btrfs: track owning root in btrfs_ref

While data extents require us to store additional inline refs to track
the original owner on free, this information is available implicitly for
metadata. It is found in the owner field of the header of the tree
block. Even if other trees refer to this block and the original ref goes
away, we will not rewrite that header field, so it will reliably give the
original owner.

In addition, there is a relocation case where a new data extent needs to
have an owning root separate from the referring root wired through
delayed refs.

To use it for recording simple quota deltas, we need to wire this root
id through from when we create the delayed ref until we fully process
it. Store it in the generic btrfs_ref struct of the delayed ref.

Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/delayed-ref.h b/fs/btrfs/delayed-ref.h
index a7fdb28df1cda4150eafc50d4293abf906771df1..84b37888bff3c45a820bd85c7beee094cb5c6338 100644 (file)
--- a/fs/btrfs/delayed-ref.h
+++ b/fs/btrfs/delayed-ref.h
@@ -245,6 +245,7 @@ struct btrfs_ref {
 #endif
        u64 bytenr;
        u64 len;
+       u64 owning_root;
 
        /* Bytenr of the parent tree block */
        u64 parent;
@@ -295,16 +296,18 @@ static inline u64 btrfs_calc_delayed_ref_csum_bytes(const struct btrfs_fs_info *
 }
 
 static inline void btrfs_init_generic_ref(struct btrfs_ref *generic_ref,
-                               int action, u64 bytenr, u64 len, u64 parent)
+                                         int action, u64 bytenr, u64 len,
+                                         u64 parent, u64 owning_root)
 {
        generic_ref->action = action;
        generic_ref->bytenr = bytenr;
        generic_ref->len = len;
        generic_ref->parent = parent;
+       generic_ref->owning_root = owning_root;
 }
 
-static inline void btrfs_init_tree_ref(struct btrfs_ref *generic_ref,
-                               int level, u64 root, u64 mod_root, bool skip_qgroup)
+static inline void btrfs_init_tree_ref(struct btrfs_ref *generic_ref, int level,
+                                      u64 root, u64 mod_root, bool skip_qgroup)
 {
 #ifdef CONFIG_BTRFS_FS_REF_VERIFY
        /* If @real_root not set, use @root as fallback */

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 52efc8e44cdb9dd829815840c3c22f9225211777..2dda3ecb49e6efd48b79c6d0e18d48e94e09389e 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2452,7 +2452,7 @@ static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
                        num_bytes = btrfs_file_extent_disk_num_bytes(buf, fi);
                        key.offset -= btrfs_file_extent_offset(buf, fi);
                        btrfs_init_generic_ref(&generic_ref, action, bytenr,
-                                              num_bytes, parent);
+                                              num_bytes, parent, ref_root);
                        btrfs_init_data_ref(&generic_ref, ref_root, key.objectid,
                                            key.offset, root->root_key.objectid,
                                            for_reloc);
@@ -2465,8 +2465,9 @@ static int __btrfs_mod_ref(struct btrfs_trans_handle *trans,
                } else {
                        bytenr = btrfs_node_blockptr(buf, i);
                        num_bytes = fs_info->nodesize;
+                       /* We don't know the owning_root, use 0. */
                        btrfs_init_generic_ref(&generic_ref, action, bytenr,
-                                              num_bytes, parent);
+                                              num_bytes, parent, 0);
                        btrfs_init_tree_ref(&generic_ref, level - 1, ref_root,
                                            root->root_key.objectid, for_reloc);
                        if (inc)
@@ -3289,7 +3290,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
        int ret;
 
        btrfs_init_generic_ref(&generic_ref, BTRFS_DROP_DELAYED_REF,
-                              buf->start, buf->len, parent);
+                              buf->start, buf->len, parent, btrfs_header_owner(buf));
        btrfs_init_tree_ref(&generic_ref, btrfs_header_level(buf),
                            root_id, 0, false);
 
@@ -4751,12 +4752,14 @@ int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
                                     struct btrfs_key *ins)
 {
        struct btrfs_ref generic_ref = { 0 };
+       u64 root_objectid = root->root_key.objectid;
+       u64 owning_root = root_objectid;
 
-       BUG_ON(root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID);
+       BUG_ON(root_objectid == BTRFS_TREE_LOG_OBJECTID);
 
        btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT,
-                              ins->objectid, ins->offset, 0);
-       btrfs_init_data_ref(&generic_ref, root->root_key.objectid, owner,
+                              ins->objectid, ins->offset, 0, owning_root);
+       btrfs_init_data_ref(&generic_ref, root_objectid, owner,
                            offset, 0, false);
        btrfs_ref_tree_mod(root->fs_info, &generic_ref);
 
@@ -4982,7 +4985,8 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
                extent_op->level = level;
 
                btrfs_init_generic_ref(&generic_ref, BTRFS_ADD_DELAYED_EXTENT,
-                                      ins.objectid, ins.offset, parent);
+                                      ins.objectid, ins.offset, parent,
+                                      btrfs_header_owner(buf));
                btrfs_init_tree_ref(&generic_ref, level, root_objectid,
                                    root->root_key.objectid, false);
                btrfs_ref_tree_mod(fs_info, &generic_ref);
@@ -5403,7 +5407,8 @@ skip:
                find_next_key(path, level, &wc->drop_progress);
 
                btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr,
-                                      fs_info->nodesize, parent);
+                                      fs_info->nodesize, parent,
+                                      btrfs_header_owner(next));
                btrfs_init_tree_ref(&ref, level - 1, root->root_key.objectid,
                                    0, false);
                ret = btrfs_free_extent(trans, &ref);

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 8065c8a3fe86246968a5db9dea33317b573e160d..bd9071e3e62b848f651df1f8240213afe2709d17 100644 (file)
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -374,7 +374,8 @@ next_slot:
                        if (update_refs && disk_bytenr > 0) {
                                btrfs_init_generic_ref(&ref,
                                                BTRFS_ADD_DELAYED_REF,
-                                               disk_bytenr, num_bytes, 0);
+                                               disk_bytenr, num_bytes, 0,
+                                               root->root_key.objectid);
                                btrfs_init_data_ref(&ref,
                                                root->root_key.objectid,
                                                new_key.objectid,
@@ -464,7 +465,8 @@ delete_extent_item:
                        } else if (update_refs && disk_bytenr > 0) {
                                btrfs_init_generic_ref(&ref,
                                                BTRFS_DROP_DELAYED_REF,
-                                               disk_bytenr, num_bytes, 0);
+                                               disk_bytenr, num_bytes, 0,
+                                               root->root_key.objectid);
                                btrfs_init_data_ref(&ref,
                                                root->root_key.objectid,
                                                key.objectid,
@@ -746,7 +748,7 @@ again:
                btrfs_mark_buffer_dirty(trans, leaf);
 
                btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, bytenr,
-                                      num_bytes, 0);
+                                      num_bytes, 0, root->root_key.objectid);
                btrfs_init_data_ref(&ref, root->root_key.objectid, ino,
                                    orig_offset, 0, false);
                ret = btrfs_inc_extent_ref(trans, &ref);
@@ -772,7 +774,7 @@ again:
        other_start = end;
        other_end = 0;
        btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr,
-                              num_bytes, 0);
+                              num_bytes, 0, root->root_key.objectid);
        btrfs_init_data_ref(&ref, root->root_key.objectid, ino, orig_offset,
                            0, false);
        if (extent_mergeable(leaf, path->slots[0] + 1,
@@ -2304,7 +2306,8 @@ static int btrfs_insert_replace_extent(struct btrfs_trans_handle *trans,
 
                btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF,
                                       extent_info->disk_offset,
-                                      extent_info->disk_len, 0);
+                                      extent_info->disk_len, 0,
+                                      root->root_key.objectid);
                ref_offset = extent_info->file_offset - extent_info->data_offset;
                btrfs_init_data_ref(&ref, root->root_key.objectid,
                                    btrfs_ino(inode), ref_offset, 0, false);

diff --git a/fs/btrfs/inode-item.c b/fs/btrfs/inode-item.c
index 143102ef1e54b40e7799c359aaf2d72f7c6130ae..7d734830e514ebac1dc7be390f738a0683e55bc4 100644 (file)
--- a/fs/btrfs/inode-item.c
+++ b/fs/btrfs/inode-item.c
@@ -676,7 +676,8 @@ delete:
                        bytes_deleted += extent_num_bytes;
 
                        btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF,
-                                       extent_start, extent_num_bytes, 0);
+                                       extent_start, extent_num_bytes, 0,
+                                       root->root_key.objectid);
                        btrfs_init_data_ref(&ref, btrfs_header_owner(leaf),
                                        control->ino, extent_offset,
                                        root->root_key.objectid, false);

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 3859724c9834535b96606bcdb0d6bd8b3fb84a5c..ce1db6152cc43fbcc2408f8bc08779b00cc47324 100644 (file)
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1158,7 +1158,7 @@ int replace_file_extents(struct btrfs_trans_handle *trans,
 
                key.offset -= btrfs_file_extent_offset(leaf, fi);
                btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr,
-                                      num_bytes, parent);
+                                      num_bytes, parent, root->root_key.objectid);
                btrfs_init_data_ref(&ref, btrfs_header_owner(leaf),
                                    key.objectid, key.offset,
                                    root->root_key.objectid, false);
@@ -1169,7 +1169,7 @@ int replace_file_extents(struct btrfs_trans_handle *trans,
                }
 
                btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr,
-                                      num_bytes, parent);
+                                      num_bytes, parent, root->root_key.objectid);
                btrfs_init_data_ref(&ref, btrfs_header_owner(leaf),
                                    key.objectid, key.offset,
                                    root->root_key.objectid, false);
@@ -1382,7 +1382,8 @@ again:
                btrfs_mark_buffer_dirty(trans, path->nodes[level]);
 
                btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, old_bytenr,
-                                      blocksize, path->nodes[level]->start);
+                                      blocksize, path->nodes[level]->start,
+                                      src->root_key.objectid);
                btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid,
                                    0, true);
                ret = btrfs_inc_extent_ref(trans, &ref);
@@ -1391,7 +1392,7 @@ again:
                        break;
                }
                btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr,
-                                      blocksize, 0);
+                                      blocksize, 0, dest->root_key.objectid);
                btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid, 0,
                                    true);
                ret = btrfs_inc_extent_ref(trans, &ref);
@@ -1400,8 +1401,9 @@ again:
                        break;
                }
 
+               /* We don't know the real owning_root, use 0. */
                btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, new_bytenr,
-                                      blocksize, path->nodes[level]->start);
+                                      blocksize, path->nodes[level]->start, 0);
                btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid,
                                    0, true);
                ret = btrfs_free_extent(trans, &ref);
@@ -1410,8 +1412,9 @@ again:
                        break;
                }
 
+               /* We don't know the real owning_root, use 0. */
                btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, old_bytenr,
-                                      blocksize, 0);
+                                      blocksize, 0, 0);
                btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid,
                                    0, true);
                ret = btrfs_free_extent(trans, &ref);
@@ -2520,7 +2523,8 @@ static int do_relocation(struct btrfs_trans_handle *trans,
 
                        btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF,
                                               node->eb->start, blocksize,
-                                              upper->eb->start);
+                                              upper->eb->start,
+                                              btrfs_header_owner(upper->eb));
                        btrfs_init_tree_ref(&ref, node->level,
                                            btrfs_header_owner(upper->eb),
                                            root->root_key.objectid, false);

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 5959824342161f432585f9427111f534a5d649d8..146f82e7147d5d9dd7285a214babc2de3a639e9f 100644 (file)
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -766,7 +766,8 @@ static noinline int replay_one_extent(struct btrfs_trans_handle *trans,
                        } else if (ret == 0) {
                                btrfs_init_generic_ref(&ref,
                                                BTRFS_ADD_DELAYED_REF,
-                                               ins.objectid, ins.offset, 0);
+                                               ins.objectid, ins.offset, 0,
+                                               root->root_key.objectid);
                                btrfs_init_data_ref(&ref,
                                                root->root_key.objectid,
                                                key->objectid, offset, 0, false);