07:20 +00:00
Tomas Hruby
a3ffc0f7ad Removed NIL_SYS_PROC and NIL_PROC
- NIL_PROC replaced by simple NULLs
2010-03-28 09:54:32 +00:00
Kees van Reeuwijk
98493805fd Lots of const correctness. 2010-03-27 14:31:00 +00:00
Cristiano Giuffrida
9192dbecc9 Preserve the order of IPC messages between two parties.
Currently a sequence of messages between a sender A and a receiver B of the
form: A.asynsend(M1, B); A.send(M2, B) may result in the receiver receiving
M1 first and then M2 or viceversa. This patch makes sure that the original
order M1, M2 is always preserved.

Note that the order of a hypotetical sequence A.asynsend(M1, B);
A.asynsend(M2, B) is already guaranteed by the implementation of
asynsend by design. Other senda-based wrappers can define their own
semantics.
2010-03-27 00:09:22 +00:00
Tomas Hruby
8e5a82fd49 Comment in proc.h
- This comment is not correct as the pproc_addr array does not exist.
2010-03-26 13:19:04 +00:00
Tomas Hruby
1dd6f5573a Direction flag
- ack assumes that the direction flag in eflags is clear when
  assigning two structures. It is implemented by a call to a built-in
  function which is like memcpy but needs the flag to be clear
  otherwise rubish is copied. This patch fixes the kernel entries.
2010-03-26 12:29:52 +00:00
Tomas Hruby
8451a86f0a Interrupts hadling while idle
- When the cpu halts, the interrupts are enable so the cpu may be
  woken up. When the interrupt handler returns but another interrupt
  is available it is also serviced immediately. This is not a problem
  per-se. It only slightly breaks time accounting as idle accounted is
  for the kernel time in the interrupt handler.
  
  
-  As the big kernel lock is lock/unlocked in the smp branch in the
   time acounting functions as they are called exactly at the places
   we need to take the lock) this leads to a deadlock.

- we make sure that once the interrupt handler returns from the nested
  trap, the interrupts are disabled. This means that only one
  interrupt is serviced after idle is interrupted.

- this requires the loop in apic timer calibration to keep reenabling
  the interrupts. I admit it is a little bit hackish (one line),
  however, this code is a stupid corner case at the boot time.
  Hopefully it does not matter too much.
2010-03-23 13:35:01 +00:00
Cristiano Giuffrida
bde2109b7c IPC status code for receive().
IPC changes:
- receive() is changed to take an additional parameter, which is a pointer to
a status code.
- The status code is filled in by the kernel to provide additional information
to the caller. For now, the kernel only fills in the IPC call used by the
sender.

Syslib changes:
- sef_receive() has been split into sef_receive() (with the original semantics)
and sef_receive_status() which exposes the status code to userland.
- Ideally, every sys process should gradually switch to sef_receive_status()
and use is_ipc_notify() as a dependable way to check for notify.
- SEF has been modified to use is_ipc_notify() and demonstrate how to use the
new status code.
2010-03-23 00:09:11 +00:00
Cristiano Giuffrida
45db6482e8 Prioritized NOTIFY messages for reliable asynchonrous delivery of system events. 2010-03-22 23:44:55 +00:00
Kees van Reeuwijk
c33102ea6b Miscellaneous code cleanup. 2010-03-22 20:43:06 +00:00
Ben Gras
4b2310a7ee only print 1 every 1000 spurious interrupts (per interrupt). 2010-03-22 13:55:51 +00:00
Tomas Hruby
12ef495cac atomicity fix when enabling paging
- before enabling paging VM asks kernel to resize its segments. This
  may cause kernel to segfault if APIC is used and an interrupt
  happens between this and paging enabled. As these are 2 separate
  vmctl calls it is not atomic. This patch fixes this problem. VM does
  not ask kernel to resize the segments in a separate call anymore.
  The new segments limit is part of the "enable paging" call. It
  generalizes this call in such a way that more information can be
  passed as need be or the information may be completely different if
  another architecture requires this.
2010-03-22 07:42:52 +00:00
Tomas Hruby
a5094f7d7f Kernel dumps its registers when exception
- if an exception occurs in kernel and this exception is not handled
  in an sane way and the kernel crashes, it also dumps what was loaded
  in the general purpose registers exactly at the time of the
  exception to help to debug the problem
2010-03-20 14:59:18 +00:00
Erik van der Kouwe
b42c66ed10 this patch adds access to the debug breakpoints to
the kernel. They are not used atm, but having them in trunk allows them
to be easily used when needed. To set a breakpoint that triggers when
the variable foo is written to (the most common use case), one calls:

breakpoint_set(vir2phys((vir_bytes) &foo), 0,
  BREAKPOINT_FLAG_MODE_GLOBAL |
  BREAKPOINT_FLAG_RW_WRITE |
  BREAKPOINT_FLAG_LEN_4);

It can later be disabled using:

breakpoint_set(vir2phys((vir_bytes) &foo), 0,
  BREAKPOINT_FLAG_MODE_OFF);

There are some limitations:

- There are at most four breakpoints (hardware limit); the index of the
  breakpoint (0-3) is specified as the second parameter of
  breakpoint_set.

- The breakpoint exception in the kernel is not handled and causes a
  panic; it would be reasonably easy to change this by inspecing DR6,
  printing a message, disabling the breakpoint and continuing. However,
  in my experience even just a panic can be very useful.

- Breakpoints can be set only in the part of the address space that is
  in every page table. It is useful for the kernel, but to use this for
  user processes would require saving and restoring the debug registers
  as part of the context switch. Although the CPU provides support for
  local breakpoints (I implemened this as BREAKPOINT_FLAG_LOCAL) they
  only work if task switching is used.
2010-03-19 19:15:20 +00:00
Erik van der Kouwe
19ff96081c Specify missing return type 2010-03-19 19:07:00 +00:00
Tomas Hruby
a0602c06a3 Fixed kernel stack comment 2010-03-18 16:18:22 +00:00
Ben Gras
f250bfaa13 change messy CREATEPDE macro to clean little function.
forget about the dirtypde bitmap and WIPEPDE/DONEPDE macros too.

check if mapping happens to already be in place, and if so, don't
reload cr3 (on the account of that mapping, that is).

don't reload cr3 unconditionally.
2010-03-18 13:35:41 +00:00
Erik van der Kouwe
c3e73f0793 Provide a warning is a kernel call has been denied, to ease system.conf debugging 2010-03-17 18:23:51 +00:00
Cristiano Giuffrida
cb176df60f New RS and new signal handling for system processes.
UPDATING INFO:
20100317:
        /usr/src/etc/system.conf updated to ignore default kernel calls: copy
        it (or merge it) to /etc/system.conf.
        The hello driver (/dev/hello) added to the distribution:
        # cd /usr/src/commands/scripts && make clean install
        # cd /dev && MAKEDEV hello

KERNEL CHANGES:
- Generic signal handling support. The kernel no longer assumes PM as a signal
manager for every process. The signal manager of a given process can now be
specified in its privilege slot. When a signal has to be delivered, the kernel
performs the lookup and forwards the signal to the appropriate signal manager.
PM is the default signal manager for user processes, RS is the default signal
manager for system processes. To enable ptrace()ing for system processes, it
is sufficient to change the default signal manager to PM. This will temporarily
disable crash recovery, though.
- sys_exit() is now split into sys_exit() (i.e. exit() for system processes,
which generates a self-termination signal), and sys_clear() (i.e. used by PM
to ask the kernel to clear a process slot when a process exits).
- Added a new kernel call (i.e. sys_update()) to swap two process slots and
implement live update.

PM CHANGES:
- Posix signal handling is no longer allowed for system processes. System
signals are split into two fixed categories: termination and non-termination
signals. When a non-termination signaled is processed, PM transforms the signal
into an IPC message and delivers the message to the system process. When a
termination signal is processed, PM terminates the process.
- PM no longer assumes itself as the signal manager for system processes. It now
makes sure that every system signal goes through the kernel before being
actually processes. The kernel will then dispatch the signal to the appropriate
signal manager which may or may not be PM.

SYSLIB CHANGES:
- Simplified SEF init and LU callbacks.
- Added additional predefined SEF callbacks to debug crash recovery and
live update.
- Fixed a temporary ack in the SEF init protocol. SEF init reply is now
completely synchronous.
- Added SEF signal event type to provide a uniform interface for system
processes to deal with signals. A sef_cb_signal_handler() callback is
available for system processes to handle every received signal. A
sef_cb_signal_manager() callback is used by signal managers to process
system signals on behalf of the kernel.
- Fixed a few bugs with memory mapping and DS.

VM CHANGES:
- Page faults and memory requests coming from the kernel are now implemented
using signals.
- Added a new VM call to swap two process slots and implement live update.
- The call is used by RS at update time and in turn invokes the kernel call
sys_update().

RS CHANGES:
- RS has been reworked with a better functional decomposition.
- Better kernel call masks. com.h now defines the set of very basic kernel calls
every system service is allowed to use. This makes system.conf simpler and
easier to maintain. In addition, this guarantees a higher level of isolation
for system libraries that use one or more kernel calls internally (e.g. printf).
- RS is the default signal manager for system processes. By default, RS
intercepts every signal delivered to every system process. This makes crash
recovery possible before bringing PM and friends in the loop.
- RS now supports fast rollback when something goes wrong while initializing
the new version during a live update.
- Live update is now implemented by keeping the two versions side-by-side and
swapping the process slots when the old version is ready to update.
- Crash recovery is now implemented by keeping the two versions side-by-side
and cleaning up the old version only when the recovery process is complete.

DS CHANGES:
- Fixed a bug when the process doing ds_publish() or ds_delete() is not known
by DS.
- Fixed the completely broken support for strings. String publishing is now
implemented in the system library and simply wraps publishing of memory ranges.
Ideally, we should adopt a similar approach for other data types as well.
- Test suite fixed.

DRIVER CHANGES:
- The hello driver has been added to the Minix distribution to demonstrate basic
live update and crash recovery functionalities.
- Other drivers have been adapted to conform the new SEF interface.
2010-03-17 01:15:29 +00:00
Cristiano Giuffrida
83d1f45578 Fixed a bug in interrupt handling code when removing a handler in case of
a shared IRQ.
2010-03-16 10:20:36 +00:00
Thomas Veerman
bef0e3eb63 - Add support for the ucontext system calls (getcontext, setcontext,
swapcontext, and makecontext).
- Fix VM to not erroneously think the stack segment and data segment have
  collided when a user-space thread invokes brk().
- Add test51 to test ucontext functionality.
- Add man pages for ucontext system calls.
2010-03-12 15:58:41 +00:00
Ben Gras
0937d6c367 re-establish kernel assert()s.
use the regular <assert.h> assert() instead of vmassert() in
kernel. throw out some #if 0 code. fix a few assert() conditions.
enable by default.
2010-03-10 13:00:05 +00:00
Arun Thomas
1f9ce647cf Move archtypes.h, fpu.h, and stackframe.h
Move archtypes.h to include/ dir, since several servers require it. Move
fpu.h and stackframe.h to arch-specific header directory. Make source
files and makefiles aware of the new header locations.
2010-03-09 09:41:14 +00:00
Arun Thomas
2a8fabf4ad Include directory reorg and makefile updates.
-Convert the include directory over to using bsdmake
 syntax
-Update/add mkfiles
-Modify install(1) so that it can create symlinks
-Update makefiles to use new install(1) options
-Rename /usr/include/ibm to /usr/include/i386
-Create /usr/include/machine symlink to arch header files
-Move vm_i386.h to its new home in the /usr/include/i386
-Update source files to #include the header files at their
 new homes.
-Add new gnu-includes target for building GCC headers
2010-03-08 11:04:59 +00:00
Tomas Hruby
ecf1a36d48 Fix for FPU broken by r6131
- cycles accounting must be called earlier, firstly not to clobber the %ebx
  register, secondly to be correctly called in both branches.
2010-03-05 22:23:03 +00:00
Ben Gras
35a108b911 panic() cleanup.
this change
   - makes panic() variadic, doing full printf() formatting -
     no more NO_NUM, and no more separate printf() statements
     needed to print extra info (or something in hex) before panicing
   - unifies panic() - same panic() name and usage for everyone -
     vm, kernel and rest have different names/syntax currently
     in order to implement their own luxuries, but no longer
   - throws out the 1st argument, to make source less noisy.
     the panic() in syslib retrieves the server name from the kernel
     so it should be clear enough who is panicing; e.g.
         panic("sigaction failed: %d", errno);
     looks like:
         at_wini(73130): panic: sigaction failed: 0
         syslib:panic.c: stacktrace: 0x74dc 0x2025 0x100a
   - throws out report() - printf() is more convenient and powerful
   - harmonizes/fixes the use of panic() - there were a few places
     that used printf-style formatting (didn't work) and newlines
     (messes up the formatting) in panic()
   - throws out a few per-server panic() functions
   - cleans up a tie-in of tty with panic()

merging printf() and panic() statements to be done incrementally.
2010-03-05 15:05:11 +00:00
Ben Gras
e6cb76a2e2 no more kprintf - kernel uses libsys printf now, only kputc is special
to the kernel.
2010-03-03 15:45:01 +00:00
Ben Gras
18924ea563 New P_BLOCKEDON for kernel - a macro that encodes the "who is this
process waiting for" logic, which is duplicated a few times in the
kernel. (For a new feature for top.)

Introducing it and throwing out ESRCDIED and EDSTDIED (replaced by
EDEADSRCDST - so we don't have to care which part of the blocking is
failing in system.c) simplifies some code in the kernel and callers that
check for E{DEADSRCDST,ESRCDIED,EDSTDIED}, but don't care about the
difference, a fair bit, and more significantly doesn't duplicate the
'blocked-on' logic.
2010-03-03 15:32:26 +00:00
Arun Thomas
cbd276e4ce Convert library asm files to GAS syntax 2010-03-03 14:27:30 +00:00
Kees van Reeuwijk
bf7397b64e More correctly use cp_grant_id_t.
More correctly use vir_bytes.
More correctly use endpoint_t.
2010-03-02 23:12:13 +00:00
Kees van Reeuwijk
1ba0936619 Fix some uses of uninitialized variables. 2010-02-19 10:41:02 +00:00
Kees van Reeuwijk
97c169b93a Remove some unused #include.
Remove some unused variables and computations on them.
2010-02-17 20:24:42 +00:00
Arun Thomas
b706112487 Incorporate bsdmake into buildsystem and reorganize libs 2010-02-16 14:41:33 +00:00
David van Moolenbroek
e306663455 fix the somehow newly introduced warnings 2010-02-14 18:39:47 +00:00
Erik van der Kouwe
ff835e0e35 use the verbose=2 boot monitor setting to get extensive output for debugging 2010-02-13 22:11:16 +00:00
Kees van Reeuwijk
df60646f98 Undo the use of #include <...> because it caused some errors. 2010-02-12 14:43:18 +00:00
Tomas Hruby
1b56fdb33c Time accounting based on TSC
- as thre are still KERNEL and IDLE entries, time accounting for
  kernel and idle time works the same as for any other process

- everytime we stop accounting for the currently running process,
  kernel or idle, we read the TSC counter and increment the p_cycles
  entry.

- the process cycles inherently include some of the kernel cycles as
  we can stop accounting for the process only after we save its
  context and we start accounting just before we restore its context

- this assumes that the system does not scale the CPU frequency which
  will be true for ... long time ;-)
2010-02-10 15:36:54 +00:00
Tomas Hruby
c9da61022b intr_disabled() tests removed
- we don't need to test this in kernel as we always have interrupts
  disabled

- if interrupts are enabled in kernel, it is only at very carefully
  chosen places. There are no such places now.
2010-02-09 15:29:58 +00:00
Tomas Hruby
c6fec6866f No locking in kernel code
- No locking in RTS_(UN)SET macros

- No lock_notify()

- Removed unused lock_send()

- No lock/unlock macros anymore
2010-02-09 15:26:58 +00:00
Tomas Hruby
391fd926ff TASK_PRIVILEGE and level0() removed
- there are no tasks running, we don't need TASK_PRIVILEGE priviledge anymore

- as there is no ring 1 anymore, there is no need for level0() to call sensitive
  code from ring 1 in ring 0

- 286 related macros removed as clean up
2010-02-09 15:23:31 +00:00
Tomas Hruby
ebba20a65d No CLOCK task
- no kernel tasks are runnable

- clock initialization moved to the end of main()

- the rest of the body of clock_task() is moved to bsp_timer_int_handler() as
  for now we are going to handle this on the bootstrap cpu. A change later is
  possible.
2010-02-09 15:22:43 +00:00
Tomas Hruby
728f0f0c49 Removal of the system task
* Userspace change to use the new kernel calls

	- _taskcall(SYSTASK...) changed to _kernel_call(...)

	- int 32 reused for the kernel calls

	- _do_kernel_call() to make the trap to kernel

	- kernel_call() to make the actuall kernel call from C using
	  _do_kernel_call()

	- unlike ipc call the kernel call always succeeds as kernel is
	  always available, however, kernel may return an error

* Kernel side implementation of kernel calls

	- the SYSTEm task does not run, only the proc table entry is
	  preserved

	- every data_copy(SYSTEM is no data_copy(KERNEL

	- "locking" is an empty operation now as everything runs in
	  kernel

	- sys_task() is replaced by kernel_call() which copies the
	  message into kernel, dispatches the call to its handler and
	  finishes by either copying the results back to userspace (if
	  need be) or by suspending the process because of VM

	- suspended processes are later made runnable once the memory
	  issue is resolved, picked up by the scheduler and only at
	  this time the call is resumed (in fact restarted) which does
	  not need to copy the message from userspace as the message
	  is already saved in the process structure.

	- no ned for the vmrestart queue, the scheduler will restart
	  the system calls

	- no special case in do_vmctl(), all requests remove the
	  RTS_VMREQUEST flag
2010-02-09 15:20:09 +00:00
Tomas Hruby
5e57818431 copy_msg_from_user() and copy_msg_to_user()
- copies a mesage from/to userspace without need of translating
  addresses

- the assumption is that the address space is installed, i.e. ldt and
  cr3 are loaded correctly

- if a pagefault or a general protection occurs while copying from
  userland to kernel (or vice versa) and error is returned which gives
  the caller a chance to respond in a proper way

- error happens _only_ because of a wrong user pointer if the function
  is used correctly

- if the prerequisites of the function do no hold, the function will
  most likely fail as the user address becomes random
2010-02-09 15:15:45 +00:00
Tomas Hruby
ad9ba944d1 Early address space switch
- switch_address_space() implements a switch of the user address space
  for the destination process

- this makes memory of this process easily accessible, e.g. a pointer
  valid in the userspace can be used with a little complexity to
  access the process's memory

- the switch does not happed only just before we return to userspace,
  however, it happens right after we know which process we are going
  to schedule. This happens before we start processing the misc flags
  of this process so its memory is available

- if the process becomes not runnable while processing the mics flags
  we pick a new process and we switch the address space again which
  introduces possibly a little bit more overhead, however, it is
  hopefully hidden by reducing the overheads when we actually access
  the memory
2010-02-09 15:13:52 +00:00
Tomas Hruby
b14a86ca5c Sys calls are called ipc calls now
- the syscalls are pretty much just ipc calls, however, sendrec() is
  used to implement system task (sys) calls

- sendrec() won't be used anymore for this, therefore ipc calls will
  become pure ipc calls
2010-02-09 15:13:07 +00:00
Tomas Hruby
8a03d497b8 System task initialization moved to main()
- the system task initialization code does not really need to be part
  of the system task process. An earlier initialization in kernel is
  cleaner as it does not only initialize the syscalls but also irq
  hooks etc.
2010-02-09 15:12:20 +00:00
David van Moolenbroek
f029b0e0b1 Kernel: fix sys_irqctl(IRQ_RMPOLICY) 2010-02-09 08:07:47 +00:00
Tomas Hruby
8f82633fa2 Removed useless global variable sys_call_code
- we have to same information in the message (m_ptr) where needed
2010-02-03 18:17:01 +00:00
Tomas Hruby
cca24d06d8 This patch removes the global variables who_p and who_e from the
kernel (sys task).  The main reason is that these would have to become
cpu local variables on SMP.  Once the system task is not a task but a
genuine part of the kernel there is even less reason to have these
extra variables as proc_ptr will already contain all neccessary
information. In addition converting who_e to the process pointer and
back again all the time will be avoided.

Although proc_ptr will contain all important information, accessing it
as a cpu local variable will be fairly expensive, hence the value
would be assigned to some on stack local variable. Therefore it is
better to add the 'caller' argument to the syscall handlers to pass
the value on stack anyway. It also clearly denotes on who's behalf is
the syscall being executed.

This patch also ANSIfies the syscall function headers.

Last but not least, it also fixes a potential bug in virtual_copy_f()
in case the check is disabled. So far the function in case of a
failure could possible reuse an old who_p in case this function had
not been called from the system task.

virtual_copy_f() takes the caller as a parameter too. In case the
checking is disabled, the caller must be NULL and non NULL if it is
enabled as we must be able to suspend the caller.
2010-02-03 09:04:48 +00:00
Kees van Reeuwijk
477b616fe8 Fixed a number of complaints about missing return statements.
Some cases were fixed by declaring the function void, others were fixed
by adding a return <value> statement, thereby avoiding potentially
incorrect behavior (usually in error handling).
Some enum correctness in boot.c.
2010-01-28 13:17:07 +00:00
Ben Gras
75a3d4ebde bump version number to 3.1.6, copyright year to 2010. 2010-01-27 16:19:50 +00:00
Tomas Hruby
e0f7043e04 No need to use memcpy to copy a message of 36 bytes. The overhead just
to call memcpy is half of the inline copy (using gcc -O)
2010-01-27 09:34:47 +00:00
Kees van Reeuwijk
c8a11b5453 Fixed some type inconsistencies in the kernel. 2010-01-26 12:26:06 +00:00
Kees van Reeuwijk
b67f788eea Removed a number of useless #includes 2010-01-26 10:59:01 +00:00
Kees van Reeuwijk
a701e290f7 Removed unused symbols.
Made some functions PRIVATE, including ones that aren't used anywhere.
2010-01-25 18:13:48 +00:00
Kees van Reeuwijk
a7cee5bec4 Removed unused symbols.
Minor cleanups.
2010-01-22 22:01:08 +00:00
Tomas Hruby
0cfbe936ce Removed bunch of unused variables in kernel/proc.c 2010-01-22 16:14:57 +00:00
Kees van Reeuwijk
f30c82b430 Restored idt_reload() prototype. 2010-01-21 11:40:22 +00:00
Kees van Reeuwijk
d6383bef47 Removed some unused tests. 2010-01-20 17:55:14 +00:00
David van Moolenbroek
53a6e039de remove SYS_MAPDMA 2010-01-19 21:24:42 +00:00
David van Moolenbroek
f175410902 rename message.m5_c[12] to m5_s[12] 2010-01-19 21:19:59 +00:00
Tomas Hruby
7d51b0cce1 Fixed warnings in watchdog.c 2010-01-19 14:47:25 +00:00
Tomas Hruby
5efa92f754 NMI watchdog is an awesome feature for debugging locked up kernels.
There is not that much use for it on a single CPU, however, deadlock
between kernel and system task can be delected. Or a runaway loop.

If a kernel gets locked up the timer interrupts don't occure (as all
interrupts are disabled in kernel mode). The only chance is to
interrupt the kernel by a non-maskable interrupt.

This patch generates NMIs using performance counters. It uses the most
widely available performace counters. As the performance counters are 
highly model-specific this patch is not guaranteed to work on every
machine.  Unfortunately this is also true for KVM :-/ On the other
hand adding this feature for other models is not extremely difficult
and the framework makes it hopefully easy enough.

Depending on the frequency of the CPU an NMI is generated at most
about every 0.5s If the cpu's speed is less then 2Ghz it is generated
at most every 1s. In general an NMI is generated much less often as
the performance counter counts down only if the cpu is not idle.
Therefore the overhead of this feature is fairly minimal even if the
load is high.

Uppon detecting that the kernel is locked up the kernel dumps the 
state of the kernel registers and panics.

Local APIC must be enabled for the watchdog to work.

The code is _always_ compiled in, however, it is only enabled if  
watchdog=<non-zero> is set in the boot monitor.

One corner case is serial console debugging. As dumping a lot of stuff
to the serial link may take a lot of time, the watchdog does not 
detect lockups during this time!!! as it would result in too many
false positives. 10 nmi have to be handled before the lockup is
detected. This means something between ~5s to 10s.

Another corner case is that the watchdog is enabled only after the
paging is enabled as it would be pure madness to try to get it right.
2010-01-16 20:53:55 +00:00
Cristiano Giuffrida
c5b309ff07 Merge of Wu's GSOC 09 branch (src.20090525.r4372.wu)
Main changes:
- COW optimization for safecopy.
- safemap, a grant-based interface for sharing memory regions between processes.
- Integration with safemap and complete rework of DS, supporting new data types
  natively (labels, memory ranges, memory mapped ranges).
- For further information:
  http://wiki.minix3.org/en/SummerOfCode2009/MemoryGrants

Additional changes not included in the original Wu's branch:
- Fixed unhandled case in VM when using COW optimization for safecopy in case
  of a block that has already been shared as SMAP.
- Better interface and naming scheme for sys_saferevmap and ds_retrieve_map
  calls.
- Better input checking in syslib: check for page alignment when creating
  memory mapping grants.
- DS notifies subscribers when an entry is deleted.
- Documented the behavior of indirect grants in case of memory mapping.
- Test suite in /usr/src/test/safeperf|safecopy|safemap|ds/* reworked
  and extended.
- Minor fixes and general cleanup.
- TO-DO: Grant ids should be generated and managed the way endpoints are to make
sure grant slots are never misreused.
2010-01-14 15:24:16 +00:00
Kees van Reeuwijk
da3b64d8bc Fixed a bug in do_sdevio() that broke I/O size computations.
Removed redundant size computations.
Cleaned up code.
2010-01-14 14:51:23 +00:00
Kees van Reeuwijk
9d247900c0 Remove obsolete m_ptr calculations in try_one() and mini_senda(). 2010-01-14 12:04:24 +00:00
Tomas Hruby
98563a4afa Killing Minix by typing Q on serial console
- if debugging on serial console is enabled typing Q kills the system. It is
  handy if the system gets locked up and the timer interrupts still work. Good
  for remote debugging.

- NOT_REACHABLE reintroduced and fixed. It should be used for marking code which
  is not reachable because the previous code _should_ not return. Such places
  are not always obvious
2010-01-14 09:46:16 +00:00
Tomas Hruby
8a2a4f97fc Fixed redundant typecast in lapic write/read macros 2010-01-13 18:23:58 +00:00
Tomas Hruby
42c13951a7 APIC disabled if CPU lacks TSC
- we cannot calibrate local APIC timer in such a case

- fixes possible uninitialized variable problem during calibration if no TSC
2010-01-13 18:22:41 +00:00
Kees van Reeuwijk
ad4c0ff698 Fixed a bug in apic.c that broke lapic_stop_timer().
Fixed bugs in liveupdate.c that rendered load_state_info() meaningless.
More informative error message in do_config() in service.c.
2010-01-13 14:44:19 +00:00
Tomas Hruby
a316221fbf Local apic is dissabled by default
to enable it set no_apic=0 in the boot monitor
2010-01-11 17:21:19 +00:00
Cristiano Giuffrida
d1fd04e72a Initialization protocol for system services.
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.
2010-01-08 01:20:42 +00:00
Erik van der Kouwe
38ed5b2685 Fix brackets in kernel/arch/i386/include/archconst.h 2010-01-06 08:46:33 +00:00
Kees van Reeuwijk
d8f3af3672 Fixed a typing bug.
More explicit type conversion from virual to physical bytes.
Bracket negative #defines for extra paranoia.
Added a forgotten 'void' to a function.
2010-01-06 08:23:14 +00:00
David van Moolenbroek
ac9ab099c8 General cleanup:
- clean up kernel section of minix/com.h somewhat
- remove ALLOCMEM and VM_ALLOCMEM calls
- remove non-safecopy and minix-vmd support from Inet
- remove SYS_VIRVCOPY and SYS_PHYSVCOPY calls
- remove obsolete segment encoding in SYS_SAFECOPY*
- remove DEVCTL call, svrctl(FSDEVUNMAP), map_driverX
- remove declarations of unimplemented svrctl requests
- remove everything related to swapping to disk
- remove floppysetup.sh
- remove traces of rescue device
- update DESCRIBE.sh with new devices
- some other small changes
2010-01-05 19:39:27 +00:00
David van Moolenbroek
bac0e91705 typo (Bug#376, reported by Kees van Reeuwijk) 2010-01-04 12:29:51 +00:00
David van Moolenbroek
c473cfcdda more kernel header typos 2010-01-01 20:18:05 +00:00
David van Moolenbroek
44e46860c7 Kernel: fix do_stime.c header comment (2) 2009-12-30 14:56:54 +00:00
David van Moolenbroek
010e23e504 Kernel: fix do_stime.c header comment 2009-12-30 14:56:35 +00:00
David van Moolenbroek
ac9a5829a2 suppress kernel/VM memory debugging information 2009-12-29 21:35:12 +00:00
David van Moolenbroek
e423c86009 ptrace(2) modifications:
- add T_GETRANGE/T_SETRANGE to get/set ranges of values
- change EIO error code to EFAULT
- move common-I&D text-to-data translation to umap_local
2009-12-29 21:32:15 +00:00
Thomas Veerman
958b25be50 - Introduce support for sticky bit.
- Revise VFS-FS protocol and update VFS/MFS/ISOFS accordingly.
- Clean up MFS by removing old, dead code (backwards compatibility is broken by
  the new VFS-FS protocol, anyway) and rewrite other parts. Also, make sure all
  functions have proper banners and prototypes.
- VFS should always provide a (syntactically) valid path to the FS; no need for
  the FS to do sanity checks when leaving/entering mount points.
- Fix several bugs in MFS:
  - Several path lookup bugs in MFS.
  - A link can be too big for the path buffer.
  - A mountpoint can become inaccessible when the creation of a new inode
    fails, because the inode already exists and is a mountpoint.
- Introduce support for supplemental groups.
- Add test 46 to test supplemental group functionality (and removed obsolete
  suppl. tests from test 2).
- Clean up VFS (not everything is done yet).
- ISOFS now opens device read-only. This makes the -r flag in the mount command
  unnecessary (but will still report to be mounted read-write).
- Introduce PipeFS. PipeFS is a new FS that handles all anonymous and
  named pipes. However, named pipes still reside on the (M)FS, as they are part
  of the file system on disk. To make this work VFS now has a concept of
  'mapped' inodes, which causes read, write, truncate and stat requests to be
  redirected to the mapped FS, and all other requests to the original FS.
2009-12-20 20:27:14 +00:00
Cristiano Giuffrida
b4d6d9db26 Fix bug in IPC deadlock detection code.
The old deadlock code was misplaced and unable to deal with asynchronous
IPC primitives (notify and senda) effectively. As an example, the following
sequence of messages allowed the deadlock detection code to
trigger a false positive:
1. A.notify(B)
2. A.receive(B)
3. B.receive(A)
1. B.notify(A)
The solution is to run the deadlock detection routine only when a process is
about to block in mini_send() or mini_receive().
2009-12-16 23:32:08 +00:00
Cristiano Giuffrida
f4574783dc Rewrite of boot process
KERNEL CHANGES:
- The kernel only knows about privileges of kernel tasks and the root system
process (now RS).
- Kernel tasks and the root system process are the only processes that are made
schedulable by the kernel at startup. All the other processes in the boot image
don't get their privileges set at startup and are inhibited from running by the
RTS_NO_PRIV flag.
- Removed the assumption on the ordering of processes in the boot image table.
System processes can now appear in any order in the boot image table.
- Privilege ids can now be assigned both statically or dynamically. The kernel
assigns static privilege ids to kernel tasks and the root system process. Each
id is directly derived from the process number.
- User processes now all share the static privilege id of the root user
process (now INIT).
- sys_privctl split: we have more calls now to let RS set privileges for system
processes. SYS_PRIV_ALLOW / SYS_PRIV_DISALLOW are only used to flip the
RTS_NO_PRIV flag and allow / disallow a process from running. SYS_PRIV_SET_SYS /
SYS_PRIV_SET_USER are used to set privileges for a system / user process.
- boot image table flags split: PROC_FULLVM is the only flag that has been
moved out of the privilege flags and is still maintained in the boot image
table. All the other privilege flags are out of the kernel now.

RS CHANGES:
- RS is the only user-space process who gets to run right after in-kernel
startup.
- RS uses the boot image table from the kernel and three additional boot image
info table (priv table, sys table, dev table) to complete the initialization
of the system.
- RS checks that the entries in the priv table match the entries in the boot
image table to make sure that every process in the boot image gets schedulable.
- RS only uses static privilege ids to set privileges for system services in
the boot image.
- RS includes basic memory management support to allocate the boot image buffer
dynamically during initialization. The buffer shall contain the executable
image of all the system services we would like to restart after a crash.
- First step towards decoupling between resource provisioning and resource
requirements in RS: RS must know what resources it needs to restart a process
and what resources it has currently available. This is useful to tradeoff
reliability and resource consumption. When required resources are missing, the
process cannot be restarted. In that case, in the future, a system flag will
tell RS what to do. For example, if CORE_PROC is set, RS should trigger a
system-wide panic because the system can no longer function correctly without
a core system process.

PM CHANGES:
- The process tree built at initialization time is changed to have INIT as root
with pid 0, RS child of INIT and all the system services children of RS. This
is required to make RS in control of all the system services.
- PM no longer registers labels for system services in the boot image. This is
now part of RS's initialization process.
2009-12-11 00:08:19 +00:00
Tomas Hruby
51065a1b47 Cooments to warn not to use certains instructions
- gas2ack cannot handle all variants of some instructions. Until this issues is
  addressed, this patch places a big warning where appropriate. This code is not
  supposed to change frequently.
2009-12-07 12:01:05 +00:00
David van Moolenbroek
fe982ca684 FPU: fix field names, compiler warning, long lines 2009-12-02 23:12:46 +00:00
Ben Gras
bd42705433 FPU context switching support by Evgeniy Ivanov. 2009-12-02 13:01:48 +00:00
David van Moolenbroek
fce9fd4b4e Add 'getidle' CPU utilization measurement infrastructure 2009-12-02 11:52:26 +00:00
Ben Gras
7c0cdc61bc fix for race condition - IRQ can happen between clearing the endpoint
of the handling process and before removing the hook. The handler function
will panic then.
2009-12-01 16:46:27 +00:00
David van Moolenbroek
6da61b8f05 fix _NSIG usage 2009-11-28 13:20:50 +00:00
David van Moolenbroek
709a739b52 Kernel: unbreak load averages 2009-11-28 13:16:03 +00:00
David van Moolenbroek
6c6e1db676 Kernel: fix faulty trap check 2009-11-28 13:15:07 +00:00
Tomas Hruby
8a44a44cb9 Local APIC
- local APIC timer used as the source of time

- PIC is still used as the hw interrupt controller as we don't have
  enough info without ACPI or MPS to set up IO APICs

- remapping of APIC when switching paging on, uses the new mechanism
  to tell VM what phys areas to map in kernel's virtual space

- one more step to SMP

based on code by Arun C.
2009-11-16 21:41:44 +00:00
Tomas Hruby
9e62bd5241 .align replaced by .balign in mpx386.S 2009-11-13 09:30:45 +00:00
Tomas Hruby
cb9faaebfd No need for a special idle queue
- as the idle task is never placed on any run queue, we don't need any special
  idle queue.

- one more queue available for user processes
2009-11-12 08:47:25 +00:00
Tomas Hruby
ad4dcaab71 Idle task never runs
- idle task becomes a pseudo task which is never scheduled. It is never put on
  any run queue and never enters userspace. An entry for this task still remains
  in the process table for time accounting

- Instead of panicing if there is not process to schedule, pick_proc() returns
  NULL which is a signal to put the cpu in an idle state and set everything in
  such a way that after receiving and interrupt it looks like idle task was
  preempted

- idle task is set non-preemptible to avoid handling in the timer interrupt code
  which make userspace scheduling simpler as idle task does not need to be
  handled as a special case.
2009-11-12 08:42:18 +00:00
Tomas Hruby
37a7e1b76b Use of isemptyp() macro instead of testing RTS_SLOT_FREE flag
- some code used to test if only this flag is set, some if also this flag is
  set. This change unifies the test
2009-11-12 08:35:26 +00:00
Tomas Hruby
b3b0a18403 allow kernel to tell VM extra physical addresses it wants mapped in.
used in the future for mapping in local APIC memory.
2009-11-11 12:07:06 +00:00
Tomas Hruby
9ba3b53de8 kernel/proc.h can be included in kernel assembky files
- the gnu .S are compiled with __ASSEMBLY__ macro set which allows us to
  conditionaly remove C stuff from the proc.h file when included in assembly
  files
2009-11-10 09:14:50 +00:00
Tomas Hruby
a972f4bacc All macros defining rts flags are prefixed with RTS_
- macros used with RTS_SET group of macros to define struct proc p_rts_flags are
  now prefixed with RTS_ to make things clear
2009-11-10 09:11:13 +00:00
Tomas Hruby
daf7940c69 pick_proc() called only just before returning to userspace
- new proc_is_runnable() macro to test whether process is runnable. All tests
  whether p_rts_flags == 0 converted to use this macro

- pick_proc() calls removed from enqueue() and dequeue()

- removed the test for recursive calls from pick_proc() as it certainly cannot
  be called recursively now

- PREEMPTED flag to mark processes that were preempted by enqueueuing a higher
  priority process in enqueue()

- enqueue_head() to enqueue PREEMPTED processes again at the head of their
  current priority queue

- NO_QUANTUM flag to block and dequeue processes preempted by timer tick with
  exceeded quantum. They need to be enqueued again in schedcheck()

- next_ptr global variable removed
2009-11-09 17:48:31 +00:00
Tomas Hruby
ae75f9d4e5 Removal of the executable flag from files that cannot be executed
- 755 -> 644
2009-11-09 10:26:00 +00:00
David van Moolenbroek
a07f8d7646 Fix ptrace bug when reattaching to a detached process 2009-11-09 08:12:25 +00:00
Tomas Hruby
ebbce7507b Complete ovehaul of mode switching code
- after a trap to kernel, the code automatically switches to kernel
  stack, in the future local to the CPU

- k_reenter variable replaced by a test whether the CS is kernel cs or
  not. The information is passed further if needed. Removes a global
  variable which would need to be cpu local

- no need for global variables describing the exception or trap
  context. This information is kept on stack and a pointer to this
  structure is passed to the C code as a single structure

- removed loadedcr3 variable and its use replaced by reading the %cr3
  register

- no need to redisable interrupts in restart() as they are already
  disabled.

- unified handling of traps that push and don't push errorcode

- removed save() function as the process context is not saved directly
  to process table but saved as required by the trap code. Essentially
  it means that save() code is inlined everywhere not only in the
  exception handling routine

- returning from syscall is more arch independent - it sets the retger
  in C

- top of the x86 stack contains the current CPU id and pointer to the
  currently scheduled process (the one right interrupted) so the mode
  switch code can find where to save the context without need to use
  proc_ptr which will be cpu local in the future and therefore
  difficult to access in assembler and expensive to access in general

- some more clean up of level0 code. No need to read-back the argument
  passed in
  %eax from the proc structure. The mode switch code does not clobber
  %the general registers and hence we can just call what is in %eax

- many assebly macros in sconst.h as they will be reused by the apic
  assembly
2009-11-06 09:08:26 +00:00
Tomas Hruby
f2a1f21a39 Clock task split
- preemption handled in the clock timer interrupt handler, not in the clock task

- more achitecture independent clock timer handling code

- smp ready as each CPU can have its own timer
2009-11-06 09:04:15 +00:00
Tomas Hruby
616d936638 vmassert reports also the source file in which it was triggered 2009-11-04 15:30:08 +00:00
Tomas Hruby
cf854041ce Hardware interrupts code path cleanup
- the PIC master and slave irq handlers don't pass the irq hook pointer but just
  the irq number. It gives a little bit more information to the C handler as the
  irq number is not lost

- the irq code path is more achitecture independent. i386 hw interrupts are
  called irq and whereever the code is arch independent enough hw_intr_
  functions are called to mask/unmask interrupts

- the legacy PIC is not the only possible interrupt controller in the x86 world,
  therefore the intr_(un)mask functions were renamed to signal their
  functionality explicitly. APIC will add their own.

- masking and unmasking PIC interrupt lines is removed from assembler and all
  the functionality is rewriten in C and moved to i8259.c

- interrupt handlers have to unmask the interrupt line if all irq handlers are
  done. Assembler does not do it anymore
2009-11-04 13:24:56 +00:00
Ben Gras
7e73260cf5 - enable remembering of device memory ranges set by PCI and
told to kernel
  - makes VM ask the kernel if a certain process is allowed
    to map in a range of physical memory (VM rounds it to page
    boundaries afterwards - but it's impossible to map anything
    smaller otherwise so I assume this is safe, i.e. there won't
    be anything else in that page; certainly no regular memory)
  - VM permission check cleanup (no more hardcoded calls, less
    hardcoded logic, more readable main loop), a loose end left
    by GQ
  - remove do_copy warning, as the ipc server triggers this but
    it's no more harmful than the special cases already excluded
    explicitly (VFS, PM, etc).
2009-11-03 11:12:23 +00:00
David van Moolenbroek
f814fe41be Kernel: add support for indirect grants 2009-11-02 22:30:37 +00:00
David van Moolenbroek
f89388c241 Kernel, servers: remove unused proto.h definitions 2009-10-31 14:11:50 +00:00
Tomas Hruby
403764c538 Conversion of kernel assembly from ACK to GNU
- .s files removed and replaced by .S as the .S is a standard extension for assembly that needs preprocessing
2009-10-30 16:00:44 +00:00
Ben Gras
53567bf741 no DEBUG_VMASSERT committed 2009-10-18 20:08:55 +00:00
Ben Gras
24e1e83028 really revert endpoint_t -> int
debugging info on panic: decode segment selectors and descriptors, now moved
to arch-specific part, prototypes added; sanity checking in debug.h made
optional with vmassert().
2009-10-05 15:47:23 +00:00
Ben Gras
30804b9ed7 thanks to tomas: fix for level0() race condition - global variable can
be used concurrently.  pass the function in eax instead; this gets rid
of the global variable.  also execute the function directly if we're
already trapped into the kernel.

revert of u32_t endpoint_t to int (some code assumes endpoints are
negative for negative slot numbers).
2009-10-05 15:22:31 +00:00
Ben Gras
88a12c70d2 little more info in pagefault exception handler. 2009-10-03 12:23:02 +00:00
Ben Gras
6bd3002f06 - exact magic values for entered/nonentered states in recursive enter check
- read_*() functions to read segment selector values
 - decode loaded segments on panic
2009-10-03 12:17:46 +00:00
Ben Gras
fe35879325 - panic if there's no runnable process
- more basic sanity check before recursive enter check (data segment)
 - try to jump to boot monitor instantly on recursive panic
2009-10-03 11:30:35 +00:00
David van Moolenbroek
49808dcf77 PM delay call infrastructure improvements
- allow PM to tell sys_runctl() whether to use delay call feature
- only use this feature in PM for delivering signals - not for exits
- do better error checking in PM on sys_runctl() calls
- rename SIGKREADY to SIGNDELAY
2009-10-01 10:36:09 +00:00
Tomas Hruby
6539c356c6 idle_task() declared 3x in kernel/proto.h. 2 declarations removed 2009-10-01 07:59:15 +00:00
David van Moolenbroek
b423d7b477 Merge of David's ptrace branch. Summary:
o Support for ptrace T_ATTACH/T_DETACH and T_SYSCALL
o PM signal handling logic should now work properly, even with debuggers
  being present
o Asynchronous PM/VFS protocol, full IPC support for senda(), and
  AMF_NOREPLY senda() flag

DETAILS

Process stop and delay call handling of PM:
o Added sys_runctl() kernel call with sys_stop() and sys_resume()
  aliases, for PM to stop and resume a process
o Added exception for sending/syscall-traced processes to sys_runctl(),
  and matching SIGKREADY pseudo-signal to PM
o Fixed PM signal logic to deal with requests from a process after
  stopping it (so-called "delay calls"), using the SIGKREADY facility
o Fixed various PM panics due to race conditions with delay calls versus
  VFS calls
o Removed special PRIO_STOP priority value
o Added SYS_LOCK RTS kernel flag, to stop an individual process from
  running while modifying its process structure

Signal and debugger handling in PM:
o Fixed debugger signals being dropped if a second signal arrives when
  the debugger has not retrieved the first one
o Fixed debugger signals being sent to the debugger more than once
o Fixed debugger signals unpausing process in VFS; removed PM_UNPAUSE_TR
  protocol message
o Detached debugger signals from general signal logic and from being
  blocked on VFS calls, meaning that even VFS can now be traced
o Fixed debugger being unable to receive more than one pending signal in
  one process stop
o Fixed signal delivery being delayed needlessly when multiple signals
  are pending
o Fixed wait test for tracer, which was returning for children that were
  not waited for
o Removed second parallel pending call from PM to VFS for any process
o Fixed process becoming runnable between exec() and debugger trap
o Added support for notifying the debugger before the parent when a
  debugged child exits
o Fixed debugger death causing child to remain stopped forever
o Fixed consistently incorrect use of _NSIG

Extensions to ptrace():
o Added T_ATTACH and T_DETACH ptrace request, to attach and detach a
  debugger to and from a process
o Added T_SYSCALL ptrace request, to trace system calls
o Added T_SETOPT ptrace request, to set trace options
o Added TO_TRACEFORK trace option, to attach automatically to children
  of a traced process
o Added TO_ALTEXEC trace option, to send SIGSTOP instead of SIGTRAP upon
  a successful exec() of the tracee
o Extended T_GETUSER ptrace support to allow retrieving a process's priv
  structure
o Removed T_STOP ptrace request again, as it does not help implementing
  debuggers properly
o Added MINIX3-specific ptrace test (test42)
o Added proper manual page for ptrace(2)

Asynchronous PM/VFS interface:
o Fixed asynchronous messages not being checked when receive() is called
  with an endpoint other than ANY
o Added AMF_NOREPLY senda() flag, preventing such messages from
  satisfying the receive part of a sendrec()
o Added asynsend3() that takes optional flags; asynsend() is now a
  #define passing in 0 as third parameter
o Made PM/VFS protocol asynchronous; reintroduced tell_fs()
o Made PM_BASE request/reply number range unique
o Hacked in a horrible temporary workaround into RS to deal with newly
  revealed RS-PM-VFS race condition triangle until VFS is asynchronous

System signal handling:
o Fixed shutdown logic of device drivers; removed old SIGKSTOP signal
o Removed is-superuser check from PM's do_procstat() (aka getsigset())
o Added sigset macros to allow system processes to deal with the full
  signal set, rather than just the POSIX subset

Miscellaneous PM fixes:
o Split do_getset into do_get and do_set, merging common code and making
  structure clearer
o Fixed setpriority() being able to put to sleep processes using an
  invalid parameter, or revive zombie processes
o Made find_proc() global; removed obsolete proc_from_pid()
o Cleanup here and there

Also included:
o Fixed false-positive boot order kernel warning
o Removed last traces of old NOTIFY_FROM code

THINGS OF POSSIBLE INTEREST

o It should now be possible to run PM at any priority, even lower than
  user processes
o No assumptions are made about communication speed between PM and VFS,
  although communication must be FIFO
o A debugger will now receive incoming debuggee signals at kill time
  only; the process may not yet be fully stopped
o A first step has been made towards making the SYSTEM task preemptible
2009-09-30 09:57:22 +00:00
Ben Gras
bcd7d04203 throw out FIXME reminders for release 2009-09-30 07:40:34 +00:00
Ben Gras
da67a3af00 disable 'clever' optimisation (workaround for vmware(?) problem) 2009-09-28 15:47:01 +00:00
Ben Gras
e900735ddd old reminder 2009-09-25 17:58:23 +00:00
Ben Gras
cd3e83f849 get_randomness restored. 2009-09-25 17:57:24 +00:00
Ben Gras
e64e75dbc5 also don't let user process change ss segment selector when returning from
signal.
2009-09-25 17:44:26 +00:00