fix -net user checks by reordering checks

reorder slirp config options. first check the dns-server-address,
then check the first-dhcp-address. the original code was comparing
the first-dhcp-address with the default dns-server-address, not
the configured dns-server-address.

Signed-off-by: Bas van Sisseren <bas@quarantainenet.nl>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
make user networking hostfwd work with restrict=y

This patch allows the hostfwd option to override the restrict=y setting in
the user network stack, as explicitly stated in the documentation on the
restrict option:

     restrict=on|off
         If this option is enabled, the guest will be isolated, i.e. it
         will not be able to contact the host and no guest IP packets
         will be routed over the host to the outside. This option does
         not affect any explicitly set forwarding rules.

Qemu bug tracker:
https://bugs.launchpad.net/qemu/+bug/829455

Signed-off-by: Gertjan Halkes <qemu@ghalkes.nl>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
exec.c: address_space_translate: handle access to addr 0 of 2^64 sized region

The memory API allows a MemoryRegion's size to be 2^64, as a special
case (otherwise the size always fits in a 64 bit integer). This meant
that attempts to access address zero in a 2^64 sized region would
assert in address_space_translate():

  #3  0x00007ffff3e4d192 in __GI___assert_fail#(assertion=0x555555a43f32
    "!a.hi", file=0x555555a43ef0 "include/qemu/int128.h", line=18,
    function=0x555555a4439f "int128_get64") at assert.c:103
  #4  0x0000555555877642 in int128_get64 (a=...)
    at include/qemu/int128.h:18
  #5  0x00005555558782f2 in address_space_translate (as=0x55555668d140,
   /addr=0, xlat=0x7fffafac9918, plen=0x7fffafac9920, is_write=false)
    at exec.c:221

Fix this by doing the 'min' operation in 128 bit arithmetic
rather than 64 bit arithmetic (we know the result of the 'min'
definitely fits in 64 bits because one of the inputs did).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
memory: Introduce address_space_lookup_region

This introduces a wrapper for phys_page_find (before we complicate
address_space_translate with IOMMU translation).  This function will
also encapsulate locking and reference counting when we introduce
BQL-free dispatching.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
memory: move private types to exec.c

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
exec: Allow unaligned address_space_rw

This will be needed for some corner cases with para-virtual I/O ports.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
exec: Resolve subpages in one step except for IOTLB fills

Except for the case of setting the IOTLB entry in TCG mode, we can avoid
the subpage dispatching handlers and do the resolution directly on
address_space_lookup_region. An IOTLB entry describes a full page, not
only the region that the first access to a sub-divided page may return.

This patch therefore introduces a special translation function,
address_space_translate_for_iotlb, that avoids the subpage resolutions.
In contrast, callers of the existing address_space_translate service
will now always receive the terminal memory region section. This will be
important for breaking the BQL and for enabling unaligned memory region.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
exec: Implement subpage_read/write via address_space_rw

This will allow to add support for unaligned memory regions: the subpage
container region can activate unaligned support unconditionally because
the read/write handler will now ensure that accesses are split as
required by calling address_space_rw. We can furthermore drop the
special handling of RAM subpages, address_space_rw takes care of this
already.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
exec: return MemoryRegion from address_space_translate

Only address_space_translate_for_iotlb needs to return the section.
Every caller of address_space_translate now uses only section->mr,
return it directly.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Revert "memory: limit sections in the radix tree to the actual address space size"

This reverts commit 86a8623692b1b559a419a92eb8b6897c221bca74.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Revert "s390x: reduce TARGET_PHYS_ADDR_SPACE_BITS to 62"

This reverts commit 311f83ca08c011b048c063c2fd3038a8957970bc.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
exec: reorganize mem_add to match Int128 version

When adding support for 2^64-byte sections, we will have to change
the structure of mem_add to avoid failures in int128_get64.
Reorganize the code now before introducing Int128.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
memory: make section size a 128-bit integer

So far, the size of all regions passed to listeners could fit in 64 bits,
because artificial regions (containers and aliases) are eliminated by
the memory core, leaving only device regions which have reasonable sizes

An IOMMU however cannot be eliminated by the memory core, and may have
an artificial size, hence we may need 65 bits to represent its size.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
memory: iommu support

Add a new memory region type that translates addresses it is given,
then forwards them to a target address space.  This is similar to
an alias, except that the mapping is more flexible than a linear
translation and trucation, and also less efficient since the
translation happens at runtime.

The implementation uses an AddressSpace mapping the target region to
avoid hierarchical dispatch all the way to the resolved region; only
iommu regions are looked up dynamically.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
[Modified to put translation in address_space_translate; assume
 IOMMUs are not reachable from TCG. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
memory: Add iommu map/unmap notifiers

This patch adds a NotifierList to MemoryRegions which represent IOMMUs
allowing other parts of the code to register interest in mappings or
unmappings from the IOMMU.  All IOMMU implementations will need to call
memory_region_notify_iommu() to inform those waiting on the notifier list,
whenever an IOMMU mapping is made or removed.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
vfio: abort if an emulated iommu is used

vfio doesn't support guest iommus yet, indicate it to the user
by gently depositing a core on their disk.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
spapr: convert TCE API to use an opaque type

The TCE table is currently returned as a DMAContext, and non-type-safe
APIs are called later passing back the DMAContext.  Since we want to move
away from DMAContext, use an opaque type instead, and add an accessor
to retrieve the DMAContext from it.

Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
spapr: make IOMMU translation go through IOMMUTLBEntry

The next step is to introduce the translation code that will be used for
IOMMU MemoryRegions, but still do the actual translation in a DMAContext.

Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
spapr: use memory core for iommu support

Now we can stop using a "translating" DMAContext, but we do not yet modify
the sPAPRTCETable users to get an AddressSpace; they keep using the table
via a DMAContext.

Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
dma: eliminate old-style IOMMU support

The translate function in the DMAContext is now always NULL.
Remove every reference to it.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>