usr/Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 #
   3 # kbuild file for usr/ - including initramfs image
   4 #
   5
   6 klibcdirs:;
   7 PHONY += klibcdirs
   8
   9 suffix_y = $(subst $\",,$(CONFIG_INITRAMFS_COMPRESSION))
  10 datafile_y = initramfs_data.cpio$(suffix_y)
  11 datafile_d_y = .$(datafile_y).d
  12 AFLAGS_initramfs_data.o += -DINITRAMFS_IMAGE="usr/$(datafile_y)"
  13
  14
  15 # Generate builtin.o based on initramfs_data.o
  16 obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o
  17
  18 # initramfs_data.o contains the compressed initramfs_data.cpio image.
  19 # The image is included using .incbin, a dependency which is not
  20 # tracked automatically.
  21 $(obj)/initramfs_data.o: $(obj)/$(datafile_y) FORCE
  22
  23 #####
  24 # Generate the initramfs cpio archive
  25
  26 hostprogs-y := gen_init_cpio
  27 initramfs   := $(CONFIG_SHELL) $(srctree)/$(src)/gen_initramfs_list.sh
  28 ramfs-input := $(if $(filter-out "",$(CONFIG_INITRAMFS_SOURCE)), \
  29                         $(shell echo $(CONFIG_INITRAMFS_SOURCE)),-d)
  30 ramfs-args  := \
  31         $(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
  32         $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID))
  33
  34 # $(datafile_d_y) is used to identify all files included
  35 # in initramfs and to detect if any files are added/removed.
  36 # Removed files are identified by directory timestamp being updated
  37 # The dependency list is generated by gen_initramfs.sh -l
  38 ifneq ($(wildcard $(obj)/$(datafile_d_y)),)
  39         include $(obj)/$(datafile_d_y)
  40 endif
  41
  42 quiet_cmd_initfs = GEN     $@
  43       cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)
  44
  45 targets := $(datafile_y)
  46
  47 # do not try to update files included in initramfs
  48 $(deps_initramfs): ;
  49
  50 $(deps_initramfs): klibcdirs
  51 # We rebuild initramfs_data.cpio if:
  52 # 1) Any included file is newer than initramfs_data.cpio
  53 # 2) There are changes in which files are included (added or deleted)
  54 # 3) If gen_init_cpio are newer than initramfs_data.cpio
  55 # 4) Arguments to gen_initramfs.sh changes
  56 $(obj)/$(datafile_y): $(obj)/gen_init_cpio $(deps_initramfs) klibcdirs
  57         $(Q)$(initramfs) -l $(ramfs-input) > $(obj)/$(datafile_d_y)
  58         $(call if_changed,initfs)
  59
  60 subdir-$(CONFIG_UAPI_HEADER_TEST) += include