for queue like non-seekable files, it is impossible to implement an
exportfs because one has to run the kernels devtab read() and write()
in separate processes, and that makes it impossible to maintain 9p message
order as the scheduler can come in and randomly schedule one process before
another.
so as soon as we have a transition from 9p -> syscalls, we'r screwed.
i currently see just two possibilities:
- introduce special file type like QTSEQ with strictly ordered i/o semantics
- fix all fileservers and exportfs to only do one outstanding i/o to QTSEQ files
which means maintaining a queue per fid
this doesnt propagate. so exporting slow 9p mount again will be limited
again by latency of the inner mount.
other option:
- return offset in Rread, so client can bring responses back into order. this
requires changing all fileservers and drivers to maintain such an per fid offset
and change the protocol to include it in the response, and also pass it to userspace
(new syscalls or pass it in TOS)
this only works for read pipelining, write is still screwed.
both options suck.
--
cinap
(ppp->secret comes from factotum and it can have any size)
This patch also sets the correct state after success and
failure cases in chap negotiation (without them the code was
working because it expected the other point to pass to net
phase or due to the timer).
p2.patch: Do not request encriptation with -c or -C in ppp
(it was a bit annoying request compression, and when the ACK
from the server was received then send a NAK).
p3.patch: Add support for md5 and mschap in in chap
(without this patch ppp was passing to the net stage
without worring about chap).
- remove redundant flushimage() calls before readmouse()
- remove flushimage() calls for allocimage(),freeimage() and originwindow()
this is experimental. it will break allocimage() error handling unless the
caller does explicit flushimage() calls, tho the gains
in usability over high latency connections is huge. in most cases, programs
will just terminate when encountering these errors.
both server and client need to be convinced that the connection
is broken for a connection reestablishment to happen as the server
will only start looking for incoming clients when the connection
already broke. so use the 8 second interval sync messages
to check for connection lifeness. if we miss two syncs in time,
we declare the connecton to be broken and will try to reconnect.
k0ga reports:
Hello,
While I was setting my pppoe conexion with my ISP
I discovered several problems in ip/pppoe. I used
the command line ip/pppoe -A '' ether0 and I got
this:
...
dropping unwanted pkt: wrong ac name
panic: D2B called on non-block dc10 (double-free?)
note rcved: sys: trap: fault read addr=0x0 pc=0x000066e1
pppoe 1013: suicide: sys: trap: fault read addr=0x0 pc=0x000066e1
cpu% acid 1013
/proc/1013/text:386 plan 9 executable
/sys/lib/acid/port
/sys/lib/acid/386
acid: stk()
abort()+0x0 /sys/src/libc/9sys/abort.c:6
ppanic(p=0xd1b8,fmt=0xc7f9)+0x146 /sys/src/libc/port/malloc.c:166
D2B(p=0xd1b8,v=0xdc10)+0x57 /sys/src/libc/port/pool.c:926
poolfreel(v=0xdc10,p=0xd1b8)+0x20 /sys/src/libc/port/pool.c:1152
poolfree(p=0xd1b8,v=0xdc10)+0x3b /sys/src/libc/port/pool.c:1287
free(v=0xdc18)+0x23 /sys/src/libc/port/malloc.c:250
clearstate()+0x1b /sys/src/cmd/ip/pppoe.c:328
pppoe(ether=0xdfffefc1)+0x123 /sys/src/cmd/ip/pppoe.c:426
main(argv=0xdfffefa0,argc=0x1)+0x89 /sys/src/cmd/ip/pppoe.c:100
_main+0x31 /sys/src/libc/386/main9.s:16
acid:
clearstate() is called in pppoe.c:424, and it frees acname and sets it
to nil. pktread() is called in pppoe.c:434 with parameter wantoffer,
which frees acname again in line pppoe.c:360 but doesn't set it to
nil, so clearstate() makes a double free in the next iteration.
this allows running kbdfs under kbdfs :-)
going use this in new drawterm. drawterm provides the initial
/dev/kbd, but only sends rune up/down messages (keeps it simple).
the servers kbdfs reads that and exports itself the full
set of files, similar to what we do in vncs. this also
provides note processing.
the dns file service can be restarted, which causes it to forget
all fid state. given the simple file system structure of the dns
service (just a single dns file), we can assume that rpcs
on a unknown fid refers to the root, so the mountpoint will stay
valid and /net/dns can be reopend avoiding the need for a remount
of the dns service after restart.
The execexec() function should never return, as it irreversably changes
the filedescriptor table for the new program. This means rc's internal
filedesciptors for reading the script get implicitely closed and we cannot
continue the rc interpreter when Execute() fails. So Execute() now sets the
error status, and execexec() runs Xexit() in case Execute() returns.
when we look up role=speakfor key and askforkeys is set, the
findkey() can return RpcNeedkey, which causes us to skip the
query for a role=client key. Instead, we now check for the
return value != RpcOk (and != RpcConfirm which we want to
handle the same for both queries).
we have to free the attribute lists when returning RpcConfirm.
the ini buffer was not reset when we got eof in the message
body read causing a endless loop. instead of defining our
own read9pmsg() function, just handle the first read specially
when we consumed the first 4 bytes for the "impo" protocol
escape check.
When a window is moved or reshaped, that implicitely tops
the window and makes it current. The conseqence of this
is that we always have to redraw the window as if it where
a current window in any case. This was handled for Reshaped
windows, but not when the window was just moved. We now
handle both cases the exact same way, getting rid of the
Moved wctl message.
