We used to check that the memory region size is multiples of the overall
requested address alignment for the device memory address.
We removed that check, because there are cases (i.e., hv-balloon) where
devices unconditionally request an address alignment that has a very large
alignment (i.e., 32 GiB), but the actual memory device size might not be
multiples of that alignment.
However, this change:
(a) allows for some practically impossible DIMM sizes, like "1GB+1 byte".
(b) allows for DIMMs that partially cover hugetlb pages, previously
reported in [1].
Both scenarios don't make any sense: we might even waste memory.
So let's reintroduce that check, but only check that the
memory region size is multiples of the memory region alignment (i.e.,
page size, huge page size), but not any additional memory device
requirements communicated using md->get_min_alignment().
The following examples now fail again as expected:
(a) 1M with 2M THP
qemu-system-x86_64 -m 4g,maxmem=16g,slots=1 -S -nodefaults -nographic \
-object memory-backend-ram,id=mem1,size=1M \
-device pc-dimm,id=dimm1,memdev=mem1
-> backend memory size must be multiple of 0x200000
(b) 1G+1byte
qemu-system-x86_64 -m 4g,maxmem=16g,slots=1 -S -nodefaults -nographic \
-object memory-backend-ram,id=mem1,size=1073741825B \
-device pc-dimm,id=dimm1,memdev=mem1
-> backend memory size must be multiple of 0x200000
(c) Unliagned hugetlb size (2M)
qemu-system-x86_64 -m 4g,maxmem=16g,slots=1 -S -nodefaults -nographic \
-object memory-backend-file,id=mem1,mem-path=/dev/hugepages/tmp,size=511M \
-device pc-dimm,id=dimm1,memdev=mem1
backend memory size must be multiple of 0x200000
(d) Unliagned hugetlb size (1G)
qemu-system-x86_64 -m 4g,maxmem=16g,slots=1 -S -nodefaults -nographic \
-object memory-backend-file,id=mem1,mem-path=/dev/hugepages1G/tmp,size=2047M \
-device pc-dimm,id=dimm1,memdev=mem1
-> backend memory size must be multiple of 0x40000000
Note that this fix depends on a hv-balloon change to communicate its
additional alignment requirements using get_min_alignment() instead of
through the memory region.
[1] https://lkml.kernel.org/r/f77d641d500324525ac036fe1827b3070de75fc1.1701088320.git.mprivozn@redhat.com
Message-ID: <20240117135554.787344-3-david@redhat.com>
Reported-by: Zhenyu Zhang <zhenyzha@redhat.com>
Reported-by: Michal Privoznik <mprivozn@redhat.com>
Fixes: eb1b7c4bd4 ("memory-device: Drop size alignment check")
Tested-by: Zhenyu Zhang <zhenyzha@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Fixes: 6c1b28e9e4 "memory-device: Support empty memory devices"
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
There is no strong requirement that the size has to be multiples of the
requested alignment, let's drop it. This is a preparation for hv-baloon.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Let's support empty memory devices -- memory devices that don't have a
memory device region in the current configuration. hv-balloon with an
optional memdev is the primary use case.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
We want to support memory devices that can automatically decide how many
memslots they will use. In the worst case, they have to use a single
memslot.
The target use cases are virtio-mem and the hyper-v balloon.
Let's calculate a reasonable limit such a memory device may use, and
instruct the device to make a decision based on that limit. Use a simple
heuristic that considers:
* A memslot soft-limit for all memory devices of 256; also, to not
consume too many memslots -- which could harm performance.
* Actually still free and unreserved memslots
* The percentage of the remaining device memory region that memory device
will occupy.
Further, while we properly check before plugging a memory device whether
there still is are free memslots, we have other memslot consumers (such as
boot memory, PCI BARs) that don't perform any checks and might dynamically
consume memslots without any prior reservation. So we might succeed in
plugging a memory device, but once we dynamically map a PCI BAR we would
be in trouble. Doing accounting / reservation / checks for all such
users is problematic (e.g., sometimes we might temporarily split boot
memory into two memslots, triggered by the BIOS).
We use the historic magic memslot number of 509 as orientation to when
supporting 256 memory devices -> memslots (leaving 253 for boot memory and
other devices) has been proven to work reliable. We'll fallback to
suggesting a single memslot if we don't have at least 509 total memslots.
Plugging vhost devices with less than 509 memslots available while we
have memory devices plugged that consume multiple memslots due to
automatic decisions can be problematic. Most configurations might just fail
due to "limit < used + reserved", however, it can also happen that these
memory devices would suddenly consume memslots that would actually be
required by other memslot consumers (boot, PCI BARs) later. Note that this
has always been sketchy with vhost devices that support only a small number
of memslots; but we don't want to make it any worse.So let's keep it simple
and simply reject plugging such vhost devices in such a configuration.
Eventually, all vhost devices that want to be fully compatible with such
memory devices should support a decent number of memslots (>= 509).
Message-ID: <20230926185738.277351-13-david@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
We want to support memory devices that have a dynamically managed memory
region container as device memory region. This device memory region maps
multiple RAM memory subregions (e.g., aliases to the same RAM memory
region), whereby these subregions can be (un)mapped on demand.
Each RAM subregion will consume a memslot in KVM and vhost, resulting in
such a new device consuming memslots dynamically, and initially usually
0. We already track the number of used vs. required memslots for all
memslots. From that, we can derive the number of reserved memslots that
must not be used otherwise.
The target use case is virtio-mem and the hyper-v balloon, which will
dynamically map aliases to RAM memory region into their device memory
region container.
Properly document what's supported and what's not and extend the vhost
memslot check accordingly.
Message-ID: <20230926185738.277351-10-david@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's track how many memslots are required by plugged memory devices and
how many are currently actually getting used by plugged memory
devices.
"required - used" is the number of reserved memslots. For now, the number
of used and required memslots is always equal, and there are no
reservations. This is a preparation for memory devices that want to
dynamically consume memslots after initially specifying how many they
require -- where we'll end up with reserved memslots.
To track the number of used memslots, create a new address space for
our device memory and register a memory listener (add/remove) for that
address space.
Message-ID: <20230926185738.277351-9-david@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
We want to support memory devices that have a memory region container as
device memory region that maps multiple RAM memory regions. Let's start
by supporting memory devices that statically map multiple RAM memory
regions and, thereby, consume multiple memslots.
We already have one device that uses a container as device memory region:
NVDIMMs. However, a NVDIMM always ends up consuming exactly one memslot.
Let's add support for that by asking the memory device via a new
callback how many memslots it requires.
Message-ID: <20230926185738.277351-7-david@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's return the number of free slots instead of only checking if there
is a free slot. Required to support memory devices that consume multiple
memslots.
This is a preparation for memory devices that consume multiple memslots.
Message-ID: <20230926185738.277351-6-david@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's return the number of free slots instead of only checking if there
is a free slot. While at it, check all address spaces, which will also
consider SMM under x86 correctly.
This is a preparation for memory devices that consume multiple memslots.
Message-ID: <20230926185738.277351-5-david@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's avoid iterating over all devices and simply track it in the
DeviceMemoryState.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20230623124553.400585-11-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's move memory_device_check_addable() and basic checks out of
memory_device_get_free_addr() directly into memory_device_pre_plug().
Separating basic checks from address assignment is cleaner and
prepares for further changes.
As all memory device users now use memory_devices_init(), and that
function enforces that the size is 0, we can drop the check for an empty
region.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20230623124553.400585-10-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's intrduce a new helper that we will use to replace existing memory
device setup code during machine initialization. We'll enforce that the
size has to be > 0.
Once all machines were converted, we'll only allocate ms->device_memory
if the size > 0.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20230623124553.400585-3-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's unify the error messages, such that we can simply stop allocating
ms->device_memory if the size would be 0 (and there are no memory
devices ever).
The case of "not supported by the machine" should barely pop up either
way: if the machine doesn't support memory devices, it usually doesn't
call the pre_plug handler ...
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20230623124553.400585-2-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
This had been pulled in via qemu/plugin.h from hw/core/cpu.h,
but that will be removed.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230310195252.210956-5-richard.henderson@linaro.org>
[AJB: add various additional cases shown by CI]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230315174331.2959-15-alex.bennee@linaro.org>
Reviewed-by: Emilio Cota <cota@braap.org>
These cases require a bit more thought to review; in each case, the
code was appending to a list, but not with a FOOList **tail variable.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210113221013.390592-6-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Flawed change to qmp_guest_network_get_interfaces() dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Add a callback that can be used to express additional alignment
requirements (exceeding the ones from the memory region).
Will be used by virtio-mem to express special alignment requirements due
to manually configured, big block sizes (e.g., 1GB with an ordinary
memory-backend-ram). This avoids failing later when realizing, because
auto-detection wasn't able to assign a properly aligned address.
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20201008083029.9504-6-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Let's warn instead of bailing out - the worst thing that can happen is
that we'll fail hot/coldplug later. The user got warned, and this should
be rare.
This will be necessary for memory devices with rather big (user-defined)
alignment requirements - say a virtio-mem device with a 2G block size -
which will become important, for example, when supporting vfio in the
future.
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20201008083029.9504-5-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
memory_device_get_free_addr() dereferences @errp when
memory_device_check_addable() fails. That's wrong; see the big
comment in error.h. Introduced in commit 1b6d6af21b "pc-dimm: factor
out capacity and slot checks into MemoryDevice".
No caller actually passes null.
Fix anyway: splice in a local Error *err, and error_propagate().
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20191204093625.14836-11-armbru@redhat.com>
The memory-device list built by memory_device_build_list is ordered by
its address, this means if the tmp range exceed the hinted range, all
the following range will not overlap with it.
And this won't change default pc-dimm mapping and address assignment stay
the same as before this change.
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190730003740.20694-3-richardw.yang@linux.intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
We are already at the last condition check.
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190730003740.20694-2-richardw.yang@linux.intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
In my "build everything" tree, changing hw/qdev-properties.h triggers
a recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
Many places including hw/qdev-properties.h (directly or via hw/qdev.h)
actually need only hw/qdev-core.h. Include hw/qdev-core.h there
instead.
hw/qdev.h is actually pointless: all it does is include hw/qdev-core.h
and hw/qdev-properties.h, which in turn includes hw/qdev-core.h.
Replace the remaining uses of hw/qdev.h by hw/qdev-properties.h.
While there, delete a few superfluous inclusions of hw/qdev-core.h.
Touching hw/qdev-properties.h now recompiles some 1200 objects.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20190812052359.30071-22-armbru@redhat.com>
Let's rewrite it properly using ranges. This fixes certain overflows that
are right now possible. E.g.
qemu-system-x86_64 -m 4G,slots=20,maxmem=40G -M pc \
-object memory-backend-file,id=mem1,share,mem-path=/dev/zero,size=2G
-device pc-dimm,memdev=mem1,id=dimm1,addr=-0x40000000
Now properly errors out instead of succeeding. (Note that qapi
parsing of huge uint64_t values is broken and fixes are on the way)
"can't add memory device [0xffffffffa0000000:0x80000000], usable range for
memory devices [0x140000000:0xe00000000]"
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181214131043.25071-3-david@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Should not be a problem right now, but it could theoretically happen
in the future.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181023152306.3123-7-david@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Shorter and easier to read.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181023152306.3123-6-david@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Let's trace the address and the id of a memory device when
pre_plugging/plugging/unplugging succeeded.
Trace it when pre_plugging as well as when plugging, so we really know
when a specific address is actually used.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-17-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
With the new memory device functions in place, we can factor out
unplugging of memory devices completely.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-16-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
With the new memory device functions in place, we can factor out
plugging of memory devices completely.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-15-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
With all required memory device class functions in place, we can factor
out pre_plug handling of memory devices. Take proper care of errors. We
still have to carry along legacy_align required for pc compatibility
handling.
We will factor out tracing of the address separately in a follow-up
patch.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-14-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
There are no remaining users of get_region_size() except
memory_device_get_region_size() itself. We can make
memory_device_get_region_size() work directly on get_memory_region()
instead and drop get_region_size().
In addition, we can now use memory_device_get_region_size() in pc-dimm
code to implement get_plugged_size()"
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-12-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
We will factor out get_memory_region() from pc-dimm to memory device code
soon. Once that is done, get_region_size() can be implemented
generically and essentially be replaced by
memory_device_get_region_size (and work only on get_memory_region()).
We have some users of get_memory_region() (spapr and pc-dimm code) that are
only interested in the size. So let's rework them to use
memory_device_get_region_size() first, then we can factor out
get_memory_region() and eventually remove get_region_size() without
touching the same code multiple times.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-10-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Let's properly forward the errors, so errors from get_region_size() /
get_plugged_size() can be handled.
Users right now call both functions after the device has been realized,
which is will never fail, so it is fine to continue using error_abort.
While at it, remove a leftover error check (suggested by Igor).
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-8-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
While we rephrased most error messages, we missed these.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-6-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Handle id==NULL better and indicate that we are dealing with memory
devices.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-4-david@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
The "at" should actually be a "before".
if (new_addr < address_space_start)
-> "can't add memory ... before... $address_space_start"
So it looks similar to the other check
} else if ((new_addr + size) > address_space_end)
-> "can't add memory ... beyond..."
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-3-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
We're missing "x" after the leading 0.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-2-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
The start of the address space indicates which maximum alignment is
supported by our machine (e.g. ppc, x86 1GB). This is helpful to
catch fragmenting guest physical memory in strange fashions.
Right now we can crash QEMU by e.g. (there might be easier examples)
qemu-system-x86_64 -m 256M,maxmem=20G,slots=2 \
-object memory-backend-file,id=mem0,size=8192M,mem-path=/dev/zero,align=8192M \
-device pc-dimm,id=dimm1,memdev=mem0
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180607154705.6316-2-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Registering the memory region for migration has do be done by the owner.
There could be cases, where we don't want to migrate the memory.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-8-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Move the checks into memory_device_get_free_addr(). This will check
before doing any calculations if we have KVM/vhost slots left and if
the total region size would be exceeded.
Of course, while at it, make it independent of pc-dimm code.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-7-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
This mainly moves code, but does a handfull of optimizations:
- We pass the machine instead of the address space properties
- We check the hinted address directly and handle fragmented memory
better
- We make the search independent of pc-dimm
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-6-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
On the qmp level, we already have the concept of memory devices:
"query-memory-devices"
Right now, we only support NVDIMM and PCDIMM.
We want to map other devices later into the address space of the guest.
Such device could e.g. be virtio devices. These devices will have a
guest memory range assigned but won't be exposed via e.g. ACPI. We want
to make them look like memory device, but not glued to pc-dimm.
Especially, it will not always be possible to have TYPE_PC_DIMM as a parent
class (e.g. virtio devices). Let's use an interface instead. As a first
part, convert handling of
- qmp_pc_dimm_device_list
- get_plugged_memory_size
to our new model. plug/unplug stuff etc. will follow later.
A memory device will have to provide the following functions:
- get_addr(): Necessary, as the property "addr" can e.g. not be used for
virtio devices (already defined).
- get_plugged_size(): The amount this device offers to the guest as of
now.
- get_region_size(): Because this can later on be bigger than the
plugged size.
- fill_device_info(): Fill MemoryDeviceInfo, e.g. for qmp.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180423165126.15441-2-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
