plan9fox/sys
cinap_lenrek 46070c3122 kernel: add segio() function for reading/writing segments
devproc's procctlmemio() did not handle physical segment
types correctly, as it assumed it can just kmap() the page
in question and write to it. physical segments however
need to be mapped uncached but kmap() will always map
cached as it assumes normal memory. on some machines with
aliasing memory with different cache attributes
leads to undefined behaviour!

we borrow the code from devsegment and provide a generic
segio() function to read and write user segments which
handles all the cases without using kmap by just spawning
a kproc that attaches the segment that needs to be read
from or written to. fault() will setup the right mmu
attributes for us. it will also properly flush pages for
segments that maintain instruction cache when written.
however, tlb's have to be flushed separately.

segio() is used for devsegment and devproc now, which
also allows for simplification of fixfault() as there is no
special error handling case anymore as fixfault() is now
called from faulting process *only*.

reads from /proc/$pid/mem can now span multiple pages.
2015-04-16 00:45:25 +02:00
..
doc
games/lib fortunes: TED, day 1: I want to believe -- WIRED magazine 2015-03-26 20:43:41 -04:00
include libmach: use #pragma pack to force 4 byte alignment of bootexec.h structures for amd64 2015-03-18 19:31:51 +01:00
lib hg: install hgweb templates 2015-03-13 18:30:59 +01:00
man segment(3): document fixed segment creation 2015-04-12 16:38:39 +02:00
src kernel: add segio() function for reading/writing segments 2015-04-16 00:45:25 +02:00