This way, if we have several changes in a single transaction, we flush just
once.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Identical except that the second branch knows its not modifying an existing
subpage.
Signed-off-by: NAvi Kivity <avi@redhat.com>

If the first subpage installed in a page is RAM, then we install it as
a full page, instead of a subpage.  Fix by not special casing RAM.

The issue dates to commit db7b5426, which introduced subpages.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Use an expanding vector to store nodes.  Allocation is baroque to g_renew()
potentially invalidating pointers; this will be addressed later.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Instead of storing PhysPageDesc, store pointers to MemoryRegionSections.
The various offsets (phys_offset & ~TARGET_PAGE_MASK,
PHYS_OFFSET & TARGET_PAGE_MASK, region_offset) can all be synthesized
from the information in a MemoryRegionSection.  Adjust phys_page_find()
to synthesize a PhysPageDesc.

The upshot is that phys_map now contains uniform values, so it's easier
to generate and compress.

The end result is somewhat clumsy but this will be improved as we we
propagate MemoryRegionSections throughout the code instead of transforming
them to PhysPageDesc.

The MemoryRegionSection pointers are stored as uint16_t offsets in an
array.  This saves space (when we also compress node pointers) and is
more cache friendly.
Signed-off-by: NAvi Kivity <avi@redhat.com>

This lays the groundwork for storing leaf data in intermediate levels,
saving space.
Signed-off-by: NAvi Kivity <avi@redhat.com>

L1 and the lower levels in l1_phys_map are equivalent, except that L1 has
a different size, and is always allocated.  Simplify the code by removing
L1.  This leaves us with a tree composed solely of L2 tables, but that
problem can be renamed away later.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Instead of incrementally building the memory map, rebuild it every time.
This allows later simplification, since the code need not consider overlaying
a previous mapping.  It is also RCU friendly.

With large memory guests this can get expensive, since the operation is
O(mem size), but this will be optimized later.

As a side effect subpage and L2 leaks are fixed here.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Current memory listeners are incremental; that is, they are expected to
maintain their own state, and receive callbacks for changes to that state.

This patch adds support for stateless listeners; these work by receiving
a ->begin() callback (which tells them that new state is coming), a
sequence of ->region_add() and ->region_nop() callbacks, and then a
->commit() callback which signifies the end of the new state.  They should
ignore ->region_del() callbacks.
Signed-off-by: NAvi Kivity <avi@redhat.com>

The memory and I/O address spaces do different things, so split them into
two memory listeners.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Ignore any regions not belonging to a specified address space.
Signed-off-by: NAvi Kivity <avi@redhat.com>

This transforms memory.c into a library which can then be unit tested
easily, by feeding it inputs and listening to its outputs.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

It can be derived from the MemoryRegion itself (which is why it is not
used there).
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Clarify the comment about tlb_flush()'s flush_global parameter,
so it is clearer what it does and why it is OK that the implementation
currently ignores it.
Reviewed-by: NAndreas F=C3=A4rber <afaerber@suse.de>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The virtio config area in PIO space is a bit special. The initial
header is little endian but the rest (device specific) is guest
native endian.

The PIO accessors for PCI on machines that don't have native IO ports
assume that all PIO is little endian, which works fine for everything
except the above.

A complicated way to fix it would be to split the BAR into two memory
regions with different endianess settings, but this isn't practical
to do, besides, the PIO code doesn't honor region endianness anyway
(I have a patch for that too but it isn't necessary at this stage).

So I decided to go for the quick fix instead which consists of
reverting the swap in virtio-pci in selected places, hoping that when
we eventually do a "v2" of the virtio protocols, we sort that out once
and for all using a fixed endian setting for everything.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>
[agraf: keep virtio in libhw and determine endianness through a
        helper function in exec.c]
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>

ARM still doesn't support 16GB buffers in 32-bit modes, replace the
16GB by 16MB in the comment.
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>

We no longer use any of the lower bits of a ram_addr, so we might as well
use them for the io table index.  This increases the number of potential
I/O handlers by a factor of 8.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Unlike ->readonly, ->readable is not inherited from aliase, so we can simply
query the memory region.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Replace with a MemoryRegion flag.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Now that all mmio goes through MemoryRegions, we can convert
io_mem_opaque to be a MemoryRegion pointer, and remove the thunks
that convert from old-style CPU{Read,Write}MemoryFunc to MemoryRegionOps.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Still internally using ram_addr.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Convert the fixed-address IO_MEM_RAM, IO_MEM_ROM, IO_MEM_UNASSIGNED,
and IO_MEM_NOTDIRTY io handlers to MemoryRegions.  These aren't real
regions, since they are never added to the memory hierarchy, but they
allow reuse of the dispatch functionality.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Its use of IO_MEM_ROM and friends will later cause #include loops; and it
is too large to merit inlining.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

The code sometimes uses range comparisons on io indexes (e.g.
index =< IO_MEM_ROM).  Avoid these as they make moving to objects harder.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

cpu_register_physical_memory_log() does not update region_offset
if a page was previously registered for the same address.  This
could cause mmio accesses going to the wrong place, by using the
old region_offset.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Acked-by: NAndreas Färber <afaerber@suse.de>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Currently mmio access goes directly to the io_mem_{read,write} arrays.
In preparation for eliminating them, add indirection via a function.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Instead of returning a PhysPageDesc pointer, return a temporary.
This lets us move away from actually storing PhysPageDesc's, and
instead sythesising them when needed.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Instead of doing device endianness compensation in cpu_register_io_memory(),
do it in the memory core.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

The getter is no longer used, so it is completely removed.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

As a step in moving live migration from RAMBlocks to MemoryRegions,
store the MemoryRegion in a RAMBlock.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Currently creating a memory region automatically registers it for
live migration.  This differs from other state (which is enumerated
in a VMStateDescription structure) and ties the live migration code
into the memory core.

Decouple the two by introducing a separate API, vmstate_register_ram(),
for registering a RAM block for migration.  Currently the same
implementation is reused, but later it can be moved into a separate list,
and registrations can be moved to VMStateDescription blocks.
Signed-off-by: NAvi Kivity <avi@redhat.com>

No longer used.
Signed-off-by: NAvi Kivity <avi@redhat.com>

No longer used.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Add an API that allows a client to observe changes in the global
memory map:
 - region added (possibly with logging enabled)
 - region removed (possibly with logging enabled)
 - logging started on a region
 - logging stopped on a region
 - global logging started
 - global logging removed

This API will eventually replace cpu_register_physical_memory_client().
Signed-off-by: NAvi Kivity <avi@redhat.com>

This will help avoid accidental usage.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Currently xen_ram_alloc() relies on ram_addr, which is going away.
Give it something else to use as a cookie.
Signed-off-by: NAvi Kivity <avi@redhat.com>

This fixes a common bug with initial region_offset value.
Usually, the pages are re-assigned afterwards, so the bug
has a very small effect on regular QEMU use flows.
Signed-off-by: NAlex Rozenman <Alex_Rozenman@mentor.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>