config: kernel: Add support for configuring BTRFS to be built-in

Add the KERNEL_BTRFS_FS config option so that targets can select
whether BTRFS support must be built-in.

Select this option (alongside KERNEL_BTRFS_FS_POSIX_ACL) from the
layerscape/armv8_64b subtarget instead of enabling it in
target/linux/layerscape/armv8_64b/config-* files.

Move disabling of CONFIG_BTRFS_FS_CHECK_INTEGRITY into generic configs.

This makes it possible for OpenWRT to be built with built-in BTRFS
support on specific boards, instead of whole targets.

Signed-off-by: Marek Behún <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/15990
Signed-off-by: Hauke Mehrtens <[email protected]>

config/Config-kernel.in

@@ -1238,6 +1238,12 @@ if KERNEL_IP_PNP
 
 endif
 
+config KERNEL_BTRFS_FS
+	bool "Compile the kernel with built-in BTRFS support"
+	help
+	  Say Y here if you want to make the kernel to be able to boot off a
+	  BTRFS partition.
+
 menu "Filesystem ACL and attr support options"
 	config USE_FS_ACL_ATTR
 		bool "Use filesystem ACL and attr support by default"

target/linux/generic/config-5.15

@@ -774,6 +774,7 @@ CONFIG_BROKEN_ON_SMP=y
 # CONFIG_BTRFS_ASSERT is not set
 # CONFIG_BTRFS_DEBUG is not set
 # CONFIG_BTRFS_FS is not set
+# CONFIG_BTRFS_FS_CHECK_INTEGRITY is not set
 # CONFIG_BTRFS_FS_POSIX_ACL is not set
 # CONFIG_BTRFS_FS_REF_VERIFY is not set
 # CONFIG_BTRFS_FS_RUN_SANITY_TESTS is not set

target/linux/generic/config-6.1

@@ -820,6 +820,7 @@ CONFIG_BROKEN_ON_SMP=y
 # CONFIG_BTRFS_ASSERT is not set
 # CONFIG_BTRFS_DEBUG is not set
 # CONFIG_BTRFS_FS is not set
+# CONFIG_BTRFS_FS_CHECK_INTEGRITY is not set
 # CONFIG_BTRFS_FS_POSIX_ACL is not set
 # CONFIG_BTRFS_FS_REF_VERIFY is not set
 # CONFIG_BTRFS_FS_RUN_SANITY_TESTS is not set

target/linux/generic/config-6.6

@@ -725,6 +725,7 @@ CONFIG_BROKEN_ON_SMP=y
 # CONFIG_BTRFS_ASSERT is not set
 # CONFIG_BTRFS_DEBUG is not set
 # CONFIG_BTRFS_FS is not set
+# CONFIG_BTRFS_FS_CHECK_INTEGRITY is not set
 # CONFIG_BTRFS_FS_POSIX_ACL is not set
 # CONFIG_BTRFS_FS_REF_VERIFY is not set
 # CONFIG_BTRFS_FS_RUN_SANITY_TESTS is not set

target/linux/layerscape/armv8_64b/config-6.1

@@ -104,9 +104,6 @@ CONFIG_BLK_MQ_VIRTIO=y
 CONFIG_BLK_PM=y
 CONFIG_BSD_PROCESS_ACCT=y
 CONFIG_BSD_PROCESS_ACCT_V3=y
-CONFIG_BTRFS_FS=y
-# CONFIG_BTRFS_FS_CHECK_INTEGRITY is not set
-CONFIG_BTRFS_FS_POSIX_ACL=y
 CONFIG_CAVIUM_ERRATUM_22375=y
 CONFIG_CAVIUM_ERRATUM_23144=y
 CONFIG_CAVIUM_ERRATUM_23154=y

target/linux/layerscape/armv8_64b/config-6.6

@@ -105,9 +105,6 @@ CONFIG_BLK_MQ_VIRTIO=y
 CONFIG_BLK_PM=y
 CONFIG_BSD_PROCESS_ACCT=y
 CONFIG_BSD_PROCESS_ACCT_V3=y
-CONFIG_BTRFS_FS=y
-# CONFIG_BTRFS_FS_CHECK_INTEGRITY is not set
-CONFIG_BTRFS_FS_POSIX_ACL=y
 CONFIG_BUFFER_HEAD=y
 CONFIG_BUILTIN_RETURN_ADDRESS_STRIPS_PAC=y
 CONFIG_CAVIUM_ERRATUM_22375=y

target/linux/layerscape/armv8_64b/target.mk

@@ -5,6 +5,7 @@
 ARCH:=aarch64
 BOARDNAME:=ARMv8 64-bit based boards
 KERNELNAME:=Image dtbs
+DEPENDS:=+@KERNEL_BTRFS_FS +@KERNEL_BTRFS_FS_POSIX_ACL
 
 define Target/Description
 	Build firmware images for NXP Layerscape ARMv8 64-bit based boards.