Without this patch, calling sys_mq_open() with same names specified
results in two separate queues being opened and their descriptors
returned instead of the same descriptor being returned for both.
Do the initialisation and comparison properly, so that when the
same name is specified to sys_mq_open multiple times in same
process or different process, the same opened queue descriptor is
returned.
This patch adds functionality to request an asynchronous notification
if some other process has send a message to it. We currently send a
SIGALRM to avoid any changes to core infrastructure of signal handling.
Ideally we should implement a separate signal for this. Currently there
is an obvious disadvantage of not being able to use SIGALRM with alarm,
if we are using this functionality.
Currently we only allow users to get and set number of queues. The
operation is always non blocking. There is no provision for non
blocking operation at the moment.
The queue sizes are set to MAX 256 by default. If a user changes the
attributes and sets the queue size or number of messages in a queue
to less than 256, it is the responsibility of the user to close any
queues which were opened with a descriptor greater than the value
currently set.
For example, by default queue sizes are 256. If 150 queues are opened
and then the user sets the number of queues to 32, all open descriptors
and queues from 32 to 150 must be closed. Note that descriptor number
allocation starts with zero and not one.
Functional specification mandates returning a message with a higher
timestamp in case two messages have the same priority. Somehow we
missed this in the implementation. This also introduced a bug where
all messages with same priority could cause problems.
Fixed the following bugs:
1. Message priority was not set at all at two places
2. Limits check was not correct while returning error values
3. We are suppose to allow multiple users operate on the same queue
using a named descriptor. However any one user calling close before
the other would result in closing the queue even when other users
might be using it. Track number of users and close only if number of
users is zero. Yet to do functional tests for this, so this is untested,
but introduce it anyway at this juncture.
This patch allows user processes to send messages to kernel. Without
this change, trying to do a system call for using message queues like
sys_mq_open will fail with ECALLDENIED error number -210.
Implement message queues support for Minix.
Pending tasks:
Blocking or non blocking for send receive?
Sort by priority and time?
Test codes?
Bug fixes?
This commit adds preparatory support for forthcoming message
queue implementation to the Minix kernel. The core implementation
will be added with the next commit.
The CD now boots directly from the ISO 9660 filesystem instead of using
MBR partitioning with Minix file systems. This saves some space on the
CD and reduces memory requirements by some unknown amount as the root
ramdisk is completely eliminated.
The x86 hard drive image creation is also rewritten in the same
fashion.
The setup is modified to be more NetBSD-like (unpacking sets
tarballs instead of blindly copying the CD contents). Splitting MINIX
into sets is done in another commit due to it being a nightmare to
rebase.
Since MINIX lacks union mounts for now, a bunch of ramdisks are
generated at run-time to make parts of the filesystem writeable for the
CD. This solution isn't ideal, but it's enough for an installation CD.
Change-Id: Icbd9cca4dafebf7b42c345b107a17679a622d5cd
isofs now uses an in-memory directory listing built on-the-fly instead
of parsing the ISO 9660 data structures over and over for almost every
request. This yields huge performance improvements.
The directory listing is allocated dynamically, but Minix servers aren't
normally supposed to do that because critical servers would crash if the
system runs out of memory. isofs is quite frugal, won't allocate memory
after having the whole directory tree cached and is not that critical
(its most important job is to serve as a root file system during
installation).
The benefits and elegance of this scheme far outweights this small
problem in practice.
Change-Id: I13d070388c07d274cbee0645cbc50295c447c5b6
This patch adds support for the wait4 system call, and with that the
wait3 call as well. The implementation is absolutely minimal: only
user and system times of the exited child are returned (with all other
rusage fields left zero), and there is no support for tracers. Still,
this should cover the main use cases of wait4.
Change-Id: I7a04589a8423a23990ab39aa38e85d535556743a
- the userland call is now made to PM only, and PM relays the call to
other servers as appropriate; this is an ABI change that will
ultimately allow us to add proper support for wait3() and the like;
for the moment there is backward compatibility;
- the getrusage-specific kernel subcall has been removed, as it
provided only redundant functionality, and did not provide the means
to be extended correctly in the future - namely, allowing the kernel
to return different values depending on whether resource usage of
the caller (self) or its children was requested;
- VM is now told whether resource usage of the caller (self) or its
children is requested, and it refrains from filling in wrong values
for information it does not have;
- VM now uses the correct unit for the ru_maxrss values;
- VFS is cut out of the loop entirely, since it does not provide any
values at the moment; a comment explains how it should be readded.
Change-Id: I27b0f488437dec3d8e784721c67b03f2f853120f
The current value was both wrong (counting spawned kernel signals
rather than delivered user signals) and returned for the calling
process even if the request was for the process's children.
For now we are better off not populating this field at all.
Change-Id: I6c660be266b5746b7c3db57ae88fa7f872961ee2
The current values were both inaccurate (especially for dynamically
linked executables) and using the wrong unit (bytes, instead of
kilobytes times ticks-of-execution). For now we are better off not
populating these fields at all.
Change-Id: I195a8fa8db909e64a833eec25f59c9ee0b89bdc5
POSIX states that times() and getrusage() should only return child
user and system times of terminated children for which wait*() has
returned their PIDs.
Change-Id: I38e19ad71543a3b91e944bef8e4e1bd903de51bf
- move MINIX3-specific files into minix/lib/libpuffs;
- resynchronize the remaining files with NetBSD code;
- remove a few unnecessary changes;
- put remaining MINIX3-specific changes in __minix blocks;
- sort out the source files being linked at all.
The result is that libpuffs now successfully links against FUSE
file system programs again. It can successfully mount, perform
some of the most basic operations, and unmount the file system.
Change-Id: Ieac220f7ad8c4d1fa293abda81967e8045be0bb4
- no longer inject fewer faults than instructed;
- no longer apply a limit on the number of injected faults;
- refactory to allow for random faults (type 99);
- also allow for stop faults (type 50);
- massive dead code cleanup;
- move outdated test cruft into tests/ subdirectory; it is kept only
as an example of how to use swifi.
Change-Id: I8a3cb71902dfaadb7bf785723b917307db83d0d5
At the very least, these can be used to test for the existence of
files not normally accessible by unprivileged users.
Change-Id: I054cf6d033a1604bbbc871db37103a67067abe84
- move from minix/commands to minix/usr.sbin;
- install into /usr/sbin instead of /usr/bin;
- move manual page into source directory;
- resolve compilation warning;
- convert to KNF.
Change-Id: I1206b52e8804a68a3a80f6d7f63916e7fcdc9e3f
- move from minix/commands to minix/usr.sbin;
- install into /usr/sbin instead of /usr/bin;
- move manual page into source directory;
- resolve compilation warning;
- convert to KNF.
Change-Id: Iccb4a8b27ae220254bae19e9198478b40706f542
- move from minix/commands to minix/usr.sbin;
- install into /usr/sbin instead of /usr/bin;
- move manual page into source directory;
- resolve compilation warning;
- convert to KNF.
Change-Id: I08c16998bd499a468799a6587f6fe45f42590461
Various generic file IOCTL calls should be processed by VFS rather
than individual drivers. For this reason, we rewrite them to use
fcntl(2) instead.
Change-Id: I38a5f3c7b21943a897114a51678a800f7e7f0a77
Currently, the userland ABI uses a single field ('user_sp') far
into the very large 'kinfo' structure on the shared kernel
information page. This precludes us from modifying or getting
rid of 'kinfo' in the future without breaking userland. This
patch adds a separate 'kuserinfo' structure to the kernel
information page, with only information that is part of the
userland ABI, in an extensible manner. Userland now uses this
field if it is present, and falls back to the old field if not.
Change-Id: Ib7b24b53a440f40a2edc28cdfa48447ac2179288
This change serves to reduce the clutter inside the top-level kerninfo
structure, and allows other ARM-specific values to be added on the
kernel page in one place.
Change-Id: I36a6aada9dbd1230b25014728be675d389088667
Please note that this information is for use by system services only!
The clock facility is not ready to be used directly by userland, and
thus, this kernel page extension is NOT part of the userland ABI.
For service programmers' convenience, change the prototype of the
getticks(3) to return the uptime clock value directly, since the call
can no longer fail.
Correct the sys_times(2) reply message to use the right field type
for the boot time.
Restructure the kernel internals a bit so as to have all the clock
stuff closer together.
Change-Id: Ifc050b7bd253aecbe46e3bd7d7cc75bd86e45555
Instead of importing an external _minix_kerninfo variable, any code
using the shared kernel page should now call get_minix_kerninfo(3).
Since this is the only logical name for such a function, rename the
previous get_minix_kerninfo call to ipc_minix_kerninfo.
Change-Id: I2e424b6fb55aa55d3da850187f1f7a0b7cbbf910
This commits adds a basic infrastructure to support Address Space
Randomization (ASR). In a nutshell, using the already imported ASR
LLVM pass, multiple versions can be generated for the same system
service, each with a randomized, different address space layout.
Combined with the magic instrumentation for state transfer, a system
service can be live updated into another ASR-randomized version at
runtime, thus providing live rerandomization.
Since MINIX3 is not yet capable of running LLVM linker passes, the
ASR-randomized service binaries have to be pregenerated during
crosscompilation. These pregenerated binaries can then be cycled
through at runtime. This patch provides the basic proof-of-concept
infrastructure for both these parts.
In order to support pregeneration, the clientctl host script has
been extended with a "buildasr" command. It is to be used after
building the entire system with bitcode and magic support, and will
produce a given number of ASR-randomized versions of all system
services. These services are placed in /usr/service/asr in the
image that is generated as final step by the "buildasr" command.
In order to support runtime updating, a new update_asr(8) command
has been added to MINIX3. This command attempts to live-update the
running system services into their next ASR-randomized versions.
For now, this command is not run automatically, and thus must be
invoked manually.
Technical notes:
- For various reasons, magic instrumentation is x86-only for now,
and ASR functionality is therefore to be used on x86 only as well.
- The ASR-randomized binaries are placed in numbered subdirectories
so as not to have to change their actual program names, which are
assumed to be static in various places (system.conf, procfs).
- The root partition is typically too small to contain all the
produced binaries, which is why we introduce /usr/service. There
is a symlink from /service/asr to /usr/service/asr for no other
reason than to let userland continue to assume that all services
are reachable through /service.
- The ASR count field (r_asr_count/ASRcount) maintained by RS is not
used within RS in any way; it is only passed through procfs to
userland in order to allow update_asr(8) to keep track of which
version is currently loaded without having to maintain own state.
- Ideally, pre-instrumentation linking of a service would remove all
its randomized versions. Currently, the user is assumed not to
perform ASR instrumentation and then recompile system services
without performing ASR instrumentation again, as the randomized
binaries included in the image would then be stale. This aspect
has to be improved later.
- Various other issues are flagged in the comments of the various
parts of this patch.
Change-Id: I093ad57f31c18305591f64b2d491272288aa0937
Sanchayan Maity
Lionel Sambuc
Jean-Baptiste Boric
David van Moolenbroek