Normally a bitmap from the iommu_table is used to track what TCE entry
is in use. Since we are going to use iommu_table without its locks and
do xchg() instead, it becomes essential not to put bits which are not
implied in the direction flag as the old TCE value (more precisely -
the permission bits) will be used to decide whether to put the page or not.
This adds iommu_direction_to_tce_perm() (its counterpart is there already)
and uses it for powernv's pnv_tce_build().
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This moves page pinning (get_user_pages_fast()/put_page()) code out of
the platform IOMMU code and puts it to VFIO IOMMU driver where it belongs
to as the platform code does not deal with page pinning.
This makes iommu_take_ownership()/iommu_release_ownership() deal with
the IOMMU table bitmap only.
This removes page unpinning from iommu_take_ownership() as the actual
TCE table might contain garbage and doing put_page() on it is undefined
behaviour.
Besides the last part, the rest of the patch is mechanical.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The set_iommu_table_base_and_group() name suggests that the function
sets table base and add a device to an IOMMU group.
The actual purpose for table base setting is to put some reference
into a device so later iommu_add_device() can get the IOMMU group
reference and the device to the group.
At the moment a group cannot be explicitly passed to iommu_add_device()
as we want it to work from the bus notifier, we can fix it later and
remove confusing calls of set_iommu_table_base().
This replaces set_iommu_table_base_and_group() with a couple of
set_iommu_table_base() + iommu_add_device() which makes reading the code
easier.
This adds few comments why set_iommu_table_base() and iommu_add_device()
are called where they are called.
For IODA1/2, this essentially removes iommu_add_device() call from
the pnv_pci_ioda_dma_dev_setup() as it will always fail at this particular
place:
- for physical PE, the device is already attached by iommu_add_device()
in pnv_pci_ioda_setup_dma_pe();
- for virtual PE, the sysfs entries are not ready to create all symlinks
so actual adding is happening in tce_iommu_bus_notifier.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Merge Richard's work to support SR-IOV on PowerNV. All generic PCI
patches acked by Bjorn.
Some minor conflicts with Daniel's pci_controller_ops work.
Conflicts:
arch/powerpc/include/asm/machdep.h
arch/powerpc/platforms/powernv/pci-ioda.c
If a pci_controller_ops struct is provided to iommu_init_early_dart,
populate that with the DMA setup ops, rather than ppc_md. If NULL is
provided, populate ppc_md as before.
This also patches the call sites for Maple and Power Mac to pass
NULL, so existing behaviour is preserved.
The benefit of making this optional is that it means we don't have
to change dart, Maple and Power Mac over to the controller_ops
system in one fell swoop.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Previously the iommu_table had the same lifetime as a struct pnv_ioda_pe
and was embedded in it. The pnv_ioda_pe was assigned to a PE on the bootup
stage. Since PEs are based on the hardware layout which is static in the
system, they will never get released. This means the iommu_table in the
pnv_ioda_pe will never get released either.
This no longer works for VF PE. VF PEs are created and released dynamically
when VFs are created and released. So we need to assign pnv_ioda_pe to VF
PEs respectively when VFs are enabled and clean up those resources for VF
PE when VFs are disabled. And iommu_table is one of the resources we need
to handle dynamically.
Current iommu_table is a static field in pnv_ioda_pe, which will face a
problem when freeing it. During the disabling of a VF,
pnv_pci_ioda2_release_dma_pe will call iommu_free_table to release the
iommu_table for this PE. A static iommu_table will fail in
iommu_free_table.
According to these requirement, this patch allocates iommu_table
dynamically.
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
After d905c5df9a ("PPC: POWERNV: move iommu_add_device earlier"), the
refcnt on the kobject backing the IOMMU group for a PCI device is
elevated by each call to pci_dma_dev_setup_pSeriesLP() (via
set_iommu_table_base_and_group). When we go to dlpar a multi-function
PCI device out:
iommu_reconfig_notifier ->
iommu_free_table ->
iommu_group_put
BUG_ON(tbl->it_group)
We trip this BUG_ON, because there are still references on the table, so
it is not freed. Fix this by moving the powernv bus notifier to common
code and calling it for both powernv and pseries.
Fixes: d905c5df9a ("PPC: POWERNV: move iommu_add_device earlier")
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Tested-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The IOMMU-API gained support for a new iommu_map_sg
function. This causes compile failures on powerpc because
the function name is already globally used there.
This patch renames adds a ppc_ prefix to these functions to
solve the compile problem.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This patch adds the support for to create a direct iommu "bypass"
window on IODA2 bridges (such as Power8) allowing to bypass iommu
page translation completely for 64-bit DMA capable devices, thus
significantly improving DMA performances.
Additionally, this adds a hook to the struct iommu_table so that
the IOMMU API / VFIO can disable the bypass when external ownership
is requested, since in that case, the device will be used by an
environment such as userspace or a KVM guest which must not be
allowed to bypass translations.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch updates the generic iommu backend code to use the
it_page_shift field to determine the iommu page size instead of
using hardcoded values.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds a it_page_shift field to struct iommu_table and
initiliases it to 4K for all platforms.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The powerpc iommu uses a hardcoded page size of 4K. This patch changes
the name of the IOMMU_PAGE_* macros to reflect the hardcoded values. A
future patch will use the existing names to support dynamic page
sizes.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current implementation of IOMMU on sPAPR does not use iommu_ops
and therefore does not call IOMMU API's bus_set_iommu() which
1) sets iommu_ops for a bus
2) registers a bus notifier
Instead, PCI devices are added to IOMMU groups from
subsys_initcall_sync(tce_iommu_init) which does basically the same
thing without using iommu_ops callbacks.
However Freescale PAMU driver (https://lkml.org/lkml/2013/7/1/158)
implements iommu_ops and when tce_iommu_init is called, every PCI device
is already added to some group so there is a conflict.
This patch does 2 things:
1. removes the loop in which PCI devices were added to groups and
adds explicit iommu_add_device() calls to add devices as soon as they get
the iommu_table pointer assigned to them.
2. moves a bus notifier to powernv code in order to avoid conflict with
the notifier from Freescale driver.
iommu_add_device() and iommu_del_device() are public now.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pci_iommu_init() and pci_direct_iommu_init() are not referenced anywhere,
so remove them.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This initializes IOMMU groups based on the IOMMU configuration
discovered during the PCI scan on POWERNV (POWER non virtualized)
platform. The IOMMU groups are to be used later by the VFIO driver,
which is used for PCI pass through.
It also implements an API for mapping/unmapping pages for
guest PCI drivers and providing DMA window properties.
This API is going to be used later by QEMU-VFIO to handle
h_put_tce hypercalls from the KVM guest.
The iommu_put_tce_user_mode() does only a single page mapping
as an API for adding many mappings at once is going to be
added later.
Although this driver has been tested only on the POWERNV
platform, it should work on any platform which supports
TCE tables. As h_put_tce hypercall is received by the host
kernel and processed by the QEMU (what involves calling
the host kernel again), performance is not the best -
circa 220MB/s on 10Gb ethernet network.
To enable VFIO on POWER, enable SPAPR_TCE_IOMMU config
option and configure VFIO as required.
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
At the moment all queues in a multiqueue adapter will serialise
against the IOMMU table lock. This is proving to be a big issue,
especially with 10Gbit ethernet.
This patch creates 4 pools and tries to spread the load across
them. If the table is under 1GB in size we revert back to the
original behaviour of 1 pool and 1 largealloc pool.
We create a hash to map CPUs to pools. Since we prefer interrupts to
be affinitised to primary CPUs, without some form of hashing we are
very likely to end up using the same pool. As an example, POWER7
has 4 way SMT and with 4 pools all primary threads will map to the
same pool.
The largealloc pool is reduced from 1/2 to 1/4 of the space to
partially offset the overhead of breaking the table up into pools.
Some performance numbers were obtained with a Chelsio T3 adapter on
two POWER7 boxes, running a 100 session TCP round robin test.
Performance improved 69% with this patch applied.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Sometimes this is used to hold a simple offset, and sometimes
it is used to hold a pointer. This patch changes it to a union containing
void * and dma_addr_t. get/set accessors are also provided, because it was
getting a bit ugly to get to the actual data.
Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
As <asm/iommu.h> doesn't contain any other hardware specific definitions
but only interfaces.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Both arch/powerpc/platforms/cell/iommu.c and arch/powerpc/platforms/ps3/mm.c
contain the same Cell IOMMU page table entry definitions. Extract them and move
them to <asm/iommu.h>, while adding a CBE_ prefix.
This also allows them to be used by drivers.
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
After the merge of the 32 and 64bit DMA code, dma_direct_ops lost
their map/unmap_single() functions but gained map/unmap_page(). This
caused a problem for Cell because Cell's dma_iommu_fixed_ops called
the dma_direct_ops if the fixed linear mapping was to be used or the
iommu ops if the dynamic window was to be used. So in order to fix
this problem we need to update the 64bit DMA code to use
map/unmap_page.
First, we update the generic IOMMU code so that iommu_map_single()
becomes iommu_map_page() and iommu_unmap_single() becomes
iommu_unmap_page(). Then we propagate these changes up through all
the callers of these two functions and in the process update all the
dma_mapping_ops so that they have map/unmap_page rahter than
map/unmap_single. We can do this because on 64bit there is no HIGHMEM
memory so map/unmap_page ends up performing exactly the same function
as map/unmap_single, just taking different arguments.
This has no affect on drivers because the dma_map_single_attrs() just
ends up calling the map_page() function of the appropriate
dma_mapping_ops and similarly the dma_unmap_single_attrs() calls
unmap_page().
This fixes an oops on Cell blades, which oops on boot without this
because they call dma_direct_ops.map_single, which is NULL.
Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
from include/asm-powerpc. This is the result of a
mkdir arch/powerpc/include/asm
git mv include/asm-powerpc/* arch/powerpc/include/asm
Followed by a few documentation/comment fixups and a couple of places
where <asm-powepc/...> was being used explicitly. Of the latter only
one was outside the arch code and it is a driver only built for powerpc.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
