Commit graph

134 commits

Author SHA1 Message Date
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
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
David van Moolenbroek
a07f8d7646 Fix ptrace bug when reattaching to a detached process 2009-11-09 08:12:25 +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
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
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
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
Ben Gras
cd8b915ed9 Primary goal for these changes is:
- no longer have kernel have its own page table that is loaded
    on every kernel entry (trap, interrupt, exception). the primary
    purpose is to reduce the number of required reloads.
Result:
  - kernel can only access memory of process that was running when
    kernel was entered
  - kernel must be mapped into every process page table, so traps to
    kernel keep working
Problem:
  - kernel must often access memory of arbitrary processes (e.g. send
    arbitrary processes messages); this can't happen directly any more;
    usually because that process' page table isn't loaded at all, sometimes
    because that memory isn't mapped in at all, sometimes because it isn't
    mapped in read-write.
So:
  - kernel must be able to map in memory of any process, in its own
    address space.
Implementation:
  - VM and kernel share a range of memory in which addresses of
    all page tables of all processes are available. This has two purposes:
      . Kernel has to know what data to copy in order to map in a range
      . Kernel has to know where to write the data in order to map it in
    That last point is because kernel has to write in the currently loaded
    page table.
  - Processes and kernel are separated through segments; kernel segments
    haven't changed.
  - The kernel keeps the process whose page table is currently loaded
    in 'ptproc.'
  - If it wants to map in a range of memory, it writes the value of the
    page directory entry for that range into the page directory entry
    in the currently loaded map. There is a slot reserved for such
    purposes. The kernel can then access this memory directly.
  - In order to do this, its segment has been increased (and the
    segments of processes start where it ends).
  - In the pagefault handler, detect if the kernel is doing
    'trappable' memory access (i.e. a pagefault isn't a fatal
     error) and if so,
       - set the saved instruction pointer to phys_copy_fault,
	 breaking out of phys_copy
       - set the saved eax register to the address of the page
	 fault, both for sanity checking and for checking in
	 which of the two ranges that phys_copy was called
	 with the fault occured
  - Some boot-time processes do not have their own page table,
    and are mapped in with the kernel, and separated with
    segments. The kernel detects this using HASPT. If such a
    process has to be scheduled, any page table will work and
    no page table switch is done.

Major changes in kernel are
  - When accessing user processes memory, kernel no longer
    explicitly checks before it does so if that memory is OK.
    It simply makes the mapping (if necessary), tries to do the
    operation, and traps the pagefault if that memory isn't present;
    if that happens, the copy function returns EFAULT.
    So all of the CHECKRANGE_OR_SUSPEND macros are gone.
  - Kernel no longer has to copy/read and parse page tables.
  - A message copying optimisation: when messages are copied, and
    the recipient isn't mapped in, they are copied into a buffer
    in the kernel. This is done in QueueMess. The next time
    the recipient is scheduled, this message is copied into
    its memory. This happens in schedcheck().
    This eliminates the mapping/copying step for messages, and makes
    it easier to deliver messages. This eliminates soft_notify.
  - Kernel no longer creates a page table at all, so the vm_setbuf
    and pagetable writing in memory.c is gone.

Minor changes in kernel are
  - ipc_stats thrown out, wasn't used
  - misc flags all renamed to MF_*
  - NOREC_* macros to enter and leave functions that should not
    be called recursively; just sanity checks really
  - code to fully decode segment selectors and descriptors
    to print on exceptions
  - lots of vmassert()s added, only executed if DEBUG_VMASSERT is 1
2009-09-21 14:31:52 +00:00
David van Moolenbroek
f2def7d360 Kernel: correct a few SYSTEM source documentation comments 2009-09-17 20:51:34 +00:00
Tomas Hruby
4fd433694f proc_addr() returns address based on location in proc array
- pproc_addr is not neccessary to get the address of a process if we know its
  number

- local proc variables in system calls implementation (sys_task) conflicts with
  the global proc array of all process, therefore the variable were renamed to
  proc_nr as they hold the process number
2009-09-15 09:57:22 +00:00
David van Moolenbroek
9c19233879 Kernel: do_[sv]devio.c header corrections 2009-09-06 15:54:15 +00:00
David van Moolenbroek
979bcfc195 - sys_privctl: don't mix message types
- sys_privctl: remove CTL_MM_PRIV (third parameter)
- remove obsolete sys_svrctl.c library file
2009-09-06 12:37:13 +00:00
David van Moolenbroek
323f0abdd6 Support for setitimer(ITIMER_VIRTUAL/ITIMER_PROF). New test (41) for setitimer. 2009-08-15 21:37:26 +00:00
David van Moolenbroek
5e173f55f5 Remove leftover PowerPC cruft. Reported by Evgeniy Ivanov. 2009-07-07 18:55:11 +00:00
David van Moolenbroek
b8b8f537bd IPC privileges fixes
Kernel:
o Remove s_ipc_sendrec, instead using s_ipc_to for all send primitives
o Centralize s_ipc_to bit manipulation,
  - disallowing assignment of bits pointing to unused priv structs;
  - preventing send-to-self by not setting bit for own priv struct;
  - preserving send mask matrix symmetry in all cases
o Add IPC send mask checks to SENDA, which were missing entirely somehow
o Slightly improve IPC stats accounting for SENDA
o Remove SYSTEM from user processes' send mask
o Half-fix the dependency between boot image order and process numbers,
  - correcting the table order of the boot processes;
  - documenting the order requirement needed for proper send masks;
  - warning at boot time if the order is violated

RS:
o Add support in /etc/drivers.conf for servers that talk to user processes,
  - disallowing IPC to user processes if no "ipc" field is present
  - adding a special "USER" label to explicitly allow IPC to user processes
o Always apply IPC masks when specified; remove -i flag from service(8)
o Use kernel send mask symmetry to delay adding IPC permissions for labels
  that do not exist yet, adding them to that label's process upon creation
o Add VM to ipc permissions list for rtl8139 and fxp in drivers.conf

Left to future fixes:
o Removal of the table order vs process numbers dependency altogether,
  possibly using per-process send list structures as used for SYSTEM calls
o Proper assignment of send masks to boot processes;
  some of the assigned (~0) masks are much wider than necessary
o Proper assignment of IPC send masks for many more servers in drivers.conf
o Removal of the debugging warning about the now legitimate case where RS's
  add_forward_ipc cannot find the IPC destination's label yet
2009-07-02 16:25:31 +00:00
David van Moolenbroek
c2aef85eda Clear trace bit for child on fork.
Without this, a forking single-stepped process will have its child
die from a TRAP signal right away.
2009-05-13 21:58:10 +00:00
Ben Gras
9647fbc94e moved type and constants for random data to include file;
added consistency check in random; added source of randomness
internal to random using timing; only retrieve random bins that are full.
2009-04-02 15:24:44 +00:00
Ben Gras
b560a36b20 trace fix contributed by Joren l'Ami 2009-04-02 11:38:23 +00:00
Ben Gras
6e86e6706d fix compiler warning; missing memory range check 2009-02-05 13:00:03 +00:00
Ben Gras
c628f24bc2 moved stacktrace to sysctl, as vmctl is very privileged so can't
be used outside VM. IS code cleanup. added stacktrace feature to IS.
2009-01-27 12:54:33 +00:00
Ben Gras
3cc092ff06 . new kernel call sysctl for generic unprivileged system operations;
now used for printing diagnostic messages through the kernel message
   buffer. this lets processes print diagnostics without sending messages
   to tty and log directly, simplifying the message protocol a lot and
   reducing difficulties with deadlocks and other situations in which
   diagnostics are blackholed (e.g. grants don't work). this makes
   DIAGNOSTICS(_S), ASYN_DIAGNOSTICS and DIAG_REPL obsolete, although tty
   and log still accept the codes for 'old' binaries. This also simplifies
   diagnostics in several servers and drivers - only tty needs its own
   kputc() now.
 . simplifications in vfs, and some effort to get the vnode references
   right (consistent) even during shutdown. m_mounted_on is now NULL
   for root filesystems (!) (the original and new root), a less awkward
   special case than 'm_mounted_on == m_root_node'. root now has exactly
   one reference, to root, if no files are open, just like all other
   filesystems. m_driver_e is unused.
2009-01-26 17:43:59 +00:00
Ben Gras
cd54beeb30 cprofile not conditional 2009-01-09 21:45:27 +00:00
Ben Gras
f0000078c3 make kernel leave a page-sized gap in its code and data to not be
mapped in if so configured.
2008-12-18 14:30:55 +00:00
Ben Gras
5db1a042c2 stacktrace feature. 2008-12-11 15:33:43 +00:00
Ben Gras
034b5c6042 PM_PROC_NR shouldn't be hardcoded as the caller. 2008-12-11 14:18:51 +00:00
Ben Gras
c4fb567bd5 . replace HZ by runtime system_hz (sysenv variable 'hz')
. new flag PROC_FULLVM in table indicating process wants full address
   space (this is then created and managed by VM)
2008-12-11 14:15:23 +00:00
Ben Gras
c078ec0331 Basic VM and other minor improvements.
Not complete, probably not fully debugged or optimized.
2008-11-19 12:26:10 +00:00
Philip Homburg
4a86b1fea5 Changes to debug output, mostly rate limiting. 2008-02-22 11:00:06 +00:00
Philip Homburg
3c2e122d6d Disabled code to set ipc_stats_target. 2008-02-22 10:58:27 +00:00
Philip Homburg
2679321ba0 Added do_mapdma. 2008-02-22 10:51:37 +00:00
Philip Homburg
fab77fd01f Added do_stime.c, return boot time in do_times.c 2007-08-07 12:20:31 +00:00
Philip Homburg
4f787035ea Removed check for grants that wrap. 2007-08-07 12:19:45 +00:00
Ben Gras
b00f287449 Restore user-owned bits from PSW after a signal handler, instead of
copying complete PSW after signal handler.

This fixes a psw corruption bug reported by Jens de Smit <jst260@few.vu.nl>.
2007-05-08 15:43:00 +00:00
Philip Homburg
c082f607df Disallow unaligned access to I/O ports. 2007-04-23 13:31:45 +00:00
Philip Homburg
d2cec7db49 Disallow unaligned access to I/O ports. 2007-04-23 13:31:16 +00:00
Philip Homburg
7541e0753b Separate permissions for sendrec. Actually initialize send/sendrec permissions
for data supplied by rs.
2007-04-23 13:30:04 +00:00
Philip Homburg
d80e25068c GET_PRIVID: return the ID of a process' privilege structure. 2007-04-23 13:28:14 +00:00
Ben Gras
7507ebfeca remove debug message 2007-03-30 15:17:03 +00:00
Ben Gras
238ae978ba Don't allow sys_kill to SELF alltogether. 2007-02-23 13:01:55 +00:00
Ben Gras
a9f2f36f46 If a process does sys_kill on SELF (such as in panic() of servers and drivers
if a PM exit fails, until they are compiled with the new panic() function that
is), don't reply to it as the endpoint has been cleared.
2007-02-23 12:55:29 +00:00
Ben Gras
3bb73b431b add/re-enable at_wini debug output 2007-02-21 17:49:35 +00:00
Ben Gras
a47531cc97 removed some verbose messages 2007-02-16 15:53:10 +00:00
Ben Gras
9f2f3dd488 don't call mkdep with an absolute path 2007-02-08 16:26:20 +00:00
Ben Gras
41e9fedf87 Mostly bugfixes of bugs triggered by the test set.
bugfixes:
 SYSTEM:
 . removed
        rc->p_priv->s_flags = 0;
   for the priv struct shared by all user processes in get_priv(). this
   should only be done once. doing a SYS_PRIV_USER in sys_privctl()
   caused the flags of all user processes to be reset, so they were no
   longer PREEMPTIBLE. this happened when RS executed a policy script.
   (this broke test1 in the test set)

 VFS/MFS:
 . chown can change the mode of a file, and chmod arguments are only
   part of the full file mode so the full filemode is slightly magic.
   changed these calls so that the final modes are returned to VFS, so
   that the vnode can be kept up-to-date.
   (this broke test11 in the test set)

 MFS:
 . lookup() checked for sizeof(string) instead of sizeof(user_path),
   truncating long path names
   (caught by test 23)
 . truncate functions neglected to update ctime
   (this broke test16)

 VFS:
 . corner case of an empty filename lookup caused fields of a request
   not to be filled in in the lookup functions, not making it clear
   that the lookup had failed, causing messages to garbage processes,
   causing strange failures.
   (caught by test 30)
 . trust v_size in vnode when doing reads or writes on non-special
   files, truncating i/o where necessary; this is necessary for pipes,
   as MFS can't tell when a pipe has been truncated without it being
   told explicitly each time.
   when the last reader/writer on a pipe closes, tell FS about
   the new size using truncate_vn().
   (this broke test 25, among others)
 . permission check for chdir() had disappeared; added a
   forbidden() call
   (caught by test 23)

new code, shouldn't change anything:
 . introduced RTS_SET, RTS_UNSET, and RTS_ISSET macro's, and their
   LOCK variants. These macros set and clear the p_rts_flags field,
   causing a lot of duplicated logic like

       old_flags = rp->p_rts_flags;            /* save value of the flags */
       rp->p_rts_flags &= ~NO_PRIV;
       if (old_flags != 0 && rp->p_rts_flags == 0) lock_enqueue(rp);

   to change into the simpler

       RTS_LOCK_UNSET(rp, NO_PRIV);

   so the macros take care of calling dequeue() and enqueue() (or lock_*()),
   as the case may be). This makes the code a bit more readable and a
   bit less fragile.
 . removed return code from do_clocktick in CLOCK as it currently
   never replies
 . removed some debug code from VFS
 . fixed grant debug message in device.c
 
preemptive checks, tests, changes:
 . added return code checks of receive() to SYSTEM and CLOCK
 . O_TRUNC should never arrive at MFS (added sanity check and removed
   O_TRUNC code)
 . user_path declared with PATH_MAX+1 to let it be null-terminated
 . checks in MFS to see if strings passed by VFS are null-terminated
 
 IS:
 . static irq name table thrown out
2007-02-01 17:50:02 +00:00
Ben Gras
6f77685609 Split of architecture-dependent and -independent functions for i386,
mainly in the kernel and headers. This split based on work by
Ingmar Alting <iaalting@cs.vu.nl> done for his Minix PowerPC architecture
port.

 . kernel does not program the interrupt controller directly, do any
   other architecture-dependent operations, or contain assembly any more,
   but uses architecture-dependent functions in arch/$(ARCH)/.
 . architecture-dependent constants and types defined in arch/$(ARCH)/include.
 . <ibm/portio.h> moved to <minix/portio.h>, as they have become, for now,
   architecture-independent functions.
 . int86, sdevio, readbios, and iopenable are now i386-specific kernel calls
   and live in arch/i386/do_* now.
 . i386 arch now supports even less 86 code; e.g. mpx86.s and klib86.s have
   gone, and 'machine.protected' is gone (and always taken to be 1 in i386).
   If 86 support is to return, it should be a new architecture.
 . prototypes for the architecture-dependent functions defined in
   kernel/arch/$(ARCH)/*.c but used in kernel/ are in kernel/proto.h
 . /etc/make.conf included in makefiles and shell scripts that need to
   know the building architecture; it defines ARCH=<arch>, currently only
   i386.
 . some basic per-architecture build support outside of the kernel (lib)
 . in clock.c, only dequeue a process if it was ready
 . fixes for new include files

files deleted:
 . mpx/klib.s - only for choosing between mpx/klib86 and -386
 . klib86.s - only for 86

i386-specific files files moved (or arch-dependent stuff moved) to arch/i386/:
 . mpx386.s (entry point)
 . klib386.s
 . sconst.h
 . exception.c
 . protect.c
 . protect.h
 . i8269.c
2006-12-22 15:22:27 +00:00
David van Moolenbroek
d4e6fe3546 Setjmp/longjmp updates and cleanup. 2006-12-08 16:23:18 +00:00
Ben Gras
7195fe3325 System statistical and call profiling
support by Rogier Meurs <rogier@meurs.org>.
2006-10-30 15:53:38 +00:00
Ben Gras
65a1d21963 Part of wait()/waitpid() fix in revision 2629:2634 in PM - kernel
unblocks a process that has no priority (stopped with sys_nice()
and PRIO_STOP) and reschedules it if that gives it RTS flags of 0.
2006-10-25 13:38:31 +00:00