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  1. 17 1月, 2017 1 次提交
  3. 10 1月, 2017 2 次提交
  5. 22 12月, 2016 2 次提交
  7. 31 10月, 2016 2 次提交
    • A
      memory: Don't use memcpy for ram_device regions · 4a2e242b
      由 Alex Williamson 提交于 
      With a vfio assigned device we lay down a base MemoryRegion registered
as an IO region, giving us read & write accessors.  If the region
supports mmap, we lay down a higher priority sub-region MemoryRegion
on top of the base layer initialized as a RAM device pointer to the
mmap.  Finally, if we have any quirks for the device (ie. address
ranges that need additional virtualization support), we put another IO
sub-region on top of the mmap MemoryRegion.  When this is flattened,
we now potentially have sub-page mmap MemoryRegions exposed which
cannot be directly mapped through KVM.

This is as expected, but a subtle detail of this is that we end up
with two different access mechanisms through QEMU.  If we disable the
mmap MemoryRegion, we make use of the IO MemoryRegion and service
accesses using pread and pwrite to the vfio device file descriptor.
If the mmap MemoryRegion is enabled and results in one of these
sub-page gaps, QEMU handles the access as RAM, using memcpy to the
mmap.  Using either pread/pwrite or the mmap directly should be
correct, but using memcpy causes us problems.  I expect that not only
does memcpy not necessarily honor the original width and alignment in
performing a copy, but it potentially also uses processor instructions
not intended for MMIO spaces.  It turns out that this has been a
problem for Realtek NIC assignment, which has such a quirk that
creates a sub-page mmap MemoryRegion access.

To resolve this, we disable memory_access_is_direct() for ram_device
regions since QEMU assumes that it can use memcpy for those regions.
Instead we access through MemoryRegionOps, which replaces the memcpy
with simple de-references of standard sizes to the host memory.

With this patch we attempt to provide unrestricted access to the RAM
device, allowing byte through qword access as well as unaligned
access.  The assumption here is that accesses initiated by the VM are
driven by a device specific driver, which knows the device
capabilities.  If unaligned accesses are not supported by the device,
we don't want them to work in a VM by performing multiple aligned
accesses to compose the unaligned access.  A down-side of this
philosophy is that the xp command from the monitor attempts to use
the largest available access weidth, unaware of the underlying
device.  Using memcpy had this same restriction, but at least now an
operator can dump individual registers, even if blocks of device
memory may result in access widths beyond the capabilities of a
given device (RTL NICs only support up to dword).
Reported-by: NThorsten Kohfeldt <thorsten.kohfeldt@gmx.de>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
      4a2e242b
    • A
      memory: Replace skip_dump flag with "ram_device" · 21e00fa5
      由 Alex Williamson 提交于 
      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: NAlex Williamson <alex.williamson@redhat.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
      21e00fa5
  9. 24 10月, 2016 2 次提交
  11. 27 9月, 2016 3 次提交
    • P
      migration: sync all address spaces · 9c1f8f44
      由 Paolo Bonzini 提交于 
      Migrating a VM during reboot sometimes results in differences
between the source and destination in the SMRAM area.

This is because migration_bitmap_sync() only fetches from KVM
the dirty log of address_space_memory.  SMRAM memory slots
are ignored and the modifications to SMRAM are not sent to the
destination.
Reported-by: NHe Rongguang <herongguang.he@huawei.com>
Reviewed-by: NHe Rongguang <herongguang.he@huawei.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      9c1f8f44
    • P
      memory: introduce IOMMUOps.notify_flag_changed · 5bf3d319
      由 Peter Xu 提交于 
      The new interface can be used to replace the old notify_started() and
notify_stopped(). Meanwhile it provides explicit flags so that IOMMUs
can know what kind of notifications it is requested for.
Acked-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <1474606948-14391-3-git-send-email-peterx@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      5bf3d319
    • P
      memory: introduce IOMMUNotifier and its caps · cdb30812
      由 Peter Xu 提交于 
      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: NPeter Xu <peterx@redhat.com>
Message-Id: <1474606948-14391-2-git-send-email-peterx@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      cdb30812
  13. 04 7月, 2016 2 次提交
    • P
      memory: Assert that memory_region_init_rom_device() ops aren't NULL · 39e0b03d
      由 Peter Maydell 提交于 
      It doesn't make sense to pass a NULL ops argument to
memory_region_init_rom_device(), because the effect will
be that if the guest tries to write to the memory region
then QEMU will segfault. Catch the bug earlier by sanity
checking the arguments to this function, and remove the
misleading documentation that suggests that passing NULL
might be sensible.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1467122287-24974-4-git-send-email-peter.maydell@linaro.org
      39e0b03d
    • P
      memory: Provide memory_region_init_rom() · a1777f7f
      由 Peter Maydell 提交于 
      Provide a new helper function memory_region_init_rom() for memory
regions which are read-only (and unlike those created by
memory_region_init_rom_device() don't have special behaviour
for writes). This has the same behaviour as calling
memory_region_init_ram() and then memory_region_set_readonly()
(which is what we do today in boards with pure ROMs) but is a
more easily discoverable API for the purpose.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1467122287-24974-2-git-send-email-peter.maydell@linaro.org
      a1777f7f
  15. 01 7月, 2016 1 次提交
  17. 22 6月, 2016 1 次提交
  19. 29 5月, 2016 3 次提交
  21. 23 5月, 2016 1 次提交
  23. 19 5月, 2016 1 次提交
  25. 23 3月, 2016 1 次提交
  27. 07 3月, 2016 2 次提交
  29. 25 2月, 2016 3 次提交
  31. 23 2月, 2016 1 次提交
    • P
      include: Clean up includes · 90ce6e26
      由 Peter Maydell 提交于 
      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.

NB: If this commit breaks compilation for your out-of-tree
patchseries or fork, then you need to make sure you add
#include "qemu/osdep.h" to any new .c files that you have.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NEric Blake <eblake@redhat.com>
      90ce6e26
  33. 21 1月, 2016 1 次提交
    • P
      memory: Add address_space_init_shareable() · f0c02d15
      由 Peter Crosthwaite 提交于 
      This will either create a new AS or return a pointer to an
already existing equivalent one, if we have already created
an AS for the specified root memory region.

The motivation is to reuse address spaces as much as possible.
It's going to be quite common that bus masters out in device land
have pointers to the same memory region for their mastering yet
each will need to create its own address space. Let the memory
API implement sharing for them.

Aside from the perf optimisations, this should reduce the amount
of redundant output on info mtree as well.

Thee returned value will be malloced, but the malloc will be
automatically freed when the AS runs out of refs.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
[PMM: dropped check for NULL root as unused; added doc-comment;
 squashed Peter C's reference-counting patch into this one;
 don't compare name string when deciding if we can share ASes;
 read as->malloced before the unref of as->root to avoid possible
 read-after-free if as->root was the owner of as]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Acked-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>
      f0c02d15
  35. 18 12月, 2015 6 次提交
  37. 06 10月, 2015 1 次提交
    • D
      memory: Allow replay of IOMMU mapping notifications · a788f227
      由 David Gibson 提交于 
      When we have guest visible IOMMUs, we allow notifiers to be registered
which will be informed of all changes to IOMMU mappings.  This is used by
vfio to keep the host IOMMU mappings in sync with guest IOMMU mappings.

However, unlike with a memory region listener, an iommu notifier won't be
told about any mappings which already exist in the (guest) IOMMU at the
time it is registered.  This can cause problems if hotplugging a VFIO
device onto a guest bus which had existing guest IOMMU mappings, but didn't
previously have an VFIO devices (and hence no host IOMMU mappings).

This adds a memory_region_iommu_replay() function to handle this case.  It
replays any existing mappings in an IOMMU memory region to a specified
notifier.  Because the IOMMU memory region doesn't internally remember the
granularity of the guest IOMMU it has a small hack where the caller must
specify a granularity at which to replay mappings.

If there are finer mappings in the guest IOMMU these will be reported in
the iotlb structures passed to the notifier which it must handle (probably
causing it to flag an error).  This isn't new - the VFIO iommu notifier
must already handle notifications about guest IOMMU mappings too short
for it to represent in the host IOMMU.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NLaurent Vivier <lvivier@redhat.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
      a788f227
  39. 11 9月, 2015 2 次提交
  41. 13 8月, 2015 1 次提交
  43. 24 7月, 2015 1 次提交