MFC r324163: MFV r323530,r323533,r323534: 7431 ZFS Channel Programs, and followups

Also MFC-ed are the following fixes:
- r324164 Add several new files to the files enabled by ZFS kernel option
- r324178 unbreak kernel builds on sparc64 and powerpc
- r324194 fix incorrect use of getzfsvfs_impl in r324163
- r324292 really unbreak kernel builds on sparc64 and powerpc64

1 files changed, 61 insertions, 2 deletions

diff --git a/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c b/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c
index c38c8c6..d4ae782 100644
--- a/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c
+++ b/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c
@@ -20,7 +20,7 @@
  */
 
 /*
- * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
+ * Copyright (c) 2012, 2016 by Delphix. All rights reserved.
  * Copyright (c) 2013 Steven Hartland. All rights reserved.
  * Copyright (c) 2014 Integros [integros.com]
  * Copyright 2017 RackTop Systems.
@@ -174,7 +174,15 @@ lzc_ioctl(zfs_ioc_t ioc, const char *name,
 	}
 
 	while (ioctl(g_fd, ioc, &zc) != 0) {
-		if (errno == ENOMEM && resultp != NULL) {
+		/*
+		 * If ioctl exited with ENOMEM, we retry the ioctl after
+		 * increasing the size of the destination nvlist.
+		 *
+		 * Channel programs that exit with ENOMEM probably ran over the
+		 * lua memory sandbox; they should not be retried.
+		 */
+		if (errno == ENOMEM && resultp != NULL &&
+		    ioc != ZFS_IOC_CHANNEL_PROGRAM) {
 			free((void *)(uintptr_t)zc.zc_nvlist_dst);
 			zc.zc_nvlist_dst_size *= 2;
 			zc.zc_nvlist_dst = (uint64_t)(uintptr_t)
@@ -904,3 +912,54 @@ lzc_destroy_bookmarks(nvlist_t *bmarks, nvlist_t **errlist)
 
 	return (error);
 }
+
+/*
+ * Executes a channel program.
+ *
+ * If this function returns 0 the channel program was successfully loaded and
+ * ran without failing. Note that individual commands the channel program ran
+ * may have failed and the channel program is responsible for reporting such
+ * errors through outnvl if they are important.
+ *
+ * This method may also return:
+ *
+ * EINVAL   The program contains syntax errors, or an invalid memory or time
+ *          limit was given. No part of the channel program was executed.
+ *          If caused by syntax errors, 'outnvl' contains information about the
+ *          errors.
+ *
+ * EDOM     The program was executed, but encountered a runtime error, such as
+ *          calling a function with incorrect arguments, invoking the error()
+ *          function directly, failing an assert() command, etc. Some portion
+ *          of the channel program may have executed and committed changes.
+ *          Information about the failure can be found in 'outnvl'.
+ *
+ * ENOMEM   The program fully executed, but the output buffer was not large
+ *          enough to store the returned value. No output is returned through
+ *          'outnvl'.
+ *
+ * ENOSPC   The program was terminated because it exceeded its memory usage
+ *          limit. Some portion of the channel program may have executed and
+ *          committed changes to disk. No output is returned through 'outnvl'.
+ *
+ * ETIMEDOUT The program was terminated because it exceeded its Lua instruction
+ *           limit. Some portion of the channel program may have executed and
+ *           committed changes to disk. No output is returned through 'outnvl'.
+ */
+int
+lzc_channel_program(const char *pool, const char *program, uint64_t instrlimit,
+    uint64_t memlimit, nvlist_t *argnvl, nvlist_t **outnvl)
+{
+	int error;
+	nvlist_t *args;
+
+	args = fnvlist_alloc();
+	fnvlist_add_string(args, ZCP_ARG_PROGRAM, program);
+	fnvlist_add_nvlist(args, ZCP_ARG_ARGLIST, argnvl);
+	fnvlist_add_uint64(args, ZCP_ARG_INSTRLIMIT, instrlimit);
+	fnvlist_add_uint64(args, ZCP_ARG_MEMLIMIT, memlimit);
+	error = lzc_ioctl(ZFS_IOC_CHANNEL_PROGRAM, pool, args, outnvl);
+	fnvlist_free(args);
+
+	return (error);
+}