[00/20] PCI: Convert dynamic sysfs objects into static

Message

Krzysztof Wilczy��ski April 16, 2021, 8:58 p.m. UTC

Hello,

Currently, a lot of PCI-related sysfs objects that are created when
either the PCI driver is initialised or when a new device is added are
dynamically created under the "/sys/bus/pci/devices/..." path.

All the attributes are added when late_initcall() function executes when
the PCI driver, and hence the PCI sub-system, is initialised, and also
when the function pci_bus_add_devices() executes when a device is added:

  late_initcall()
    pci_sysfs_init()
      pci_create_sysfs_dev_files()
        sysfs_create_bin_file()

  pci_bus_add_devices()
    pci_bus_add_device()
      pci_create_sysfs_dev_files()
        ...

When a device is stopped and removed the pci_remove_sysfs_dev_files()
function executes dynamically removing all the attributes that were
previously added:

  pci_stop_bus_device()
    pci_stop_dev()
      pci_remove_sysfs_dev_files()
        sysfs_remove_bin_file()

The current implementation is known to cause problems [1].

As most of the PCI-related attributes does not need to be created and
removed dynamically, and thus there is no need to also manage their
create and remove life cycle manually.

This series aims to convert the majority of the dynamic sysfs objects
into static ones so that the PCI driver core can manage them
automatically when the device is either added or removed.

The aim is also to first reduce the reliance on using late_initcall()
and eventually remove the need for it completely - this hopefully should
move everything closer towards addressing the issue that has been
identified in [1].

Aside from converting sysfs objects, this series also offers a series of
style clean-up patches offering updates, style changes, etc.

1. https://lore.kernel.org/linux-pci/20200716110423.xtfyb3n6tn5ixedh@pali/

Krzysztof

Krzysztof Wilczyński (20):
  PCI: Convert dynamic "config" sysfs object into static
  PCI: Convert dynamic "rom" sysfs object into static
  PCI: Convert dynamic "reset" sysfs object into static
  PCI/VPD: Convert dynamic "vpd" sysfs object into static
  PCI: Convert dynamic "index" and "label" sysfs objects into static
  sysfs: Introduce BIN_ATTR_ADMIN_RO and BIN_ATTR_ADMIN_RW
  PCI: Convert PCI sysfs objects to use BIN_ATTR_ADMIN_RW macro
  PCI: Move to kstrtobool() to handle user input
  PCI: Use sysfs_emit() and sysfs_emit_at() in "show" functions
  PCI: Update style to be more consistent
  PCI: Rearrange attributes from the pci_dev_group
  PCI: Rearrange attributes from the pci_dev_config_attr_group
  PCI: Rearrange attributes from the pci_dev_rom_attr_group
  PCI: Rearrange attributes from the pci_dev_reset_attr_group
  PCI: Rearrange attributes from the pci_dev_attr_group
  PCI: Rearrange attributes from the pci_dev_hp_attr_group
  PCI: Rearrange attributes from the pci_bridge_attr_group
  PCI: Rearrange attributes from the pcie_dev_attr_group
  PCI: Rearrange attributes from the pci_bus_group
  PCI: Rearrange attributes from the pcibus_group

 drivers/pci/pci-label.c |  241 ++----
 drivers/pci/pci-sysfs.c | 1655 ++++++++++++++++++++-------------------
 drivers/pci/pci.h       |   16 +-
 drivers/pci/remove.c    |    2 +
 drivers/pci/vpd.c       |   58 +-
 include/linux/pci.h     |    1 -
 include/linux/sysfs.h   |   23 +
 7 files changed, 976 insertions(+), 1020 deletions(-)