[Qemu-devel] [PATCH PULL v3 03/11] crypto: move crypto objects out of libqemuutil.la

["Daniel P. Berrange" <berrange@redhat.com>]

Future patches will be adding more crypto related APIs which
rely on QOM infrastructure. This creates a problem, because
QOM relies on library constructors to register objects. When
you have a file in a static .a library though which is only
referenced by a constructor the linker is dumb and will drop
that file when linking to the final executable :-( The only
workaround for this is to link the .a library to the executable
using the -Wl,--whole-archive flag, but this creates its own
set of problems because QEMU is relying on lazy linking for
libqemuutil.a. Using --whole-archive majorly increases the
size of final executables as they now contain a bunch of
object code they don't actually use.

The least bad option is to thus not include the crypto objects
in libqemuutil.la, and instead define a crypto-obj-y variable
that is referenced directly by all the executables that need
this code (tools + softmmu, but not qemu-ga). We avoid pulling
entire of crypto-obj-y into the userspace emulators as that
would force them to link to gnutls too, which is not required.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 Makefile             |  9 ++++++---
 Makefile.objs        |  6 +++++-
 Makefile.target      |  4 ++++
 crypto/Makefile.objs | 13 ++++++++-----
 tests/Makefile       |  7 ++++---
 5 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/Makefile b/Makefile
index 9ce3972..9c08b11 100644
--- a/Makefile
+++ b/Makefile
@@ -152,6 +152,8 @@ dummy := $(call unnest-vars,, \
                 qga-vss-dll-obj-y \
                 block-obj-y \
                 block-obj-m \
+                crypto-obj-y \
+                crypto-aes-obj-y \
                 common-obj-y \
                 common-obj-m)
 
@@ -173,6 +175,7 @@ SUBDIR_RULES=$(patsubst %,subdir-%, $(TARGET_DIRS))
 SOFTMMU_SUBDIR_RULES=$(filter %-softmmu,$(SUBDIR_RULES))
 
 $(SOFTMMU_SUBDIR_RULES): $(block-obj-y)
+$(SOFTMMU_SUBDIR_RULES): $(crypto-obj-y)
 $(SOFTMMU_SUBDIR_RULES): config-all-devices.mak
 
 subdir-%:
@@ -227,9 +230,9 @@ util/module.o-cflags = -D'CONFIG_BLOCK_MODULES=$(block-modules)'
 
 qemu-img.o: qemu-img-cmds.h
 
-qemu-img$(EXESUF): qemu-img.o $(block-obj-y) libqemuutil.a libqemustub.a
-qemu-nbd$(EXESUF): qemu-nbd.o $(block-obj-y) libqemuutil.a libqemustub.a
-qemu-io$(EXESUF): qemu-io.o $(block-obj-y) libqemuutil.a libqemustub.a
+qemu-img$(EXESUF): qemu-img.o $(block-obj-y) $(crypto-obj-y) libqemuutil.a libqemustub.a
+qemu-nbd$(EXESUF): qemu-nbd.o $(block-obj-y) $(crypto-obj-y) libqemuutil.a libqemustub.a
+qemu-io$(EXESUF): qemu-io.o $(block-obj-y) $(crypto-obj-y) libqemuutil.a libqemustub.a
 
 qemu-bridge-helper$(EXESUF): qemu-bridge-helper.o
 
diff --git a/Makefile.objs b/Makefile.objs
index f094eff..655c1f0 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -2,7 +2,6 @@
 # Common libraries for tools and emulators
 stub-obj-y = stubs/
 util-obj-y = util/ qobject/ qapi/ qapi-types.o qapi-visit.o qapi-event.o
-util-obj-y += crypto/
 
 #######################################################################
 # block-obj-y is code used by both qemu system emulation and qemu-img
@@ -21,6 +20,11 @@ block-obj-y += coroutine-$(CONFIG_COROUTINE_BACKEND).o
 
 block-obj-m = block/
 
+#######################################################################
+# crypto-obj-y is code used by both qemu system emulation and qemu-img
+
+crypto-obj-y = crypto/
+crypto-aes-obj-y = crypto/
 
 ######################################################################
 # smartcard
diff --git a/Makefile.target b/Makefile.target
index dc32294..3d97966 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -170,12 +170,16 @@ target-obj-y-save := $(target-obj-y)
 dummy := $(call unnest-vars,.., \
                block-obj-y \
                block-obj-m \
+               crypto-obj-y \
+               crypto-aes-obj-y \
                common-obj-y \
                common-obj-m)
 target-obj-y := $(target-obj-y-save)
 all-obj-y += $(common-obj-y)
 all-obj-y += $(target-obj-y)
 all-obj-$(CONFIG_SOFTMMU) += $(block-obj-y)
+all-obj-$(CONFIG_USER_ONLY) += $(crypto-aes-obj-y)
+all-obj-$(CONFIG_SOFTMMU) += $(crypto-obj-y)
 
 $(QEMU_PROG_BUILD): config-devices.mak
 
diff --git a/crypto/Makefile.objs b/crypto/Makefile.objs
index b050138..2167fd2 100644
--- a/crypto/Makefile.objs
+++ b/crypto/Makefile.objs
@@ -1,5 +1,8 @@
-util-obj-y += init.o
-util-obj-y += hash.o
-util-obj-y += aes.o
-util-obj-y += desrfb.o
-util-obj-y += cipher.o
+crypto-obj-y = init.o
+crypto-obj-y += hash.o
+crypto-obj-y += aes.o
+crypto-obj-y += desrfb.o
+crypto-obj-y += cipher.o
+
+# Let the userspace emulators avoid linking gnutls/etc
+crypto-aes-obj-y = aes.o
diff --git a/tests/Makefile b/tests/Makefile
index 0fcf148..d77ccee 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -290,7 +290,8 @@ test-qom-obj-y = qom/object.o qom/qom-qobject.o \
 test-qapi-obj-y = tests/test-qapi-visit.o tests/test-qapi-types.o \
 	tests/test-qapi-event.o \
 	$(test-qom-obj-y)
-test-block-obj-y = $(block-obj-y) $(test-util-obj-y)
+test-crypto-obj-y = $(crypto-obj-y) $(test-util-obj-y)
+test-block-obj-y = $(block-obj-y) $(test-crypto-obj-y)
 
 tests/check-qint$(EXESUF): tests/check-qint.o $(test-util-obj-y)
 tests/check-qstring$(EXESUF): tests/check-qstring.o $(test-util-obj-y)
@@ -357,8 +358,8 @@ tests/test-opts-visitor$(EXESUF): tests/test-opts-visitor.o $(test-qapi-obj-y)
 
 tests/test-mul64$(EXESUF): tests/test-mul64.o $(test-util-obj-y)
 tests/test-bitops$(EXESUF): tests/test-bitops.o $(test-util-obj-y)
-tests/test-crypto-hash$(EXESUF): tests/test-crypto-hash.o $(test-util-obj-y)
-tests/test-crypto-cipher$(EXESUF): tests/test-crypto-cipher.o $(test-util-obj-y)
+tests/test-crypto-hash$(EXESUF): tests/test-crypto-hash.o $(test-crypto-obj-y)
+tests/test-crypto-cipher$(EXESUF): tests/test-crypto-cipher.o $(test-crypto-obj-y)
 
 libqos-obj-y = tests/libqos/pci.o tests/libqos/fw_cfg.o tests/libqos/malloc.o
 libqos-obj-y += tests/libqos/i2c.o tests/libqos/libqos.o
-- 
2.4.3