linux-kernel - Re: [PATCH 1/1 v3] PCI: Device specific reset function

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CAErSpo4yiMrBcBPSV5MLKYsLQwhBA4L-fOHr4ocHDO9NwBpG7Q@mail.gmail.com>
Date:	Mon, 5 Mar 2012 11:03:38 -0700
From:	Bjorn Helgaas <bhelgaas@...gle.com>
To:	Tadeusz Struk <tadeusz.struk@...el.com>
Cc:	jbarnes@...tuousgeek.org, linux-kernel@...r.kernel.org,
	kvm@...r.kernel.org, linux-pci@...r.kernel.org
Subject: Re: [PATCH 1/1 v3] PCI: Device specific reset function

On Mon, Mar 5, 2012 at 3:00 AM, Tadeusz Struk <tadeusz.struk@...el.com> wrote:
>
> ---
>  drivers/pci/pci.h    |    1 +
>  drivers/pci/quirks.c |   33 +++++++++++++++++++++++++++------
>  include/linux/pci.h  |    1 +
>  3 files changed, 29 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 1009a5e..4d10479 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -315,6 +315,7 @@ struct pci_dev_reset_methods {
>        u16 vendor;
>        u16 device;
>        int (*reset)(struct pci_dev *dev, int probe);
> +       struct list_head list;
>  };
>
>  #ifdef CONFIG_PCI_QUIRKS
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 6476547..f423d2f 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -3070,26 +3070,47 @@ static int reset_intel_82599_sfp_virtfn(struct pci_dev *dev, int probe)
>  }
>
>  #define PCI_DEVICE_ID_INTEL_82599_SFP_VF   0x10ed
> -
> -static const struct pci_dev_reset_methods pci_dev_reset_methods[] = {
> +static struct pci_dev_reset_methods pci_dev_reset_methods[] = {
>        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82599_SFP_VF,
> -                reset_intel_82599_sfp_virtfn },
> +               reset_intel_82599_sfp_virtfn },
>        { PCI_VENDOR_ID_INTEL, PCI_ANY_ID,
>                reset_intel_generic_dev },
> -       { 0 }
>  };
>
> +static LIST_HEAD(reset_list);
> +
> +void pci_dev_specific_reset_add(struct pci_dev_reset_methods *reset_method)
> +{
> +       INIT_LIST_HEAD(&reset_method->list);
> +       list_add(&reset_method->list, &reset_list);
> +}
> +
> +static int __init pci_dev_specific_reset_init(void)
> +{
> +       int i;
> +
> +       for (i = 0; i < ARRAY_SIZE(pci_dev_reset_methods); i++) {
> +               pci_dev_specific_reset_add(&pci_dev_reset_methods[i]);
> +       }
> +       return 0;
> +}
> +
> +late_initcall(pci_dev_specific_reset_init);
> +
>  int pci_dev_specific_reset(struct pci_dev *dev, int probe)
>  {
>        const struct pci_dev_reset_methods *i;
> +       struct pci_driver *drv = dev->driver;
> +
> +       if (drv && drv->reset)
> +               return drv->reset(dev, probe);
>
> -       for (i = pci_dev_reset_methods; i->reset; i++) {
> +       list_for_each_entry(i, &reset_list, list) {
>                if ((i->vendor == dev->vendor ||
>                     i->vendor == (u16)PCI_ANY_ID) &&
>                    (i->device == dev->device ||
>                     i->device == (u16)PCI_ANY_ID))
>                        return i->reset(dev, probe);
>        }
> -
>        return -ENOTTY;
>  }
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index a16b1df..a3a0bc5 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -560,6 +560,7 @@ struct pci_driver {
>        int  (*resume_early) (struct pci_dev *dev);
>        int  (*resume) (struct pci_dev *dev);                   /* Device woken up */
>        void (*shutdown) (struct pci_dev *dev);
> +       int  (*reset) (struct pci_dev *dev, int probe); /* Device specific reset */
>        struct pci_error_handlers *err_handler;
>        struct device_driver    driver;
>        struct pci_dynids dynids;

This patch now consists of two pieces:
  1) Convert the reset method table to a list, and
  2) Add the "reset" function pointer in struct pci_driver and the "if
(drv && drv->reset)" block.

These should be split into two patches.

After you split them, I don't think you even need part 1, so you
should probably just drop it.

Common practice would be to also include your driver patch that
actually uses the pci_driver.reset pointer as an additional patch in
the same series.  That gives us more confidence that this solution
actually works and will be used.

Bjorn
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/