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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 AA6B2C4360F for ; Thu, 4 Apr 2019 08:49:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 716ED217D4 for ; Thu, 4 Apr 2019 08:49:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554367796; bh=jItkgQt/kKflLl0PAR5WinIoJot+r5yLBxoil5ETJbY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1e2C9ZJmzzEln75S8ORyc1elGjAGRmF3cakYLpRjnrwo2yTEPL5IkxIiFEAT5x7QW lPidGlo7NR5sndiucLolhj5imDdFLNACt+DCNU+lmrucT+yV3EXWC664HjL4vn4SeL dxGmuGpo7CO8lTlHXd/ZNmAVEA9ZcQyMxqaiUqBc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728813AbfDDIty (ORCPT ); Thu, 4 Apr 2019 04:49:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:50674 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728843AbfDDItw (ORCPT ); Thu, 4 Apr 2019 04:49:52 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CC8722171F; Thu, 4 Apr 2019 08:49:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554367791; bh=jItkgQt/kKflLl0PAR5WinIoJot+r5yLBxoil5ETJbY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pgC4yC7Yxx27GdHbUcoabUaAsW/ITWGwAnKv2PO7QlYmiAanAPWApiPddgQaeQmFV O86yRKoB18zBJgrqpO/I2VYFWQgivvCRHbMIV/691nUlKiGQzykI3l20CSb3rB9eYh Gna2g8oa1lHOZFYhN/4GD9cUCNCCzYdoMr0YLaPE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "zhangyi (F)" , Theodore Tso , Jan Kara , Jari Ruusu Subject: [PATCH 4.9 03/91] ext4: cleanup bh release code in ext4_ind_remove_space() Date: Thu, 4 Apr 2019 10:46:47 +0200 Message-Id: <20190404084535.624035856@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190404084535.450029272@linuxfoundation.org> References: <20190404084535.450029272@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: zhangyi (F) commit 5e86bdda41534e17621d5a071b294943cae4376e upstream. Currently, we are releasing the indirect buffer where we are done with it in ext4_ind_remove_space(), so we can see the brelse() and BUFFER_TRACE() everywhere. It seems fragile and hard to read, and we may probably forget to release the buffer some day. This patch cleans up the code by putting of the code which releases the buffers to the end of the function. Signed-off-by: zhangyi (F) Signed-off-by: Theodore Ts'o Reviewed-by: Jan Kara Cc: Jari Ruusu Signed-off-by: Greg Kroah-Hartman --- fs/ext4/indirect.c | 47 ++++++++++++++++++++++------------------------- 1 file changed, 22 insertions(+), 25 deletions(-) --- a/fs/ext4/indirect.c +++ b/fs/ext4/indirect.c @@ -1217,6 +1217,7 @@ int ext4_ind_remove_space(handle_t *hand ext4_lblk_t offsets[4], offsets2[4]; Indirect chain[4], chain2[4]; Indirect *partial, *partial2; + Indirect *p = NULL, *p2 = NULL; ext4_lblk_t max_block; __le32 nr = 0, nr2 = 0; int n = 0, n2 = 0; @@ -1258,7 +1259,7 @@ int ext4_ind_remove_space(handle_t *hand } - partial = ext4_find_shared(inode, n, offsets, chain, &nr); + partial = p = ext4_find_shared(inode, n, offsets, chain, &nr); if (nr) { if (partial == chain) { /* Shared branch grows from the inode */ @@ -1283,13 +1284,11 @@ int ext4_ind_remove_space(handle_t *hand partial->p + 1, (__le32 *)partial->bh->b_data+addr_per_block, (chain+n-1) - partial); - BUFFER_TRACE(partial->bh, "call brelse"); - brelse(partial->bh); partial--; } end_range: - partial2 = ext4_find_shared(inode, n2, offsets2, chain2, &nr2); + partial2 = p2 = ext4_find_shared(inode, n2, offsets2, chain2, &nr2); if (nr2) { if (partial2 == chain2) { /* @@ -1319,16 +1318,14 @@ end_range: (__le32 *)partial2->bh->b_data, partial2->p, (chain2+n2-1) - partial2); - BUFFER_TRACE(partial2->bh, "call brelse"); - brelse(partial2->bh); partial2--; } goto do_indirects; } /* Punch happened within the same level (n == n2) */ - partial = ext4_find_shared(inode, n, offsets, chain, &nr); - partial2 = ext4_find_shared(inode, n2, offsets2, chain2, &nr2); + partial = p = ext4_find_shared(inode, n, offsets, chain, &nr); + partial2 = p2 = ext4_find_shared(inode, n2, offsets2, chain2, &nr2); /* Free top, but only if partial2 isn't its subtree. */ if (nr) { @@ -1385,15 +1382,7 @@ end_range: partial->p + 1, partial2->p, (chain+n-1) - partial); - while (partial > chain) { - BUFFER_TRACE(partial->bh, "call brelse"); - brelse(partial->bh); - } - while (partial2 > chain2) { - BUFFER_TRACE(partial2->bh, "call brelse"); - brelse(partial2->bh); - } - return 0; + goto cleanup; } /* @@ -1408,8 +1397,6 @@ end_range: partial->p + 1, (__le32 *)partial->bh->b_data+addr_per_block, (chain+n-1) - partial); - BUFFER_TRACE(partial->bh, "call brelse"); - brelse(partial->bh); partial--; } if (partial2 > chain2 && depth2 <= depth) { @@ -1417,11 +1404,21 @@ end_range: (__le32 *)partial2->bh->b_data, partial2->p, (chain2+n2-1) - partial2); - BUFFER_TRACE(partial2->bh, "call brelse"); - brelse(partial2->bh); partial2--; } } + +cleanup: + while (p && p > chain) { + BUFFER_TRACE(p->bh, "call brelse"); + brelse(p->bh); + p--; + } + while (p2 && p2 > chain2) { + BUFFER_TRACE(p2->bh, "call brelse"); + brelse(p2->bh); + p2--; + } return 0; do_indirects: @@ -1429,7 +1426,7 @@ do_indirects: switch (offsets[0]) { default: if (++n >= n2) - return 0; + break; nr = i_data[EXT4_IND_BLOCK]; if (nr) { ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1); @@ -1437,7 +1434,7 @@ do_indirects: } case EXT4_IND_BLOCK: if (++n >= n2) - return 0; + break; nr = i_data[EXT4_DIND_BLOCK]; if (nr) { ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2); @@ -1445,7 +1442,7 @@ do_indirects: } case EXT4_DIND_BLOCK: if (++n >= n2) - return 0; + break; nr = i_data[EXT4_TIND_BLOCK]; if (nr) { ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3); @@ -1454,5 +1451,5 @@ do_indirects: case EXT4_TIND_BLOCK: ; } - return 0; + goto cleanup; }