]> granicus.if.org Git - zfs/commitdiff
Split spl-build.m4
authorBrian Behlendorf <behlendorf1@llnl.gov>
Wed, 7 Feb 2018 19:50:24 +0000 (11:50 -0800)
committerGitHub <noreply@github.com>
Wed, 7 Feb 2018 19:50:24 +0000 (11:50 -0800)
Split the kernel interface configure checks in to seperate m4
macro files.  This is intended to facilitate moving the spl
source code in to the zfs repository.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #682

22 files changed:
config/kernel-ctl-table-name.m4 [new file with mode: 0644]
config/kernel-fallocate.m4 [new file with mode: 0644]
config/kernel-group-info.m4 [new file with mode: 0644]
config/kernel-inode-lock.m4 [new file with mode: 0644]
config/kernel-kmem-cache.m4 [new file with mode: 0644]
config/kernel-kuidgid.m4 [new file with mode: 0644]
config/kernel-pde-data.m4 [new file with mode: 0644]
config/kernel-rw.m4 [new file with mode: 0644]
config/kernel-rwsem.m4 [new file with mode: 0644]
config/kernel-sched.m4 [new file with mode: 0644]
config/kernel-set-fs-pwd.m4 [new file with mode: 0644]
config/kernel-shrinker.m4 [new file with mode: 0644]
config/kernel-spinlock.m4 [new file with mode: 0644]
config/kernel-timer.m4 [new file with mode: 0644]
config/kernel-trim-unused-symbols.m4 [new file with mode: 0644]
config/kernel-truncate-range.m4 [new file with mode: 0644]
config/kernel-urange-sleep.m4 [new file with mode: 0644]
config/kernel-vfs-fsync.m4 [new file with mode: 0644]
config/kernel-vfs-getattr.m4 [new file with mode: 0644]
config/kernel-wait.m4 [new file with mode: 0644]
config/kernel-zlib.m4 [new file with mode: 0644]
config/spl-build.m4

diff --git a/config/kernel-ctl-table-name.m4 b/config/kernel-ctl-table-name.m4
new file mode 100644 (file)
index 0000000..8dd2e77
--- /dev/null
@@ -0,0 +1,18 @@
+dnl #
+dnl # 2.6.33 API change,
+dnl # Removed .ctl_name from struct ctl_table.
+dnl #
+AC_DEFUN([SPL_AC_CTL_NAME], [
+       AC_MSG_CHECKING([whether struct ctl_table has ctl_name])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/sysctl.h>
+       ],[
+               struct ctl_table ctl __attribute__ ((unused));
+               ctl.ctl_name = 0;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_CTL_NAME, 1, [struct ctl_table has ctl_name])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-fallocate.m4 b/config/kernel-fallocate.m4
new file mode 100644 (file)
index 0000000..b8c82f4
--- /dev/null
@@ -0,0 +1,68 @@
+dnl #
+dnl # Linux 2.6.38 - 3.x API
+dnl #
+AC_DEFUN([SPL_AC_KERNEL_FILE_FALLOCATE], [
+       AC_MSG_CHECKING([whether fops->fallocate() exists])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               long (*fallocate) (struct file *, int, loff_t, loff_t) = NULL;
+               struct file_operations fops __attribute__ ((unused)) = {
+                       .fallocate = fallocate,
+               };
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_FILE_FALLOCATE, 1, [fops->fallocate() exists])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
+dnl #
+dnl # Linux 2.6.x - 2.6.37 API
+dnl #
+AC_DEFUN([SPL_AC_KERNEL_INODE_FALLOCATE], [
+       AC_MSG_CHECKING([whether iops->fallocate() exists])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               long (*fallocate) (struct inode *, int, loff_t, loff_t) = NULL;
+               struct inode_operations fops __attribute__ ((unused)) = {
+                       .fallocate = fallocate,
+               };
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_INODE_FALLOCATE, 1, [fops->fallocate() exists])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
+
+dnl #
+dnl # PaX Linux 2.6.38 - 3.x API
+dnl #
+AC_DEFUN([SPL_AC_PAX_KERNEL_FILE_FALLOCATE], [
+       AC_MSG_CHECKING([whether fops->fallocate() exists])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               long (*fallocate) (struct file *, int, loff_t, loff_t) = NULL;
+               struct file_operations_no_const fops __attribute__ ((unused)) = {
+                       .fallocate = fallocate,
+               };
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_FILE_FALLOCATE, 1, [fops->fallocate() exists])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
+
+dnl #
+dnl # The fallocate callback was moved from the inode_operations
+dnl # structure to the file_operations structure.
+dnl #
+AC_DEFUN([SPL_AC_KERNEL_FALLOCATE], [
+       SPL_AC_KERNEL_FILE_FALLOCATE
+       SPL_AC_KERNEL_INODE_FALLOCATE
+       SPL_AC_PAX_KERNEL_FILE_FALLOCATE
+])
diff --git a/config/kernel-group-info.m4 b/config/kernel-group-info.m4
new file mode 100644 (file)
index 0000000..4db2bba
--- /dev/null
@@ -0,0 +1,21 @@
+dnl #
+dnl # 4.9 API change
+dnl # group_info changed from 2d array via >blocks to 1d array via ->gid
+dnl #
+AC_DEFUN([SPL_AC_GROUP_INFO_GID], [
+       AC_MSG_CHECKING([whether group_info->gid exists])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/cred.h>
+       ],[
+               struct group_info *gi = groups_alloc(1);
+               gi->gid[0] = KGIDT_INIT(0);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_GROUP_INFO_GID, 1, [group_info->gid exists])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
diff --git a/config/kernel-inode-lock.m4 b/config/kernel-inode-lock.m4
new file mode 100644 (file)
index 0000000..2cc06a5
--- /dev/null
@@ -0,0 +1,23 @@
+dnl #
+dnl # 4.7 API change
+dnl # i_mutex is changed to i_rwsem. Instead of directly using
+dnl # i_mutex/i_rwsem, we should use inode_lock() and inode_lock_shared()
+dnl # We test inode_lock_shared because inode_lock is introduced earlier.
+dnl #
+AC_DEFUN([SPL_AC_INODE_LOCK], [
+       AC_MSG_CHECKING([whether inode_lock_shared() exists])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               struct inode *inode = NULL;
+               inode_lock_shared(inode);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_INODE_LOCK_SHARED, 1, [yes])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
diff --git a/config/kernel-kmem-cache.m4 b/config/kernel-kmem-cache.m4
new file mode 100644 (file)
index 0000000..50a7fdb
--- /dev/null
@@ -0,0 +1,72 @@
+dnl #
+dnl # 2.6.35 API change,
+dnl # The cachep->gfpflags member was renamed cachep->allocflags.  These are
+dnl # private allocation flags which are applied when allocating a new slab
+dnl # in kmem_getpages().  Unfortunately there is no public API for setting
+dnl # non-default flags.
+dnl #
+AC_DEFUN([SPL_AC_KMEM_CACHE_ALLOCFLAGS], [
+       AC_MSG_CHECKING([whether struct kmem_cache has allocflags])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/slab.h>
+       ],[
+               struct kmem_cache cachep __attribute__ ((unused));
+               cachep.allocflags = GFP_KERNEL;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_KMEM_CACHE_ALLOCFLAGS, 1,
+                       [struct kmem_cache has allocflags])
+       ],[
+               AC_MSG_RESULT(no)
+
+               AC_MSG_CHECKING([whether struct kmem_cache has gfpflags])
+               SPL_LINUX_TRY_COMPILE([
+                       #include <linux/slab.h>
+               ],[
+                       struct kmem_cache cachep __attribute__ ((unused));
+                       cachep.gfpflags = GFP_KERNEL;
+               ],[
+                       AC_MSG_RESULT(yes)
+                       AC_DEFINE(HAVE_KMEM_CACHE_GFPFLAGS, 1,
+                               [struct kmem_cache has gfpflags])
+               ],[
+                       AC_MSG_RESULT(no)
+               ])
+       ])
+])
+
+dnl #
+dnl # grsecurity API change,
+dnl # kmem_cache_create() with SLAB_USERCOPY flag replaced by
+dnl # kmem_cache_create_usercopy().
+dnl #
+AC_DEFUN([SPL_AC_KMEM_CACHE_CREATE_USERCOPY], [
+       AC_MSG_CHECKING([whether kmem_cache_create_usercopy() exists])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/slab.h>
+               static void ctor(void *foo)
+               {
+                       // fake ctor
+               }
+       ],[
+               struct kmem_cache *skc_linux_cache;
+               const char *name = "test";
+               size_t size = 4096;
+               size_t align = 8;
+               unsigned long flags = 0;
+               size_t useroffset = 0;
+               size_t usersize = size - useroffset;
+
+               skc_linux_cache = kmem_cache_create_usercopy(
+                       name, size, align, flags, useroffset, usersize, ctor);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_KMEM_CACHE_CREATE_USERCOPY, 1,
+                               [kmem_cache_create_usercopy() exists])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
diff --git a/config/kernel-kuidgid.m4 b/config/kernel-kuidgid.m4
new file mode 100644 (file)
index 0000000..47d1937
--- /dev/null
@@ -0,0 +1,28 @@
+dnl #
+dnl # User namespaces, use kuid_t in place of uid_t
+dnl # where available. Not strictly a user namespaces thing
+dnl # but it should prevent surprises
+dnl #
+AC_DEFUN([SPL_AC_KUIDGID_T], [
+       AC_MSG_CHECKING([whether kuid_t/kgid_t is available])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/uidgid.h>
+       ], [
+               kuid_t userid = KUIDT_INIT(0);
+               kgid_t groupid = KGIDT_INIT(0);
+       ],[
+               SPL_LINUX_TRY_COMPILE([
+                       #include <linux/uidgid.h>
+               ], [
+                       kuid_t userid = 0;
+                       kgid_t groupid = 0;
+               ],[
+                       AC_MSG_RESULT(yes; optional)
+               ],[
+                       AC_MSG_RESULT(yes; mandatory)
+                       AC_DEFINE(HAVE_KUIDGID_T, 1, [kuid_t/kgid_t in use])
+               ])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-pde-data.m4 b/config/kernel-pde-data.m4
new file mode 100644 (file)
index 0000000..6aa5765
--- /dev/null
@@ -0,0 +1,17 @@
+dnl #
+dnl # 3.10 API change,
+dnl # PDE is replaced by PDE_DATA
+dnl #
+AC_DEFUN([SPL_AC_PDE_DATA], [
+       AC_MSG_CHECKING([whether PDE_DATA() is available])
+       SPL_LINUX_TRY_COMPILE_SYMBOL([
+               #include <linux/proc_fs.h>
+       ], [
+               PDE_DATA(NULL);
+       ], [PDE_DATA], [], [
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_PDE_DATA, 1, [yes])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-rw.m4 b/config/kernel-rw.m4
new file mode 100644 (file)
index 0000000..23c14b7
--- /dev/null
@@ -0,0 +1,57 @@
+dnl #
+dnl # 4.14 API change
+dnl # kernel_write() which was introduced in 3.9 was updated to take
+dnl # the offset as a pointer which is needed by vn_rdwr().
+dnl #
+AC_DEFUN([SPL_AC_KERNEL_WRITE], [
+       AC_MSG_CHECKING([whether kernel_write() takes loff_t pointer])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               struct file *file = NULL;
+               const void *buf = NULL;
+               size_t count = 0;
+               loff_t *pos = NULL;
+               ssize_t ret;
+
+               ret = kernel_write(file, buf, count, pos);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_KERNEL_WRITE_PPOS, 1,
+                   [kernel_write() take loff_t pointer])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
+
+dnl #
+dnl # 4.14 API change
+dnl # kernel_read() which has existed for forever was updated to take
+dnl # the offset as a pointer which is needed by vn_rdwr().
+dnl #
+AC_DEFUN([SPL_AC_KERNEL_READ], [
+       AC_MSG_CHECKING([whether kernel_read() takes loff_t pointer])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               struct file *file = NULL;
+               void *buf = NULL;
+               size_t count = 0;
+               loff_t *pos = NULL;
+               ssize_t ret;
+
+               ret = kernel_read(file, buf, count, pos);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_KERNEL_READ_PPOS, 1,
+                   [kernel_read() take loff_t pointer])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
diff --git a/config/kernel-rwsem.m4 b/config/kernel-rwsem.m4
new file mode 100644 (file)
index 0000000..aee20ae
--- /dev/null
@@ -0,0 +1,75 @@
+dnl #
+dnl # 3.1 API Change
+dnl #
+dnl # The rw_semaphore.wait_lock member was changed from spinlock_t to
+dnl # raw_spinlock_t at commit ddb6c9b58a19edcfac93ac670b066c836ff729f1.
+dnl #
+AC_DEFUN([SPL_AC_RWSEM_SPINLOCK_IS_RAW], [
+       AC_MSG_CHECKING([whether struct rw_semaphore member wait_lock is raw])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/rwsem.h>
+       ],[
+               struct rw_semaphore dummy_semaphore __attribute__ ((unused));
+               raw_spinlock_t dummy_lock __attribute__ ((unused)) =
+                   __RAW_SPIN_LOCK_INITIALIZER(dummy_lock);
+               dummy_semaphore.wait_lock = dummy_lock;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(RWSEM_SPINLOCK_IS_RAW, 1,
+               [struct rw_semaphore member wait_lock is raw_spinlock_t])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
+
+dnl #
+dnl # 3.16 API Change
+dnl #
+dnl # rwsem-spinlock "->activity" changed to "->count"
+dnl #
+AC_DEFUN([SPL_AC_RWSEM_ACTIVITY], [
+       AC_MSG_CHECKING([whether struct rw_semaphore has member activity])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/rwsem.h>
+       ],[
+               struct rw_semaphore dummy_semaphore __attribute__ ((unused));
+               dummy_semaphore.activity = 0;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_RWSEM_ACTIVITY, 1,
+               [struct rw_semaphore has member activity])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
+
+dnl #
+dnl # 4.8 API Change
+dnl #
+dnl # rwsem "->count" changed to atomic_long_t type
+dnl #
+AC_DEFUN([SPL_AC_RWSEM_ATOMIC_LONG_COUNT], [
+       AC_MSG_CHECKING(
+       [whether struct rw_semaphore has atomic_long_t member count])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/rwsem.h>
+       ],[
+               DECLARE_RWSEM(dummy_semaphore);
+               (void) atomic_long_read(&dummy_semaphore.count);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_RWSEM_ATOMIC_LONG_COUNT, 1,
+               [struct rw_semaphore has atomic_long_t member count])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
diff --git a/config/kernel-sched.m4 b/config/kernel-sched.m4
new file mode 100644 (file)
index 0000000..5ae2167
--- /dev/null
@@ -0,0 +1,56 @@
+dnl #
+dnl # 3.9 API change,
+dnl # Moved things from linux/sched.h to linux/sched/rt.h
+dnl #
+AC_DEFUN([SPL_AC_SCHED_RT_HEADER],
+       [AC_MSG_CHECKING([whether header linux/sched/rt.h exists])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/sched.h>
+               #include <linux/sched/rt.h>
+       ],[
+               return 0;
+       ],[
+               AC_DEFINE(HAVE_SCHED_RT_HEADER, 1, [linux/sched/rt.h exists])
+               AC_MSG_RESULT(yes)
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
+
+dnl #
+dnl # 4.11 API change,
+dnl # Moved things from linux/sched.h to linux/sched/signal.h
+dnl #
+AC_DEFUN([SPL_AC_SCHED_SIGNAL_HEADER],
+       [AC_MSG_CHECKING([whether header linux/sched/signal.h exists])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/sched.h>
+               #include <linux/sched/signal.h>
+       ],[
+               return 0;
+       ],[
+               AC_DEFINE(HAVE_SCHED_SIGNAL_HEADER, 1, [linux/sched/signal.h exists])
+               AC_MSG_RESULT(yes)
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
+dnl #
+dnl # 3.19 API change
+dnl # The io_schedule_timeout() function is present in all 2.6.32 kernels
+dnl # but it was not exported until Linux 3.19.  The RHEL 7.x kernels which
+dnl # are based on a 3.10 kernel do export this symbol.
+dnl #
+AC_DEFUN([SPL_AC_IO_SCHEDULE_TIMEOUT], [
+       AC_MSG_CHECKING([whether io_schedule_timeout() is available])
+       SPL_LINUX_TRY_COMPILE_SYMBOL([
+               #include <linux/sched.h>
+       ], [
+               (void) io_schedule_timeout(1);
+       ], [io_schedule_timeout], [], [
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_IO_SCHEDULE_TIMEOUT, 1, [yes])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-set-fs-pwd.m4 b/config/kernel-set-fs-pwd.m4
new file mode 100644 (file)
index 0000000..849e7e6
--- /dev/null
@@ -0,0 +1,39 @@
+dnl #
+dnl # 3.9 API change
+dnl # set_fs_pwd takes const struct path *
+dnl #
+AC_DEFUN([SPL_AC_SET_FS_PWD_WITH_CONST],
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       [AC_MSG_CHECKING([whether set_fs_pwd() requires const struct path *])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/spinlock.h>
+               #include <linux/fs_struct.h>
+               #include <linux/path.h>
+               void (*const set_fs_pwd_func)
+                       (struct fs_struct *, const struct path *)
+                       = set_fs_pwd;
+       ],[
+               return 0;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_SET_FS_PWD_WITH_CONST, 1,
+                       [set_fs_pwd() needs const path *])
+       ],[
+               SPL_LINUX_TRY_COMPILE([
+                       #include <linux/spinlock.h>
+                       #include <linux/fs_struct.h>
+                       #include <linux/path.h>
+                       void (*const set_fs_pwd_func)
+                               (struct fs_struct *, struct path *)
+                               = set_fs_pwd;
+               ],[
+                       return 0;
+               ],[
+                       AC_MSG_RESULT(no)
+               ],[
+                       AC_MSG_ERROR(unknown)
+               ])
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
diff --git a/config/kernel-shrinker.m4 b/config/kernel-shrinker.m4
new file mode 100644 (file)
index 0000000..6fc9b54
--- /dev/null
@@ -0,0 +1,125 @@
+AC_DEFUN([SPL_AC_SHRINKER_CALLBACK],[
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       dnl #
+       dnl # 2.6.23 to 2.6.34 API change
+       dnl # ->shrink(int nr_to_scan, gfp_t gfp_mask)
+       dnl #
+       AC_MSG_CHECKING([whether old 2-argument shrinker exists])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/mm.h>
+
+               int shrinker_cb(int nr_to_scan, gfp_t gfp_mask);
+       ],[
+               struct shrinker cache_shrinker = {
+                       .shrink = shrinker_cb,
+                       .seeks = DEFAULT_SEEKS,
+               };
+               register_shrinker(&cache_shrinker);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_2ARGS_OLD_SHRINKER_CALLBACK, 1,
+                       [old shrinker callback wants 2 args])
+       ],[
+               AC_MSG_RESULT(no)
+               dnl #
+               dnl # 2.6.35 - 2.6.39 API change
+               dnl # ->shrink(struct shrinker *,
+               dnl #          int nr_to_scan, gfp_t gfp_mask)
+               dnl #
+               AC_MSG_CHECKING([whether old 3-argument shrinker exists])
+               SPL_LINUX_TRY_COMPILE([
+                       #include <linux/mm.h>
+
+                       int shrinker_cb(struct shrinker *, int nr_to_scan,
+                                       gfp_t gfp_mask);
+               ],[
+                       struct shrinker cache_shrinker = {
+                               .shrink = shrinker_cb,
+                               .seeks = DEFAULT_SEEKS,
+                       };
+                       register_shrinker(&cache_shrinker);
+               ],[
+                       AC_MSG_RESULT(yes)
+                       AC_DEFINE(HAVE_3ARGS_SHRINKER_CALLBACK, 1,
+                               [old shrinker callback wants 3 args])
+               ],[
+                       AC_MSG_RESULT(no)
+                       dnl #
+                       dnl # 3.0 - 3.11 API change
+                       dnl # ->shrink(struct shrinker *,
+                       dnl #          struct shrink_control *sc)
+                       dnl #
+                       AC_MSG_CHECKING(
+                               [whether new 2-argument shrinker exists])
+                       SPL_LINUX_TRY_COMPILE([
+                               #include <linux/mm.h>
+
+                               int shrinker_cb(struct shrinker *,
+                                               struct shrink_control *sc);
+                       ],[
+                               struct shrinker cache_shrinker = {
+                                       .shrink = shrinker_cb,
+                                       .seeks = DEFAULT_SEEKS,
+                               };
+                               register_shrinker(&cache_shrinker);
+                       ],[
+                               AC_MSG_RESULT(yes)
+                               AC_DEFINE(HAVE_2ARGS_NEW_SHRINKER_CALLBACK, 1,
+                                       [new shrinker callback wants 2 args])
+                       ],[
+                               AC_MSG_RESULT(no)
+                               dnl #
+                               dnl # 3.12 API change,
+                               dnl # ->shrink() is logically split in to
+                               dnl # ->count_objects() and ->scan_objects()
+                               dnl #
+                               AC_MSG_CHECKING(
+                                   [whether ->count_objects callback exists])
+                               SPL_LINUX_TRY_COMPILE([
+                                       #include <linux/mm.h>
+
+                                       unsigned long shrinker_cb(
+                                               struct shrinker *,
+                                               struct shrink_control *sc);
+                               ],[
+                                       struct shrinker cache_shrinker = {
+                                               .count_objects = shrinker_cb,
+                                               .scan_objects = shrinker_cb,
+                                               .seeks = DEFAULT_SEEKS,
+                                       };
+                                       register_shrinker(&cache_shrinker);
+                               ],[
+                                       AC_MSG_RESULT(yes)
+                                       AC_DEFINE(HAVE_SPLIT_SHRINKER_CALLBACK,
+                                               1, [->count_objects exists])
+                               ],[
+                                       AC_MSG_ERROR(error)
+                               ])
+                       ])
+               ])
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
+
+dnl #
+dnl # 2.6.39 API change,
+dnl # Shrinker adjust to use common shrink_control structure.
+dnl #
+AC_DEFUN([SPL_AC_SHRINK_CONTROL_STRUCT], [
+       AC_MSG_CHECKING([whether struct shrink_control exists])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/mm.h>
+       ],[
+               struct shrink_control sc __attribute__ ((unused));
+
+               sc.nr_to_scan = 0;
+               sc.gfp_mask = GFP_KERNEL;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_SHRINK_CONTROL_STRUCT, 1,
+                       [struct shrink_control exists])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-spinlock.m4 b/config/kernel-spinlock.m4
new file mode 100644 (file)
index 0000000..136262d
--- /dev/null
@@ -0,0 +1,24 @@
+dnl #
+dnl # 2.6.36 API change,
+dnl # The 'struct fs_struct->lock' was changed from a rwlock_t to
+dnl # a spinlock_t to improve the fastpath performance.
+dnl #
+AC_DEFUN([SPL_AC_FS_STRUCT_SPINLOCK], [
+       AC_MSG_CHECKING([whether struct fs_struct uses spinlock_t])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/sched.h>
+               #include <linux/fs_struct.h>
+       ],[
+               static struct fs_struct fs;
+               spin_lock_init(&fs.lock);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_FS_STRUCT_SPINLOCK, 1,
+                         [struct fs_struct uses spinlock_t])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
diff --git a/config/kernel-timer.m4 b/config/kernel-timer.m4
new file mode 100644 (file)
index 0000000..93b5158
--- /dev/null
@@ -0,0 +1,32 @@
+dnl #
+dnl # 4.15 API change
+dnl # https://lkml.org/lkml/2017/11/25/90
+dnl # Check if timer_list.func get passed a timer_list or an unsigned long
+dnl # (older kernels).  Also sanity check the from_timer() and timer_setup()
+dnl # macros are available as well, since they will be used in the same newer
+dnl # kernels that support the new timer_list.func signature.
+dnl #
+AC_DEFUN([SPL_AC_KERNEL_TIMER_FUNCTION_TIMER_LIST], [
+       AC_MSG_CHECKING([whether timer_list.function gets a timer_list])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/timer.h>
+               void task_expire(struct timer_list *tl) {}
+       ],[
+               #ifndef from_timer
+               #error "No from_timer() macro"
+               #endif
+
+               struct timer_list timer;
+               timer.function = task_expire;
+               timer_setup(&timer, NULL, 0);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_KERNEL_TIMER_FUNCTION_TIMER_LIST, 1,
+                   [timer_list.function gets a timer_list])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
diff --git a/config/kernel-trim-unused-symbols.m4 b/config/kernel-trim-unused-symbols.m4
new file mode 100644 (file)
index 0000000..d1ac2f3
--- /dev/null
@@ -0,0 +1,19 @@
+dnl #
+dnl # config trim unused symbols,
+dnl # Verify the kernel has CONFIG_TRIM_UNUSED_KSYMS DISABLED.
+dnl #
+AC_DEFUN([SPL_AC_CONFIG_TRIM_UNUSED_KSYMS], [
+       AC_MSG_CHECKING([whether CONFIG_TRIM_UNUSED_KSYM is disabled])
+       SPL_LINUX_TRY_COMPILE([
+               #if defined(CONFIG_TRIM_UNUSED_KSYMS)
+               #error CONFIG_TRIM_UNUSED_KSYMS not defined
+               #endif
+       ],[ ],[
+               AC_MSG_RESULT([yes])
+       ],[
+               AC_MSG_RESULT([no])
+               AC_MSG_ERROR([
+       *** This kernel has unused symbols trimming enabled, please disable.
+       *** Rebuild the kernel with CONFIG_TRIM_UNUSED_KSYMS=n set.])
+       ])
+])
diff --git a/config/kernel-truncate-range.m4 b/config/kernel-truncate-range.m4
new file mode 100644 (file)
index 0000000..4b1600b
--- /dev/null
@@ -0,0 +1,19 @@
+dnl #
+dnl # 3.5 API change,
+dnl # inode_operations.truncate_range removed
+dnl #
+AC_DEFUN([SPL_AC_INODE_TRUNCATE_RANGE], [
+       AC_MSG_CHECKING([whether truncate_range() inode operation is available])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               struct inode_operations ops;
+               ops.truncate_range = NULL;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_INODE_TRUNCATE_RANGE, 1,
+                       [truncate_range() inode operation is available])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-urange-sleep.m4 b/config/kernel-urange-sleep.m4
new file mode 100644 (file)
index 0000000..85beca6
--- /dev/null
@@ -0,0 +1,21 @@
+dnl #
+dnl # 2.6.36 API compatibility.
+dnl # Added usleep_range timer.
+dnl # usleep_range is a finer precision implementation of msleep
+dnl # designed to be a drop-in replacement for udelay where a precise
+dnl # sleep / busy-wait is unnecessary.
+dnl #
+AC_DEFUN([SPL_AC_USLEEP_RANGE], [
+       AC_MSG_CHECKING([whether usleep_range() is available])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/delay.h>
+       ],[
+               usleep_range(0, 0);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_USLEEP_RANGE, 1,
+                         [usleep_range is available])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-vfs-fsync.m4 b/config/kernel-vfs-fsync.m4
new file mode 100644 (file)
index 0000000..3c42bf1
--- /dev/null
@@ -0,0 +1,17 @@
+dnl #
+dnl # 2.6.35 API change,
+dnl # Unused 'struct dentry *' removed from vfs_fsync() prototype.
+dnl #
+AC_DEFUN([SPL_AC_2ARGS_VFS_FSYNC], [
+       AC_MSG_CHECKING([whether vfs_fsync() wants 2 args])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               vfs_fsync(NULL, 0);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_2ARGS_VFS_FSYNC, 1, [vfs_fsync() wants 2 args])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-vfs-getattr.m4 b/config/kernel-vfs-getattr.m4
new file mode 100644 (file)
index 0000000..7772cb5
--- /dev/null
@@ -0,0 +1,62 @@
+dnl #
+dnl # 4.11 API, a528d35e@torvalds/linux
+dnl # vfs_getattr(const struct path *p, struct kstat *s, u32 m, unsigned int f)
+dnl #
+AC_DEFUN([SPL_AC_4ARGS_VFS_GETATTR], [
+       AC_MSG_CHECKING([whether vfs_getattr() wants 4 args])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               vfs_getattr((const struct path *)NULL,
+                       (struct kstat *)NULL,
+                       (u32)0,
+                       (unsigned int)0);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_4ARGS_VFS_GETATTR, 1,
+                 [vfs_getattr wants 4 args])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
+
+dnl #
+dnl # 3.9 API
+dnl # vfs_getattr(struct path *p, struct kstat *s)
+dnl #
+AC_DEFUN([SPL_AC_2ARGS_VFS_GETATTR], [
+       AC_MSG_CHECKING([whether vfs_getattr() wants 2 args])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               vfs_getattr((struct path *) NULL,
+                       (struct kstat *)NULL);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_2ARGS_VFS_GETATTR, 1,
+                         [vfs_getattr wants 2 args])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
+
+dnl #
+dnl # <3.9 API
+dnl # vfs_getattr(struct vfsmount *v, struct dentry *d, struct kstat *k)
+dnl #
+AC_DEFUN([SPL_AC_3ARGS_VFS_GETATTR], [
+       AC_MSG_CHECKING([whether vfs_getattr() wants 3 args])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/fs.h>
+       ],[
+               vfs_getattr((struct vfsmount *)NULL,
+                       (struct dentry *)NULL,
+                       (struct kstat *)NULL);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_3ARGS_VFS_GETATTR, 1,
+                 [vfs_getattr wants 3 args])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-wait.m4 b/config/kernel-wait.m4
new file mode 100644 (file)
index 0000000..5f718a1
--- /dev/null
@@ -0,0 +1,76 @@
+dnl #
+dnl # 3.17 API change,
+dnl # wait_on_bit() no longer requires an action argument. The former
+dnl # "wait_on_bit" interface required an 'action' function to be provided
+dnl # which does the actual waiting. There were over 20 such functions in the
+dnl # kernel, many of them identical, though most cases can be satisfied by one
+dnl # of just two functions: one which uses io_schedule() and one which just
+dnl # uses schedule().  This API change was made to consolidate all of those
+dnl # redundant wait functions.
+dnl #
+AC_DEFUN([SPL_AC_WAIT_ON_BIT], [
+       AC_MSG_CHECKING([whether wait_on_bit() takes an action])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/wait.h>
+       ],[
+               int (*action)(void *) = NULL;
+               wait_on_bit(NULL, 0, action, 0);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_WAIT_ON_BIT_ACTION, 1, [yes])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
+dnl #
+dnl # 4.13 API change
+dnl # Renamed struct wait_queue -> struct wait_queue_entry.
+dnl #
+AC_DEFUN([SPL_AC_WAIT_QUEUE_ENTRY_T], [
+       AC_MSG_CHECKING([whether wait_queue_entry_t exists])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/wait.h>
+       ],[
+               wait_queue_entry_t *entry __attribute__ ((unused));
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_WAIT_QUEUE_ENTRY_T, 1,
+                   [wait_queue_entry_t exists])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
+
+dnl #
+dnl # 4.13 API change
+dnl # Renamed wait_queue_head::task_list -> wait_queue_head::head
+dnl # Renamed wait_queue_entry::task_list -> wait_queue_entry::entry
+dnl #
+AC_DEFUN([SPL_AC_WAIT_QUEUE_HEAD_ENTRY], [
+       AC_MSG_CHECKING([whether wq_head->head and wq_entry->entry exist])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/wait.h>
+
+               #ifdef HAVE_WAIT_QUEUE_ENTRY_T
+               typedef wait_queue_head_t       spl_wait_queue_head_t;
+               typedef wait_queue_entry_t      spl_wait_queue_entry_t;
+               #else
+               typedef wait_queue_head_t       spl_wait_queue_head_t;
+               typedef wait_queue_t            spl_wait_queue_entry_t;
+               #endif
+       ],[
+               spl_wait_queue_head_t wq_head;
+               spl_wait_queue_entry_t wq_entry;
+               struct list_head *head __attribute__ ((unused));
+               struct list_head *entry __attribute__ ((unused));
+
+               head = &wq_head.head;
+               entry = &wq_entry.entry;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_WAIT_QUEUE_HEAD_ENTRY, 1,
+                   [wq_head->head and wq_entry->entry exist])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
diff --git a/config/kernel-zlib.m4 b/config/kernel-zlib.m4
new file mode 100644 (file)
index 0000000..bb23646
--- /dev/null
@@ -0,0 +1,63 @@
+dnl #
+dnl # zlib inflate compat,
+dnl # Verify the kernel has CONFIG_ZLIB_INFLATE support enabled.
+dnl #
+AC_DEFUN([SPL_AC_CONFIG_ZLIB_INFLATE], [
+       AC_MSG_CHECKING([whether CONFIG_ZLIB_INFLATE is defined])
+       SPL_LINUX_TRY_COMPILE([
+               #if !defined(CONFIG_ZLIB_INFLATE) && \
+                   !defined(CONFIG_ZLIB_INFLATE_MODULE)
+               #error CONFIG_ZLIB_INFLATE not defined
+               #endif
+       ],[ ],[
+               AC_MSG_RESULT([yes])
+       ],[
+               AC_MSG_RESULT([no])
+               AC_MSG_ERROR([
+       *** This kernel does not include the required zlib inflate support.
+       *** Rebuild the kernel with CONFIG_ZLIB_INFLATE=y|m set.])
+       ])
+])
+
+dnl #
+dnl # zlib deflate compat,
+dnl # Verify the kernel has CONFIG_ZLIB_DEFLATE support enabled.
+dnl #
+AC_DEFUN([SPL_AC_CONFIG_ZLIB_DEFLATE], [
+       AC_MSG_CHECKING([whether CONFIG_ZLIB_DEFLATE is defined])
+       SPL_LINUX_TRY_COMPILE([
+               #if !defined(CONFIG_ZLIB_DEFLATE) && \
+                   !defined(CONFIG_ZLIB_DEFLATE_MODULE)
+               #error CONFIG_ZLIB_DEFLATE not defined
+               #endif
+       ],[ ],[
+               AC_MSG_RESULT([yes])
+       ],[
+               AC_MSG_RESULT([no])
+               AC_MSG_ERROR([
+       *** This kernel does not include the required zlib deflate support.
+       *** Rebuild the kernel with CONFIG_ZLIB_DEFLATE=y|m set.])
+       ])
+])
+
+dnl #
+dnl # 2.6.39 API compat,
+dnl # The function zlib_deflate_workspacesize() now take 2 arguments.
+dnl # This was done to avoid always having to allocate the maximum size
+dnl # workspace (268K).  The caller can now specific the windowBits and
+dnl # memLevel compression parameters to get a smaller workspace.
+dnl #
+AC_DEFUN([SPL_AC_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE],
+       [AC_MSG_CHECKING([whether zlib_deflate_workspacesize() wants 2 args])
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/zlib.h>
+       ],[
+               return zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE, 1,
+                         [zlib_deflate_workspacesize() wants 2 args])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+])
index afc8de65fa241deb2f3b08da5fd9a99e8587c0d0..553b5d51b67b9539b21274f9c5b934e218cfdb80 100644 (file)
@@ -753,959 +753,3 @@ AC_DEFUN([SPL_AC_ATOMIC_SPINLOCK], [
        AC_MSG_CHECKING([whether kernel defines atomic64_t])
        AC_MSG_RESULT([$have_atomic64_t])
 ])
-
-AC_DEFUN([SPL_AC_SHRINKER_CALLBACK],[
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       dnl #
-       dnl # 2.6.23 to 2.6.34 API change
-       dnl # ->shrink(int nr_to_scan, gfp_t gfp_mask)
-       dnl #
-       AC_MSG_CHECKING([whether old 2-argument shrinker exists])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/mm.h>
-
-               int shrinker_cb(int nr_to_scan, gfp_t gfp_mask);
-       ],[
-               struct shrinker cache_shrinker = {
-                       .shrink = shrinker_cb,
-                       .seeks = DEFAULT_SEEKS,
-               };
-               register_shrinker(&cache_shrinker);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_2ARGS_OLD_SHRINKER_CALLBACK, 1,
-                       [old shrinker callback wants 2 args])
-       ],[
-               AC_MSG_RESULT(no)
-               dnl #
-               dnl # 2.6.35 - 2.6.39 API change
-               dnl # ->shrink(struct shrinker *,
-               dnl #          int nr_to_scan, gfp_t gfp_mask)
-               dnl #
-               AC_MSG_CHECKING([whether old 3-argument shrinker exists])
-               SPL_LINUX_TRY_COMPILE([
-                       #include <linux/mm.h>
-
-                       int shrinker_cb(struct shrinker *, int nr_to_scan,
-                                       gfp_t gfp_mask);
-               ],[
-                       struct shrinker cache_shrinker = {
-                               .shrink = shrinker_cb,
-                               .seeks = DEFAULT_SEEKS,
-                       };
-                       register_shrinker(&cache_shrinker);
-               ],[
-                       AC_MSG_RESULT(yes)
-                       AC_DEFINE(HAVE_3ARGS_SHRINKER_CALLBACK, 1,
-                               [old shrinker callback wants 3 args])
-               ],[
-                       AC_MSG_RESULT(no)
-                       dnl #
-                       dnl # 3.0 - 3.11 API change
-                       dnl # ->shrink(struct shrinker *,
-                       dnl #          struct shrink_control *sc)
-                       dnl #
-                       AC_MSG_CHECKING(
-                               [whether new 2-argument shrinker exists])
-                       SPL_LINUX_TRY_COMPILE([
-                               #include <linux/mm.h>
-
-                               int shrinker_cb(struct shrinker *,
-                                               struct shrink_control *sc);
-                       ],[
-                               struct shrinker cache_shrinker = {
-                                       .shrink = shrinker_cb,
-                                       .seeks = DEFAULT_SEEKS,
-                               };
-                               register_shrinker(&cache_shrinker);
-                       ],[
-                               AC_MSG_RESULT(yes)
-                               AC_DEFINE(HAVE_2ARGS_NEW_SHRINKER_CALLBACK, 1,
-                                       [new shrinker callback wants 2 args])
-                       ],[
-                               AC_MSG_RESULT(no)
-                               dnl #
-                               dnl # 3.12 API change,
-                               dnl # ->shrink() is logically split in to
-                               dnl # ->count_objects() and ->scan_objects()
-                               dnl #
-                               AC_MSG_CHECKING(
-                                   [whether ->count_objects callback exists])
-                               SPL_LINUX_TRY_COMPILE([
-                                       #include <linux/mm.h>
-
-                                       unsigned long shrinker_cb(
-                                               struct shrinker *,
-                                               struct shrink_control *sc);
-                               ],[
-                                       struct shrinker cache_shrinker = {
-                                               .count_objects = shrinker_cb,
-                                               .scan_objects = shrinker_cb,
-                                               .seeks = DEFAULT_SEEKS,
-                                       };
-                                       register_shrinker(&cache_shrinker);
-                               ],[
-                                       AC_MSG_RESULT(yes)
-                                       AC_DEFINE(HAVE_SPLIT_SHRINKER_CALLBACK,
-                                               1, [->count_objects exists])
-                               ],[
-                                       AC_MSG_ERROR(error)
-                               ])
-                       ])
-               ])
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # 2.6.33 API change,
-dnl # Removed .ctl_name from struct ctl_table.
-dnl #
-AC_DEFUN([SPL_AC_CTL_NAME], [
-       AC_MSG_CHECKING([whether struct ctl_table has ctl_name])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/sysctl.h>
-       ],[
-               struct ctl_table ctl __attribute__ ((unused));
-               ctl.ctl_name = 0;
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_CTL_NAME, 1, [struct ctl_table has ctl_name])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 3.10 API change,
-dnl # PDE is replaced by PDE_DATA
-dnl #
-AC_DEFUN([SPL_AC_PDE_DATA], [
-       AC_MSG_CHECKING([whether PDE_DATA() is available])
-       SPL_LINUX_TRY_COMPILE_SYMBOL([
-               #include <linux/proc_fs.h>
-       ], [
-               PDE_DATA(NULL);
-       ], [PDE_DATA], [], [
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_PDE_DATA, 1, [yes])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 3.9 API change
-dnl # set_fs_pwd takes const struct path *
-dnl #
-AC_DEFUN([SPL_AC_SET_FS_PWD_WITH_CONST],
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       [AC_MSG_CHECKING([whether set_fs_pwd() requires const struct path *])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/spinlock.h>
-               #include <linux/fs_struct.h>
-               #include <linux/path.h>
-               void (*const set_fs_pwd_func)
-                       (struct fs_struct *, const struct path *)
-                       = set_fs_pwd;
-       ],[
-               return 0;
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_SET_FS_PWD_WITH_CONST, 1,
-                       [set_fs_pwd() needs const path *])
-       ],[
-               SPL_LINUX_TRY_COMPILE([
-                       #include <linux/spinlock.h>
-                       #include <linux/fs_struct.h>
-                       #include <linux/path.h>
-                       void (*const set_fs_pwd_func)
-                               (struct fs_struct *, struct path *)
-                               = set_fs_pwd;
-               ],[
-                       return 0;
-               ],[
-                       AC_MSG_RESULT(no)
-               ],[
-                       AC_MSG_ERROR(unknown)
-               ])
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # 2.6.36 API change,
-dnl # The 'struct fs_struct->lock' was changed from a rwlock_t to
-dnl # a spinlock_t to improve the fastpath performance.
-dnl #
-AC_DEFUN([SPL_AC_FS_STRUCT_SPINLOCK], [
-       AC_MSG_CHECKING([whether struct fs_struct uses spinlock_t])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/sched.h>
-               #include <linux/fs_struct.h>
-       ],[
-               static struct fs_struct fs;
-               spin_lock_init(&fs.lock);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_FS_STRUCT_SPINLOCK, 1,
-                         [struct fs_struct uses spinlock_t])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # User namespaces, use kuid_t in place of uid_t
-dnl # where available. Not strictly a user namespaces thing
-dnl # but it should prevent surprises
-dnl #
-AC_DEFUN([SPL_AC_KUIDGID_T], [
-       AC_MSG_CHECKING([whether kuid_t/kgid_t is available])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/uidgid.h>
-       ], [
-               kuid_t userid = KUIDT_INIT(0);
-               kgid_t groupid = KGIDT_INIT(0);
-       ],[
-               SPL_LINUX_TRY_COMPILE([
-                       #include <linux/uidgid.h>
-               ], [
-                       kuid_t userid = 0;
-                       kgid_t groupid = 0;
-               ],[
-                       AC_MSG_RESULT(yes; optional)
-               ],[
-                       AC_MSG_RESULT(yes; mandatory)
-                       AC_DEFINE(HAVE_KUIDGID_T, 1, [kuid_t/kgid_t in use])
-               ])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 2.6.35 API change,
-dnl # Unused 'struct dentry *' removed from vfs_fsync() prototype.
-dnl #
-AC_DEFUN([SPL_AC_2ARGS_VFS_FSYNC], [
-       AC_MSG_CHECKING([whether vfs_fsync() wants 2 args])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               vfs_fsync(NULL, 0);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_2ARGS_VFS_FSYNC, 1, [vfs_fsync() wants 2 args])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 3.5 API change,
-dnl # inode_operations.truncate_range removed
-dnl #
-AC_DEFUN([SPL_AC_INODE_TRUNCATE_RANGE], [
-       AC_MSG_CHECKING([whether truncate_range() inode operation is available])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               struct inode_operations ops;
-               ops.truncate_range = NULL;
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_INODE_TRUNCATE_RANGE, 1,
-                       [truncate_range() inode operation is available])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # Linux 2.6.38 - 3.x API
-dnl #
-AC_DEFUN([SPL_AC_KERNEL_FILE_FALLOCATE], [
-       AC_MSG_CHECKING([whether fops->fallocate() exists])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               long (*fallocate) (struct file *, int, loff_t, loff_t) = NULL;
-               struct file_operations fops __attribute__ ((unused)) = {
-                       .fallocate = fallocate,
-               };
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_FILE_FALLOCATE, 1, [fops->fallocate() exists])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # Linux 2.6.x - 2.6.37 API
-dnl #
-AC_DEFUN([SPL_AC_KERNEL_INODE_FALLOCATE], [
-       AC_MSG_CHECKING([whether iops->fallocate() exists])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               long (*fallocate) (struct inode *, int, loff_t, loff_t) = NULL;
-               struct inode_operations fops __attribute__ ((unused)) = {
-                       .fallocate = fallocate,
-               };
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_INODE_FALLOCATE, 1, [fops->fallocate() exists])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # PaX Linux 2.6.38 - 3.x API
-dnl #
-AC_DEFUN([SPL_AC_PAX_KERNEL_FILE_FALLOCATE], [
-       AC_MSG_CHECKING([whether fops->fallocate() exists])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               long (*fallocate) (struct file *, int, loff_t, loff_t) = NULL;
-               struct file_operations_no_const fops __attribute__ ((unused)) = {
-                       .fallocate = fallocate,
-               };
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_FILE_FALLOCATE, 1, [fops->fallocate() exists])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # The fallocate callback was moved from the inode_operations
-dnl # structure to the file_operations structure.
-dnl #
-AC_DEFUN([SPL_AC_KERNEL_FALLOCATE], [
-       SPL_AC_KERNEL_FILE_FALLOCATE
-       SPL_AC_KERNEL_INODE_FALLOCATE
-       SPL_AC_PAX_KERNEL_FILE_FALLOCATE
-])
-
-dnl #
-dnl # zlib inflate compat,
-dnl # Verify the kernel has CONFIG_ZLIB_INFLATE support enabled.
-dnl #
-AC_DEFUN([SPL_AC_CONFIG_ZLIB_INFLATE], [
-       AC_MSG_CHECKING([whether CONFIG_ZLIB_INFLATE is defined])
-       SPL_LINUX_TRY_COMPILE([
-               #if !defined(CONFIG_ZLIB_INFLATE) && \
-                   !defined(CONFIG_ZLIB_INFLATE_MODULE)
-               #error CONFIG_ZLIB_INFLATE not defined
-               #endif
-       ],[ ],[
-               AC_MSG_RESULT([yes])
-       ],[
-               AC_MSG_RESULT([no])
-               AC_MSG_ERROR([
-       *** This kernel does not include the required zlib inflate support.
-       *** Rebuild the kernel with CONFIG_ZLIB_INFLATE=y|m set.])
-       ])
-])
-
-dnl #
-dnl # zlib deflate compat,
-dnl # Verify the kernel has CONFIG_ZLIB_DEFLATE support enabled.
-dnl #
-AC_DEFUN([SPL_AC_CONFIG_ZLIB_DEFLATE], [
-       AC_MSG_CHECKING([whether CONFIG_ZLIB_DEFLATE is defined])
-       SPL_LINUX_TRY_COMPILE([
-               #if !defined(CONFIG_ZLIB_DEFLATE) && \
-                   !defined(CONFIG_ZLIB_DEFLATE_MODULE)
-               #error CONFIG_ZLIB_DEFLATE not defined
-               #endif
-       ],[ ],[
-               AC_MSG_RESULT([yes])
-       ],[
-               AC_MSG_RESULT([no])
-               AC_MSG_ERROR([
-       *** This kernel does not include the required zlib deflate support.
-       *** Rebuild the kernel with CONFIG_ZLIB_DEFLATE=y|m set.])
-       ])
-])
-
-dnl #
-dnl # config trim unused symbols,
-dnl # Verify the kernel has CONFIG_TRIM_UNUSED_KSYMS DISABLED.
-dnl #
-AC_DEFUN([SPL_AC_CONFIG_TRIM_UNUSED_KSYMS], [
-       AC_MSG_CHECKING([whether CONFIG_TRIM_UNUSED_KSYM is disabled])
-       SPL_LINUX_TRY_COMPILE([
-               #if defined(CONFIG_TRIM_UNUSED_KSYMS)
-               #error CONFIG_TRIM_UNUSED_KSYMS not defined
-               #endif
-       ],[ ],[
-               AC_MSG_RESULT([yes])
-       ],[
-               AC_MSG_RESULT([no])
-               AC_MSG_ERROR([
-       *** This kernel has unused symbols trimming enabled, please disable.
-       *** Rebuild the kernel with CONFIG_TRIM_UNUSED_KSYMS=n set.])
-       ])
-])
-
-dnl #
-dnl # 2.6.39 API compat,
-dnl # The function zlib_deflate_workspacesize() now take 2 arguments.
-dnl # This was done to avoid always having to allocate the maximum size
-dnl # workspace (268K).  The caller can now specific the windowBits and
-dnl # memLevel compression parameters to get a smaller workspace.
-dnl #
-AC_DEFUN([SPL_AC_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE],
-       [AC_MSG_CHECKING([whether zlib_deflate_workspacesize() wants 2 args])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/zlib.h>
-       ],[
-               return zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE, 1,
-                         [zlib_deflate_workspacesize() wants 2 args])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 2.6.39 API change,
-dnl # Shrinker adjust to use common shrink_control structure.
-dnl #
-AC_DEFUN([SPL_AC_SHRINK_CONTROL_STRUCT], [
-       AC_MSG_CHECKING([whether struct shrink_control exists])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/mm.h>
-       ],[
-               struct shrink_control sc __attribute__ ((unused));
-
-               sc.nr_to_scan = 0;
-               sc.gfp_mask = GFP_KERNEL;
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_SHRINK_CONTROL_STRUCT, 1,
-                       [struct shrink_control exists])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 3.1 API Change
-dnl #
-dnl # The rw_semaphore.wait_lock member was changed from spinlock_t to
-dnl # raw_spinlock_t at commit ddb6c9b58a19edcfac93ac670b066c836ff729f1.
-dnl #
-AC_DEFUN([SPL_AC_RWSEM_SPINLOCK_IS_RAW], [
-       AC_MSG_CHECKING([whether struct rw_semaphore member wait_lock is raw])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/rwsem.h>
-       ],[
-               struct rw_semaphore dummy_semaphore __attribute__ ((unused));
-               raw_spinlock_t dummy_lock __attribute__ ((unused)) =
-                   __RAW_SPIN_LOCK_INITIALIZER(dummy_lock);
-               dummy_semaphore.wait_lock = dummy_lock;
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(RWSEM_SPINLOCK_IS_RAW, 1,
-               [struct rw_semaphore member wait_lock is raw_spinlock_t])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # 3.16 API Change
-dnl #
-dnl # rwsem-spinlock "->activity" changed to "->count"
-dnl #
-AC_DEFUN([SPL_AC_RWSEM_ACTIVITY], [
-       AC_MSG_CHECKING([whether struct rw_semaphore has member activity])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/rwsem.h>
-       ],[
-               struct rw_semaphore dummy_semaphore __attribute__ ((unused));
-               dummy_semaphore.activity = 0;
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_RWSEM_ACTIVITY, 1,
-               [struct rw_semaphore has member activity])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # 4.8 API Change
-dnl #
-dnl # rwsem "->count" changed to atomic_long_t type
-dnl #
-AC_DEFUN([SPL_AC_RWSEM_ATOMIC_LONG_COUNT], [
-       AC_MSG_CHECKING(
-       [whether struct rw_semaphore has atomic_long_t member count])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/rwsem.h>
-       ],[
-               DECLARE_RWSEM(dummy_semaphore);
-               (void) atomic_long_read(&dummy_semaphore.count);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_RWSEM_ATOMIC_LONG_COUNT, 1,
-               [struct rw_semaphore has atomic_long_t member count])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # 3.9 API change,
-dnl # Moved things from linux/sched.h to linux/sched/rt.h
-dnl #
-AC_DEFUN([SPL_AC_SCHED_RT_HEADER],
-       [AC_MSG_CHECKING([whether header linux/sched/rt.h exists])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/sched.h>
-               #include <linux/sched/rt.h>
-       ],[
-               return 0;
-       ],[
-               AC_DEFINE(HAVE_SCHED_RT_HEADER, 1, [linux/sched/rt.h exists])
-               AC_MSG_RESULT(yes)
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 4.11 API change,
-dnl # Moved things from linux/sched.h to linux/sched/signal.h
-dnl #
-AC_DEFUN([SPL_AC_SCHED_SIGNAL_HEADER],
-       [AC_MSG_CHECKING([whether header linux/sched/signal.h exists])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/sched.h>
-               #include <linux/sched/signal.h>
-       ],[
-               return 0;
-       ],[
-               AC_DEFINE(HAVE_SCHED_SIGNAL_HEADER, 1, [linux/sched/signal.h exists])
-               AC_MSG_RESULT(yes)
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 4.11 API, a528d35e@torvalds/linux
-dnl # vfs_getattr(const struct path *p, struct kstat *s, u32 m, unsigned int f)
-dnl #
-AC_DEFUN([SPL_AC_4ARGS_VFS_GETATTR], [
-       AC_MSG_CHECKING([whether vfs_getattr() wants 4 args])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               vfs_getattr((const struct path *)NULL,
-                       (struct kstat *)NULL,
-                       (u32)0,
-                       (unsigned int)0);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_4ARGS_VFS_GETATTR, 1,
-                 [vfs_getattr wants 4 args])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 3.9 API 
-dnl # vfs_getattr(struct path *p, struct kstat *s)
-dnl #
-AC_DEFUN([SPL_AC_2ARGS_VFS_GETATTR], [
-       AC_MSG_CHECKING([whether vfs_getattr() wants 2 args])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               vfs_getattr((struct path *) NULL,
-                       (struct kstat *)NULL);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_2ARGS_VFS_GETATTR, 1,
-                         [vfs_getattr wants 2 args])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # <3.9 API 
-dnl # vfs_getattr(struct vfsmount *v, struct dentry *d, struct kstat *k)
-dnl #
-AC_DEFUN([SPL_AC_3ARGS_VFS_GETATTR], [
-       AC_MSG_CHECKING([whether vfs_getattr() wants 3 args])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               vfs_getattr((struct vfsmount *)NULL,
-                       (struct dentry *)NULL,
-                       (struct kstat *)NULL);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_3ARGS_VFS_GETATTR, 1,
-                 [vfs_getattr wants 3 args])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 2.6.36 API compatibility.
-dnl # Added usleep_range timer.
-dnl # usleep_range is a finer precision implementation of msleep
-dnl # designed to be a drop-in replacement for udelay where a precise
-dnl # sleep / busy-wait is unnecessary.
-dnl #
-AC_DEFUN([SPL_AC_USLEEP_RANGE], [
-       AC_MSG_CHECKING([whether usleep_range() is available])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/delay.h>
-       ],[
-               usleep_range(0, 0);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_USLEEP_RANGE, 1,
-                         [usleep_range is available])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 2.6.35 API change,
-dnl # The cachep->gfpflags member was renamed cachep->allocflags.  These are
-dnl # private allocation flags which are applied when allocating a new slab
-dnl # in kmem_getpages().  Unfortunately there is no public API for setting
-dnl # non-default flags.
-dnl #
-AC_DEFUN([SPL_AC_KMEM_CACHE_ALLOCFLAGS], [
-       AC_MSG_CHECKING([whether struct kmem_cache has allocflags])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/slab.h>
-       ],[
-               struct kmem_cache cachep __attribute__ ((unused));
-               cachep.allocflags = GFP_KERNEL;
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_KMEM_CACHE_ALLOCFLAGS, 1,
-                       [struct kmem_cache has allocflags])
-       ],[
-               AC_MSG_RESULT(no)
-
-               AC_MSG_CHECKING([whether struct kmem_cache has gfpflags])
-               SPL_LINUX_TRY_COMPILE([
-                       #include <linux/slab.h>
-               ],[
-                       struct kmem_cache cachep __attribute__ ((unused));
-                       cachep.gfpflags = GFP_KERNEL;
-               ],[
-                       AC_MSG_RESULT(yes)
-                       AC_DEFINE(HAVE_KMEM_CACHE_GFPFLAGS, 1,
-                               [struct kmem_cache has gfpflags])
-               ],[
-                       AC_MSG_RESULT(no)
-               ])
-       ])
-])
-
-dnl #
-dnl # 3.17 API change,
-dnl # wait_on_bit() no longer requires an action argument. The former
-dnl # "wait_on_bit" interface required an 'action' function to be provided
-dnl # which does the actual waiting. There were over 20 such functions in the
-dnl # kernel, many of them identical, though most cases can be satisfied by one
-dnl # of just two functions: one which uses io_schedule() and one which just
-dnl # uses schedule().  This API change was made to consolidate all of those
-dnl # redundant wait functions.
-dnl #
-AC_DEFUN([SPL_AC_WAIT_ON_BIT], [
-       AC_MSG_CHECKING([whether wait_on_bit() takes an action])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/wait.h>
-       ],[
-               int (*action)(void *) = NULL;
-               wait_on_bit(NULL, 0, action, 0);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_WAIT_ON_BIT_ACTION, 1, [yes])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 4.7 API change
-dnl # i_mutex is changed to i_rwsem. Instead of directly using
-dnl # i_mutex/i_rwsem, we should use inode_lock() and inode_lock_shared()
-dnl # We test inode_lock_shared because inode_lock is introduced earlier.
-dnl #
-AC_DEFUN([SPL_AC_INODE_LOCK], [
-       AC_MSG_CHECKING([whether inode_lock_shared() exists])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               struct inode *inode = NULL;
-               inode_lock_shared(inode);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_INODE_LOCK_SHARED, 1, [yes])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # 4.9 API change
-dnl # group_info changed from 2d array via >blocks to 1d array via ->gid
-dnl #
-AC_DEFUN([SPL_AC_GROUP_INFO_GID], [
-       AC_MSG_CHECKING([whether group_info->gid exists])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/cred.h>
-       ],[
-               struct group_info *gi = groups_alloc(1);
-               gi->gid[0] = KGIDT_INIT(0);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_GROUP_INFO_GID, 1, [group_info->gid exists])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # grsecurity API change,
-dnl # kmem_cache_create() with SLAB_USERCOPY flag replaced by
-dnl # kmem_cache_create_usercopy().
-dnl #
-AC_DEFUN([SPL_AC_KMEM_CACHE_CREATE_USERCOPY], [
-       AC_MSG_CHECKING([whether kmem_cache_create_usercopy() exists])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/slab.h>
-               static void ctor(void *foo)
-               {
-                       // fake ctor
-               }
-       ],[
-               struct kmem_cache *skc_linux_cache;
-               const char *name = "test";
-               size_t size = 4096;
-               size_t align = 8;
-               unsigned long flags = 0;
-               size_t useroffset = 0;
-               size_t usersize = size - useroffset;
-
-               skc_linux_cache = kmem_cache_create_usercopy(
-                       name, size, align, flags, useroffset, usersize, ctor);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_KMEM_CACHE_CREATE_USERCOPY, 1,
-                               [kmem_cache_create_usercopy() exists])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # 4.13 API change
-dnl # Renamed struct wait_queue -> struct wait_queue_entry.
-dnl #
-AC_DEFUN([SPL_AC_WAIT_QUEUE_ENTRY_T], [
-       AC_MSG_CHECKING([whether wait_queue_entry_t exists])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/wait.h>
-       ],[
-               wait_queue_entry_t *entry __attribute__ ((unused));
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_WAIT_QUEUE_ENTRY_T, 1,
-                   [wait_queue_entry_t exists])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 4.13 API change
-dnl # Renamed wait_queue_head::task_list -> wait_queue_head::head
-dnl # Renamed wait_queue_entry::task_list -> wait_queue_entry::entry
-dnl #
-AC_DEFUN([SPL_AC_WAIT_QUEUE_HEAD_ENTRY], [
-       AC_MSG_CHECKING([whether wq_head->head and wq_entry->entry exist])
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/wait.h>
-
-               #ifdef HAVE_WAIT_QUEUE_ENTRY_T
-               typedef wait_queue_head_t       spl_wait_queue_head_t;
-               typedef wait_queue_entry_t      spl_wait_queue_entry_t;
-               #else
-               typedef wait_queue_head_t       spl_wait_queue_head_t;
-               typedef wait_queue_t            spl_wait_queue_entry_t;
-               #endif
-       ],[
-               spl_wait_queue_head_t wq_head;
-               spl_wait_queue_entry_t wq_entry;
-               struct list_head *head __attribute__ ((unused));
-               struct list_head *entry __attribute__ ((unused));
-
-               head = &wq_head.head;
-               entry = &wq_entry.entry;
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_WAIT_QUEUE_HEAD_ENTRY, 1,
-                   [wq_head->head and wq_entry->entry exist])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 3.19 API change
-dnl # The io_schedule_timeout() function is present in all 2.6.32 kernels
-dnl # but it was not exported until Linux 3.19.  The RHEL 7.x kernels which
-dnl # are based on a 3.10 kernel do export this symbol.
-dnl #
-AC_DEFUN([SPL_AC_IO_SCHEDULE_TIMEOUT], [
-       AC_MSG_CHECKING([whether io_schedule_timeout() is available])
-       SPL_LINUX_TRY_COMPILE_SYMBOL([
-               #include <linux/sched.h>
-       ], [
-               (void) io_schedule_timeout(1);
-       ], [io_schedule_timeout], [], [
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_IO_SCHEDULE_TIMEOUT, 1, [yes])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-])
-
-dnl #
-dnl # 4.14 API change
-dnl # kernel_write() which was introduced in 3.9 was updated to take
-dnl # the offset as a pointer which is needed by vn_rdwr().
-dnl #
-AC_DEFUN([SPL_AC_KERNEL_WRITE], [
-       AC_MSG_CHECKING([whether kernel_write() takes loff_t pointer])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               struct file *file = NULL;
-               const void *buf = NULL;
-               size_t count = 0;
-               loff_t *pos = NULL;
-               ssize_t ret;
-
-               ret = kernel_write(file, buf, count, pos);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_KERNEL_WRITE_PPOS, 1,
-                   [kernel_write() take loff_t pointer])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # 4.14 API change
-dnl # kernel_read() which has existed for forever was updated to take
-dnl # the offset as a pointer which is needed by vn_rdwr().
-dnl #
-AC_DEFUN([SPL_AC_KERNEL_READ], [
-       AC_MSG_CHECKING([whether kernel_read() takes loff_t pointer])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/fs.h>
-       ],[
-               struct file *file = NULL;
-               void *buf = NULL;
-               size_t count = 0;
-               loff_t *pos = NULL;
-               ssize_t ret;
-
-               ret = kernel_read(file, buf, count, pos);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_KERNEL_READ_PPOS, 1,
-                   [kernel_read() take loff_t pointer])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])
-
-dnl #
-dnl # 4.15 API change
-dnl # https://lkml.org/lkml/2017/11/25/90
-dnl # Check if timer_list.func get passed a timer_list or an unsigned long
-dnl # (older kernels).  Also sanity check the from_timer() and timer_setup()
-dnl # macros are available as well, since they will be used in the same newer
-dnl # kernels that support the new timer_list.func signature.
-dnl #
-AC_DEFUN([SPL_AC_KERNEL_TIMER_FUNCTION_TIMER_LIST], [
-       AC_MSG_CHECKING([whether timer_list.function gets a timer_list])
-       tmp_flags="$EXTRA_KCFLAGS"
-       EXTRA_KCFLAGS="-Werror"
-       SPL_LINUX_TRY_COMPILE([
-               #include <linux/timer.h>
-               void task_expire(struct timer_list *tl) {}
-       ],[
-               #ifndef from_timer
-               #error "No from_timer() macro"
-               #endif
-
-               struct timer_list timer;
-               timer.function = task_expire;
-               timer_setup(&timer, NULL, 0);
-       ],[
-               AC_MSG_RESULT(yes)
-               AC_DEFINE(HAVE_KERNEL_TIMER_FUNCTION_TIMER_LIST, 1,
-                   [timer_list.function gets a timer_list])
-       ],[
-               AC_MSG_RESULT(no)
-       ])
-       EXTRA_KCFLAGS="$tmp_flags"
-])