KAMEZAWA Hiroyuki and Oleg Nesterov point out that since the commit
557ed1fa ("remove ZERO_PAGE") removed
the ZERO_PAGE from the VM mappings, any users of get_user_pages() will
generally now populate the VM with real empty pages needlessly.

We used to get the ZERO_PAGE when we did the "handle_mm_fault()", but
since fault handling no longer uses ZERO_PAGE for new anonymous pages,
we now need to handle that special case in follow_page() instead.

In particular, the removal of ZERO_PAGE effectively removed the core
file writing optimization where we would skip writing pages that had not
been populated at all, and increased memory pressure a lot by allocating
all those useless newly zeroed pages.

This reinstates the optimization by making the unmapped PTE case the
same as for a non-existent page table, which already did this correctly.

While at it, this also fixes the XIP case for follow_page(), where the
caller could not differentiate between the case of a page that simply
could not be used (because it had no "struct page" associated with it)
and a page that just wasn't mapped.

We do that by simply returning an error pointer for pages that could not
be turned into a "struct page *".  The error is arbitrarily picked to be
EFAULT, since that was what get_user_pages() already used for the
equivalent IO-mapped page case.

[ Also removed an impossible test for pte_offset_map_lock() failing:
  that's not how that function works ]
Acked-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NNick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When we demote a slice from 64k to 4k, and we are about to insert an
HPTE for a 4k subpage and we notice that there is an existing 64k
HPTE, we first invalidate that HPTE before inserting the new 4k
subpage HPTE.  Since the bits that encode which hash bucket the old
HPTE was in overlap with the bits that encode which of the 16 subpages
have HPTEs, we need to clear out the subpage HPTE-present bits before
starting to insert HPTEs for the 4k subpages.  If we don't do that, we
can erroneously think that a subpage already has an HPTE when it
doesn't.

That in itself wouldn't be such a problem except that when we go to
update the HPTE that we think is present on machines with a
hypervisor, the hypervisor can tell us that the HPTE we think is there
is actually there even though it isn't, which can lead to a process
getting stuck in a loop, continually faulting.  The reason for the
confusion is that the AVPN (abbreviated virtual page number) we are
looking for in the HPTE for a 4k subpage can actually match the AVPN
in a stale HPTE for another 64k page.  For example, the HPTE for
the 4k subpage at 0x84000f000 will be in the same hash bucket and have
the same AVPN as the HPTE for the 64k page at 0x8400f0000.

This fixes the code to clear out the subpage HPTE-present bits.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

A recent commit added support for the new 440x6 and 464 cores that have the
added WL1, IL1I, IL1D, IL2I, and ILD2 bits for the caching attributes in the
TLBs.  The new bits were cleared in the finish_tlb_load function, however a
similar bit of code was missed in the DataStorage interrupt vector.
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This enables CONFIG_ATA_SFF in the defconfigs that are intended to
work on a G5 powermac, i.e. g5_defconfig and ppc64_defconfig.  Since
the support for the SATA cell in the K2 chipset is provided by the
sata_svw.c driver, and that depends on CONFIG_ATA_SFF, we need to turn
that and CONFIG_SATA_SVW back on so we can get to the hard disk on G5s.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

There are no in-tree uses of the export any more and in linux-next there
is a change that exports it globally which causes warnings:

WARNING: vmlinux: 'console_drivers' exported twice. Previous export was in vmlinux

and in one case (mpc85xx_defconfig) a build error:

kernel/built-in.o: In function `__crc_console_drivers':
(*ABS*+0x1eb0e6f5): multiple definition of `__crc_console_drivers'

So remove the export now.  Also, there is no longer any need to include
linux/console.h.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

GCC 4.4.x looks to be adding support for generating out-of-line register
saves/restores based on:

http://gcc.gnu.org/ml/gcc-patches/2008-04/msg01678.html

This breaks the kernel if we enable CONFIG_CC_OPTIMIZE_FOR_SIZE.  To fix
this we add the use the save/restore code from gcc and simplified it down
for our needs (integer only).

Additionally, we have to link this code into each module.  The other
solution was to add EXPORT_SYMBOL() which meant going through the
trampoline which seemed nonsensical for these out-of-line routines.

Finally, we add some checks to prom_init_check.sh to ignore the
out-of-line save/restore functions.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

GCC 4.4.x looks to be adding support for generating out-of-line register
saves/restores based on:

http://gcc.gnu.org/ml/gcc-patches/2008-04/msg01678.html

This breaks the bootwrapper as we'd need to link with libgcc to get the
implementation of the register save/restores.

To workaround this issue, we just stole the save/restore code from gcc
and simplified it down for our needs (integer only).
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Fix this:

/usr/src/devel/arch/powerpc/platforms/pseries/eeh_driver.c: In function 'print_device_node_tree':
/usr/src/devel/arch/powerpc/platforms/pseries/eeh_driver.c:55: warning: ISO C90 forbids mixed declarations and code

also make that function look like it's part of Linux.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

of_node_put is needed before discarding a value received from
of_find_node_by_type, eg in error handling code.

The semantic patch that makes the change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
struct device_node *n;
struct device_node *n1;
struct device_node *n2;
statement S;
identifier f1,f2;
expression E1,E2;
constant C;
@@

n = of_find_node_by_type(...)
...
if (!n) S
... when != of_node_put(n)
    when != n1 = f1(n,...)
    when != E1 = n
    when any
    when strict
(
+ of_node_put(n);
  return -C;
|
  of_node_put(n);
|
  n2 = f2(n,...)
|
  E2 = n
|
  return ...;
)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Acked-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

debugfs_create_file() returns a non-NULL (non-zero) value in case of
success, not a NULL value.

This fixes this non-critical boot-time debugging error message:

[    1.316386] calling  irq_debugfs_init+0x0/0x50
[    1.316399] initcall irq_debugfs_init+0x0/0x50 returned -12 after 0 msecs
[    1.316411] initcall irq_debugfs_init+0x0/0x50 returned with error code -12
Signed-off-by: NEmil Medve <Emilian.Medve@Freescale.com>
Acked-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

There is a delay in the transition to the stopped state for class 2
interrupts. In some cases, the controlling thread detects the state of
the spu as running, and goes back to sleep resulting in a hung
application as the event is missed.

This change detects the stop condition and re-generates the wakeup event
after a context save.
Signed-off-by: NLuke Browning <lukebrowning@us.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>

Time slicing can occur at the same time as spu exception handling
resulting in the wakeup of the wrong thread.

This change uses the the spu's register_lock to enforce synchronization
between bind/unbind and spu exception handling so that they are
mutually exclusive.
Signed-off-by: NLuke Browning <lukebrowning@us.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>

According to the CBEA, the SPU dsisr is not updated for class 0
exceptions.

spu_stopped() is testing the dsisr that was passed to it from the class
0 exception handler, so we return a false positive here.

This patch cleans up the interrupt handler and erroneous tests in
spu_stopped. It also removes the fields from the csa since it is not
needed to process class 0 events.
Signed-off-by: NLuke Browning <lukebrowning@us.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>

If the spu is stopping (ie, the SPU_STATUS_RUNNING bit is still set),
re-read the register to get the final stopped value.
Signed-off-by: NLuke Browning <lukebrowning@us.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>

Without simpleImage% in the BOOT_TARGETS list, it is impossible to
build any of the simpleImages.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

MDIO-less PHYs should use CONFIG_FIXED_PHY driver and appropriate
fixed-link property in the device tree.

If not, ethernet will not work:
  e0024520:03 not found
  eth1: Could not attach to PHY
  IP-Config: Failed to open eth1
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Update the defconfig for the Freescale MPC8610 HPCD board.  Enable module
support.  Disable support for all NICs except for the on-board ULI526x.
Enable support for the Freescale DIU driver.  Increase the maximum zone order
to 12, so that the DIU driver can allocate physically-contiguous 5MB buffers.
Enable SYSV IPC and OSS plugin support, which are needed for some OSS apps.
Signed-off-by: NTimur Tabi <timur@freescale.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Andrew Klossner pointed out the IO space size was in violation of
the alignment requirements for windows on the 85xx.  The size should
have been 1M (to match u-boot).
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

The MPC85xx MDS board requires some board level tweaks of the PHYs that
either the eTSEC (gianfar) or UCC ethernet controllers are connected to.

Its possible to build the phylib as a module, however this breaks the
board level fix ups because phy_read and phy_write are not available
if we build as a module.

So we unconditionally select PHYLIB to ensure its built into the kernel
if we are building in MPC85xx MDS support.  This was determined to be
the easiest soultion even though it prevents the user from removing
PHYLIB support if they decide they don't want it.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

The ehea driver was recently changed[1] to use walk_memory_resource() to
detect the system's memory layout.  However, walk_memory_resource() is
available only when memory hotplug is enabled.  So CONFIG_EHEA was
made to depend on MEMORY_HOTPLUG [2], but it is inappropriate for a
network driver to have such a dependency.

Make the declaration of walk_memory_resource() and its powerpc
implementation (ehea is powerpc-specific) unconditionally available.

[1] 48cfb14f
    "ehea: Add DLPAR memory remove support"

[2] fb7b6ca2
    "ehea: Add dependency to Kconfig"
Signed-off-by: NNathan Lynch <ntl@pobox.com>
Acked-by: NBadari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

During the next merge window, pci_name()'s return value will become
const, so use the new dev_set_name() instead to avoid the warning (from
linux-next):

arch/powerpc/kernel/pci_64.c: In function 'of_create_pci_dev':
arch/powerpc/kernel/pci_64.c:193: warning: passing argument 1 of 'sprintf' discards qualifiers from pointer target type

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

When building a signal or a ucontext, we can incorrectly set the MSR_VEC
bit of the kernel pt_regs->msr before returning to userspace if the task
-ever- used VMX.

This can lead to funny result if that stack used it in the past, then
"lost" it (ie. it wasn't enabled after a context switch for example)
and then called get_context.  It can end up with VMX enabled and the
registers containing values from some other task.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This corrects the names of two CONFIG_ variables.

Note that the CONFIG_MPC86XADS fix uncovers another bug
(with mpc866_ads_defconfig) that will require fixing:

<--  snip  -->

...
arch/powerpc/boot/dtc -O dtb -o arch/powerpc/boot/mpc866ads.dtb -b 0  /home/bunk/linux/kernel-2.6/git/linux-2.6/arch/powerpc/boot/dts/mpc866ads.dts
DTC: dts->dtb  on file "/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/powerpc/boot/dts/mpc866ads.dts"
  WRAP    arch/powerpc/boot/cuImage.mpc866ads
powerpc64-linux-ld: arch/powerpc/boot/cuboot-mpc866ads.o: No such file: No such file or directory
make[2]: *** [arch/powerpc/boot/cuImage.mpc866ads] Error 1

<--  snip  -->
Reported-by: NRobert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Change the name of the device from "rtc-ds1374" to just "ds1374", to match
what all other RTC drivers do.  I seem to remember that this name was
chosen to avoid possible confusion with an older ds1374 driver, but that
driver was removed 3 months ago.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This code shouldn't be hit anyways, but when it is, it's useful to have a
little more information about the failure.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

gfn_to_page() and kvm_release_page_clean() are called from other contexts with
mmap_sem locked only for reading.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

We're not calling kmap() now, so we shouldn't call kunmap() either. This has no
practical effect in the non-highmem case, which is why it hasn't caused more
obvious problems.

Pointed out by Anthony Liguori.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Somehow these load/store instructions got missed before, but weren't used by
the guest so didn't break anything.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NChristian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

This was left behind from some code movement.
Signed-off-by: NHollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The node for DMA2 in the MPC8610 HPCD device tree has the wrong compatible
properties.  This breaks the DMA driver and the sound driver.
Signed-off-by: NTimur Tabi <timur@freescale.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Refresh pasemi_defconfig and enable ELECTRA_CF=y.
Signed-off-by: NOlof Johansson <olof@lixom.net>

Compiling ppc64_defconfig with gcc 4.3 gives thes warnings:

arch/powerpc/sysdev/mpic.c: In function 'mpic_irq_get_priority':
arch/powerpc/sysdev/mpic.c:1351: warning: 'is_ipi' may be used uninitialized in this function
arch/powerpc/sysdev/mpic.c: In function 'mpic_irq_set_priority':
arch/powerpc/sysdev/mpic.c:1328: warning: 'is_ipi' may be used uninitialized in this function

It turns out that in the cases where is_ipi is uninitialized, another
variable (mpic) will be NULL and it is dereferenced.  Protect against
this by returning if mpic is NULL in mpic_irq_set_priority, and removing
mpic_irq_get_priority completely as it has no in tree callers.

This has the nice side effect of making the warning go away.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Since commit "85xx: Add support for relocatable kernel (and
booting at non-zero)" (37dd2bad),
PHYSICAL_START is #defined as kernstart_addr if RELOCATABLE
and FLATMEM is enabled.

PHYSICAL_START is used in prom_init.c and so kernstart_addr
needs to be added to the list of allowed symbols that
prom_init.c can access.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

__set_fixmap() in pgtable_32.c currently fails to compile if
STRICT_MM_TYPECHECKS is defined.  This fixes it.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

A change was made to walk_memory_resource() in commit
4b119e21 that added a
check of find_lmb().  Add the coresponding lmb_add()
call to ps3_mm_add_memory() so that that check will
succeed.

This fixes the condition where the PS3 boots up with
only the 128 MiB of boot memory, and doesn't see the
other 128MiB that is available.
Signed-off-by: NGeoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Signed-off-by: NPaul Mackerras <paulus@samba.org>

Signed-off-by: NKumar Gala <galak@kernel.crashing.org>