diff options
| -rw-r--r-- | fs/btrfs/backref.c | 35 | ||||
| -rw-r--r-- | fs/btrfs/backref.h | 9 | ||||
| -rw-r--r-- | fs/btrfs/send.c | 33 |
3 files changed, 63 insertions, 14 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 33056c4c0528..430974cf3b96 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -1111,10 +1111,12 @@ static int add_inline_refs(struct btrfs_backref_walk_ctx *ctx, root = btrfs_extent_data_ref_root(leaf, dref); - ret = add_indirect_ref(ctx->fs_info, preftrees, root, - &key, 0, ctx->bytenr, count, - sc, GFP_NOFS); - + if (!ctx->skip_data_ref || + !ctx->skip_data_ref(root, key.objectid, key.offset, + ctx->user_ctx)) + ret = add_indirect_ref(ctx->fs_info, preftrees, + root, &key, 0, ctx->bytenr, + count, sc, GFP_NOFS); break; } default: @@ -1133,8 +1135,9 @@ static int add_inline_refs(struct btrfs_backref_walk_ctx *ctx, * * Returns 0 on success, <0 on error, or BACKREF_FOUND_SHARED. */ -static int add_keyed_refs(struct btrfs_root *extent_root, - struct btrfs_path *path, u64 bytenr, +static int add_keyed_refs(struct btrfs_backref_walk_ctx *ctx, + struct btrfs_root *extent_root, + struct btrfs_path *path, int info_level, struct preftrees *preftrees, struct share_check *sc) { @@ -1157,7 +1160,7 @@ static int add_keyed_refs(struct btrfs_root *extent_root, leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, slot); - if (key.objectid != bytenr) + if (key.objectid != ctx->bytenr) break; if (key.type < BTRFS_TREE_BLOCK_REF_KEY) continue; @@ -1169,7 +1172,7 @@ static int add_keyed_refs(struct btrfs_root *extent_root, /* SHARED DIRECT METADATA backref */ ret = add_direct_ref(fs_info, preftrees, info_level + 1, key.offset, - bytenr, 1, NULL, GFP_NOFS); + ctx->bytenr, 1, NULL, GFP_NOFS); break; case BTRFS_SHARED_DATA_REF_KEY: { /* SHARED DIRECT FULL backref */ @@ -1180,14 +1183,14 @@ static int add_keyed_refs(struct btrfs_root *extent_root, struct btrfs_shared_data_ref); count = btrfs_shared_data_ref_count(leaf, sdref); ret = add_direct_ref(fs_info, preftrees, 0, - key.offset, bytenr, count, + key.offset, ctx->bytenr, count, sc, GFP_NOFS); break; } case BTRFS_TREE_BLOCK_REF_KEY: /* NORMAL INDIRECT METADATA backref */ ret = add_indirect_ref(fs_info, preftrees, key.offset, - NULL, info_level + 1, bytenr, + NULL, info_level + 1, ctx->bytenr, 1, NULL, GFP_NOFS); break; case BTRFS_EXTENT_DATA_REF_KEY: { @@ -1211,9 +1214,13 @@ static int add_keyed_refs(struct btrfs_root *extent_root, } root = btrfs_extent_data_ref_root(leaf, dref); - ret = add_indirect_ref(fs_info, preftrees, root, - &key, 0, bytenr, count, - sc, GFP_NOFS); + + if (!ctx->skip_data_ref || + !ctx->skip_data_ref(root, key.objectid, key.offset, + ctx->user_ctx)) + ret = add_indirect_ref(fs_info, preftrees, root, + &key, 0, ctx->bytenr, + count, sc, GFP_NOFS); break; } default: @@ -1466,7 +1473,7 @@ again: &preftrees, sc); if (ret) goto out; - ret = add_keyed_refs(root, path, ctx->bytenr, info_level, + ret = add_keyed_refs(ctx, root, path, info_level, &preftrees, sc); if (ret) goto out; diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h index 1bd5a15c7f9e..ef6bbea3f456 100644 --- a/fs/btrfs/backref.h +++ b/fs/btrfs/backref.h @@ -116,6 +116,15 @@ struct btrfs_backref_walk_ctx { */ int (*check_extent_item)(u64 bytenr, const struct btrfs_extent_item *ei, const struct extent_buffer *leaf, void *user_ctx); + /* + * If this is not NULL, then the backref walking code will call this for + * each extent data ref it finds (BTRFS_EXTENT_DATA_REF_KEY keys) before + * processing that data ref. If this callback return false, then it will + * ignore this data ref and it will never resolve the indirect data ref, + * saving time searching for leaves in a fs tree with file extent items + * matching the data ref. + */ + bool (*skip_data_ref)(u64 root, u64 ino, u64 offset, void *user_ctx); /* Context object to pass to the callbacks defined above. */ void *user_ctx; }; diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 516b80637bfb..383bc8a5cb6c 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -1284,6 +1284,10 @@ struct backref_ctx { /* The bytenr the file extent item we are processing refers to. */ u64 bytenr; + /* The owner (root id) of the data backref for the current extent. */ + u64 backref_owner; + /* The offset of the data backref for the current extent. */ + u64 backref_offset; }; static int __clone_root_cmp_bsearch(const void *key, const void *elt) @@ -1558,6 +1562,18 @@ static int check_extent_item(u64 bytenr, const struct btrfs_extent_item *ei, return 0; } +static bool skip_self_data_ref(u64 root, u64 ino, u64 offset, void *ctx) +{ + const struct backref_ctx *bctx = ctx; + + if (ino == bctx->cur_objectid && + root == bctx->backref_owner && + offset == bctx->backref_offset) + return true; + + return false; +} + /* * Given an inode, offset and extent item, it finds a good clone for a clone * instruction. Returns -ENOENT when none could be found. The function makes @@ -1624,6 +1640,12 @@ static int find_extent_clone(struct send_ctx *sctx, backref_ctx.cur_objectid = ino; backref_ctx.cur_offset = data_offset; backref_ctx.bytenr = disk_byte; + /* + * Use the header owner and not the send root's id, because in case of a + * snapshot we can have shared subtrees. + */ + backref_ctx.backref_owner = btrfs_header_owner(eb); + backref_ctx.backref_offset = data_offset - btrfs_file_extent_offset(eb, fi); /* * The last extent of a file may be too large due to page alignment. @@ -1648,6 +1670,17 @@ static int find_extent_clone(struct send_ctx *sctx, backref_walk_ctx.check_extent_item = check_extent_item; backref_walk_ctx.user_ctx = &backref_ctx; + /* + * If have a single clone root, then it's the send root and we can tell + * the backref walking code to skip our own backref and not resolve it, + * since we can not use it for cloning - the source and destination + * ranges can't overlap and in case the leaf is shared through a subtree + * due to snapshots, we can't use those other roots since they are not + * in the list of clone roots. + */ + if (sctx->clone_roots_cnt == 1) + backref_walk_ctx.skip_data_ref = skip_self_data_ref; + ret = iterate_extent_inodes(&backref_walk_ctx, true, iterate_backrefs, &backref_ctx); if (ret < 0) |