cinap_lenrek [Thu, 25 Dec 2014 10:30:29 +0000 (11:30 +0100)]
zynq: only tmpmap() while splhi(), remove unneeded coherence() after tmpunmap(), splhi() in l2free()
we have to call tmpmap() with interrupts disabled as the map
is a per cpu and a interrupt can preempt us while we where
commited to use a entry but *before* we wrote it!
tmpunmap() already calls coherence() before flushpg() so it
is not needed after tmpunmap().
splhi() in l2free() isnt needed as l2free() is always called
with interrupts disabled from mmuswitch() and mmurelease().
cinap_lenrek [Wed, 24 Dec 2014 19:53:58 +0000 (20:53 +0100)]
zynq: fpsave() and fpclear() both need to disable the fpu
fpsave needs to disable the fpu! otherwise we won't catch
the mathtrap() in the kernel or when context switching to
another process that will attempt to use it.
cinap_lenrek [Sun, 21 Dec 2014 16:25:55 +0000 (17:25 +0100)]
ip: exclude "don't fragment" bit from ipv4 reassembly test
other operating systems always set the "don't fragment" bit
in ther outgoing ipv4 packets causing us to unnecesarily
call ip4reassemble() looking for a fragment reassembly queue.
the change excludes the "don't fragment" bit from the test
so we now call ip4reassemble() only when the "more fragmens"
bit is set or a fragment offset other than zero is given.
cinap_lenrek [Sun, 21 Dec 2014 03:46:22 +0000 (04:46 +0100)]
kernel: avoid inconsistent reads in /proc/#/fd and /proc/#/ns
to allow bytewise access to /proc/#/fd, the contents of the file where
recreated on each call. if fd's had been closed or reassigned between
the reads, the offset would be inconsistent and a read could start off
in the middle of a line. this happens when you cat /proc/#/fd file of
a busy process that mutates its filedescriptor table.
to fix this, we now return one line record at a time. if the line
fits in the read size, then this means the next read will always start
at the beginning of the next line record. we remember the consumed
byte count in Chan.mrock and the current record in Chan.nrock. (these
fields are free to usefor non-directory files)
if a read comes in and the offset is the same as c->mrock, we do not
need to regenerate the file and just render the next c->nrock's record.
for reads smaller than the line count, we have to regenerate the content
up to the offset and the race is still possible, but this should not
be the common case.
the same algorithm is now used for /proc/#/ns file, allowing a simpler
reimplementation and getting rid of Mntwalk state strcture.
cinap_lenrek [Fri, 19 Dec 2014 22:34:43 +0000 (23:34 +0100)]
pc, pc64: untangle acpireset() from mpshutdown()
mpshutdown() used to call acpireset() making it impossible to build
a kernel without archacpi. now, mpshutdown() is a helper function
that only shuts down the application processors that gets used from
mpreset() and acpireset().
the generic machine reset code in exported by devarch's archreset()
function that is called by mpreset() and from acpireset() as a fallback.
so the code duplication that was in mpshutdown() is avoided.
cinap_lenrek [Thu, 18 Dec 2014 22:53:32 +0000 (23:53 +0100)]
kernel: remove "checked xxx page table entries" print from checkpages()
the purpose of checkpages() is to verify consitency of the hardware mmu state,
not to notify on the console that a program faulted. a program could also
continue after handling the note. (this seems to be the case in go programs)
cinap_lenrek [Wed, 17 Dec 2014 21:49:51 +0000 (22:49 +0100)]
pc, pc64: cleanup devarch
- shorten cpuidprnt so it doesnt have to break line
- addarchfile: complain when running out of entries
- fix range check in rmemrw() (harmless)
- use nil instead of 0 for pointers
cinap_lenrek [Wed, 17 Dec 2014 10:18:05 +0000 (11:18 +0100)]
boot(8): the method!server notation isnt usefull anymore...
- in 9front, the bootargs are in the form: method!device args
- remove redundant and wrong paragraphs regarding tcp booting
- document il boot method
- fix boot and bootrc confusions
cinap_lenrek [Tue, 16 Dec 2014 04:41:20 +0000 (05:41 +0100)]
kernel: new mount cache
this is a new more simple version of the mount cache
that does not require dynamic allocations for extends.
the Mntcache structure now contains a page bitmap
that is used for quick page invalidation. the size
of the bitmap is proportional to MAXCACHE.
instead of keeping track of cached range in the
Extend data structure, we keep all the information
in the Page itself. the offset from the page where
the cache range starts is in the low PGSHIT bits and
the end in the top bits of Page.va.
we choose Page.daddr to map 1:1 the Mountcache number
and page number (pn) in the Mountcache. to find a page,
we first check the bitmap if the page is there and then
do a pagelookup() with the daddr key.
cinap_lenrek [Sun, 14 Dec 2014 21:10:34 +0000 (22:10 +0100)]
kernel: get rid of /boot/boot parametrization
there is no use for "bootdisk" variable parametrization
of /boot/boot and no point for the boot section with its
boot methods in the kernel configuration anymore. so
mkboot and boot$CONF.out are gone.
move the rules for bootfs.paq creation in 9/boot/bootmkfile.
location of bootfs.proto is now in 9/boot/bootfs.proto.
our /boot/boot target is now just "boot".
cinap_lenrek [Sat, 13 Dec 2014 23:00:59 +0000 (00:00 +0100)]
kernel: evaluate dependencies of bootfs.proto files for bootfs.paq
expand the list of files specified in bootfs.proto and use them
as dependencies to bootfs.paq rule. this way, bootfs.paq is
regenerated when the to be included files have been modified.
cinap_lenrek [Thu, 11 Dec 2014 19:20:47 +0000 (20:20 +0100)]
acme: fix buffer overrun in xfidutfread() and xfidruneread(), cleanup
the utf8 buffers b1 where allocated from fbufalloc() which gives
us BUFSIZE bytes, but Xfid->count can be bigger than that. so just
emalloc() the requested number of bytes.
when converting from Runes to utf-8, we have to account for the
terminating '\0' byte snprint() places, so fix the maxrune number
calculation instead of using BUFSIZE+1 as buffer size.
A buffer can be overflowed in the init function of kbmap.c by using a filename of more than 112 characters.
sample output:
% cd /sys/lib/kbmap
% touch aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
% kbmap
kbmap 1974: suicide: sys: trap: fault write addr=0xa6a96510 pc=0x000011df
offending code is most likely the call to sprint in the init function of /sys/src/cmd/kbmap.c,
which in this case writes /sys/lib/kbmap/$file to a 128-bit buffer.
I'm willing to submit a patch for this myself along with a few minor improvements/fixes to kbmap
if I can figure out the nuances of doing so.
cinap_lenrek [Tue, 9 Dec 2014 21:26:30 +0000 (22:26 +0100)]
bootrc: do not pass authserver with -a flag to factotum, handle multiple secstore addresses
factotum is started in bootrc before the network is setup
(as we need it to negotiate wpa key for wifi). once, the network
is setup, the bootstrap authservers are passed in /net/ndb,
which factotum reads when doing bootstrap authdial. it does
this only when no authserver was specified earlier! but we
want net.rc to select the proper bootstrap authserver...
the $secstore variable takes precedence over $auth. as
there is no connection server yet, we have to select the set
of servers here and pass them to secstore with -s flag.
note that this will work if multiple addresses where
specified.