dma.c merged from xen-unstable 17318:b5fea3aeb04b

changesets included:

    changeset:   14912:c1d3f4fbfacf7ea8eab9549823787f13efa2d976
    user:        Christian Limpach <Christian.Limpach@xensource.com>
    date:        Tue Apr 24 17:02:10 2007 +0100
    files:       tools/ioemu/hw/dma.c
    description:
    [qemu-dm] Check for null pointer in dma handler function pointer.

    Signed-off-by: Christian Limpach <Christian.Limpach@xensource.com>
    changeset:   16936:3daab9b636c121bc9d957568ea135b2f40776ca5
    user:        Keir Fraser <keir.fraser@citrix.com>
    date:        Wed Jan 30 09:33:26 2008 +0000
    files:       tools/ioemu/hw/dma.c tools/ioemu/hw/sb16.c
    description:
    ioemu: Better fix for SB16 infinite looping.

    Qemu upstream solves "Fix an infinite loop in the emulated SB16
    device" issue differently as stated in [2]

    [1] http://xenbits.xensource.com/xen-3.1-testing.hg?rev/4b22d472bda6
    [2] http://lists.gnu.org/archive/html/qemu-devel/2008-01/msg00709.html

    Signed-off-by: S. Caglar Onur <caglar@pardus.org.tr>

diff --git a/hw/dma.c b/hw/dma.c
index f192c63d1e9df981d9d53eeab56ee821395e35ee..433ac3d9df2023a2b8a799864846a1fb3701bf07 100644 (file)
--- a/hw/dma.c
+++ b/hw/dma.c
@@ -341,6 +341,8 @@ static void channel_run (int ncont, int ichan)
 #endif
 
     r = dma_controllers[ncont].regs + ichan;
+    if (r->transfer_handler == NULL)
+       return;
     n = r->transfer_handler (r->opaque, ichan + (ncont << 2),
                              r->now[COUNT], (r->base[COUNT] + 1) << ncont);
     r->now[COUNT] = n;
@@ -446,6 +448,13 @@ static int dma_phony_handler (void *opaque, int nchan, int dma_pos, int dma_len)
     return dma_pos;
 }
 
+static int dma_phony_handler (void *opaque, int nchan, int dma_pos, int dma_len)
+{
+    dolog ("unregistered DMA channel used nchan=%d dma_pos=%d dma_len=%d\n",
+           nchan, dma_pos, dma_len);
+    return dma_pos;
+}
+
 /* dshift = 0: 8 bit DMA, 1 = 16 bit DMA */
 static void dma_init2(struct dma_cont *d, int base, int dshift,
                       int page_base, int pageh_base)