Commit Graph

12 Commits

Author SHA1 Message Date
Wei Yang
038adc2f58 core: replace getpagesize() with qemu_real_host_page_size
There are three page size in qemu:

  real host page size
  host page size
  target page size

All of them have dedicate variable to represent. For the last two, we
use the same form in the whole qemu project, while for the first one we
use two forms: qemu_real_host_page_size and getpagesize().

qemu_real_host_page_size is defined to be a replacement of
getpagesize(), so let it serve the role.

[Note] Not fully tested for some arch or device.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191013021145.16011-3-richardw.yang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-10-26 15:38:06 +02:00
Eric Auger
d7d8783647 vfio: Turn the container error into an Error handle
The container error integer field is currently used to store
the first error potentially encountered during any
vfio_listener_region_add() call. However this fails to propagate
detailed error messages up to the vfio_connect_container caller.
Instead of using an integer, let's use an Error handle.

Messages are slightly reworded to accomodate the propagation.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-10-04 18:49:18 +02:00
David Hildenbrand
905b7ee4d6 exec: Introduce qemu_maxrampagesize() and rename qemu_getrampagesize()
Rename qemu_getrampagesize() to qemu_minrampagesize(). While at it,
properly rename find_max_supported_pagesize() to
find_min_backend_pagesize().

s390x is actually interested into the maximum ram pagesize, so
introduce and use qemu_maxrampagesize().

Add a TODO, indicating that looking at any mapped memory backends is not
100% correct in some cases.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190417113143.5551-3-david@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-04-25 13:47:27 +02:00
Alexey Kardashevskiy
3cdd801b0b vfio/spapr: Rename local systempagesize variable
The "systempagesize" name suggests that it is the host system page size
while it is the smallest page size of memory backing the guest RAM so
let's rename it to stop confusion. This should cause no behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20190227085149.38596-4-aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 10:50:59 +11:00
Alexey Kardashevskiy
1610799876 vfio/spapr: Fix indirect levels calculation
The current code assumes that we can address more bits on a PCI bus
for DMA than we really can but there is no way knowing the actual limit.

This makes a better guess for the number of levels and if the kernel
fails to allocate that, this increases the level numbers till succeeded
or reached the 64bit limit.

This adds levels to the trace point.

This may cause the kernel to warn about failed allocation:
   [65122.837458] Failed to allocate a TCE memory, level shift=28
which might happen if MAX_ORDER is not large enough as it can vary:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/Kconfig?h=v5.0-rc2#n727

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20190227085149.38596-3-aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 10:50:59 +11:00
Alexey Kardashevskiy
c26bc185b7 vfio/spapr: Allow backing bigger guest IOMMU pages with smaller physical pages
At the moment the PPC64/pseries guest only supports 4K/64K/16M IOMMU
pages and POWER8 CPU supports the exact same set of page size so
so far things worked fine.

However POWER9 supports different set of sizes - 4K/64K/2M/1G and
the last two - 2M and 1G - are not even allowed in the paravirt interface
(RTAS DDW) so we always end up using 64K IOMMU pages, although we could
back guest's 16MB IOMMU pages with 2MB pages on the host.

This stores the supported host IOMMU page sizes in VFIOContainer and uses
this later when creating a new DMA window. This uses the system page size
(64k normally, 2M/16M/1G if hugepages used) as the upper limit of
the IOMMU pagesize.

This changes the type of @pagesize to uint64_t as this is what
memory_region_iommu_get_min_page_size() returns and clz64() takes.

There should be no behavioral changes on platforms other than pseries.
The guest will keep using the IOMMU page size selected by the PHB pagesize
property as this only changes the underlying hardware TCE table
granularity.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-08-21 14:28:45 +10:00
Alexey Kardashevskiy
e100161b69 vfio, spapr: Fix levels calculation
The existing tries to round up the number of pages but @pages is always
calculated as the rounded up value minus one  which makes ctz64() always
return 0 and have create.levels always set 1.

This removes wrong "-1" and allows having more than 1 levels. This becomes
handy for >128GB guests with standard 64K pages as this requires blocks
with zone order 9 and the popular limit of CONFIG_FORCE_MAX_ZONEORDER=9
means that only blocks up to order 8 are allowed.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-09-15 10:29:48 +10:00
Alexey Kardashevskiy
3df9d74806 memory/iommu: QOM'fy IOMMU MemoryRegion
This defines new QOM object - IOMMUMemoryRegion - with MemoryRegion
as a parent.

This moves IOMMU-related fields from MR to IOMMU MR. However to avoid
dymanic QOM casting in fast path (address_space_translate, etc),
this adds an @is_iommu boolean flag to MR and provides new helper to
do simple cast to IOMMU MR - memory_region_get_iommu. The flag
is set in the instance init callback. This defines
memory_region_is_iommu as memory_region_get_iommu()!=NULL.

This switches MemoryRegion to IOMMUMemoryRegion in most places except
the ones where MemoryRegion may be an alias.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20170711035620.4232-2-aik@ozlabs.ru>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 12:04:41 +02:00
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
David Gibson
21bb3093e6 vfio/spapr: Remove stale ioctl() call
This ioctl() call to VFIO_IOMMU_SPAPR_TCE_REMOVE was left over from an
earlier version of the code and has since been folded into
vfio_spapr_remove_window().

It wasn't caught because although the argument structure has been removed,
the libc function remove() means this didn't trigger a compile failure.
The ioctl() was also almost certain to fail silently and harmlessly with
the bogus argument, so this wasn't caught in testing.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2016-07-18 10:40:27 +10:00
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
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