Until now, the ptrace syscall was implemented as a wrapper that called
various functions in procfs depending on which ptrace operation was
requested. Most of these functions were themselves wrappers around
procfs_{read,write}_{,db,fp}regs(), with only some extra error checks,
which weren't necessary in the ptrace case anyway.
This commit moves procfs_rwmem() from procfs_mem.c into sys_process.c
(renaming it to proc_rwmem() in the process), and implements ptrace()
directly in terms of procfs_{read,write}_{,db,fp}regs() instead of
having it fake up a struct uio and then call procfs_do{,db,fp}regs().
It also moves the prototypes for procfs_{read,write}_{,db,fp}regs()
and proc_rwmem() from proc.h to ptrace.h, and marks all procfs files
except procfs_machdep.c as "optional procfs" instead of "standard".
Handle overlap in bcopy.
Add routines for copying and zeroing pages using physical addresses
directly.
Remove all the hacks to account for calling the firmware on its own
trap table, we use the kernel trap table. There is still a problem
with OF_exit().
easier and hopefully this code is done changing radically.
Don't use the mmu tlb register to address the kernel page table, nor
the 8k pointer register. The hardware will do some of the page table
lookup by storing the the base address in an internal register and
calculating the address of the tte in the table. However it is limited
to a 1 meg tsb, which only maps 512 megs. The kernel page table only
has one level, so its easy to just do it by hand, which has the advantage
of supporting abitrary amounts of kvm and only costs a few more instructions.
Increase kvm to 1 gig now that its easy to do so and so we don't waste
most of a 4 meg page.
Fix some traces. Fix more proc locking.
Call tsb_stte_promote if we get a soft fault on a mapping in the upper
levels of the tsb. If there is an invalid or unreferenced mapping
in the primary tsb, it will be replaced.
Immediately fail for faults occuring in {f,s}uswintr.
one 4 meg page can map both the kernel and the openfirmware mappings.
Add the openfirmware mappings to the kernel tsb so we can call the firmware
on the kernel trap table and access kernel memory normally.
Implement pmap_swapout_proc, pmap_swapin_proc, pmap_swapout_thread,
pmap_swapin_thread, pmap_activate, pmap_page_exists, and pmap_phys_address.
Add a guard page at the bottom of the kernel stack. Its unclear how easy
it will be to detect these faults and do something useful.
Setup the registers on exec how the c runtime expects.
Implement various {fill,set}_*regs.
Fix proc locking.
will be private to each CPU.
- Re-style(9) the globaldata structures. There really needs to be a MI
struct pcpu that has a MD struct mdpcpu member at some point.
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
it to the MI area. KSE touched cpu_wait() which had the same change
replicated five ways for each platform. Now it can just do it once.
The only MD parts seemed to be dealing with fpu state cleanup and things
like vm86 cleanup on x86. The rest was identical.
XXX: ia64 and powerpc did not have cpu_throw(), so I've put a functional
stub in place.
Reviewed by: jake, tmm, dillon
with user windows in kernel mode. We split the windows using %otherwin,
but instead of spilling user window directly to the pcb, we attempt to
spill to user space. If this fails because a stack page is not resident
(or the stack is smashed), the fault handler at tl 2 will detect the
situation and resume at tl 1 again where recovery code can spill to the
pcb. Any windows that have been saved to the pcb will be copied out to
the user stack on return from kernel mode.
Add a first stab at 32 bit window handling. This uses much of the same
recovery code as above because the alignment of the stack pointer is used
to detect 32 bit code. Attempting to spill a 32 bit window to a 64 bit
stack, or vice versa, will cause an alignment fault. The recovery code
then changes the window state to vector to a 32 bit spill/fill handler
and retries the faulting instruction.
Add ktr traces in useful places during trap processing.
Adjust comments to reflect new code and add many more.
Remove the modified tte bit and add a softwrite bit. Mappings are only
writeable if they have been written to, thus in general modify just
duplicates the write bit. The softwrite bit makes it easier to distinguish
mappings which should be writeable but are not yet modified.
Move the exec bit down one, it was being sign extended when used as an
immediate operand.
Use the lock bit to mean tsb page and remove the tsb bit. These are the
only form of locked (tsb) entries we support and we need to conserve bits
where possible.
Implement pmap_copy_page and pmap_is_modified and friends.
Detect mappings that are being being upgraded from read-only to read-write
due to copy-on-write and update the write bit appropriately.
Make trap_mmu_fault do the right thing for protection faults, which is
necessary to implement copy on write correctly. Also handle a bunch
more userland trap types and add ktr traces.
Instead introduce the [M] prefix to existing keywords. e.g.
MSTD is the MP SAFE version of STD. This is prepatory for a
massive Giant lock pushdown. The old MPSAFE keyword made
syscalls.master too messy.
Begin comments MP-Safe procedures with the comment:
/*
* MPSAFE
*/
This comments means that the procedure may be called without
Giant held (The procedure itself may still need to obtain
Giant temporarily to do its thing).
sv_prepsyscall() is now MP SAFE and assumed to be MP SAFE
sv_transtrap() is now MP SAFE and assumed to be MP SAFE
ktrsyscall() and ktrsysret() are now MP SAFE (Giant Pushdown)
trapsignal() is now MP SAFE (Giant Pushdown)
Places which used to do the if (mtx_owned(&Giant)) mtx_unlock(&Giant)
test in syscall[2]() in */*/trap.c now do not. Instead they
explicitly unlock Giant if they previously obtained it, and then
assert that it is no longer held to catch broken system calls.
Rebuild syscall tables.