[PATCH RESEND v11 13/13] um: nommu: plug nommu code into build system

[Hajime Tazaki <thehajime@gmail.com>]

Add nommu kernel for um build.  defconfig is also provided.

Signed-off-by: Hajime Tazaki <thehajime@gmail.com>
Signed-off-by: Ricardo Koller <ricarkol@google.com>
---
 arch/um/Kconfig                        | 14 ++++++-
 arch/um/configs/x86_64_nommu_defconfig | 54 ++++++++++++++++++++++++++
 2 files changed, 66 insertions(+), 2 deletions(-)
 create mode 100644 arch/um/configs/x86_64_nommu_defconfig

diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index 8161cc5ae6f7..b3d2716836ac 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -32,16 +32,19 @@ config UML
 	select ARCH_SUPPORTS_LTO_CLANG_THIN
 	select TRACE_IRQFLAGS_SUPPORT
 	select TTY # Needed for line.c
-	select HAVE_ARCH_VMAP_STACK
+	select HAVE_ARCH_VMAP_STACK if MMU
 	select HAVE_RUST
 	select ARCH_HAS_UBSAN
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_SYSCALL_TRACEPOINTS
 	select THREAD_INFO_IN_TASK
 	select SPARSE_IRQ
+	select UACCESS_MEMCPY if !MMU
+	select GENERIC_STRNLEN_USER if !MMU
+	select GENERIC_STRNCPY_FROM_USER if !MMU
 
 config MMU
-	bool
+	bool "MMU-based Paged Memory Management Support" if 64BIT
 	default y
 
 config UML_DMA_EMULATION
@@ -185,8 +188,15 @@ config MAGIC_SYSRQ
 	  The keys are documented in <file:Documentation/admin-guide/sysrq.rst>. Don't say Y
 	  unless you really know what this hack does.
 
+config ARCH_FORCE_MAX_ORDER
+	int "Order of maximal physically contiguous allocations" if EXPERT
+	default "10" if MMU
+	default "16" if !MMU
+
 config KERNEL_STACK_ORDER
 	int "Kernel stack size order"
+	default 3 if !MMU
+	range 3 10 if !MMU
 	default 2 if 64BIT
 	range 2 10 if 64BIT
 	default 1 if !64BIT
diff --git a/arch/um/configs/x86_64_nommu_defconfig b/arch/um/configs/x86_64_nommu_defconfig
new file mode 100644
index 000000000000..02cb87091c9f
--- /dev/null
+++ b/arch/um/configs/x86_64_nommu_defconfig
@@ -0,0 +1,54 @@
+CONFIG_SYSVIPC=y
+CONFIG_POSIX_MQUEUE=y
+CONFIG_NO_HZ=y
+CONFIG_HIGH_RES_TIMERS=y
+CONFIG_BSD_PROCESS_ACCT=y
+CONFIG_IKCONFIG=y
+CONFIG_IKCONFIG_PROC=y
+CONFIG_LOG_BUF_SHIFT=14
+CONFIG_CGROUPS=y
+CONFIG_BLK_CGROUP=y
+CONFIG_CGROUP_SCHED=y
+CONFIG_CGROUP_DEVICE=y
+CONFIG_CGROUP_CPUACCT=y
+# CONFIG_PID_NS is not set
+CONFIG_CC_OPTIMIZE_FOR_SIZE=y
+# CONFIG_MMU is not set
+CONFIG_HOSTFS=y
+CONFIG_MAGIC_SYSRQ=y
+CONFIG_SSL=y
+CONFIG_NULL_CHAN=y
+CONFIG_PORT_CHAN=y
+CONFIG_PTY_CHAN=y
+CONFIG_TTY_CHAN=y
+CONFIG_CON_CHAN="pts"
+CONFIG_SSL_CHAN="pts"
+CONFIG_MODULES=y
+CONFIG_MODULE_UNLOAD=y
+CONFIG_IOSCHED_BFQ=m
+CONFIG_BINFMT_MISC=m
+CONFIG_NET=y
+CONFIG_PACKET=y
+CONFIG_UNIX=y
+CONFIG_INET=y
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
+CONFIG_BLK_DEV_UBD=y
+CONFIG_BLK_DEV_LOOP=m
+CONFIG_BLK_DEV_NBD=m
+CONFIG_DUMMY=m
+CONFIG_TUN=m
+CONFIG_PPP=m
+CONFIG_SLIP=m
+CONFIG_LEGACY_PTY_COUNT=32
+CONFIG_UML_RANDOM=y
+CONFIG_EXT4_FS=y
+CONFIG_QUOTA=y
+CONFIG_AUTOFS_FS=m
+CONFIG_ISO9660_FS=m
+CONFIG_JOLIET=y
+CONFIG_NLS=y
+CONFIG_DEBUG_KERNEL=y
+CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
+CONFIG_FRAME_WARN=1024
+CONFIG_IPV6=y
-- 
2.43.0