vfio-pci: Add support for MSI affinity

When MSI is accelerated through KVM the vectors are only programmed
when the guest first enables MSI support.  Subsequent writes to the
vector address or data fields are ignored.  Unfortunately that means
we're ignore updates done to adjust SMP affinity of the vectors.
MSI SMP affinity already works in non-KVM mode because the address
and data fields are read from their backing store on each interrupt.

This patch stores the MSIMessage programmed into KVM so that we can
determine when changes are made and update the routes.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio-pci: Test device reset capabilities

Not all resets are created equal.  PM reset is not very reliable,
especially for GPUs, so we might want to opt for a bus reset if a
standard reset will only do a D3hot->D0 transition.  We can also
use this to tell if the standard reset will do a bus reset (if
neither has_pm_reset or has_flr is probed, but the device still
supports reset).

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio-pci: Lazy PCI option ROM loading

During vfio-pci initfn, the device is not always in a state where the
option ROM can be read.  In the case of graphics cards, there's often
no per function reset, which means we have host driver state affecting
whether the option ROM is usable.  Ideally we want to move reading the
option ROM past any co-assigned device resets to the point where the
guest first tries to read the ROM itself.

To accomplish this, we switch the memory region for the option rom to
an I/O region rather than a memory mapped region.  This has the side
benefit that we don't waste KVM memory slots for a BAR where we don't
care about performance.  This also allows us to delay loading the ROM
from the device until the first read by the guest.  We then use the
PCI config space size of the ROM BAR when setting up the BAR through
QEMU PCI.

Another benefit of this approach is that previously when a user set
the ROM to a file using the romfile= option, we still probed VFIO for
the parameters of the ROM, which can result in dmesg errors about an
invalid ROM.  We now only probe VFIO to get the ROM contents if the
guest actually tries to read the ROM.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio-pci: Cleanup error_reports

Remove carriage returns and tweak formatting for error_reports.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio-pci: Implement PCI hot reset

Now that VFIO has a PCI hot reset interface, take advantage of it.
There are two modes that we need to consider.  The first is when only
one device within the set of devices affected is actually assigned to
the guest.  In this case the other devices are are just held by VFIO
for isolation and we can pretend they're not there, doing an entire
bus reset whenever the device reset callback is triggered.  Supporting
this case separately allows us to do the best reset we can do of the
device even if the device is hotplugged.

The second mode is when multiple affected devices are all exposed to
the guest.  In this case we can only do a hot reset when the entire
system is being reset.  However, this also allows us to track which
individual devices are affected by a reset and only do them once.

We split our reset function into pre- and post-reset helper functions
prioritize the types of device resets available to us, and create
separate _one vs _multi reset interfaces to handle the distinct cases
above.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
target-openrisc: Correct handling of page faults.

The result of (rw & 0) is always zero and therefore a logic false.
The whole comparison will therefore never be executed, it is a obvious bug,
we should use !(rw & 1) here.

Signed-off-by: Sebastian Macke <sebastian@macke.de>
Reviewed-by: Jia Liu <proljc@gmail.com>
target-openrisc: Removes a non-conforming behavior for the first page of the memory

Where *software* leaves 0x0000 - 0x2000 unmapped, the hardware should
still allow for this area to be mapped.

Signed-off-by: Sebastian Macke <sebastian@macke.de>
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Reviewed-by: Jia Liu <proljc@gmail.com>
vfio: Fix debug output for int128 values

Memory regions can easily be 2^64 byte long and therefore overflow
for just a bit but that is enough for int128_get64() to assert.

This takes care of debug printing of huge section sizes.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio-pci: Add dummy PCI ROM write accessor

Just to be sure we don't jump off any NULL pointer cliffs.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
vfio-pci: Fix endian issues in vfio_pci_size_rom()

VFIO is always little endian so do byte swapping of our mask on the
way in and byte swapping of the size on the way out.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
tcg: Use TCGMemOp for TCGLabelQemuLdst.opc

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-i386: Use TCGMemOp within qemu_ldst routines

Step one in the transition, with constants passed down from tcg_out_op.

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-i386: Tidy softmmu routines

Pass two TCGReg to tcg_out_tlb_load, rather than idx+args.

Move ldst_optimization routines just below tcg_out_tlb_load to avoid
the need for forward declarations.

Use TCGReg enum in preference to int where apprpriate.

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-i386: Remove "cb" output restriction from qemu_st8 for i386

Once we form a combined qemu_st_i32 opcode, we won't be able to
have separate constraints based on size.  This one is fairly easy
to work around, since eax is available as a scratch register.

When storing variable data, this tends to merely exchange one mov
for another.  E.g.

-:  mov    %esi,%ecx
...
-:  mov    %cl,(%edx)
+:  mov    %esi,%eax
+:  mov    %al,(%edx)

Where we do have a regression is when storing constant data, in which
we may load the constant into edi, when only ecx/ebx ought to be used.

The proper way to recover this regression is to allow constants as
arguments to qemu_st_i32, so that we never load the constant data into
a register at all, must less the wrong register.  TBD.

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-i386: Support new ldst opcodes

No support for helpers with non-default endianness yet,
but good enough to test the opcodes.

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-arm: Use TCGMemOp within qemu_ldst routines

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-arm: Convert to le/be ldst helpers

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-arm: Tidy variable naming convention in qemu_ld/st

s/addr_reg2/addrhi/
s/addr_reg/addrlo/
s/data_reg2/datahi/
s/data_reg/datalo/

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-arm: Convert to new ldst opcodes

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-arm: Improve GUEST_BASE qemu_ld/st

If we pull the code to emit the actual load/store into a subroutine,
we can share the reg+reg addressing mode code between softmmu and
usermode.  This lets us load GUEST_BASE into a temporary register
rather than attempting to add it piece-wise to the address.

Which lets us use movw+movt for armv7, rather than (up to) 4 adds.
Code size for pre-armv7 stays the same.

Signed-off-by: Richard Henderson <rth@twiddle.net>