From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56382) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bWoxZ-0003D5-3r for qemu-devel@nongnu.org; Mon, 08 Aug 2016 14:07:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bWoxW-0002Oo-7y for qemu-devel@nongnu.org; Mon, 08 Aug 2016 14:07:31 -0400 From: Colin Lord Date: Mon, 8 Aug 2016 14:07:19 -0400 Message-Id: <1470679640-18366-4-git-send-email-clord@redhat.com> In-Reply-To: <1470679640-18366-1-git-send-email-clord@redhat.com> References: <1470679640-18366-1-git-send-email-clord@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v7 3/4] blockdev: Add dynamic module loading for block drivers List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, qemu-block@nongnu.org, mreitz@redhat.com, Marc Mari , Colin Lord From: Marc Mari Extend the current module interface to allow for block drivers to be loaded dynamically on request. The only block drivers that can be converted into modules are the drivers that don't perform any init operation except for registering themselves. In addition, only the protocol drivers are being modularized, as they are the only ones which see significant performance benefits. The format drivers do not generally link to external libraries, so modularizing them is of no benefit from a performance perspective. All the necessary module information is located in a new structure found in module_block.h Signed-off-by: Marc Mar=C3=AD Signed-off-by: Colin Lord Reviewed-by: Stefan Hajnoczi --- Makefile | 3 --- block.c | 62 +++++++++++++++++++++++++++++++++++++++++++++= ------ block/Makefile.objs | 3 +-- include/qemu/module.h | 3 +++ util/module.c | 38 +++++++++---------------------- 5 files changed, 70 insertions(+), 39 deletions(-) diff --git a/Makefile b/Makefile index 4b9384e..c7aa8cd 100644 --- a/Makefile +++ b/Makefile @@ -247,9 +247,6 @@ Makefile: $(version-obj-y) $(version-lobj-y) libqemustub.a: $(stub-obj-y) libqemuutil.a: $(util-obj-y) =20 -block-modules =3D $(foreach o,$(block-obj-m),"$(basename $(subst /,-,$o)= )",) NULL -util/module.o-cflags =3D -D'CONFIG_BLOCK_MODULES=3D$(block-modules)' - ###################################################################### =20 qemu-img.o: qemu-img-cmds.h diff --git a/block.c b/block.c index 30d64e6..6c5e249 100644 --- a/block.c +++ b/block.c @@ -26,6 +26,7 @@ #include "block/block_int.h" #include "block/blockjob.h" #include "qemu/error-report.h" +#include "module_block.h" #include "qemu/module.h" #include "qapi/qmp/qerror.h" #include "qapi/qmp/qbool.h" @@ -241,17 +242,40 @@ BlockDriverState *bdrv_new(void) return bs; } =20 -BlockDriver *bdrv_find_format(const char *format_name) +static BlockDriver *bdrv_do_find_format(const char *format_name) { BlockDriver *drv1; + QLIST_FOREACH(drv1, &bdrv_drivers, list) { if (!strcmp(drv1->format_name, format_name)) { return drv1; } } + return NULL; } =20 +BlockDriver *bdrv_find_format(const char *format_name) +{ + BlockDriver *drv1; + size_t i; + + drv1 =3D bdrv_do_find_format(format_name); + if (drv1) { + return drv1; + } + + /* The driver isn't registered, maybe we need to load a module */ + for (i =3D 0; i < ARRAY_SIZE(block_driver_modules); ++i) { + if (!strcmp(block_driver_modules[i].format_name, format_name)) { + block_module_load_one(block_driver_modules[i].library_name); + break; + } + } + + return bdrv_do_find_format(format_name); +} + static int bdrv_is_whitelisted(BlockDriver *drv, bool read_only) { static const char *whitelist_rw[] =3D { @@ -460,6 +484,19 @@ static BlockDriver *find_hdev_driver(const char *fil= ename) return drv; } =20 +static BlockDriver *bdrv_do_find_protocol(const char *protocol) +{ + BlockDriver *drv1; + + QLIST_FOREACH(drv1, &bdrv_drivers, list) { + if (drv1->protocol_name && !strcmp(drv1->protocol_name, protocol= )) { + return drv1; + } + } + + return NULL; +} + BlockDriver *bdrv_find_protocol(const char *filename, bool allow_protocol_prefix, Error **errp) @@ -468,6 +505,7 @@ BlockDriver *bdrv_find_protocol(const char *filename, char protocol[128]; int len; const char *p; + size_t i; =20 /* TODO Drivers without bdrv_file_open must be specified explicitly = */ =20 @@ -494,15 +532,25 @@ BlockDriver *bdrv_find_protocol(const char *filenam= e, len =3D sizeof(protocol) - 1; memcpy(protocol, filename, len); protocol[len] =3D '\0'; - QLIST_FOREACH(drv1, &bdrv_drivers, list) { - if (drv1->protocol_name && - !strcmp(drv1->protocol_name, protocol)) { - return drv1; + + drv1 =3D bdrv_do_find_protocol(protocol); + if (drv1) { + return drv1; + } + + for (i =3D 0; i < ARRAY_SIZE(block_driver_modules); ++i) { + if (block_driver_modules[i].protocol_name && + !strcmp(block_driver_modules[i].protocol_name, protocol)) { + block_module_load_one(block_driver_modules[i].library_name); + break; } } =20 - error_setg(errp, "Unknown protocol '%s'", protocol); - return NULL; + drv1 =3D bdrv_do_find_protocol(protocol); + if (!drv1) { + error_setg(errp, "Unknown protocol '%s'", protocol); + } + return drv1; } =20 /* diff --git a/block/Makefile.objs b/block/Makefile.objs index 2593a2f..595f366 100644 --- a/block/Makefile.objs +++ b/block/Makefile.objs @@ -1,4 +1,4 @@ -block-obj-y +=3D raw_bsd.o qcow.o vdi.o vmdk.o cloop.o bochs.o vpc.o vvf= at.o +block-obj-y +=3D raw_bsd.o qcow.o vdi.o vmdk.o cloop.o bochs.o vpc.o vvf= at.o dmg.o block-obj-y +=3D qcow2.o qcow2-refcount.o qcow2-cluster.o qcow2-snapshot= .o qcow2-cache.o block-obj-y +=3D qed.o qed-gencb.o qed-l2-cache.o qed-table.o qed-cluste= r.o block-obj-y +=3D qed-check.o @@ -39,7 +39,6 @@ gluster.o-libs :=3D $(GLUSTERFS_LIBS) ssh.o-cflags :=3D $(LIBSSH2_CFLAGS) ssh.o-libs :=3D $(LIBSSH2_LIBS) archipelago.o-libs :=3D $(ARCHIPELAGO_LIBS) -block-obj-m +=3D dmg.o dmg.o-libs :=3D $(BZIP2_LIBS) qcow.o-libs :=3D -lz linux-aio.o-libs :=3D -laio diff --git a/include/qemu/module.h b/include/qemu/module.h index 2370708..dc2c9d4 100644 --- a/include/qemu/module.h +++ b/include/qemu/module.h @@ -52,9 +52,12 @@ typedef enum { #define qapi_init(function) module_init(function, MODULE_INIT_QAPI) #define type_init(function) module_init(function, MODULE_INIT_QOM) =20 +#define block_module_load_one(lib) module_load_one("block-", lib) + void register_module_init(void (*fn)(void), module_init_type type); void register_dso_module_init(void (*fn)(void), module_init_type type); =20 void module_call_init(module_init_type type); +void module_load_one(const char *prefix, const char *lib_name); =20 #endif diff --git a/util/module.c b/util/module.c index 86e3f7a..a5f7fbd 100644 --- a/util/module.c +++ b/util/module.c @@ -87,14 +87,11 @@ void register_dso_module_init(void (*fn)(void), modul= e_init_type type) QTAILQ_INSERT_TAIL(&dso_init_list, e, node); } =20 -static void module_load(module_init_type type); - void module_call_init(module_init_type type) { ModuleTypeList *l; ModuleEntry *e; =20 - module_load(type); l =3D find_type(type); =20 QTAILQ_FOREACH(e, l, node) { @@ -145,6 +142,7 @@ static int module_load_file(const char *fname) ret =3D -EINVAL; } else { QTAILQ_FOREACH(e, &dso_init_list, node) { + e->init(); register_module_init(e->init, e->type); } ret =3D 0; @@ -159,14 +157,10 @@ out: } #endif =20 -static void module_load(module_init_type type) +void module_load_one(const char *prefix, const char *lib_name) { #ifdef CONFIG_MODULES char *fname =3D NULL; - const char **mp; - static const char *block_modules[] =3D { - CONFIG_BLOCK_MODULES - }; char *exec_dir; char *dirs[3]; int i =3D 0; @@ -177,15 +171,6 @@ static void module_load(module_init_type type) return; } =20 - switch (type) { - case MODULE_INIT_BLOCK: - mp =3D block_modules; - break; - default: - /* no other types have dynamic modules for now*/ - return; - } - exec_dir =3D qemu_get_exec_dir(); dirs[i++] =3D g_strdup_printf("%s", CONFIG_QEMU_MODDIR); dirs[i++] =3D g_strdup_printf("%s/..", exec_dir ? : ""); @@ -194,16 +179,15 @@ static void module_load(module_init_type type) g_free(exec_dir); exec_dir =3D NULL; =20 - for ( ; *mp; mp++) { - for (i =3D 0; i < ARRAY_SIZE(dirs); i++) { - fname =3D g_strdup_printf("%s/%s%s", dirs[i], *mp, HOST_DSOS= UF); - ret =3D module_load_file(fname); - g_free(fname); - fname =3D NULL; - /* Try loading until loaded a module file */ - if (!ret) { - break; - } + for (i =3D 0; i < ARRAY_SIZE(dirs); i++) { + fname =3D g_strdup_printf("%s/%s%s%s", + dirs[i], prefix, lib_name, HOST_DSOSUF); + ret =3D module_load_file(fname); + g_free(fname); + fname =3D NULL; + /* Try loading until loaded a module file */ + if (!ret) { + break; } } =20 --=20 2.5.5