Btrfs: return old and new total ref mods when adding delayed refs

We need this to decide when to account pinned bytes.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Signed-off-by: David Sterba <dsterba@suse.com>

3 files changed, 52 insertions, 34 deletions

diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index be70d90dfee5..93ffa898df6d 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -470,7 +470,8 @@ add_tail:
 static noinline void
 update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs,
                          struct btrfs_delayed_ref_node *existing,
-                         struct btrfs_delayed_ref_node *update)
+                         struct btrfs_delayed_ref_node *update,
+                         int *old_ref_mod_ret)
 {
         struct btrfs_delayed_ref_head *existing_ref;
         struct btrfs_delayed_ref_head *ref;
@@ -523,6 +524,8 @@ update_existing_head_ref(struct btrfs_delayed_ref_root *delayed_refs,
          * currently, for refs we just added we know we're a-ok.
          */
         old_ref_mod = existing_ref->total_ref_mod;
+        if (old_ref_mod_ret)
+                *old_ref_mod_ret = old_ref_mod;
         existing->ref_mod += update->ref_mod;
         existing_ref->total_ref_mod += update->ref_mod;
 
@@ -550,7 +553,8 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info,
                      struct btrfs_delayed_ref_node *ref,
                      struct btrfs_qgroup_extent_record *qrecord,
                      u64 bytenr, u64 num_bytes, u64 ref_root, u64 reserved,
-                     int action, int is_data, int *qrecord_inserted_ret)
+                     int action, int is_data, int *qrecord_inserted_ret,
+                     int *old_ref_mod, int *new_ref_mod)
 {
         struct btrfs_delayed_ref_head *existing;
         struct btrfs_delayed_ref_head *head_ref = NULL;
@@ -638,7 +642,8 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info,
         if (existing) {
                 WARN_ON(ref_root && reserved && existing->qgroup_ref_root
                         && existing->qgroup_reserved);
-                update_existing_head_ref(delayed_refs, &existing->node, ref);
+                update_existing_head_ref(delayed_refs, &existing->node, ref,
+                                         old_ref_mod);
                 /*
                  * we've updated the existing ref, free the newly
                  * allocated ref
@@ -646,6 +651,8 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info,
                 kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
                 head_ref = existing;
         } else {
+                if (old_ref_mod)
+                        *old_ref_mod = 0;
                 if (is_data && count_mod < 0)
                         delayed_refs->pending_csums += num_bytes;
                 delayed_refs->num_heads++;
@@ -655,6 +662,8 @@ add_delayed_ref_head(struct btrfs_fs_info *fs_info,
         }
         if (qrecord_inserted_ret)
                 *qrecord_inserted_ret = qrecord_inserted;
+        if (new_ref_mod)
+                *new_ref_mod = head_ref->total_ref_mod;
         return head_ref;
 }
 
@@ -778,7 +787,8 @@ int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
                                struct btrfs_trans_handle *trans,
                                u64 bytenr, u64 num_bytes, u64 parent,
                                u64 ref_root,  int level, int action,
-                               struct btrfs_delayed_extent_op *extent_op)
+                               struct btrfs_delayed_extent_op *extent_op,
+                               int *old_ref_mod, int *new_ref_mod)
 {
         struct btrfs_delayed_tree_ref *ref;
         struct btrfs_delayed_ref_head *head_ref;
@@ -813,7 +823,8 @@ int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
          */
         head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, record,
                                         bytenr, num_bytes, 0, 0, action, 0,
-                                        &qrecord_inserted);
+                                        &qrecord_inserted, old_ref_mod,
+                                        new_ref_mod);
 
         add_delayed_tree_ref(fs_info, trans, head_ref, &ref->node, bytenr,
                              num_bytes, parent, ref_root, level, action);
@@ -838,7 +849,8 @@ int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info,
                                struct btrfs_trans_handle *trans,
                                u64 bytenr, u64 num_bytes,
                                u64 parent, u64 ref_root,
-                               u64 owner, u64 offset, u64 reserved, int action)
+                               u64 owner, u64 offset, u64 reserved, int action,
+                               int *old_ref_mod, int *new_ref_mod)
 {
         struct btrfs_delayed_data_ref *ref;
         struct btrfs_delayed_ref_head *head_ref;
@@ -878,7 +890,8 @@ int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info,
          */
         head_ref = add_delayed_ref_head(fs_info, trans, &head_ref->node, record,
                                         bytenr, num_bytes, ref_root, reserved,
-                                        action, 1, &qrecord_inserted);
+                                        action, 1, &qrecord_inserted,
+                                        old_ref_mod, new_ref_mod);
 
         add_delayed_data_ref(fs_info, trans, head_ref, &ref->node, bytenr,
                                    num_bytes, parent, ref_root, owner, offset,
@@ -909,7 +922,7 @@ int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info,
 
         add_delayed_ref_head(fs_info, trans, &head_ref->node, NULL, bytenr,
                              num_bytes, 0, 0, BTRFS_UPDATE_DELAYED_HEAD,
-                             extent_op->is_data, NULL);
+                             extent_op->is_data, NULL, NULL, NULL);
 
         spin_unlock(&delayed_refs->lock);
         return 0;
diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h
index c0264ff01b53..ce88e4ac5276 100644
--- a/fs/btrfs/delayed-ref.h
+++ b/fs/btrfs/delayed-ref.h
@@ -247,12 +247,14 @@ int btrfs_add_delayed_tree_ref(struct btrfs_fs_info *fs_info,
                                struct btrfs_trans_handle *trans,
                                u64 bytenr, u64 num_bytes, u64 parent,
                                u64 ref_root, int level, int action,
-                               struct btrfs_delayed_extent_op *extent_op);
+                               struct btrfs_delayed_extent_op *extent_op,
+                               int *old_ref_mod, int *new_ref_mod);
 int btrfs_add_delayed_data_ref(struct btrfs_fs_info *fs_info,
                                struct btrfs_trans_handle *trans,
                                u64 bytenr, u64 num_bytes,
                                u64 parent, u64 ref_root,
-                               u64 owner, u64 offset, u64 reserved, int action);
+                               u64 owner, u64 offset, u64 reserved, int action,
+                               int *old_ref_mod, int *new_ref_mod);
 int btrfs_add_delayed_extent_op(struct btrfs_fs_info *fs_info,
                                 struct btrfs_trans_handle *trans,
                                 u64 bytenr, u64 num_bytes,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 40c80ed8d1f9..8121a78f6cbd 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2120,14 +2120,16 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 
         if (owner < BTRFS_FIRST_FREE_OBJECTID) {
                 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
-                                        num_bytes,
-                                        parent, root_objectid, (int)owner,
-                                        BTRFS_ADD_DELAYED_REF, NULL);
+                                                 num_bytes, parent,
+                                                 root_objectid, (int)owner,
+                                                 BTRFS_ADD_DELAYED_REF, NULL,
+                                                 NULL, NULL);
         } else {
                 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
-                                        num_bytes, parent, root_objectid,
-                                        owner, offset, 0,
-                                        BTRFS_ADD_DELAYED_REF);
+                                                 num_bytes, parent,
+                                                 root_objectid, owner, offset,
+                                                 0, BTRFS_ADD_DELAYED_REF, NULL,
+                                                 NULL);
         }
         return ret;
 }
@@ -7184,12 +7186,12 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
         int ret;
 
         if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
-                ret = btrfs_add_delayed_tree_ref(fs_info, trans,
-                                                 buf->start, buf->len,
-                                                 parent,
+                ret = btrfs_add_delayed_tree_ref(fs_info, trans, buf->start,
+                                                 buf->len, parent,
                                                  root->root_key.objectid,
                                                  btrfs_header_level(buf),
-                                                 BTRFS_DROP_DELAYED_REF, NULL);
+                                                 BTRFS_DROP_DELAYED_REF, NULL,
+                                                 NULL, NULL);
                 BUG_ON(ret); /* -ENOMEM */
         }
 
@@ -7257,15 +7259,16 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
                 ret = 0;
         } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
                 ret = btrfs_add_delayed_tree_ref(fs_info, trans, bytenr,
-                                        num_bytes,
-                                        parent, root_objectid, (int)owner,
-                                        BTRFS_DROP_DELAYED_REF, NULL);
+                                                 num_bytes, parent,
+                                                 root_objectid, (int)owner,
+                                                 BTRFS_DROP_DELAYED_REF, NULL,
+                                                 NULL, NULL);
         } else {
                 ret = btrfs_add_delayed_data_ref(fs_info, trans, bytenr,
-                                                num_bytes,
-                                                parent, root_objectid, owner,
-                                                offset, 0,
-                                                BTRFS_DROP_DELAYED_REF);
+                                                 num_bytes, parent,
+                                                 root_objectid, owner, offset,
+                                                 0, BTRFS_DROP_DELAYED_REF,
+                                                 NULL, NULL);
         }
         return ret;
 }
@@ -8213,9 +8216,9 @@ int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
         BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
 
         ret = btrfs_add_delayed_data_ref(fs_info, trans, ins->objectid,
-                                         ins->offset, 0,
-                                         root_objectid, owner, offset,
-                                         ram_bytes, BTRFS_ADD_DELAYED_EXTENT);
+                                         ins->offset, 0, root_objectid, owner,
+                                         offset, ram_bytes,
+                                         BTRFS_ADD_DELAYED_EXTENT, NULL, NULL);
         return ret;
 }
 
@@ -8435,11 +8438,11 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
                 extent_op->is_data = false;
                 extent_op->level = level;
 
-                ret = btrfs_add_delayed_tree_ref(fs_info, trans,
-                                                 ins.objectid, ins.offset,
-                                                 parent, root_objectid, level,
+                ret = btrfs_add_delayed_tree_ref(fs_info, trans, ins.objectid,
+                                                 ins.offset, parent,
+                                                 root_objectid, level,
                                                  BTRFS_ADD_DELAYED_EXTENT,
-                                                 extent_op);
+                                                 extent_op, NULL, NULL);
                 if (ret)
                         goto out_free_delayed;
         }