[IA64, X86_64] fix swiotlb sizing

   Fix swiotlb sizing to match what the comments and the kernel
parameters documentation indicate.  Given a default 16k page size kernel
(ia64) and a 2k swiotlb page size, we're off by a multiple of 8 trying
to size the swiotlb.  When specified on the boot line, the swiotlb is
made 8x bigger than requested.  When left to the default value, it's 8x
smaller than the comments indicate.  For x86_64 the multiplier would be
2x.  The patch below fixes this.  Now, what's a good default swiotlb
size?  Apparently we don't really need 64MB.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

diff --git a/arch/ia64/lib/swiotlb.c b/arch/ia64/lib/swiotlb.c
index ab7b3ad99a7fa9f9c87c78474ee7fda27d3f01b0..dbc0b3e449c5fe7ad8e81c284d00c85b0bf600fe 100644 (file)
--- a/arch/ia64/lib/swiotlb.c
+++ b/arch/ia64/lib/swiotlb.c
@@ -93,8 +93,7 @@ static int __init
 setup_io_tlb_npages(char *str)
 {
        if (isdigit(*str)) {
-               io_tlb_nslabs = simple_strtoul(str, &str, 0) <<
-                       (PAGE_SHIFT - IO_TLB_SHIFT);
+               io_tlb_nslabs = simple_strtoul(str, &str, 0);
                /* avoid tail segment of size < IO_TLB_SEGSIZE */
                io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
        }
@@ -117,7 +116,7 @@ swiotlb_init_with_default_size (size_t default_size)
        unsigned long i;
 
        if (!io_tlb_nslabs) {
-               io_tlb_nslabs = (default_size >> PAGE_SHIFT);
+               io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
                io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
        }