[patch 09/83] sparc64: Fix PCI resource mapping on sparc64

[Greg KH]

2.6.27-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Max Dmitrichenko <dmitrmax@xxxxxxxxx>

[ Upstream commit 145e1c0023585e0e8f6df22316308ec61c5066b2 ]

There is a problem discovered in recent versions of ATI Mach64 driver
in X.org on sparc64 architecture. In short, the driver fails to mmap
MMIO aperture (PCI resource #2).

I've found that kernel's __pci_mmap_make_offset() returns EINVAL. It
checks whether user attempts to mmap more than the resource length,
which is 0x1000 bytes in our case. But PAGE_SIZE on SPARC64 is 0x2000
and this is what actually is being mmaped. So __pci_mmap_make_offset()
failed for this PCI resource.

Signed-off-by: Max Dmitrichenko <dmitrmax@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 arch/sparc64/kernel/pci.c |   10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

--- a/arch/sparc64/kernel/pci.c
+++ b/arch/sparc64/kernel/pci.c
@@ -1017,6 +1017,7 @@ static int __pci_mmap_make_offset(struct
 
 	for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
 		struct resource *rp = &pdev->resource[i];
+		resource_size_t aligned_end;
 
 		/* Active? */
 		if (!rp->flags)
@@ -1034,8 +1035,15 @@ static int __pci_mmap_make_offset(struct
 				continue;
 		}
 
+		/* Align the resource end to the next page address.
+		 * PAGE_SIZE intentionally added instead of (PAGE_SIZE - 1),
+		 * because actually we need the address of the next byte
+		 * after rp->end.
+		 */
+		aligned_end = (rp->end + PAGE_SIZE) & PAGE_MASK;
+
 		if ((rp->start <= user_paddr) &&
-		    (user_paddr + user_size) <= (rp->end + 1UL))
+		    (user_paddr + user_size) <= aligned_end)
 			break;
 	}
 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/