pds_core: Rework teardown/setup flow to be more common

[ Upstream commit bc90fbe0c3182157d2be100a2f6c2edbb1820677 ]

Currently the teardown/setup flow for driver probe/remove is quite
a bit differen

pds_core: Rework teardown/setup flow to be more common

[ Upstream commit bc90fbe0c3182157d2be100a2f6c2edbb1820677 ]

Currently the teardown/setup flow for driver probe/remove is quite
a bit different from the reset flows in pdsc_fw_down()/pdsc_fw_up().
One key piece that's missing are the calls to pci_alloc_irq_vectors()
and pci_free_irq_vectors(). The pcie reset case is calling
pci_free_irq_vectors() on reset_prepare, but not calling the
corresponding pci_alloc_irq_vectors() on reset_done. This is causing
unexpected/unwanted interrupt behavior due to the adminq interrupt
being accidentally put into legacy interrupt mode. Also, the
pci_alloc_irq_vectors()/pci_free_irq_vectors() functions are being
called directly in probe/remove respectively.

Fix this inconsistency by making the following changes:
1. Always call pdsc_dev_init() in pdsc_setup(), which calls
pci_alloc_irq_vectors() and get rid of the now unused
pds_dev_reinit().
2. Always free/clear the pdsc->intr_info in pdsc_teardown()
since this structure will get re-alloced in pdsc_setup().
3. Move the calls of pci_free_irq_vectors() to pdsc_teardown()
since pci_alloc_irq_vectors() will always be called in
pdsc_setup()->pdsc_dev_init() for both the probe/remove and
reset flows.
4. Make sure to only create the debugfs "identity" entry when it
doesn't already exist, which it will in the reset case because
it's already been created in the initial call to pdsc_dev_init().

Fixes: ffa55858330f ("pds_core: implement pci reset handlers")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20240129234035.69802-7-brett.creeley@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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pds_core: Prevent race issues involving the adminq

[ Upstream commit 7e82a8745b951b1e794cc780d46f3fbee5e93447 ]

There are multiple paths that can result in using the pdsc's
adminq.

[1] pdsc_adminq

pds_core: Prevent race issues involving the adminq

[ Upstream commit 7e82a8745b951b1e794cc780d46f3fbee5e93447 ]

There are multiple paths that can result in using the pdsc's
adminq.

[1] pdsc_adminq_isr and the resulting work from queue_work(),
i.e. pdsc_work_thread()->pdsc_process_adminq()

[2] pdsc_adminq_post()

When the device goes through reset via PCIe reset and/or
a fw_down/fw_up cycle due to bad PCIe state or bad device
state the adminq is destroyed and recreated.

A NULL pointer dereference can happen if [1] or [2] happens
after the adminq is already destroyed.

In order to fix this, add some further state checks and
implement reference counting for adminq uses. Reference
counting was used because multiple threads can attempt to
access the adminq at the same time via [1] or [2]. Additionally,
multiple clients (i.e. pds-vfio-pci) can be using [2]
at the same time.

The adminq_refcnt is initialized to 1 when the adminq has been
allocated and is ready to use. Users/clients of the adminq
(i.e. [1] and [2]) will increment the refcnt when they are using
the adminq. When the driver goes into a fw_down cycle it will
set the PDSC_S_FW_DEAD bit and then wait for the adminq_refcnt
to hit 1. Setting the PDSC_S_FW_DEAD before waiting will prevent
any further adminq_refcnt increments. Waiting for the
adminq_refcnt to hit 1 allows for any current users of the adminq
to finish before the driver frees the adminq. Once the
adminq_refcnt hits 1 the driver clears the refcnt to signify that
the adminq is deleted and cannot be used. On the fw_up cycle the
driver will once again initialize the adminq_refcnt to 1 allowing
the adminq to be used again.

Fixes: 01ba61b55b20 ("pds_core: Add adminq processing and commands")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://lore.kernel.org/r/20240129234035.69802-5-brett.creeley@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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pds_core: implement pci reset handlers

[ Upstream commit ffa55858330f267beec995fc4f68098c91311c64 ]

Implement the callbacks for a nice PCI reset. These get called
when a user is nice enough to use

pds_core: implement pci reset handlers

[ Upstream commit ffa55858330f267beec995fc4f68098c91311c64 ]

Implement the callbacks for a nice PCI reset. These get called
when a user is nice enough to use the sysfs PCI reset entry, e.g.
echo 1 > /sys/bus/pci/devices/0000:2b:00.0/reset

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 7e82a8745b95 ("pds_core: Prevent race issues involving the adminq")
Signed-off-by: Sasha Levin <sashal@kernel.org>

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pds_core: Use struct pdsc for the pdsc_adminq_isr private data

[ Upstream commit 951705151e50f9022bc96ec8b3fd5697380b1df6 ]

The initial design for the adminq interrupt was done based
on client driv

pds_core: Use struct pdsc for the pdsc_adminq_isr private data

[ Upstream commit 951705151e50f9022bc96ec8b3fd5697380b1df6 ]

The initial design for the adminq interrupt was done based
on client drivers having their own adminq and adminq
interrupt. So, each client driver's adminq isr would use
their specific adminqcq for the private data struct. For the
time being the design has changed to only use a single
adminq for all clients. So, instead use the struct pdsc for
the private data to simplify things a bit.

This also has the benefit of not dereferencing the adminqcq
to access the pdsc struct when the PDSC_S_STOPPING_DRIVER bit
is set and the adminqcq has actually been cleared/freed.

Fixes: 01ba61b55b20 ("pds_core: Add adminq processing and commands")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://lore.kernel.org/r/20240129234035.69802-4-brett.creeley@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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pds_core: Cancel AQ work on teardown

[ Upstream commit d321067e2cfa4d5e45401a00912ca9da8d1af631 ]

There is a small window where pdsc_work_thread()
calls pdsc_process_adminq() and pdsc_process_admin

pds_core: Cancel AQ work on teardown

[ Upstream commit d321067e2cfa4d5e45401a00912ca9da8d1af631 ]

There is a small window where pdsc_work_thread()
calls pdsc_process_adminq() and pdsc_process_adminq()
passes the PDSC_S_STOPPING_DRIVER check and starts
to process adminq/notifyq work and then the driver
starts a fw_down cycle. This could cause some
undefined behavior if the notifyqcq/adminqcq are
free'd while pdsc_process_adminq() is running. Use
cancel_work_sync() on the adminqcq's work struct
to make sure any pending work items are cancelled
and any in progress work items are completed.

Also, make sure to not call cancel_work_sync() if
the work item has not be initialized. Without this,
traces will happen in cases where a reset fails and
teardown is called again or if reset fails and the
driver is removed.

Fixes: 01ba61b55b20 ("pds_core: Add adminq processing and commands")
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://lore.kernel.org/r/20240129234035.69802-3-brett.creeley@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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pds_core: no reset command for VF

The VF doesn't need to send a reset command, and in a PCI reset
scenario it might not have a valid IO space to write to anyway.

Fixes: 523847df1b37 ("pds_core: add

pds_core: no reset command for VF

The VF doesn't need to send a reset command, and in a PCI reset
scenario it might not have a valid IO space to write to anyway.

Fixes: 523847df1b37 ("pds_core: add devcmd device interfaces")
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230824161754.34264-4-shannon.nelson@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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pds_core: no health reporter in VF

Make sure the health reporter is set up before we use it in
our devlink health updates, especially since the VF doesn't
set up the health reporter.

Fixes: 25b450c

pds_core: no health reporter in VF

Make sure the health reporter is set up before we use it in
our devlink health updates, especially since the VF doesn't
set up the health reporter.

Fixes: 25b450c05a49 ("pds_core: add devlink health facilities")
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230824161754.34264-3-shannon.nelson@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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pds_core: use vmalloc_array and vcalloc

Use vmalloc_array and vcalloc to protect against
multiplication overflows.

The changes were done using the following Coccinelle
semantic patch:

// <smpl>
@i

pds_core: use vmalloc_array and vcalloc

Use vmalloc_array and vcalloc to protect against
multiplication overflows.

The changes were done using the following Coccinelle
semantic patch:

// <smpl>
@initialize:ocaml@
@@

let rename alloc =
match alloc with
"vmalloc" -> "vmalloc_array"
| "vzalloc" -> "vcalloc"
| _ -> failwith "unknown"

@@
size_t e1,e2;
constant C1, C2;
expression E1, E2, COUNT, x1, x2, x3;
typedef u8;
typedef __u8;
type t = {u8,__u8,char,unsigned char};
identifier alloc = {vmalloc,vzalloc};
fresh identifier realloc = script:ocaml(alloc) { rename alloc };
@@

(
alloc(x1*x2*x3)
|
alloc(C1 * C2)
|
alloc((sizeof(t)) * (COUNT), ...)
|
- alloc((e1) * (e2))
+ realloc(e1, e2)
|
- alloc((e1) * (COUNT))
+ realloc(COUNT, e1)
|
- alloc((E1) * (E2))
+ realloc(E1, E2)
)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Link: https://lore.kernel.org/r/20230627144339.144478-10-Julia.Lawall@inria.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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pds_core: publish events to the clients

When the Core device gets an event from the device, or notices
the device FW to be up or down, it needs to send those events
on to the clients that have an ev

pds_core: publish events to the clients

When the Core device gets an event from the device, or notices
the device FW to be up or down, it needs to send those events
on to the clients that have an event handler. Add the code to
pass along the events to the clients.

The entry points pdsc_register_notify() and pdsc_unregister_notify()
are EXPORTed for other drivers that want to listen for these events.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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pds_core: set up the VIF definitions and defaults

The Virtual Interfaces (VIFs) supported by the DSC's
configuration (vDPA, Eth, RDMA, etc) are reported in the
dev_ident struct and made visible in d

pds_core: set up the VIF definitions and defaults

The Virtual Interfaces (VIFs) supported by the DSC's
configuration (vDPA, Eth, RDMA, etc) are reported in the
dev_ident struct and made visible in debugfs. At this point
only vDPA is supported in this driver so we only setup
devices for that feature.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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pds_core: Add adminq processing and commands

Add the service routines for submitting and processing
the adminq messages and for handling notifyq events.

Signed-off-by: Shannon Nelson <shannon.nelso

pds_core: Add adminq processing and commands

Add the service routines for submitting and processing
the adminq messages and for handling notifyq events.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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pds_core: set up device and adminq

Set up the basic adminq and notifyq queue structures. These are
used mostly by the client drivers for feature configuration.
These are essentially the same adminq

pds_core: set up device and adminq

Set up the basic adminq and notifyq queue structures. These are
used mostly by the client drivers for feature configuration.
These are essentially the same adminq and notifyq as in the
ionic driver.

Part of this includes querying for device identity and FW
information, so we can make that available to devlink dev info.

$ devlink dev info pci/0000:b5:00.0
pci/0000:b5:00.0:
driver pds_core
serial_number FLM18420073
versions:
fixed:
asic.id 0x0
asic.rev 0x0
running:
fw 1.51.0-73
stored:
fw.goldfw 1.15.9-C-22
fw.mainfwa 1.60.0-73
fw.mainfwb 1.60.0-57

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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pds_core: add devlink health facilities

Add devlink health reporting on top of our fw watchdog.

Example:
# devlink health show pci/0000:2b:00.0 reporter fw
pci/0000:2b:00.0:
reporter fw

pds_core: add devlink health facilities

Add devlink health reporting on top of our fw watchdog.

Example:
# devlink health show pci/0000:2b:00.0 reporter fw
pci/0000:2b:00.0:
reporter fw
state healthy error 0 recover 0
# devlink health diagnose pci/0000:2b:00.0 reporter fw
Status: healthy State: 1 Generation: 0 Recoveries: 0

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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pds_core: health timer and workqueue

Add in the periodic health check and the related workqueue,
as well as the handlers for when a FW reset is seen.

The firmware is polled every 5 seconds to be su

pds_core: health timer and workqueue

Add in the periodic health check and the related workqueue,
as well as the handlers for when a FW reset is seen.

The firmware is polled every 5 seconds to be sure that it is
still alive and that the FW generation didn't change.

The alive check looks to see that the PCI bus is still readable
and the fw_status still has the RUNNING bit on. If not alive,
the driver stops activity and tears things down. When the FW
recovers and the alive check again succeeds, the driver sets
back up for activity.

The generation check looks at the fw_generation to see if it
has changed, which can happen if the FW crashed and recovered
or was updated in between health checks. If changed, the
driver counts that as though the alive test failed and forces
the fw_down/fw_up cycle.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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pds_core: add devcmd device interfaces

The devcmd interface is the basic connection to the device through the
PCI BAR for low level identification and command services. This does
the early device i

pds_core: add devcmd device interfaces

The devcmd interface is the basic connection to the device through the
PCI BAR for low level identification and command services. This does
the early device initialization and finds the identity data, and adds
devcmd routines to be used by later driver bits.

Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...