[PATCH 1/2] PCI: Deprecate pcim_iomap_regions() in favor of pcim_iomap_region()

[PATCH 1/2] PCI: Deprecate pcim_iomap_regions() in favor of pcim_iomap_region()

[Philipp Stanner]

pcim_iomap_regions() is a complicated function that uses a bit mask to
determine the BARs the user wishes to request and ioremap. Almost all
users only ever set a single bit in that mask, making that mechanism
questionable.

pcim_iomap_region() is now available as a more simple replacement.

Make pcim_iomap_region() a public function.

Mark pcim_iomap_regions() as deprecated.

Signed-off-by: Philipp Stanner <pstanner@redhat.com>
---
 drivers/pci/devres.c | 8 ++++++--
 include/linux/pci.h  | 2 ++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c
index 3780a9f9ec00..89ec26ea1501 100644
--- a/drivers/pci/devres.c
+++ b/drivers/pci/devres.c
@@ -728,7 +728,7 @@ EXPORT_SYMBOL(pcim_iounmap);
  * Mapping and region will get automatically released on driver detach. If
  * desired, release manually only with pcim_iounmap_region().
  */
-static void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
+void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
 				       const char *name)
 {
 	int ret;
@@ -761,6 +761,7 @@ static void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
 
 	return IOMEM_ERR_PTR(ret);
 }
+EXPORT_SYMBOL(pcim_iomap_region);
 
 /**
  * pcim_iounmap_region - Unmap and release a PCI BAR
@@ -783,7 +784,7 @@ static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
 }
 
 /**
- * pcim_iomap_regions - Request and iomap PCI BARs
+ * pcim_iomap_regions - Request and iomap PCI BARs (DEPRECATED)
  * @pdev: PCI device to map IO resources for
  * @mask: Mask of BARs to request and iomap
  * @name: Name associated with the requests
@@ -791,6 +792,9 @@ static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
  * Returns: 0 on success, negative error code on failure.
  *
  * Request and iomap regions specified by @mask.
+ *
+ * This function is DEPRECATED. Do not use it in new code.
+ * Use pcim_iomap_region() instead.
  */
 int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name)
 {
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 4cf89a4b4cbc..fc30176d28ca 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -2292,6 +2292,8 @@ static inline void pci_fixup_device(enum pci_fixup_pass pass,
 void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen);
 void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr);
 void __iomem * const *pcim_iomap_table(struct pci_dev *pdev);
+void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
+				       const char *name);
 int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name);
 int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask,
 				   const char *name);
-- 
2.45.2

[PATCH 2/2] drm/ast: Request PCI BAR with devres

[Philipp Stanner]

ast currently ioremaps two PCI BARs using pcim_iomap(). It does not
perform a request on the regions, however, which would make the driver a
bit more robust.

PCI now offers pcim_iomap_region(), a managed function which both
requests and ioremaps a BAR.

Replace pcim_iomap() with pcim_iomap_region().

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
---
 drivers/gpu/drm/ast/ast_drv.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_drv.c b/drivers/gpu/drm/ast/ast_drv.c
index aae019e79bda..1fadaadfbe39 100644
--- a/drivers/gpu/drm/ast/ast_drv.c
+++ b/drivers/gpu/drm/ast/ast_drv.c
@@ -287,9 +287,9 @@ static int ast_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (ret)
 		return ret;
 
-	regs = pcim_iomap(pdev, 1, 0);
-	if (!regs)
-		return -EIO;
+	regs = pcim_iomap_region(pdev, 1, "ast");
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
 
 	if (pdev->revision >= 0x40) {
 		/*
@@ -311,9 +311,9 @@ static int ast_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 		if (len < AST_IO_MM_LENGTH)
 			return -EIO;
-		ioregs = pcim_iomap(pdev, 2, 0);
-		if (!ioregs)
-			return -EIO;
+		ioregs = pcim_iomap_region(pdev, 2, "ast");
+		if (IS_ERR(ioregs))
+			return PTR_ERR(ioregs);
 	} else {
 		/*
 		 * Anything else is best effort.
-- 
2.45.2

Re: [PATCH 2/2] drm/ast: Request PCI BAR with devres

[Thomas Zimmermann]

Am 07.08.24 um 10:30 schrieb Philipp Stanner:
> ast currently ioremaps two PCI BARs using pcim_iomap(). It does not
> perform a request on the regions, however, which would make the driver a
> bit more robust.
>
> PCI now offers pcim_iomap_region(), a managed function which both
> requests and ioremaps a BAR.
>
> Replace pcim_iomap() with pcim_iomap_region().
>
> Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
> Signed-off-by: Philipp Stanner <pstanner@redhat.com>

Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>

> ---
>   drivers/gpu/drm/ast/ast_drv.c | 12 ++++++------
>   1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/ast/ast_drv.c b/drivers/gpu/drm/ast/ast_drv.c
> index aae019e79bda..1fadaadfbe39 100644
> --- a/drivers/gpu/drm/ast/ast_drv.c
> +++ b/drivers/gpu/drm/ast/ast_drv.c
> @@ -287,9 +287,9 @@ static int ast_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>   	if (ret)
>   		return ret;
>   
> -	regs = pcim_iomap(pdev, 1, 0);
> -	if (!regs)
> -		return -EIO;
> +	regs = pcim_iomap_region(pdev, 1, "ast");
> +	if (IS_ERR(regs))
> +		return PTR_ERR(regs);
>   
>   	if (pdev->revision >= 0x40) {
>   		/*
> @@ -311,9 +311,9 @@ static int ast_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>   
>   		if (len < AST_IO_MM_LENGTH)
>   			return -EIO;
> -		ioregs = pcim_iomap(pdev, 2, 0);
> -		if (!ioregs)
> -			return -EIO;
> +		ioregs = pcim_iomap_region(pdev, 2, "ast");
> +		if (IS_ERR(ioregs))
> +			return PTR_ERR(ioregs);
>   	} else {
>   		/*
>   		 * Anything else is best effort.

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

Re: [PATCH 1/2] PCI: Deprecate pcim_iomap_regions() in favor of pcim_iomap_region()

[Bjorn Helgaas]

On Wed, Aug 07, 2024 at 10:30:18AM +0200, Philipp Stanner wrote:
> pcim_iomap_regions() is a complicated function that uses a bit mask to
> determine the BARs the user wishes to request and ioremap. Almost all
> users only ever set a single bit in that mask, making that mechanism
> questionable.
> 
> pcim_iomap_region() is now available as a more simple replacement.
> 
> Make pcim_iomap_region() a public function.
> 
> Mark pcim_iomap_regions() as deprecated.
> 
> Signed-off-by: Philipp Stanner <pstanner@redhat.com>

The interesting part of this little series is in ast_drv.c, but there
may be similar conversions for other drivers coming as well.

To avoid races during the merge window, I propose merging this via the
PCI tree so I can ensure that any other conversions happen after
pcim_iomap_region() becomes public.

That would require an ack from Dave.  But if you'd rather take this
yourself, Dave, here's my ack for the PCI piece:

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

> ---
>  drivers/pci/devres.c | 8 ++++++--
>  include/linux/pci.h  | 2 ++
>  2 files changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c
> index 3780a9f9ec00..89ec26ea1501 100644
> --- a/drivers/pci/devres.c
> +++ b/drivers/pci/devres.c
> @@ -728,7 +728,7 @@ EXPORT_SYMBOL(pcim_iounmap);
>   * Mapping and region will get automatically released on driver detach. If
>   * desired, release manually only with pcim_iounmap_region().
>   */
> -static void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
> +void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
>  				       const char *name)
>  {
>  	int ret;
> @@ -761,6 +761,7 @@ static void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
>  
>  	return IOMEM_ERR_PTR(ret);
>  }
> +EXPORT_SYMBOL(pcim_iomap_region);
>  
>  /**
>   * pcim_iounmap_region - Unmap and release a PCI BAR
> @@ -783,7 +784,7 @@ static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
>  }
>  
>  /**
> - * pcim_iomap_regions - Request and iomap PCI BARs
> + * pcim_iomap_regions - Request and iomap PCI BARs (DEPRECATED)
>   * @pdev: PCI device to map IO resources for
>   * @mask: Mask of BARs to request and iomap
>   * @name: Name associated with the requests
> @@ -791,6 +792,9 @@ static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
>   * Returns: 0 on success, negative error code on failure.
>   *
>   * Request and iomap regions specified by @mask.
> + *
> + * This function is DEPRECATED. Do not use it in new code.
> + * Use pcim_iomap_region() instead.
>   */
>  int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name)
>  {
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 4cf89a4b4cbc..fc30176d28ca 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -2292,6 +2292,8 @@ static inline void pci_fixup_device(enum pci_fixup_pass pass,
>  void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen);
>  void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr);
>  void __iomem * const *pcim_iomap_table(struct pci_dev *pdev);
> +void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
> +				       const char *name);
>  int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name);
>  int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask,
>  				   const char *name);
> -- 
> 2.45.2
> 

Re: [PATCH 1/2] PCI: Deprecate pcim_iomap_regions() in favor of pcim_iomap_region()

[David Airlie]

On Thu, Aug 8, 2024 at 6:33 AM Bjorn Helgaas <helgaas@kernel.org> wrote:
>
> On Wed, Aug 07, 2024 at 10:30:18AM +0200, Philipp Stanner wrote:
> > pcim_iomap_regions() is a complicated function that uses a bit mask to
> > determine the BARs the user wishes to request and ioremap. Almost all
> > users only ever set a single bit in that mask, making that mechanism
> > questionable.
> >
> > pcim_iomap_region() is now available as a more simple replacement.
> >
> > Make pcim_iomap_region() a public function.
> >
> > Mark pcim_iomap_regions() as deprecated.
> >
> > Signed-off-by: Philipp Stanner <pstanner@redhat.com>
>
> The interesting part of this little series is in ast_drv.c, but there
> may be similar conversions for other drivers coming as well.
>
> To avoid races during the merge window, I propose merging this via the
> PCI tree so I can ensure that any other conversions happen after
> pcim_iomap_region() becomes public.
>
> That would require an ack from Dave.  But if you'd rather take this
> yourself, Dave, here's my ack for the PCI piece:
>
> Acked-by: Bjorn Helgaas <bhelgaas@google.com>

I'm fine with it going in via pci.

Acked-by: Dave Airlie <airlied@redhat.com>

Dave.

>
> > ---
> >  drivers/pci/devres.c | 8 ++++++--
> >  include/linux/pci.h  | 2 ++
> >  2 files changed, 8 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c
> > index 3780a9f9ec00..89ec26ea1501 100644
> > --- a/drivers/pci/devres.c
> > +++ b/drivers/pci/devres.c
> > @@ -728,7 +728,7 @@ EXPORT_SYMBOL(pcim_iounmap);
> >   * Mapping and region will get automatically released on driver detach. If
> >   * desired, release manually only with pcim_iounmap_region().
> >   */
> > -static void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
> > +void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
> >                                      const char *name)
> >  {
> >       int ret;
> > @@ -761,6 +761,7 @@ static void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
> >
> >       return IOMEM_ERR_PTR(ret);
> >  }
> > +EXPORT_SYMBOL(pcim_iomap_region);
> >
> >  /**
> >   * pcim_iounmap_region - Unmap and release a PCI BAR
> > @@ -783,7 +784,7 @@ static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
> >  }
> >
> >  /**
> > - * pcim_iomap_regions - Request and iomap PCI BARs
> > + * pcim_iomap_regions - Request and iomap PCI BARs (DEPRECATED)
> >   * @pdev: PCI device to map IO resources for
> >   * @mask: Mask of BARs to request and iomap
> >   * @name: Name associated with the requests
> > @@ -791,6 +792,9 @@ static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
> >   * Returns: 0 on success, negative error code on failure.
> >   *
> >   * Request and iomap regions specified by @mask.
> > + *
> > + * This function is DEPRECATED. Do not use it in new code.
> > + * Use pcim_iomap_region() instead.
> >   */
> >  int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name)
> >  {
> > diff --git a/include/linux/pci.h b/include/linux/pci.h
> > index 4cf89a4b4cbc..fc30176d28ca 100644
> > --- a/include/linux/pci.h
> > +++ b/include/linux/pci.h
> > @@ -2292,6 +2292,8 @@ static inline void pci_fixup_device(enum pci_fixup_pass pass,
> >  void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen);
> >  void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr);
> >  void __iomem * const *pcim_iomap_table(struct pci_dev *pdev);
> > +void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
> > +                                    const char *name);
> >  int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name);
> >  int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask,
> >                                  const char *name);
> > --
> > 2.45.2
> >
>

Re: [PATCH 1/2] PCI: Deprecate pcim_iomap_regions() in favor of pcim_iomap_region()

[Bjorn Helgaas]

On Wed, Aug 07, 2024 at 10:30:18AM +0200, Philipp Stanner wrote:
> pcim_iomap_regions() is a complicated function that uses a bit mask to
> determine the BARs the user wishes to request and ioremap. Almost all
> users only ever set a single bit in that mask, making that mechanism
> questionable.
> 
> pcim_iomap_region() is now available as a more simple replacement.
> 
> Make pcim_iomap_region() a public function.
> 
> Mark pcim_iomap_regions() as deprecated.
> 
> Signed-off-by: Philipp Stanner <pstanner@redhat.com>

Both applied (second with Thomas' reviewed-by and Dave's ack) to
pci/devres for v6.12, thanks!

> ---
>  drivers/pci/devres.c | 8 ++++++--
>  include/linux/pci.h  | 2 ++
>  2 files changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c
> index 3780a9f9ec00..89ec26ea1501 100644
> --- a/drivers/pci/devres.c
> +++ b/drivers/pci/devres.c
> @@ -728,7 +728,7 @@ EXPORT_SYMBOL(pcim_iounmap);
>   * Mapping and region will get automatically released on driver detach. If
>   * desired, release manually only with pcim_iounmap_region().
>   */
> -static void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
> +void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
>  				       const char *name)
>  {
>  	int ret;
> @@ -761,6 +761,7 @@ static void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
>  
>  	return IOMEM_ERR_PTR(ret);
>  }
> +EXPORT_SYMBOL(pcim_iomap_region);
>  
>  /**
>   * pcim_iounmap_region - Unmap and release a PCI BAR
> @@ -783,7 +784,7 @@ static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
>  }
>  
>  /**
> - * pcim_iomap_regions - Request and iomap PCI BARs
> + * pcim_iomap_regions - Request and iomap PCI BARs (DEPRECATED)
>   * @pdev: PCI device to map IO resources for
>   * @mask: Mask of BARs to request and iomap
>   * @name: Name associated with the requests
> @@ -791,6 +792,9 @@ static void pcim_iounmap_region(struct pci_dev *pdev, int bar)
>   * Returns: 0 on success, negative error code on failure.
>   *
>   * Request and iomap regions specified by @mask.
> + *
> + * This function is DEPRECATED. Do not use it in new code.
> + * Use pcim_iomap_region() instead.
>   */
>  int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name)
>  {
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 4cf89a4b4cbc..fc30176d28ca 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -2292,6 +2292,8 @@ static inline void pci_fixup_device(enum pci_fixup_pass pass,
>  void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen);
>  void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr);
>  void __iomem * const *pcim_iomap_table(struct pci_dev *pdev);
> +void __iomem *pcim_iomap_region(struct pci_dev *pdev, int bar,
> +				       const char *name);
>  int pcim_iomap_regions(struct pci_dev *pdev, int mask, const char *name);
>  int pcim_iomap_regions_request_all(struct pci_dev *pdev, int mask,
>  				   const char *name);
> -- 
> 2.45.2
>