Commit graph

1263 commits

Author SHA1 Message Date
Benjamin Herrenschmidt
faa8bf8878 Merge branch 'booke-hugetlb' into next 2011-12-08 13:20:34 +11:00
Benjamin Herrenschmidt
48b1bf86c3 Merge branch 'mpic' into next 2011-12-07 18:22:47 +11:00
Benjamin Herrenschmidt
4666ca2aa3 powerpc/pci: Make pci_read_irq_line() static
It's only used inside the same file where it's defined. There's
also no point exporting it anymore.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 18:04:58 +11:00
Benjamin Herrenschmidt
f11fe5524a powerpc/powernv: Update OPAL interfaces
This adds some more interfaces for OPAL v2

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 18:02:02 +11:00
Becky Bruce
1f6820b4c1 powerpc: Define/use HUGETLB_NEED_PRELOAD insead of complicated #if
Define HUGETLB_NEED_PRELOAD in mmu-book3e.h for CONFIG_PPC64 instead
of having a much more complicated #if block.  This is easier to read
and maintain.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:24 +11:00
Becky Bruce
d93e4d7d72 powerpc/book3e: Change hugetlb preload to take vma argument
This avoids an extra find_vma() and is less error-prone.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:24 +11:00
Becky Bruce
a6146888be powerpc: Add gpages reservation code for 64-bit FSL BOOKE
For 64-bit FSL_BOOKE implementations, gigantic pages need to be
reserved at boot time by the memblock code based on the command line.
This adds the call that handles the reservation, and fixes some code
comments.

It also removes the previous pr_err when reserve_hugetlb_gpages
is called on a system without hugetlb enabled - the way the code is
structured, the call is unconditional and the resulting error message
spurious and confusing.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:23 +11:00
Becky Bruce
881fde1db5 powerpc: hugetlb: modify include usage for FSL BookE code
The original 32-bit hugetlb implementation used PPC64 vs PPC32 to
determine which code path to take.  However, the final hugetlb
implementation for 64-bit FSL ended up shared with the FSL
32-bit code so the actual check needs to be FSL_BOOK3E vs
everything else.  This patch changes the include protections to
reflect this.

There are also a couple of related comment fixes.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:22 +11:00
Becky Bruce
97632e6fbe powerpc: hugetlb: fix huge_ptep_set_access_flags return value
There was an unconditional return of "1" in the original code
from David Gibson, and I dropped it because it wasn't needed
for FSL BOOKE 32-bit.  However, not all systems (including 64-bit
FSL BOOKE) do loading of the hpte from the fault handler asm
and depend on this function returning 1, which causes a call
to update_mmu_cache() that writes an entry into the tlb.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:21 +11:00
Becky Bruce
7651295944 powerpc: Only define HAVE_ARCH_HUGETLB_UNMAPPED_AREA if PPC_MM_SLICES
If we don't have slices, we should be able to use the generic
hugetlb_get_unmapped_area() code

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 16:26:21 +11:00
Kyle Moffett
c51242e708 powerpc/mpic: Cache the device-tree node in "struct mpic"
Store the node pointer in the MPIC during initialization so that all of
the later operational code can just reuse the cached pointer.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:08 +11:00
Kyle Moffett
be8bec56df powerpc/mpic: Invert the meaning of MPIC_PRIMARY
It turns out that there are only 2 in-tree platforms which use MPICs
which are not "primary":  IBM Cell and PowerMac.  To reduce the
complexity of the typical board setup code, invert the MPIC_PRIMARY bit
into MPIC_SECONDARY.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:08 +11:00
Kyle Moffett
e7a98675ca powerpc/mpic: Save computed phys_addr for board-specific code
The MPIC code can already perform an automatic OF address translation
step as part of mpic_alloc(), but several boards need to use that base
address when they perform mpic_assign_isu().

The easiest solution is to save the computed physical address into the
"struct mpic" for later use by the board code.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-12-07 13:43:07 +11:00
sukadev@linux.vnet.ibm.com
1d54cf2b97 powerpc: Implement CONFIG_STRICT_DEVMEM
As described in the help text in the patch, this token restricts general
access to /dev/mem as a way of increasing the security. Specifically, access
to exclusive IOMEM and kernel RAM is denied unless CONFIG_STRICT_DEVMEM is
set to 'n'.

Implement the 'devmem_is_allowed()' interface for Powerpc. It will be
called from range_is_allowed() when userpsace attempts to access /dev/mem.

This patch is based on an earlier patch from Steve Best and with input from
Paul Mackerras and Scott Wood.

[BenH] Fixed a typo or two and removed the generic change which should
       be submitted as a separate patch

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-28 11:42:08 +11:00
Benjamin Herrenschmidt
56368797d6 Merge remote-tracking branch 'kumar/next' into next 2011-11-25 15:25:39 +11:00
Benjamin Herrenschmidt
184cd4a3b9 powerpc/powernv: PCI support for p7IOC under OPAL v2
This adds support for p7IOC (and possibly other IODA v1 IO Hubs)
using OPAL v2 interfaces.

We completely take over resource assignment and assign them using an
algorithm that hands out device BARs in a way that makes them fit in
individual segments of the M32 window of the bridge, which enables us
to assign individual PEs to devices and functions.

The current implementation gives out a PE per functions on PCIe, and a
PE for the entire bridge for PCIe to PCI-X bridges.

This can be adjusted / fine tuned later.

We also setup DMA resources (32-bit only for now) and MSIs (both 32-bit
and 64-bit MSI are supported).

The DMA allocation tries to divide the available 256M segments of the
32-bit DMA address space "fairly" among PEs. This is done using a
"weight" heuristic which assigns less value to things like OHCI USB
controllers than, for example SCSI RAID controllers. This algorithm
will probably want some fine tuning for specific devices or device
types.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-25 14:53:15 +11:00
Benjamin Herrenschmidt
1f1616e864 powerpc/powernv: Add TCE SW invalidation support
This is used for newer IO Hubs such as p7IOC.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-25 14:32:57 +11:00
Benjamin Herrenschmidt
491b98c315 powerpc/pci: Add a platform hook after probe and before resource survey
Some platforms need to perform resource allocation using a custom algorithm
due to HW constraints, or may want to tweak things globally below a host
bridge. For example OPAL support for IODA will need to perform a
resource allocation pass that applies IODA specific segmentation
constraints to MMIO which cannot be done simply using the kernel generic
resource management code.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-25 14:32:53 +11:00
Geoff Thorpe
09c188c4f6 powerpc: Add pgprot_cached_noncoherent()
This adds a pgprot combination required by some cache-enabled IO device
mappings, such as Freescale datapath (QMan and BMan) portals.

Signed-off-by: Geoff Thorpe <geoff@geoffthorpe.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-25 14:32:52 +11:00
Ravi K. Nittala
df17f56d8a powerpc/pseries: Cancel RTAS event scan before firmware flash
The RTAS firmware flash update is conducted using an RTAS call that is
serialized by lock_rtas() which uses spin_lock. While the flash is in
progress, rtasd performs scan for any RTAS events that are generated by
the system. rtasd keeps scanning for the RTAS events generated on the
machine. This is performed via workqueue mechanism. The rtas_event_scan()
also uses an RTAS call to scan the events, eventually trying to acquire
the spin_lock before issuing the request.

The flash update takes a while to complete and during this time, any other
RTAS call has to wait. In this case, rtas_event_scan() waits for a long time
on the spin_lock resulting in a soft lockup.

Fix: Just before the flash update is performed, the queued rtas_event_scan()
work item is cancelled from the work queue so that there is no other RTAS
call issued while the flash is in progress. After the flash completes, the
system reboots and the rtas_event_scan() is rescheduled.

Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com>
Signed-off-by: Ravi Nittala <ravi.nittala@in.ibm.com>
Reported-by: Divya Vikas <divya.vikas@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-25 14:11:29 +11:00
Jimi Xenidis
fac26ad4f9 powerpc/book3e: Add ICSWX/ACOP support to Book3e cores like A2
ICSWX is also used by the A2 processor to access coprocessors,
although not all "chips" that contain A2s have coprocessors.

Signed-off-by: Jimi Xenidis <jimix@pobox.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-25 14:11:28 +11:00
Milton Miller
8d3d589a79 powerpc/pseries: Software invalidatation of TCEs
Some pseries IOMMUs cache TCEs but don't snoop when the TCEs are changed
in memory, hence we need manually invalidate in software.

This adds code to do the invalidate.  It keys off a device tree property
to say where the to do the MMIO for the invalidate and some information
on what the format of the invalidate including some magic routing info.

it_busno get overloaded with this magic routing info and it_index with
the MMIO address for the invalidate command.

This then gets hooked into the building and freeing of TCEs.

This is only useful on bare metal pseries.  pHyp takes care of this when
virtualised.

Based on patch from Milton with cleanups from Mikey.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-25 14:11:26 +11:00
Anton Blanchard
7df1027542 powerpc/time: Optimise decrementer_check_overflow
decrementer_check_overflow is called from arch_local_irq_restore so
we want to make it as light weight as possible. As such, turn
decrementer_check_overflow into an inline function.

To avoid a circular mess of includes, separate out the two components
of struct decrementer_clock and keep the struct clock_event_device
part local to time.c.

The fast path improves from:

arch_local_irq_restore
     0:       mflr    r0
     4:       std     r0,16(r1)
     8:       stdu    r1,-112(r1)
     c:       stb     r3,578(r13)
    10:       cmpdi   cr7,r3,0
    14:       beq-    cr7,24 <.arch_local_irq_restore+0x24>
...
    24:       addi    r1,r1,112
    28:       ld      r0,16(r1)
    2c:       mtlr    r0
    30:       blr

to:

arch_local_irq_restore
    0:       std     r30,-16(r1)
    4:       ld      r30,0(r2)
    8:       stb     r3,578(r13)
    c:       cmpdi   cr7,r3,0
   10:       beq-    cr7,6c <.arch_local_irq_restore+0x6c>
...
   6c:       ld      r30,-16(r1)
   70:       blr

Unfortunately we still setup a local TOC (due to -mminimal-toc). Yet
another sign we should be moving to -mcmodel=medium.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-25 14:11:26 +11:00
Anton Blanchard
37fb9a0231 powerpc/time: Handle wrapping of decrementer
When re-enabling interrupts we have code to handle edge sensitive
decrementers by resetting the decrementer to 1 whenever it is negative.
If interrupts were disabled long enough that the decrementer wrapped to
positive we do nothing. This means interrupts can be delayed for a long
time until it finally goes negative again.

While we hope interrupts are never be disabled long enough for the
decrementer to go positive, we have a very good test team that can
drive any kernel into the ground. The softlockup data we get back
from these fails could be seconds in the future, completely missing
the cause of the lockup.

We already keep track of the timebase of the next event so use that
to work out if we should trigger a decrementer exception.

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-25 14:09:58 +11:00
Jia Hongtao
09cef8bd07 powerpc/85xx: Add lbc suspend support for PM
Power supply for LBC registers is off when system go to deep-sleep state.
We save the values of registers before suspend and restore to registers
after resume.

We removed the last two reservation arrays from struct fsl_lbc_regs for
allocating less memory and minimizing the memcpy size.

Signed-off-by: Jiang Yutang <b14898@freescale.com>
Signed-off-by: Jia Hongtao <B38951@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-11-24 02:01:40 -06:00
Linus Torvalds
a4cc3889f7 Merge branch 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM guest: prevent tracing recursion with kvmclock
  Revert "KVM: PPC: Add support for explicit HIOR setting"
  KVM: VMX: Check for automatic switch msr table overflow
  KVM: VMX: Add support for guest/host-only profiling
  KVM: VMX: add support for switching of PERF_GLOBAL_CTRL
  KVM: s390: announce SYNC_MMU
  KVM: s390: Fix tprot locking
  KVM: s390: handle SIGP sense running intercepts
  KVM: s390: Fix RUNNING flag misinterpretation
2011-11-20 14:57:43 -08:00
Alexander Graf
bb75c627fb Revert "KVM: PPC: Add support for explicit HIOR setting"
This reverts commit a15bd354f0.

It exceeded the padding on the SREGS struct, rendering the ABI
backwards-incompatible.

Conflicts:

	arch/powerpc/kvm/powerpc.c
	include/linux/kvm.h

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-11-17 16:30:25 +02:00
Benjamin Herrenschmidt
b97021f855 powerpc: Fix atomic_xxx_return barrier semantics
The Documentation/memory-barriers.txt document requires that atomic
operations that return a value act as a memory barrier both before
and after the actual atomic operation.

Our current implementation doesn't guarantee this. More specifically,
while a load following the isync can not be issued before stwcx. has
completed, that completion doesn't architecturally means that the
result of stwcx. is visible to other processors (or any previous stores
for that matter) (typically, the other processors L1 caches can still
hold the old value).

This has caused an actual crash in RCU torture testing on Power 7

This fixes it by changing those atomic ops to use new macros instead
of RELEASE/ACQUIRE barriers, called ATOMIC_ENTRY and ATMOIC_EXIT barriers,
which are then defined respectively to lwsync and sync.

I haven't had a chance to measure the performance impact (or rather
what I measured with kernel compiles is in the noise, I yet have to
find a more precise benchmark)

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-11-17 16:26:07 +11:00
Kumar Gala
187b9f2aa7 powerpc/book3e-64: Fix debug support for userspace
With the introduction of CONFIG_PPC_ADV_DEBUG_REGS user space debug is
broken on Book-E 64-bit parts that support delayed debug events.  When
switch_booke_debug_regs() sets DBCR0 we'll start getting debug events as
MSR_DE is also set and we aren't able to handle debug events from kernel
space.

We can remove the hack that always enables MSR_DE and loads up DBCR0 and
just utilize switch_booke_debug_regs() to get user space debug working
again.

We still need to handle critical/debug exception stacks & proper
save/restore of state for those exception levles to support debug events
from kernel space like we have on 32-bit.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-17 16:26:07 +11:00
Anton Blanchard
d715e433b7 powerpc: Copy down exception vectors after feature fixups
kdump fails because we try to execute an HV only instruction. Feature
fixups are being applied after we copy the exception vectors down to 0
so they miss out on any updates.

We have always had this issue but it only became critical in v3.0
when we added CFAR support (breaks POWER5) and v3.1 when we added
POWERNV (breaks everyone).

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> [v3.0+]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-16 14:47:54 +11:00
Geoff Levand
9fce85f7ff powerpc/ps3: Fix lv1_gpu_attribute hcall
The lv1_gpu_attribute hcall takes three, not five input
arguments.  Adjust the lv1 hcall table and all calls.

Signed-off-by: Geoff Levand <geoff@infradead.org>
CC: Takashi Iwai <tiwai@suse.de>
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-08 14:51:59 +11:00
Yong Zhang
a3a9f3b47d powerpc/irq: Remove IRQF_DISABLED
Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled
and we even check and yell when an interrupt handler
returns with interrupts enabled (see commit [b738a50a:
genirq: Warn when handler enables interrupts]).

So now this flag is a NOOP and can be removed.

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-11-08 14:51:46 +11:00
Linus Torvalds
32aaeffbd4 Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
  Revert "tracing: Include module.h in define_trace.h"
  irq: don't put module.h into irq.h for tracking irqgen modules.
  bluetooth: macroize two small inlines to avoid module.h
  ip_vs.h: fix implicit use of module_get/module_put from module.h
  nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
  include: replace linux/module.h with "struct module" wherever possible
  include: convert various register fcns to macros to avoid include chaining
  crypto.h: remove unused crypto_tfm_alg_modname() inline
  uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
  pm_runtime.h: explicitly requires notifier.h
  linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
  miscdevice.h: fix up implicit use of lists and types
  stop_machine.h: fix implicit use of smp.h for smp_processor_id
  of: fix implicit use of errno.h in include/linux/of.h
  of_platform.h: delete needless include <linux/module.h>
  acpi: remove module.h include from platform/aclinux.h
  miscdevice.h: delete unnecessary inclusion of module.h
  device_cgroup.h: delete needless include <linux/module.h>
  net: sch_generic remove redundant use of <linux/module.h>
  net: inet_timewait_sock doesnt need <linux/module.h>
  ...

Fix up trivial conflicts (other header files, and  removal of the ab3550 mfd driver) in
 - drivers/media/dvb/frontends/dibx000_common.c
 - drivers/media/video/{mt9m111.c,ov6650.c}
 - drivers/mfd/ab3550-core.c
 - include/linux/dmaengine.h
2011-11-06 19:44:47 -08:00
Linus Torvalds
1197ab2942 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (106 commits)
  powerpc/p3060qds: Add support for P3060QDS board
  powerpc/83xx: Add shutdown request support to MCU handling on MPC8349 MITX
  powerpc/85xx: Make kexec to interate over online cpus
  powerpc/fsl_booke: Fix comment in head_fsl_booke.S
  powerpc/85xx: issue 15 EOI after core reset for FSL CoreNet devices
  powerpc/8xxx: Fix interrupt handling in MPC8xxx GPIO driver
  powerpc/85xx: Add 'fsl,pq3-gpio' compatiable for GPIO driver
  powerpc/86xx: Correct Gianfar support for GE boards
  powerpc/cpm: Clear muram before it is in use.
  drivers/virt: add ioctl for 32-bit compat on 64-bit to fsl-hv-manager
  powerpc/fsl_msi: add support for "msi-address-64" property
  powerpc/85xx: Setup secondary cores PIR with hard SMP id
  powerpc/fsl-booke: Fix settlbcam for 64-bit
  powerpc/85xx: Adding DCSR node to dtsi device trees
  powerpc/85xx: clean up FPGA device tree nodes for Freecsale QorIQ boards
  powerpc/85xx: fix PHYS_64BIT selection for P1022DS
  powerpc/fsl-booke: Fix setup_initial_memory_limit to not blindly map
  powerpc: respect mem= setting for early memory limit setup
  powerpc: Update corenet64_smp_defconfig
  powerpc: Update mpc85xx/corenet 32-bit defconfigs
  ...

Fix up trivial conflicts in:
 - arch/powerpc/configs/40x/hcu4_defconfig
	removed stale file, edited elsewhere
 - arch/powerpc/include/asm/udbg.h, arch/powerpc/kernel/udbg.c:
	added opal and gelic drivers vs added ePAPR driver
 - drivers/tty/serial/8250.c
	moved UPIO_TSI to powerpc vs removed UPIO_DWAPB support
2011-11-06 17:12:03 -08:00
Christopher Yeoh
fcf634098c Cross Memory Attach
The basic idea behind cross memory attach is to allow MPI programs doing
intra-node communication to do a single copy of the message rather than a
double copy of the message via shared memory.

The following patch attempts to achieve this by allowing a destination
process, given an address and size from a source process, to copy memory
directly from the source process into its own address space via a system
call.  There is also a symmetrical ability to copy from the current
process's address space into a destination process's address space.

- Use of /proc/pid/mem has been considered, but there are issues with
  using it:
  - Does not allow for specifying iovecs for both src and dest, assuming
    preadv or pwritev was implemented either the area read from or
  written to would need to be contiguous.
  - Currently mem_read allows only processes who are currently
  ptrace'ing the target and are still able to ptrace the target to read
  from the target. This check could possibly be moved to the open call,
  but its not clear exactly what race this restriction is stopping
  (reason  appears to have been lost)
  - Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix
  domain socket is a bit ugly from a userspace point of view,
  especially when you may have hundreds if not (eventually) thousands
  of processes  that all need to do this with each other
  - Doesn't allow for some future use of the interface we would like to
  consider adding in the future (see below)
  - Interestingly reading from /proc/pid/mem currently actually
  involves two copies! (But this could be fixed pretty easily)

As mentioned previously use of vmsplice instead was considered, but has
problems.  Since you need the reader and writer working co-operatively if
the pipe is not drained then you block.  Which requires some wrapping to
do non blocking on the send side or polling on the receive.  In all to all
communication it requires ordering otherwise you can deadlock.  And in the
example of many MPI tasks writing to one MPI task vmsplice serialises the
copying.

There are some cases of MPI collectives where even a single copy interface
does not get us the performance gain we could.  For example in an
MPI_Reduce rather than copy the data from the source we would like to
instead use it directly in a mathops (say the reduce is doing a sum) as
this would save us doing a copy.  We don't need to keep a copy of the data
from the source.  I haven't implemented this, but I think this interface
could in the future do all this through the use of the flags - eg could
specify the math operation and type and the kernel rather than just
copying the data would apply the specified operation between the source
and destination and store it in the destination.

Although we don't have a "second user" of the interface (though I've had
some nibbles from people who may be interested in using it for intra
process messaging which is not MPI).  This interface is something which
hardware vendors are already doing for their custom drivers to implement
fast local communication.  And so in addition to this being useful for
OpenMPI it would mean the driver maintainers don't have to fix things up
when the mm changes.

There was some discussion about how much faster a true zero copy would
go. Here's a link back to the email with some testing I did on that:

http://marc.info/?l=linux-mm&m=130105930902915&w=2

There is a basic man page for the proposed interface here:

http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt

This has been implemented for x86 and powerpc, other architecture should
mainly (I think) just need to add syscall numbers for the process_vm_readv
and process_vm_writev. There are 32 bit compatibility versions for
64-bit kernels.

For arch maintainers there are some simple tests to be able to quickly
verify that the syscalls are working correctly here:

http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgz

Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: <linux-man@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-10-31 17:30:44 -07:00
Paul Gortmaker
e415372acc powerpc: fix implicit use of mutex.h by include/asm/spu.h
We've been getting the header implicitly via module.h in the past
but when we clean that up, we'll get this failure:

  CC      arch/powerpc/platforms/cell/beat_spu_priv1.o
In file included from arch/powerpc/platforms/cell/beat_spu_priv1.c:22:
arch/powerpc/include/asm/spu.h:190: error: field 'list_mutex' has incomplete type
make[2]: *** [arch/powerpc/platforms/cell/beat_spu_priv1.o] Error 1

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:42 -04:00
Paul Gortmaker
9308794884 powerpc: include export.h for files using EXPORT_SYMBOL/THIS_MODULE
Fix failures in powerpc associated with the previously allowed
implicit module.h presence that now lead to things like this:

arch/powerpc/mm/mmu_context_hash32.c:76:1: error: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
arch/powerpc/mm/tlb_hash32.c:48:1: error: type defaults to 'int' in declaration of 'EXPORT_SYMBOL'
arch/powerpc/kernel/pci_32.c:51:1: error: type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL'
arch/powerpc/kernel/iomap.c:36:1: error: type defaults to 'int' in declaration of 'EXPORT_SYMBOL'
arch/powerpc/platforms/44x/canyonlands.c:126:1: error: type defaults to 'int' in declaration of 'EXPORT_SYMBOL'
arch/powerpc/kvm/44x.c:168:59: error: 'THIS_MODULE' undeclared (first use in this function)

[with several contibutions from Stephen Rothwell <sfr@canb.auug.org.au>]

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:38 -04:00
Paul Gortmaker
66b15db69c powerpc: add export.h to files making use of EXPORT_SYMBOL
With module.h being implicitly everywhere via device.h, the absence
of explicitly including something for EXPORT_SYMBOL went unnoticed.
Since we are heading to fix things up and clean module.h from the
device.h file, we need to explicitly include these files now.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:37 -04:00
Linus Torvalds
1bc87b0055 Merge branch 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (75 commits)
  KVM: SVM: Keep intercepting task switching with NPT enabled
  KVM: s390: implement sigp external call
  KVM: s390: fix register setting
  KVM: s390: fix return value of kvm_arch_init_vm
  KVM: s390: check cpu_id prior to using it
  KVM: emulate lapic tsc deadline timer for guest
  x86: TSC deadline definitions
  KVM: Fix simultaneous NMIs
  KVM: x86 emulator: convert push %sreg/pop %sreg to direct decode
  KVM: x86 emulator: switch lds/les/lss/lfs/lgs to direct decode
  KVM: x86 emulator: streamline decode of segment registers
  KVM: x86 emulator: simplify OpMem64 decode
  KVM: x86 emulator: switch src decode to decode_operand()
  KVM: x86 emulator: qualify OpReg inhibit_byte_regs hack
  KVM: x86 emulator: switch OpImmUByte decode to decode_imm()
  KVM: x86 emulator: free up some flag bits near src, dst
  KVM: x86 emulator: switch src2 to generic decode_operand()
  KVM: x86 emulator: expand decode flags to 64 bits
  KVM: x86 emulator: split dst decode to a generic decode_operand()
  KVM: x86 emulator: move memop, memopp into emulation context
  ...
2011-10-30 15:36:45 -07:00
Linus Torvalds
f362f98e7c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue: (21 commits)
  leases: fix write-open/read-lease race
  nfs: drop unnecessary locking in llseek
  ext4: replace cut'n'pasted llseek code with generic_file_llseek_size
  vfs: add generic_file_llseek_size
  vfs: do (nearly) lockless generic_file_llseek
  direct-io: merge direct_io_walker into __blockdev_direct_IO
  direct-io: inline the complete submission path
  direct-io: separate map_bh from dio
  direct-io: use a slab cache for struct dio
  direct-io: rearrange fields in dio/dio_submit to avoid holes
  direct-io: fix a wrong comment
  direct-io: separate fields only used in the submission path from struct dio
  vfs: fix spinning prevention in prune_icache_sb
  vfs: add a comment to inode_permission()
  vfs: pass all mask flags check_acl and posix_acl_permission
  vfs: add hex format for MAY_* flag values
  vfs: indicate that the permission functions take all the MAY_* flags
  compat: sync compat_stats with statfs.
  vfs: add "device" tag to /proc/self/mountstats
  cleanup: vfs: small comment fix for block_invalidatepage
  ...

Fix up trivial conflict in fs/gfs2/file.c (llseek changes)
2011-10-28 10:49:34 -07:00
Eric W. Biederman
1448c721e4 compat: sync compat_stats with statfs.
This was found by inspection while tracking a similar
bug in compat_statfs64, that has been fixed in mainline
since decemeber.

- This fixes a bug where not all of the f_spare fields
  were cleared on mips and s390.
- Add the f_flags field to struct compat_statfs
- Copy f_flags to userspace in case someone cares.
- Use __clear_user to copy the f_spare field to userspace
  to ensure that all of the elements of f_spare are cleared.
  On some architectures f_spare is has 5 ints and on some
  architectures f_spare only has 4 ints.  Which makes
  the previous technique of clearing each int individually
  broken.

I don't expect anyone actually uses the old statfs system
call anymore but if they do let them benefit from having
the compat and the native version working the same.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-10-28 14:58:53 +02:00
Linus Torvalds
efb8d21b2c Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (79 commits)
  TTY: serial_core: Fix crash if DCD drop during suspend
  tty/serial: atmel_serial: bootconsole removed from auto-enumerates
  Revert "TTY: call tty_driver_lookup_tty unconditionally"
  tty/serial: atmel_serial: add device tree support
  tty/serial: atmel_serial: auto-enumerate ports
  tty/serial: atmel_serial: whitespace and braces modifications
  tty/serial: atmel_serial: change platform_data variable name
  tty/serial: RS485 bindings for device tree
  TTY: call tty_driver_lookup_tty unconditionally
  TTY: pty, release tty in all ptmx_open fail paths
  TTY: make tty_add_file non-failing
  TTY: drop driver reference in tty_open fail path
  8250_pci: Fix kernel panic when pch_uart is disabled
  h8300: drivers/serial/Kconfig was moved
  parport_pc: release IO region properly if unsupported ITE887x card is found
  tty: Support compat_ioctl get/set termios_locked
  hvc_console: display printk messages on console.
  TTY: snyclinkmp: forever loop in tx_load_dma_buffer()
  tty/n_gsm: avoid fifo overflow in gsm_dlci_data_output
  tty/n_gsm: fix a bug in gsm_dlci_data_output (adaption = 2 case)
  ...

Fix up Conflicts in:
 - drivers/tty/serial/8250_pci.c
	Trivial conflict with removed duplicate device ID
 - drivers/tty/serial/atmel_serial.c
	Annoying silly conflict between "specify the port num via
	platform_data" and other changes to atmel_console_init
2011-10-26 15:11:09 +02:00
Kumar Gala
37caf9f2a1 powerpc/fsl-booke: Handle L1 D-cache parity error correctly on e500mc
If the L1 D-Cache is in write shadow mode the HW will auto-recover the
error.  However we might still log the error and cause a machine check
(if L1CSR0[CPE] - Cache error checking enable).  We should only treat
the non-write shadow case as non-recoverable.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2011-10-06 23:36:55 -05:00
Paul Bolle
395cf9691d doc: fix broken references
There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.

Fix these broken references, sometimes by dropping the irrelevant text
they were part of.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-27 18:08:04 +02:00
Paul Mackerras
19ccb76a19 KVM: PPC: Implement H_CEDE hcall for book3s_hv in real-mode code
With a KVM guest operating in SMT4 mode (i.e. 4 hardware threads per
core), whenever a CPU goes idle, we have to pull all the other
hardware threads in the core out of the guest, because the H_CEDE
hcall is handled in the kernel.  This is inefficient.

This adds code to book3s_hv_rmhandlers.S to handle the H_CEDE hcall
in real mode.  When a guest vcpu does an H_CEDE hcall, we now only
exit to the kernel if all the other vcpus in the same core are also
idle.  Otherwise we mark this vcpu as napping, save state that could
be lost in nap mode (mainly GPRs and FPRs), and execute the nap
instruction.  When the thread wakes up, because of a decrementer or
external interrupt, we come back in at kvm_start_guest (from the
system reset interrupt vector), find the `napping' flag set in the
paca, and go to the resume path.

This has some other ramifications.  First, when starting a core, we
now start all the threads, both those that are immediately runnable and
those that are idle.  This is so that we don't have to pull all the
threads out of the guest when an idle thread gets a decrementer interrupt
and wants to start running.  In fact the idle threads will all start
with the H_CEDE hcall returning; being idle they will just do another
H_CEDE immediately and go to nap mode.

This required some changes to kvmppc_run_core() and kvmppc_run_vcpu().
These functions have been restructured to make them simpler and clearer.
We introduce a level of indirection in the wait queue that gets woken
when external and decrementer interrupts get generated for a vcpu, so
that we can have the 4 vcpus in a vcore using the same wait queue.
We need this because the 4 vcpus are being handled by one thread.

Secondly, when we need to exit from the guest to the kernel, we now
have to generate an IPI for any napping threads, because an HDEC
interrupt doesn't wake up a napping thread.

Thirdly, we now need to be able to handle virtual external interrupts
and decrementer interrupts becoming pending while a thread is napping,
and deliver those interrupts to the guest when the thread wakes.
This is done in kvmppc_cede_reentry, just before fast_guest_return.

Finally, since we are not using the generic kvm_vcpu_block for book3s_hv,
and hence not calling kvm_arch_vcpu_runnable, we can remove the #ifdef
from kvm_arch_vcpu_runnable.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25 19:52:30 +03:00
Paul Mackerras
0214394760 KVM: PPC: book3s_pr: Simplify transitions between virtual and real mode
This simplifies the way that the book3s_pr makes the transition to
real mode when entering the guest.  We now call kvmppc_entry_trampoline
(renamed from kvmppc_rmcall) in the base kernel using a normal function
call instead of doing an indirect call through a pointer in the vcpu.
If kvm is a module, the module loader takes care of generating a
trampoline as it does for other calls to functions outside the module.

kvmppc_entry_trampoline then disables interrupts and jumps to
kvmppc_handler_trampoline_enter in real mode using an rfi[d].
That then uses the link register as the address to return to
(potentially in module space) when the guest exits.

This also simplifies the way that we call the Linux interrupt handler
when we exit the guest due to an external, decrementer or performance
monitor interrupt.  Instead of turning on the MMU, then deciding that
we need to call the Linux handler and turning the MMU back off again,
we now go straight to the handler at the point where we would turn the
MMU on.  The handler will then return to the virtual-mode code
(potentially in the module).

Along the way, this moves the setting and clearing of the HID5 DCBZ32
bit into real-mode interrupts-off code, and also makes sure that
we clear the MSR[RI] bit before loading values into SRR0/1.

The net result is that we no longer need any code addresses to be
stored in vcpu->arch.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25 19:52:29 +03:00
Alexander Graf
af8f38b349 KVM: PPC: Add sanity checking to vcpu_run
There are multiple features in PowerPC KVM that can now be enabled
depending on the user's wishes. Some of the combinations don't make
sense or don't work though.

So this patch adds a way to check if the executing environment would
actually be able to run the guest properly. It also adds sanity
checks if PVR is set (should always be true given the current code
flow), if PAPR is only used with book3s_64 where it works and that
HV KVM is only used in PAPR mode.

Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25 19:52:27 +03:00
Alexander Graf
0254f07429 KVM: PPC: Add PAPR hypercall code for PR mode
When running a PAPR guest, we need to handle a few hypercalls in kernel space,
most prominently the page table invalidation (to sync the shadows).

So this patch adds handling for a few PAPR hypercalls to PR mode KVM. I tried
to share the code with HV mode, but it ended up being a lot easier this way
around, as the two differ too much in those details.

Signed-off-by: Alexander Graf <agraf@suse.de>

---

v1 -> v2:

  - whitespace fix
2011-09-25 19:52:24 +03:00
Alexander Graf
a15bd354f0 KVM: PPC: Add support for explicit HIOR setting
Until now, we always set HIOR based on the PVR, but this is just wrong.
Instead, we should be setting HIOR explicitly, so user space can decide
what the initial HIOR value is - just like on real hardware.

We keep the old PVR based way around for backwards compatibility, but
once user space uses the SREGS based method, we drop the PVR logic.

Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25 19:52:23 +03:00
Alexander Graf
9432ba6015 KVM: PPC: Add papr_enabled flag
When running a PAPR guest, some things change. The privilege level drops
from hypervisor to supervisor, SDR1 gets treated differently and we interpret
hypercalls. For bisectability sake, add the flag now, but only enable it when
all the support code is there.

Signed-off-by: Alexander Graf <agraf@suse.de>
2011-09-25 19:52:19 +03:00