hw/ppc: Constify VMState

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231221031652.119827-48-richard.henderson@linaro.org>

migration: Use vmstate_register_any()

This are the easiest cases, where we were already using
VMSTATE_INSTANCE_ID_ANY.

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintel

migration: Use vmstate_register_any()

This are the easiest cases, where we were already using
VMSTATE_INSTANCE_ID_ANY.

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231020090731.28701-3-quintela@redhat.com>

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migration: Use vmstate_register_any()

This are the easiest cases, where we were already using
VMSTATE_INSTANCE_ID_ANY.

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintel

migration: Use vmstate_register_any()

This are the easiest cases, where we were already using
VMSTATE_INSTANCE_ID_ANY.

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231020090731.28701-3-quintela@redhat.com>

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migration: Use vmstate_register_any()

This are the easiest cases, where we were already using
VMSTATE_INSTANCE_ID_ANY.

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintel

migration: Use vmstate_register_any()

This are the easiest cases, where we were already using
VMSTATE_INSTANCE_ID_ANY.

Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231020090731.28701-3-quintela@redhat.com>

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ppc: spelling fixes

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Cédric Le Goater <clg@kaod.org>

ppc: spelling fixes

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Cédric Le Goater <clg@kaod.org>

ppc: spelling fixes

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Cédric Le Goater <clg@kaod.org>

nvdimm: Reject writing label data to ROM instead of crashing QEMU

Currently, when using a true R/O NVDIMM (ROM memory backend) with a label
area, the VM can easily crash QEMU by trying to write to t

nvdimm: Reject writing label data to ROM instead of crashing QEMU

Currently, when using a true R/O NVDIMM (ROM memory backend) with a label
area, the VM can easily crash QEMU by trying to write to the label area,
because the ROM memory is mmap'ed without PROT_WRITE.

[root@vm-0 ~]# ndctl disable-region region0
disabled 1 region
[root@vm-0 ~]# ndctl zero-labels nmem0
-> QEMU segfaults

Let's remember whether we have a ROM memory backend and properly
reject the write request:

[root@vm-0 ~]# ndctl disable-region region0
disabled 1 region
[root@vm-0 ~]# ndctl zero-labels nmem0
zeroed 0 nmem

In comparison, on a system with a R/W NVDIMM:

[root@vm-0 ~]# ndctl disable-region region0
disabled 1 region
[root@vm-0 ~]# ndctl zero-labels nmem0
zeroed 1 nmem

For ACPI, just return "unsupported", like if no label exists. For spapr,
return "H_P2", similar to when no label area exists.

Could we rely on the "unarmed" property? Maybe, but it looks cleaner to
only disallow what certainly cannot work.

After all "unarmed=on" primarily means: cannot accept persistent writes. In
theory, there might be setups where devices with "unarmed=on" set could
be used to host non-persistent data (temporary files, system RAM, ...); for
example, in Linux, admins can overwrite the "readonly" setting and still
write to the device -- which will work as long as we're not using ROM.
Allowing writing label data in such configurations can make sense.

Message-ID: <20230906120503.359863-2-david@redhat.com>
Fixes: dbd730e85987 ("nvdimm: check -object memory-backend-file, readonly=on option")
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

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thread-pool: avoid passing the pool parameter every time

thread_pool_submit_aio() is always called on a pool taken from
qemu_get_current_aio_context(), and that is the only intended
use: each pool r

thread-pool: avoid passing the pool parameter every time

thread_pool_submit_aio() is always called on a pool taken from
qemu_get_current_aio_context(), and that is the only intended
use: each pool runs only in the same thread that is submitting
work to it, it can't run anywhere else.

Therefore simplify the thread_pool_submit* API and remove the
ThreadPool function parameter.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230203131731.851116-5-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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thread-pool: avoid passing the pool parameter every time

thread_pool_submit_aio() is always called on a pool taken from
qemu_get_current_aio_context(), and that is the only intended
use: each pool r

thread-pool: avoid passing the pool parameter every time

thread_pool_submit_aio() is always called on a pool taken from
qemu_get_current_aio_context(), and that is the only intended
use: each pool runs only in the same thread that is submitting
work to it, it can't run anywhere else.

Therefore simplify the thread_pool_submit* API and remove the
ThreadPool function parameter.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230203131731.851116-5-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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thread-pool: avoid passing the pool parameter every time

thread_pool_submit_aio() is always called on a pool taken from
qemu_get_current_aio_context(), and that is the only intended
use: each pool r

thread-pool: avoid passing the pool parameter every time

thread_pool_submit_aio() is always called on a pool taken from
qemu_get_current_aio_context(), and that is the only intended
use: each pool runs only in the same thread that is submitting
work to it, it can't run anywhere else.

Therefore simplify the thread_pool_submit* API and remove the
ThreadPool function parameter.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230203131731.851116-5-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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hw/ppc: check if spapr_drc_index() returns NULL in spapr_nvdimm.c

spapr_nvdimm_flush_completion_cb() and flush_worker_cb() are using the
DRC object returned by spapr_drc_index() without checking it

hw/ppc: check if spapr_drc_index() returns NULL in spapr_nvdimm.c

spapr_nvdimm_flush_completion_cb() and flush_worker_cb() are using the
DRC object returned by spapr_drc_index() without checking it for NULL.
In this case we would be dereferencing a NULL pointer when doing
SPAPR_NVDIMM(drc->dev) and PC_DIMM(drc->dev).

This can happen if, during a scm_flush(), the DRC object is wrongly
freed/released (e.g. a bug in another part of the code).
spapr_drc_index() would then return NULL in the callbacks.

Fixes: Coverity CID 1487108, 1487178
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20220409200856.283076-2-danielhb413@gmail.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

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hw/ppc: check if spapr_drc_index() returns NULL in spapr_nvdimm.c

spapr_nvdimm_flush_completion_cb() and flush_worker_cb() are using the
DRC object returned by spapr_drc_index() without checking it

hw/ppc: check if spapr_drc_index() returns NULL in spapr_nvdimm.c

spapr_nvdimm_flush_completion_cb() and flush_worker_cb() are using the
DRC object returned by spapr_drc_index() without checking it for NULL.
In this case we would be dereferencing a NULL pointer when doing
SPAPR_NVDIMM(drc->dev) and PC_DIMM(drc->dev).

This can happen if, during a scm_flush(), the DRC object is wrongly
freed/released (e.g. a bug in another part of the code).
spapr_drc_index() would then return NULL in the callbacks.

Fixes: Coverity CID 1487108, 1487178
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20220409200856.283076-2-danielhb413@gmail.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>

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spapr: nvdimm: Introduce spapr-nvdimm device

If the device backend is not persistent memory for the nvdimm, there is
need for explicit IO flushes on the backend to ensure persistence.

On SPAPR, the

spapr: nvdimm: Introduce spapr-nvdimm device

If the device backend is not persistent memory for the nvdimm, there is
need for explicit IO flushes on the backend to ensure persistence.

On SPAPR, the issue is addressed by adding a new hcall to request for
an explicit flush from the guest when the backend is not pmem. So, the
approach here is to convey when the hcall flush is required in a device
tree property. The guest once it knows the device backend is not pmem,
makes the hcall whenever flush is required.

To set the device tree property, a new PAPR specific device type inheriting
the nvdimm device is implemented. When the backend doesn't have pmem=on
the device tree property "ibm,hcall-flush-required" is set, and the guest
makes hcall H_SCM_FLUSH requesting for an explicit flush. The new device
has boolean property pmem-override which when "on" advertises the device
tree property even when pmem=on for the backend. The flush function
invokes the fdatasync or pmem_persist() based on the type of backend.

The vmstate structures are made part of the spapr-nvdimm device object.
The patch attempts to keep the migration compatibility between source and
destination while rejecting the incompatibles ones with failures.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <164396256092.109112.17933240273840803354.stgit@ltczzess4.aus.stglabs.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

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spapr: nvdimm: Implement H_SCM_FLUSH hcall

The patch adds support for the SCM flush hcall for the nvdimm devices.
To be available for exploitation by guest through the next patch. The
hcall is appli

spapr: nvdimm: Implement H_SCM_FLUSH hcall

The patch adds support for the SCM flush hcall for the nvdimm devices.
To be available for exploitation by guest through the next patch. The
hcall is applicable only for new SPAPR specific device class which is
also introduced in this patch.

The hcall expects the semantics such that the flush to return with
H_LONG_BUSY_ORDER_10_MSEC when the operation is expected to take longer
time along with a continue_token. The hcall to be called again by providing
the continue_token to get the status. So, all fresh requests are put into
a 'pending' list and flush worker is submitted to the thread pool. The
thread pool completion callbacks move the requests to 'completed' list,
which are cleaned up after collecting the return status for the guest
in subsequent hcall from the guest.

The semantics makes it necessary to preserve the continue_tokens and
their return status across migrations. So, the completed flush states
are forwarded to the destination and the pending ones are restarted
at the destination in post_load. The necessary nvdimm flush specific
vmstate structures are also introduced in this patch which are to be
saved in the new SPAPR specific nvdimm device to be introduced in the
following patch.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <164396254862.109112.16675611182159105748.stgit@ltczzess4.aus.stglabs.ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

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spapr: nvdimm: Fix the persistent-memory root node name in device tree

The FDT code is adding the pmem root node by name "persistent-memory"
which should have been "ibm,persistent-memory".

The linu

spapr: nvdimm: Fix the persistent-memory root node name in device tree

The FDT code is adding the pmem root node by name "persistent-memory"
which should have been "ibm,persistent-memory".

The linux fetches the device tree nodes by type and it has been working
correctly as the type is correct. If someone searches by its intended
name it would fail, so fix that.

Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Message-Id: <162204278956.219.9061511386011411578.stgit@cc493db1e665>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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spapr: nvdimm: Forward declare and move the definitions

The subsequent patches add definitions which tend to get
the compilation to cyclic dependency. So, prepare with
forward declarations, move the

spapr: nvdimm: Forward declare and move the definitions

The subsequent patches add definitions which tend to get
the compilation to cyclic dependency. So, prepare with
forward declarations, move the definitions and clean up.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Message-Id: <162133925415.610.11584121797866216417.stgit@4f1e6f2bd33e>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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ppc/spapr: Add support for implement support for H_SCM_HEALTH

Add support for H_SCM_HEALTH hcall described at [1] for spapr
nvdimms. This enables guest to detect the 'unarmed' status of a
specific s

ppc/spapr: Add support for implement support for H_SCM_HEALTH

Add support for H_SCM_HEALTH hcall described at [1] for spapr
nvdimms. This enables guest to detect the 'unarmed' status of a
specific spapr nvdimm identified by its DRC and if its unarmed, mark
the region backed by the nvdimm as read-only.

The patch adds h_scm_health() to handle the H_SCM_HEALTH hcall which
returns two 64-bit bitmaps (health bitmap, health bitmap mask) derived
from 'struct nvdimm->unarmed' member.

Linux kernel side changes to enable handling of 'unarmed' nvdimms for
ppc64 are proposed at [2].

References:
[1] "Hypercall Op-codes (hcalls)"
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/powerpc/papr_hcalls.rst#n220
[2] "powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe"
https://lore.kernel.org/linux-nvdimm/20210329113103.476760-1-vaibhav@linux.ibm.com/

Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Message-Id: <20210402102128.213943-1-vaibhav@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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ppc/spapr: cleanup -machine pseries,nvdimm=X handling

Since NVDIMM support was introduced on pseries machine,
it ignored machine's nvdimm=on|off option and effectively
was always enabled on machines

ppc/spapr: cleanup -machine pseries,nvdimm=X handling

Since NVDIMM support was introduced on pseries machine,
it ignored machine's nvdimm=on|off option and effectively
was always enabled on machines that support NVDIMM.
Later on commit
(28f5a716212 ppc/spapr_nvdimm: do not enable support with 'nvdimm=off')
makes QEMU error out in case user explicitly set 'nvdimm=off'
on CLI by peeking at machine_opts.

However that's a workaround and leaves 'nvdimms_state->is_enabled'
in inconsistent state (false) when it should be set true
by default.

Instead of using on machine_opts, set default to true for pseries
machine in initfn time. If user sets manually 'nvdimm=off'
it will overwrite default value to false and QEMU will error
as expected without need to peek into machine_opts.

That way pseries will have, nvdimm enabled by default and
will honor user provided 'nvdimm=on|off'.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20201208164606.4109134-1-imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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spapr: spapr_drc_attach() cannot fail

All users are passing &error_abort already. Document the fact
that spapr_drc_attach() should only be passed a free DRC, which
is supposedly the case if appropri

spapr: spapr_drc_attach() cannot fail

All users are passing &error_abort already. Document the fact
that spapr_drc_attach() should only be passed a free DRC, which
is supposedly the case if appropriate checking is done earlier.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201201113728.885700-5-groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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spapr: Do NVDIMM/PC-DIMM device hotplug sanity checks at pre-plug only

Pre-plug of a memory device, be it an NVDIMM or a PC-DIMM, ensures
that the memory slot is available and that addresses don't o

spapr: Do NVDIMM/PC-DIMM device hotplug sanity checks at pre-plug only

Pre-plug of a memory device, be it an NVDIMM or a PC-DIMM, ensures
that the memory slot is available and that addresses don't overlap
with existing memory regions. The corresponding DRCs in the LMB
and PMEM namespaces are thus necessarily attachable at plug time.

Pass &error_abort to spapr_drc_attach() in spapr_add_lmbs() and
spapr_add_nvdimm(). This allows to greatly simplify error handling
on the plug path.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201120234208.683521-3-groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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spapr: Simplify error handling in spapr_memory_plug()

As recommended in "qapi/error.h", add a bool return value to
spapr_add_lmbs() and spapr_add_nvdimm(), and use them instead
of local_err in spapr

spapr: Simplify error handling in spapr_memory_plug()

As recommended in "qapi/error.h", add a bool return value to
spapr_add_lmbs() and spapr_add_nvdimm(), and use them instead
of local_err in spapr_memory_plug().

This allows to get rid of the error propagation overhead.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <160309734178.2739814.3488437759887793902.stgit@bahia.lan>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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spapr: Move spapr_create_nvdimm_dr_connectors() to core machine code

The spapr_create_nvdimm_dr_connectors() function doesn't need to access
any internal details of the sPAPR NVDIMM implementation.

spapr: Move spapr_create_nvdimm_dr_connectors() to core machine code

The spapr_create_nvdimm_dr_connectors() function doesn't need to access
any internal details of the sPAPR NVDIMM implementation. Also, pretty
much like for the LMBs, only spapr_machine_init() is responsible for the
creation of DR connectors for NVDIMMs.

Make this clear by making this function static in hw/ppc/spapr.c.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <160249772183.757627.7396780936543977766.stgit@bahia.lan>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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spapr: Add a return value to spapr_nvdimm_validate()

As recommended in "qapi/error.h", return true on success and false on
failure. This allows to reduce error propagation overhead in the callers.

spapr: Add a return value to spapr_nvdimm_validate()

As recommended in "qapi/error.h", return true on success and false on
failure. This allows to reduce error propagation overhead in the callers.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200914123505.612812-13-groug@kaod.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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spapr: Add a return value to spapr_drc_attach()

As recommended in "qapi/error.h", return true on success and false on
failure. This allows to reduce error propagation overhead in the callers.

Signe

spapr: Add a return value to spapr_drc_attach()

As recommended in "qapi/error.h", return true on success and false on
failure. This allows to reduce error propagation overhead in the callers.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200914123505.612812-9-groug@kaod.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

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