Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752081AbdHHGfM (ORCPT ); Tue, 8 Aug 2017 02:35:12 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:2579 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751987AbdHHGfK (ORCPT ); Tue, 8 Aug 2017 02:35:10 -0400 Subject: Re: [PATCH] f2fs: fix some cases with reserved_blocks To: Chao Yu , , , CC: , , , , References: <1502165548-2023-1-git-send-email-yunlong.song@huawei.com> <5cf16cae-e6bd-13e8-7309-c975f5a27c96@huawei.com> From: Yunlong Song Message-ID: <0d7c0552-e9d6-ae17-6c9c-bf33b3a7d06d@huawei.com> Date: Tue, 8 Aug 2017 14:33:45 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <5cf16cae-e6bd-13e8-7309-c975f5a27c96@huawei.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.111.220.140] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020206.59895B90.00A3,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 64896a1e6f7f28c7432f1d6b90e3bc64 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2901 Lines: 79 Does this means the reserved_blocks cannot be used by users by can be used by filesystem? If it can be used by filesystem, then this cannot ensure the flash device really reserve the reserved_blocks space, right? The reserved_blocks is just for users? On 2017/8/8 14:08, Chao Yu wrote: > On 2017/8/8 12:12, Yunlong Song wrote: >> Signed-off-by: Yunlong Song >> --- >> fs/f2fs/recovery.c | 3 ++- >> fs/f2fs/super.c | 9 +++++---- >> 2 files changed, 7 insertions(+), 5 deletions(-) >> >> diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c >> index a3d0261..e288319 100644 >> --- a/fs/f2fs/recovery.c >> +++ b/fs/f2fs/recovery.c >> @@ -51,7 +51,8 @@ bool space_for_roll_forward(struct f2fs_sb_info *sbi) >> { >> s64 nalloc = percpu_counter_sum_positive(&sbi->alloc_valid_block_count); >> >> - if (sbi->last_valid_block_count + nalloc > sbi->user_block_count) >> + if (sbi->last_valid_block_count + nalloc + >> + sbi->reserved_blocks > sbi->user_block_count) > I think we can treat reserved blocks as over-provision space in f2fs, so it > would be safe to store invalid data (may become valid during recovery) there. > Anyway, it OK to remain old condition judgment. > >> return false; >> return true; >> } >> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c >> index 4c1bdcb..c644bf5 100644 >> --- a/fs/f2fs/super.c >> +++ b/fs/f2fs/super.c >> @@ -946,6 +946,7 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf) >> u64 id = huge_encode_dev(sb->s_bdev->bd_dev); >> block_t total_count, user_block_count, start_count, ovp_count; >> u64 avail_node_count; >> + block_t avail_user_block_count; >> >> total_count = le64_to_cpu(sbi->raw_super->block_count); >> user_block_count = sbi->user_block_count; >> @@ -953,16 +954,16 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf) >> ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg; >> buf->f_type = F2FS_SUPER_MAGIC; >> buf->f_bsize = sbi->blocksize; >> + avail_user_block_count = user_block_count - sbi->reserved_blocks; >> >> buf->f_blocks = total_count - start_count; >> buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count; >> - buf->f_bavail = user_block_count - valid_user_blocks(sbi) - >> - sbi->reserved_blocks; >> + buf->f_bavail = avail_user_block_count - valid_user_blocks(sbi); >> >> avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM; >> >> - if (avail_node_count > user_block_count) { >> - buf->f_files = user_block_count; >> + if (avail_node_count > avail_user_block_count) { > Likewise f_blocks calculation, the f_files one doesn't need to consider > reserved_blocks. > > Thanks, > >> + buf->f_files = avail_user_block_count; >> buf->f_ffree = buf->f_bavail; >> } else { >> buf->f_files = avail_node_count; >> > > . > -- Thanks, Yunlong Song