OpenZFS 6513 - partially filled holes lose birth time

Reviewed by: Matthew Ahrens <[email protected]>
Reviewed by: George Wilson <[email protected]>
Reviewed by: Boris Protopopov <[email protected]>
Approved by: Richard Lowe <[email protected]>a
Ported by: Boris Protopopov <[email protected]>
Signed-off-by: Boris Protopopov <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>

OpenZFS-issue: https://www.illumos.org/issues/6513
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/8df0bcf0

If a ZFS object contains a hole at level one, and then a data block is
created at level 0 underneath that l1 block, l0 holes will be created.
However, these l0 holes do not have the birth time property set; as a
result, incremental sends will not send those holes.

Fix is to modify the dbuf_read code to fill in birth time data.

1 files changed, 22 insertions, 9 deletions

diff --git a/module/zfs/zio.c b/module/zfs/zio.c
index 4063703ad..de56a1283 100644
--- a/module/zfs/zio.c
+++ b/module/zfs/zio.c
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
+ * Copyright (c) 2011, 2016 by Delphix. All rights reserved.
  * Copyright (c) 2011 Nexenta Systems, Inc. All rights reserved.
  */
 
@@ -737,9 +737,10 @@ zio_read(zio_t *pio, spa_t *spa, const blkptr_t *bp,
 zio_t *
 zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
     void *data, uint64_t size, const zio_prop_t *zp,
-    zio_done_func_t *ready, zio_done_func_t *physdone, zio_done_func_t *done,
-    void *private,
-    zio_priority_t priority, enum zio_flag flags, const zbookmark_phys_t *zb)
+    zio_done_func_t *ready, zio_done_func_t *children_ready,
+    zio_done_func_t *physdone, zio_done_func_t *done,
+    void *private, zio_priority_t priority, enum zio_flag flags,
+    const zbookmark_phys_t *zb)
 {
 	zio_t *zio;
 
@@ -758,6 +759,7 @@ zio_write(zio_t *pio, spa_t *spa, uint64_t txg, blkptr_t *bp,
 	    ZIO_DDT_CHILD_WRITE_PIPELINE : ZIO_WRITE_PIPELINE);
 
 	zio->io_ready = ready;
+	zio->io_children_ready = children_ready;
 	zio->io_physdone = physdone;
 	zio->io_prop = *zp;
 
@@ -1132,6 +1134,16 @@ zio_write_bp_init(zio_t *zio)
 	if (!IO_IS_ALLOCATING(zio))
 		return (ZIO_PIPELINE_CONTINUE);
 
+	if (zio->io_children_ready != NULL) {
+		/*
+		 * Now that all our children are ready, run the callback
+		 * associated with this zio in case it wants to modify the
+		 * data to be written.
+		 */
+		ASSERT3U(zp->zp_level, >, 0);
+		zio->io_children_ready(zio);
+	}
+
 	ASSERT(zio->io_child_type != ZIO_CHILD_DDT);
 
 	if (zio->io_bp_override) {
@@ -2143,9 +2155,9 @@ zio_write_gang_block(zio_t *pio)
 
 		zio_nowait(zio_write(zio, spa, txg, &gbh->zg_blkptr[g],
 		    (char *)pio->io_data + (pio->io_size - resid), lsize, &zp,
-		    zio_write_gang_member_ready, NULL, NULL, &gn->gn_child[g],
-		    pio->io_priority, ZIO_GANG_CHILD_FLAGS(pio),
-		    &pio->io_bookmark));
+		    zio_write_gang_member_ready, NULL, NULL, NULL,
+		    &gn->gn_child[g], pio->io_priority,
+		    ZIO_GANG_CHILD_FLAGS(pio), &pio->io_bookmark));
 	}
 
 	/*
@@ -2528,7 +2540,7 @@ zio_ddt_write(zio_t *zio)
 
 		dio = zio_write(zio, spa, txg, bp, zio->io_orig_data,
 		    zio->io_orig_size, &czp, NULL, NULL,
-		    zio_ddt_ditto_write_done, dde, zio->io_priority,
+		    NULL, zio_ddt_ditto_write_done, dde, zio->io_priority,
 		    ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark);
 
 		zio_push_transform(dio, zio->io_data, zio->io_size, 0, NULL);
@@ -2549,7 +2561,8 @@ zio_ddt_write(zio_t *zio)
 		ddt_phys_addref(ddp);
 	} else {
 		cio = zio_write(zio, spa, txg, bp, zio->io_orig_data,
-		    zio->io_orig_size, zp, zio_ddt_child_write_ready, NULL,
+		    zio->io_orig_size, zp,
+		    zio_ddt_child_write_ready, NULL, NULL,
 		    zio_ddt_child_write_done, dde, zio->io_priority,
 		    ZIO_DDT_CHILD_FLAGS(zio), &zio->io_bookmark);