Linux 4.12 compat: CURRENT_TIME removed

Linux 4.9 added current_time() as the preferred interface to get
the filesystem time.  CURRENT_TIME was retired in Linux 4.12.

Reviewed-by: Chunwei Chen <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #6114 

7 files changed, 45 insertions, 11 deletions

diff --git a/config/kernel-current-time.m4 b/config/kernel-current-time.m4
new file mode 100644
index 000000000..2ede9ff38
--- /dev/null
+++ b/config/kernel-current-time.m4
@@ -0,0 +1,19 @@
+dnl #
+dnl # 4.9, current_time() added
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_CURRENT_TIME],
+	[AC_MSG_CHECKING([whether current_time() exists])
+	ZFS_LINUX_TRY_COMPILE_SYMBOL([
+		#include <linux/fs.h>
+	], [
+		struct inode ip;
+		struct timespec now __attribute__ ((unused));
+
+		now = current_time(&ip);
+	], [current_time], [fs/inode.c], [
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_CURRENT_TIME, 1, [current_time() exists])
+	], [
+		AC_MSG_RESULT(no)
+	])
+])
diff --git a/config/kernel.m4 b/config/kernel.m4
index 57dad7b3a..c96c8b17f 100644
--- a/config/kernel.m4
+++ b/config/kernel.m4
@@ -118,6 +118,7 @@ AC_DEFUN([ZFS_AC_CONFIG_KERNEL], [
 	ZFS_AC_KERNEL_MODULE_PARAM_CALL_CONST
 	ZFS_AC_KERNEL_RENAME_WANTS_FLAGS
 	ZFS_AC_KERNEL_HAVE_GENERIC_SETXATTR
+	ZFS_AC_KERNEL_CURRENT_TIME
 
 	AS_IF([test "$LINUX_OBJ" != "$LINUX"], [
 		KERNELMAKE_PARAMS="$KERNELMAKE_PARAMS O=$LINUX_OBJ"
diff --git a/include/linux/vfs_compat.h b/include/linux/vfs_compat.h
index 4e61b1d09..0085aa850 100644
--- a/include/linux/vfs_compat.h
+++ b/include/linux/vfs_compat.h
@@ -565,5 +565,16 @@ func(const struct path *path, struct kstat *stat, u32 request_mask,	\
 #error
 #endif
 
+/*
+ * 4.9 API change
+ * Preferred interface to get the current FS time.
+ */
+#if !defined(HAVE_CURRENT_TIME)
+static inline struct timespec
+current_time(struct inode *ip)
+{
+	return (timespec_trunc(current_kernel_time(), ip->i_sb->s_time_gran));
+}
+#endif
 
 #endif /* _ZFS_VFS_H */
diff --git a/module/zfs/zfs_ctldir.c b/module/zfs/zfs_ctldir.c
index eea1bb2e8..0c90532c1 100644
--- a/module/zfs/zfs_ctldir.c
+++ b/module/zfs/zfs_ctldir.c
@@ -451,7 +451,7 @@ static struct inode *
 zfsctl_inode_alloc(zfsvfs_t *zfsvfs, uint64_t id,
     const struct file_operations *fops, const struct inode_operations *ops)
 {
-	struct timespec now = current_fs_time(zfsvfs->z_sb);
+	struct timespec now;
 	struct inode *ip;
 	znode_t *zp;
 
@@ -459,6 +459,7 @@ zfsctl_inode_alloc(zfsvfs_t *zfsvfs, uint64_t id,
 	if (ip == NULL)
 		return (NULL);
 
+	now = current_time(ip);
 	zp = ITOZ(ip);
 	ASSERT3P(zp->z_dirlocks, ==, NULL);
 	ASSERT3P(zp->z_acl_cached, ==, NULL);
diff --git a/module/zfs/zpl_ctldir.c b/module/zfs/zpl_ctldir.c
index bd8af3928..1c5fb34e6 100644
--- a/module/zfs/zpl_ctldir.c
+++ b/module/zfs/zpl_ctldir.c
@@ -103,8 +103,10 @@ static int
 zpl_root_getattr_impl(const struct path *path, struct kstat *stat,
     u32 request_mask, unsigned int query_flags)
 {
-	generic_fillattr(path->dentry->d_inode, stat);
-	stat->atime = CURRENT_TIME;
+	struct inode *ip = path->dentry->d_inode;
+
+	generic_fillattr(ip, stat);
+	stat->atime = current_time(ip);
 
 	return (0);
 }
@@ -377,14 +379,15 @@ static int
 zpl_snapdir_getattr_impl(const struct path *path, struct kstat *stat,
     u32 request_mask, unsigned int query_flags)
 {
-	zfsvfs_t *zfsvfs = ITOZSB(path->dentry->d_inode);
+	struct inode *ip = path->dentry->d_inode;
+	zfsvfs_t *zfsvfs = ITOZSB(ip);
 
 	ZFS_ENTER(zfsvfs);
-	generic_fillattr(path->dentry->d_inode, stat);
+	generic_fillattr(ip, stat);
 
 	stat->nlink = stat->size = 2;
 	stat->ctime = stat->mtime = dmu_objset_snap_cmtime(zfsvfs->z_os);
-	stat->atime = CURRENT_TIME;
+	stat->atime = current_time(ip);
 	ZFS_EXIT(zfsvfs);
 
 	return (0);
@@ -522,7 +525,7 @@ zpl_shares_getattr_impl(const struct path *path, struct kstat *stat,
 	if (zfsvfs->z_shares_dir == 0) {
 		generic_fillattr(path->dentry->d_inode, stat);
 		stat->nlink = stat->size = 2;
-		stat->atime = CURRENT_TIME;
+		stat->atime = current_time(ip);
 		ZFS_EXIT(zfsvfs);
 		return (0);
 	}
diff --git a/module/zfs/zpl_inode.c b/module/zfs/zpl_inode.c
index 8351ab5a0..3b5643d09 100644
--- a/module/zfs/zpl_inode.c
+++ b/module/zfs/zpl_inode.c
@@ -596,7 +596,7 @@ zpl_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
 		return (-EMLINK);
 
 	crhold(cr);
-	ip->i_ctime = CURRENT_TIME_SEC;
+	ip->i_ctime = current_time(ip);
 	igrab(ip); /* Use ihold() if available */
 
 	cookie = spl_fstrans_mark();
diff --git a/module/zfs/zpl_xattr.c b/module/zfs/zpl_xattr.c
index 5edabedd3..d3bb4bbf8 100644
--- a/module/zfs/zpl_xattr.c
+++ b/module/zfs/zpl_xattr.c
@@ -938,7 +938,6 @@ xattr_handler_t zpl_xattr_security_handler = {
 int
 zpl_set_acl(struct inode *ip, struct posix_acl *acl, int type)
 {
-	struct super_block *sb = ITOZSB(ip)->z_sb;
 	char *name, *value = NULL;
 	int error = 0;
 	size_t size = 0;
@@ -964,7 +963,7 @@ zpl_set_acl(struct inode *ip, struct posix_acl *acl, int type)
 				 */
 				if (ip->i_mode != mode) {
 					ip->i_mode = mode;
-					ip->i_ctime = current_fs_time(sb);
+					ip->i_ctime = current_time(ip);
 					zfs_mark_inode_dirty(ip);
 				}
 
@@ -1130,7 +1129,7 @@ zpl_init_acl(struct inode *ip, struct inode *dir)
 
 		if (!acl) {
 			ip->i_mode &= ~current_umask();
-			ip->i_ctime = current_fs_time(ITOZSB(ip)->z_sb);
+			ip->i_ctime = current_time(ip);
 			zfs_mark_inode_dirty(ip);
 			return (0);
 		}