From patchwork Fri Sep 6 17:15:32 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Fasheh X-Patchwork-Id: 11135747 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8F8C114ED for ; Fri, 6 Sep 2019 17:16:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 791C12082C for ; Fri, 6 Sep 2019 17:16:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404411AbfIFRQH (ORCPT ); Fri, 6 Sep 2019 13:16:07 -0400 Received: from mx2.suse.de ([195.135.220.15]:36564 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2404350AbfIFRQH (ORCPT ); Fri, 6 Sep 2019 13:16:07 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 59BBFADDA for ; Fri, 6 Sep 2019 17:16:05 +0000 (UTC) From: Mark Fasheh To: linux-btrfs@vger.kernel.org Cc: Mark Fasheh Subject: [PATCH 2/3] btrfs: move ref finding machinery out of build_backref_tree() Date: Fri, 6 Sep 2019 10:15:32 -0700 Message-Id: <20190906171533.618-3-mfasheh@suse.com> X-Mailer: git-send-email 2.22.1 In-Reply-To: <20190906171533.618-1-mfasheh@suse.com> References: <20190906171533.618-1-mfasheh@suse.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Mark Fasheh build_backref_tree() is walking extent refs in what is an otherwise self contained chunk of code. We can shrink the total number of lines in build_backref_tree() *and* make it more readable by moving that walk into its own subroutine. Signed-off-by: Mark Fasheh Reviewed-by: Josef Bacik --- fs/btrfs/backref-cache.c | 110 +++++++++++++++++++++++---------------- 1 file changed, 65 insertions(+), 45 deletions(-) diff --git a/fs/btrfs/backref-cache.c b/fs/btrfs/backref-cache.c index d0f6530f23b8..ff0d49ca6e26 100644 --- a/fs/btrfs/backref-cache.c +++ b/fs/btrfs/backref-cache.c @@ -336,6 +336,61 @@ int find_inline_backref(struct extent_buffer *leaf, int slot, return 0; } +#define SEARCH_COMPLETE 1 +#define SEARCH_NEXT 2 +static int find_next_ref(struct btrfs_root *extent_root, u64 cur_bytenr, + struct btrfs_path *path, unsigned long *ptr, + unsigned long *end, struct btrfs_key *key, bool exist) +{ + struct extent_buffer *eb = path->nodes[0]; + int ret; + + if (*ptr >= *end) { + if (path->slots[0] >= btrfs_header_nritems(eb)) { + ret = btrfs_next_leaf(extent_root, path); + if (ret < 0) + goto out; + if (ret > 0) + return SEARCH_COMPLETE; + eb = path->nodes[0]; + } + + btrfs_item_key_to_cpu(eb, key, path->slots[0]); + if (key->objectid != cur_bytenr) { + WARN_ON(exist); + return SEARCH_COMPLETE; + } + + if (key->type == BTRFS_EXTENT_ITEM_KEY || + key->type == BTRFS_METADATA_ITEM_KEY) { + ret = find_inline_backref(eb, path->slots[0], + ptr, end); + if (ret) + return SEARCH_NEXT; + } + } + + if (*ptr < *end) { + /* update key for inline back ref */ + struct btrfs_extent_inline_ref *iref; + int type; + iref = (struct btrfs_extent_inline_ref *)(*ptr); + type = btrfs_get_extent_inline_ref_type(eb, iref, + BTRFS_REF_TYPE_BLOCK); + if (type == BTRFS_REF_TYPE_INVALID) { + ret = -EUCLEAN; + goto out; + } + key->type = type; + key->offset = btrfs_extent_inline_ref_offset(eb, iref); + + WARN_ON(key->type != BTRFS_TREE_BLOCK_REF_KEY && + key->type != BTRFS_SHARED_BLOCK_REF_KEY); + } + ret = 0; +out: + return ret; +} /* * build backref tree for a given tree block. root of the backref tree @@ -439,52 +494,17 @@ struct backref_node *build_backref_tree(struct reloc_control *rc, while (1) { cond_resched(); - eb = path1->nodes[0]; - - if (ptr >= end) { - if (path1->slots[0] >= btrfs_header_nritems(eb)) { - ret = btrfs_next_leaf(rc->extent_root, path1); - if (ret < 0) { - err = ret; - goto out; - } - if (ret > 0) - break; - eb = path1->nodes[0]; - } - - btrfs_item_key_to_cpu(eb, &key, path1->slots[0]); - if (key.objectid != cur->bytenr) { - WARN_ON(exist); - break; - } - - if (key.type == BTRFS_EXTENT_ITEM_KEY || - key.type == BTRFS_METADATA_ITEM_KEY) { - ret = find_inline_backref(eb, path1->slots[0], - &ptr, &end); - if (ret) - goto next; - } - } - - if (ptr < end) { - /* update key for inline back ref */ - struct btrfs_extent_inline_ref *iref; - int type; - iref = (struct btrfs_extent_inline_ref *)ptr; - type = btrfs_get_extent_inline_ref_type(eb, iref, - BTRFS_REF_TYPE_BLOCK); - if (type == BTRFS_REF_TYPE_INVALID) { - err = -EUCLEAN; - goto out; - } - key.type = type; - key.offset = btrfs_extent_inline_ref_offset(eb, iref); - - WARN_ON(key.type != BTRFS_TREE_BLOCK_REF_KEY && - key.type != BTRFS_SHARED_BLOCK_REF_KEY); + ret = find_next_ref(rc->extent_root, cur->bytenr, path1, &ptr, + &end, &key, exist != NULL); + if (ret < 0) { + err = ret; + goto out; } + eb = path1->nodes[0]; + if (ret == SEARCH_COMPLETE) + break; + else if (ret == SEARCH_NEXT) + goto next; /* * Parent node found and matches current inline ref, no need to