From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B901C43331 for ; Thu, 26 Mar 2020 08:33:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2E38520772 for ; Thu, 26 Mar 2020 08:33:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727575AbgCZId1 (ORCPT ); Thu, 26 Mar 2020 04:33:27 -0400 Received: from mx2.suse.de ([195.135.220.15]:48976 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726210AbgCZId1 (ORCPT ); Thu, 26 Mar 2020 04:33:27 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id F0742AD08; Thu, 26 Mar 2020 08:33:24 +0000 (UTC) From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: Johannes Thumshirn , Josef Bacik Subject: [PATCH v2 02/39] btrfs: backref: Implement btrfs_backref_iter_next() Date: Thu, 26 Mar 2020 16:32:39 +0800 Message-Id: <20200326083316.48847-3-wqu@suse.com> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200326083316.48847-1-wqu@suse.com> References: <20200326083316.48847-1-wqu@suse.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This function will go next inline/keyed backref for btrfs_backref_iter infrastructure. Signed-off-by: Qu Wenruo Reviewed-by: Johannes Thumshirn Reviewed-by: Josef Bacik --- fs/btrfs/backref.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/backref.h | 34 +++++++++++++++++++++++++++ 2 files changed, 92 insertions(+) diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index b27e90e362d6..a1044f093f6c 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -2405,3 +2405,61 @@ int btrfs_backref_iter_start(struct btrfs_backref_iter *iter, u64 bytenr) btrfs_backref_iter_release(iter); return ret; } + +/* + * Go to next backref item of current bytenr, can be either inlined or keyed. + * + * Caller need to check whether it's inline ref or not by iter->cur_key. + * + * Return 0 if we get next backref without problem. + * Return >0 if there is no extra backref for this bytenr. + * Return <0 if there is something wrong happened. + */ +int btrfs_backref_iter_next(struct btrfs_backref_iter *iter) +{ + struct extent_buffer *eb = btrfs_backref_get_eb(iter); + struct btrfs_path *path = iter->path; + struct btrfs_extent_inline_ref *iref; + int ret; + u32 size; + + if (btrfs_backref_iter_is_inline_ref(iter)) { + /* We're still inside the inline refs */ + ASSERT(iter->cur_ptr < iter->end_ptr); + + if (btrfs_backref_has_tree_block_info(iter)) { + /* First tree block info */ + size = sizeof(struct btrfs_tree_block_info); + } else { + /* Use inline ref type to determine the size */ + int type; + + iref = (struct btrfs_extent_inline_ref *) + ((unsigned long)iter->cur_ptr); + type = btrfs_extent_inline_ref_type(eb, iref); + + size = btrfs_extent_inline_ref_size(type); + } + iter->cur_ptr += size; + if (iter->cur_ptr < iter->end_ptr) + return 0; + + /* All inline items iterated, fall through */ + } + /* We're at keyed items, there is no inline item, just go next item */ + ret = btrfs_next_item(iter->fs_info->extent_root, iter->path); + if (ret) + return ret; + + btrfs_item_key_to_cpu(path->nodes[0], &iter->cur_key, path->slots[0]); + if (iter->cur_key.objectid != iter->bytenr || + (iter->cur_key.type != BTRFS_TREE_BLOCK_REF_KEY && + iter->cur_key.type != BTRFS_SHARED_BLOCK_REF_KEY)) + return 1; + iter->item_ptr = (u32)btrfs_item_ptr_offset(path->nodes[0], + path->slots[0]); + iter->cur_ptr = iter->item_ptr; + iter->end_ptr = iter->item_ptr + (u32)btrfs_item_size_nr(path->nodes[0], + path->slots[0]); + return 0; +} diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h index 4217e9019f4a..3226dea35e2c 100644 --- a/fs/btrfs/backref.h +++ b/fs/btrfs/backref.h @@ -104,8 +104,42 @@ static inline void btrfs_backref_iter_free(struct btrfs_backref_iter *iter) kfree(iter); } +static inline struct extent_buffer * +btrfs_backref_get_eb(struct btrfs_backref_iter *iter) +{ + if (!iter) + return NULL; + return iter->path->nodes[0]; +} + +/* + * For metadata with EXTENT_ITEM key (non-skinny) case, the first inline data + * is btrfs_tree_block_info, without a btrfs_extent_inline_ref header. + * + * This helper is here to determine if that's the case. + */ +static inline bool btrfs_backref_has_tree_block_info( + struct btrfs_backref_iter *iter) +{ + if (iter->cur_key.type == BTRFS_EXTENT_ITEM_KEY && + iter->cur_ptr - iter->item_ptr == sizeof(struct btrfs_extent_item)) + return true; + return false; +} + int btrfs_backref_iter_start(struct btrfs_backref_iter *iter, u64 bytenr); +int btrfs_backref_iter_next(struct btrfs_backref_iter *iter); + +static inline bool +btrfs_backref_iter_is_inline_ref(struct btrfs_backref_iter *iter) +{ + if (iter->cur_key.type == BTRFS_EXTENT_ITEM_KEY || + iter->cur_key.type == BTRFS_METADATA_ITEM_KEY) + return true; + return false; +} + static inline void btrfs_backref_iter_release(struct btrfs_backref_iter *iter) { -- 2.26.0