This value can be accessed only during a memory callback, using
new qemu_plugin_mem_get_value function.
Returned value can be extended when QEMU will support accesses wider
than 128 bits.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1719
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2152
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Xingtao Yao <yaoxt.fnst@fujitsu.com>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
---
include/qemu/qemu-plugin.h | 32 ++++++++++++++++++++++++++++++++
plugins/api.c | 33 +++++++++++++++++++++++++++++++++
plugins/qemu-plugins.symbols | 1 +
3 files changed, 66 insertions(+)
diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index c71c705b699..649ce89815f 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -262,6 +262,29 @@ enum qemu_plugin_mem_rw {
QEMU_PLUGIN_MEM_RW,
};
+enum qemu_plugin_mem_value_type {
+ QEMU_PLUGIN_MEM_VALUE_U8,
+ QEMU_PLUGIN_MEM_VALUE_U16,
+ QEMU_PLUGIN_MEM_VALUE_U32,
+ QEMU_PLUGIN_MEM_VALUE_U64,
+ QEMU_PLUGIN_MEM_VALUE_U128,
+};
+
+/* typedef qemu_plugin_mem_value - value accessed during a load/store */
+typedef struct {
+ enum qemu_plugin_mem_value_type type;
+ union {
+ uint8_t u8;
+ uint16_t u16;
+ uint32_t u32;
+ uint64_t u64;
+ struct {
+ uint64_t low;
+ uint64_t high;
+ } u128;
+ } data;
+} qemu_plugin_mem_value;
+
/**
* enum qemu_plugin_cond - condition to enable callback
*
@@ -551,6 +574,15 @@ bool qemu_plugin_mem_is_big_endian(qemu_plugin_meminfo_t info);
QEMU_PLUGIN_API
bool qemu_plugin_mem_is_store(qemu_plugin_meminfo_t info);
+/**
+ * qemu_plugin_mem_get_mem_value() - return last value loaded/stored
+ * @info: opaque memory transaction handle
+ *
+ * Returns: memory value
+ */
+QEMU_PLUGIN_API
+qemu_plugin_mem_value qemu_plugin_mem_get_value(qemu_plugin_meminfo_t info);
+
/**
* qemu_plugin_get_hwaddr() - return handle for memory operation
* @info: opaque memory info structure
diff --git a/plugins/api.c b/plugins/api.c
index 2ff13d09de6..3316d4a04d4 100644
--- a/plugins/api.c
+++ b/plugins/api.c
@@ -351,6 +351,39 @@ bool qemu_plugin_mem_is_store(qemu_plugin_meminfo_t info)
return get_plugin_meminfo_rw(info) & QEMU_PLUGIN_MEM_W;
}
+qemu_plugin_mem_value qemu_plugin_mem_get_value(qemu_plugin_meminfo_t info)
+{
+ uint64_t low = current_cpu->neg.plugin_mem_value_low;
+ qemu_plugin_mem_value value;
+
+ switch (qemu_plugin_mem_size_shift(info)) {
+ case 0:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U8;
+ value.data.u8 = (uint8_t)low;
+ break;
+ case 1:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U16;
+ value.data.u16 = (uint16_t)low;
+ break;
+ case 2:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U32;
+ value.data.u32 = (uint32_t)low;
+ break;
+ case 3:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U64;
+ value.data.u64 = low;
+ break;
+ case 4:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U128;
+ value.data.u128.low = low;
+ value.data.u128.high = current_cpu->neg.plugin_mem_value_high;
+ break;
+ default:
+ g_assert_not_reached();
+ }
+ return value;
+}
+
/*
* Virtual Memory queries
*/
diff --git a/plugins/qemu-plugins.symbols b/plugins/qemu-plugins.symbols
index ca773d8d9fe..eed9d8abd90 100644
--- a/plugins/qemu-plugins.symbols
+++ b/plugins/qemu-plugins.symbols
@@ -13,6 +13,7 @@
qemu_plugin_insn_size;
qemu_plugin_insn_symbol;
qemu_plugin_insn_vaddr;
+ qemu_plugin_mem_get_value;
qemu_plugin_mem_is_big_endian;
qemu_plugin_mem_is_sign_extended;
qemu_plugin_mem_is_store;
--
2.39.2