Added three types of modules:
typedef enum {
MODULE_LOAD_BLOCK = 0,
MODULE_LOAD_UI,
MODULE_LOAD_NET,
MODULE_LOAD_MAX,
} module_load_type;
and their loading function:
void module_load(module_load_type).
which loads all ".so" files in a subdir under configured ${MODDIR}, e.g.
"/usr/lib/qemu/block". Modules of each type should be loaded before
respective subsystem initialization code.
The init function of dynamic module is no longer with
__attribute__((constructor)) and need to be explicitly called once
loaded. The function name is mangled with per configure fingerprint as:
init_$(date +%s$$$RANDOM)
Which is known to module_load function: the loading fails if this symbol
is not there. With this, modules built from a different
tree/version/configure will not be loaded.
The module loading code requires gmodule-2.0.
Signed-off-by: Fam Zheng <f...@redhat.com>
---
block.c | 1 +
configure | 29 +++++++++++++------
include/qemu/module.h | 23 +++++++++++++++
rules.mak | 2 +-
scripts/create_config | 14 ++++++++++
util/module.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++++++
vl.c | 2 ++
7 files changed, 138 insertions(+), 10 deletions(-)
diff --git a/block.c b/block.c
index 26639e8..16ceaaf 100644
--- a/block.c
+++ b/block.c
@@ -4008,6 +4008,7 @@ BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs,
void bdrv_init(void)
{
+ module_load(MODULE_LOAD_BLOCK);
module_call_init(MODULE_INIT_BLOCK);
}
diff --git a/configure b/configure
index 5bc7256..3043059 100755
--- a/configure
+++ b/configure
@@ -199,6 +199,7 @@ datadir="\${prefix}/share"
qemu_docdir="\${prefix}/share/doc/qemu"
bindir="\${prefix}/bin"
libdir="\${prefix}/lib"
+moddir="\${prefix}/lib/qemu"
libexecdir="\${prefix}/libexec"
includedir="\${prefix}/include"
sysconfdir="\${prefix}/etc"
@@ -676,6 +677,8 @@ for opt do
;;
--libdir=*) libdir="$optarg"
;;
+ --moddir=*) moddir="$optarg"
+ ;;
--libexecdir=*) libexecdir="$optarg"
;;
--includedir=*) includedir="$optarg"
@@ -1052,6 +1055,7 @@ echo " --datadir=PATH install firmware in
PATH$confsuffix"
echo " --docdir=PATH install documentation in PATH$confsuffix"
echo " --bindir=PATH install binaries in PATH"
echo " --libdir=PATH install libraries in PATH"
+echo " --moddir=PATH install modules in PATH"
echo " --sysconfdir=PATH install config in PATH$confsuffix"
echo " --localstatedir=PATH install local state in PATH (set at runtime
on win32)"
echo " --with-confsuffix=SUFFIX suffix for QEMU data inside datadir and
sysconfdir [$confsuffix]"
@@ -2256,15 +2260,19 @@ if test "$mingw32" = yes; then
else
glib_req_ver=2.12
fi
-if $pkg_config --atleast-version=$glib_req_ver gthread-2.0; then
- glib_cflags=`$pkg_config --cflags gthread-2.0`
- glib_libs=`$pkg_config --libs gthread-2.0`
- CFLAGS="$glib_cflags $CFLAGS"
- LIBS="$glib_libs $LIBS"
- libs_qga="$glib_libs $libs_qga"
-else
- error_exit "glib-$glib_req_ver required to compile QEMU"
-fi
+
+for i in gthread-2.0 gmodule-2.0; do
+ if $pkg_config --atleast-version=$glib_req_ver $i; then
+ glib_cflags=`$pkg_config --cflags $i`
+ glib_libs=`$pkg_config --libs $i`
+ CFLAGS="$glib_cflags $CFLAGS"
+ LIBS="$glib_libs $LIBS"
+ libs_qga="$glib_libs $libs_qga"
+ else
+ error_exit "glib-$glib_req_ver required to compile QEMU"
+ fi
+done
+
##########################################
# pixman support probe
@@ -3557,6 +3565,7 @@ echo "Install prefix $prefix"
echo "BIOS directory `eval echo $qemu_datadir`"
echo "binary directory `eval echo $bindir`"
echo "library directory `eval echo $libdir`"
+echo "module directory `eval echo $moddir`"
echo "libexec directory `eval echo $libexecdir`"
echo "include directory `eval echo $includedir`"
echo "config directory `eval echo $sysconfdir`"
@@ -3680,6 +3689,7 @@ echo all: >> $config_host_mak
echo "prefix=$prefix" >> $config_host_mak
echo "bindir=$bindir" >> $config_host_mak
echo "libdir=$libdir" >> $config_host_mak
+echo "moddir=$moddir" >> $config_host_mak
echo "libexecdir=$libexecdir" >> $config_host_mak
echo "includedir=$includedir" >> $config_host_mak
echo "mandir=$mandir" >> $config_host_mak
@@ -3698,6 +3708,7 @@ echo "libs_softmmu=$libs_softmmu" >> $config_host_mak
echo "ARCH=$ARCH" >> $config_host_mak
+echo "CONFIG_FINGERPRINT=$(date +%s$$$RANDOM)" >> $config_host_mak
if test "$modules" = "yes"; then
echo "CONFIG_MODULES=y" >> $config_host_mak
fi
diff --git a/include/qemu/module.h b/include/qemu/module.h
index c4ccd57..6458d8f 100644
--- a/include/qemu/module.h
+++ b/include/qemu/module.h
@@ -14,11 +14,25 @@
#ifndef QEMU_MODULE_H
#define QEMU_MODULE_H
+#ifdef BUILD_DSO
+
+/* For error message, this function is an identification of qemu module */
+void qemu_module_do_init(void (*init)(void));
+
+/* To restrict loading of arbitrary DSO, The init function name is changed per
+ * "./configure" to refuse unknown DSO file */
+void DSO_INIT_FUN(void);
+
+#define module_init(function, type) \
+void qemu_module_do_init(void (*init)(void)) { init(); } \
+void DSO_INIT_FUN(void) { qemu_module_do_init(function); }
+#else
/* This should not be used directly. Use block_init etc. instead. */
#define module_init(function, type) \
static void __attribute__((constructor)) do_qemu_init_ ## function(void) { \
register_module_init(function, type); \
}
+#endif
typedef enum {
MODULE_INIT_BLOCK,
@@ -37,4 +51,13 @@ void register_module_init(void (*fn)(void), module_init_type
type);
void module_call_init(module_init_type type);
+typedef enum {
+ MODULE_LOAD_BLOCK = 0,
+ MODULE_LOAD_UI,
+ MODULE_LOAD_NET,
+ MODULE_LOAD_MAX,
+} module_load_type;
+
+void module_load(module_load_type type);
+
#endif
diff --git a/rules.mak b/rules.mak
index 43a502e..0670366 100644
--- a/rules.mak
+++ b/rules.mak
@@ -62,7 +62,7 @@ endif
%.o: %.dtrace
$(call quiet-command,dtrace -o $@ -G -s $<, " GEN $(TARGET_DIR)$@")
-%$(DSOSUF): QEMU_CFLAGS += -fPIC
+%$(DSOSUF): QEMU_CFLAGS += -fPIC -DBUILD_DSO
%$(DSOSUF): LDFLAGS += $(LDFLAGS_SHARED)
%$(DSOSUF): %.mo libqemustub.a
$(call LINK,$^)
diff --git a/scripts/create_config b/scripts/create_config
index b1adbf5..ecc5d4d 100755
--- a/scripts/create_config
+++ b/scripts/create_config
@@ -26,6 +26,17 @@ case $line in
# save for the next definitions
prefix=${line#*=}
;;
+ moddir=*)
+ eval "moddir=\"${line#*=}\""
+ echo "#define CONFIG_MODDIR \"$moddir\""
+ ;;
+ CONFIG_FINGERPRINT=*)
+ echo "#define DSO_INIT_FUN init_${line#*=}"
+ echo "#define DSO_INIT_FUN_STR \"init_${line#*=}\""
+ ;;
+ CONFIG_MODULES=*)
+ echo "#define CONFIG_MODULES \"${line#*=}\""
+ ;;
CONFIG_AUDIO_DRIVERS=*)
drivers=${line#*=}
echo "#define CONFIG_AUDIO_DRIVERS \\"
@@ -104,6 +115,9 @@ case $line in
value=${line#*=}
echo "#define $name $value"
;;
+ DSOSUF=*)
+ echo "#define HOST_DSOSUF \"${line#*=}\""
+ ;;
esac
done # read
diff --git a/util/module.c b/util/module.c
index 7acc33d..9135c14 100644
--- a/util/module.c
+++ b/util/module.c
@@ -13,6 +13,8 @@
* GNU GPL, version 2 or (at your option) any later version.
*/
+#include <gmodule.h>
+#include <dirent.h>
#include "qemu-common.h"
#include "qemu/queue.h"
#include "qemu/module.h"
@@ -79,3 +81,78 @@ void module_call_init(module_init_type type)
e->init();
}
}
+
+#ifdef CONFIG_MODULES
+static void module_load_file(const char *fname)
+{
+ GModule *g_module;
+ void (*init_fun)(void);
+ const char *dsosuf = HOST_DSOSUF;
+ int len = strlen(fname);
+ int suf_len = strlen(dsosuf);
+
+ if (len <= suf_len || strcmp(&fname[len - suf_len], dsosuf)) {
+ /* wrong suffix */
+ return;
+ }
+ g_module = g_module_open(fname, G_MODULE_BIND_LAZY | G_MODULE_BIND_LOCAL);
+ if (!g_module) {
+ fprintf(stderr, "Failed to open module file %s\n",
+ g_module_error());
+ return;
+ }
+ if (!g_module_symbol(g_module, DSO_INIT_FUN_STR, (gpointer *)&init_fun)) {
+ fprintf(stderr, "Failed to initialize module: %s\n",
+ fname);
+ /* Print some info if this is a QEMU module (but from different build),
+ * this will make debugging user problems easier. */
+ if (g_module_symbol(g_module, "qemu_module_do_init",
+ (gpointer *)&init_fun)) {
+ fprintf(stderr,
+ "Note: only modules from the same build can be loaded.\n");
+ }
+ g_module_close(g_module);
+ return;
+ }
+ init_fun();
+}
+#endif
+
+void module_load(module_load_type type)
+{
+#ifdef CONFIG_MODULES
+ const char *path;
+ char *fname = NULL;
+ DIR *dp;
+ struct dirent *ep = NULL;
+
+ if (!g_module_supported()) {
+ return;
+ }
+
+ switch (type) {
+ case MODULE_LOAD_BLOCK:
+ path = CONFIG_MODDIR "/block/";
+ break;
+ case MODULE_LOAD_UI:
+ path = CONFIG_MODDIR "/ui/";
+ break;
+ case MODULE_LOAD_NET:
+ path = CONFIG_MODDIR "/net/";
+ break;
+ default:
+ return;
+ }
+
+ dp = opendir(path);
+ if (!dp) {
+ fprintf(stderr, "Failed to open dir %s\n", path);
+ return;
+ }
+ for (ep = readdir(dp); ep; ep = readdir(dp)) {
+ fname = g_strdup_printf("%s%s", path, ep->d_name);
+ module_load_file(fname);
+ g_free(fname);
+ }
+#endif
+}
diff --git a/vl.c b/vl.c
index b4b119a..659e53a 100644
--- a/vl.c
+++ b/vl.c
@@ -2940,6 +2940,8 @@ int main(int argc, char **argv, char **envp)
#endif
}
+ module_load(MODULE_LOAD_UI);
+ module_load(MODULE_LOAD_NET);
module_call_init(MODULE_INIT_QOM);
qemu_add_opts(&qemu_drive_opts);
--
1.8.3.1
