Re: [PATCH v2 3/4] PCI: Export pci_dev_lock()

[Bjorn Helgaas <helgaas@kernel.org>]

On Thu, Sep 16, 2021 at 11:33:35AM +0200, Niklas Schnelle wrote:
> Commit e3a9b1212b9d ("PCI: Export pci_dev_trylock() and pci_dev_unlock()")
> already exported pci_dev_trylock()/pci_dev_unlock() however in some
> circumstances such as during error recovery it makes sense to block
> waiting to get full access to the device so also export pci_dev_lock().
> 
> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>

Acked-by: Bjorn Helgaas <bhelgaas@google.com>

> ---
>  drivers/pci/pci.c   | 3 ++-
>  include/linux/pci.h | 1 +
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index ce2ab62b64cf..6fe810fdb796 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -5059,12 +5059,13 @@ static int pci_reset_bus_function(struct pci_dev *dev, bool probe)
>  	return pci_parent_bus_reset(dev, probe);
>  }
>  
> -static void pci_dev_lock(struct pci_dev *dev)
> +void pci_dev_lock(struct pci_dev *dev)
>  {
>  	pci_cfg_access_lock(dev);
>  	/* block PM suspend, driver probe, etc. */
>  	device_lock(&dev->dev);
>  }
> +EXPORT_SYMBOL_GPL(pci_dev_lock);
>  
>  /* Return 1 on successful lock, 0 on contention */
>  int pci_dev_trylock(struct pci_dev *dev)
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index cd8aa6fce204..c27c8fd1d30c 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1671,6 +1671,7 @@ void pci_cfg_access_lock(struct pci_dev *dev);
>  bool pci_cfg_access_trylock(struct pci_dev *dev);
>  void pci_cfg_access_unlock(struct pci_dev *dev);
>  
> +void pci_dev_lock(struct pci_dev *dev);
>  int pci_dev_trylock(struct pci_dev *dev);
>  void pci_dev_unlock(struct pci_dev *dev);
>  
> -- 
> 2.25.1
>