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[PATCH v4 3/7] PCI: Add a helper to convert between standard and IOV resources

Michał Winiarski posted 7 patches 1 year, 3 months ago
There is a newer version of this series
[PATCH v4 3/7] PCI: Add a helper to convert between standard and IOV resources
Posted by Michał Winiarski 1 year, 3 months ago 
There are multiple places where conversions between IOV resources and
standard resources are done.

Extract the logic to pci_resource_to_iov() and pci_resource_from_iov()
helpers.

Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
---
 drivers/pci/iov.c       | 20 ++++++++++----------
 drivers/pci/pci.h       | 18 ++++++++++++++++++
 drivers/pci/setup-bus.c |  2 +-
 3 files changed, 29 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index 6bdc9950b9787..eedc1df56c49e 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -151,7 +151,7 @@ resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
 	if (!dev->is_physfn)
 		return 0;
 
-	return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
+	return dev->sriov->barsz[pci_resource_from_iov(resno)];
 }
 
 static void pci_read_vf_config_common(struct pci_dev *virtfn)
@@ -322,12 +322,12 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id)
 	virtfn->multifunction = 0;
 
 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
-		res = &dev->resource[i + PCI_IOV_RESOURCES];
+		res = &dev->resource[pci_resource_to_iov(i)];
 		if (!res->parent)
 			continue;
 		virtfn->resource[i].name = pci_name(virtfn);
 		virtfn->resource[i].flags = res->flags;
-		size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
+		size = pci_iov_resource_size(dev, pci_resource_to_iov(i));
 		virtfn->resource[i].start = res->start + size * id;
 		virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
 		rc = request_resource(res, &virtfn->resource[i]);
@@ -624,8 +624,8 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
 
 	nres = 0;
 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
-		bars |= (1 << (i + PCI_IOV_RESOURCES));
-		res = &dev->resource[i + PCI_IOV_RESOURCES];
+		bars |= (1 << pci_resource_to_iov(i));
+		res = &dev->resource[pci_resource_to_iov(i)];
 		if (res->parent)
 			nres++;
 	}
@@ -786,8 +786,8 @@ static int sriov_init(struct pci_dev *dev, int pos)
 
 	nres = 0;
 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
-		res = &dev->resource[i + PCI_IOV_RESOURCES];
-		res_name = pci_resource_name(dev, i + PCI_IOV_RESOURCES);
+		res = &dev->resource[pci_resource_to_iov(i)];
+		res_name = pci_resource_name(dev, pci_resource_to_iov(i));
 
 		/*
 		 * If it is already FIXED, don't change it, something
@@ -844,7 +844,7 @@ static int sriov_init(struct pci_dev *dev, int pos)
 	dev->is_physfn = 0;
 failed:
 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
-		res = &dev->resource[i + PCI_IOV_RESOURCES];
+		res = &dev->resource[pci_resource_to_iov(i)];
 		res->flags = 0;
 	}
 
@@ -906,7 +906,7 @@ static void sriov_restore_state(struct pci_dev *dev)
 	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
 
 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
-		pci_update_resource(dev, i + PCI_IOV_RESOURCES);
+		pci_update_resource(dev, pci_resource_to_iov(i));
 
 	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
 	pci_iov_set_numvfs(dev, iov->num_VFs);
@@ -972,7 +972,7 @@ void pci_iov_update_resource(struct pci_dev *dev, int resno)
 {
 	struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
 	struct resource *res = dev->resource + resno;
-	int vf_bar = resno - PCI_IOV_RESOURCES;
+	int vf_bar = pci_resource_from_iov(resno);
 	struct pci_bus_region region;
 	u16 cmd;
 	u32 new;
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 48d345607e57e..1f8d88f0243b7 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -584,6 +584,15 @@ static inline bool pci_resource_is_iov(int resno)
 {
 	return resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END;
 }
+static inline int pci_resource_to_iov(int resno)
+{
+	return resno + PCI_IOV_RESOURCES;
+}
+
+static inline int pci_resource_from_iov(int resno)
+{
+	return resno - PCI_IOV_RESOURCES;
+}
 extern const struct attribute_group sriov_pf_dev_attr_group;
 extern const struct attribute_group sriov_vf_dev_attr_group;
 #else
@@ -608,6 +617,15 @@ static inline bool pci_resource_is_iov(int resno)
 {
 	return false;
 }
+static inline int pci_resource_to_iov(int resno)
+{
+	return -ENODEV;
+}
+
+static inline int pci_resource_from_iov(int resno)
+{
+	return -ENODEV;
+}
 #endif /* CONFIG_PCI_IOV */
 
 #ifdef CONFIG_PCIE_PTM
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index ba293df10c050..c5ad7c4ad6eb1 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1778,7 +1778,7 @@ static int iov_resources_unassigned(struct pci_dev *dev, void *data)
 	bool *unassigned = data;
 
 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
-		struct resource *r = &dev->resource[i + PCI_IOV_RESOURCES];
+		struct resource *r = &dev->resource[pci_resource_to_iov(i)];
 		struct pci_bus_region region;
 
 		/* Not assigned or rejected by kernel? */
-- 
2.47.0
Re: [PATCH v4 3/7] PCI: Add a helper to convert between standard and IOV resources
Posted by Ilpo Järvinen 1 year, 3 months ago 
On Fri, 25 Oct 2024, Michał Winiarski wrote:

> There are multiple places where conversions between IOV resources and
> standard resources are done.
> 
> Extract the logic to pci_resource_to_iov() and pci_resource_from_iov()
> helpers.
> 
> Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
> ---
>  drivers/pci/iov.c       | 20 ++++++++++----------
>  drivers/pci/pci.h       | 18 ++++++++++++++++++
>  drivers/pci/setup-bus.c |  2 +-
>  3 files changed, 29 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
> index 6bdc9950b9787..eedc1df56c49e 100644
> --- a/drivers/pci/iov.c
> +++ b/drivers/pci/iov.c
> @@ -151,7 +151,7 @@ resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
>  	if (!dev->is_physfn)
>  		return 0;
>  
> -	return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
> +	return dev->sriov->barsz[pci_resource_from_iov(resno)];
>  }
>  
>  static void pci_read_vf_config_common(struct pci_dev *virtfn)
> @@ -322,12 +322,12 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id)
>  	virtfn->multifunction = 0;
>  
>  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> +		res = &dev->resource[pci_resource_to_iov(i)];
>  		if (!res->parent)
>  			continue;
>  		virtfn->resource[i].name = pci_name(virtfn);
>  		virtfn->resource[i].flags = res->flags;
> -		size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
> +		size = pci_iov_resource_size(dev, pci_resource_to_iov(i));
>  		virtfn->resource[i].start = res->start + size * id;
>  		virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
>  		rc = request_resource(res, &virtfn->resource[i]);
> @@ -624,8 +624,8 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
>  
>  	nres = 0;
>  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		bars |= (1 << (i + PCI_IOV_RESOURCES));
> -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> +		bars |= (1 << pci_resource_to_iov(i));
> +		res = &dev->resource[pci_resource_to_iov(i)];
>  		if (res->parent)
>  			nres++;
>  	}
> @@ -786,8 +786,8 @@ static int sriov_init(struct pci_dev *dev, int pos)
>  
>  	nres = 0;
>  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> -		res_name = pci_resource_name(dev, i + PCI_IOV_RESOURCES);
> +		res = &dev->resource[pci_resource_to_iov(i)];
> +		res_name = pci_resource_name(dev, pci_resource_to_iov(i));
>  
>  		/*
>  		 * If it is already FIXED, don't change it, something
> @@ -844,7 +844,7 @@ static int sriov_init(struct pci_dev *dev, int pos)
>  	dev->is_physfn = 0;
>  failed:
>  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> +		res = &dev->resource[pci_resource_to_iov(i)];
>  		res->flags = 0;
>  	}
>  
> @@ -906,7 +906,7 @@ static void sriov_restore_state(struct pci_dev *dev)
>  	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
>  
>  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
> -		pci_update_resource(dev, i + PCI_IOV_RESOURCES);
> +		pci_update_resource(dev, pci_resource_to_iov(i));
>  
>  	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
>  	pci_iov_set_numvfs(dev, iov->num_VFs);
> @@ -972,7 +972,7 @@ void pci_iov_update_resource(struct pci_dev *dev, int resno)
>  {
>  	struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
>  	struct resource *res = dev->resource + resno;
> -	int vf_bar = resno - PCI_IOV_RESOURCES;
> +	int vf_bar = pci_resource_from_iov(resno);
>  	struct pci_bus_region region;
>  	u16 cmd;
>  	u32 new;
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 48d345607e57e..1f8d88f0243b7 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -584,6 +584,15 @@ static inline bool pci_resource_is_iov(int resno)
>  {
>  	return resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END;
>  }
> +static inline int pci_resource_to_iov(int resno)
> +{
> +	return resno + PCI_IOV_RESOURCES;
> +}
> +
> +static inline int pci_resource_from_iov(int resno)
> +{
> +	return resno - PCI_IOV_RESOURCES;
> +}

to/from feels wrong way around for me. What is named as "PCI resource from 
IOV" converts from PCI resource indexing to IOV compatible indexing, and 
vice versa.

>  extern const struct attribute_group sriov_pf_dev_attr_group;
>  extern const struct attribute_group sriov_vf_dev_attr_group;
>  #else
> @@ -608,6 +617,15 @@ static inline bool pci_resource_is_iov(int resno)
>  {
>  	return false;
>  }
> +static inline int pci_resource_to_iov(int resno)
> +{
> +	return -ENODEV;
> +}
> +
> +static inline int pci_resource_from_iov(int resno)
> +{
> +	return -ENODEV;
> +}

These seem dangerous as the errors are not checked by the callers. Perhaps 
put something like BUG_ON(1) there instead as it really is something that 
should never be called for real if CONFIG_PCI_IOV is not enabled, they are 
just to make compiler happy without #ifdefs in C code.

-- 
 i.

>  #endif /* CONFIG_PCI_IOV */
>  
>  #ifdef CONFIG_PCIE_PTM
> diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
> index ba293df10c050..c5ad7c4ad6eb1 100644
> --- a/drivers/pci/setup-bus.c
> +++ b/drivers/pci/setup-bus.c
> @@ -1778,7 +1778,7 @@ static int iov_resources_unassigned(struct pci_dev *dev, void *data)
>  	bool *unassigned = data;
>  
>  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		struct resource *r = &dev->resource[i + PCI_IOV_RESOURCES];
> +		struct resource *r = &dev->resource[pci_resource_to_iov(i)];
>  		struct pci_bus_region region;
>  
>  		/* Not assigned or rejected by kernel? */
>
Re: [PATCH v4 3/7] PCI: Add a helper to convert between standard and IOV resources
Posted by Michał Winiarski 1 year, 2 months ago 
On Wed, Nov 06, 2024 at 04:22:11PM +0200, Ilpo Järvinen wrote:
> On Fri, 25 Oct 2024, Michał Winiarski wrote:
> 
> > There are multiple places where conversions between IOV resources and
> > standard resources are done.
> > 
> > Extract the logic to pci_resource_to_iov() and pci_resource_from_iov()
> > helpers.
> > 
> > Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> > Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
> > ---
> >  drivers/pci/iov.c       | 20 ++++++++++----------
> >  drivers/pci/pci.h       | 18 ++++++++++++++++++
> >  drivers/pci/setup-bus.c |  2 +-
> >  3 files changed, 29 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
> > index 6bdc9950b9787..eedc1df56c49e 100644
> > --- a/drivers/pci/iov.c
> > +++ b/drivers/pci/iov.c
> > @@ -151,7 +151,7 @@ resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
> >  	if (!dev->is_physfn)
> >  		return 0;
> >  
> > -	return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
> > +	return dev->sriov->barsz[pci_resource_from_iov(resno)];
> >  }
> >  
> >  static void pci_read_vf_config_common(struct pci_dev *virtfn)
> > @@ -322,12 +322,12 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id)
> >  	virtfn->multifunction = 0;
> >  
> >  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> > -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> > +		res = &dev->resource[pci_resource_to_iov(i)];
> >  		if (!res->parent)
> >  			continue;
> >  		virtfn->resource[i].name = pci_name(virtfn);
> >  		virtfn->resource[i].flags = res->flags;
> > -		size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
> > +		size = pci_iov_resource_size(dev, pci_resource_to_iov(i));
> >  		virtfn->resource[i].start = res->start + size * id;
> >  		virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
> >  		rc = request_resource(res, &virtfn->resource[i]);
> > @@ -624,8 +624,8 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> >  
> >  	nres = 0;
> >  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> > -		bars |= (1 << (i + PCI_IOV_RESOURCES));
> > -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> > +		bars |= (1 << pci_resource_to_iov(i));
> > +		res = &dev->resource[pci_resource_to_iov(i)];
> >  		if (res->parent)
> >  			nres++;
> >  	}
> > @@ -786,8 +786,8 @@ static int sriov_init(struct pci_dev *dev, int pos)
> >  
> >  	nres = 0;
> >  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> > -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> > -		res_name = pci_resource_name(dev, i + PCI_IOV_RESOURCES);
> > +		res = &dev->resource[pci_resource_to_iov(i)];
> > +		res_name = pci_resource_name(dev, pci_resource_to_iov(i));
> >  
> >  		/*
> >  		 * If it is already FIXED, don't change it, something
> > @@ -844,7 +844,7 @@ static int sriov_init(struct pci_dev *dev, int pos)
> >  	dev->is_physfn = 0;
> >  failed:
> >  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> > -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> > +		res = &dev->resource[pci_resource_to_iov(i)];
> >  		res->flags = 0;
> >  	}
> >  
> > @@ -906,7 +906,7 @@ static void sriov_restore_state(struct pci_dev *dev)
> >  	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
> >  
> >  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
> > -		pci_update_resource(dev, i + PCI_IOV_RESOURCES);
> > +		pci_update_resource(dev, pci_resource_to_iov(i));
> >  
> >  	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
> >  	pci_iov_set_numvfs(dev, iov->num_VFs);
> > @@ -972,7 +972,7 @@ void pci_iov_update_resource(struct pci_dev *dev, int resno)
> >  {
> >  	struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
> >  	struct resource *res = dev->resource + resno;
> > -	int vf_bar = resno - PCI_IOV_RESOURCES;
> > +	int vf_bar = pci_resource_from_iov(resno);
> >  	struct pci_bus_region region;
> >  	u16 cmd;
> >  	u32 new;
> > diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> > index 48d345607e57e..1f8d88f0243b7 100644
> > --- a/drivers/pci/pci.h
> > +++ b/drivers/pci/pci.h
> > @@ -584,6 +584,15 @@ static inline bool pci_resource_is_iov(int resno)
> >  {
> >  	return resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END;
> >  }
> > +static inline int pci_resource_to_iov(int resno)
> > +{
> > +	return resno + PCI_IOV_RESOURCES;
> > +}
> > +
> > +static inline int pci_resource_from_iov(int resno)
> > +{
> > +	return resno - PCI_IOV_RESOURCES;
> > +}
> 
> to/from feels wrong way around for me. What is named as "PCI resource from 
> IOV" converts from PCI resource indexing to IOV compatible indexing, and 
> vice versa.

It converts "from" IOV BAR (resource 7+) to VF BAR (resource 0+).
I don't think swapping the to/from would make it clearer.

I had it as pci_iov_resource_to_vf_bar() / pci_vf_bar_to_iov_resource()
before, but went with a shorter naming instead.
Would that be clearer?
pci_iov_resource_to_vf_bar() / pci_iov_resource_from_vf_bar()?
Or perhaps you have a better suggestion?

> 
> >  extern const struct attribute_group sriov_pf_dev_attr_group;
> >  extern const struct attribute_group sriov_vf_dev_attr_group;
> >  #else
> > @@ -608,6 +617,15 @@ static inline bool pci_resource_is_iov(int resno)
> >  {
> >  	return false;
> >  }
> > +static inline int pci_resource_to_iov(int resno)
> > +{
> > +	return -ENODEV;
> > +}
> > +
> > +static inline int pci_resource_from_iov(int resno)
> > +{
> > +	return -ENODEV;
> > +}
> 
> These seem dangerous as the errors are not checked by the callers. Perhaps 
> put something like BUG_ON(1) there instead as it really is something that 
> should never be called for real if CONFIG_PCI_IOV is not enabled, they are 
> just to make compiler happy without #ifdefs in C code.

I'll add a WARN_ON_ONCE(1) to make it more visible.

-Michał

> 
> -- 
>  i.
> 
> >  #endif /* CONFIG_PCI_IOV */
> >  
> >  #ifdef CONFIG_PCIE_PTM
> > diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
> > index ba293df10c050..c5ad7c4ad6eb1 100644
> > --- a/drivers/pci/setup-bus.c
> > +++ b/drivers/pci/setup-bus.c
> > @@ -1778,7 +1778,7 @@ static int iov_resources_unassigned(struct pci_dev *dev, void *data)
> >  	bool *unassigned = data;
> >  
> >  	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> > -		struct resource *r = &dev->resource[i + PCI_IOV_RESOURCES];
> > +		struct resource *r = &dev->resource[pci_resource_to_iov(i)];
> >  		struct pci_bus_region region;
> >  
> >  		/* Not assigned or rejected by kernel? */
> >
Re: [PATCH v4 3/7] PCI: Add a helper to convert between standard and IOV resources
Posted by Christian König 1 year, 3 months ago 
Am 25.10.24 um 23:50 schrieb Michał Winiarski:
> There are multiple places where conversions between IOV resources and
> standard resources are done.
>
> Extract the logic to pci_resource_to_iov() and pci_resource_from_iov()
> helpers.
>
> Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>

I don't work enough with that code to fully judge if that is useful or not.

But feel free to add Acked-by: Christian König 
<christian.koenig@amd.com> since style etc.. looks good to me.

Regards,
Christian.

> ---
>   drivers/pci/iov.c       | 20 ++++++++++----------
>   drivers/pci/pci.h       | 18 ++++++++++++++++++
>   drivers/pci/setup-bus.c |  2 +-
>   3 files changed, 29 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
> index 6bdc9950b9787..eedc1df56c49e 100644
> --- a/drivers/pci/iov.c
> +++ b/drivers/pci/iov.c
> @@ -151,7 +151,7 @@ resource_size_t pci_iov_resource_size(struct pci_dev *dev, int resno)
>   	if (!dev->is_physfn)
>   		return 0;
>   
> -	return dev->sriov->barsz[resno - PCI_IOV_RESOURCES];
> +	return dev->sriov->barsz[pci_resource_from_iov(resno)];
>   }
>   
>   static void pci_read_vf_config_common(struct pci_dev *virtfn)
> @@ -322,12 +322,12 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id)
>   	virtfn->multifunction = 0;
>   
>   	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> +		res = &dev->resource[pci_resource_to_iov(i)];
>   		if (!res->parent)
>   			continue;
>   		virtfn->resource[i].name = pci_name(virtfn);
>   		virtfn->resource[i].flags = res->flags;
> -		size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
> +		size = pci_iov_resource_size(dev, pci_resource_to_iov(i));
>   		virtfn->resource[i].start = res->start + size * id;
>   		virtfn->resource[i].end = virtfn->resource[i].start + size - 1;
>   		rc = request_resource(res, &virtfn->resource[i]);
> @@ -624,8 +624,8 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
>   
>   	nres = 0;
>   	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		bars |= (1 << (i + PCI_IOV_RESOURCES));
> -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> +		bars |= (1 << pci_resource_to_iov(i));
> +		res = &dev->resource[pci_resource_to_iov(i)];
>   		if (res->parent)
>   			nres++;
>   	}
> @@ -786,8 +786,8 @@ static int sriov_init(struct pci_dev *dev, int pos)
>   
>   	nres = 0;
>   	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> -		res_name = pci_resource_name(dev, i + PCI_IOV_RESOURCES);
> +		res = &dev->resource[pci_resource_to_iov(i)];
> +		res_name = pci_resource_name(dev, pci_resource_to_iov(i));
>   
>   		/*
>   		 * If it is already FIXED, don't change it, something
> @@ -844,7 +844,7 @@ static int sriov_init(struct pci_dev *dev, int pos)
>   	dev->is_physfn = 0;
>   failed:
>   	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		res = &dev->resource[i + PCI_IOV_RESOURCES];
> +		res = &dev->resource[pci_resource_to_iov(i)];
>   		res->flags = 0;
>   	}
>   
> @@ -906,7 +906,7 @@ static void sriov_restore_state(struct pci_dev *dev)
>   	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, ctrl);
>   
>   	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++)
> -		pci_update_resource(dev, i + PCI_IOV_RESOURCES);
> +		pci_update_resource(dev, pci_resource_to_iov(i));
>   
>   	pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz);
>   	pci_iov_set_numvfs(dev, iov->num_VFs);
> @@ -972,7 +972,7 @@ void pci_iov_update_resource(struct pci_dev *dev, int resno)
>   {
>   	struct pci_sriov *iov = dev->is_physfn ? dev->sriov : NULL;
>   	struct resource *res = dev->resource + resno;
> -	int vf_bar = resno - PCI_IOV_RESOURCES;
> +	int vf_bar = pci_resource_from_iov(resno);
>   	struct pci_bus_region region;
>   	u16 cmd;
>   	u32 new;
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 48d345607e57e..1f8d88f0243b7 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -584,6 +584,15 @@ static inline bool pci_resource_is_iov(int resno)
>   {
>   	return resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END;
>   }
> +static inline int pci_resource_to_iov(int resno)
> +{
> +	return resno + PCI_IOV_RESOURCES;
> +}
> +
> +static inline int pci_resource_from_iov(int resno)
> +{
> +	return resno - PCI_IOV_RESOURCES;
> +}
>   extern const struct attribute_group sriov_pf_dev_attr_group;
>   extern const struct attribute_group sriov_vf_dev_attr_group;
>   #else
> @@ -608,6 +617,15 @@ static inline bool pci_resource_is_iov(int resno)
>   {
>   	return false;
>   }
> +static inline int pci_resource_to_iov(int resno)
> +{
> +	return -ENODEV;
> +}
> +
> +static inline int pci_resource_from_iov(int resno)
> +{
> +	return -ENODEV;
> +}
>   #endif /* CONFIG_PCI_IOV */
>   
>   #ifdef CONFIG_PCIE_PTM
> diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
> index ba293df10c050..c5ad7c4ad6eb1 100644
> --- a/drivers/pci/setup-bus.c
> +++ b/drivers/pci/setup-bus.c
> @@ -1778,7 +1778,7 @@ static int iov_resources_unassigned(struct pci_dev *dev, void *data)
>   	bool *unassigned = data;
>   
>   	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
> -		struct resource *r = &dev->resource[i + PCI_IOV_RESOURCES];
> +		struct resource *r = &dev->resource[pci_resource_to_iov(i)];
>   		struct pci_bus_region region;
>   
>   		/* Not assigned or rejected by kernel? */

Patchew 2.1-devel-b67e4c2

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