The only time when granted pages need to be treated specially is when
using Xen's PTE modification for grant mappings owned by another domain
(that is, only gntdev on PV guests).  Otherwise, the area does not
require VM_DONTCOPY and VM_PFNMAP, since it can be accessed just like
any other page of RAM.

Since the vm_operations_struct close operations decrement reference
counts, a corresponding open function that increments them is required
now that it is possible to have multiple references to a single area.

We are careful in the gntdev to check if we can remove those flags. The
reason that we need to be careful in gntdev on PV guests is because we are
not changing the PFN/MFN mapping on PV; instead, we change the application's
page tables to point to the other domain's memory. This means that the vma
cannot be copied without using another grant mapping hypercall; it also
requires special handling on unmap, which is the reason for gntdev's
dependency on the MMU notifier.

For gntalloc, this is not a concern - the pages are owned by the domain
using the gntalloc device, and can be mapped and unmapped in the same manner
as any other page of memory.
Acked-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v2: Added in git commit "We are.." from email correspondence]

addr is actually a virtual address so use an unsigned long. Fixes:

  CC      drivers/xen/gntdev.o
drivers/xen/gntdev.c: In function 'map_grant_pages':
drivers/xen/gntdev.c:268: warning: cast from pointer to integer of different size

Reduce the scope of the variable at the same time.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The caller will not undo a mapping which failed and therefore the
override will not be removed.

This is especially bad in the case of GNTMAP_contains_pte mapping type
mappings where m2p_add_override will destroy the kernel mapping of the
page.

This was observed via a failure of map_grant_pages in gntdev_mmap (due
to userspace using a bad grant reference), which left the page in
question unmapped (because it was a GNTMAP_contains_pte mapping) which
led to a crash later on.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Cc: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The handle with numeric value 0 is a valid map handle, so it cannot
be used to indicate that a page has not been mapped. Use -1 instead.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

When CONFIG_XEN is enabled the gntdev and gntalloc driver will be
compiled as a module by default.

[v2: Added the fix for the gntalloc driver as well]
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

If an already-mapped area of the device was mapped into userspace a
second time, a hypercall was incorrectly made to remap the memory
again. Avoid the hypercall on later mmap calls, and fail the mmap call
if a writable mapping is attempted on a read-only range.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

In paravirtualized domains, mn_invl_page or mn_invl_range_start can
unmap a segment of a mapped region without unmapping all pages. When
the region is later released, the pages will be unmapped twice, leading
to an incorrect -EINVAL return.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The is_mapped flag used to be set at the completion of the map operation,
but was not checked in all error paths. Use map->vma instead, which will
now be cleared if the initial grant mapping fails.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

In paravirtualized guests, the struct page* for mappings is only a
placeholder, and cannot be used to access the granted memory. Use the
userspace mapping that we have set up in order to implement
UNMAP_NOTIFY_CLEAR_BYTE.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The error path did not decrement the reference count of the grant structure.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This ioctl allows the users of a shared page to be notified when
the other end exits abnormally.

[v2: updated description in structs]
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This allows a userspace application to allocate a shared page for
implementing inter-domain communication or device drivers. These
shared pages can be mapped using the gntdev device or by the kernel
in another domain.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

HVM does not allow direct PTE modification, so instead we request
that Xen change its internal p2m mappings on the allocated pages and
map the memory into userspace normally.

Note:
The HVM path for map and unmap is slightly different: HVM keeps the pages
mapped until the area is deleted, while the PV case (use_ptemod being true)
must unmap them when userspace unmaps the range. In the normal use case,
this makes no difference to users since unmap time is deletion time.

[v2: Expanded commit descr.]
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This allows userspace to perform mmap() on the gntdev device and then
immediately close the filehandle or remove the mapping using the
remove ioctl, with the mapped area remaining valid until unmapped.
This also fixes an infinite loop when a gntdev device is closed
without first unmapping all areas.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This should be faster if many mappings exist, and also removes
the only user of map->vma not related to PTE modification.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Because there is no limitation on how many times a user can open a
given device file, an per-file-description limit on the number of
pages granted offers little to no benefit. Change to a global limit
and remove the ioctl() as the parameter can now be changed via sysfs.

Xen tools changeset 22768:f8d801e5573e is needed to eliminate the
error this change produces in xc_gnttab_set_max_grants.
Signed-off-by: NDaniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

FREQ is a ridiculously short name for a platform-specific macro in a
generic header, and it now conflicts with an enumeration in the
gspca/ov519 driver.

Also delete conditional reference to ixp4xx_get_board_tick_rate()
which is not defined anywhere.
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NKrzysztof Hałasa <khc@pm.waw.pl>

Don't allow everybody to set terminator via sysfs.
Signed-off-by: NVasiliy Kulikov <segoon@openwall.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't allow everybody to write to mb0_id file.
Signed-off-by: NVasiliy Kulikov <segoon@openwall.com>
Acked-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In drm_crtc_helper_set_config, instead of always forcing all outputs
to DRM_MODE_DPMS_ON, only set them if the CRTC is actually getting a
mode set, as any mode set will turn all outputs on.

This fixes https://lkml.org/lkml/2011/1/24/457Signed-off-by: NKeith Packard <keithp@keithp.com>
Cc: stable@kernel.org (2.6.37)
Reported-and-tested-by: NCarlos R. Mafra <crmafra2@gmail.com>
Tested-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

While the RxFIFO interruption is masked for most 8168, nothing prevents
it to appear in the irq status word. This is no excuse to crash.
Signed-off-by: NFrancois Romieu <romieu@fr.zoreil.com>
Cc: Ivan Vecera <ivecera@redhat.com>
Cc: Hayes <hayeswang@realtek.com>

Some experiment-based action to prevent my 8168 chipsets locking-up hard
in the irq handler under load (pktgen ~1Mpps). Apparently a reset is not
always mandatory (is it at all ?).

- RTL_GIGA_MAC_VER_12
- RTL_GIGA_MAC_VER_25
  Missed ~55% packets. Note:
  - this is an old SiS 965L motherboard
  - the 8168 chipset emits (lots of) control frames towards the sender

- RTL_GIGA_MAC_VER_26
  The chipset does not go into a frenzy of mac control pause when it
  crashes yet but it can still be crashed. It needs more work.
Signed-off-by: NFrancois Romieu <romieu@fr.zoreil.com>
Cc: Ivan Vecera <ivecera@redhat.com>
Cc: Hayes <hayeswang@realtek.com>

I found that one of the 8168c chipsets (concretely XID 1c4000c0) starts
generating RxFIFO overflow errors. The result is an infinite loop in
interrupt handler as the RxFIFOOver is handled only for ...MAC_VER_11.
With the workaround everything goes fine.
Signed-off-by: NIvan Vecera <ivecera@redhat.com>
Acked-by: NFrancois Romieu <romieu@fr.zoreil.com>
Cc: Hayes <hayeswang@realtek.com>

The comments under "config STUB_POULSBO" are close to correct,
but they are not being followed.  This patch updates them to reflect
the requirements for THERMAL.

This build error is caused by STUB_POULSBO selecting ACPI_VIDEO
when ACPI_VIDEO's config requirements are not met.

ERROR: "thermal_cooling_device_register" [drivers/acpi/video.ko] undefined!
ERROR: "thermal_cooling_device_unregister" [drivers/acpi/video.ko] undefined!
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Tested-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NDave Airlie <airlied@redhat.com>

As reported by Flavio Leitner, there is no synchronization to protect
NIU's get_stats method from seeing a NULL pointer in either
np->rx_rings or np->tx_rings.  In fact, as far as ->ndo_get_stats
is concerned, these values are set completely asynchronously.

Flavio attempted to fix this using a RW semaphore, which in fact
works most of the time.  However, dev_get_stats() can be invoked
from non-sleepable contexts in some cases, so this fix doesn't
work in all cases.

So instead, control the visibility of the np->{rx,tx}_ring pointers
when the device is being brough up, and use properties of the device
down sequence to our advantage.

In niu_get_stats(), return immediately if netif_running() is false.
The device shutdown sequence first marks the device as not running (by
clearing the __LINK_STATE_START bit), then it performans a
synchronize_rcu() (in dev_deactive_many()), and then finally it
invokes the driver ->ndo_stop() method.

This guarentees that all invocations of niu_get_stats() either see
netif_running() as false, or they see the channel pointers before
->ndo_stop() clears them out.

If netif_running() is true, protect against startup races by loading
the np->{rx,tx}_rings pointer into a local variable, and punting if
it is NULL.  Use ACCESS_ONCE to prevent the compiler from reloading
the pointer on us.

Also, during open, control the order in which the pointers and the
ring counts become visible globally using SMP write memory barriers.
We make sure the np->num_{rx,tx}_rings value is stable and visible
before np->{rx,tx}_rings is.

Such visibility control is not necessary on the niu_free_channels()
side because of the RCU sequencing that happens during device down as
described above.  We are always guarenteed that all niu_get_stats
calls are finished, or will see netif_running() false, by the time
->ndo_stop is invoked.
Reported-by: NFlavio Leitner <fleitner@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We previously used a static array, but some new systems
had more states then we had array space, so dynamically
allocate space based on the number of states in the vbios.

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=33851Signed-off-by: NAlex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>

The accelerate mode bit gets checked by certain atom
command tables to set up some register state.  It needs
to be clear when setting modes and set when not.

Fixes:
https://bugzilla.kernel.org/show_bug.cgi?id=26942Signed-off-by: NAlex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>

Some BIOSs (eg.  the AMI BIOS on the Asus P4P800 motherboard) don't
initialise the GART address, and pcibios_assign_resources() can ignore it
because it can be marked as a host bridge (see
https://bugzilla.kernel.org/show_bug.cgi?id=24392#c5 for details).  This
was handled correctly up to 2.6.35, but the pci_enable_device() cleanup in
2.6.36 96576a9e ("agp: intel-agp: do not use PCI resources before
pci_enable_device()") means that the kernel tries to enable the GART
before assigning it an address; in such cases the GART overlaps with other
device assignments and ends up being disabled.

This patch fixes https://bugzilla.kernel.org/show_bug.cgi?id=24392

Note that I imagine efficeon-agp.c probably has the same problem, but
I can't test that and I'd like to make sure this patch is suitable for
-stable (since 2.6.36 and 2.6.37 are affected).
Signed-off-by: NStephen Kitt <steve@sk2.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Maciej Rutecki <maciej.rutecki@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Kulikov Vasiliy <segooon@gmail.com>
Cc: Florian Mickler <florian@mickler.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This reverts commit f191f144.

The AMD 751 and 761 chipsets are used on the UP1000, UP1100, and UP1500
OEM motherboards, but they neglect to do anything to make AGP work.

According to Ivan Kokshaysky:
There is quite fundamental conflict between the Alpha architecture and
x86 AGP implementation - Alpha is entirely cache coherent by design,
while x86 AGP is not (I mean native AGP DMA transactions, not a PCI over
AGP). There are no such things as non-cacheable mappings or software
support for cache flushing/invalidation on Alpha, so x86 AGP code won't
work on Nautilus.

So there's no point in allowing this driver to be configured on Alpha.
Signed-off-by: NMatt Turner <mattst88@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

amd-k7-agp can't be built on Alpha anymore, so remove now unnecessary
code.
Signed-off-by: NMatt Turner <mattst88@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

These should be handled by the clear_state setup, but set them
directly as well just to be sure.
Signed-off-by: NAlex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>

Adds new packet to disable DX9 constant emulation.
Signed-off-by: NAlex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: NDave Airlie <airlied@redhat.com>

This patch prevents a user space program from calling the RTC_IRQP_SET
ioctl with a negative value of frequency. Also, if this call is make
with a zero value of frequency, there would be a division by zero in the
kernel code.

[jstultz: Also initialize irq_freq to 1 to catch other divbyzero issues]

CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>

Commit 8f574b35 ("atl1c: Add AR8151 v2
support and change L0s/L1 routine") added support for a new adapter
but failed to add it to the PCI device table.
Signed-Off-By: NChuck Ebbert <cebbert@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This error was reported by cppcheck:
drivers/s390/net/smsgiucv.c:63: error: Using sizeof for array given as
function argument returns the size of pointer.

Although there is no runtime problem as long as sizeof(u8 *) == 8,
this misleading code should get fixed.
Signed-off-by: NStefan Weil <weil@mail.berlios.de>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This error was reported by cppcheck:
drivers/s390/net/netiucv.c:568: error: Using sizeof for array given
as function argument returns the size of pointer.

sizeof(ipuser) did not result in 16 (as many programmers would have
expected) but sizeof(u8 *), so it is 4 or 8, too small here.
Signed-off-by: NStefan Weil <weil@mail.berlios.de>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For OSA the CHPARM-definition determines the number of available
outbound queues.
A CHPARM-change may occur while a Linux system with probed
OSA device is in suspend state. This patch enables proper
resuming of an OSA device in this case.
Signed-off-by: NUrsula braun <ursula.braun@de.ibm.com>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For HiperSockets the framesize-definition determines the selected
mtu-size and the size of the allocated qdio buffers.
A framesize-change may occur while a Linux system with probed
HiperSockets device is in suspend state. This patch enables proper
resuming of a HiperSockets device in this case.
Signed-off-by: NUrsula Braun <ursula.braun@de.ibm.com>
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>