vfio: Destroy memory regions

Somehow this has been lurking for a while; we remove our subregions
from the base BAR and VGA region mappings, but we don't destroy them,
creating a leak and more serious problems when we try to migrate after
removing these devices.  Add the trivial bit of final cleanup to
remove these entirely.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio: warn if host device rom can't be read

If the device rom can't be read, report an error to the
user. This alerts the user that the device has a bad
state that is causing rom read failure or option rom
loading has been disabled from the device boot menu
(among other reasons).

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio: Do not reattempt a failed rom read

During lazy rom loading, if rom read fails, and the
guest attempts a read again, vfio will again attempt it.
Add a boolean to prevent this. There could be a case where
a failed rom read might succeed the next time because of
a device reset or such, but it's best to exclude unpredictable
behavior

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio: Filter out bogus mappings

Since 57271d63 we now see spurious mappings with the upper bits set
if 64bit PCI BARs are sized while enabled.  The guest writes a mask
of 0xffffffff to the lower BAR to size it, then restores it, then
writes the same mask to the upper BAR resulting in a spurious BAR
mapping into the last 4G of the 64bit address space.  Most
architectures do not support or make use of the full 64bits address
space for PCI BARs, so we filter out mappings with the high bit set.
Long term, we probably need to think about vfio telling us the
address width limitations of the IOMMU.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
vfio-pci: Fail initfn on DMA mapping errors

The vfio-pci initfn will currently succeed even if DMA mappings fail.
A typical reason for failure is if the user does not have sufficient
privilege to lock all the memory for the guest.  In this case, the
device gets attached, but can only access a portion of guest memory
and is extremely unlikely to work.

DMA mappings are done via a MemoryListener, which provides no direct
error return path.  We therefore stuff the errno into our container
structure and check for error after registration completes.  We can
also test for mapping errors during runtime, but our only option for
resolution at that point is to kill the guest with a hw_error.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
kvm: initialize qemu_host_page_size

There is a HOST_PAGE_ALIGN macro which makes sense for KVM accelerator
but it uses qemu_host_page_size/qemu_host_page_mask which initialized
for TCG only.

This moves qemu_host_page_size/qemu_host_page_mask initialization from
TCG's page_init() and adds a call for it from kvm_init().

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio: fix mapping of MSIX bar

VFIO virtualizes MSIX table for the guest but not mapping the part of
a BAR which contains an MSIX table. Since vfio_mmap_bar() mmaps chunks
before and after the MSIX table, they have to be aligned to the host
page size which may be TARGET_PAGE_MASK (4K) or 64K in case of PPC64.

This fixes boundaries calculations to use the real host page size.

Without the patch, the chunk before MSIX table may overlap with the MSIX
table and mmap will fail in the host kernel. The result will be serious
slowdown as the whole BAR will be emulated by QEMU.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio: correct debug macro typo

Change to DEBUG_VFIO in vfio_msi_interrupt() for debug
messages to get printed

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
address_space_translate: do not cross page boundaries

The following commit:

commit 149f54b53b7666a3facd45e86eece60ce7d3b114
Author: Paolo Bonzini <pbonzini@redhat.com>
Date:   Fri May 24 12:59:37 2013 +0200

    memory: add address_space_translate

breaks Xen support in QEMU, in particular the Xen mapcache. The effect
is that one Windows XP installation out of ten would end up with BSOD.

The reason is that after this commit l in address_space_rw can span a
page boundary, however qemu_get_ram_ptr still calls xen_map_cache asking
to map a single page (if block->offset == 0).

Fix the issue by reverting to the previous behaviour: do not return a
length from address_space_translate_internal that can span a page
boundary.

Also in address_space_translate do not ignore the length returned by
address_space_translate_internal.

This patch should be backported to QEMU 1.6.x.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Anthony Perard <anthony.perard@citrix.com>
Tested-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-stable@nongnu.org
Merge remote-tracking branch 'remotes/sstabellini/xen-140130' into staging

* remotes/sstabellini/xen-140130:
  address_space_translate: do not cross page boundaries

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Merge remote-tracking branch 'remotes/awilliam/tags/vfio-pci-for-qemu-20140128.0' into staging

vfio-pci updates include:
 - Destroy MemoryRegions on device teardown
 - Print warnings around PCI option ROM failures
 - Skip bogus mappings from 64bit BAR sizing
 - Act on DMA mapping failures
 - Fix alignment to avoid MSI-X table mapping
 - Fix debug macro typo

# gpg: Signature made Tue 28 Jan 2014 15:27:47 GMT using RSA key ID 3BB08B22
# gpg: Can't check signature: public key not found

* remotes/awilliam/tags/vfio-pci-for-qemu-20140128.0:
  vfio: correct debug macro typo
  vfio: fix mapping of MSIX bar
  kvm: initialize qemu_host_page_size
  vfio-pci: Fail initfn on DMA mapping errors
  vfio: Filter out bogus mappings
  vfio: Do not reattempt a failed rom read
  vfio: warn if host device rom can't be read
  vfio: Destroy memory regions

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>