Commit Graph

66 Commits

Author SHA1 Message Date
Vidya Sagar
db744ddd59 PCI/MSI: Prevent MSI hardware interrupt number truncation
While calculating the hardware interrupt number for a MSI interrupt, the
higher bits (i.e. from bit-5 onwards a.k.a domain_nr >= 32) of the PCI
domain number gets truncated because of the shifted value casting to return
type of pci_domain_nr() which is 'int'. This for example is resulting in
same hardware interrupt number for devices 0019:00:00.0 and 0039:00:00.0.

To address this cast the PCI domain number to 'irq_hw_number_t' before left
shifting it to calculate the hardware interrupt number.

Please note that this fixes the issue only on 64-bit systems and doesn't
change the behavior for 32-bit systems i.e. the 32-bit systems continue to
have the issue. Since the issue surfaces only if there are too many PCIe
controllers in the system which usually is the case in modern server
systems and they don't tend to run 32-bit kernels.

Fixes: 3878eaefb8 ("PCI/MSI: Enhance core to support hierarchy irqdomain")
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240115135649.708536-1-vidyas@nvidia.com
2024-02-19 16:11:01 +01:00
Ilpo Järvinen
682f5311e3 PCI/MSI: Use FIELD_GET/PREP()
Instead of custom masking and shifting, use FIELD_GET/PREP() with
register fields.

Link: https://lore.kernel.org/r/20231018113254.17616-8-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2023-10-24 10:54:04 -05:00
Bjorn Helgaas
86b4ad7d67 PCI: Fix typos in docs and comments
Fix typos in docs and comments.

Link: https://lore.kernel.org/r/20230824193712.542167-11-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2023-08-25 08:15:38 -05:00
Thomas Gleixner
e3c026be4d PCI/MSI: Remove over-zealous hardware size check in pci_msix_validate_entries()
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
2023-04-16 14:11:51 +02:00
Reinette Chatre
e6cc6f1755 PCI/MSI: Clarify usage of pci_msix_free_irq()
pci_msix_free_irq() is used to free an interrupt on a PCI/MSI-X interrupt
domain.

The API description specifies that the interrupt to be freed was allocated
via pci_msix_alloc_irq_at().  This description limits the usage of
pci_msix_free_irq() since pci_msix_free_irq() can also be used to free
MSI-X interrupts allocated with, for example, pci_alloc_irq_vectors().

Remove the text stating that the interrupt to be freed had to be allocated
with pci_msix_alloc_irq_at(). The needed struct msi_map need not be from
pci_msix_alloc_irq_at() but can be created from scratch using
pci_irq_vector() to obtain the Linux IRQ number. Highlight that
pci_msix_free_irq() cannot be used to disable MSI-X to guide users that,
for example, pci_free_irq_vectors() remains to be needed.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/lkml/87r0xsd8j4.ffs@tglx
Link: https://lore.kernel.org/r/4c3e7a50d6e70f408812cd7ab199c6b4b326f9de.1676408572.git.reinette.chatre@intel.com
2023-02-21 08:25:14 +01:00
Thomas Gleixner
c9e5bea273 PCI/MSI: Provide pci_ims_alloc/free_irq()
Single vector allocation which allocates the next free index in the IMS
space. The free function releases.

All allocated vectors are released also via pci_free_vectors() which is
also releasing MSI/MSI-X vectors.

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/20221124232326.961711347@linutronix.de
2022-12-05 22:22:35 +01:00
Thomas Gleixner
0194425af0 PCI/MSI: Provide IMS (Interrupt Message Store) support
IMS (Interrupt Message Store) is a new specification which allows
implementation specific storage of MSI messages contrary to the
strict standard specified MSI and MSI-X message stores.

This requires new device specific interrupt domains to handle the
implementation defined storage which can be an array in device memory or
host/guest memory which is shared with hardware queues.

Add a function to create IMS domains for PCI devices. IMS domains are using
the new per device domain mechanism and are configured by the device driver
via a template. IMS domains are created as secondary device domains so they
work side on side with MSI[-X] on the same device.

The IMS domains have a few constraints:

  - The index space is managed by the core code.

    Device memory based IMS provides a storage array with a fixed size
    which obviously requires an index. But there is no association between
    index and functionality so the core can randomly allocate an index in
    the array.

    System memory based IMS does not have the concept of an index as the
    storage is somewhere in memory. In that case the index is purely
    software based to keep track of the allocations.

  - There is no requirement for consecutive index ranges

    This is currently a limitation of the MSI core and can be implemented
    if there is a justified use case by changing the internal storage from
    xarray to maple_tree. For now it's single vector allocation.

  - The interrupt chip must provide the following callbacks:

  	- irq_mask()
	- irq_unmask()
	- irq_write_msi_msg()

   - The interrupt chip must provide the following optional callbacks
     when the irq_mask(), irq_unmask() and irq_write_msi_msg() callbacks
     cannot operate directly on hardware, e.g. in the case that the
     interrupt message store is in queue memory:

     	- irq_bus_lock()
	- irq_bus_unlock()

     These callbacks are invoked from preemptible task context and are
     allowed to sleep. In this case the mandatory callbacks above just
     store the information. The irq_bus_unlock() callback is supposed to
     make the change effective before returning.

   - Interrupt affinity setting is handled by the underlying parent
     interrupt domain and communicated to the IMS domain via
     irq_write_msi_msg(). IMS domains cannot have a irq_set_affinity()
     callback. That's a reasonable restriction similar to the PCI/MSI
     device domain implementations.

The domain is automatically destroyed when the PCI device is removed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221124232326.904316841@linutronix.de
2022-12-05 22:22:34 +01:00
Thomas Gleixner
34026364df PCI/MSI: Provide post-enable dynamic allocation interfaces for MSI-X
MSI-X vectors can be allocated after the initial MSI-X enablement, but this
needs explicit support of the underlying interrupt domains.

Provide a function to query the ability and functions to allocate/free
individual vectors post-enable.

The allocation can either request a specific index in the MSI-X table or
with the index argument MSI_ANY_INDEX it allocates the next free vector.

The return value is a struct msi_map which on success contains both index
and the Linux interrupt number. In case of failure index is negative and
the Linux interrupt number is 0.

The allocation function is for a single MSI-X index at a time as that's
sufficient for the most urgent use case VFIO to get rid of the 'disable
MSI-X, reallocate, enable-MSI-X' cycle which is prone to lost interrupts
and redirections to the legacy and obviously unhandled INTx.

As single index allocation is also sufficient for the use cases Jason
Gunthorpe pointed out: Allocation of a MSI-X or IMS vector for a network
queue. See Link below.

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/all/20211126232735.547996838@linutronix.de
Link: https://lore.kernel.org/r/20221124232326.731233614@linutronix.de
2022-12-05 22:22:34 +01:00
Thomas Gleixner
73bd063ca0 PCI/MSI: Provide prepare_desc() MSI domain op
The setup of MSI descriptors for PCI/MSI-X interrupts depends partially on
the MSI index for which the descriptor is initialized.

Dynamic MSI-X vector allocation post MSI-X enablement allows to allocate
vectors at a given index or at any free index in the available table
range. The latter requires that the descriptor is initialized after the
MSI core has chosen an index.

Implement the prepare_desc() op in the PCI/MSI-X specific msi_domain_ops
which is invoked before the core interrupt descriptor and the associated
Linux interrupt number is allocated.

That callback is also provided for the upcoming PCI/IMS implementations so
the implementation specific interrupt domain can do their domain specific
initialization of the MSI descriptors.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
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/20221124232326.673658806@linutronix.de
2022-12-05 22:22:34 +01:00
Thomas Gleixner
612ad43330 PCI/MSI: Split MSI-X descriptor setup
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
2022-12-05 22:22:34 +01:00
Thomas Gleixner
45c0402457 PCI/MSI: Remove unused pci_dev_has_special_msi_domain()
The check for special MSI domains like VMD which prevents the interrupt
remapping code to overwrite device::msi::domain is not longer required and
has been replaced by an x86 specific version which is aware of MSI parent
domains.

Remove it.

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/20221124232326.093093200@linutronix.de
2022-12-05 22:22:33 +01:00
Thomas Gleixner
15c72f824b PCI/MSI: Add support for per device MSI[X] domains
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
2022-12-05 22:22:32 +01:00
Thomas Gleixner
877d6c4e93 PCI/MSI: Split __pci_write_msi_msg()
The upcoming per device MSI domains will create different domains for MSI
and MSI-X. Split the write message function into MSI and MSI-X helpers so
they can be used by those new domain functions seperately.

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/20221124232325.857982142@linutronix.de
2022-12-05 22:22:32 +01:00
Thomas Gleixner
d3a11dee9f PCI/MSI: Use msi_domain_alloc/free_irqs_all_locked()
Switch to the new domain id aware interfaces to phase out the previous
ones. No functional change.

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/20221124230314.455168748@linutronix.de
2022-12-05 19:21:00 +01:00
Thomas Gleixner
1c89396300 genirq/msi: Rename msi_add_msi_desc() to msi_insert_msi_desc()
This reflects the functionality better. No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221124230314.103554618@linutronix.de
2022-12-05 19:20:59 +01:00
Bagas Sanjaya
6842694c50 PCI/MSI: Use bullet lists in kernel-doc comments of api.c
Use bullet-list RST syntax for kernel-doc parameters' flags and interrupt
mode descriptions. Otherwise Sphinx produces "Unexpected identation" errors
and warnings.

Fixes: 5c0997dc33 ("PCI/MSI: Move pci_alloc_irq_vectors() to api.c")
Fixes: 017239c8db ("PCI/MSI: Move pci_irq_vector() to api.c")
Fixes: be37b8428b ("PCI/MSI: Move pci_irq_get_affinity() to api.c")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Suggested-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ahmed S. Darwish <darwi@linutronix.de>
Link: https://lore.kernel.org/r/20221203100511.222136-1-bagasdotme@gmail.com
2022-12-05 18:57:46 +01:00
Thomas Gleixner
9c03b2589d PCI/MSI: Remove redundant msi_check() callback
All these sanity checks are now done _before_ any allocation work
happens. No point in doing it twice.

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/20221111122015.749446904@linutronix.de
2022-11-17 15:15:22 +01:00
Thomas Gleixner
4644d22eb6 PCI/MSI: Validate MSI-X contiguous restriction early
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
2022-11-17 15:15:22 +01:00
Thomas Gleixner
99f3d27976 PCI/MSI: Reject MSI-X early
Similar to PCI multi-MSI reject MSI-X enablement when a irq domain is
attached to the device which does not support MSI-X.

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/20221111122015.631728309@linutronix.de
2022-11-17 15:15:22 +01:00
Thomas Gleixner
d2a463b297 PCI/MSI: Reject multi-MSI early
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
2022-11-17 15:15:22 +01:00
Thomas Gleixner
bab65e48cb PCI/MSI: Sanitize MSI-X checks
There is no point in doing the same sanity checks over and over in a loop
during MSI-X enablement. Put them in front of the loop and return early
when they fail.

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/20221111122015.516946468@linutronix.de
2022-11-17 15:15:22 +01:00
Ahmed S. Darwish
12910ffd18 PCI/MSI: Reorder functions in msi.c
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
2022-11-17 15:15:21 +01:00
Ahmed S. Darwish
57127da98b PCI/MSI: Move pci_msi_restore_state() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.
    
Move pci_msi_enabled() and add kernel-doc for the function.

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/20221111122015.331584998@linutronix.de
2022-11-17 15:15:21 +01:00
Ahmed S. Darwish
897a0b6aa8 PCI/MSI: Move pci_msi_enabled() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_msi_enabled() and make its kernel-doc comprehensive.

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/20221111122015.271447896@linutronix.de
2022-11-17 15:15:21 +01:00
Ahmed S. Darwish
be37b8428b PCI/MSI: Move pci_irq_get_affinity() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_irq_get_affinity() and let its kernel-doc match rest of the
file.

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/20221111122015.214792769@linutronix.de
2022-11-17 15:15:21 +01:00
Ahmed S. Darwish
18e1926b8c PCI/MSI: Move pci_disable_msix() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_disable_msix() and make its kernel-doc comprehensive.

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/20221111122015.156785224@linutronix.de
2022-11-17 15:15:21 +01:00
Ahmed S. Darwish
7b50f62776 PCI/MSI: Move pci_msix_vec_count() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_msix_vec_count() and make its kernel-doc comprehensive.

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/20221111122015.099461602@linutronix.de
2022-11-17 15:15:21 +01:00
Ahmed S. Darwish
059f778d66 PCI/MSI: Move pci_free_irq_vectors() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_free_irq_vectors() and make its kernel-doc comprehensive.

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/20221111122015.042870570@linutronix.de
2022-11-17 15:15:21 +01:00
Ahmed S. Darwish
017239c8db PCI/MSI: Move pci_irq_vector() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_irq_vector() and let its kernel-doc match the rest of the file.

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/20221111122014.984490384@linutronix.de
2022-11-17 15:15:21 +01:00
Ahmed S. Darwish
beddb5efb4 PCI/MSI: Move pci_alloc_irq_vectors_affinity() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_alloc_irq_vectors_affinity() and let its kernel-doc reference
pci_alloc_irq_vectors() documentation added in parent commit.

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/20221111122014.927531290@linutronix.de
2022-11-17 15:15:20 +01:00
Ahmed S. Darwish
5c0997dc33 PCI/MSI: Move pci_alloc_irq_vectors() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Make pci_alloc_irq_vectors() a real function instead of wrapper and add
proper kernel doc to it.

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/20221111122014.870888193@linutronix.de
2022-11-17 15:15:20 +01:00
Ahmed S. Darwish
be7496c1ef PCI/MSI: Move pci_enable_msix_range() to api.c
To disentangle the maze in msi.c, all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_enable_msix_range() and make its kernel-doc comprehensive.

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/20221111122014.813792885@linutronix.de
2022-11-17 15:15:20 +01:00
Ahmed S. Darwish
bbda340798 PCI/MSI: Move pci_enable_msi() API to api.c
To disentangle the maze in msi.c all exported device-driver MSI APIs are
now to be grouped in one file, api.c.

Move pci_enable_msi() and make its kernel-doc comprehensive.

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/20221111122014.755178149@linutronix.de
2022-11-17 15:15:20 +01:00
Ahmed S. Darwish
b12d0bec38 PCI/MSI: Move pci_disable_msi() to api.c
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
2022-11-17 15:15:20 +01:00
Ahmed S. Darwish
c93fd5266c PCI/MSI: Move mask and unmask helpers to msi.h
The upcoming support for per device MSI interrupt domains needs to share
some of the inline helpers with the MSI implementation.

Move them to the header file.

Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
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/20221111122014.640052354@linutronix.de
2022-11-17 15:15:20 +01:00
Ahmed S. Darwish
db537dd3bf PCI/MSI: Get rid of externs in msi.h
Follow the style of <linux/pci.h>

Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
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/20221111122014.582175082@linutronix.de
2022-11-17 15:15:20 +01:00
Thomas Gleixner
a474d3fbe2 PCI/MSI: Get rid of PCI_MSI_IRQ_DOMAIN
What a zoo:

     PCI_MSI
	select GENERIC_MSI_IRQ

     PCI_MSI_IRQ_DOMAIN
     	def_bool y
	depends on PCI_MSI
	select GENERIC_MSI_IRQ_DOMAIN

Ergo PCI_MSI enables PCI_MSI_IRQ_DOMAIN which in turn selects
GENERIC_MSI_IRQ_DOMAIN. So all the dependencies on PCI_MSI_IRQ_DOMAIN are
just an indirection to PCI_MSI.

Match the reality and just admit that PCI_MSI requires
GENERIC_MSI_IRQ_DOMAIN.

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/20221111122014.467556921@linutronix.de
2022-11-17 15:15:19 +01:00
Ahmed S. Darwish
b2bdda205c PCI/MSI: Let the MSI core free descriptors
Let the core do the freeing of descriptors and just keep it around for the
legacy case.

Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
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/20221111122014.409654736@linutronix.de
2022-11-17 15:15:19 +01:00
Ahmed S. Darwish
38c0c10ae6 PCI/MSI: Use msi_domain_info:: Bus_token
Set the bus token in the msi_domain_info structure and let the core code
handle the update.

Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
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/20221111122014.352437595@linutronix.de
2022-11-17 15:15:19 +01:00
Thomas Gleixner
fe97f59a78 PCI/MSI: Check for MSI enabled in __pci_msix_enable()
PCI/MSI and PCI/MSI-X are mutually exclusive, but the MSI-X enable code
lacks a check for already enabled MSI.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20221111122013.653556720@linutronix.de
2022-11-17 15:15:18 +01:00
Josef Johansson
2b96f92ca4 PCI/MSI: Correct 'can_mask' test in msi_add_msi_desc()
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>
2022-08-26 10:47:54 -05:00
Thomas Gleixner
dd7f5a11ac PCI/MSI: Remove bogus warning in pci_irq_get_affinity()
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
2022-02-04 09:54:20 +01:00
Thomas Gleixner
a0af3d1104 PCI/MSI: Prevent UAF in error path
When the core MSI allocation fails, then the PCI/MSI code uses an already
freed MSI descriptor to unmask the MSI mask register in order to bring it back
into reset state.

Remove MSI_FLAG_FREE_MSI_DESCS from the PCI/MSI irqdomain flags and let the
PCI/MSI code free the MSI descriptors after usage.

Fixes: 0f62d941ac ("genirq/msi: Provide msi_domain_alloc/free_irqs_descs_locked()")
Reported-by: Tong Zhang <ztong0001@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Tong Zhang <ztong0001@gmail.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/87r1938vbn.ffs@tglx
2022-01-21 02:14:46 +01:00
Thomas Gleixner
d558285413 PCI/MSI: Unbreak pci_irq_get_affinity()
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
2021-12-18 20:33:21 +01:00
Thomas Gleixner
ae24e28fef PCI/MSI: Use msi_on_each_desc()
Use the new iterator functions which pave the way for dynamically extending
MSI-X vectors.

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/20211206210748.142603657@linutronix.de
2021-12-16 22:22:18 +01:00
Thomas Gleixner
9fb9eb4b59 PCI/MSI: Let core code free MSI descriptors
Set the domain info flag which tells the core code to free the MSI
descriptors from msi_domain_free_irqs() and add an explicit call to the
core function into the legacy code.

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/20211206210748.089085131@linutronix.de
2021-12-16 22:22:17 +01:00
Thomas Gleixner
71020a3c0d PCI/MSI: Use msi_add_msi_desc()
Simplify the allocation of MSI descriptors by using msi_add_msi_desc()
which moves the storage handling to core code and prepares for dynamic
extension of the MSI-X vector space.

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/20211206210748.035348646@linutronix.de
2021-12-16 22:22:17 +01:00
Thomas Gleixner
5512c5eaf5 PCI/MSI: Protect MSI operations
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
2021-12-16 22:22:17 +01:00
Thomas Gleixner
f482359001 PCI/MSI: Simplify pci_irq_get_affinity()
Replace open coded MSI descriptor chasing and use the proper accessor
functions instead.

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>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20211210221814.900929381@linutronix.de
2021-12-16 22:16:41 +01:00
Thomas Gleixner
82ff8e6b78 PCI/MSI: Use msi_get_virq() in pci_get_vector()
Use msi_get_vector() and handle the return value to be compatible.

No functional change intended.

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>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20211210221814.841243231@linutronix.de
2021-12-16 22:16:41 +01:00