PCI: Fix pci_mmap_fits() for HAVE_PCI_RESOURCE_TO_USER platforms

commit 6bccc7f426abd640f08d8c75fb22f99483f201b4 upstream.

In the PCI_MMAP_PROCFS case when the address being passed by the user is a
'user visible' resource address based on the bus window, and not the actual
contents of the resource, that's what we need to be checking it against.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 82edc0f..ce4cbd1 100644 (file)
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -772,15 +772,19 @@ void pci_remove_legacy_files(struct pci_bus *b)
 int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma,
                  enum pci_mmap_api mmap_api)
 {
 int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma,
                  enum pci_mmap_api mmap_api)
 {

-       unsigned long nr, start, size, pci_start;
+       unsigned long nr, start, size;
+       resource_size_t pci_start = 0, pci_end;

 
        if (pci_resource_len(pdev, resno) == 0)
                return 0;
        nr = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
        start = vma->vm_pgoff;
        size = ((pci_resource_len(pdev, resno) - 1) >> PAGE_SHIFT) + 1;
 
        if (pci_resource_len(pdev, resno) == 0)
                return 0;
        nr = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
        start = vma->vm_pgoff;
        size = ((pci_resource_len(pdev, resno) - 1) >> PAGE_SHIFT) + 1;

-       pci_start = (mmap_api == PCI_MMAP_PROCFS) ?
-                       pci_resource_start(pdev, resno) >> PAGE_SHIFT : 0;
+       if (mmap_api == PCI_MMAP_PROCFS) {
+               pci_resource_to_user(pdev, resno, &pdev->resource[resno],
+                                    &pci_start, &pci_end);
+               pci_start >>= PAGE_SHIFT;
+       }

        if (start >= pci_start && start < pci_start + size &&
                        start + nr <= pci_start + size)
                return 1;
        if (start >= pci_start && start < pci_start + size &&
                        start + nr <= pci_start + size)
                return 1;