[PATCH v3 3/8] Add address space API

[Rowan Hart <rowanbhart@gmail.com>]

From: novafacing <rowanbhart@gmail.com>

Signed-off-by: novafacing <rowanbhart@gmail.com>
Signed-off-by: Rowan Hart <rowanbhart@gmail.com>
---
 include/qemu/plugin.h      |  6 +++
 include/qemu/qemu-plugin.h | 45 ++++++++++++++++++++++
 plugins/api.c              | 79 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 130 insertions(+)

diff --git a/include/qemu/plugin.h b/include/qemu/plugin.h
index 9726a9ebf3..38439a37fa 100644
--- a/include/qemu/plugin.h
+++ b/include/qemu/plugin.h
@@ -139,6 +139,12 @@ struct qemu_plugin_tb {
     GArray *cbs;
 };
 
+/* Internal context for address space information */
+struct qemu_plugin_address_space_info {
+    CPUState *cpu;
+    GPtrArray *names;
+};
+
 /**
  * struct CPUPluginState - per-CPU state for plugins
  * @event_mask: plugin event bitmap. Modified only via async work.
diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index 68c8632fd7..1380f7d441 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -926,6 +926,51 @@ QEMU_PLUGIN_API
 int qemu_plugin_write_register(struct qemu_plugin_register *handle,
                               GByteArray *buf);
 
+/** struct qemu_plugin_address_space_info - Opaque handle for space info */
+struct qemu_plugin_address_space_info;
+
+/**
+ * qemu_plugin_get_current_vcpu_address_spaces() - get a list of address spaces
+ * for the current vCPU
+ *
+ * This function should be called in vCPU context, i.e. from a vCPU, translation
+ * block, or operation callback.
+ *
+ * This function is only valid for softmmu targets.
+ *
+ * Returns an opaque qemu_plugin_address_space* handle that is only valid for
+ * the duration of the callback. The caller is not responsible for freeing the
+ * result.
+ */
+QEMU_PLUGIN_API
+struct qemu_plugin_address_space_info*
+qemu_plugin_get_current_vcpu_address_spaces(void);
+
+/**
+ * qemu_plugin_n_address_spaces() - get the number of address spaces
+ *
+ * @info: opaque handle to address space information
+ *
+ * Returns the number of address spaces, or -1 if the handle is invalid.
+ */
+QEMU_PLUGIN_API
+int qemu_plugin_n_address_spaces(struct qemu_plugin_address_space_info *info);
+
+/**
+ * qemu_plugin_address_space_name() - get the name of an address space
+ *
+ * @info: opaque handle to address space information
+ * @idx: index of the address space
+ *
+ * Returns the name of the address space, or NULL if the handle is invalid. The
+ * caller is responsible for freeing the result.
+ *
+ */
+QEMU_PLUGIN_API
+const char*
+qemu_plugin_address_space_name(struct qemu_plugin_address_space_info *info,
+                               unsigned int idx);
+
 /**
  * qemu_plugin_read_memory_vaddr() - read from memory using a virtual address
  *
diff --git a/plugins/api.c b/plugins/api.c
index 79b2dc20b8..d1cc6ff86e 100644
--- a/plugins/api.c
+++ b/plugins/api.c
@@ -39,6 +39,7 @@
 #include "qemu/main-loop.h"
 #include "qemu/plugin.h"
 #include "qemu/log.h"
+#include "system/memory.h"
 #include "tcg/tcg.h"
 #include "exec/gdbstub.h"
 #include "exec/target_page.h"
@@ -452,6 +453,84 @@ int qemu_plugin_write_register(struct qemu_plugin_register *reg,
     return gdb_write_register(current_cpu, buf->data, GPOINTER_TO_INT(reg) - 1);
 }
 
+#ifdef CONFIG_SOFTMMU
+static __thread struct qemu_plugin_address_space_info address_space_info = {
+    NULL, NULL
+};
+static void free_g_string_and_data(gpointer data)
+{
+    g_string_free(data, true);
+}
+#endif
+
+struct qemu_plugin_address_space_info*
+qemu_plugin_get_current_vcpu_address_spaces(void)
+{
+#ifdef CONFIG_SOFTMMU
+    CPUState *cpu = current_cpu;
+
+    if (address_space_info.names == NULL) {
+        address_space_info.cpu = NULL;
+        address_space_info.names = g_ptr_array_new();
+        g_ptr_array_set_free_func(address_space_info.names,
+                                  free_g_string_and_data);
+    }
+
+    g_ptr_array_set_size(address_space_info.names, 0);
+
+    for (size_t i = 0; i < cpu->cpu_ases_count; i++) {
+        AddressSpace *as = cpu_get_address_space(cpu, i);
+
+        if (as == NULL || as->name == NULL) {
+            return NULL;
+        }
+
+        g_ptr_array_add(address_space_info.names,
+                        g_string_new(as->name));
+    }
+
+    address_space_info.cpu = cpu;
+
+    return &address_space_info;
+#else
+    return NULL;
+#endif
+}
+
+int qemu_plugin_n_address_spaces(struct qemu_plugin_address_space_info *info)
+{
+#ifdef CONFIG_SOFTMMU
+    if (info->cpu != current_cpu) {
+        address_space_info.cpu = NULL;
+        g_ptr_array_set_size(address_space_info.names, 0);
+        return -1;
+    }
+
+    return info->names->len;
+#else
+    return -1;
+#endif
+}
+
+const char *
+qemu_plugin_address_space_name(struct qemu_plugin_address_space_info *info,
+                               unsigned int idx)
+{
+#ifdef CONFIG_SOFTMMU
+    if (info->cpu != current_cpu) {
+        address_space_info.cpu = NULL;
+        g_ptr_array_set_size(address_space_info.names, 0);
+        return NULL;
+    }
+
+    if (idx < info->names->len) {
+        GString *name = g_ptr_array_index(info->names, idx);
+        return g_strdup(name->str);
+    }
+#endif
+    return NULL;
+}
+
 bool qemu_plugin_read_memory_vaddr(uint64_t addr, GByteArray *data, size_t len)
 {
     g_assert(current_cpu);
-- 
2.49.0