independent code. Move this code into mincore(), and eliminate the
page queues lock from pmap_mincore().
Push down the page queues lock into pmap_clear_modify(),
pmap_clear_reference(), and pmap_is_modified(). Assert that these
functions are never passed an unmanaged page.
Eliminate an inaccurate comment from powerpc/powerpc/mmu_if.m:
Contrary to what the comment says, pmap_mincore() is not simply an
optimization. Without a complete pmap_mincore() implementation,
mincore() cannot return either MINCORE_MODIFIED or MINCORE_REFERENCED
because only the pmap can provide this information.
Eliminate the page queues lock from vfs_setdirty_locked_object(),
vm_pageout_clean(), vm_object_page_collect_flush(), and
vm_object_page_clean(). Generally speaking, these are all accesses
to the page's dirty field, which are synchronized by the containing
vm object's lock.
Reduce the scope of the page queues lock in vm_object_madvise() and
vm_page_dontneed().
Reviewed by: kib (an earlier version)
Extend struct sysvec with three new elements:
sv_fetch_syscall_args - the method to fetch syscall arguments from
usermode into struct syscall_args. The structure is machine-depended
(this might be reconsidered after all architectures are converted).
sv_set_syscall_retval - the method to set a return value for usermode
from the syscall. It is a generalization of
cpu_set_syscall_retval(9) to allow ABIs to override the way to set a
return value.
sv_syscallnames - the table of syscall names.
Use sv_set_syscall_retval in kern_sigsuspend() instead of hardcoding
the call to cpu_set_syscall_retval().
The new functions syscallenter(9) and syscallret(9) are provided that
use sv_*syscall* pointers and contain the common repeated code from
the syscall() implementations for the architecture-specific syscall
trap handlers.
Syscallenter() fetches arguments, calls syscall implementation from
ABI sysent table, and set up return frame. The end of syscall
bookkeeping is done by syscallret().
Take advantage of single place for MI syscall handling code and
implement ptrace_lwpinfo pl_flags PL_FLAG_SCE, PL_FLAG_SCX and
PL_FLAG_EXEC. The SCE and SCX flags notify the debugger that the
thread is stopped at syscall entry or return point respectively. The
EXEC flag augments SCX and notifies debugger that the process address
space was changed by one of exec(2)-family syscalls.
The i386, amd64, sparc64, sun4v, powerpc and ia64 syscall()s are
changed to use syscallenter()/syscallret(). MIPS and arm are not
converted and use the mostly unchanged syscall() implementation.
Reviewed by: jhb, marcel, marius, nwhitehorn, stas
Tested by: marcel (ia64), marius (sparc64), nwhitehorn (powerpc),
stas (mips)
MFC after: 1 month
where running ofwdump could cause hangs by forcing all secondary CPUs
into a busy wait with interrupts off during the call.
Following section 8.4 of the Open Firmware PowerPC processor binding,
the firmware is free to overwrite the system interrupt handlers during
OF calls, restoring the OS handlers on exit. On single CPU systems, this
process is invisible to the operating system. On multiple CPU systems,
taking any exception on a secondary CPU while an OF call is in progress
ends with that exception vectored into OF, resulting in a slow movement
of the entire system into firmware context and a machine hang.
MFC after: 3 days
here, make the style of assertion used by pmap_enter() consistent
across all architectures.
On entry to pmap_remove_write(), assert that the page is neither
unmanaged nor fictitious, since we cannot remove write access to
either kind of page.
With the push down of the page queues lock, pmap_remove_write() cannot
condition its behavior on the state of the PG_WRITEABLE flag if the
page is busy. Assert that the object containing the page is locked.
This allows us to know that the page will neither become busy nor will
PG_WRITEABLE be set on it while pmap_remove_write() is running.
Correct a long-standing bug in vm_page_cowsetup(). We cannot possibly
do copy-on-write-based zero-copy transmit on unmanaged or fictitious
pages, so don't even try. Previously, the call to pmap_remove_write()
would have failed silently.
firmware in order to take over control of the SMU. Without doing this,
the firmware background process doing fan control will run amok as we
take over the system and crash the management chip.
This is limited to these two machines because our kernel is heavily
dependent on firmware accesses, and so quiescing firmware can cause
nasty problems.
Powermac G5 systems. MSI and several other things are not presently
supported.
The U3/U4 internal device support portions of this change were contributed
by Andreas Tobler.
MFC after: 1 week
vm_page_try_to_free(). Consequently, push down the page queues lock into
pmap_enter_quick(), pmap_page_wired_mapped(), pmap_remove_all(), and
pmap_remove_write().
Push down the page queues lock into Xen's pmap_page_is_mapped(). (I
overlooked the Xen pmap in r207702.)
Switch to a per-processor counter for the total number of pages cached.
Clearing a page table entry's accessed bit and setting the page's
PG_REFERENCED flag in pmap_protect() can't really be justified, so
don't do it.
Additionally, two changes that make this pmap behave like the others do:
Change pmap_protect() such that it calls vm_page_dirty() only if the
page is managed.
Change pmap_remove_write() such that it doesn't clear a page table
entry's accessed bit.
architecture from page queue lock to a hashed array of page locks
(based on a patch by Jeff Roberson), I've implemented page lock
support in the MI code and have only moved vm_page's hold_count
out from under page queue mutex to page lock. This changes
pmap_extract_and_hold on all pmaps.
Supported by: Bitgravity Inc.
Discussed with: alc, jeffr, and kib
pmap_ts_referenced() is not always appropriate for checking whether or
not pages have been referenced because it clears any reference bits
that it encounters. For example, in mincore(), clearing the reference
bits has two negative consequences. First, it throws off the activity
count calculations performed by the page daemon. Specifically, a page
on which mincore() has called pmap_ts_referenced() looks less active
to the page daemon than it should. Consequently, the page could be
deactivated prematurely by the page daemon. Arguably, this problem
could be fixed by having mincore() duplicate the activity count
calculation on the page. However, there is a second problem for which
that is not a solution. In order to clear a reference on a 4KB page,
it may be necessary to demote a 2/4MB page mapping. Thus, a mincore()
by one process can have the side effect of demoting a superpage
mapping within another process!
set to sane values as they no longer default to 0, otherwise some OFW
implementation might copy in or out arguments not based on what the actual
function takes but what ever stack garbage nargs and nreturns supply.
Reviewed by: nwhitehorn
idea in principle, X does not work without them on basically any hardware,
and this is probably the most frequent problem people run into on PowerPC.
Prodded by: rnoland
MFC after: 1 week
to the image_params struct instead of several members of that struct
individually. This makes it easier to expand its arguments in the future
without touching all platforms.
Reviewed by: jhb
has all 4 implemented, but across the processors we now support all the
combinations. For example, the MPC8533 doesn't have a PCI controller
at 0xA0000, but does at 0xB0000.
sure the caches remain coherent. For single-core configurations and
with busdma changes we could eventually switch to "nap" and force
a D-cache invalidation as part of the DMA completion. To this end,
clear PSL_WE until after we handled the decrementer or external
interrupt as it tells us whether we just woke up or not.
in Open Firmware was Apple-specific, and we have complete coverage of Apple
system controllers, so move RTC responsibilities into the system controller
drivers. This avoids interesting problems from manipulating these devices
through Open Firmware behind the backs of their drivers.
Obtained from: NetBSD
MFC after: 2 weeks
generally protected by the VM page queue mutex. Instead of extending the
table lock to cover the PVO heads, add some asserts that the page queue
mutex is in fact held. This fixes several LORs and possible deadlocks.
This also adds an optimization to moea64_kextract() useful for
direct-mapped quantities, like UMA buffers. Being able to use this from
inside UMA removes an additional LOR.
access, and reflects this by autonomously writing LPTE_M into PTE entries.
As such, we should not panic if LPTE_M changes by itself. While here,
fix a harmless typo in moea64_sync_icache().
COMPAT_43TTY enables the sgtty interface. Even though its exposure has
only been removed in FreeBSD 8.0, it wasn't used by anything in the base
system in FreeBSD 5.x (possibly even 4.x?). On those releases, if your
ports/packages are less than two years old, they will prefer termios
over sgtty.
counting in incrementing the interrupt nesting level. This fixes a number
of bugs in which the interrupt thread could be preempted by an IPI,
indefinitely delaying acknowledgement of the interrupt to the PIC, causing
interrupt starvation and hangs.
Reported by: linimon
Reviewed by: marcel, jhb
MFC after: 1 week
the scratchpage is updated, the PVO's physical address is updated as well.
This makes pmap_extract() begin returning non-zero values again, causing
the panic partially fixed in r204297. Fix this by excluding addresses
beyond virtual_end from consideration as KVA addresses, instead of allowing
addresses up to VM_MAX_KERNEL_ADDRESS.
its PVO to map physical address 0 instead of kernelstart. This fixes a
situation in which a user process could attempt to return this address
via KVM, have it fault while being modified, and then panic the kernel
because (a) it is supposed to map a valid address and (b) it lies in the
no-fault region between VM_MIN_KERNEL_ADDRESS and virtual_avail.
While here, move msgbuf and dpcpu make into regular KVA space for
consistency with other implementations.
physical address is changed, there is a brief window during which its PTE
is invalid. Since moea64_set_scratchpage_pa() does not and cannot hold
the page table lock, it was possible for another CPU to insert a new PTE
into the scratch page's PTEG slot during this interval, corrupting both
mappings.
Solve this by creating a new flag, LPTE_LOCKED, such that
moea64_pte_insert will avoid claiming locked PTEG slots even if they
are invalid. This change also incorporates some additional paranoia
added to solve things I thought might be this bug.
Reported by: linimon
such that a fancier thermal management algorithm can be run from user
space, but the kernel will at least ensure your machine does not either
sound like a wind tunnel or catch fire.