On sPAPR, virtio devices are connected to the PCI bus and use MSI-X.
Commit cc943c36fa has modified MSI-X
so that writes are made using the bus master address space and follow
the IOMMU path.
Unfortunately, the IOMMU address space address space does not have an
MSI window: the notification is silently dropped in unassigned_mem_write
instead of reaching the guest... The most visible effect is that all
virtio devices are non-functional on sPAPR since then. :(
This patch does the following:
1) map the MSI window into the IOMMU address space for each PHB
- since each PHB instantiates its own IOMMU address space, we
can safely map the window at a fixed address (SPAPR_PCI_MSI_WINDOW)
- no real need to keep the MSI window setup in a separate function,
the spapr_pci_msi_init() code moves to spapr_phb_realize().
2) kill the global MSI window as it is not needed in the end
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Currently SPAPR PHB keeps track of all allocated MSI (here and below
MSI stands for both MSI and MSIX) interrupt because
XICS used to be unable to reuse interrupts. This is a problem for
dynamic MSI reconfiguration which happens when guest reloads a driver
or performs PCI hotplug. Another problem is that the existing
implementation can enable MSI on 32 devices maximum
(SPAPR_MSIX_MAX_DEVS=32) and there is no good reason for that.
This makes use of new XICS ability to reuse interrupts.
This reorganizes MSI information storage in sPAPRPHBState. Instead of
static array of 32 descriptors (one per a PCI function), this patch adds
a GHashTable when @config_addr is a key and (first_irq, num) pair is
a value. GHashTable can dynamically grow and shrink so the initial limit
of 32 devices is gone.
This changes migration stream as @msi_table was a static array while new
@msi_devs is a dynamic hash table. This adds temporary array which is
used for migration, it is populated in "spapr_pci"::pre_save() callback
and expanded into the hash table in post_load() callback. Since
the destination side does not know the number of MSI-enabled devices
in advance and cannot pre-allocate the temporary array to receive
migration state, this makes use of new VMSTATE_STRUCT_VARRAY_ALLOC macro
which allocates the array automatically.
This resets the MSI configuration space when interrupts are released by
the ibm,change-msi RTAS call.
This fixed traces to be more informative.
This changes vmstate_spapr_pci_msi name from "...lsi" to "...msi" which
was incorrect by accident. As the internal representation changed,
thus bumps migration version number.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[agraf: drop g_malloc_n usage]
Signed-off-by: Alexander Graf <agraf@suse.de>
The patch adds a spapr-pci-vfio-host-bridge device type
which is a PCI Host Bridge with VFIO support. The new device
inherits from the spapr-pci-host-bridge device and adds an "iommu"
property which is an IOMMU id. This ID represents a minimal entity
for which IOMMU isolation can be guaranteed. In SPAPR architecture IOMMU
group is called a Partitionable Endpoint (PE).
Current implementation supports one IOMMU id per QEMU VFIO PHB. Since
SPAPR allows multiple PHB for no extra cost, this does not seem to
be a problem. This limitation may change in the future though.
Example of use:
Configure and Add 3 functions of a multifunctional device to QEMU:
(the NEC PCI USB card is used as an example here):
-device spapr-pci-vfio-host-bridge,id=USB,iommu=4,index=7 \
-device vfio-pci,host=4:0:1.0,addr=1.0,bus=USB,multifunction=true
-device vfio-pci,host=4:0:1.1,addr=1.1,bus=USB
-device vfio-pci,host=4:0:1.2,addr=1.2,bus=USB
where:
* index=7 is a QEMU PHB index (used as source for MMIO/MSI/IO windows
offset);
* iommu=4 is an IOMMU id which can be found in sysfs:
[aik@vpl2 ~]$ cd /sys/bus/pci/devices/0004:00:00.0/
[aik@vpl2 0004:00:00.0]$ ls -l iommu_group
lrwxrwxrwx 1 root root 0 Jun 5 12:49 iommu_group -> ../../../kernel/iommu_groups/4
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
This removes window_size as it is basically a copy of nb_table
shifted by SPAPR_TCE_PAGE_SHIFT. As new dynamic DMA windows are
going to support windows as big as the entire RAM and this number
will be bigger that 32 capacity, we will have to do something
about @window_size anyway and removal seems to be the right way to go.
This removes dma_window_start/dma_window_size from sPAPRPHBState as
they are no longer used.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
At the moment sPAPRPHBState contains a @tcet pointer to the only
TCE table. However sPAPR spec allows having more than one DMA window.
Since the TCE object is already a child of SPAPR PHB object, there is
no need to keep an additional pointer to it in sPAPRPHBState so remove it.
This changes the way sPAPRPHBState::reset performs reset of sPAPRTCETable
objects.
This changes the default DMA window properties calculation.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
Currently the default DMA window is represented by a single MemoryRegion.
However there can be more than just one window so we need
a "root" memory region to be separated from the actual DMA window(s).
This introduces a "root" IOMMU memory region and adds a subregion for
the default DMA 32bit window. Following patches will add other
subregion(s).
This initializes a default DMA window subregion size to the guest RAM
size as this window can be switched into "bypass" mode which implements
direct DMA mapping.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
The spapr-pci PHB initializes IOMMU for emulated devices only.
The upcoming VFIO support will do it different. However both emulated
and VFIO PHB types share most of the initialization code.
For the type specific things a new finish_realize() callback is
introduced.
This introduces sPAPRPHBClass derived from PCIHostBridgeClass and
adds the callback pointer.
This implements finish_realize() for emulated devices.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[agraf: Fix compilation]
Signed-off-by: Alexander Graf <agraf@suse.de>
On the sPAPR platform a guest allocates MSI/MSIX vectors via RTAS
hypercalls which return global IRQ numbers to a guest so it only
operates with those and never touches MSIMessage.
Therefore MSIMessage handling is completely hidden in QEMU.
Previously every sPAPR PCI host bridge implemented its own MSI window
to catch msi_notify()/msix_notify() calls from QEMU devices (virtio-pci
or vfio) and route them to the guest via qemu_pulse_irq().
MSIMessage used to be encoded as:
.addr - address within the PHB MSI window;
.data - the device index on PHB plus vector number.
The MSI MR write function translated this MSIMessage to a global IRQ
number and called qemu_pulse_irq().
However the total number of IRQs is not really big (at the moment it is
1024 IRQs starting from 4096) and even 16bit data field of MSIMessage
seems to be enough to store an IRQ number there.
This simplifies MSI handling in sPAPR PHB. Specifically, this does:
1. remove a MSI window from a PHB;
2. add a single memory region for all MSIs to sPAPREnvironment
and spapr_pci_msi_init() to initialize it;
3. encode MSIMessage as:
* .addr - a fixed address of SPAPR_PCI_MSI_WINDOW==0x40000000000ULL;
* .data as an IRQ number.
4. change IRQ allocator to align first IRQ number in a block for MSI.
MSI uses lower bits to specify the vector number so the first IRQ has to
be aligned. MSIX does not need any special allocator though.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
This adds the necessary support for saving the state of the PAPR virtual
PCI host bridge (or host bridges).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Message-id: 1374175984-8930-10-git-send-email-aliguori@us.ibm.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Use the new iommu support in the memory core for iommu support. The only
user, spapr, is also converted, but it still provides a DMAContext
interface until the non-PCI bits switch to AddressSpace.
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
[ Do not calls memory_region_del_subregion() on the device's
bus_master_enable_region, it is an alias; return an AddressSpace
from the IOMMU hook and remove the destructor hook. - David Gibson ]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The TCE table is currently returned as a DMAContext, and non-type-safe
APIs are called later passing back the DMAContext. Since we want to move
away from DMAContext, use an opaque type instead, and add an accessor
to retrieve the DMAContext from it.
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Many of these should be cleaned up with proper qdev-/QOM-ification.
Right now there are many catch-all headers in include/hw/ARCH depending
on cpu.h, and this makes it necessary to compile these files per-target.
However, fixing this does not belong in these patches.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
