Bluetooth: Split triggering of discovery commands into separate function

The actual process of compiling the correct HCI commands for triggering
discovery is something that should be generic. So instead of mixing it
into the Start Discover operation handling, split it out into its own
function utilizing HCI request handling and just providing status in
case of errors or invalid parameters.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
xen/arm: remove handling of XENFEAT_grant_map_identity

The feature has been removed from Xen. Also Linux cannot use it on ARM32
without CONFIG_ARM_LPAE.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
xen/arm: remove outer_*_range call

Dom0 is not actually capable of issuing outer_inv_range or
outer_clean_range calls.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
xen/arm: if(pfn_valid(pfn)) call native dma_ops

Remove code duplication in mm32.c by calling the native dma_ops if the
page is a local page (not a foreign page). Use a simple pfn_valid(pfn)
check to figure out if the page is local, exploiting the fact that dom0
is mapped 1:1, therefore pfn_valid always returns false when called on a
foreign mfn.

Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
arm64: introduce is_device_dma_coherent

Introduce a boolean flag and an accessor function to check whether a
device is dma_coherent. Set the flag from set_arch_dma_coherent_ops.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
arm: introduce is_device_dma_coherent

Introduce a boolean flag and an accessor function to check whether a
device is dma_coherent. Set the flag from set_arch_dma_coherent_ops.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
xen/arm: use is_device_dma_coherent

Use is_device_dma_coherent to check whether we need to issue cache
maintenance operations rather than checking on the existence of a
particular dma_ops function for the device.

This is correct because coherent devices don't need cache maintenance
operations - arm_coherent_dma_ops does not set the hooks that we
were previously checking for existance.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
xen: add a dma_addr_t dev_addr argument to xen_dma_map_page

dev_addr is the machine address of the page.

The new parameter can be used by the ARM and ARM64 implementations of
xen_dma_map_page to find out if the page is a local page (pfn == mfn) or
a foreign page (pfn != mfn).

dev_addr could be retrieved again from the physical address, using
pfn_to_mfn, but it requires accessing an rbtree. Since we already have
the dev_addr in our hands at the call site there is no need to get the
mfn twice.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen/arm: use hypercall to flush caches in map_page

In xen_dma_map_page, if the page is a local page, call the native
map_page dma_ops. If the page is foreign, call __xen_dma_map_page that
issues any required cache maintenane operations via hypercall.

The reason for doing this is that the native dma_ops map_page could
allocate buffers than need to be freed. If the page is foreign we don't
call the native unmap_page dma_ops function, resulting in a memory leak.

Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
xen/arm/arm64: merge xen/mm32.c into xen/mm.c

Merge xen/mm32.c into xen/mm.c.
As a consequence the code gets compiled on arm64 too.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
xen/arm/arm64: introduce xen_arch_need_swiotlb

Introduce an arch specific function to find out whether a particular dma
mapping operation needs to bounce on the swiotlb buffer.

On ARM and ARM64, if the page involved is a foreign page and the device
is not coherent, we need to bounce because at unmap time we cannot
execute any required cache maintenance operations (we don't know how to
find the pfn from the mfn).

No change of behaviour for x86.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen/arm: introduce GNTTABOP_cache_flush

Introduce support for new hypercall GNTTABOP_cache_flush.
Use it to perform cache flashing on pages used for dma when necessary.

If GNTTABOP_cache_flush is supported by the hypervisor, we don't need to
bounce dma map operations that involve foreign grants and non-coherent
devices.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
swiotlb-xen: pass dev_addr to xen_dma_unmap_page and xen_dma_sync_single_for_cpu

xen_dma_unmap_page and xen_dma_sync_single_for_cpu take a dma_addr_t
handle as argument, not a physical address.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org
swiotlb-xen: remove BUG_ON in xen_bus_to_phys

On x86 truncation cannot occur because config XEN depends on X86_64 ||
(X86_32 && X86_PAE).

On ARM truncation can occur without CONFIG_ARM_LPAE, when the dma
operation involves foreign grants. However in that case the physical
address returned by xen_bus_to_phys is actually invalid (there is no mfn
to pfn tracking for foreign grants on ARM) and it is not used.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org
swiotlb-xen: call xen_dma_sync_single_for_device when appropriate

In xen_swiotlb_sync_single we always call xen_dma_sync_single_for_cpu,
even when we should call xen_dma_sync_single_for_device. Fix that.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org
swiotlb-xen: pass dev_addr to swiotlb_tbl_unmap_single

Need to pass the pointer within the swiotlb internal buffer to the
swiotlb library, that in the case of xen_unmap_single is dev_addr, not
paddr.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org
xen/pciback: Don't deadlock when unbinding.

As commit 0a9fd0152929db372ff61b0d6c280fdd34ae8bdb
'xen/pciback: Document the entry points for 'pcistub_put_pci_dev''
explained there are four entry points in this function.
Two of them are when the user fiddles in the SysFS to
unbind a device which might be in use by a guest or not.

Both 'unbind' states will cause a deadlock as the the PCI lock has
already been taken, which then pci_device_reset tries to take.

We can simplify this by requiring that all callers of
pcistub_put_pci_dev MUST hold the device lock. And then
we can just call the lockless version of pci_device_reset.

To make it even simpler we will modify xen_pcibk_release_pci_dev
to quality whether it should take a lock or not - as it ends
up calling xen_pcibk_release_pci_dev and needs to hold the lock.

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
driver core: Provide an wrapper around the mutex to do lockdep warnings

Instead of open-coding it in drivers that want to double check
that their functions are indeed holding the device lock.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Suggested-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
xen/pciback: Include the domain id if removing the device whilst still in use

Cleanup the function a bit - also include the id of the
domain that is using the device.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
xen/pciback: Print out the domain owning the device.

We had been printing it only if the device was built with
debug enabled. But this information is useful in the field
to troubleshoot.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>