On 05/19/2011 09:12 AM, Avi Kivity wrote:
The memory API separates the attributes of a memory region (its size, how
reads or writes are handled, dirty logging, and coalescing) from where it
is mapped and whether it is enabled. This allows a device to configure
a memory region once, then hand it off to its parent bus to map it according
to the bus configuration.
Hierarchical registration also allows a device to compose a region out of
a number of sub-regions with different properties; for example some may be
RAM while others may be MMIO.
Signed-off-by: Avi Kivity<avi@xxxxxxxxxx>
---
memory.h | 142 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 142 insertions(+), 0 deletions(-)
create mode 100644 memory.h
diff --git a/memory.h b/memory.h
new file mode 100644
index 0000000..77c5951
--- /dev/null
+++ b/memory.h
@@ -0,0 +1,142 @@
+#ifndef MEMORY_H
+#define MEMORY_H
+
+#include<stdint.h>
+#include<stdbool.h>
+#include "qemu-common.h"
+#include "cpu-common.h"
+#include "targphys.h"
+#include "qemu-queue.h"
+
+typedef struct MemoryRegionOps MemoryRegionOps;
+typedef struct MemoryRegion MemoryRegion;
+
+/*
+ * Memory region callbacks
+ */
+struct MemoryRegionOps {
+ /* Read from the memory region. @addr is relative to @mr; @size is
+ * in bytes. */
+ uint64_t (*read)(MemoryRegion *mr,
+ target_phys_addr_t addr,
+ unsigned size);
+ /* Write to the memory region. @addr is relative to @mr; @size is
+ * in bytes. */
+ void (*write)(MemoryRegion *mr,
+ target_phys_addr_t addr,
+ uint64_t data,
+ unsigned size);
+ /* Guest-visible constraints: */
+ struct {
+ /* If nonzero, specify bounds on access sizes beyond which a machine
+ * check is thrown.
+ */
+ unsigned min_access_size;
+ unsigned max_access_size;
+ /* If true, unaligned accesses are supported. Otherwise unaligned
+ * accesses throw machine checks.
+ */
+ bool unaligned;
+ } valid;
Under what circumstances would this be used?
The behavior of devices that receive non-natural accesses varies wildly.
For PCI devices, invalid accesses almost always return ~0. I can't
think of a device where an MCE would occur.
Regards,
Anthony Liguori
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
