Commit 7d5ec3d36123 ("PCI/MSI: Mask all unused MSI-X entries") introduced a
readl() from ENTRY_VECTOR_CTRL before the writel() to ENTRY_DATA.

This is correct, however some hardware, like the Sun Neptune chips, the NIU
module, will cause an error and/or fatal trap if any MSIX table entry is
read before the corresponding ENTRY_DATA field is written to.

Add an optional early writel() in msix_prepare_msi_desc().

Fixes: 7d5ec3d36123 ("PCI/MSI: Mask all unused MSI-X entries")
Signed-off-by: Jonathan Currier <dullfire@yahoo.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20241117234843.19236-2-dullfire@yahoo.com

- Use pci_resource_n() to simplify BAR/window resource lookup (Ilpo
  Järvinen)

- Fix typo that repeatedly distributed resources to a bridge instead of
  iterating over subordinate bridges, which resulted in too little space to
  assign some BARs (Kai-Heng Feng)

- Relax bridge window tail sizing for optional resources, e.g., IOV BARs,
  to avoid failures when removing and re-adding devices (Ilpo Järvinen)

- Fix a double counting error for I/O resources, as we previously did for
  memory resources (Ilpo Järvinen)

- Use resource_set_{range,size}() helpers in more places (Ilpo Järvinen)

- Add pci_resource_is_iov() to identify IOV resources (Ilpo Järvinen)

- Add pci_resource_num() to look up the BAR number from the resource
  pointer (Ilpo Järvinen)

- Add restore_dev_resource() to simplify code that resources saved device
  resources (Ilpo Järvinen)

- Allow drivers to enable devices even if we haven't assigned optional IOV
  resources to them (Ilpo Järvinen)

- Improve debug output during resource reallocation (Ilpo Järvinen)

- Rework handling of optional resources (IOV BARs, ROMs) to reduce failures
  if we can't allocate them (Ilpo Järvinen)

- Move declarations of pci_rescan_bus_bridge_resize(),
  pci_reassign_bridge_resources(), and CardBus-related sizes from
  include/linux/pci.h to drivers/pci/pci.h since they're not used outside
  the PCI core (Ilpo Järvinen)

- Make pci_setup_bridge() static (Ilpo Järvinen)

- Fix a NULL dereference in the SR-IOV VF creation error path (Shay Drory)

- Fix s390 mmio_read/write syscalls, which didn't cause page faults in some
  cases, which broke vfio-pci lazy mapping on first access (Niklas
  Schnelle)

- Add pdev->non_mappable_bars to replace CONFIG_VFIO_PCI_MMAP, which was
  disabled only for s390 (Niklas Schnelle)

- Support mmap of PCI resources on s390 except for ISM devices (Niklas
  Schnelle)

* pci/resource:
  s390/pci: Support mmap() of PCI resources except for ISM devices
  s390/pci: Introduce pdev->non_mappable_bars and replace VFIO_PCI_MMAP
  s390/pci: Fix s390_mmio_read/write syscall page fault handling
  PCI: Fix NULL dereference in SR-IOV VF creation error path
  PCI: Move cardbus IO size declarations into pci/pci.h
  PCI: Make pci_setup_bridge() static
  PCI: Move resource reassignment func declarations into pci/pci.h
  PCI: Move pci_rescan_bus_bridge_resize() declaration to pci/pci.h
  PCI: Fix BAR resizing when VF BARs are assigned
  PCI: Do not claim to release resource falsely
  PCI: Increase Resizable BAR support from 512 GB to 128 TB
  PCI: Rework optional resource handling
  PCI: Perform reset_resource() and build fail list in sync
  PCI: Use res->parent to check if resource is assigned
  PCI: Add debug print when releasing resources before retry
  PCI: Indicate optional resource assignment failures
  PCI: Always have realloc_head in __assign_resources_sorted()
  PCI: Extend enable to check for any optional resource
  PCI: Add restore_dev_resource()
  PCI: Remove incorrect comment from pci_reassign_resource()
  PCI: Consolidate assignment loop next round preparation
  PCI: Rename retval to ret
  PCI: Use while loop and break instead of gotos
  PCI: Refactor pdev_sort_resources() & __dev_sort_resources()
  PCI: Converge return paths in __assign_resources_sorted()
  PCI: Add dev & res local variables to resource assignment funcs
  PCI: Add pci_resource_num() helper
  PCI: Check resource_size() separately
  PCI: Add pci_resource_is_iov() to identify IOV resources
  PCI: Use resource_set_{range,size}() helpers
  PCI: Use SZ_* instead of literals in setup-bus.c
  PCI: Fix old_size lower bound in calculate_iosize() too
  PCI: Allow relaxed bridge window tail sizing for optional resources
  PCI: Simplify size1 assignment logic
  PCI: Use min_align, not unrelated add_align, for size0
  PCI: Remove add_align overwrite unrelated to size0
  PCI: Use downstream bridges for distributing resources
  PCI: Cleanup dev->resource + resno to use pci_resource_n()

- Drop shpchp module init/exit logging (Ilpo Järvinen)

- Replace shpchp dbg() with ctrl_dbg() and remove unused dbg(), err(),
  info(), warn() wrappers (Ilpo Järvinen)

- Drop 'shpchp_debug' module parameter in favor of standard dynamic
  debugging (Ilpo Järvinen)

- Drop unused .get_power(), .set_power() function pointers (Guilherme
  Giacomo Simoes)

- Drop superfluous pci_hotplug_slot_list (Lukas Wunner)

- Drop superfluous try_module_get() calls (Lukas Wunner)

- Drop superfluous NULL pointer checks (Lukas Wunner)

- Pass struct hotplug_slot pointers directly to avoid backpointer
  dereferencing in has_*_file() (Lukas Wunner)

- Inline pci_hp_{create,remove}_module_link() to reduce exported symbols
  (Lukas Wunner)

- Disable hotplug interrupts in portdrv only when pciehp is not enabled to
  prevent issuing two hotplug commands too close together (Feng Tang)

- Skip pciehp 'device replaced' check if the device has been removed to
  address a common deadlock when resuming after a device was removed during
  system sleep (Lukas Wunner)

- Don't enable pciehp hotplug interupt when resuming in poll mode (Ilpo
  Järvinen)

* pci/hotplug:
  PCI: pciehp: Don't enable HPIE when resuming in poll mode
  PCI: pciehp: Avoid unnecessary device replacement check
  PCI/portdrv: Only disable pciehp interrupts early when needed
  PCI: hotplug: Inline pci_hp_{create,remove}_module_link()
  PCI: hotplug: Avoid backpointer dereferencing in has_*_file()
  PCI: hotplug: Drop superfluous NULL pointer checks in has_*_file()
  PCI: hotplug: Drop superfluous try_module_get() calls
  PCI: hotplug: Drop superfluous pci_hotplug_slot_list
  PCI: cpcihp: Remove unused .get_power() and .set_power()
  PCI: shpchp: Remove 'shpchp_debug' module parameter
  PCI: shpchp: Remove unused logging wrappers
  PCI: shpchp: Change dbg() -> ctrl_dbg()
  PCI: shpchp: Remove logging from module init/exit functions

- Enable Configuration RRS SV early instead of during child bus scanning
  (Bjorn Helgaas)

- Cache offset of Resizable BAR capability to avoid redundant searches for
  it (Bjorn Helgaas)

- Fix reference leaks in pci_register_host_bridge() and
  pci_alloc_child_bus() (Ma Ke)

- Drop put_device() in pci_register_host_bridge() left over from converting
  device_register() to device_add() (Dan Carpenter)

* pci/enumeration:
  PCI: Remove stray put_device() in pci_register_host_bridge()
  PCI: Fix reference leak in pci_alloc_child_bus()
  PCI: Fix reference leak in pci_register_host_bridge()
  PCI: Cache offset of Resizable BAR capability
  PCI: Enable Configuration RRS SV early

The ability to map PCI resources to user-space is controlled by global
defines. For vfio there is VFIO_PCI_MMAP which is only disabled on s390 and
controls mapping of PCI resources using vfio-pci with a fallback option via
the pread()/pwrite() interface.

For the PCI core there is ARCH_GENERIC_PCI_MMAP_RESOURCE which enables a
generic implementation for mapping PCI resources plus the newer sysfs
interface. Then there is HAVE_PCI_MMAP which can be used with custom
definitions of pci_mmap_resource_range() and the historical /proc/bus/pci
interface. Both mechanisms are all or nothing.

For s390 mapping PCI resources is possible and useful for testing and
certain applications such as QEMU's vfio-pci based user-space NVMe driver.
For certain devices, however access to PCI resources via mappings to
user-space is not possible and these must be excluded from the general PCI
resource mapping mechanisms.

Introduce pdev->non_mappable_bars to indicate that a PCI device's BARs can
not be accessed via mappings to user-space. In the future this enables
per-device restrictions of PCI resource mapping.

For now, set this flag for all PCI devices on s390 in line with the
existing, general disable of PCI resource mapping. As s390 is the only user
of the VFI_PCI_MMAP Kconfig options this can already be replaced with a
check of this new flag. Also add similar checks in the other code protected
by HAVE_PCI_MMAP respectively ARCH_GENERIC_PCI_MMAP in preparation for
enabling these for supported devices.

Link: https://lore.kernel.org/lkml/20250212132808.08dcf03c.alex.williamson@redhat.com/
Link: https://lore.kernel.org/r/20250226-vfio_pci_mmap-v7-2-c5c0f1d26efd@linux.ibm.com
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

For some reason, cardbus related io/mem size declarations are in
linux/pci.h, whereas non-cardbus sizes are already in pci/pci.h.
Move all them into one place in pci/pci.h.

Link: https://lore.kernel.org/r/20250311174701.3586-4-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

pci_setup_bridge() is only used within setup-bus.c. Therefore, make it a
static function.

Link: https://lore.kernel.org/r/20250311174701.3586-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Neither pci_reassign_bridge_resources() nor pci_reassign_resource() is used
outside of the PCI subsystem. They seem to be naturally static functions
but since resource fitting/assignment is split between setup-bus.c and
setup-res.c, they fall into different sides of the divide and need to be
declared.

Move the declarations of pci_reassign_bridge_resources() and
pci_reassign_resource() into pci/pci.h to keep them internal to PCI
subsystem.

Link: https://lore.kernel.org/r/20250311174701.3586-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

pci_rescan_bus_bridge_resize() is only used by code inside PCI subsystem.
The comment also falsely advertises it to be for hotplug drivers, yet the
only caller is from sysfs store function. Move the function declaration
into pci/pci.h.

Link: https://lore.kernel.org/r/20250311174701.3586-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Previously most resizable BAR interfaces (pci_rebar_get_possible_sizes(),
pci_rebar_set_size(), etc) as well as pci_restore_state() searched config
space for a Resizable BAR capability.  Most devices don't have such a
capability, so this is wasted effort, especially for pci_restore_state().

Search for a Resizable BAR capability once at enumeration-time and cache
the offset so we don't have to search every time we need it.  No functional
change intended.

Link: https://lore.kernel.org/r/20250215000301.175097-3-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>