Re: [patch V2 08/36] PCI/MSI: Let the irq code handle sysfs groups

[Bjorn Helgaas <helgaas@xxxxxxxxxx>]

On Mon, Dec 06, 2021 at 11:39:09PM +0100, Thomas Gleixner wrote:
> Set the domain info flag which makes the core code handle sysfs groups and
> put an explicit invocation into the legacy code.
> 
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>

Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>

> ---
>  drivers/pci/msi/irqdomain.c |    2 +-
>  drivers/pci/msi/legacy.c    |    6 +++++-
>  drivers/pci/msi/msi.c       |   23 -----------------------
>  include/linux/pci.h         |    1 -
>  4 files changed, 6 insertions(+), 26 deletions(-)
> 
> --- a/drivers/pci/msi/irqdomain.c
> +++ b/drivers/pci/msi/irqdomain.c
> @@ -159,7 +159,7 @@ struct irq_domain *pci_msi_create_irq_do
>       if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
>               pci_msi_domain_update_chip_ops(info);
>  
> -     info->flags |= MSI_FLAG_ACTIVATE_EARLY;
> +     info->flags |= MSI_FLAG_ACTIVATE_EARLY | MSI_FLAG_DEV_SYSFS;
>       if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE))
>               info->flags |= MSI_FLAG_MUST_REACTIVATE;
>  
> --- a/drivers/pci/msi/legacy.c
> +++ b/drivers/pci/msi/legacy.c
> @@ -70,10 +70,14 @@ int pci_msi_legacy_setup_msi_irqs(struct
>  {
>       int ret = arch_setup_msi_irqs(dev, nvec, type);
>  
> -     return pci_msi_setup_check_result(dev, type, ret);
> +     ret = pci_msi_setup_check_result(dev, type, ret);
> +     if (!ret)
> +             ret = msi_device_populate_sysfs(&dev->dev);
> +     return ret;
>  }
>  
>  void pci_msi_legacy_teardown_msi_irqs(struct pci_dev *dev)
>  {
> +     msi_device_destroy_sysfs(&dev->dev);
>       arch_teardown_msi_irqs(dev);
>  }
> --- a/drivers/pci/msi/msi.c
> +++ b/drivers/pci/msi/msi.c
> @@ -233,11 +233,6 @@ static void free_msi_irqs(struct pci_dev
>                       for (i = 0; i < entry->nvec_used; i++)
>                               BUG_ON(irq_has_action(entry->irq + i));
>  
> -     if (dev->msi_irq_groups) {
> -             msi_destroy_sysfs(&dev->dev, dev->msi_irq_groups);
> -             dev->msi_irq_groups = NULL;
> -     }
> -
>       pci_msi_teardown_msi_irqs(dev);
>  
>       list_for_each_entry_safe(entry, tmp, msi_list, list) {
> @@ -417,7 +412,6 @@ static int msi_verify_entries(struct pci
>  static int msi_capability_init(struct pci_dev *dev, int nvec,
>                              struct irq_affinity *affd)
>  {
> -     const struct attribute_group **groups;
>       struct msi_desc *entry;
>       int ret;
>  
> @@ -441,14 +435,6 @@ static int msi_capability_init(struct pc
>       if (ret)
>               goto err;
>  
> -     groups = msi_populate_sysfs(&dev->dev);
> -     if (IS_ERR(groups)) {
> -             ret = PTR_ERR(groups);
> -             goto err;
> -     }
> -
> -     dev->msi_irq_groups = groups;
> -
>       /* Set MSI enabled bits */
>       pci_intx_for_msi(dev, 0);
>       pci_msi_set_enable(dev, 1);
> @@ -576,7 +562,6 @@ static void msix_mask_all(void __iomem *
>  static int msix_capability_init(struct pci_dev *dev, struct msix_entry 
> *entries,
>                               int nvec, struct irq_affinity *affd)
>  {
> -     const struct attribute_group **groups;
>       void __iomem *base;
>       int ret, tsize;
>       u16 control;
> @@ -618,14 +603,6 @@ static int msix_capability_init(struct p
>  
>       msix_update_entries(dev, entries);
>  
> -     groups = msi_populate_sysfs(&dev->dev);
> -     if (IS_ERR(groups)) {
> -             ret = PTR_ERR(groups);
> -             goto out_free;
> -     }
> -
> -     dev->msi_irq_groups = groups;
> -
>       /* Set MSI-X enabled bits and unmask the function */
>       pci_intx_for_msi(dev, 0);
>       dev->msix_enabled = 1;
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -475,7 +475,6 @@ struct pci_dev {
>  #ifdef CONFIG_PCI_MSI
>       void __iomem    *msix_base;
>       raw_spinlock_t  msi_lock;
> -     const struct attribute_group **msi_irq_groups;
>  #endif
>       struct pci_vpd  vpd;
>  #ifdef CONFIG_PCIE_DPC
>