rust support build with O=

Signed-off-by: Finn Behrens <me@kloenk.de>

Author: kloenk

Makefile

@@ -513,7 +513,7 @@ KBUILD_RUSTCFLAGS :=
 # TODO: a simple way to update `Cargo.lock` when we add a new driver
 KBUILD_CARGOFLAGS := $(CARGO_VERBOSE) --locked \
 		    -Z build-std=core,alloc -Z unstable-options \
-		    --out-dir=out --target=$(PWD)/$(srctree)/arch/$(SRCARCH)/rust/target.json
+		    --target=$(srctree)/arch/$(SRCARCH)/rust/target.json
 KBUILD_AFLAGS_KERNEL :=
 KBUILD_CFLAGS_KERNEL :=
 KBUILD_RUSTCFLAGS_KERNEL :=

scripts/Makefile.build

@@ -307,25 +307,25 @@ $(obj)/%.lst: $(src)/%.c FORCE
 # ---------------------------------------------------------------------------
 
 quiet_cmd_cargo = CARGO $(quiet_modtag) $@
-      cmd_cargo = export RUST_BINDINGS_FILE=$(shell readlink -f $(srctree)/include/generated/rust_bindings.rs) && cd $(src) && $(CARGO) build $(cargo_flags)
+      cmd_cargo = export RUST_BINDINGS_FILE=$(shell readlink -f $(KCONFIG_RUSTC_CFG)) && $(CARGO) build --manifest-path $(srctree)/$(src)/Cargo.toml --out-dir $(src) $(cargo_flags)
 
-$(srctree)/include/generated/rust_bindings.rs: FORCE
+include/generated/rust_bindings.rs: FORCE
 	$(Q)$(BINDGEN) $(srctree)/rust/kernel/src/bindings_helper.h \
 		--opaque-type xregs_state \
 		--opaque-type desc_struct \
 		--use-core \
 		--with-derive-default \
 		--ctypes-prefix c_types \
 		--size_t-is-usize \
-		-o $(srctree)/include/generated/rust_bindings.rs \
+		-o $(KCONFIG_RUSTC_CFG) \
 		-- $(c_flags)
 
 # The .o from the Rust staticlib
-$(obj)/%.o: $(src)/out/lib%.a
+$(obj)/%.o: $(src)/lib%.a
 	$(Q)$(LD) -r -o $@ --whole-archive $<
 
 # The Rust staticlib from cargo
-$(obj)/out/lib%.a: $(srctree)/include/generated/rust_bindings.rs FORCE
+$(obj)/lib%.a: include/generated/rust_bindings.rs FORCE
 	$(call cmd,cargo)
 
 # Compile assembler sources (.S)

scripts/Makefile.lib

@@ -196,7 +196,7 @@ endif
 endif
 
 # TODO: quick hack
-part-of-module = $(if $(filter $(basename $@).o,$(real-obj-m)),y,$(and $(real-obj-m),$(shell echo $@ | sed -E 's!.+/out/lib.+\.a!y!;t;d')))
+part-of-module = $(if $(filter $(basename $@).o,$(real-obj-m)),y,$(and $(real-obj-m),$(shell echo $@ | sed -E 's!.+/lib.+\.a!y!;t;d')))
 quiet_modtag = $(if $(part-of-module),[M],   )
 
 modkern_cflags =                                          \
@@ -229,7 +229,7 @@ c_flags        = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
 RUST_BINDGEN_CFLAGS = $(c_flags) $(KBUILD_CFLAGS_MODULE)
 export RUST_BINDGEN_CFLAGS
 
-KCONFIG_RUSTC_CFG ?= $(srctree)/include/generated/rustc_cfg
+KCONFIG_RUSTC_CFG ?= ./include/generated/rustc_cfg
 
 rustc_flags     = $(_rustc_flags) $(modkern_rustcflags) @$(shell readlink -f $(KCONFIG_RUSTC_CFG))