[Qemu-devel] [PATCH] dma: Define dma_context_memory and use in sysbus-ohci

[Peter Maydell]

Define a new global dma_context_memory which is a DMAContext corresponding
to the global address_space_memory AddressSpace. This can be used by
sysbus peripherals like sysbus-ohci which need to do DMA.

In particular, use it in the sysbus-ohci device, which fixes a
segfault when attempting to use that device.

Signed-off-by: Peter Maydell <address@hidden>
---
As suggested by Avi. I could have split this patch into one defining
the new global and one actually using it, but since the hcd-ohci
change would be a one-liner it didn't seem worthwhile.

 dma.h             |    5 +++++
 exec.c            |    5 +++++
 hw/usb/hcd-ohci.c |    2 +-
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/dma.h b/dma.h
index 1bd6f4a..f7cf5e7 100644
--- a/dma.h
+++ b/dma.h
@@ -68,6 +68,11 @@ struct DMAContext {
     DMAUnmapFunc *unmap;
 };
 
+/* A global DMA context corresponding to the address_space_memory
+ * AddressSpace, for sysbus devices which do DMA.
+ */
+extern DMAContext dma_context_memory;
+
 static inline void dma_barrier(DMAContext *dma, DMADirection dir)
 {
     /*
diff --git a/exec.c b/exec.c
index 750008c..a59ed31 100644
--- a/exec.c
+++ b/exec.c
@@ -34,6 +34,7 @@
 #include "hw/xen.h"
 #include "qemu-timer.h"
 #include "memory.h"
+#include "dma.h"
 #include "exec-memory.h"
 #if defined(CONFIG_USER_ONLY)
 #include <qemu.h>
@@ -103,6 +104,7 @@ static MemoryRegion *system_io;
 
 AddressSpace address_space_io;
 AddressSpace address_space_memory;
+DMAContext dma_context_memory;
 
 MemoryRegion io_mem_ram, io_mem_rom, io_mem_unassigned, io_mem_notdirty;
 static MemoryRegion io_mem_subpage_ram;
@@ -3276,6 +3278,9 @@ static void memory_map_init(void)
     memory_listener_register(&core_memory_listener, &address_space_memory);
     memory_listener_register(&io_memory_listener, &address_space_io);
     memory_listener_register(&tcg_memory_listener, &address_space_memory);
+
+    dma_context_init(&dma_context_memory, &address_space_memory,
+                     NULL, NULL, NULL);
 }
 
 MemoryRegion *get_system_memory(void)
diff --git a/hw/usb/hcd-ohci.c b/hw/usb/hcd-ohci.c
index 59c7055..eb1cb70 100644
--- a/hw/usb/hcd-ohci.c
+++ b/hw/usb/hcd-ohci.c
@@ -1846,7 +1846,7 @@ static int ohci_init_pxa(SysBusDevice *dev)
 
     /* Cannot fail as we pass NULL for masterbus */
     usb_ohci_init(&s->ohci, &dev->qdev, s->num_ports, s->dma_offset, NULL, 0,
-                  NULL);
+                  &dma_context_memory);
     sysbus_init_irq(dev, &s->ohci.irq);
     sysbus_init_mmio(dev, &s->ohci.mem);
 
-- 
1.7.9.5