Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[sfrench/cifs-2.6.git] / lib / pci_iomap.c

diff --git a/lib/pci_iomap.c b/lib/pci_iomap.c
index 0d83ea8a9605429aa5e79262bef539e51bfec456..bcce5f149310136a6eaed0c3830c996ac8484008 100644 (file)
--- 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 */