Currently allocations are very constrained for 32-bit processes.
It grows down-up from 0x70000000 to 0xf0000000 which gives about
2GB of stack + dynamic mmap() space.
So support the top-down method, and we need to override the
generic helper function in order to deal with D-cache coloring.
With these changes I was able to squeeze out a mmap() just over
3.6GB in size in a 32-bit process.
Signed-off-by: David S. Miller <davem@davemloft.net>
Niagara helps us find a ancient bug in the sparc64 port :-)
The ASI_* values are plain constant defines, thus signed 32-bit
on sparc64. To put shift this into the regs->tstate value we were
doing or'ing "(ASI_PNF << 24)" into there.
ASI_PNF is 0x82 and shifted left by 24 makes that topmost bit the
sign bit in a 32-bit value. This would get sign extended to 64-bits
and thus corrupt the top-half of the reg->tstate value.
This never caused problems in pre-Niagara cpus because the only thing
up there were the condition code values. But Niagara has the global
register level field, and this all 1's value is illegal there so
Niagara gives an illegal instruction trap due to this bug.
I'm pretty sure this bug is about as old as the sparc64 port itself.
This also points out that we weren't setting ASI_PNF for 32-bit tasks.
We should, so fix that while we're here.
Signed-off-by: David S. Miller <davem@davemloft.net>
We now use the TSB hardware assist features of the UltraSPARC
MMUs.
SMP is currently knowingly broken, we need to find another place
to store the per-cpu base pointers. We hid them away in the TSB
base register, and that obviously will not work any more :-)
Another known broken case is non-8KB base page size.
Also noticed that flush_tlb_all() is not referenced anywhere, only
the internal __flush_tlb_all() (local cpu only) is used by the
sparc64 port, so we can get rid of flush_tlb_all().
The kernel gets it's own 8KB TSB (swapper_tsb) and each address space
gets it's own private 8K TSB. Later we can add code to dynamically
increase the size of per-process TSB as the RSS grows. An 8KB TSB is
good enough for up to about a 4MB RSS, after which the TSB starts to
incur many capacity and conflict misses.
We even accumulate OBP translations into the kernel TSB.
Another area for refinement is large page size support. We could use
a secondary address space TSB to handle those.
Signed-off-by: David S. Miller <davem@davemloft.net>
Removed sparc64 architecture specific users of asm/segment.h and
asm-sparc64/segment.h itself
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The implementation is optimal for UltraSPARC-III and later.
It will work, however suboptimally, on UltraSPARC-II and
be treated as a NOP on UltraSPARC-I.
It is not worth code patching this thing as the highest cost
is the code space, and code patching cannot eliminate that.
Signed-off-by: David S. Miller <davem@davemloft.net>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
David Woodhouse