OpenZFS 7431 - ZFS Channel Programs

Authored by: Chris Williamson <[email protected]>
Reviewed by: Matthew Ahrens <[email protected]>
Reviewed by: George Wilson <[email protected]>
Reviewed by: John Kennedy <[email protected]>
Reviewed by: Dan Kimmel <[email protected]>
Approved by: Garrett D'Amore <[email protected]>
Ported-by: Don Brady <[email protected]>
Ported-by: John Kennedy <[email protected]>

OpenZFS-issue: https://www.illumos.org/issues/7431
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/dfc11533

Porting Notes:
* The CLI long option arguments for '-t' and '-m' don't parse on linux
* Switched from kmem_alloc to vmem_alloc in zcp_lua_alloc
* Lua implementation is built as its own module (zlua.ko)
* Lua headers consumed directly by zfs code moved to 'include/sys/lua/'
* There is no native setjmp/longjump available in stock Linux kernel.
  Brought over implementations from illumos and FreeBSD
* The get_temporary_prop() was adapted due to VFS platform differences
* Use of inline functions in lua parser to reduce stack usage per C call
* Skip some ZFS Test Suite ZCP tests on sparc64 to avoid stack overflow

1 files changed, 14 insertions, 2 deletions

diff --git a/module/zfs/zfs_vfsops.c b/module/zfs/zfs_vfsops.c
index 18b4ec3d6..bb380c920 100644
--- a/module/zfs/zfs_vfsops.c
+++ b/module/zfs/zfs_vfsops.c
@@ -1053,13 +1053,26 @@ zfsvfs_create(const char *osname, zfsvfs_t **zfvp)
 	 * We claim to always be readonly so we can open snapshots;
 	 * other ZPL code will prevent us from writing to snapshots.
 	 */
+
 	error = dmu_objset_own(osname, DMU_OST_ZFS, B_TRUE, B_TRUE,
 	    zfsvfs, &os);
-	if (error) {
+	if (error != 0) {
 		kmem_free(zfsvfs, sizeof (zfsvfs_t));
 		return (error);
 	}
 
+	error = zfsvfs_create_impl(zfvp, zfsvfs, os);
+	if (error != 0) {
+		dmu_objset_disown(os, B_TRUE, zfsvfs);
+	}
+	return (error);
+}
+
+int
+zfsvfs_create_impl(zfsvfs_t **zfvp, zfsvfs_t *zfsvfs, objset_t *os)
+{
+	int error;
+
 	zfsvfs->z_vfs = NULL;
 	zfsvfs->z_sb = NULL;
 	zfsvfs->z_parent = zfsvfs;
@@ -1086,7 +1099,6 @@ zfsvfs_create(const char *osname, zfsvfs_t **zfvp)
 
 	error = zfsvfs_init(zfsvfs, os);
 	if (error != 0) {
-		dmu_objset_disown(os, B_TRUE, zfsvfs);
 		*zfvp = NULL;
 		kmem_free(zfsvfs, sizeof (zfsvfs_t));
 		return (error);