Re: [PATCH 2/2] PCI: Save properties required to handle FLR for replay purposes.

2017-05-30 Thread Bjorn Helgaas 
On Tue, May 30, 2017 at 09:25:49AM -0700, Ashok Raj wrote:
> From: CQ Tang 
> 
> Requires: https://patchwork.kernel.org/patch/9593891
> 
> 
> After a FLR, pci-states need to be restored. This patch saves PASID features
> and PRI reqs cached.
> 
> To: Bjorn Helgaas 
> To: Joerg Roedel 
> To: linux-...@vger.kernel.org
> To: linux-ker...@vger.kernel.org
> Cc: Jean-Phillipe Brucker 
> Cc: David Woodhouse 
> Cc: iommu@lists.linux-foundation.org
> 
> Signed-off-by: CQ Tang 
> Signed-off-by: Ashok Raj 
> ---
>  drivers/pci/ats.c   | 65 
> +
>  drivers/pci/pci.c   |  3 +++
>  include/linux/pci-ats.h | 10 
>  include/linux/pci.h |  6 +
>  4 files changed, 69 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
> index 2126497..a769955 100644
> --- a/drivers/pci/ats.c
> +++ b/drivers/pci/ats.c
> @@ -160,17 +160,16 @@ int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
>   if (!pos)
>   return -EINVAL;
>  
> - pci_read_config_word(pdev, pos + PCI_PRI_CTRL, );
>   pci_read_config_word(pdev, pos + PCI_PRI_STATUS, );
> - if ((control & PCI_PRI_CTRL_ENABLE) ||
> - !(status & PCI_PRI_STATUS_STOPPED))
> + if (!(status & PCI_PRI_STATUS_STOPPED))
>   return -EBUSY;
>  
>   pci_read_config_dword(pdev, pos + PCI_PRI_MAX_REQ, _requests);
>   reqs = min(max_requests, reqs);
> + pdev->pri_reqs_alloc = reqs;
>   pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs);
>  
> - control |= PCI_PRI_CTRL_ENABLE;
> + control = PCI_PRI_CTRL_ENABLE;
>   pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
>  
>   pdev->pri_enabled = 1;
> @@ -206,6 +205,29 @@ void pci_disable_pri(struct pci_dev *pdev)
>  EXPORT_SYMBOL_GPL(pci_disable_pri);
>  
>  /**
> + * pci_restore_pri_state - Restore PRI
> + * @pdev: PCI device structure
> + *
> + */
> +void pci_restore_pri_state(struct pci_dev *pdev)
> +{
> +   u16 control = PCI_PRI_CTRL_ENABLE;
> +   u32 reqs = pdev->pri_reqs_alloc;
> +   int pos;
> +
> +   pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
> +   if (!pos)
> +   return;
> +
> +   if (!pdev->pri_enabled)
> +   return;

I propose swapping the order of these tests, so that if PRI is not
enabled, we don't have to search for the capability.  Similarly for
PASID below.

I made these changes and re-indented these functions on my branch.  No
action required unless you object to these changes.

> +
> +   pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs);
> +   pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
> +}
> +EXPORT_SYMBOL_GPL(pci_restore_pri_state);
> +
> +/**
>   * pci_reset_pri - Resets device's PRI state
>   * @pdev: PCI device structure
>   *
> @@ -224,12 +246,7 @@ int pci_reset_pri(struct pci_dev *pdev)
>   if (!pos)
>   return -EINVAL;
>  
> - pci_read_config_word(pdev, pos + PCI_PRI_CTRL, );
> - if (control & PCI_PRI_CTRL_ENABLE)
> - return -EBUSY;
> -
> - control |= PCI_PRI_CTRL_RESET;
> -
> + control = PCI_PRI_CTRL_RESET;
>   pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
>  
>   return 0;
> @@ -259,12 +276,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
>   if (!pos)
>   return -EINVAL;
>  
> - pci_read_config_word(pdev, pos + PCI_PASID_CTRL, );
>   pci_read_config_word(pdev, pos + PCI_PASID_CAP, );
> -
> - if (control & PCI_PASID_CTRL_ENABLE)
> - return -EINVAL;
> -
>   supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
>  
>   /* User wants to enable anything unsupported? */
> @@ -272,6 +284,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
>   return -EINVAL;
>  
>   control = PCI_PASID_CTRL_ENABLE | features;
> + pdev->pasid_features = features;
>  
>   pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control);
>  
> @@ -305,6 +318,28 @@ void pci_disable_pasid(struct pci_dev *pdev)
>  EXPORT_SYMBOL_GPL(pci_disable_pasid);
>  
>  /**
> + * pci_restore_pasid_state - Restore PASID capabilities.
> + * @pdev: PCI device structure
> + *
> + */
> +void pci_restore_pasid_state(struct pci_dev *pdev)
> +{
> +   u16 control;
> +   int pos;
> +
> +   pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
> +   if (!pos)
> +   return;
> +
> +   if (!pdev->pasid_enabled)
> +   return;
> +
> +   control = PCI_PASID_CTRL_ENABLE | pdev->pasid_features;
> +   pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control);
> +}
> +EXPORT_SYMBOL_GPL(pci_restore_pasid_state);
> +
> +/**
>   * pci_pasid_features - Check which PASID features are supported
>   * @pdev: PCI device structure
>   *
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 7904d02..c9a6510 100644
> ---

Re: [PATCH 2/2] PCI: Save properties required to handle FLR for replay purposes.

2017-05-30 Thread Raj, Ashok 
On Tue, May 30, 2017 at 02:50:33PM -0500, Bjorn Helgaas wrote:
> On Tue, May 30, 2017 at 09:25:49AM -0700, Ashok Raj wrote:
> > From: CQ Tang 
> > 
> > Requires: https://patchwork.kernel.org/patch/9593891
> 
> The above patch (9593891) is not in my tree or Linus' tree, so I can't
> do anything with this yet.

I resent the patch as part of this series.. maybe should have massaged the 
commit message.. my bad :-(. Its the first patch in this series.

Jean mentioned it might take him a while before the SVM patches stabilize.
Since this patch is pretty much stand alone, he asked if i could resend it
along with the one i need.

Sorry for any confusion.

Cheers,
Ashok
> 
> > After a FLR, pci-states need to be restored. This patch saves PASID features
> > and PRI reqs cached.
> > 
> > To: Bjorn Helgaas 
> > To: Joerg Roedel 
> > To: linux-...@vger.kernel.org
> > To: linux-ker...@vger.kernel.org
> > Cc: Jean-Phillipe Brucker 
> > Cc: David Woodhouse 
> > Cc: iommu@lists.linux-foundation.org
> > 
> > Signed-off-by: CQ Tang 
> > Signed-off-by: Ashok Raj 
> > ---
> >  drivers/pci/ats.c   | 65 
> > +
> >  drivers/pci/pci.c   |  3 +++
> >  include/linux/pci-ats.h | 10 
> >  include/linux/pci.h |  6 +
> >  4 files changed, 69 insertions(+), 15 deletions(-)
> > 
> > diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
> > index 2126497..a769955 100644
> > --- a/drivers/pci/ats.c
> > +++ b/drivers/pci/ats.c
> > @@ -160,17 +160,16 @@ int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
> > if (!pos)
> > return -EINVAL;
> >  
> > -   pci_read_config_word(pdev, pos + PCI_PRI_CTRL, );
> > pci_read_config_word(pdev, pos + PCI_PRI_STATUS, );
> > -   if ((control & PCI_PRI_CTRL_ENABLE) ||
> > -   !(status & PCI_PRI_STATUS_STOPPED))
> > +   if (!(status & PCI_PRI_STATUS_STOPPED))
> > return -EBUSY;
> >  
> > pci_read_config_dword(pdev, pos + PCI_PRI_MAX_REQ, _requests);
> > reqs = min(max_requests, reqs);
> > +   pdev->pri_reqs_alloc = reqs;
> > pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs);
> >  
> > -   control |= PCI_PRI_CTRL_ENABLE;
> > +   control = PCI_PRI_CTRL_ENABLE;
> > pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
> >  
> > pdev->pri_enabled = 1;
> > @@ -206,6 +205,29 @@ void pci_disable_pri(struct pci_dev *pdev)
> >  EXPORT_SYMBOL_GPL(pci_disable_pri);
> >  
> >  /**
> > + * pci_restore_pri_state - Restore PRI
> > + * @pdev: PCI device structure
> > + *
> > + */
> > +void pci_restore_pri_state(struct pci_dev *pdev)
> > +{
> > +   u16 control = PCI_PRI_CTRL_ENABLE;
> > +   u32 reqs = pdev->pri_reqs_alloc;
> > +   int pos;
> > +
> > +   pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
> > +   if (!pos)
> > +   return;
> > +
> > +   if (!pdev->pri_enabled)
> > +   return;
> > +
> > +   pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs);
> > +   pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
> > +}
> > +EXPORT_SYMBOL_GPL(pci_restore_pri_state);
> > +
> > +/**
> >   * pci_reset_pri - Resets device's PRI state
> >   * @pdev: PCI device structure
> >   *
> > @@ -224,12 +246,7 @@ int pci_reset_pri(struct pci_dev *pdev)
> > if (!pos)
> > return -EINVAL;
> >  
> > -   pci_read_config_word(pdev, pos + PCI_PRI_CTRL, );
> > -   if (control & PCI_PRI_CTRL_ENABLE)
> > -   return -EBUSY;
> > -
> > -   control |= PCI_PRI_CTRL_RESET;
> > -
> > +   control = PCI_PRI_CTRL_RESET;
> > pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
> >  
> > return 0;
> > @@ -259,12 +276,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int 
> > features)
> > if (!pos)
> > return -EINVAL;
> >  
> > -   pci_read_config_word(pdev, pos + PCI_PASID_CTRL, );
> > pci_read_config_word(pdev, pos + PCI_PASID_CAP, );
> > -
> > -   if (control & PCI_PASID_CTRL_ENABLE)
> > -   return -EINVAL;
> > -
> > supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
> >  
> > /* User wants to enable anything unsupported? */
> > @@ -272,6 +284,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
> > return -EINVAL;
> >  
> > control = PCI_PASID_CTRL_ENABLE | features;
> > +   pdev->pasid_features = features;
> >  
> > pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control);
> >  
> > @@ -305,6 +318,28 @@ void pci_disable_pasid(struct pci_dev *pdev)
> >  EXPORT_SYMBOL_GPL(pci_disable_pasid);
> >  
> >  /**
> > + * pci_restore_pasid_state - Restore PASID capabilities.
> > + * @pdev: PCI device structure
> > + *
> > + */
> > +void pci_restore_pasid_state(struct pci_dev *pdev)
> > +{
> > +   u16 control;
> > +   int pos;
> > +
> > +   pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
> > +   if (!pos)
> > +   return;
> > +
> > +   if

[PATCH 2/2] PCI: Save properties required to handle FLR for replay purposes.

2017-05-30 Thread Ashok Raj 
From: CQ Tang 

Requires: https://patchwork.kernel.org/patch/9593891


After a FLR, pci-states need to be restored. This patch saves PASID features
and PRI reqs cached.

To: Bjorn Helgaas 
To: Joerg Roedel 
To: linux-...@vger.kernel.org
To: linux-ker...@vger.kernel.org
Cc: Jean-Phillipe Brucker 
Cc: David Woodhouse 
Cc: iommu@lists.linux-foundation.org

Signed-off-by: CQ Tang 
Signed-off-by: Ashok Raj 
---
 drivers/pci/ats.c   | 65 +
 drivers/pci/pci.c   |  3 +++
 include/linux/pci-ats.h | 10 
 include/linux/pci.h |  6 +
 4 files changed, 69 insertions(+), 15 deletions(-)

diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index 2126497..a769955 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -160,17 +160,16 @@ int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
if (!pos)
return -EINVAL;
 
-   pci_read_config_word(pdev, pos + PCI_PRI_CTRL, );
pci_read_config_word(pdev, pos + PCI_PRI_STATUS, );
-   if ((control & PCI_PRI_CTRL_ENABLE) ||
-   !(status & PCI_PRI_STATUS_STOPPED))
+   if (!(status & PCI_PRI_STATUS_STOPPED))
return -EBUSY;
 
pci_read_config_dword(pdev, pos + PCI_PRI_MAX_REQ, _requests);
reqs = min(max_requests, reqs);
+   pdev->pri_reqs_alloc = reqs;
pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs);
 
-   control |= PCI_PRI_CTRL_ENABLE;
+   control = PCI_PRI_CTRL_ENABLE;
pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
 
pdev->pri_enabled = 1;
@@ -206,6 +205,29 @@ void pci_disable_pri(struct pci_dev *pdev)
 EXPORT_SYMBOL_GPL(pci_disable_pri);
 
 /**
+ * pci_restore_pri_state - Restore PRI
+ * @pdev: PCI device structure
+ *
+ */
+void pci_restore_pri_state(struct pci_dev *pdev)
+{
+   u16 control = PCI_PRI_CTRL_ENABLE;
+   u32 reqs = pdev->pri_reqs_alloc;
+   int pos;
+
+   pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
+   if (!pos)
+   return;
+
+   if (!pdev->pri_enabled)
+   return;
+
+   pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs);
+   pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
+}
+EXPORT_SYMBOL_GPL(pci_restore_pri_state);
+
+/**
  * pci_reset_pri - Resets device's PRI state
  * @pdev: PCI device structure
  *
@@ -224,12 +246,7 @@ int pci_reset_pri(struct pci_dev *pdev)
if (!pos)
return -EINVAL;
 
-   pci_read_config_word(pdev, pos + PCI_PRI_CTRL, );
-   if (control & PCI_PRI_CTRL_ENABLE)
-   return -EBUSY;
-
-   control |= PCI_PRI_CTRL_RESET;
-
+   control = PCI_PRI_CTRL_RESET;
pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
 
return 0;
@@ -259,12 +276,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
if (!pos)
return -EINVAL;
 
-   pci_read_config_word(pdev, pos + PCI_PASID_CTRL, );
pci_read_config_word(pdev, pos + PCI_PASID_CAP, );
-
-   if (control & PCI_PASID_CTRL_ENABLE)
-   return -EINVAL;
-
supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
 
/* User wants to enable anything unsupported? */
@@ -272,6 +284,7 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
return -EINVAL;
 
control = PCI_PASID_CTRL_ENABLE | features;
+   pdev->pasid_features = features;
 
pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control);
 
@@ -305,6 +318,28 @@ void pci_disable_pasid(struct pci_dev *pdev)
 EXPORT_SYMBOL_GPL(pci_disable_pasid);
 
 /**
+ * pci_restore_pasid_state - Restore PASID capabilities.
+ * @pdev: PCI device structure
+ *
+ */
+void pci_restore_pasid_state(struct pci_dev *pdev)
+{
+   u16 control;
+   int pos;
+
+   pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
+   if (!pos)
+   return;
+
+   if (!pdev->pasid_enabled)
+   return;
+
+   control = PCI_PASID_CTRL_ENABLE | pdev->pasid_features;
+   pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control);
+}
+EXPORT_SYMBOL_GPL(pci_restore_pasid_state);
+
+/**
  * pci_pasid_features - Check which PASID features are supported
  * @pdev: PCI device structure
  *
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 7904d02..c9a6510 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -28,6 +28,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 
@@ -1171,6 +1172,8 @@ void pci_restore_state(struct pci_dev *dev)
 
/* PCI Express register must be restored first */
pci_restore_pcie_state(dev);
+   pci_restore_pasid_state(dev);
+   pci_restore_pri_state(dev);
pci_restore_ats_state(dev);
pci_restore_vc_state(dev);
 
diff --git a/include/linux/pci-ats.h b/include/linux/pci-ats.h
index 57e0b82..782fb8e 100644
--- a/include/linux/pci-ats.h