From: Elysia Witham <elysia.wit...@ll.mit.edu>
In order for the QPP API to resolve interactions between plugins,
plugins must export their own names which cannot match any other
loaded plugins.
Signed-off-by: Elysia Witham <elysia.wit...@ll.mit.edu>
Signed-off-by: Andrew Fasano <fas...@mit.edu>
---
include/qemu/qemu-plugin.h | 2 +-
plugins/core.c | 12 +++++++++
plugins/loader.c | 50 +++++++++++++++++++++++++++++++++-----
plugins/plugin.h | 7 ++++++
tests/plugin/bb.c | 1 +
tests/plugin/empty.c | 1 +
tests/plugin/insn.c | 1 +
tests/plugin/mem.c | 1 +
tests/plugin/syscall.c | 1 +
9 files changed, 69 insertions(+), 7 deletions(-)
diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index d0e9d03adf..5326f33ce8 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -51,7 +51,7 @@ typedef uint64_t qemu_plugin_id_t;
extern QEMU_PLUGIN_EXPORT int qemu_plugin_version;
-#define QEMU_PLUGIN_VERSION 1
+#define QEMU_PLUGIN_VERSION 2
/**
* struct qemu_info_t - system information for plugins
diff --git a/plugins/core.c b/plugins/core.c
index ccb770a485..5fbdcb5768 100644
--- a/plugins/core.c
+++ b/plugins/core.c
@@ -236,6 +236,18 @@ void qemu_plugin_vcpu_exit_hook(CPUState *cpu)
qemu_rec_mutex_unlock(&plugin.lock);
}
+int name_to_plugin_version(const char *name)
+{
+ struct qemu_plugin_ctx *ctx;
+ QTAILQ_FOREACH(ctx, &plugin.ctxs, entry) {
+ if (strcmp(ctx->name, name) == 0) {
+ return ctx->version;
+ }
+ }
+ warn_report("Could not find any plugin named %s.", name);
+ return -1;
+}
+
struct plugin_for_each_args {
struct qemu_plugin_ctx *ctx;
qemu_plugin_vcpu_simple_cb_t cb;
diff --git a/plugins/loader.c b/plugins/loader.c
index 88c30bde2d..12c0680e03 100644
--- a/plugins/loader.c
+++ b/plugins/loader.c
@@ -177,7 +177,7 @@ QEMU_DISABLE_CFI
static int plugin_load(struct qemu_plugin_desc *desc, const qemu_info_t *info,
Error **errp)
{
qemu_plugin_install_func_t install;
- struct qemu_plugin_ctx *ctx;
+ struct qemu_plugin_ctx *ctx, *ctx2;
gpointer sym;
int rc;
@@ -208,17 +208,55 @@ static int plugin_load(struct qemu_plugin_desc *desc,
const qemu_info_t *info, E
desc->path, g_module_error());
goto err_symbol;
} else {
- int version = *(int *)sym;
- if (version < QEMU_PLUGIN_MIN_VERSION) {
+ ctx->version = *(int *)sym;
+ if (ctx->version < QEMU_PLUGIN_MIN_VERSION) {
error_setg(errp, "Could not load plugin %s: plugin requires API
version %d, but "
"this QEMU supports only a minimum version of %d",
- desc->path, version, QEMU_PLUGIN_MIN_VERSION);
+ desc->path, ctx->version, QEMU_PLUGIN_MIN_VERSION);
goto err_symbol;
- } else if (version > QEMU_PLUGIN_VERSION) {
+ } else if (ctx->version > QEMU_PLUGIN_VERSION) {
error_setg(errp, "Could not load plugin %s: plugin requires API
version %d, but "
"this QEMU supports only up to version %d",
- desc->path, version, QEMU_PLUGIN_VERSION);
+ desc->path, ctx->version, QEMU_PLUGIN_VERSION);
goto err_symbol;
+ } else if (ctx->version < QPP_MINIMUM_VERSION) {
+ ctx->name = NULL;
+ } else {
+ if (!g_module_symbol(ctx->handle, "qemu_plugin_name", &sym)) {
+ error_setg(errp, "Could not load plugin %s: plugin does not "
+ "declare plugin name %s",
+ desc->path, g_module_error());
+ goto err_symbol;
+ }
+ ctx->name = (const char *)strdup(*(const char **)sym);
+ QTAILQ_FOREACH(ctx2, &plugin.ctxs, entry) {
+ if (strcmp(ctx2->name, ctx->name) == 0) {
+ error_setg(errp, "Could not load plugin %s as the name %s "
+ "is already in use by plugin at %s",
+ desc->path, ctx->name, ctx2->desc->path);
+ goto err_symbol;
+ }
+ }
+ if (g_module_symbol(ctx->handle, "qemu_plugin_uses", &sym)) {
+ const char **dependencies = &(*(const char **)sym);
+ bool found = false;
+ while (*dependencies) {
+ found = false;
+ QTAILQ_FOREACH(ctx2, &plugin.ctxs, entry) {
+ if (strcmp(ctx2->name, *dependencies) == 0) {
+ dependencies++;
+ found = true;
+ break;
+ }
+ }
+ if (!found) {
+ error_setg(errp, "Could not load plugin %s as it is "
+ "dependent on %s which is not loaded",
+ ctx->name, *dependencies);
+ goto err_symbol;
+ }
+ }
+ }
}
}
diff --git a/plugins/plugin.h b/plugins/plugin.h
index 5eb2fdbc85..ce885bfa98 100644
--- a/plugins/plugin.h
+++ b/plugins/plugin.h
@@ -16,6 +16,7 @@
#include "qemu/qht.h"
#define QEMU_PLUGIN_MIN_VERSION 0
+#define QPP_MINIMUM_VERSION 2
/* global state */
struct qemu_plugin_state {
@@ -50,6 +51,8 @@ struct qemu_plugin_state {
struct qemu_plugin_ctx {
GModule *handle;
qemu_plugin_id_t id;
+ const char *name;
+ int version;
struct qemu_plugin_cb *callbacks[QEMU_PLUGIN_EV_MAX];
QTAILQ_ENTRY(qemu_plugin_ctx) entry;
/*
@@ -64,6 +67,8 @@ struct qemu_plugin_ctx {
struct qemu_plugin_ctx *plugin_id_to_ctx_locked(qemu_plugin_id_t id);
+struct qemu_plugin_ctx *plugin_name_to_ctx_locked(const char* name);
+
void plugin_register_inline_op(GArray **arr,
enum qemu_plugin_mem_rw rw,
enum qemu_plugin_op op, void *ptr,
@@ -97,4 +102,6 @@ void plugin_register_vcpu_mem_cb(GArray **arr,
void exec_inline_op(struct qemu_plugin_dyn_cb *cb);
+int name_to_plugin_version(const char *name);
+
#endif /* PLUGIN_H */
diff --git a/tests/plugin/bb.c b/tests/plugin/bb.c
index 7d470a1011..c04e5aaf90 100644
--- a/tests/plugin/bb.c
+++ b/tests/plugin/bb.c
@@ -15,6 +15,7 @@
#include <qemu-plugin.h>
QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
+QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "bb";
typedef struct {
GMutex lock;
diff --git a/tests/plugin/empty.c b/tests/plugin/empty.c
index 8fa6bacd93..0f3d2b92b9 100644
--- a/tests/plugin/empty.c
+++ b/tests/plugin/empty.c
@@ -14,6 +14,7 @@
#include <qemu-plugin.h>
QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
+QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "empty";
/*
* Empty TB translation callback.
diff --git a/tests/plugin/insn.c b/tests/plugin/insn.c
index cd5ea5d4ae..3f71138139 100644
--- a/tests/plugin/insn.c
+++ b/tests/plugin/insn.c
@@ -15,6 +15,7 @@
#include <qemu-plugin.h>
QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
+QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "insn";
#define MAX_CPUS 8 /* lets not go nuts */
diff --git a/tests/plugin/mem.c b/tests/plugin/mem.c
index 4570f7d815..35e5d7fe2a 100644
--- a/tests/plugin/mem.c
+++ b/tests/plugin/mem.c
@@ -15,6 +15,7 @@
#include <qemu-plugin.h>
QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
+QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "mem";
static uint64_t inline_mem_count;
static uint64_t cb_mem_count;
diff --git a/tests/plugin/syscall.c b/tests/plugin/syscall.c
index 96040c578f..922bdbd2e6 100644
--- a/tests/plugin/syscall.c
+++ b/tests/plugin/syscall.c
@@ -15,6 +15,7 @@
#include <qemu-plugin.h>
QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
+QEMU_PLUGIN_EXPORT const char *qemu_plugin_name = "syscall";
typedef struct {
int64_t num;
--
2.34.1
