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 <address@hidden>
---
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;
+ /* Internal implementation constraints: */
+ struct {
+ /* If nonzero, specifies the minimum size implemented. Smaller sizes
+ * will be rounded upwards and a partial result will be returned.
+ */
+ unsigned min_access_size;
+ /* If nonzero, specifies the maximum size implemented. Larger sizes
+ * will be done as a series of accesses with smaller sizes.
+ */
+ unsigned max_access_size;
+ /* If true, unaligned accesses are supported. Otherwise all accesses
+ * are converted to (possibly multiple) naturally aligned accesses.
+ */
+ bool unaligned;
+ } impl;
+};
+
+typedef struct CoalescedMemoryRange CoalescedMemoryRange;
+
+struct CoalescedMemoryRange {
+ target_phys_addr_t start;
+ target_phys_addr_t size;
+ QTAILQ_ENTRY(coalesced_ranges) link;
+};
+
+struct MemoryRegion {
+ /* All fields are private - violators will be prosecuted */
+ const MemoryRegionOps *ops;
+ MemoryRegion *parent;
+ target_phys_addr_t size;
+ target_phys_addr_t addr;
+ ram_addr_t ram_addr;
+ unsigned priority;
+ bool may_overlap;
+ QTAILQ_HEAD(subregions, MemoryRegion) subregions;
+ QTAILQ_ENTRY(subregions) subregions_link;
+ QTAILQ_HEAD(coalesced_ranges, CoalescedMemoryRange) coalesced;
+};
+
+/* Initialize a memory region
+ *
+ * The region typically acts as a container for other memory regions.
+ */
+void memory_region_init(MemoryRegion *mr,
+ target_phys_addr_t size);
+/* Initialize an I/O memory region. Accesses into the region will be
+ * cause the callbacks in @ops to be called.
+ *
+ * if @size is nonzero, subregions will be clipped to @size.
+ */
+void memory_region_init_io(MemoryRegion *mr,
+ const MemoryRegionOps *ops,
+ target_phys_addr_t size);
+/* Initialize an I/O memory region. Accesses into the region will be
+ * modify memory directly.
+ */
+void memory_region_init_ram(MemoryRegion *mr,
+ target_phys_addr_t size);
+/* Initialize a RAM memory region. Accesses into the region will be
+ * modify memory in @ptr directly.
+ */
+void memory_region_init_ram_ptr(MemoryRegion *mr,
+ target_phys_addr_t size,
+ void *ptr);
+/* Destroy a memory region. The memory becomes inaccessible. */
+void memory_region_destroy(MemoryRegion *mr);
+/* Sets an offset to be added to MemoryRegionOps callbacks. */
+void memory_region_set_offset(MemoryRegion *mr, target_phys_addr_t
offset);
+/* Turn loggging on or off for specified client (display, migration) */
+void memory_region_set_log(MemoryRegion *mr, bool log, unsigned client);
+/* Enable memory coalescing for the region. MMIO ->write callbacks may be
+ * delayed until a non-coalesced MMIO is issued.
+ */
+void memory_region_set_coalescing(MemoryRegion *mr);
+/* Enable memory coalescing for a sub-range of the region. MMIO ->write
+ * callbacks may be delayed until a non-coalesced MMIO is issued.
+ */
+void memory_region_add_coalescing(MemoryRegion *mr,
+ target_phys_addr_t offset,
+ target_phys_addr_t size);
+/* Disable MMIO coalescing for the region. */
+void memory_region_clear_coalescing(MemoryRegion *mr);
+
+/* Add a sub-region at @offset. The sub-region may not overlap with other
+ * subregions (except for those explicitly marked as overlapping)
+ */
+void memory_region_add_subregion(MemoryRegion *mr,
+ target_phys_addr_t offset,
+ MemoryRegion *subregion);
+/* Add a sub-region at @offset. The sun-region may overlap other
subregions;
+ * conflicts are resolved by having a higher @priority hide a lower
@priority.
+ * Subregions without priority are taken as @priority 0.
+ */
+void memory_region_add_subregion_overlap(MemoryRegion *mr,
+ target_phys_addr_t offset,
+ MemoryRegion *subregion,
+ unsigned priority);
+/* Remove a subregion. */
+void memory_region_del_subregion(MemoryRegion *mr,
+ MemoryRegion *subregion);
+
+#endif