| Message ID | 1421256142-11512-10-git-send-email-mst@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Wed, Jan 14, 2015 at 07:27:54PM +0200, Michael S. Tsirkin wrote: > Virtio drivers should map the part of the BAR they need, not necessarily > all of it. > > Cc: Bjorn Helgaas <bhelgaas@google.com> > Cc: linux-pci@vger.kernel.org > Acked-by: Arnd Bergmann <arnd@arndb.de> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Sorry it took so long for me to notice these! > --- > > Bjorn, can you please ack this for merging through the virtio tree? > > include/asm-generic/pci_iomap.h | 10 ++++++++++ > lib/pci_iomap.c | 35 ++++++++++++++++++++++++++++++----- > 2 files changed, 40 insertions(+), 5 deletions(-) > > diff --git a/include/asm-generic/pci_iomap.h b/include/asm-generic/pci_iomap.h > index ce37349..7389c87 100644 > --- a/include/asm-generic/pci_iomap.h > +++ b/include/asm-generic/pci_iomap.h > @@ -15,6 +15,9 @@ struct pci_dev; > #ifdef CONFIG_PCI > /* Create a virtual mapping cookie for a PCI BAR (memory or IO) */ > extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max); > +extern void __iomem *pci_iomap_range(struct pci_dev *dev, int bar, > + unsigned long offset, > + unsigned long maxlen); > /* Create a virtual mapping cookie for a port on a given PCI device. > * Do not call this directly, it exists to make it easier for architectures > * to override */ > @@ -30,6 +33,13 @@ static inline void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned lon > { > return NULL; > } > + > +static inline void __iomem *pci_iomap_range(struct pci_dev *dev, int bar, > + unsigned long offset, > + unsigned long maxlen) > +{ > + return NULL; > +} > #endif > > #endif /* __ASM_GENERIC_IO_H */ > diff --git a/lib/pci_iomap.c b/lib/pci_iomap.c > index 0d83ea8..bcce5f1 100644 > --- a/lib/pci_iomap.c > +++ b/lib/pci_iomap.c > @@ -10,10 +10,11 @@ > > #ifdef CONFIG_PCI > /** > - * pci_iomap - create a virtual mapping cookie for a PCI BAR > + * pci_iomap_range - create a virtual mapping cookie for a PCI BAR > * @dev: PCI device that owns the BAR > * @bar: BAR number > - * @maxlen: length of the memory to map > + * @offset: map memory at the given offset in BAR > + * @maxlen: max length of the memory to map > * > * Using this function you will get a __iomem address to your device BAR. > * You can access it using ioread*() and iowrite*(). These functions hide > @@ -21,16 +22,21 @@ > * you expect from them in the correct way. > * > * @maxlen specifies the maximum length to map. If you want to get access to > - * the complete BAR without checking for its length first, pass %0 here. > + * the complete BAR from offset to the end, pass %0 here. > * */ > -void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) > +void __iomem *pci_iomap_range(struct pci_dev *dev, > + int bar, > + unsigned long offset, > + unsigned long maxlen) > { > resource_size_t start = pci_resource_start(dev, bar); > resource_size_t len = pci_resource_len(dev, bar); > unsigned long flags = pci_resource_flags(dev, bar); > > - if (!len || !start) > + if (len <= offset || !start) > return NULL; > + len -= offset; > + start += offset; > if (maxlen && len > maxlen) > len = maxlen; > if (flags & IORESOURCE_IO) > @@ -43,6 +49,25 @@ void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) > /* What? */ > return NULL; > } > +EXPORT_SYMBOL(pci_iomap_range); > > +/** > + * pci_iomap - create a virtual mapping cookie for a PCI BAR > + * @dev: PCI device that owns the BAR > + * @bar: BAR number > + * @maxlen: length of the memory to map > + * > + * Using this function you will get a __iomem address to your device BAR. > + * You can access it using ioread*() and iowrite*(). These functions hide > + * the details if this is a MMIO or PIO address space and will just do what > + * you expect from them in the correct way. > + * > + * @maxlen specifies the maximum length to map. If you want to get access to > + * the complete BAR without checking for its length first, pass %0 here. > + * */ > +void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) > +{ > + return pci_iomap_range(dev, bar, 0, maxlen); > +} > EXPORT_SYMBOL(pci_iomap); > #endif /* CONFIG_PCI */ > -- > MST > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/asm-generic/pci_iomap.h b/include/asm-generic/pci_iomap.h index ce37349..7389c87 100644 --- a/include/asm-generic/pci_iomap.h +++ b/include/asm-generic/pci_iomap.h @@ -15,6 +15,9 @@ struct pci_dev; #ifdef CONFIG_PCI /* Create a virtual mapping cookie for a PCI BAR (memory or IO) */ extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max); +extern void __iomem *pci_iomap_range(struct pci_dev *dev, int bar, + unsigned long offset, + unsigned long maxlen); /* Create a virtual mapping cookie for a port on a given PCI device. * Do not call this directly, it exists to make it easier for architectures * to override */ @@ -30,6 +33,13 @@ static inline void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned lon { return NULL; } + +static inline void __iomem *pci_iomap_range(struct pci_dev *dev, int bar, + unsigned long offset, + unsigned long maxlen) +{ + return NULL; +} #endif #endif /* __ASM_GENERIC_IO_H */ diff --git a/lib/pci_iomap.c b/lib/pci_iomap.c index 0d83ea8..bcce5f1 100644 --- a/lib/pci_iomap.c +++ b/lib/pci_iomap.c @@ -10,10 +10,11 @@ #ifdef CONFIG_PCI /** - * pci_iomap - create a virtual mapping cookie for a PCI BAR + * pci_iomap_range - create a virtual mapping cookie for a PCI BAR * @dev: PCI device that owns the BAR * @bar: BAR number - * @maxlen: length of the memory to map + * @offset: map memory at the given offset in BAR + * @maxlen: max length of the memory to map * * Using this function you will get a __iomem address to your device BAR. * You can access it using ioread*() and iowrite*(). These functions hide @@ -21,16 +22,21 @@ * you expect from them in the correct way. * * @maxlen specifies the maximum length to map. If you want to get access to - * the complete BAR without checking for its length first, pass %0 here. + * the complete BAR from offset to the end, pass %0 here. * */ -void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) +void __iomem *pci_iomap_range(struct pci_dev *dev, + int bar, + unsigned long offset, + unsigned long maxlen) { resource_size_t start = pci_resource_start(dev, bar); resource_size_t len = pci_resource_len(dev, bar); unsigned long flags = pci_resource_flags(dev, bar); - if (!len || !start) + if (len <= offset || !start) return NULL; + len -= offset; + start += offset; if (maxlen && len > maxlen) len = maxlen; if (flags & IORESOURCE_IO) @@ -43,6 +49,25 @@ void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) /* What? */ return NULL; } +EXPORT_SYMBOL(pci_iomap_range); +/** + * pci_iomap - create a virtual mapping cookie for a PCI BAR + * @dev: PCI device that owns the BAR + * @bar: BAR number + * @maxlen: length of the memory to map + * + * Using this function you will get a __iomem address to your device BAR. + * You can access it using ioread*() and iowrite*(). These functions hide + * the details if this is a MMIO or PIO address space and will just do what + * you expect from them in the correct way. + * + * @maxlen specifies the maximum length to map. If you want to get access to + * the complete BAR without checking for its length first, pass %0 here. + * */ +void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) +{ + return pci_iomap_range(dev, bar, 0, maxlen); +} EXPORT_SYMBOL(pci_iomap); #endif /* CONFIG_PCI */