With this patch libraries can amend the master linker script by
registering the extra script in EXTRA_LD_SCRIPT-y variable.
See doc/guides/developers-app.rst for details.
Signed-off-by: Yuri Volchkov <yuri.volchkov@xxxxxxxxx>
---
doc/guides/developers-app.rst | 26 ++++++++++++++++++++++++++
plat/kvm/Linker.uk | 5 ++++-
plat/linuxu/Linker.uk | 2 ++
plat/xen/Linker.uk | 8 ++++++--
4 files changed, 38 insertions(+), 3 deletions(-)
diff --git a/doc/guides/developers-app.rst
b/doc/guides/developers-app.rst
index 97ed2451..5919ab73 100644
--- a/doc/guides/developers-app.rst
+++ b/doc/guides/developers-app.rst
@@ -31,6 +31,9 @@ you need to provide at least the following four files:
usually contains only `main` for an application that is
developed/ported
as a single library to Unikraft.
+ * **extra.ld**: Optional. Contains an amendment to the main linker
+ script
+
The Makefile is generally short and simple and might remind you to
Linux kernel modules that are built off-tree. For most applications
the Makefile should contain no more than the following: ::
@@ -293,6 +296,29 @@ is part of a remotely fetched archive). You can
override it by defining the
with ``$(APPNAME_BASE)`` to the base directory of your application
sources) or
relative to the Unikraft sources directory.
+============================
+extra.ld
+============================
+If your library/application needs a section in the final elf, edit
+your Makefile.uk to add ::
+
+ EXTRA_LD_SCRIPT-$(CONFIG_LIBYOURAPPNAME) +=
$(LIBYOURAPPNAME_BASE)/extra.ld
+
+
+An example context of extra.ld: ::
+
+ SECTIONS
+ {
+ .uk_fs_list : {
+ PROVIDE(uk_fslist_start = .);
+ KEEP (*(.uk_fs_list))
+ PROVIDE(uk_fslist_end = .);
+ }
+ }
+ INSERT AFTER .text;
+
+This will add section .uk_fs_list after the .text
+
============================
Make Targets
diff --git a/plat/kvm/Linker.uk b/plat/kvm/Linker.uk
index e0a56774..4587daf7 100644
--- a/plat/kvm/Linker.uk
+++ b/plat/kvm/Linker.uk
@@ -13,6 +13,8 @@ endif
##
KVM_IMAGE := $(BUILD_DIR)/$(CONFIG_UK_NAME)_kvm-$(CONFIG_UK_ARCH)
+EXTRA_LD_SCRIPT_FLAGS := $(addprefix -Wl$(comma)-T,$(EXTRA_LD_SCRIPT-y))
+
$(KVM_IMAGE): $(KVM_ALIBS) $(KVM_ALIBS-y) $(KVM_OLIBS) $(KVM_OLIBS-y) \
$(UK_ALIBS) $(UK_ALIBS-y) $(UK_OLIBS) $(UK_OLIBS-y) \
$(KVM_LDSCRIPT)
@@ -32,7 +34,8 @@ ifneq ($(filter x86_64 arm64,$(CONFIG_UK_ARCH)),)
$(call build_cmd,LD,,$@,\
$(LD) $(LDFLAGS) $(LDFLAGS-y) \
$(KVM_LDFLAGS) $(KVM_LDFLAGS-y) \
- -Wl$(comma)-T$(comma)$(call strip,$(KVM_LDSCRIPT)) \
+ -Wl$(comma)-dT$(comma)$(call strip,$(KVM_LDSCRIPT)) \
+ $(EXTRA_LD_SCRIPT_FLAGS) \
$@.o -o $@)
ifeq ($(CONFIG_OPTIMIZE_DBGFILE),y)
$(call build_cmd,OBJCOPY,,$@.dbg,\
diff --git a/plat/linuxu/Linker.uk b/plat/linuxu/Linker.uk
index 9e4b2a9d..dbdf9d96 100644
--- a/plat/linuxu/Linker.uk
+++ b/plat/linuxu/Linker.uk
@@ -4,6 +4,7 @@ LINUXU_LDFLAGS-y += -Wl,-e,_liblinuxuplat_start
## Link image
##
LINUXU_IMAGE := $(BUILD_DIR)/$(CONFIG_UK_NAME)_linuxu-$(CONFIG_UK_ARCH)
+EXTRA_LD_SCRIPT_FLAGS := $(addprefix -Wl$(comma)-T,$(EXTRA_LD_SCRIPT-y))
$(LINUXU_IMAGE): $(LINUXU_ALIBS) $(LINUXU_ALIBS-y) \
$(LINUXU_OLIBS) $(LINUXU_OLIBS-y) \
@@ -17,6 +18,7 @@ $(LINUXU_IMAGE): $(LINUXU_ALIBS) $(LINUXU_ALIBS-y) \
$(LINUXU_ALIBS) $(LINUXU_ALIBS-y) \
$(UK_ALIBS) $(UK_ALIBS-y) \
-Wl$(comma)--end-group \
+ $(EXTRA_LD_SCRIPT_FLAGS) \
-o $@)
ifeq ($(CONFIG_OPTIMIZE_DBGFILE),y)
$(call build_cmd,OBJCOPY,,$@.dbg,\
diff --git a/plat/xen/Linker.uk b/plat/xen/Linker.uk
index df84c20f..801f5e2e 100644
--- a/plat/xen/Linker.uk
+++ b/plat/xen/Linker.uk
@@ -18,6 +18,8 @@ endif
##
XEN_IMAGE := $(BUILD_DIR)/$(CONFIG_UK_NAME)_xen-$(CONFIG_UK_ARCH)
+EXTRA_LD_SCRIPT_FLAGS := $(addprefix -Wl$(comma)-T,$(EXTRA_LD_SCRIPT-y))
+
$(XEN_IMAGE): $(XEN_ALIBS) $(XEN_ALIBS-y) $(XEN_OLIBS) $(XEN_OLIBS-y) \
$(UK_ALIBS) $(UK_ALIBS-y) $(UK_OLIBS) $(UK_OLIBS-y) \
$(XEN_LDSCRIPT)
@@ -36,7 +38,8 @@ $(XEN_IMAGE): $(XEN_ALIBS) $(XEN_ALIBS-y)
$(XEN_OLIBS) $(XEN_OLIBS-y) \
ifeq (arm,$(CONFIG_UK_ARCH))
$(call build_cmd,LD,,$@.elf,\
$(LD) $(LDFLAGS) $(LDFLAGS-y) $(XEN_LDFLAGS)
$(XEN_LDFLAGS-y) \
- -Wl$(comma)-T$(comma)$(call strip,$(XEN_LDSCRIPT)) \
+ -Wl$(comma)-dT$(comma)$(call strip,$(XEN_LDSCRIPT)) \
+ $(EXTRA_LD_SCRIPT_FLAGS) \
$@.o -o $@.elf)
ifeq ($(CONFIG_OPTIMIZE_DBGFILE),y)
$(call build_cmd,OBJCOPY,,$@.dbg,\
@@ -57,7 +60,8 @@ endif
else
$(call build_cmd,LD,,$@,\
$(LD) $(LDFLAGS) $(LDFLAGS-y) $(XEN_LDFLAGS)
$(XEN_LDFLAGS-y) \
- -Wl$(comma)-T$(comma)$(call strip,$(XEN_LDSCRIPT)) \
+ -Wl$(comma)-dT$(comma)$(call strip,$(XEN_LDSCRIPT)) \
+ $(EXTRA_LD_SCRIPT_FLAGS) \
$@.o -o $@)
ifeq ($(CONFIG_OPTIMIZE_DBGFILE),y)
$(call build_cmd,OBJCOPY,,$@.dbg,\
