Add a function that returns true if any ram_list block represents
volatile memory.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
include/exec/memory.h | 8 ++++++++
softmmu/memory.c | 30 ++++++++++++++++++++++++++++++
2 files changed, 38 insertions(+)
diff --git a/include/exec/memory.h b/include/exec/memory.h
index b116f7c..7ad63f8 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -2649,6 +2649,14 @@ bool ram_block_discard_is_disabled(void);
*/
bool ram_block_discard_is_required(void);
+/**
+ * qemu_ram_volatile: return true if any memory regions are writable and not
+ * backed by shared memory.
+ *
+ * @errp: returned error message identifying the bad region.
+ */
+bool qemu_ram_volatile(Error **errp);
Usually, bool-value functions with an error return true on success. If it deviates from the recommendation, it should at least be documented.
Also, we have a preference for using _is_ in the function name for such tests.
+
#endif
#endif
diff --git a/softmmu/memory.c b/softmmu/memory.c
index f016151..e9536bc 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -2714,6 +2714,36 @@ void memory_global_dirty_log_stop(void)
memory_global_dirty_log_do_stop();
}
+/*
+ * Return true if any memory regions are writable and not backed by shared
+ * memory.
+ */
Let's not duplicate API comments.
+bool qemu_ram_volatile(Error **errp)
+{
+ RAMBlock *block;
+ MemoryRegion *mr;
+ bool ret = false;
+
+ rcu_read_lock();
RCU_READ_LOCK_GUARD()
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
RAMBLOCK_FOREACH() should do.
Or rather use the qemu_ram_foreach_block() helper.
+ mr = block->mr;
+ if (mr &&
+ memory_region_is_ram(mr) &&
+ !memory_region_is_ram_device(mr) &&
+ !memory_region_is_rom(mr) &&
+ (block->fd == -1 || !qemu_ram_is_shared(block))) {
+
+ error_setg(errp, "Memory region %s is volatile",
+ memory_region_name(mr));
+ ret = true;
+ break;
+ }
+ }
+
+ rcu_read_unlock();
+ return ret;
+}
+
static void listener_add_address_space(MemoryListener *listener,
AddressSpace *as)
{
--
1.8.3.1