Implement a new type of zfs receive: corrective receive (-c)

This type of recv is used to heal corrupted data when a replica
of the data already exists (in the form of a send file for example).
With the provided send stream, corrective receive will read from
disk blocks described by the WRITE records. When any of the reads
come back with ECKSUM we use the data from the corresponding WRITE
record to rewrite the corrupted block.

Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Paul Zuchowski <pzuchowski@datto.com>
Signed-off-by: Alek Pinchuk <apinchuk@axcient.com>
Closes #9372

include/libzfs_core.h

@@ -21,9 +21,9 @@
 
 /*
  * Copyright (c) 2012, 2020 by Delphix. All rights reserved.
- * Copyright (c) 2017 Datto Inc.
  * Copyright 2017 RackTop Systems.
  * Copyright (c) 2017 Open-E, Inc. All Rights Reserved.
+ * Copyright (c) 2019 Datto Inc.
  */
 
 #ifndef	_LIBZFS_CORE_H
@@ -114,6 +114,10 @@ _LIBZFS_CORE_H int lzc_receive_with_cmdprops(const char *, nvlist_t *,
     nvlist_t *, uint8_t *, uint_t, const char *, boolean_t, boolean_t,
     boolean_t, int, const struct dmu_replay_record *, int, uint64_t *,
     uint64_t *, uint64_t *, nvlist_t **);
+_LIBZFS_CORE_H int lzc_receive_with_heal(const char *, nvlist_t *, nvlist_t *,
+    uint8_t *, uint_t, const char *, boolean_t, boolean_t, boolean_t, boolean_t,
+    int, const struct dmu_replay_record *, int, uint64_t *, uint64_t *,
+    uint64_t *, nvlist_t **);
 _LIBZFS_CORE_H int lzc_send_space(const char *, const char *,
     enum lzc_send_flags, uint64_t *);
 _LIBZFS_CORE_H int lzc_send_space_resume_redacted(const char *, const char *,