The restrictions here (which are checked at pre-plug time) are PAPR
specific, rather than being inherent to the NVDIMM devices. Adjust the
error messages to be clearer about this.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The pseries machine does not support NVDIMM modules without label.
Attempting to do so, even if the overall block size is aligned with
256MB, will seg fault the guest kernel during NVDIMM probe. This
can be avoided by forcing 'label-size' to always be present for
sPAPR NVDIMMs.
The verification was put before the alignment check because the
presence of label-size affects the alignment calculation, so
it's not optimal to warn the user about an alignment error,
then about the lack of label-size, then about a new alignment
error when the user sets a label-size.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20200413203628.31636-1-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Fixes Coverity issue,
CID 1419883: Error handling issues (CHECKED_RETURN)
Calling "qemu_uuid_parse" without checking return value
nvdimm_set_uuid() already verifies if the user provided uuid is valid or
not. So, need to check for the validity during pre-plug validation again.
As this a false positive in this case, assert if not valid to be safe.
Also, error_abort if QOM accessor encounters error while fetching the uuid
property.
Reported-by: Coverity (CID 1419883)
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Message-Id: <158281096564.89540.4507375445765515529.stgit@lep8c.aus.stglabs.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This patch implements few of the necessary hcalls for the nvdimm support.
PAPR semantics is such that each NVDIMM device is comprising of multiple
SCM(Storage Class Memory) blocks. The guest requests the hypervisor to
bind each of the SCM blocks of the NVDIMM device using hcalls. There can
be SCM block unbind requests in case of driver errors or unplug(not
supported now) use cases. The NVDIMM label read/writes are done through
hcalls.
Since each virtual NVDIMM device is divided into multiple SCM blocks,
the bind, unbind, and queries using hcalls on those blocks can come
independently. This doesn't fit well into the qemu device semantics,
where the map/unmap are done at the (whole)device/object level granularity.
The patch doesnt actually bind/unbind on hcalls but let it happen at the
device_add/del phase itself instead.
The guest kernel makes bind/unbind requests for the virtual NVDIMM device
at the region level granularity. Without interleaving, each virtual NVDIMM
device is presented as a separate guest physical address range. So, there
is no way a partial bind/unbind request can come for the vNVDIMM in a
hcall for a subset of SCM blocks of a virtual NVDIMM. Hence it is safe to
do bind/unbind everything during the device_add/del.
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Message-Id: <158131059899.2897.11515211602702956854.stgit@lep8c.aus.stglabs.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Add support for NVDIMM devices for sPAPR. Piggyback on existing nvdimm
device interface in QEMU to support virtual NVDIMM devices for Power.
Create the required DT entries for the device (some entries have
dummy values right now).
The patch creates the required DT node and sends a hotplug
interrupt to the guest. Guest is expected to undertake the normal
DR resource add path in response and start issuing PAPR SCM hcalls.
The device support is verified based on the machine version unlike x86.
This is how it can be used ..
Ex :
For coldplug, the device to be added in qemu command line as shown below
-object memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/tmp/nvdimm0,share=yes,size=1073872896
-device nvdimm,label-size=128k,uuid=75a3cdd7-6a2f-4791-8d15-fe0a920e8e9e,memdev=memnvdimm0,id=nvdimm0,slot=0
For hotplug, the device to be added from monitor as below
object_add memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/tmp/nvdimm0,share=yes,size=1073872896
device_add nvdimm,label-size=128k,uuid=75a3cdd7-6a2f-4791-8d15-fe0a920e8e9e,memdev=memnvdimm0,id=nvdimm0,slot=0
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
[Early implementation]
Message-Id: <158131058078.2897.12767731856697459923.stgit@lep8c.aus.stglabs.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
David Gibson
Daniel Henrique Barboza
Shivaprasad G Bhat