Commit graph

1387 commits

Author SHA1 Message Date
David van Moolenbroek
24ec0d73b5 Clean up interface to PM and VFS
- introduce new call numbers, names, and field aliases;
- initialize request messages to zero for all ABI calls;
- format callnr.h in the same way as com.h;
- redo call tables in both servers;
- remove param.h namespace pollution in the servers;
- make brk(2) go to VM directly, rather than through PM;
- remove obsolete BRK, UTIME, and WAIT calls;
- clean up path copying routine in VFS;
- move remaining system calls from libminlib to libc;
- correct some errno-related mistakes in libc routines.

Change-Id: I2d8ec5d061cd7e0b30c51ffd77aa72ebf84e2565
2014-03-01 09:05:01 +01:00
David van Moolenbroek
2c8310fce6 VFS: store m_out as part of worker thread state
There is no need to pass pointers around when there is a structure
available that already stores other similar state, such as m_in.

Change-Id: I3164c5c55c71f443688103d1f0756c086eb05974
2014-03-01 09:05:00 +01:00
David van Moolenbroek
d8106f7f1d Rename VFS_BASE to FS_BASE
The recipients of these requests are file systems, not VFS.

Change-Id: I49211cfe4289df25b0c07171c7f8c321fc3731d6
2014-03-01 09:05:00 +01:00
David van Moolenbroek
87c599da2d PM/VFS protocol: prefix with VFS_PM_
These calls are sent to VFS, and thus should be prefixed with VFS_.
Clean up the protocol and PM's main function a bit.

Since the protocol is substantially big and different from normal VFS
requests, this protocol retains its own numbering range for now.

Change-Id: Ia62104b5c5c929ed787144816d2e4cc70bed3b0b
2014-03-01 09:05:00 +01:00
David van Moolenbroek
44d3230e40 For common calls, give servers unique call numbers
The getsysinfo(2), getrusage(2), and svrctl(2) calls used the same
call number to different services. Since we want to give each service
its own call number ranges, this is no longer tenable. This patch
introduces per-service call numbers for these calls.

Note that the remainder of the COMMON_ range is left intact, as these
the remaining requests in it are processed by SEF and thus server-
agnostic. The range should really be prefixed with SEF_ now.

Change-Id: I80d728bbeb98227359c525494c433965b40fefc3
2014-03-01 09:05:00 +01:00
David van Moolenbroek
80bd109cd3 libsys: various updates
- move system calls for use by services from libminlib into libsys;
- move srv_fork(2) and srv_kill(2) from RS and into libsys;
- replace getprocnr(2) with sef_self(3);
- rename previous getnprocnr(2) to getprocnr(2);
- clean up getepinfo(2);
- change all libsys calls that used _syscall to use _taskcall, so as
  to avoid going through errno to pass errors; this is already how
  most calls work anyway, and many of the calls previously using
  _syscall were already assumed to return the actual error;
- initialize request messages to zero, for future compatibility
  (note that this does not include PCI calls, which are in need of a
  much bigger overhaul, nor kernel calls);
- clean up more of dead DS code as a side effect.

Change-Id: I8788f54c68598fcf58e23486e270c2d749780ebb
2014-03-01 09:05:00 +01:00
David van Moolenbroek
efd3487bc5 PM: send replies immediately
The original delayed reply functionality was there to support swapping
in processes as they are unblocked, but swap support is long gone.
These days, this code only incurs overhead and hides bugs.

Change-Id: I4aebcd80719daa1bec45ac91975ddc9a460d74d4
2014-03-01 09:05:00 +01:00
David van Moolenbroek
f310aefcbd PM: resolve fork/kill race condition
When a process forks, VFS is informed on behalf of the child. This is
correct, because otherwise signals to the new child could get lost.
However, that means that the parent is not blocked from being killed
by a signal while the child is blocked on this VFS call. As a result,
by the time that the VFS reply comes in, the parent may already be
dead, and the child may thus have been assigned a new parent: INIT.

Previously, PM would blindly reply to the parent when the VFS reply
for the fork came in. Thus, it could end up sending a reply to INIT,
even though INIT did not issue the fork(2) call. This could end up
satisfying a different call from INIT (typically waitpid(2)) and then
cause an error when that other call was complete.

It would be possible to set VFS_CALL on both forking parent and child.
This patch instead adds a flag (NEW_PARENT) to note that a process's
parent has changed during a VFS call.

Change-Id: Iad930b2e441db54fe6f7d2fd011f0f6a26e2923d
2014-03-01 09:04:59 +01:00
David van Moolenbroek
595d73a896 PM: rework signal handling
- introduce PROC_STOPPED flag, which tracks whether the process is
  stopped on PROC_STOP in the kernel, rather than implicitly deriving
  this from PM_SIG_PENDING;
- make the process resumption test based on current state rather than
  state transitions;
- add and clarify several flag checks in the signal handling code;
- add test79 to test signal handling robustness.

Change-Id: Ic8c7527095035b300b56f2ab1b9dd190bd4bf001
2014-03-01 09:04:59 +01:00
David van Moolenbroek
4d4e70daaa PM: remove obsolete ALARM, PAUSE, TIMES calls
NetBSD libc implements these as wrappers around setitimer(2),
sigsuspend(2), and getrusage(2), respectively.

Change-Id: I0c5e725b3e1316bddd3a3ff7ef65d57d30afd10d
2014-03-01 09:04:59 +01:00
David van Moolenbroek
f30a16b159 Remove support for MKTRACE, MKMCONTEXT, MKSTATECTL
Change-Id: Ib5fa53913ecb7b46d30d391dbdd3e8ef21eb2254
2014-03-01 09:04:59 +01:00
Ben Gras
6c8f7fc3ba netbsd dirent.h, import sys/sys *.h, mfs cleanup
. add all sys/sys headers not already present to help compiling
	. take netbsd dirent.h and struct dirent; main result is
	  introducing d_type and d_namlen that have to be set by getdents()
	  in all FS code implementing it
	. d_off is gone
	. alignment of the struct has become 8 bytes instead of 4
	. remove _MAX_BLOCK_SIZE, _MIN_BLOCK_SIZE, _STATIC_BLOCK_SIZE
	. libminlib: cleanup unused yet duplicate code
	. mfs: throw out the long-broken v1, v2 support
	. new test for dirent contents filled by getdents()

Change-Id: I1459755c7ba5e5d1c9396d3a587ce6e63ddc283e
2014-03-01 09:04:59 +01:00
David van Moolenbroek
664b726cd3 VFS: further cleanup of device code
- all TTY-related exceptions have now been merged into the regular
  code paths, allowing non-TTY drivers to expose TTY-like devices;
- as part of this, CTTY_MAJOR is now fully managed by VFS instead of
  being an ugly stepchild of the TTY driver;
- device styles have become completely obsolete, support for them has
  been removed throughout the system; same for device flags, which had
  already become useless a while ago;
- device map open/close and I/O function pointers have lost their use,
  thus finally making the VFS device code actually readable;
- the device-unrelated pm_setsid has been moved to misc.c;
- some other small cleanup-related changes.

Change-Id: If90b10d1818e98a12139da3e94a15d250c9933da
2014-03-01 09:04:58 +01:00
David van Moolenbroek
cf12dbac0d IS: dump number of in-use FDs for VFS
Change-Id: If0e2092d5a8c384c31b1f44cc0591bb119c6d8de
2014-03-01 09:04:58 +01:00
David van Moolenbroek
e5cc85fdc4 Extend dupfrom(2) into copyfd(2)
This single function allows copying file descriptors from and to
processes, and closing a previously copied remote file descriptor.
This function replaces the five FD-related UDS backcalls. While it
limits the total number of in-flight file descriptors to OPEN_MAX,
this change greatly improves crash recovery support of UDS, since all
in-flight file descriptors will be closed instead of keeping them
open indefinitely (causing VFS to crash on system shutdown). With the
new copyfd call, UDS becomes simpler, and the concept of filps is no
longer exposed outside of VFS.

This patch also moves the checkperms(2) stub into libminlib, thus
fully abstracting away message details of VFS communication from UDS.

Change-Id: Idd32ad390a566143c8ef66955e5ae2c221cff966
2014-03-01 09:04:58 +01:00
David van Moolenbroek
50685cbec3 VFS: better dupfrom(2) deadlock detection
Change-Id: I29f00075698888c7c8ca60b47ab82fba8c606f4e
2014-03-01 09:04:58 +01:00
David van Moolenbroek
b003ed0929 UDS: split off from PFS
Change-Id: I769cbd64aa6e5e85a797caf0f8bbb4c20e145263
2014-03-01 09:04:57 +01:00
David van Moolenbroek
89332ecdf1 system.conf: subsystem VID/DID matching support
- change "vid/did" to "vid:did", old form still supported for now;
- allow "vid:did/subvid:subdid" specification in system.conf, in
  which case a device will be visible to a driver if the subsystem
  VID/DID also match.

Change-Id: I7aef54da1b0bc81e24b5d98f1a28416f38f8b266
2014-03-01 09:04:57 +01:00
David van Moolenbroek
6b3f4dc157 Input infrastructure, INPUT server, PCKBD driver
This commit separates the low-level keyboard driver from TTY, putting
it in a separate driver (PCKBD). The commit also separates management
of raw input devices from TTY, and puts it in a separate server
(INPUT). All keyboard and mouse input from hardware is sent by drivers
to the INPUT server, which either sends it to a process that has
opened a raw input device, or otherwise forwards it to TTY for
standard processing.

Design by Dirk Vogt. Prototype by Uli Kastlunger.

Additional changes made to the prototype:

- the event communication is now based on USB HID codes; all input
  drivers have to use USB codes to describe events;
- all TTY keymaps have been converted to USB format, with the effect
  that a single keymap covers all keys; there is no (static) escaped
  keymap anymore;
- further keymap tweaks now allow remapping of literally all keys;
- input device renumbering and protocol rewrite;
- INPUT server rewrite, with added support for cancel and select;
- PCKBD reimplementation, including PC/AT-to-USB translation;
- support for manipulating keyboard LEDs has been added;
- keyboard and mouse multiplexer devices have been added to INPUT,
  primarily so that an X server need only open two devices;
- a new "libinputdriver" library abstracts away protocol details from
  input drivers, and should be used by all future input drivers;
- both INPUT and PCKBD can be restarted;
- TTY is now scheduled by KERNEL, so that it won't be punished for
  running a lot; without this, simply running "yes" on the console
  kills the system;
- the KIOCBELL IOCTL has been moved to /dev/console;
- support for the SCANCODES termios setting has been removed;
- obsolete keymap compression has been removed;
- the obsolete Olivetti M24 keymap has been removed.

Change-Id: I3a672fb8c4fd566734e4b46d3994b4b7fc96d578
2014-03-01 09:04:55 +01:00
Thomas Cort
f5dbfe789e uname: normalize release and version
Most systems provide the full version number in the
'release' field and the kernel version in 'version'.
Minix used to split the full version number between
release and version which caused problems for pkgsrc
and other applications. This patch brings Minix's
uname in line with other systems such as NetBSD.
It also brings the getty banner in line with NetBSD.

Old Minix uname:
	sysname->Minix
	nodename->10.0.2.15
	release->3
	version->2.1
	machine->i686

New Minix uname:
	sysname->Minix
	nodename->10.0.2.15
	release->3.2.1
	version->Minix 3.2.1 (GENERIC)
	machine->i686

Change-Id: I966633dfdcf2f9485966bb0d0d042afc45bbeb7d
2014-03-01 09:04:55 +01:00
David van Moolenbroek
36ac0dbcf8 Take LOG out of the boot image
Change-Id: Id2629776b53aae46629b04a42c15cbbacac9b949
2014-03-01 09:04:55 +01:00
David van Moolenbroek
de975579a4 Rename SYSCTL kernel call to DIAGCTL
Change-Id: I1b17373f01808d887dcbeab493838946fbef4ef6
2014-03-01 09:04:54 +01:00
Lionel Sambuc
9fab85c2de Replacing timer_t by netbsd's timer_t
* Renamed struct timer to struct minix_timer
 * Renamed timer_t to minix_timer_t
 * Ensured all the code uses the minix_timer_t typedef
 * Removed ifdef around _BSD_TIMER_T
 * Removed include/timers.h and merged it into include/minix/timers.h
 * Resolved prototype conflict by renaming kernel's (re)set_timer
   to (re)set_kernel_timer.

Change-Id: I56f0f30dfed96e1a0575d92492294cf9a06468a5
2014-03-01 09:04:54 +01:00
David van Moolenbroek
dba2d1f8b4 VFS: add dupfrom(2) call
This call copies a file descriptor from a remote process into the
calling process. The call is for the VND driver only, and in the
future, ACLs will prevent any other process from using this call.

Change-Id: Ib16fdd1f1a12cb38a70d7e441dad91bc86898f6d
2014-03-01 09:04:54 +01:00
David van Moolenbroek
b48542d914 VM: readd support for forgetting cached FS blocks
Not all services involved in block I/O go through VM to access the
blocks they need.  As a result, the blocks in VM may become stale,
possibly causing corruption when the stale copy is restored by a
service that does go through VM later on.  This patch restores support
for forgetting cached blocks that belong to a particular device, and
makes the relevant file systems use this functionality 1) when
requested by VFS through REQ_FLUSH, and 2) upon unmount.

Change-Id: I0758c5ed8fe4b5ba81d432595d2113175776aff8
2014-03-01 09:04:53 +01:00
David van Moolenbroek
665198b4c2 Rewrite character driver protocol
As a side effect, remove the clone style, as the normal device style
supports device cloning now.

Change-Id: Ie82d1ef0385514a04a8faa139129a617895780b5
2014-03-01 09:04:52 +01:00
David van Moolenbroek
87337273e4 Remove support for reopening character devices
Previously, VFS would reopen a character device after a driver crash
if the associated file descriptor was opened with the O_REOPEN flag.
This patch removes support for this feature. The code was complex,
full of uncovered corner cases, and hard to test. Moreover, it did not
actually hide the crash from user applications: they would get an
error code to indicate that something went wrong, and have to decide
based on the nature of the underlying device how to continue.

- remove support for O_REOPEN, and make playwave(1) reopen its device;
- remove support for the DEV_REOPEN protocol message;
- remove all code in VFS related to reopening character devices;
- no longer change VFS filp reference count and FD bitmap upon filp
  invalidation; instead, make get_filp* fail all calls on invalidated
  FDs except when obtained with the locktype VNODE_OPCL which is used
  by close_fd only;
- remove the VFS fproc file descriptor bitmap entirely, returning to
  the situation that a FD is in use if its slot points to a filp; use
  FILP_CLOSED as single means of marking a filp as invalidated.

Change-Id: I34f6bc69a036b3a8fc667c1f80435ff3af56558f
2014-03-01 09:04:52 +01:00
David van Moolenbroek
a4277506a2 VFS: rework device code
- block the calling thread on character device close;
- fully separate block and character open/close routines;
- reuse generic open/close code for the cloning case;
- zero all messages to drivers before filling them;
- use appropriate types for major/minor device numbers.

Change-Id: Ia90e6fe5688f212f835c5ee1bfca831cb249cf51
2014-03-01 09:04:52 +01:00
David van Moolenbroek
f6915d3dee Make PFS backcalls regular VFS calls
- prefix them with VFS_ as they are going to VFS;
- give these calls normal call numbers;
- give them their own set of message field aliases;
- also make do_mapdriver a regular call.

Change-Id: I2140439f288b06d699a1f65438bd8306509b259e
2014-03-01 09:04:52 +01:00
David van Moolenbroek
701f2b4dd5 VFS: select(2) fixes
- check each file descriptor's open access mode (filp_mode);
- treat an error returned by a character driver as a select error;
- check all filps in each set before finishing select;
- do not copy back file descriptor sets if an error occurred;
- remove the hardcoded list of supported character major devices,
  since all drivers should now be capable of responding properly;
- add tests to test40 and fix its error count aggregation.

Change-Id: I57ef58d3afb82640fc50b59c859ee4b25f02db17
2014-03-01 09:04:51 +01:00
David van Moolenbroek
4628a14fc7 libnetsock: use libchardriver
Change-Id: Ia5b780cad0b0c636db9bd866c7223da0d38ef6ea
2014-03-01 09:04:51 +01:00
David van Moolenbroek
15e83fec25 LWIP: move chardev message parsing into libnetsock
Change-Id: Ie23fd003c9fa35811548f388c8e9b55e8d9de8d7
2014-03-01 09:04:51 +01:00
David van Moolenbroek
94f7151729 INET: use libchardriver
Change-Id: Icf8a1a5769ce0aede1cc28da99b9daf7d328182c
2014-03-01 09:04:51 +01:00
David van Moolenbroek
ddeb562e1a PFS: use libchardriver; clean up
- simplify and repair UDS request handling state machine;
- simplify interface used between internal modules;
- implement missing support for nonblocking I/O;
- fix select implementation;
- clean up global variables.

Change-Id: Ia82c5c6f05cc3f0a498efc9a26de14b1cde6eace
2014-03-01 09:04:51 +01:00
David van Moolenbroek
95624ae072 Block protocol: add user endpoint to IOCTL request
I/O control requests now come with the endpoint of the user process
that initiated the ioctl(2) call. It is stored in a new BDEV_USER
field, which is an alias for BDEV_FLAGS. The contents of this field
are to be used only in highly specific situations. It should be
preserved (not replaced!) by services that forward IOCTL requests,
and may be set to NONE for service-initiated IOCTL requests.

Change-Id: I68a01b9ce43eca00e61b985a9cf87f55ba683de4
2014-02-19 11:22:15 +01:00
David van Moolenbroek
113635b019 Block protocol: use own [RW]_BIT definitions
The original R_BIT and W_BIT definitions have nothing to do with the
way these bits are used. Their distinct usage is more apparent when
they have different names.

Change-Id: Ia984457f900078b2e3502ceed565fead4e5bb965
2014-02-19 11:22:15 +01:00
David van Moolenbroek
5c53b417cd VFS: update filp_pos on chardev I/O (workaround)
Previously, reading from or writing to a character device would not
update the file position on the corresponding filp object.  Performing
this update correctly is not trivial: during and after the I/O
operation, the filp object must not be locked.  Ideally, read/write
requests on a filp that is already involved in a read/write operation,
should be queued.  For now, we optimistically update the file position
at the start of the I/O; this works under the assumptions listed in
the corresponding comment.

Change-Id: I172a61781850423709924390ae3df1f2d1f94707
2014-02-18 11:25:03 +01:00
David van Moolenbroek
1e7b45c682 VFS: fix interruption of blocking pipe operations
POSIX states that when interrupted, partially successful pipe
operations should return the partial result rather than EINTR. VFS
previously wouldn't look at the partial result, and not clear it
either, which would result in a panic upon the next pipe operation.

Change-Id: Ia1eb72b4b77394051444e63a1390d49bb315eb04
2014-02-18 11:25:03 +01:00
David van Moolenbroek
723e51327f VFS: worker thread model overhaul
The main purpose of this patch is to fix handling of unpause calls
from PM while another call is ongoing. The solution to this problem
sparked a full revision of the threading model, consisting of a large
number of related changes:

- all active worker threads are now always associated with a process,
  and every process has at most one active thread working for it;
- the process lock is always held by a process's worker thread;
- a process can now have both normal work and postponed PM work
  associated to it;
- timer expiry and non-postponed PM work is done from the main thread;
- filp garbage collection is done from a thread associated with VFS;
- reboot calls from PM are now done from a thread associated with PM;
- the DS events handler is protected from starting multiple threads;
- support for a system worker thread has been removed;
- the deadlock recovery thread has been replaced by a parameter to the
  worker_start() function; the number of worker threads has
  consequently been increased by one;
- saving and restoring of global but per-thread variables is now
  centralized in worker_suspend() and worker_resume(); err_code is now
  saved and restored in all cases;
- the concept of jobs has been removed, and job_m_in now points to a
  message stored in the worker thread structure instead;
- the PM lock has been removed;
- the separate exec lock has been replaced by a lock on the VM
  process, which was already being locked for exec calls anyway;
- PM_UNPAUSE is now processed as a postponed PM request, from a thread
  associated with the target process;
- the FP_DROP_WORK flag has been removed, since it is no longer more
  than just an optimization and only applied to processes operating on
  a pipe when getting killed;
- assignment to "fp" now takes place only when obtaining new work in
  the main thread or a worker thread, when resuming execution of a
  thread, and in the special case of exiting processes during reboot;
- there are no longer special cases where the yield() call is used to
  force a thread to run.

Change-Id: I7a97b9b95c2450454a9b5318dfa0e6150d4e6858
2014-02-18 11:25:03 +01:00
David van Moolenbroek
4f6b382c41 Retire ptrace(T_DUMPCORE), dumpcore(1), gcore(1)
The T_DUMPCORE implementation was not only broken - it would currently
produce a coredump of the tracer process rather than the traced
process - but also deeply flawed, and fixing it would require serious
alteration of PM's internal state machine. It should be possible to
implement the same functionality in userland, and that is now the
suggested way forward. For now, also remove the (identical) utilities
using T_DUMPCORE: dumpcore(1) and gcore(1).

Change-Id: I1d51be19c739362b8a5833de949b76382a1edbcc
2014-02-18 11:25:03 +01:00
David van Moolenbroek
f707937192 VFS: process char driver replies from main thread
Previously, processing of some replies coming from character drivers
could block on locks, and therefore, such processing was done from
threads that were associated to the character driver process. The
hidden consequence of this was that if all threads were in use, VFS
could drop replies coming from the driver. This patch returns VFS to
a situation where the replies from character drivers are processed
instantly from the main thread, by removing the situations that may
cause VFS to block while handling those replies.

- change the locking model for select, so that it will never block
  on any processing that happens after the select call has been set
  up, in particular processing of character driver select replies;
- clearly mark all select routines that may never block;
- protect against race conditions in do_select as result of the
  locking that still does happen there (as is required for pipes);
- also handle select timers from the main thread;
- move processing of character driver replies into device.c.

Change-Id: I4dc8e69f265cbd178de0fbf321d35f58f067cc57
2014-02-18 11:25:03 +01:00
David van Moolenbroek
2e9f4d0198 VFS: properly cancel select queries on unpause
Change-Id: I16e71db3f5c1bcc7ba6045bc9f02b13d71dc31eb
2014-02-18 11:25:03 +01:00
David van Moolenbroek
87aefd7eb2 VFS: remove support for sync char driver protocol
Change-Id: I57cc870a053b813b3a3fc45da46606ea84fe4cb1
2014-02-18 11:25:03 +01:00
David van Moolenbroek
c7fbafe1ad VFS: remove FP_BLOCKED_ON_DOPEN
These days, DEV_OPEN calls to character drivers block the calling
thread until completion or failure, and thus never return SUSPEND to
the caller. The same already applied to BDEV_OPEN calls to block
drivers. It has thus become impossible for a process to enter a state
of being blocked on a device open call.

There is currently no support for restarting device open calls to
restarted character drivers. This support was present in the _DOPEN
logic, but was already no longer triggering. In the future, this case
should be handled by the thread performing the open request.

Change-Id: I6cc1e7b4c9ed116c6ce160b315e6e060124dce00
2014-02-18 11:25:03 +01:00
David van Moolenbroek
784cdd4d07 PFS: remember request information for IOCTLs
Not doing so caused PFS to commit protocol violations by relying on
stale information when sending replies. This stale information always
happened to be correct, which is why the problem went unnoticed.
Change-Id: Ia42ca670718d6e731193cd2c34a3ff455f8a94d3
2014-02-18 11:25:02 +01:00
David van Moolenbroek
6331e8f845 Retire the synchronous character driver protocol
- change all sync char drivers into async drivers;
- retire support for the sync protocol in libchardev;
- remove async dev style, as this is now the default;
- remove dev_status from VFS;
- clean up now-unused protocol messages.

Change-Id: I6aacff712292f6b29f2ccd51bc1e7d7003723e87
2014-02-18 11:25:02 +01:00
David van Moolenbroek
97172a1db0 Sync char protocol: add nonblocking transfer flag
The async char protocol already has this, so this patch closes the
gap between the two protocols a bit. Support for this flag has been
added to all sync char drivers that support CANCEL at all.

The LOG driver was already using the asynchronous protocol, but it
did not support the nonblocking transfer flag. This has been fixed
as well.

Change-Id: Ia55432c9f102765b59ad3feb45a8bd47a782c93f
2014-02-18 11:25:02 +01:00
David van Moolenbroek
a75c47e5ac VFS: set w_drv_sendrec only when needed
As with w_task, this ensures that the field remains cleared if it is
not used. Without this, worker_stop could mistakenly identify a thread
as talking to a device driver rather than a (crashed) file server.

Change-Id: I7d3ebed3efc3cd4f5c891f61c67a6463109b6376
2014-02-18 11:25:02 +01:00
Thomas Veerman
7d02ecdbb4 VFS: set w_task only when needed
It was always set, but not always cleared, when talking to asynchronous
drivers. This could cause erratic behavior upon a driver crash.

Normally, a worker thread's w_task field is set when it's about to
communicate with a driver or FS. Then upon receiving a reply we can
do sanity checks (that the thread we want to wake up was actually
waiting for a reply). Also, when a driver/FS crashes, we can identify
which worker threads were talking to the crashed endpoint and handle
the error gracefully.

Asynchronous drivers are a bit special, though. In most cases, the
sender of the request is not interested in the reply (the sender was
suspended and only wants to know whether the request was successfully
caried out or not). However, the open request is special, as the reply
carries information needed by the sender. This is the only request
where a worker thread actually yields and waits for the result. This is
also the only case where we're interested in setting w_task for
asynchronous drivers.

Change-Id: Ia1ce2747937df376122b5e13b6a069de27fcc379
2014-02-18 11:25:02 +01:00
Lionel Sambuc
cfd3379bb1 Removing CSU patches
* Removed startup code patches in lib/csu regarding kernel to userland
   ABI.

 * Aligned stack layout on NetBSD stack layout.

 * Generate valid stack pointers instead of offsets by taking into account
   _minix_kerninfo->kinfo->user_sp.

 * Refactored stack generation, by moving part of execve in two
   functions {minix_stack_params(), minix_stack_fill()} and using them
   in execve(), rs and vm.

 * Changed load offset of rtld (ld.so) to:
      execi.args.stack_high - execi.args.stack_size - 0xa00000
   which is 10MB below the main executable stack.

Change-Id: I839daf3de43321cded44105634102d419cb36cec
2014-02-18 11:25:02 +01:00