From: Kazuya Mio Subject: [PATCH v3 07/11] e4defrag: Allow user who can use reserved blocks to defrag Date: Mon, 14 Nov 2011 15:24:49 +0900 Message-ID: <4EC0B431.20802@sx.jp.nec.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Cc: Theodore Tso , Andreas Dilger To: ext4 Return-path: Received: from TYO200.gate.nec.co.jp ([202.32.8.215]:51595 "EHLO tyo200.gate.nec.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752007Ab1KNGiI (ORCPT ); Mon, 14 Nov 2011 01:38:08 -0500 Received: from tyo202.gate.nec.co.jp ([10.7.69.202]) by tyo200.gate.nec.co.jp (8.13.8/8.13.4) with ESMTP id pAE6c6MU024500 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Mon, 14 Nov 2011 15:38:06 +0900 (JST) Sender: linux-ext4-owner@vger.kernel.org List-ID: Fix free blocks check for general users to use the reserved blocks because they can use reserved blocks in the following cases: - the users are specified by mount option resuid/resgid - e4defrag has CAP_SYS_RESOURCE capability Signed-off-by: Kazuya Mio --- misc/e4defrag.c | 37 +++++++------------------------------ 1 file changed, 7 insertions(+), 30 deletions(-) diff --git a/misc/e4defrag.c b/misc/e4defrag.c index effd774..45e9b72 100644 --- a/misc/e4defrag.c +++ b/misc/e4defrag.c @@ -471,12 +471,15 @@ static int defrag_fadvise(int fd, struct move_extent defrag_data, * @fd: defrag target file's descriptor. * @file: file name. * @blk_count: file blocks. + * + * Note that the users who cannot use the reserved blocks might pass this + * free space check though there is no free blocks except for reserved blocks. + * In this case, they can catch ENOSPC when donor file is created by fallocate + * in file_defrag(). So, it's no problem. */ static int check_free_size(int fd, const char *file, ext4_fsblk_t blk_count) { - ext4_fsblk_t free_blk_count; struct statfs64 fsbuf; - uid_t current_uid = getuid(); if (fstatfs64(fd, &fsbuf) < 0) { if (mode_flag & DETAIL) { @@ -487,16 +490,7 @@ static int check_free_size(int fd, const char *file, ext4_fsblk_t blk_count) return -1; } - /* Compute free space for root and normal user separately */ - if (current_uid == ROOT_UID) - free_blk_count = fsbuf.f_bfree; - else - free_blk_count = fsbuf.f_bavail; - - if (free_blk_count >= blk_count) - return 0; - - return -ENOSPC; + return (fsbuf.f_bfree >= blk_count) ? 0 : -ENOSPC; } /* @@ -768,23 +762,6 @@ static int get_exts_count(struct fiemap_extent_list *ext_list_head) return ret; } -/* get_file_blocks() - Get total file blocks. - * - * @ext_list_head: the extent list head of the target file - */ -static ext4_fsblk_t get_file_blocks(struct fiemap_extent_list *ext_list_head) -{ - ext4_fsblk_t blk_count = 0; - struct fiemap_extent_list *ext_list_tmp = ext_list_head; - - do { - blk_count += ext_list_tmp->data.len; - ext_list_tmp = ext_list_tmp->next; - } while (ext_list_tmp != ext_list_head); - - return blk_count; -}