autoconf: Pretend CONFIG_MODULES is always on

- Unconditionally inject `CONFIG_MODULES` make variable
  and `#define CONFIG_MODULES` to Kbuild in `ZFS_LINUX_COMPILE`
  autoconf function to emulate loadable kernel modules support.
  This allows OpenZFS to perform Linux checks despite
  `CONFIG_MODULES=n` in the actual Linux config.

- Add `ZFS_AC_KERNEL_CONFIG_MODULES` check which encompasses
  the logic from `ZFS_AC_KERNEL_TEST_MODULE` with additional
  diagnostic messages to the user

- Removed `ZFS_AC_KERNEL_TEST_MODULE` as it merely duplicates
  every check in `ZFS_AC_KERNEL_CONFIG_DEFINED`

- Moved `ZFS_AC_MODULE_SYMVERS` after `ZFS_AC_KERNEL_CONFIG_DEFINED`
  so the user has a chance to see the proper diagnostic from the
  steps before.

A workaround for Linux's

```
commit 3e3005df73b535cb849cf4ec8075d6aa3c460f68
Author: Masahiro Yamada <masahiroy@kernel.org>
Date:   Wed Mar 31 22:38:03 2021 +0900

kbuild: unify modules(_install) for in-tree and external modules

If you attempt to build or install modules ('make modules(_install)'
with CONFIG_MODULES disabled, you will get a clear error message, but
nothing for external module builds.

Factor out the modules and modules_install rules into the common part,
so you will get the same error message when you try to build external
modules with CONFIG_MODULES=n.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
```

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: szubersk <szuberskidamian@gmail.com>
Closes #10832
Closes #13361
This commit is contained in:
Damian Szuberski 2022-04-27 03:47:09 +10:00 committed by GitHub
parent 600a02b884
commit a0dfd98a25
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 62 additions and 26 deletions

View File

@ -19,6 +19,7 @@ AC_DEFUN([ZFS_AC_KERNEL_CONFIG_DEFINED], [
])
])
ZFS_AC_KERNEL_SRC_CONFIG_MODULES
ZFS_AC_KERNEL_SRC_CONFIG_BLOCK
ZFS_AC_KERNEL_SRC_CONFIG_DEBUG_LOCK_ALLOC
ZFS_AC_KERNEL_SRC_CONFIG_TRIM_UNUSED_KSYMS
@ -29,6 +30,7 @@ AC_DEFUN([ZFS_AC_KERNEL_CONFIG_DEFINED], [
ZFS_LINUX_TEST_COMPILE_ALL([config])
AC_MSG_RESULT([done])
ZFS_AC_KERNEL_CONFIG_MODULES
ZFS_AC_KERNEL_CONFIG_BLOCK
ZFS_AC_KERNEL_CONFIG_DEBUG_LOCK_ALLOC
ZFS_AC_KERNEL_CONFIG_TRIM_UNUSED_KSYMS
@ -99,6 +101,61 @@ AC_DEFUN([ZFS_AC_KERNEL_CONFIG_DEBUG_LOCK_ALLOC], [
])
])
dnl #
dnl # Check CONFIG_MODULES
dnl #
dnl # Verify the kernel has CONFIG_MODULES support enabled.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_CONFIG_MODULES], [
ZFS_LINUX_TEST_SRC([config_modules], [
#if !defined(CONFIG_MODULES)
#error CONFIG_MODULES not defined
#endif
],[])
])
AC_DEFUN([ZFS_AC_KERNEL_CONFIG_MODULES], [
AC_MSG_CHECKING([whether CONFIG_MODULES is defined])
AS_IF([test "x$enable_linux_builtin" != xyes], [
ZFS_LINUX_TEST_RESULT([config_modules], [
AC_MSG_RESULT([yes])
],[
AC_MSG_RESULT([no])
AC_MSG_ERROR([
*** This kernel does not include the required loadable module
*** support!
***
*** To build OpenZFS as a loadable Linux kernel module
*** enable loadable module support by setting
*** `CONFIG_MODULES=y` in the kernel configuration and run
*** `make modules_prepare` in the Linux source tree.
***
*** If you don't intend to enable loadable kernel module
*** support, please compile OpenZFS as a Linux kernel built-in.
***
*** Prepare the Linux source tree by running `make prepare`,
*** use the OpenZFS `--enable-linux-builtin` configure option,
*** copy the OpenZFS sources into the Linux source tree using
*** `./copy-builtin <linux source directory>`,
*** set `CONFIG_ZFS=y` in the kernel configuration and compile
*** kernel as usual.
])
])
], [
ZFS_LINUX_TRY_COMPILE([], [], [
AC_MSG_RESULT([not needed])
],[
AC_MSG_RESULT([error])
AC_MSG_ERROR([
*** This kernel is unable to compile object files.
***
*** Please make sure you prepared the Linux source tree
*** by running `make prepare` there.
])
])
])
])
dnl #
dnl # Check CONFIG_TRIM_UNUSED_KSYMS
dnl #

View File

@ -8,8 +8,8 @@ AC_DEFUN([ZFS_AC_CONFIG_KERNEL], [
ZFS_AC_QAT
dnl # Sanity checks for module building and CONFIG_* defines
ZFS_AC_KERNEL_TEST_MODULE
ZFS_AC_KERNEL_CONFIG_DEFINED
ZFS_AC_MODULE_SYMVERS
dnl # Sequential ZFS_LINUX_TRY_COMPILE tests
ZFS_AC_KERNEL_FPU_HEADER
@ -445,8 +445,6 @@ AC_DEFUN([ZFS_AC_KERNEL], [
AC_SUBST(LINUX)
AC_SUBST(LINUX_OBJ)
AC_SUBST(LINUX_VERSION)
ZFS_AC_MODULE_SYMVERS
])
dnl #
@ -541,27 +539,6 @@ AC_DEFUN([ZFS_AC_QAT], [
])
])
dnl #
dnl # Basic toolchain sanity check.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_TEST_MODULE], [
AC_MSG_CHECKING([whether modules can be built])
ZFS_LINUX_TRY_COMPILE([], [], [
AC_MSG_RESULT([yes])
],[
AC_MSG_RESULT([no])
if test "x$enable_linux_builtin" != xyes; then
AC_MSG_ERROR([
*** Unable to build an empty module.
])
else
AC_MSG_ERROR([
*** Unable to build an empty module.
*** Please run 'make scripts' inside the kernel source tree.])
fi
])
])
dnl #
dnl # ZFS_LINUX_CONFTEST_H
dnl #
@ -664,8 +641,10 @@ AC_DEFUN([ZFS_LINUX_COMPILE], [
build kernel modules with LLVM/CLANG toolchain])
AC_TRY_COMMAND([
KBUILD_MODPOST_NOFINAL="$5" KBUILD_MODPOST_WARN="$6"
make modules -k -j$TEST_JOBS ${KERNEL_CC:+CC=$KERNEL_CC} ${KERNEL_LD:+LD=$KERNEL_LD} ${KERNEL_LLVM:+LLVM=$KERNEL_LLVM} -C $LINUX_OBJ $ARCH_UM
M=$PWD/$1 >$1/build.log 2>&1])
make modules -k -j$TEST_JOBS ${KERNEL_CC:+CC=$KERNEL_CC}
${KERNEL_LD:+LD=$KERNEL_LD} ${KERNEL_LLVM:+LLVM=$KERNEL_LLVM}
CONFIG_MODULES=y CFLAGS_MODULE=-DCONFIG_MODULES
-C $LINUX_OBJ $ARCH_UM M=$PWD/$1 >$1/build.log 2>&1])
AS_IF([AC_TRY_COMMAND([$2])], [$3], [$4])
])