Re: [PATCH v10 4/7] PCI/DPC: Unify and plumb error handling into DPC

From: Christoph Hellwig
Date: Thu Feb 22 2018 - 13:40:04 EST


On Thu, Feb 22, 2018 at 09:32:09PM +0530, Oza Pawandeep wrote:
> Current DPC driver does not do recovery, e.g. calling end-point's driver's
> callbacks, which sanitize the sw.
>
> DPC driver implements link_reset callback, and calls pci_do_recovery.
>
> Signed-off-by: Oza Pawandeep <poza@xxxxxxxxxxxxxx>
>
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index a5a79f0..124f42e 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -343,6 +343,8 @@ static inline resource_size_t pci_resource_alignment(struct pci_dev *dev,
> void pci_enable_acs(struct pci_dev *dev);
>
> /* PCI error reporting and recovery */
> +#define DPC_FATAL 4
> +
> void pci_do_recovery(struct pci_dev *dev, int severity);
>
> #ifdef CONFIG_PCIEASPM
> diff --git a/drivers/pci/pcie/pcie-dpc.c b/drivers/pci/pcie/pcie-dpc.c
> index 38e40c6..208b427 100644
> --- a/drivers/pci/pcie/pcie-dpc.c
> +++ b/drivers/pci/pcie/pcie-dpc.c
> @@ -13,6 +13,7 @@
> #include <linux/pcieport_if.h>
> #include "../pci.h"
> #include "aer/aerdrv.h"
> +#include "portdrv.h"
>
> struct dpc_dev {
> struct pcie_device *dev;
> @@ -45,6 +46,60 @@ struct dpc_dev {
> "Memory Request Completion Timeout", /* Bit Position 18 */
> };
>
> +static int find_dpc_dev_iter(struct device *device, void *data)
> +{
> + struct pcie_port_service_driver *service_driver;
> + struct device **dev;
> +
> + dev = (struct device **) data;
> +
> + if (device->bus == &pcie_port_bus_type && device->driver) {
> + service_driver = to_service_driver(device->driver);

Please move the initial assignment to the declaration line to
clean this up a bit:

struct device **dev = (struct device **)data;

Same thing happens a couple more times in this patch.

> +EXPORT_SYMBOL(pci_find_dpc_service);

EXPORT_SYMBOL_GPL for PCI layer internals again - and ditto for
probably about everything in this series.

> #if IS_ENABLED(CONFIG_PCIEAER)
> - /* Use the aer driver of the component firstly */
> - driver = pci_find_aer_service(udev);
> + if ((severity == AER_FATAL) ||
> + (severity == AER_NONFATAL) ||
> + (severity == AER_CORRECTABLE))
> + driver = pci_find_aer_service(udev);
> #endif

No need for the inner braces here.

> - if (severity == AER_FATAL)
> + if ((severity == AER_FATAL) ||
> + (severity == DPC_FATAL))
> state = pci_channel_io_frozen;
> else
> state = pci_channel_io_normal;

Same here and a few more times below.