pci_msix_validate_entries() validates the entries array which is handed in
by the caller for a MSI-X interrupt allocation. Aside of consistency
failures it also detects a failure when the size of the MSI-X hardware table
in the device is smaller than the size of the entries array.
That's wrong for the case of range allocations where the caller provides
the minimum and the maximum number of vectors to allocate, when the
hardware size is greater or equal than the mininum, but smaller than the
maximum.
Remove the hardware size check completely from that function and just
ensure that the entires array up to the maximum size is consistent.
The limitation and range checking versus the hardware size happens
independently of that afterwards anyway because the entries array is
optional.
Fixes: 4644d22eb6 ("PCI/MSI: Validate MSI-X contiguous restriction early")
Reported-by: David Laight <David.Laight@aculab.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87v8i3sg62.ffs@tglx
The upcoming mechanism to allocate MSI-X vectors after enabling MSI-X needs
to share some of the MSI-X descriptor setup.
The regular descriptor setup on enable has the following code flow:
1) Allocate descriptor
2) Setup descriptor with PCI specific data
3) Insert descriptor
4) Allocate interrupts which in turn scans the inserted
descriptors
This cannot be easily changed because the PCI/MSI code needs to handle the
legacy architecture specific allocation model and the irq domain model
where quite some domains have the assumption that the above flow is how it
works.
Ideally the code flow should look like this:
1) Invoke allocation at the MSI core
2) MSI core allocates descriptor
3) MSI core calls back into the irq domain which fills in
the domain specific parts
This could be done for underlying parent MSI domains which support
post-enable allocation/free but that would create significantly different
code pathes for MSI/MSI-X enable.
Though for dynamic allocation which wants to share the allocation code with
the upcoming PCI/IMS support it's the right thing to do.
Split the MSI-X descriptor setup into the preallocation part which just sets
the index and fills in the horrible hack of virtual IRQs and the real PCI
specific MSI-X setup part which solely depends on the index in the
descriptor. This allows to provide a common dynamic allocation interface at
the MSI core level for both PCI/MSI-X and PCI/IMS.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221124232326.616292598@linutronix.de
Provide a template and the necessary callbacks to create PCI/MSI and
PCI/MSI-X domains.
The domains are created when MSI or MSI-X is enabled. The domain's lifetime
is either the device lifetime or in case that e.g. MSI-X was tried first
and failed, then the MSI-X domain is removed and a MSI domain is created as
both are mutually exclusive and reside in the default domain ID slot of the
per device domain pointer array.
Also expand pci_msi_domain_supports() to handle feature checks correctly
even in the case that the per device domain was not yet created by checking
the features supported by the MSI parent.
Add the necessary setup calls into the MSI and MSI-X enable code path.
These setup calls are backwards compatible. They return success when there
is no parent domain found, which means the existing global domains or the
legacy allocation path keep just working.
Co-developed-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221124232325.975388241@linutronix.de
With interrupt domains the sanity check for MSI-X vector validation can be
done _before_ any allocation happens. The sanity check only applies to the
allocation functions which have an 'entries' array argument. The entries
array is filled by the caller with the requested MSI-X indices. Some drivers
have gaps in the index space which is not supported on all architectures.
The PCI/MSI irq domain has a 'feature' bit to enforce this validation late
during the allocation phase.
Just do it right away before doing any other work along with the other
sanity checks on that array.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20221111122015.691357406@linutronix.de
When hierarchical MSI interrupt domains are enabled then there is no point
to do tons of work and detect the missing support for multi-MSI late in the
allocation path.
Just query the domain feature flags right away. The query function is going
to be used for other purposes later and has a mode argument which influences
the result:
ALLOW_LEGACY returns true when:
- there is no irq domain attached (legacy support)
- there is a irq domain attached which has the feature flag set
DENY_LEGACY returns only true when:
- there is a irq domain attached which has the feature flag set
This allows to use the function universally without ifdeffery in the
calling code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20221111122015.574339988@linutronix.de
There is no way to navigate msi.c without banging the head against the wall
every now and then because MSI and MSI-X specific functions are
intermingled and the code flow is completely non-obvious.
Reorder everthing so common helpers, MSI and MSI-X specific functions are
grouped together.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20221111122015.459089736@linutronix.de
msi.c is a maze of randomly sorted functions which makes the code
unreadable. As a first step split the driver visible API and the internal
implementation which also allows proper API documentation via one file.
Create drivers/pci/msi/api.c to group all exported device-driver PCI/MSI
APIs in one C file.
Begin by moving pci_disable_msi() there and add kernel-doc for the function
as appropriate.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20221111122014.696798036@linutronix.de
71020a3c0d ("PCI/MSI: Use msi_add_msi_desc()") inadvertently reversed
the sense of "msi_attrib.can_mask" in one use:
- if (entry->pci.msi_attrib.can_mask) {
- addr = pci_msix_desc_addr(entry);
- entry->pci.msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL);
+ if (!desc.pci.msi_attrib.can_mask) {
+ addr = pci_msix_desc_addr(&desc);
+ desc.pci.msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL);
Restore the original test.
[bhelgaas: commit log]
Fixes: 71020a3c0d ("PCI/MSI: Use msi_add_msi_desc()")
Link: https://lore.kernel.org/r/d818f9c9-a432-213e-4152-eaff3b7da52e@oderland.se
Signed-off-by: Josef Johansson <josef@oderland.se>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
The recent overhaul of pci_irq_get_affinity() introduced a regression when
pci_irq_get_affinity() is called for an MSI-X interrupt which was not
allocated with affinity descriptor information.
The original code just returned a NULL pointer in that case, but the rework
added a WARN_ON() under the assumption that the corresponding WARN_ON() in
the MSI case can be applied to MSI-X as well.
In fact the MSI warning in the original code does not make sense either
because it's legitimate to invoke pci_irq_get_affinity() for a MSI
interrupt which was not allocated with affinity descriptor information.
Remove it and just return NULL as the original code did.
Fixes: f482359001 ("PCI/MSI: Simplify pci_irq_get_affinity()")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/87ee4n38sm.ffs@tglx
The recent cleanup of pci_irq_get_affinity() broke the function for
PCI/MSI-X and indices > 0. Only the MSI descriptor for PCI/MSI has more
than one affinity mask which can be retrieved via the MSI index.
PCI/MSI-X has one descriptor per vector and each has a single affinity
mask.
Use index 0 when accessing the affinity mask in the MSI descriptor when
MSI-X is enabled.
Fixes: f482359001 ("PCI/MSI: Simplify pci_irq_get_affinity()")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/87v8zm9pmd.ffs@tglx
To prepare for dynamic extension of MSI-X vectors, protect the MSI
operations for MSI and MSI-X. This requires to move the invocation of
irq_create_affinity_masks() out of the descriptor lock section to avoid
reverse lock ordering vs. CPU hotplug lock as some callers of the PCI/MSI
allocation interfaces already hold it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20211206210747.982292705@linutronix.de
The MSI core will introduce runtime allocation of MSI related data. This
data will be devres managed and has to be set up before enabling
PCI/MSI[-X]. This would introduce an ordering issue vs. pcim_release().
The setup order is:
pcim_enable_device()
devres_alloc(pcim_release...);
...
pci_irq_alloc()
msi_setup_device_data()
devres_alloc(msi_device_data_release, ...)
and once the device is released these release functions are invoked in the
opposite order:
msi_device_data_release()
...
pcim_release()
pci_disable_msi[x]()
which is obviously wrong, because pci_disable_msi[x]() requires the MSI
data to be available to tear down the MSI[-X] interrupts.
Remove the MSI[-X] teardown from pcim_release() and add an explicit action
to be installed on the attempt of enabling PCI/MSI[-X].
This allows the MSI core data allocation to be ordered correctly in a
subsequent step.
Reported-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/87tuf9rdoj.ffs@tglx
There are quite some places which retrieve the first MSI descriptor to
evaluate whether the setup is for MSI or MSI-X. That's required because
pci_dev::msi[x]_enabled is only set when the setup completed successfully.
There is no real reason why msi[x]_enabled can't be set at the beginning of
the setup sequence and cleared in case of a failure.
Implement that so the MSI descriptor evaluations can be converted to simple
property queries.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20211210221813.250049810@linutronix.de
