the child inherits the stack pointer from the parent (traditional
behavior). Like the signal stack, the stack area is secified as
a low address and a size; machine-dependent code accounts for stack
direction.
This is required for clone(2).
_splraise, _spllower, _splset, _splget, _setsoftintr, _clrsoftintr, _splnone.
They manipulate MIPS processor's 8 interrupt sources and are used
as building blocks for NetBSD spl(9) kernel interface. Note that
MIPS processor doesn't enforce inclusive 'interrupt levels' found
in other processors, then the hierarchal nature of IPL must be
implemented by composing MIPS processor interrupt masks appropriately.
With the simplest target port in which small number of devices are
independently assigned with 6 external interrupt signal lines,
spl(9) kernel interface will be implemented with #define's of
processor interrupt controls mentioned above. In more general
cases, in which target computers have many devices and 'system
registers' indicating pending interrupt sources at any moment,
spl(9) will be implemented with more complex machinary manipulating
processor interrupts and system registers in target port dependent
ways.
- Nuke unused code and reorder locore definitions. XXX Following
routines will be replaced with C language version; setrunqueue,
remrunqueue, switchfpregs, savefpregs, MachFPInterrupt.
- ALIAS() is not needed, use XLEAF() or XNESTED() instead
- use AENT() instead of .aent
- _END_LABEL() is not needed (and was wrong)
- define ALEAF(), NLEAF(), NON_LEAF(), NNON_LEAF() by
XLEAF(), LEAF_NONPROFILE(), NESTED(), NESTED_NONPROFILE()
* Map the message buffer with access_type = VM_PROT_READ|VM_PROT_WRITE `just
because'.
* Map the file system buffers with access_type = VM_PROT_READ|VM_PROT_WRITE to
avoid possible problems with pagemove().
* Do not use VM_PROT_EXEC with either of the above.
* Map pages for /dev/mem with access_type = prot. Also, DO NOT use
pmap_kenter() for this, as we DO NOT want to lose modification information.
* Map pages in dumpsys() with VM_PROT_READ.
* Map pages in m68k mappedcopyin()/mappedcopyout() and writeback() with
access_type = prot.
* For now, bus_dma*(), pmap_map(), vmapbuf(), and similar functions still use
access_type = 0. This should probably be revisited.
allocated from a pool, and the MIPS and Alpha use KSEG to map pool
pages. So, mb_map wasn't actually being used. Saves around 4MB of
kernel virtual address space in a typical configuration.
Garbage-collect the related VM_MBUF_SIZE constant.
pointer to just underneath _start. Allows bootblocks (or other kernel
calling programs) to pass more than 4 arguments if it sets up the stack
properly.
The 4kB figure may be overkill - on the pmax it only needs to be a dozen
of so bytes.
tlbmod exception panics. This appears to have been incorrect even in the pica
pmap.c, which I pulled in for the pmax. Fixes Xcfbpmax crashes on R40x0
systems with sfb framebuffer.
Fix resident_count tracking so it doesn't go negative. UVM will change a
page mapping without removing the original mapping. That was causing a
problem early on when getting UVM working on the mips, and the explicit
pmap_remove() done by pmap_enter() was decrementing the resident_count.
Do the pmap_remove() first, then check if the current mapping is not valid
and increment the resident_count.
the *initial* stack pointer. The proc0 stack is being used by proc0 (i.e.
uvm_scheduler). This had been working because switch_exit() wasn't
overwriting any critical areas of the stack - unless kernel profiling
was turned on.
nisimura