The patch turns pci_resource_to_user() to a weak function. Thus,
architecture-specific versions will automatically override the generic
one. This allows to remove the HAVE_ARCH_PCI_RESOURCE_TO_USER macro and
avoid the conditional compilation for this single function.
Signed-off-by: Denis Efremov <[email protected]>
---
drivers/pci/pci.c | 8 ++++++++
include/linux/pci.h | 18 +++---------------
2 files changed, 11 insertions(+), 15 deletions(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 29ed5ec1ac27..f9dc7563a8b9 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5932,6 +5932,14 @@ resource_size_t __weak pcibios_default_alignment(void)
return 0;
}
+void __weak pci_resource_to_user(const struct pci_dev *dev, int bar,
+ const struct resource *rsrc, resource_size_t *start,
+ resource_size_t *end)
+{
+ *start = rsrc->start;
+ *end = rsrc->end;
+}
+
#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
static DEFINE_SPINLOCK(resource_alignment_lock);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 9e700d9f9f28..1a19d0151b0a 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1870,25 +1870,13 @@ static inline const char *pci_name(const struct pci_dev *pdev)
return dev_name(&pdev->dev);
}
-
/*
* Some archs don't want to expose struct resource to userland as-is
* in sysfs and /proc
*/
-#ifdef HAVE_ARCH_PCI_RESOURCE_TO_USER
-void pci_resource_to_user(const struct pci_dev *dev, int bar,
- const struct resource *rsrc,
- resource_size_t *start, resource_size_t *end);
-#else
-static inline void pci_resource_to_user(const struct pci_dev *dev, int bar,
- const struct resource *rsrc, resource_size_t *start,
- resource_size_t *end)
-{
- *start = rsrc->start;
- *end = rsrc->end;
-}
-#endif /* HAVE_ARCH_PCI_RESOURCE_TO_USER */
-
+void __weak pci_resource_to_user(const struct pci_dev *dev, int bar,
+ const struct resource *rsrc,
+ resource_size_t *start, resource_size_t *end);
/*
* The world is not perfect and supplies us with broken PCI devices.
--
2.21.0
Hi Denis,
On Sun, Jul 28, 2019 at 11:22:09PM +0300, Denis Efremov wrote:
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 9e700d9f9f28..1a19d0151b0a 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1870,25 +1870,13 @@ static inline const char *pci_name(const struct pci_dev *pdev)
> return dev_name(&pdev->dev);
> }
>
> -
> /*
> * Some archs don't want to expose struct resource to userland as-is
> * in sysfs and /proc
> */
> -#ifdef HAVE_ARCH_PCI_RESOURCE_TO_USER
> -void pci_resource_to_user(const struct pci_dev *dev, int bar,
> - const struct resource *rsrc,
> - resource_size_t *start, resource_size_t *end);
> -#else
> -static inline void pci_resource_to_user(const struct pci_dev *dev, int bar,
> - const struct resource *rsrc, resource_size_t *start,
> - resource_size_t *end)
> -{
> - *start = rsrc->start;
> - *end = rsrc->end;
> -}
> -#endif /* HAVE_ARCH_PCI_RESOURCE_TO_USER */
> -
> +void __weak pci_resource_to_user(const struct pci_dev *dev, int bar,
> + const struct resource *rsrc,
> + resource_size_t *start, resource_size_t *end);
>
> /*
> * The world is not perfect and supplies us with broken PCI devices.
This is wrong - using __weak on the declaration in a header will cause
the weak attribute to be applied to all implementations too (presuming
the C files containing the implementations include the header). You then
get whichever impleentation the linker chooses, which isn't necessarily
the one you wanted.
checkpatch.pl should produce an error about this - see the
WEAK_DECLARATION error introduced in commit 619a908aa334 ("checkpatch:
add error on use of attribute((weak)) or __weak declarations").
Thanks,
Paul
On Sun, 2019-07-28 at 22:49 +0000, Paul Burton wrote:
> Hi Denis,
>
> On Sun, Jul 28, 2019 at 11:22:09PM +0300, Denis Efremov wrote:
> > diff --git a/include/linux/pci.h b/include/linux/pci.h
> > index 9e700d9f9f28..1a19d0151b0a 100644
> > --- a/include/linux/pci.h
> > +++ b/include/linux/pci.h
> > @@ -1870,25 +1870,13 @@ static inline const char *pci_name(const struct pci_dev *pdev)
> > return dev_name(&pdev->dev);
> > }
> >
> > -
> > /*
> > * Some archs don't want to expose struct resource to userland as-is
> > * in sysfs and /proc
> > */
> > -#ifdef HAVE_ARCH_PCI_RESOURCE_TO_USER
> > -void pci_resource_to_user(const struct pci_dev *dev, int bar,
> > - const struct resource *rsrc,
> > - resource_size_t *start, resource_size_t *end);
> > -#else
> > -static inline void pci_resource_to_user(const struct pci_dev *dev, int bar,
> > - const struct resource *rsrc, resource_size_t *start,
> > - resource_size_t *end)
> > -{
> > - *start = rsrc->start;
> > - *end = rsrc->end;
> > -}
> > -#endif /* HAVE_ARCH_PCI_RESOURCE_TO_USER */
> > -
> > +void __weak pci_resource_to_user(const struct pci_dev *dev, int bar,
> > + const struct resource *rsrc,
> > + resource_size_t *start, resource_size_t *end);
> >
> > /*
> > * The world is not perfect and supplies us with broken PCI devices.
>
> This is wrong - using __weak on the declaration in a header will cause
> the weak attribute to be applied to all implementations too (presuming
> the C files containing the implementations include the header). You then
> get whichever impleentation the linker chooses, which isn't necessarily
> the one you wanted.
>
> checkpatch.pl should produce an error about this - see the
> WEAK_DECLARATION error introduced in commit 619a908aa334 ("checkpatch:
> add error on use of attribute((weak)) or __weak declarations").
Unfortunately, checkpatch is pretty stupid and only emits
this on single line declarations.
Hi Paul,
On 29.07.2019 01:49, Paul Burton wrote:
> Hi Denis,
>
> This is wrong - using __weak on the declaration in a header will cause
> the weak attribute to be applied to all implementations too (presuming
> the C files containing the implementations include the header). You then
> get whichever impleentation the linker chooses, which isn't necessarily
> the one you wanted.
Thank you for pointing me on that. I will prepare the v2.