From patchwork Wed Sep 30 10:18:23 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chandan Rajendra X-Patchwork-Id: 7295581 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id CCD7CBEEA4 for ; Wed, 30 Sep 2015 10:20:15 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7B7252066B for ; Wed, 30 Sep 2015 10:20:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 53B0A2055D for ; Wed, 30 Sep 2015 10:20:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755931AbbI3KUI (ORCPT ); Wed, 30 Sep 2015 06:20:08 -0400 Received: from e28smtp05.in.ibm.com ([122.248.162.5]:39981 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932224AbbI3KUF (ORCPT ); Wed, 30 Sep 2015 06:20:05 -0400 Received: from /spool/local by e28smtp05.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 30 Sep 2015 15:50:03 +0530 Received: from d28dlp02.in.ibm.com (9.184.220.127) by e28smtp05.in.ibm.com (192.168.1.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Wed, 30 Sep 2015 15:50:01 +0530 X-Helo: d28dlp02.in.ibm.com X-MailFrom: chandan@linux.vnet.ibm.com X-RcptTo: linux-btrfs@vger.kernel.org Received: from d28relay03.in.ibm.com (d28relay03.in.ibm.com [9.184.220.60]) by d28dlp02.in.ibm.com (Postfix) with ESMTP id 26BC23940064 for ; Wed, 30 Sep 2015 15:50:00 +0530 (IST) Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay03.in.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t8UAJwlQ12451906 for ; Wed, 30 Sep 2015 15:49:59 +0530 Received: from d28av04.in.ibm.com (localhost [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t8UAImar011990 for ; Wed, 30 Sep 2015 15:48:50 +0530 Received: from localhost.in.ibm.com ([9.124.35.170]) by d28av04.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id t8UAIklb011707; Wed, 30 Sep 2015 15:48:48 +0530 From: Chandan Rajendra To: linux-btrfs@vger.kernel.org Cc: Chandan Rajendra , jbacik@fb.com, clm@fb.com, bo.li.liu@oracle.com, dsterba@suse.cz, quwenruo@cn.fujitsu.com, chandan@mykolab.com Subject: [RFC PATCH V4 07/13] Btrfs: Use (eb->start, seq) as search key for tree modification log Date: Wed, 30 Sep 2015 15:48:23 +0530 Message-Id: <1443608309-30154-8-git-send-email-chandan@linux.vnet.ibm.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1443608309-30154-1-git-send-email-chandan@linux.vnet.ibm.com> References: <1443608309-30154-1-git-send-email-chandan@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15093010-0017-0000-0000-00000786B7A6 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In subpagesize-blocksize a page can map multiple extent buffers and hence using (page index, seq) as the search key is incorrect. For example, searching through tree modification log tree can return an entry associated with the first extent buffer mapped by the page (if such an entry exists), when we are actually searching for entries associated with extent buffers that are mapped at position 2 or more in the page. Reviewed-by: Liu Bo Signed-off-by: Chandan Rajendra --- fs/btrfs/ctree.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 5f745ea..719ed3c 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -311,7 +311,7 @@ struct tree_mod_root { struct tree_mod_elem { struct rb_node node; - u64 index; /* shifted logical */ + u64 logical; u64 seq; enum mod_log_op op; @@ -435,11 +435,11 @@ void btrfs_put_tree_mod_seq(struct btrfs_fs_info *fs_info, /* * key order of the log: - * index -> sequence + * node/leaf start address -> sequence * - * the index is the shifted logical of the *new* root node for root replace - * operations, or the shifted logical of the affected block for all other - * operations. + * The 'start address' is the logical address of the *new* root node + * for root replace operations, or the logical address of the affected + * block for all other operations. * * Note: must be called with write lock (tree_mod_log_write_lock). */ @@ -460,9 +460,9 @@ __tree_mod_log_insert(struct btrfs_fs_info *fs_info, struct tree_mod_elem *tm) while (*new) { cur = container_of(*new, struct tree_mod_elem, node); parent = *new; - if (cur->index < tm->index) + if (cur->logical < tm->logical) new = &((*new)->rb_left); - else if (cur->index > tm->index) + else if (cur->logical > tm->logical) new = &((*new)->rb_right); else if (cur->seq < tm->seq) new = &((*new)->rb_left); @@ -523,7 +523,7 @@ alloc_tree_mod_elem(struct extent_buffer *eb, int slot, if (!tm) return NULL; - tm->index = eb->start >> PAGE_CACHE_SHIFT; + tm->logical = eb->start; if (op != MOD_LOG_KEY_ADD) { btrfs_node_key(eb, &tm->key, slot); tm->blockptr = btrfs_node_blockptr(eb, slot); @@ -588,7 +588,7 @@ tree_mod_log_insert_move(struct btrfs_fs_info *fs_info, goto free_tms; } - tm->index = eb->start >> PAGE_CACHE_SHIFT; + tm->logical = eb->start; tm->slot = src_slot; tm->move.dst_slot = dst_slot; tm->move.nr_items = nr_items; @@ -699,7 +699,7 @@ tree_mod_log_insert_root(struct btrfs_fs_info *fs_info, goto free_tms; } - tm->index = new_root->start >> PAGE_CACHE_SHIFT; + tm->logical = new_root->start; tm->old_root.logical = old_root->start; tm->old_root.level = btrfs_header_level(old_root); tm->generation = btrfs_header_generation(old_root); @@ -739,16 +739,15 @@ __tree_mod_log_search(struct btrfs_fs_info *fs_info, u64 start, u64 min_seq, struct rb_node *node; struct tree_mod_elem *cur = NULL; struct tree_mod_elem *found = NULL; - u64 index = start >> PAGE_CACHE_SHIFT; tree_mod_log_read_lock(fs_info); tm_root = &fs_info->tree_mod_log; node = tm_root->rb_node; while (node) { cur = container_of(node, struct tree_mod_elem, node); - if (cur->index < index) { + if (cur->logical < start) { node = node->rb_left; - } else if (cur->index > index) { + } else if (cur->logical > start) { node = node->rb_right; } else if (cur->seq < min_seq) { node = node->rb_left; @@ -1230,9 +1229,10 @@ __tree_mod_log_oldest_root(struct btrfs_fs_info *fs_info, return NULL; /* - * the very last operation that's logged for a root is the replacement - * operation (if it is replaced at all). this has the index of the *new* - * root, making it the very first operation that's logged for this root. + * the very last operation that's logged for a root is the + * replacement operation (if it is replaced at all). this has + * the logical address of the *new* root, making it the very + * first operation that's logged for this root. */ while (1) { tm = tree_mod_log_search_oldest(fs_info, root_logical, @@ -1336,7 +1336,7 @@ __tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb, if (!next) break; tm = container_of(next, struct tree_mod_elem, node); - if (tm->index != first_tm->index) + if (tm->logical != first_tm->logical) break; } tree_mod_log_read_unlock(fs_info);