Illumos 4757, 4913

[mirror_zfs.git] / module / zfs / bpobj.c

diff --git a/module/zfs/bpobj.c b/module/zfs/bpobj.c
index eb3233b1044f986141465801d7163ab11f0b07fc..7c8f932f5cf316941bb27935db9de04274b62951 100644 (file)
--- a/module/zfs/bpobj.c
+++ b/module/zfs/bpobj.c
@@ -192,6 +192,13 @@ bpobj_close(bpobj_t *bpo)
        mutex_destroy(&bpo->bpo_lock);
 }
 
+static boolean_t
+bpobj_hasentries(bpobj_t *bpo)
+{
+       return (bpo->bpo_phys->bpo_num_blkptrs != 0 ||
+           (bpo->bpo_havesubobj && bpo->bpo_phys->bpo_num_subobjs != 0));
+}
+
 static int
 bpobj_iterate_impl(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx,
     boolean_t free)
@@ -332,9 +339,11 @@ bpobj_iterate_impl(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx,
 
 out:
        /* If there are no entries, there should be no bytes. */
-       ASSERT(bpo->bpo_phys->bpo_num_blkptrs > 0 ||
-           (bpo->bpo_havesubobj && bpo->bpo_phys->bpo_num_subobjs > 0) ||
-           bpo->bpo_phys->bpo_bytes == 0);
+       if (!bpobj_hasentries(bpo)) {
+               ASSERT0(bpo->bpo_phys->bpo_bytes);
+               ASSERT0(bpo->bpo_phys->bpo_comp);
+               ASSERT0(bpo->bpo_phys->bpo_uncomp);
+       }
 
        mutex_exit(&bpo->bpo_lock);
        return (err);
@@ -378,7 +387,7 @@ bpobj_enqueue_subobj(bpobj_t *bpo, uint64_t subobj, dmu_tx_t *tx)
        VERIFY3U(0, ==, bpobj_open(&subbpo, bpo->bpo_os, subobj));
        VERIFY3U(0, ==, bpobj_space(&subbpo, &used, &comp, &uncomp));
 
-       if (used == 0) {
+       if (!bpobj_hasentries(&subbpo)) {
                /* No point in having an empty subobj. */
                bpobj_close(&subbpo);
                bpobj_free(bpo->bpo_os, subobj, tx);
@@ -453,13 +462,29 @@ bpobj_enqueue(bpobj_t *bpo, const blkptr_t *bp, dmu_tx_t *tx)
        ASSERT(!BP_IS_HOLE(bp));
        ASSERT(bpo->bpo_object != dmu_objset_pool(bpo->bpo_os)->dp_empty_bpobj);
 
+       if (BP_IS_EMBEDDED(bp)) {
+               /*
+                * The bpobj will compress better without the payload.
+                *
+                * Note that we store EMBEDDED bp's because they have an
+                * uncompressed size, which must be accounted for.  An
+                * alternative would be to add their size to bpo_uncomp
+                * without storing the bp, but that would create additional
+                * complications: bpo_uncomp would be inconsistent with the
+                * set of BP's stored, and bpobj_iterate() wouldn't visit
+                * all the space accounted for in the bpobj.
+                */
+               bzero(&stored_bp, sizeof (stored_bp));
+               stored_bp.blk_prop = bp->blk_prop;
+               stored_bp.blk_birth = bp->blk_birth;
+       } else if (!BP_GET_DEDUP(bp)) {
+               /* The bpobj will compress better without the checksum */
+               bzero(&stored_bp.blk_cksum, sizeof (stored_bp.blk_cksum));
+       }
+
        /* We never need the fill count. */
        stored_bp.blk_fill = 0;
 
-       /* The bpobj will compress better if we can leave off the checksum */
-       if (!BP_GET_DEDUP(bp))
-               bzero(&stored_bp.blk_cksum, sizeof (stored_bp.blk_cksum));
-
        mutex_enter(&bpo->bpo_lock);
 
        offset = bpo->bpo_phys->bpo_num_blkptrs * sizeof (stored_bp);