Commit Graph

53 Commits

Author SHA1 Message Date
Jose Ricardo Ziviani 38d49e8c15 vfio: enable 8-byte reads/writes to vfio
This patch enables 8-byte writes and reads to VFIO. Such implemention
is already done but it's missing the 'case' to handle such accesses in
both vfio_region_write and vfio_region_read and the MemoryRegionOps:
impl.max_access_size and impl.min_access_size.

After this patch, 8-byte writes such as:

qemu_mutex_lock locked mutex 0x10905ad8
vfio_region_write  (0001:03:00.0:region1+0xc0, 0x4140c, 4)
vfio_region_write  (0001:03:00.0:region1+0xc4, 0xa0000, 4)
qemu_mutex_unlock unlocked mutex 0x10905ad8

goes like this:

qemu_mutex_lock locked mutex 0x10905ad8
vfio_region_write  (0001:03:00.0:region1+0xc0, 0xbfd0008, 8)
qemu_mutex_unlock unlocked mutex 0x10905ad8

Signed-off-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-05-03 14:52:34 -06:00
Jose Ricardo Ziviani 15126cba86 vfio: Set MemoryRegionOps:max_access_size and min_access_size
Sets valid.max_access_size and valid.min_access_size to ensure safe
8-byte accesses to vfio. Today, 8-byte accesses are broken into pairs
of 4-byte calls that goes unprotected:

qemu_mutex_lock locked mutex 0x10905ad8
  vfio_region_write  (0001:03:00.0:region1+0xc0, 0x2020c, 4)
qemu_mutex_unlock unlocked mutex 0x10905ad8
qemu_mutex_lock locked mutex 0x10905ad8
  vfio_region_write  (0001:03:00.0:region1+0xc4, 0xa0000, 4)
qemu_mutex_unlock unlocked mutex 0x10905ad8

which occasionally leads to:

qemu_mutex_lock locked mutex 0x10905ad8
  vfio_region_write  (0001:03:00.0:region1+0xc0, 0x2030c, 4)
qemu_mutex_unlock unlocked mutex 0x10905ad8
qemu_mutex_lock locked mutex 0x10905ad8
  vfio_region_write  (0001:03:00.0:region1+0xc0, 0x1000c, 4)
qemu_mutex_unlock unlocked mutex 0x10905ad8
qemu_mutex_lock locked mutex 0x10905ad8
  vfio_region_write  (0001:03:00.0:region1+0xc4, 0xb0000, 4)
qemu_mutex_unlock unlocked mutex 0x10905ad8
qemu_mutex_lock locked mutex 0x10905ad8
  vfio_region_write  (0001:03:00.0:region1+0xc4, 0xa0000, 4)
qemu_mutex_unlock unlocked mutex 0x10905ad8

causing strange errors in guest OS. With this patch, such accesses
are protected by the same lock guard:

qemu_mutex_lock locked mutex 0x10905ad8
vfio_region_write  (0001:03:00.0:region1+0xc0, 0x2000c, 4)
vfio_region_write  (0001:03:00.0:region1+0xc4, 0xb0000, 4)
qemu_mutex_unlock unlocked mutex 0x10905ad8

This happens because the 8-byte write should be broken into 4-byte
writes by memory.c:access_with_adjusted_size() in order to be under
the same lock. Today, it's done in exec.c:address_space_write_continue()
which was able to handle only 4 bytes due to a zero'ed
valid.max_access_size (see exec.c:memory_access_size()).

Signed-off-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-05-03 14:52:34 -06:00
Peter Xu 698feb5e13 memory: add section range info for IOMMU notifier
In this patch, IOMMUNotifier.{start|end} are introduced to store section
information for a specific notifier. When notification occurs, we not
only check the notification type (MAP|UNMAP), but also check whether the
notified iova range overlaps with the range of specific IOMMU notifier,
and skip those notifiers if not in the listened range.

When removing an region, we need to make sure we removed the correct
VFIOGuestIOMMU by checking the IOMMUNotifier.start address as well.

This patch is solving the problem that vfio-pci devices receive
duplicated UNMAP notification on x86 platform when vIOMMU is there. The
issue is that x86 IOMMU has a (0, 2^64-1) IOMMU region, which is
splitted by the (0xfee00000, 0xfeefffff) IRQ region. AFAIK
this (splitted IOMMU region) is only happening on x86.

This patch also helps vhost to leverage the new interface as well, so
that vhost won't get duplicated cache flushes. In that sense, it's an
slight performance improvement.

Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1491562755-23867-2-git-send-email-peterx@redhat.com>
[ehabkost: included extra vhost_iommu_region_del() change from Peter Xu]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2017-04-20 15:22:41 -03:00
Peter Xu dfbd90e5b9 vfio: allow to notify unmap for very large region
Linux vfio driver supports to do VFIO_IOMMU_UNMAP_DMA for a very big
region. This can be leveraged by QEMU IOMMU implementation to cleanup
existing page mappings for an entire iova address space (by notifying
with an IOTLB with extremely huge addr_mask). However current
vfio_iommu_map_notify() does not allow that. It make sure that all the
translated address in IOTLB is falling into RAM range.

The check makes sense, but it should only be a sensible checker for
mapping operations, and mean little for unmap operations.

This patch moves this check into map logic only, so that we'll get
faster unmap handling (no need to translate again), and also we can then
better support unmapping a very big region when it covers non-ram ranges
or even not-existing ranges.

Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:31 +02:00
Peter Xu 4a4b88fbe1 vfio: introduce vfio_get_vaddr()
A cleanup for vfio_iommu_map_notify(). Now we will fetch vaddr even if
the operation is unmap, but it won't hurt much.

One thing to mention is that we need the RCU read lock to protect the
whole translation and map/unmap procedure.

Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:31 +02:00
Peter Xu 3213835720 vfio: trace map/unmap for notify as well
We traces its range, but we don't know whether it's a MAP/UNMAP. Let's
dump it as well.

Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:31 +02:00
Yongji Xie 95251725e3 vfio: Add support for mmapping sub-page MMIO BARs
Now the kernel commit 05f0c03fbac1 ("vfio-pci: Allow to mmap
sub-page MMIO BARs if the mmio page is exclusive") allows VFIO
to mmap sub-page BARs. This is the corresponding QEMU patch.
With those patches applied, we could passthrough sub-page BARs
to guest, which can help to improve IO performance for some devices.

In this patch, we expand MemoryRegions of these sub-page
MMIO BARs to PAGE_SIZE in vfio_pci_write_config(), so that
the BARs could be passed to KVM ioctl KVM_SET_USER_MEMORY_REGION
with a valid size. The expanding size will be recovered when
the base address of sub-page BAR is changed and not page aligned
any more in guest. And we also set the priority of these BARs'
memory regions to zero in case of overlap with BARs which share
the same page with sub-page BARs in guest.

Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-31 09:53:04 -06:00
Alex Williamson 24acf72b9a vfio: Handle zero-length sparse mmap ranges
As reported in the link below, user has a PCI device with a 4KB BAR
which contains the MSI-X table.  This seems to hit a corner case in
the kernel where the region reports being mmap capable, but the sparse
mmap information reports a zero sized range.  It's not entirely clear
that the kernel is incorrect in doing this, but regardless, we need
to handle it.  To do this, fill our mmap array only with non-zero
sized sparse mmap entries and add an error return from the function
so we can tell the difference between nr_mmaps being zero based on
sparse mmap info vs lack of sparse mmap info.

NB, this doesn't actually change the behavior of the device, it only
removes the scary "Failed to mmap ... Performance may be slow" error
message.  We cannot currently create an mmap over the MSI-X table.

Link: http://lists.nongnu.org/archive/html/qemu-discuss/2016-10/msg00009.html
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-31 09:53:03 -06:00
Alex Williamson 21e00fa55f memory: Replace skip_dump flag with "ram_device"
Setting skip_dump on a MemoryRegion allows us to modify one specific
code path, but the restriction we're trying to address encompasses
more than that.  If we have a RAM MemoryRegion backed by a physical
device, it not only restricts our ability to dump that region, but
also affects how we should manipulate it.  Here we recognize that
MemoryRegions do not change to sometimes allow dumps and other times
not, so we replace setting the skip_dump flag with a new initializer
so that we know exactly the type of region to which we're applying
this behavior.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-31 09:53:03 -06:00
Eric Auger 59f7d6743c vfio: Pass an error object to vfio_get_device
Pass an error object to prepare for migration to VFIO-PCI realize.

In vfio platform vfio_base_device_init we currently just report the
error. Subsequent patches will propagate the error up to the realize
function.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:58:00 -06:00
Eric Auger 1b808d5be0 vfio: Pass an error object to vfio_get_group
Pass an error object to prepare for migration to VFIO-PCI realize.

For the time being let's just simply report the error in
vfio platform's vfio_base_device_init(). A subsequent patch will
duly propagate the error up to vfio_platform_realize.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:59 -06:00
Eric Auger 01905f58f1 vfio: Pass an Error object to vfio_connect_container
The error is currently simply reported in vfio_get_group. Don't
bother too much with the prefix which will be handled at upper level,
later on.

Also return an error value in case container->error is not 0 and
the container is teared down.

On vfio_spapr_remove_window failure, we also report an error whereas
it was silent before.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:59 -06:00
Peter Xu cdb3081269 memory: introduce IOMMUNotifier and its caps
IOMMU Notifier list is used for notifying IO address mapping changes.
Currently VFIO is the only user.

However it is possible that future consumer like vhost would like to
only listen to part of its notifications (e.g., cache invalidations).

This patch introduced IOMMUNotifier and IOMMUNotfierFlag bits for a
finer grained control of it.

IOMMUNotifier contains a bitfield for the notify consumer describing
what kind of notification it is interested in. Currently two kinds of
notifications are defined:

- IOMMU_NOTIFIER_MAP:    for newly mapped entries (additions)
- IOMMU_NOTIFIER_UNMAP:  for entries to be removed (cache invalidates)

When registering the IOMMU notifier, we need to specify one or multiple
types of messages to listen to.

When notifications are triggered, its type will be checked against the
notifier's type bits, and only notifiers with registered bits will be
notified.

(For any IOMMU implementation, an in-place mapping change should be
 notified with an UNMAP followed by a MAP.)

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1474606948-14391-2-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-27 08:59:16 +02:00
Markus Armbruster a9c94277f0 Use #include "..." for our own headers, <...> for others
Tracked down with an ugly, brittle and probably buggy Perl script.

Also move includes converted to <...> up so they get included before
ours where that's obviously okay.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
2016-07-12 16:19:16 +02:00
Alexey Kardashevskiy 2e4109de8e vfio/spapr: Create DMA window dynamically (SPAPR IOMMU v2)
New VFIO_SPAPR_TCE_v2_IOMMU type supports dynamic DMA window management.
This adds ability to VFIO common code to dynamically allocate/remove
DMA windows in the host kernel when new VFIO container is added/removed.

This adds a helper to vfio_listener_region_add which makes
VFIO_IOMMU_SPAPR_TCE_CREATE ioctl and adds just created IOMMU into
the host IOMMU list; the opposite action is taken in
vfio_listener_region_del.

When creating a new window, this uses heuristic to decide on the TCE table
levels number.

This should cause no guest visible change in behavior.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[dwg: Added some casts to prevent printf() warnings on certain targets
 where the kernel headers' __u64 doesn't match uint64_t or PRIx64]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-07-05 14:31:08 +10:00
Alexey Kardashevskiy f4ec5e26ed vfio: Add host side DMA window capabilities
There are going to be multiple IOMMUs per a container. This moves
the single host IOMMU parameter set to a list of VFIOHostDMAWindow.

This should cause no behavioral change and will be used later by
the SPAPR TCE IOMMU v2 which will also add a vfio_host_win_del() helper.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-07-05 14:31:08 +10:00
Alexey Kardashevskiy 318f67ce13 vfio: spapr: Add DMA memory preregistering (SPAPR IOMMU v2)
This makes use of the new "memory registering" feature. The idea is
to provide the userspace ability to notify the host kernel about pages
which are going to be used for DMA. Having this information, the host
kernel can pin them all once per user process, do locked pages
accounting (once) and not spent time on doing that in real time with
possible failures which cannot be handled nicely in some cases.

This adds a prereg memory listener which listens on address_space_memory
and notifies a VFIO container about memory which needs to be
pinned/unpinned. VFIO MMIO regions (i.e. "skip dump" regions) are skipped.

The feature is only enabled for SPAPR IOMMU v2. The host kernel changes
are required. Since v2 does not need/support VFIO_IOMMU_ENABLE, this does
not call it when v2 is detected and enabled.

This enforces guest RAM blocks to be host page size aligned; however
this is not new as KVM already requires memory slots to be host page
size aligned.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[dwg: Fix compile error on 32-bit host]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-07-05 14:30:54 +10:00
Alexey Kardashevskiy d22d8956b1 memory: Add MemoryRegionIOMMUOps.notify_started/stopped callbacks
The IOMMU driver may change behavior depending on whether a notifier
client is present.  In the case of POWER, this represents a change in
the visibility of the IOTLB, for other drivers such as intel-iommu and
future AMD-Vi emulation, notifier support is not yet enabled and this
provides the opportunity to flag that incompatibility.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
[new log & extracted from [PATCH qemu v17 12/12] spapr_iommu, vfio, memory: Notify IOMMU about starting/stopping listening]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-06-30 13:00:23 -06:00
Alexey Kardashevskiy f682e9c244 memory: Add reporting of supported page sizes
Every IOMMU has some granularity which MemoryRegionIOMMUOps::translate
uses when translating, however this information is not available outside
the translate context for various checks.

This adds a get_min_page_size callback to MemoryRegionIOMMUOps and
a wrapper for it so IOMMU users (such as VFIO) can know the minimum
actual page size supported by an IOMMU.

As IOMMU MR represents a guest IOMMU, this uses TARGET_PAGE_SIZE
as fallback.

This removes vfio_container_granularity() and uses new helper in
memory_region_iommu_replay() when replaying IOMMU mappings on added
IOMMU memory region.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
[dwg: Removed an unnecessary calculation]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-06-22 11:13:09 +10:00
Gavin Shan d917e88d85 vfio: Fix broken EEH
vfio_eeh_container_op() is the backend that communicates with
host kernel to support EEH functionality in QEMU. However, the
functon should return the value from host kernel instead of 0
unconditionally.

dwg: Specifically the problem occurs for the handful of EEH
sub-operations which can return a non-zero, non-error result.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
[dwg: clarification to commit message]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-06-17 15:59:18 +10:00
Paolo Bonzini 02d0e09503 os-posix: include sys/mman.h
qemu/osdep.h checks whether MAP_ANONYMOUS is defined, but this check
is bogus without a previous inclusion of sys/mman.h.  Include it in
sysemu/os-posix.h and remove it from everywhere else.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 18:39:03 +02:00
Alexey Kardashevskiy f1f9365019 vfio: Check that IOMMU MR translates to system address space
At the moment IOMMU MR only translate to the system memory.
However if some new code changes this, we will need clear indication why
it is not working so here is the check.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-05-26 11:12:09 -06:00
Alexey Kardashevskiy d78c19b5cf memory: Fix IOMMU replay base address
Since a788f227 "memory: Allow replay of IOMMU mapping notifications"
when new VFIO listener is added, all existing IOMMU mappings are
replayed. However there is a problem that the base address of
an IOMMU memory region (IOMMU MR) is ignored which is not a problem
for the existing user (which is pseries) with its default 32bit DMA
window starting at 0 but it is if there is another DMA window.

This stores the IOMMU's offset_within_address_space and adjusts
the IOVA before calling vfio_dma_map/vfio_dma_unmap.

As the IOMMU notifier expects IOVA offset rather than the absolute
address, this also adjusts IOVA in sPAPR H_PUT_TCE handler before
calling notifier(s).

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-05-26 11:12:08 -06:00
Alexey Kardashevskiy 7a057b4fb9 vfio: Fix 128 bit handling when deleting region
7532d3cbf "vfio: Fix 128 bit handling" added support for 64bit IOMMU
memory regions when those are added to VFIO address space; however
removing code cannot cope with these as int128_get64() will fail on
1<<64.

This copies 128bit handling from region_add() to region_del().

Since the only machine type which is actually going to use 64bit IOMMU
is pseries and it never really removes them (instead it will dynamically
add/remove subregions), this should cause no behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-05-26 11:12:07 -06:00
Alex Williamson e61a424f05 vfio: Create device specific region info helper
Given a device specific region type and sub-type, find it.  Also
cleanup return point on error in vfio_get_region_info() so that we
always return 0 with a valid pointer or -errno and NULL.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:04:50 -06:00
Alex Williamson b53b0f696b vfio: Enable sparse mmap capability
The sparse mmap capability in a vfio region info allows vfio to tell
us which sub-areas of a region may be mmap'd.  Thus rather than
assuming a single mmap covers the entire region and later frobbing it
ourselves for things like the PCI MSI-X vector table, we can read that
directly from vfio.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 09:43:20 -06:00
Paolo Bonzini e81096b1c8 explicitly include linux/kvm.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:27 +02:00
Bandan Das 55efcc537d vfio: convert to 128 bit arithmetic calculations when adding mem regions
vfio_listener_region_add for a iommu mr results in
an overflow assert since iommu memory region is initialized
with UINT64_MAX. Convert calculations to 128 bit arithmetic
for iommu memory regions and let int128_get64 assert for non iommu
regions if there's an overflow.

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bandan Das <bsd@redhat.com>
[missed (end - 1) on 2nd trace call, move llsize closer to use]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-28 13:27:49 -06:00
David Gibson 3356128cd1 vfio: Eliminate vfio_container_ioctl()
vfio_container_ioctl() was a bad interface that bypassed abstraction
boundaries, had semantics that sat uneasily with its name, and was unsafe
in many realistic circumstances.  Now that spapr-pci-vfio-host-bridge has
been folded into spapr-pci-host-bridge, there are no more users, so remove
it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-16 09:55:11 +11:00
David Gibson 3153119e9b vfio: Start improving VFIO/EEH interface
At present the code handling IBM's Enhanced Error Handling (EEH) interface
on VFIO devices operates by bypassing the usual VFIO logic with
vfio_container_ioctl().  That's a poorly designed interface with unclear
semantics about exactly what can be operated on.

In particular it operates on a single vfio container internally (hence the
name), but takes an address space and group id, from which it deduces the
container in a rather roundabout way.  groupids are something that code
outside vfio shouldn't even be aware of.

This patch creates new interfaces for EEH operations.  Internally we
have vfio_eeh_container_op() which takes a VFIOContainer object
directly.  For external use we have vfio_eeh_as_ok() which determines
if an AddressSpace is usable for EEH (at present this means it has a
single container with exactly one group attached), and vfio_eeh_as_op()
which will perform an operation on an AddressSpace in the unambiguous case,
and otherwise returns an error.

This interface still isn't great, but it's enough of an improvement to
allow a number of cleanups in other places.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-16 09:55:10 +11:00
Alex Williamson db0da029a1 vfio: Generalize region support
Both platform and PCI vfio drivers create a "slow", I/O memory region
with one or more mmap memory regions overlayed when supported by the
device. Generalize this to a set of common helpers in the core that
pulls the region info from vfio, fills the region data, configures
slow mapping, and adds helpers for comleting the mmap, enable/disable,
and teardown.  This can be immediately used by the PCI MSI-X code,
which needs to mmap around the MSI-X vector table.

This also changes VFIORegion.mem to be dynamically allocated because
otherwise we don't know how the caller has allocated VFIORegion and
therefore don't know whether to unreference it to destroy the
MemoryRegion or not.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-10 20:03:16 -07:00
Alex Williamson 469002263a vfio: Wrap VFIO_DEVICE_GET_REGION_INFO
In preparation for supporting capability chains on regions, wrap
ioctl(VFIO_DEVICE_GET_REGION_INFO) so we don't duplicate the code for
each caller.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-10 09:39:07 -07:00
Peter Maydell c6eacb1ac0 hw/vfio: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-22-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:24 +00:00
David Gibson 508ce5eb00 vfio: Allow hotplug of containers onto existing guest IOMMU mappings
At present the memory listener used by vfio to keep host IOMMU mappings
in sync with the guest memory image assumes that if a guest IOMMU
appears, then it has no existing mappings.

This may not be true if a VFIO device is hotplugged onto a guest bus
which didn't previously include a VFIO device, and which has existing
guest IOMMU mappings.

Therefore, use the memory_region_register_iommu_notifier_replay()
function in order to fix this case, replaying existing guest IOMMU
mappings, bringing the host IOMMU into sync with the guest IOMMU.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-10-05 12:39:47 -06:00
David Gibson 7a140a57c6 vfio: Record host IOMMU's available IO page sizes
Depending on the host IOMMU type we determine and record the available page
sizes for IOMMU translation.  We'll need this for other validation in
future patches.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-10-05 12:38:41 -06:00
David Gibson 3898aad323 vfio: Check guest IOVA ranges against host IOMMU capabilities
The current vfio core code assumes that the host IOMMU is capable of
mapping any IOVA the guest wants to use to where we need.  However, real
IOMMUs generally only support translating a certain range of IOVAs (the
"DMA window") not a full 64-bit address space.

The common x86 IOMMUs support a wide enough range that guests are very
unlikely to go beyond it in practice, however the IOMMU used on IBM Power
machines - in the default configuration - supports only a much more limited
IOVA range, usually 0..2GiB.

If the guest attempts to set up an IOVA range that the host IOMMU can't
map, qemu won't report an error until it actually attempts to map a bad
IOVA.  If guest RAM is being mapped directly into the IOMMU (i.e. no guest
visible IOMMU) then this will show up very quickly.  If there is a guest
visible IOMMU, however, the problem might not show up until much later when
the guest actually attempt to DMA with an IOVA the host can't handle.

This patch adds a test so that we will detect earlier if the guest is
attempting to use IOVA ranges that the host IOMMU won't be able to deal
with.

For now, we assume that "Type1" (x86) IOMMUs can support any IOVA, this is
incorrect, but no worse than what we have already.  We can't do better for
now because the Type1 kernel interface doesn't tell us what IOVA range the
IOMMU actually supports.

For the Power "sPAPR TCE" IOMMU, however, we can retrieve the supported
IOVA range and validate guest IOVA ranges against it, and this patch does
so.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-10-05 12:38:13 -06:00
David Gibson ac6dc3894f vfio: Generalize vfio_listener_region_add failure path
If a DMA mapping operation fails in vfio_listener_region_add() it
checks to see if we've already completed initial setup of the
container.  If so it reports an error so the setup code can fail
gracefully, otherwise throws a hw_error().

There are other potential failure cases in vfio_listener_region_add()
which could benefit from the same logic, so move it to its own
fail: block.  Later patches can use this to extend other failure cases
to fail as gracefully as possible under the circumstances.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-10-05 12:37:02 -06:00
David Gibson ee0bf0e59b vfio: Remove unneeded union from VFIOContainer
Currently the VFIOContainer iommu_data field contains a union with
different information for different host iommu types.  However:
   * It only actually contains information for the x86-like "Type1" iommu
   * Because we have a common listener the Type1 fields are actually used
on all IOMMU types, including the SPAPR TCE type as well

In fact we now have a general structure for the listener which is unlikely
to ever need per-iommu-type information, so this patch removes the union.

In a similar way we can unify the setup of the vfio memory listener in
vfio_connect_container() that is currently split across a switch on iommu
type, but is effectively the same in both cases.

The iommu_data.release pointer was only needed as a cleanup function
which would handle potentially different data in the union.  With the
union gone, it too can be removed.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-10-05 12:36:08 -06:00
Alex Williamson 5e15d79b86 vfio: Change polarity of our no-mmap option
The default should be to allow mmap and new drivers shouldn't need to
expose an option or set it to other than the allocation default in
their initfn.  Take advantage of the experimental flag to change this
option to the correct polarity.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:44 -06:00
Daniel P. Berrange b6af097528 maint: remove / fix many doubled words
Many source files have doubled words (eg "the the", "to to",
and so on). Most of these can simply be removed, but a couple
were actual mis-spellings (eg "to to" instead of "to do").
There was even one triple word score "to to to" :-)

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:21:38 +03:00
Alexey Kardashevskiy f8d8a94400 vfio: Unregister IOMMU notifiers when container is destroyed
On systems with guest visible IOMMU, adding a new memory region onto
PCI bus calls vfio_listener_region_add() for every DMA window. This
installs a notifier for IOMMU memory regions. The notifier is supposed
to be removed vfio_listener_region_del(), however in the case of mixed
PHB (emulated + VFIO devices) when last VFIO device is unplugged and
container gets destroyed, all existing DMA windows stay alive altogether
with the notifiers which are on the linked list which head was in
the destroyed container.

This unregisters IOMMU memory region notifier when a container is
destroyed.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-07-06 12:15:15 -06:00
Paolo Bonzini 41063e1e7a exec: move rcu_read_lock/unlock to address_space_translate callers
Once address_space_translate will be called outside the BQL, the returned
MemoryRegion might disappear as soon as the RCU read-side critical section
ends.  Avoid this by moving the critical section to the callers.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1426684909-95030-3-git-send-email-pbonzini@redhat.com>
2015-04-30 16:55:32 +02:00
Gonglei 78e5b17f04 vfio: Remove superfluous '\n' around error_report()
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-03-10 08:15:33 +03:00
Gavin Shan 2aad88f4b0 sPAPR: Implement sPAPRPHBClass EEH callbacks
The patch implements sPAPRPHBClass EEH callbacks so that the EEH
RTAS requests can be routed to VFIO for further handling.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-03-09 15:00:08 +01:00
Samuel Pitoiset 6ee47c9008 vfio: allow to disable MMAP per device with -x-mmap=off option
Disabling MMAP support uses the slower read/write accesses but allows to
trace all MMIO accesses, which is not good for performance, but very
useful for reverse engineering PCI drivers. This option allows to
disable MMAP per device without a compile-time change.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-02 11:38:55 -07:00
Alexey Kardashevskiy 51b833f440 vfio: Make type1 listener symbols static
They are not used from anywhere but common.c which is where these are
defined so make them static.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-02 11:38:55 -07:00
Alexey Kardashevskiy 46f770d4a5 vfio: Add ioctl number to error report
This makes the error report more informative.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-02 11:38:54 -07:00
Alex Williamson 2e6e697e16 vfio: Use vfio type1 v2 IOMMU interface
The difference between v1 and v2 is fairly subtle, simply more
deterministic behavior for unmaps.  The v1 interface allows the user
to attempt to unmap sub-regions of previous mappings, returning
success with zero size if unable to comply.  This was a reflection of
the underlying IOMMU API.  The v2 interface requires that the user
may only unmap fully contained mappings, ie. an unmap cannot intersect
or bisect a previous mapping, but may cover multiple mappings.  QEMU
never made use of the sub-region v1 support anyway, so we can support
either v1 or v2.  We'll favor v2 since it's newer.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 10:25:44 -07:00
Paolo Bonzini 77a10d04d0 vfio: free dynamically-allocated data in instance_finalize
In order to enable out-of-BQL address space lookup, destruction of
devices needs to be split in two phases.

Unrealize is the first phase; once it complete no new accesses will
be started, but there may still be pending memory accesses can still
be completed.

The second part is freeing the device, which only happens once all memory
accesses are complete.  At this point the reference count has dropped to
zero, an RCU grace period must have completed (because the RCU-protected
FlatViews hold a reference to the device via memory_region_ref).  This is
when instance_finalize is called.

Freeing data belongs in an instance_finalize callback, because the
dynamically allocated memory can still be used after unrealize by the
pending memory accesses.

This starts the process by creating an instance_finalize callback and
freeing most of the dynamically-allocated data in instance_finalize.
Because instance_finalize is also called on error paths or also when
the device is actually not realized, the common code needs some changes
to be ready for this.  The error path in vfio_initfn can be simplified too.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 10:25:44 -07:00
Paolo Bonzini 217e9fdcad vfio: cleanup vfio_get_device error path, remove vfio_populate_device callback
Now that vfio_put_base_device is called unconditionally at instance_finalize
time, it can be called twice if vfio_populate_device fails.  This works
but it is slightly harder to follow.

Change vfio_get_device to not touch the vbasedev struct until it will
definitely succeed, moving the vfio_populate_device call back to vfio-pci.
This way, vfio_put_base_device will only be called once.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 10:25:44 -07:00