the special sencodefmt() in ndb/dn.c is only used with %H format for
hexadecimal printing for binary strings. removing the unused
calls to enc32() and enc64() reduces the code size by arround 4K.
(this is usefull for ndb/getip which gets linked into the kernel).
the approximation of n*2 to calculate the number of output bytes
for enc64() fails for inputs of size < 3. this is fixed by using
encodefmt() which gets the calculation right and also simplifies
the code avoiding the allocation and freeing of intermediate string
buffers.
mcountseg(), mfreeseg():
use Pte.first/last pointers when possible and avoid constructs
like s->map[i]->pages[j].
freepte():
do not zero entries in freepte(), the segment is going away and
here is no point in zeroing page pointers. hoist common code at
the top avoiding duplication.
segpage(), fixfault():
avoid load after store for Pte** pointer.
fixfault():
return -1 in default case to avoid the "used but not set" warning
for mmuphys and get rid of the useless initialization.
syssegflush():
due to len being unsigned, the pe = PGROUND(pe) can make "chunk"
bigger than len causing a overflow. rewrite the function and deal
with page alignment and errors at the beginning.
syssegflush(), segpage(), fixfault(), putseg(), relocateseg(),
mcountseg(), mfreeseg():
keep naming consistent.
the "to" address can overflow in syssegfree() causing wrong
number of pages to be passed to mfreeseg(). with the current
implementation of mfreeseg() however, this doesnt cause any
data corruption but was just freeing an unexpected number of
pages.
this change checks for this condition in syssegfree() and
errors out instead. also mfreeseg() was changed to take
ulong argument for number of pages instead of int to keep
it consistent with other routines that work with page counts.
sdbio() tests if it can pass the buffer pointer directly to
the driver when it is already in kernel memory. we also need
to check if the buffer is properly aligned but alignment
requirement is handled in system specific sdmalloc() and
was not known to devsd.
to solve this, we *always* page align sd buffers and get rid
of the system specific sdmalloc() macro (was only used in bcm
kernel).
chaninit() does not initialize Chan.qentry and Chan.nentry
and there is no way to get rid of such a channel. nobody is
using it, so removing the function to avoid confusion.
ignore physical segments in mcountseg() and mfreeseg(). physical
segments are not backed by user pages, and doing putpage() on
physical segment pages in mfreeseg() is an error.
do now allow physical segemnts to be resized. the segment size
is only checked in segattach() to be within the physical segment!
ignore physical segments in portcountpagerefs() as pagenumber()
does not work on the malloced page structures of a physical segment.
get rid of Physseg.pgalloc() and Physseg.pgfree() indirection as
this was never used and if theres a need to do more efficient
allocation, it should be done in a portable way.
it is possible to have fonts belong to different or no display, so the
check for defaultsubfont has to be against font->display, not the global
display variable.
remove unused freeup() routine.
handle strdup() error in allocsubfont() and realloc() error in buildfont().
the namespace might be shared by other processes. instead, we
create a anonymous pipe with pipe() and use devdup to open one
end close-on-exec. this is shorter and avoids the race condition.
do not touch Execargs after writing the error message as the
process might be gone after the write. this was to manually
close the fd which isnt neccesary as the kernel will do it
for us on the following exit.
