Add .zfs control directory

Add support for the .zfs control directory. This was accomplished by leveraging as much of the existing ZFS infrastructure as posible and updating it for Linux as required. The bulk of the core functionality is now all there with the following limitations. *) The .zfs/snapshot directory automount support requires a 2.6.37 or newer kernel. The exception is RHEL6.2 which has backported the d_automount patches. *) Creating/destroying/renaming snapshots with mkdir/rmdir/mv in the .zfs/snapshot directory works as expected. However, this functionality is only available to root until zfs delegations are finished. * mkdir - create a snapshot * rmdir - destroy a snapshot * mv - rename a snapshot The following issues are known defeciences, but we expect them to be addressed by future commits. *) Add automount support for kernels older the 2.6.37. This should be possible using follow_link() which is what Linux did before. *) Accessing the .zfs/snapshot directory via NFS is not yet possible. The majority of the ground work for this is complete. However, finishing this work will require resolving some lingering integration issues with the Linux NFS kernel server. *) The .zfs/shares directory exists but no futher smb functionality has yet been implemented. Contributions-by: Rohan Puri <[email protected]> Contributiobs-by: Andrew Barnes <[email protected]> Signed-off-by: Brian Behlendorf <[email protected]> Closes openzfs#173
nosuz · Mar 22, 2012 · ebe7e57 · ebe7e57
1 parent 49be0cc
commit ebe7e57
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Showing 79 changed files with 2,037 additions and 101 deletions.
diff --git a/Makefile.in b/Makefile.in
@@ -62,6 +62,7 @@ subdir = .
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/Makefile.in b/cmd/Makefile.in
@@ -39,6 +39,7 @@ DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/mount_zfs/Makefile.in b/cmd/mount_zfs/Makefile.in
@@ -42,6 +42,7 @@ subdir = cmd/mount_zfs
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/sas_switch_id/Makefile.in b/cmd/sas_switch_id/Makefile.in
@@ -41,6 +41,7 @@ DIST_COMMON = $(dist_udev_SCRIPTS) $(srcdir)/Makefile.am \
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/zdb/Makefile.in b/cmd/zdb/Makefile.in
@@ -42,6 +42,7 @@ subdir = cmd/zdb
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/zfs/Makefile.in b/cmd/zfs/Makefile.in
@@ -42,6 +42,7 @@ subdir = cmd/zfs
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/zinject/Makefile.in b/cmd/zinject/Makefile.in
@@ -42,6 +42,7 @@ subdir = cmd/zinject
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/zpios/Makefile.in b/cmd/zpios/Makefile.in
@@ -42,6 +42,7 @@ subdir = cmd/zpios
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/zpool/Makefile.in b/cmd/zpool/Makefile.in
@@ -42,6 +42,7 @@ subdir = cmd/zpool
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/zpool_id/Makefile.in b/cmd/zpool_id/Makefile.in
@@ -41,6 +41,7 @@ DIST_COMMON = $(dist_udev_SCRIPTS) $(srcdir)/Makefile.am \
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/zpool_layout/Makefile.in b/cmd/zpool_layout/Makefile.in
@@ -41,6 +41,7 @@ DIST_COMMON = $(dist_bin_SCRIPTS) $(srcdir)/Makefile.am \
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/ztest/Makefile.in b/cmd/ztest/Makefile.in
@@ -42,6 +42,7 @@ subdir = cmd/ztest
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/cmd/zvol_id/Makefile.in b/cmd/zvol_id/Makefile.in
@@ -42,6 +42,7 @@ subdir = cmd/zvol_id
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/config/kernel-automount.m4 b/config/kernel-automount.m4
@@ -0,0 +1,23 @@
+dnl #
+dnl # 2.6.37 API change
+dnl # The dops->d_automount() dentry operation was added as a clean
+dnl # solution to handling automounts.  Prior to this cifs/nfs clients
+dnl # which required automount support would abuse the follow_link()
+dnl # operation on directories for this purpose.
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_AUTOMOUNT], [
+	AC_MSG_CHECKING([whether dops->d_automount() exists])
+	ZFS_LINUX_TRY_COMPILE([
+		#include <linux/dcache.h>
+	],[
+		struct vfsmount *(*d_automount) (struct path *) = NULL;
+		struct dentry_operations dops __attribute__ ((unused)) = {
+			.d_automount = d_automount,
+		};
+	],[
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_AUTOMOUNT, 1, [dops->automount() exists])
+	],[
+		AC_MSG_RESULT(no)
+	])
+])
diff --git a/config/kernel.m4 b/config/kernel.m4
@@ -45,6 +45,7 @@ AC_DEFUN([ZFS_AC_CONFIG_KERNEL], [
 	ZFS_AC_KERNEL_NR_CACHED_OBJECTS
 	ZFS_AC_KERNEL_FREE_CACHED_OBJECTS
 	ZFS_AC_KERNEL_FALLOCATE
+	ZFS_AC_KERNEL_AUTOMOUNT
 	ZFS_AC_KERNEL_INSERT_INODE_LOCKED
 	ZFS_AC_KERNEL_D_OBTAIN_ALIAS
 	ZFS_AC_KERNEL_CHECK_DISK_SIZE_CHANGE

diff --git a/configure b/configure
@@ -15681,6 +15681,74 @@ fi
 
 
 
+	{ $as_echo "$as_me:$LINENO: checking whether dops->d_automount() exists" >&5
+$as_echo_n "checking whether dops->d_automount() exists... " >&6; }
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/dcache.h>
+
+int
+main (void)
+{
+
+		struct vfsmount *(*d_automount) (struct path *) = NULL;
+		struct dentry_operations dops __attribute__ ((unused)) = {
+			.d_automount = d_automount,
+		};
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: yes" >&5
+$as_echo "yes" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_AUTOMOUNT 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+		{ $as_echo "$as_me:$LINENO: result: no" >&5
+$as_echo "no" >&6; }
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
 	{ $as_echo "$as_me:$LINENO: checking whether symbol insert_inode_locked is exported" >&5
 $as_echo_n "checking whether symbol insert_inode_locked is exported... " >&6; }
 	grep -q -E '[[:space:]]insert_inode_locked[[:space:]]' \
@@ -21568,6 +21636,74 @@ fi
 
 
 
+	{ $as_echo "$as_me:$LINENO: checking whether dops->d_automount() exists" >&5
+$as_echo_n "checking whether dops->d_automount() exists... " >&6; }
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/dcache.h>
+
+int
+main (void)
+{
+
+		struct vfsmount *(*d_automount) (struct path *) = NULL;
+		struct dentry_operations dops __attribute__ ((unused)) = {
+			.d_automount = d_automount,
+		};
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: yes" >&5
+$as_echo "yes" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_AUTOMOUNT 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+		{ $as_echo "$as_me:$LINENO: result: no" >&5
+$as_echo "no" >&6; }
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
 	{ $as_echo "$as_me:$LINENO: checking whether symbol insert_inode_locked is exported" >&5
 $as_echo_n "checking whether symbol insert_inode_locked is exported... " >&6; }
 	grep -q -E '[[:space:]]insert_inode_locked[[:space:]]' \

diff --git a/dracut/90zfs/Makefile.in b/dracut/90zfs/Makefile.in
@@ -40,6 +40,7 @@ DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/dracut/Makefile.in b/dracut/Makefile.in
@@ -39,6 +39,7 @@ DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/etc/Makefile.in b/etc/Makefile.in
@@ -39,6 +39,7 @@ DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/etc/init.d/Makefile.in b/etc/init.d/Makefile.in
@@ -40,6 +40,7 @@ DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/etc/zfs/Makefile.in b/etc/zfs/Makefile.in
@@ -40,6 +40,7 @@ DIST_COMMON = $(srcdir)/Makefile.am $(srcdir)/Makefile.in
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/include/Makefile.in b/include/Makefile.in
@@ -41,6 +41,7 @@ DIST_COMMON = $(am__kernel_HEADERS_DIST) $(am__libzfs_HEADERS_DIST) \
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/include/linux/Makefile.in b/include/linux/Makefile.in
@@ -41,6 +41,7 @@ DIST_COMMON = $(am__kernel_HEADERS_DIST) $(libzfs_HEADERS) \
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \

diff --git a/include/linux/dcache_compat.h b/include/linux/dcache_compat.h
@@ -29,5 +29,6 @@
 #include <linux/dcache.h>
 
 #define dname(dentry)	((char *)((dentry)->d_name.name))
+#define dlen(dentry)	((int)((dentry)->d_name.len))
 
 #endif /* _ZFS_DCACHE_H */
diff --git a/include/sys/Makefile.am b/include/sys/Makefile.am
@@ -55,6 +55,7 @@ COMMON_H = \
 	$(top_srcdir)/include/sys/zap_leaf.h \
 	$(top_srcdir)/include/sys/zfs_acl.h \
 	$(top_srcdir)/include/sys/zfs_context.h \
+	$(top_srcdir)/include/sys/zfs_ctldir.h \
 	$(top_srcdir)/include/sys/zfs_debug.h \
 	$(top_srcdir)/include/sys/zfs_dir.h \
 	$(top_srcdir)/include/sys/zfs_fuid.h \

diff --git a/include/sys/Makefile.in b/include/sys/Makefile.in
@@ -41,6 +41,7 @@ DIST_COMMON = $(am__kernel_HEADERS_DIST) $(am__libzfs_HEADERS_DIST) \
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps =  \
 	$(top_srcdir)/config/always-no-unused-but-set-variable.m4 \
+	$(top_srcdir)/config/kernel-automount.m4 \
 	$(top_srcdir)/config/kernel-bdev-block-device-operations.m4 \
 	$(top_srcdir)/config/kernel-bdev-logical-size.m4 \
 	$(top_srcdir)/config/kernel-bdi-setup-and-register.m4 \
@@ -170,6 +171,7 @@ am__kernel_HEADERS_DIST = $(top_srcdir)/include/sys/arc.h \
 	$(top_srcdir)/include/sys/zap_leaf.h \
 	$(top_srcdir)/include/sys/zfs_acl.h \
 	$(top_srcdir)/include/sys/zfs_context.h \
+	$(top_srcdir)/include/sys/zfs_ctldir.h \
 	$(top_srcdir)/include/sys/zfs_debug.h \
 	$(top_srcdir)/include/sys/zfs_dir.h \
 	$(top_srcdir)/include/sys/zfs_fuid.h \
@@ -266,6 +268,7 @@ am__libzfs_HEADERS_DIST = $(top_srcdir)/include/sys/arc.h \
 	$(top_srcdir)/include/sys/zap_leaf.h \
 	$(top_srcdir)/include/sys/zfs_acl.h \
 	$(top_srcdir)/include/sys/zfs_context.h \
+	$(top_srcdir)/include/sys/zfs_ctldir.h \
 	$(top_srcdir)/include/sys/zfs_debug.h \
 	$(top_srcdir)/include/sys/zfs_dir.h \
 	$(top_srcdir)/include/sys/zfs_fuid.h \
@@ -550,6 +553,7 @@ COMMON_H = \
 	$(top_srcdir)/include/sys/zap_leaf.h \
 	$(top_srcdir)/include/sys/zfs_acl.h \
 	$(top_srcdir)/include/sys/zfs_context.h \
+	$(top_srcdir)/include/sys/zfs_ctldir.h \
 	$(top_srcdir)/include/sys/zfs_debug.h \
 	$(top_srcdir)/include/sys/zfs_dir.h \
 	$(top_srcdir)/include/sys/zfs_fuid.h \

diff --git a/include/sys/dmu.h b/include/sys/dmu.h
@@ -643,6 +643,7 @@ extern uint64_t dmu_objset_syncprop(objset_t *os);
 extern uint64_t dmu_objset_logbias(objset_t *os);
 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
     uint64_t *id, uint64_t *offp, boolean_t *case_conflict);
+extern int dmu_snapshot_id(objset_t *os, const char *snapname, uint64_t *idp);
 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real,
     int maxlen, boolean_t *conflict);
 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name,