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, 69 insertions, 11 deletions

diff --git a/module/zfs/zfs_ioctl.c b/module/zfs/zfs_ioctl.c
index b132a6885..a8f37fe84 100644
--- a/module/zfs/zfs_ioctl.c
+++ b/module/zfs/zfs_ioctl.c
@@ -27,7 +27,7 @@
  * Copyright (c) 2014, 2016 Joyent, Inc. All rights reserved.
  * Copyright 2016 Nexenta Systems, Inc.  All rights reserved.
  * Copyright (c) 2014, Joyent, Inc. All rights reserved.
- * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
+ * Copyright (c) 2011, 2016 by Delphix. All rights reserved.
  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  * Copyright (c) 2013 Steven Hartland. All rights reserved.
  * Copyright (c) 2014 Integros [integros.com]
@@ -193,6 +193,7 @@
 #include <sys/dsl_bookmark.h>
 #include <sys/dsl_userhold.h>
 #include <sys/zfeature.h>
+#include <sys/zcp.h>
 #include <sys/zio_checksum.h>
 
 #include <linux/miscdevice.h>
@@ -203,6 +204,9 @@
 #include "zfs_deleg.h"
 #include "zfs_comutil.h"
 
+#include <sys/lua/lua.h>
+#include <sys/lua/lauxlib.h>
+
 /*
  * Limit maximum nvlist size.  We don't want users passing in insane values
  * for zc->zc_nvlist_src_size, since we will need to allocate that much memory.
@@ -1414,17 +1418,11 @@ put_nvlist(zfs_cmd_t *zc, nvlist_t *nvl)
 	return (error);
 }
 
-static int
-getzfsvfs(const char *dsname, zfsvfs_t **zfvp)
+int
+getzfsvfs_impl(objset_t *os, zfsvfs_t **zfvp)
 {
-	objset_t *os;
-	int error;
-
-	error = dmu_objset_hold(dsname, FTAG, &os);
-	if (error != 0)
-		return (error);
+	int error = 0;
 	if (dmu_objset_type(os) != DMU_OST_ZFS) {
-		dmu_objset_rele(os, FTAG);
 		return (SET_ERROR(EINVAL));
 	}
 
@@ -1436,6 +1434,20 @@ getzfsvfs(const char *dsname, zfsvfs_t **zfvp)
 		error = SET_ERROR(ESRCH);
 	}
 	mutex_exit(&os->os_user_ptr_lock);
+	return (error);
+}
+
+static int
+getzfsvfs(const char *dsname, zfsvfs_t **zfvp)
+{
+	objset_t *os;
+	int error;
+
+	error = dmu_objset_hold(dsname, FTAG, &os);
+	if (error != 0)
+		return (error);
+
+	error = getzfsvfs_impl(os, zfvp);
 	dmu_objset_rele(os, FTAG);
 	return (error);
 }
@@ -3660,6 +3672,36 @@ zfs_ioc_destroy_bookmarks(const char *poolname, nvlist_t *innvl,
 	return (error);
 }
 
+static int
+zfs_ioc_channel_program(const char *poolname, nvlist_t *innvl,
+    nvlist_t *outnvl)
+{
+	char *program;
+	uint64_t instrlimit, memlimit;
+	nvpair_t *nvarg = NULL;
+
+	if (0 != nvlist_lookup_string(innvl, ZCP_ARG_PROGRAM, &program)) {
+		return (EINVAL);
+	}
+	if (0 != nvlist_lookup_uint64(innvl, ZCP_ARG_INSTRLIMIT, &instrlimit)) {
+		instrlimit = ZCP_DEFAULT_INSTRLIMIT;
+	}
+	if (0 != nvlist_lookup_uint64(innvl, ZCP_ARG_MEMLIMIT, &memlimit)) {
+		memlimit = ZCP_DEFAULT_MEMLIMIT;
+	}
+	if (0 != nvlist_lookup_nvpair(innvl, ZCP_ARG_ARGLIST, &nvarg)) {
+		return (EINVAL);
+	}
+
+	if (instrlimit == 0 || instrlimit > zfs_lua_max_instrlimit)
+		return (EINVAL);
+	if (memlimit == 0 || memlimit > ZCP_MAX_MEMLIMIT)
+		return (EINVAL);
+
+	return (zcp_eval(poolname, program, instrlimit, memlimit,
+	    nvarg, outnvl));
+}
+
 /*
  * inputs:
  * zc_name		name of dataset to destroy
@@ -6333,6 +6375,11 @@ zfs_ioctl_init(void)
 	    zfs_secpolicy_config, POOL_NAME, POOL_CHECK_SUSPENDED, B_TRUE,
 	    B_TRUE);
 
+	zfs_ioctl_register("channel_program", ZFS_IOC_CHANNEL_PROGRAM,
+	    zfs_ioc_channel_program, zfs_secpolicy_config,
+	    POOL_NAME, POOL_CHECK_SUSPENDED | POOL_CHECK_READONLY, B_TRUE,
+	    B_TRUE);
+
 	/* IOCTLS that use the legacy function signature */
 
 	zfs_ioctl_register_legacy(ZFS_IOC_POOL_FREEZE, zfs_ioc_pool_freeze,
@@ -6803,12 +6850,23 @@ zfsdev_ioctl(struct file *filp, unsigned cmd, unsigned long arg)
 		error = vec->zvec_func(zc->zc_name, innvl, outnvl);
 		spl_fstrans_unmark(cookie);
 
-		if (error == 0 && vec->zvec_allow_log &&
+		/*
+		 * Some commands can partially execute, modify state, and still
+		 * return an error.  In these cases, attempt to record what
+		 * was modified.
+		 */
+		if ((error == 0 ||
+		    (cmd == ZFS_IOC_CHANNEL_PROGRAM && error != EINVAL)) &&
+		    vec->zvec_allow_log &&
 		    spa_open(zc->zc_name, &spa, FTAG) == 0) {
 			if (!nvlist_empty(outnvl)) {
 				fnvlist_add_nvlist(lognv, ZPOOL_HIST_OUTPUT_NVL,
 				    outnvl);
 			}
+			if (error != 0) {
+				fnvlist_add_int64(lognv, ZPOOL_HIST_ERRNO,
+				    error);
+			}
 			(void) spa_history_log_nvl(spa, lognv);
 			spa_close(spa, FTAG);
 		}