With this change, a FlatView can be used even after a concurrent
update has replaced it. Because we do not yet have RCU, we use a
mutex to protect the small critical sections that read/write the
as->current_map pointer. Accesses to the FlatView can be done
outside the mutex.
If a MemoryRegion will be used after the FlatView is unref-ed (or after
a MemoryListener callback is returned), a reference has to be added to
that MemoryRegion. memory_region_find already does it for the region
that it returns. The same will be done for address_space_translate
as soon as the dispatch tree is also converted to RCU-style.
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This is the first step towards converting as->current_map to
RCU-style updates, where the FlatView updates run concurrently
with uses of an old FlatView.
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We will soon require accesses to as->current_map to be placed under
a lock (with reference counting so as to keep the critical section
small). To simplify this change, always fetch as->current_map into
a local variable and access it through that variable.
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add ref/unref calls at the following places:
- places where memory regions are stashed by a listener and
used outside the BQL (including in Xen or KVM).
- memory_region_find callsites
- creation of aliases and containers (only the aliased/contained
region gets a reference to avoid loops)
- around calls to del_subregion/add_subregion, where the region
could disappear after the first call
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This new API will avoid having too many memory_region_ref/unref
in paths that currently use memory_region_find.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Whenever memory regions are accessed outside the BQL, they need to be
preserved against hot-unplug. MemoryRegions actually do not have their
own reference count; they piggyback on a QOM object, their "owner".
The owner is set at creation time, and there is a function to retrieve
the owner.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The current ioport dispatcher is a complex beast, mostly due to the
need to deal with old portio interface users. But we can overcome it
without converting all portio users by embedding the required base
address of a MemoryRegionPortio access into that data structure. That
removes the need to have the additional MemoryRegionIORange structure
in the loop on every access.
To handle old portio memory ops, we simply install dispatching handlers
for portio memory regions when registering them with the memory core.
This removes the need for the old_portio field.
We can drop the additional aliasing of ioport regions and also the
special address space listener. cpu_in and cpu_out now simply call
address_space_read/write. And we can concentrate portio handling in a
single source file.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use it for all targets, but be careful not to pass invalid CPUState.
cpu_single_env can be NULL, e.g. on Xen.
Signed-off-by: Andreas Färber <afaerber@suse.de>
These 4 replicated lines set properties of fr that are constant over
the course of the function. Factor out their repeated setting (and also
guards against them being set multiple times in the loop below).
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These comments were a little difficult to read. First one had
incorrect parenthesis. The part about attributes changing is
really applicable to the region being 'in both' rather than 'in
new'
Second comment has an obscure parenthetic about 'Logging may have
changed'. Made clearer, as this if is supposed to handle the case where
the memory region is unchanged (with the notable exception re logging).
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The "info mtree" command in QEMU console prints only "memory" and "I/O"
address spaces while there are actually a lot more other AddressSpace
structs created by PCI and VIO devices. Those devices do not normally
have names and therefore not present in "info mtree" output.
The patch fixes this.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
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>
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>
This will be used to split 8-byte access down to two four-byte accesses.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The memory API is able to use smaller/wider accesses than requested,
match that in memory_region_access_valid. Of course, the accepts
callback is still free to reject those accesses.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We'll use it to implement address_space_access_valid.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This allows to remove the checks on section->readonly. Simply,
write accesses to ROM will not be considered "direct" and will
go through mr->ops without any special intervention.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This provides the basics for detecting accesses to unassigned memory
as soon as they happen, and also for a simple implementation of
address_space_access_valid.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Even a new address space might have a non-empty FlatView. In order
to initialize it properly, address_space_init should (a) call
memory_region_transaction_commit after the address space is inserted
into the list; (b) force memory_region_transaction_commit to do something.
This bug was latent so far because all address spaces started empty, including
the PCI address space where the bus master region is initially disabled.
However, the target address space of an IOMMU is usually rooted at
get_system_memory(), which might not be empty at the time the IOMMU is created.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A couple of fields were left uninitialized. This was not observed earlier
because all address spaces were statically allocated. Also free allocation
for those fields.
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>
Since this is a MemoryListener operation, it only makes sense
on an AddressSpace granularity.
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
"Readable" is a very unfortunate name for this flag because even a
rom_device region will always be readable from the guest POV. What
differs is the mapping, just like the comments had to explain already.
Also, readable could currently be understood as being a generic region
flag, but it only applies to rom_device regions.
So rename the flag and the function to modify it after the original term
"ROMD" which could also be interpreted as "ROM direct", i.e. ROM mode
with direct access. In any case, the scope of the flag is clearer now.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
memory_region_find() is similar to registering a MemoryListener and
checking for the MemoryRegionSections that come from a particular
region. There is no reason for this to be limited to a root memory
region.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A memory size of zero is invalid, and so that edge condition
does not occur.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
We had two copies of a ffs function for longs with subtly different
semantics and, for the one in bitops.h, a confusing name: the result
was off-by-one compared to the library function ffsl.
Unify the functions into one, and solve the name problem by calling
the 0-based functions "bitops_ctzl" and "bitops_ctol" respectively.
This also fixes the build on platforms with ffsl, including Mac OS X
and Windows.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Andreas Färber <afaerber@suse.de>
Tested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Cirrus is triggering this, e.g. during Win2k boot: Changes only on
disabled regions require no topology update when transaction depth drops
to 0 again.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
The memory core drops regions that are hidden by another region (for example,
during BAR sizing), but it doesn't do so correctly if the lower address of the
existing range is below the lower address of the new range.
Example (qemu-system-mips -M malta -kernel vmlinux-2.6.32-5-4kc-malta
-append "console=ttyS0" -nographic -vga cirrus):
Existing range: 10000000-107fffff
New range: 100a0000-100bffff
Correct behaviour: drop new range
Incorrect behaviour: add new range
Fix by taking this case into account (previously we only considered
equal lower boundaries).
Tested-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
target_phys_addr_t is unwieldly, violates the C standard (_t suffixes are
reserved) and its purpose doesn't match the name (most target_phys_addr_t
addresses are not target specific). Replace it with a finger-friendly,
standards conformant hwaddr.
Outstanding patchsets can be fixed up with the command
git rebase -i --exec 'find -name "*.[ch]"
| xargs s/target_phys_addr_t/hwaddr/g' origin
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
* qemu-kvm/memory/urgent:
memory: abort if a memory region is destroyed during a transaction
i440fx: avoid destroying memory regions within a transaction
memory: Make eventfd adhere to device endianness
Currently we use a global radix tree to dispatch memory access. This only
works with a single address space; to support multiple address spaces we
make the radix tree a member of AddressSpace (via an intermediate structure
AddressSpaceDispatch to avoid exposing too many internals).
A side effect is that address_space_io also gains a dispatch table. When
we remove all the pre-memory-API I/O registrations, we can use that for
dispatching I/O and get rid of the original I/O dispatch.
Signed-off-by: Avi Kivity <avi@redhat.com>
Using the AddressSpace type reduces confusion, as you can't accidentally
supply the MemoryRegion you're interested in.
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
With this change, memory.c no longer knows anything about special address
spaces, so it is prepared for AddressSpace based DMA.
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Instead of calling a global function on coalesced mmio changes, which
routes the call to kvm if enabled, add coalesced mmio hooks to
MemoryListener and make kvm use that instead.
The motivation is support for multiple address spaces (which means we
we need to filter the call on the right address space) but the result
is cleaner as well.
Signed-off-by: Avi Kivity <avi@redhat.com>
