Merge tag 'for-hubcap-v4.9-readahead' of git://github.com/martinbrandenburg/linux

orangefs: integrate readahead cache changes from out-of-tree

The readahead cache has long been present as a compile time option to
OrangeFS. As it had not been tested in some time, it was disabled by
default. Recently, Walt Ligon started work reviving it, which eventually
culminated in the commit below to OrangeFS SVN.

r12519 | walt | 2016-07-13 14:32:42 -0400 (Wed, 13 Jul 2016) | 1 line
reintegrating readahead cache code

This cache is implemented almost entirely in userspace. There are a few
parameters exposed via sysfs, and the cache must be flushed after an
inode is released.

1 files changed, 15 insertions, 58 deletions

diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
index 14cba600da7a..81556b843a8e 100644
--- a/arch/microblaze/pci/pci-common.c
+++ b/arch/microblaze/pci/pci-common.c
@@ -219,33 +219,6 @@ static struct resource *__pci_mmap_make_offset(struct pci_dev *dev,
 }
 
 /*
- * Set vm_page_prot of VMA, as appropriate for this architecture, for a pci
- * device mapping.
- */
-static pgprot_t __pci_mmap_set_pgprot(struct pci_dev *dev, struct resource *rp,
-				      pgprot_t protection,
-				      enum pci_mmap_state mmap_state,
-				      int write_combine)
-{
-	pgprot_t prot = protection;
-
-	/* Write combine is always 0 on non-memory space mappings. On
-	 * memory space, if the user didn't pass 1, we check for a
-	 * "prefetchable" resource. This is a bit hackish, but we use
-	 * this to workaround the inability of /sysfs to provide a write
-	 * combine bit
-	 */
-	if (mmap_state != pci_mmap_mem)
-		write_combine = 0;
-	else if (write_combine == 0) {
-		if (rp->flags & IORESOURCE_PREFETCH)
-			write_combine = 1;
-	}
-
-	return pgprot_noncached(prot);
-}
-
-/*
  * This one is used by /dev/mem and fbdev who have no clue about the
  * PCI device, it tries to find the PCI device first and calls the
  * above routine
@@ -317,9 +290,7 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 		return -EINVAL;
 
 	vma->vm_pgoff = offset >> PAGE_SHIFT;
-	vma->vm_page_prot = __pci_mmap_set_pgprot(dev, rp,
-						  vma->vm_page_prot,
-						  mmap_state, write_combine);
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
 	ret = remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
 			       vma->vm_end - vma->vm_start, vma->vm_page_prot);
@@ -473,39 +444,25 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar,
 			  const struct resource *rsrc,
 			  resource_size_t *start, resource_size_t *end)
 {
-	struct pci_controller *hose = pci_bus_to_host(dev->bus);
-	resource_size_t offset = 0;
+	struct pci_bus_region region;
 
-	if (hose == NULL)
+	if (rsrc->flags & IORESOURCE_IO) {
+		pcibios_resource_to_bus(dev->bus, &region,
+					(struct resource *) rsrc);
+		*start = region.start;
+		*end = region.end;
 		return;
+	}
 
-	if (rsrc->flags & IORESOURCE_IO)
-		offset = (unsigned long)hose->io_base_virt - _IO_BASE;
-
-	/* We pass a fully fixed up address to userland for MMIO instead of
-	 * a BAR value because X is lame and expects to be able to use that
-	 * to pass to /dev/mem !
+	/* We pass a CPU physical address to userland for MMIO instead of a
+	 * BAR value because X is lame and expects to be able to use that
+	 * to pass to /dev/mem!
 	 *
-	 * That means that we'll have potentially 64 bits values where some
-	 * userland apps only expect 32 (like X itself since it thinks only
-	 * Sparc has 64 bits MMIO) but if we don't do that, we break it on
-	 * 32 bits CHRPs :-(
-	 *
-	 * Hopefully, the sysfs insterface is immune to that gunk. Once X
-	 * has been fixed (and the fix spread enough), we can re-enable the
-	 * 2 lines below and pass down a BAR value to userland. In that case
-	 * we'll also have to re-enable the matching code in
-	 * __pci_mmap_make_offset().
-	 *
-	 * BenH.
+	 * That means we may have 64-bit values where some apps only expect
+	 * 32 (like X itself since it thinks only Sparc has 64-bit MMIO).
 	 */
-#if 0
-	else if (rsrc->flags & IORESOURCE_MEM)
-		offset = hose->pci_mem_offset;
-#endif
-
-	*start = rsrc->start - offset;
-	*end = rsrc->end - offset;
+	*start = rsrc->start;
+	*end = rsrc->end;
 }
 
 /**