as with the Block refcount changes, _xinc() and _xdec() arent
used anymore, so remove them.
architecure can still define ainc()/adec() when it needs them.
change Proc.nlocks from Ref to int and just use normal increment and decrelemt
as done in erik quanstros 9atom.
It is not clear why we used atomic increment in the fist place as even if we
get preempted by interrupt and scheduled before we write back the incremented
value, it shouldnt be a problem and we'll just continue where we left off as
our process is the only one that can write to it.
Yoann Padioleau found that the Mach pointer Lock.m wasnt maintained
consistently for lock() vs canlock() and ilock(). Fixed.
Use uintptr instead of ulong for maxlockpc, maxilockpc and ilockpc debug variables.
webfs forks the namespace to isolate itself from its mount
point which has the side effect that it captures the mount
of previous instances of webfs mounted on /mnt/web.
explicitely unmount the mountpoint in our namespace copy
to drop the reference.
when there are multiple readers of /dev/usbevent, we have to
serialize the processing to make sure that only one driver
is opening the devices control endpoint at a time.
to do this, we assume the device is busy after reading the
event file until the next read or clunk on the same fid.
to mark a device busy, we set the dev->aux pointer to the
fid processing a event. And the Event structure takes a
reference to the device producing the event.
the problem arised from cdc ethernet and nusb/serial sharing
the same device class, and we need to run the particular driver
to figure out if the device can be used. doing this concurrently
fails because devusb allows only one open per endpoint.
the palloc.pages array takes arround 5% of the upages which
gives us:
16GB = ~0.8GB
32GB = ~1.6GB
64GB = ~3.2GB
we only have 2GB of address space above KZERO so this will not
work for long.
instead, pageinit() was altered to accept a preallocated memory
in palloc.pages. and preallocpages() in pc64/main.c allocates the
in upages memory, mapping it in the VMAP area (which has 512GB).
the drawback is that we cannot poke at Page structures now from
/proc/n/mem as the VMAP area is not accessible from it.
Without an explicit signal for a truncation, copy propagation will
sometimes propagate a 32-bit truncation and end up overwriting uses of
the original 64-bit value.
This was independently discovered and fixed in Go. See:
http://golang.org/issue/1315https://codereview.appspot.com/6002043/
Thanks Charles Forsyth for tips and advice.
as we do system reset and reboot only from boot processor cpu0 now,
theres no need for active.rebooting conditional variable.
mpshutdown() will unconditionally park application processors and
and cpu0 boots the new kernel or calls mpshutdown() causing system
reset.
in vmware, mpshutdown() used to hang in i8042reset() when not
called from the boot processor, so instead of reseting from first
cpu that acquires the shutdown lock, we park all application
processors and let the boot processor do the reset.
procwrite() did truncate the offset to 32bit ulong.
introduce off2addr() function that does the sign
extension hack and use it conststently for Qmem
reads and writes.
for the CMclose procctl, the fd number was not
bounds checked before indexing in the Fgrp.fd
array.
for the CMclosefiles, we looped fd from 0..maxfd-1,
but need to loop from 0..maxfd as maxfd is inclusive.
newns() (called by auth_chuid()) already prepares the
environment variables and puts us in a sane working
directory (as specified by the namespace file).
on amd64, the text segment is aligned and padded to
2MB, but segment granularity is 4K which can give
us page faults that are beyond the highest file
offset. this is perfectly valid, but was not handled
correctly in pio().
use two per process memory slots, one for the
pid and one for the fd instead of a global table
avoiding the case when the table gets full.
instead of calling pread() on the cached fd
(dangerous as it has side effects when the
fd was not closed), we check if the cached fd
is still good using fd2path() when called
the first time in this process.
theres big performance regression with this using
cwfs. cwfs calls time() to update atime on every
read/write which now causes walks on /dev.
reverting to the previous version for now. in the
long run, we'll use new _nsec() syscall but this
has to wait for a later release once new kernels
are established.
trackers do like the new default Mozilla/5.0 (compatible)
user agent. so force useragent to hjdicks and give option
to override it in case trackers get even more clever in
the future.
in dhcpwatch, the sleep time "secs" could become
zero potentially freezing the lease time.
give up when in Sinit state in dhcpquery() as this
is a terminal state.
from the specification:
software may reset the entire HBA by setting GHC.HR to '1'.
When software sets the GHC.HR bit to '1', the HBA shall perform
an internal reset action. The bit shall be cleared to '0'
by the HBA when the reset is complete.
sites like google return the wrong characterset when
they do not recognize the user-agent. so setting default
user agent to something thats likely to pass these
idiotic browser tests.
> warning: a.c:9 useless or misleading comparison: UINT < 0
the error can be observed by compiling the following code
with warnings enabled:
#include <u.h>
#include <libc.h>
uint r;
void
main(int argc, char *argv[])
{
int r;
if(r < 0){
exits(0);
}
}
the offending code in the compiler is:
- if(l->op == ONAME && l->sym->type){
- lt = l->sym->type;
- if(lt->etype == TARRAY)
- lt = lt->link;
- }
compiler handles scope by overwritin and reverting
symbols while parsing. in the ccom phase, the nodes symbol
(n->sym) is not in the right scope and we wrongly think r
is uint instead of int.
it is not clear to me what this code tried to accomplish in
the first place nor could anyone answer me this question.
the risk is small as this change doesnt affect the compiled
program, only the warning, so removing the offending code.
the malloc pool allocator is limited in its allocation
size. as almost all data structures in cwfs are never
freed, use brk() in ialloc() instead of mallocalign().
this means memory returned by ialloc() cannot be freed!
to make sure we do not call free by accident, remove
the #define malloc(n) ialloc(n, 0) macro and use ialloc()
directly as in the original code to show the intend
of permanent allocations.
this was a big mistake. we should never attempt to
timeout or retry a scsi command from the controller
driver because theres no way to tell how long a
command would take or if a command has side effects
when being retried.
number of bank slots in Conf.mem[4] was too small
for kenjis machine, set it to maximum 16 (the
size of the RAM map in pc64/memory.c).
also increasing the UPA memory map to 64. the
e820 map on my x200s has 31 entries and many
holes. this gets rid of the "mapfree: ... losing"
messages on boot.
