kernel: export mntattach() from devmnt.c avoiding bogus struct passing and special case in namec()
we already export mntauth() and mntversion(), so why not stop
being sneaky and just export mntattach() so bindmount() and
devshr can just call it directly with proper arguments being
checked.
we can also avoid handling #M attach specially in namec()
by having the devmnt's attach function do error(Enoattach).
kernel: clunk the cache when removing cache flag on a channel, only call cread() chen CCACHE flag is set
to avoid double caching, attachimage() and setswapchan() clear
the CCACHE flag on the channel but this keeps the read ahread
state of the cache arround (until the chan gets closed), so also
call cclunk() to detach the mcp and free the read ahead state.
avoid the call to cread() when CCACHE flag is clear.
devmnt: use c->iounit instead of msize-IOHDRSZ to chunk reads and writes, reduce memory overhead for Mntrpc, mntalloc lock
use the actual iounit returned from Ropen/Rcreate to chunk reads and writes
instead of c->mux->msize-IOHDRSZ.
dont preallocate the rpc buffers to msize, most 9p requests are rather small
(except Twrite of course). so we allocate the buffer on demand in mountio()
with some rounding to avoid frequent reallocations.
avoid malloc()/free() while holding mntalloc lock.
this changes devmnt adding mntrahread() function and some helpers
for it to do pipelined sequential read ahead for the mount cache.
basically, cread() calls mntrahread() with Mntrah structure and it
figures out if we where reading sequentially and if thats the case
issues reads of c->iounit size in advance.
the read ahead state (Mntrah) is kept in the mount cache so we can
handle (read ahead) cache invalidation in the presence of writes.
ip/httpfile: fix flushes, fix concurrent reads, set error string
Tflush handling was wrong, we cannot respond to the old
request if we have not actually removed the req from the
in progress block queue.
when reads are issued concurrently, we have to set b->len
before the block is inserted into the inprogress list.
otherwise findblock() is unable to find it and no requests
can be queued on the block. this caused the same offset
to be downloaded multiple times.
set the errstr in getrange() so in case of an error, we dont
get some random previous error string.
as the Fgrp can be shared with other processes, we have to
recheck the fd index after locking the Fgrp in fdclose()
to make sure not to read beyond the bounds of the fd array.
devmnt: do not use user buffer to update the mount cache
using the user buffer has a race where the user can modify
the buffer from another process before it is copied into the cache.
this allows poisoning the cache for every file where the user
has read access.
*after* writing, the directory tree gets alphabetically sorted for
path table. this causes data to not be in the same order as it was
written causing seeks when taring up the filesystem.
so instead write the files in alphabetical order as well to better
match the directory sorting.
9660srv: keep data and metadata separate in the cache with a tag
data on the disk is layed out sequentially and directory information
is at the end of the disk. we want to keep data and metadata separated
so that reading large sequential files will not evict the directory
information from the cache causing long seeks.
for that, we tag the clusters (an 8th for metadata, and the rest
for data) and getbuf() will only evict clusters of the same tag.
cpp: search source file directory first for quoted #include (thanks Ori_B)
foo.c includes bar/bar.h, which includes "baz.h"; it wants bar/baz.h
meanwhile, it also includes meh/quux.h, which includes "baz.h"; it wants meh/baz.h
kernel: reject bogus two byte "#!" shell scripts in sysexec()
- reject files smaller or equal to two bytes, they are bogus
- fix out of bounds access in shargs() when n <= 2
- only copy the bytes read into line buffer
- use nil for pointers instead of 0
kernel: various cleanups of imagereclaim(), pagereclaim(), freepages(), putimage()
imagereclaim(), pagereclaim():
- move imagereclaim() and pagereclaim() declarations to portfns.h
- consistently use ulong type for page counts
- name number of pages to free "pages" instead of "min"
- check for pages == 0 on entry
cinap_lenrek [Sun, 21 Jun 2015 17:35:08 +0000 (19:35 +0200)]
wifi: berlin prime bunny hopping
- reduce delay for channel hop to 200ms
- use 1000ms timeout for auth response (dont hop channels while we wait)
- bunny hop sequence is mathematically prooven
cinap_lenrek [Thu, 18 Jun 2015 10:15:33 +0000 (12:15 +0200)]
kernel: ignore memory pages with singular kernel addresses
addresses va's of 0 and -BY2PG cause trouble with some memmove()/memset()
implementations and possibly other code because of the nil pointer
and end pointers wrapping to zero.
cinap_lenrek [Thu, 18 Jun 2015 02:35:46 +0000 (04:35 +0200)]
zynq: fix barriers
unlock()/iunlock():
we need to place the coherence() *before* "l->key = 0", so that any
stores that where done while holding the lock become observable
*before* other processors see the lock released.
cas()/tas():
place memory barrier before successfull return to prevent reordering.
cinap_lenrek [Thu, 18 Jun 2015 01:13:50 +0000 (03:13 +0200)]
kernel: do not inherit Proc.dot (current working directory) in kproc()
making sure to close the dot in every kproc appears repetitive,
so instead stop inheriting the dot in kproc() as this is usually
never what you wanted in the first place.
cinap_lenrek [Mon, 15 Jun 2015 14:05:00 +0000 (16:05 +0200)]
kernel: implement separate wait queues for page allocation
give kernel processes and local disk file servers (procs
having noswap flag set) a clear advantage for page allocation
under starved condition by giving them ther own wait queue so
they get readied as soon as pages become available.
cinap_lenrek [Mon, 15 Jun 2015 06:28:10 +0000 (08:28 +0200)]
hjfs: defer parent directory permission check for wstat
check parent directory permission *after* we determined
that the new name does not exist in the parent, so that
when the new name is the same as old name then no write
permission is required in the parent directory.
cinap_lenrek [Sun, 14 Jun 2015 19:31:44 +0000 (21:31 +0200)]
ndb/dns: cleanup forwarding code (redistrib())
instead of copying the whole packet, just save the
udp header and restore it aftwards. dont call redistrib()
when there are no forwards (this should be almost always
the case).