From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751631AbdK1Gvx (ORCPT ); Tue, 28 Nov 2017 01:51:53 -0500 Received: from mail-oi0-f67.google.com ([209.85.218.67]:36237 "EHLO mail-oi0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751256AbdK1Gvv (ORCPT ); Tue, 28 Nov 2017 01:51:51 -0500 X-Google-Smtp-Source: AGs4zMbB7nOZS/5CPTsDIJnxIJcRb0Be5cts9T+GkxoCGY3DGg3NYblTA+9td56pxyZEQYTzueO/aA== Subject: Re: [Ocfs2-devel] [PATCH 2/3] ocfs2: add ocfs2_overwrite_io function To: Gang He , jlbec@evilplan.org, hch@lst.de, Goldwyn Rodrigues , mfasheh@versity.com Cc: ocfs2-devel@oss.oracle.com, linux-kernel@vger.kernel.org References: <1511775987-841-1-git-send-email-ghe@suse.com> <1511775987-841-3-git-send-email-ghe@suse.com> <123f1322-d453-4aca-ac95-63d6f90fd8a2@gmail.com> <5A1D49E5020000F90009AC66@prv-mh.provo.novell.com> From: Joseph Qi Message-ID: <805fb849-dcc7-cbbc-02af-1c6116a88957@gmail.com> Date: Tue, 28 Nov 2017 14:51:45 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: <5A1D49E5020000F90009AC66@prv-mh.provo.novell.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 17/11/28 11:35, Gang He wrote: > Hello Joseph, > > >>>> >> Hi Gang, >> >> On 17/11/27 17:46, Gang He wrote: >>> Add ocfs2_overwrite_io function, which is used to judge if >>> overwrite allocated blocks, otherwise, the write will bring extra >>> block allocation overhead. >>> >>> Signed-off-by: Gang He >>> --- >>> fs/ocfs2/extent_map.c | 67 >> +++++++++++++++++++++++++++++++++++++++++++++++++++ >>> fs/ocfs2/extent_map.h | 3 +++ >>> 2 files changed, 70 insertions(+) >>> >>> diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c >>> index e4719e0..98bf325 100644 >>> --- a/fs/ocfs2/extent_map.c >>> +++ b/fs/ocfs2/extent_map.c >>> @@ -832,6 +832,73 @@ int ocfs2_fiemap(struct inode *inode, struct >> fiemap_extent_info *fieinfo, >>> return ret; >>> } >>> >>> +/* Is IO overwriting allocated blocks? */ >>> +int ocfs2_overwrite_io(struct inode *inode, u64 map_start, u64 map_len, >>> + int wait) >>> +{ >>> + int ret = 0, is_last; >>> + u32 mapping_end, cpos; >>> + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); >>> + struct buffer_head *di_bh = NULL; >>> + struct ocfs2_extent_rec rec; >>> + >>> + if (wait) >>> + ret = ocfs2_inode_lock(inode, &di_bh, 0); >>> + else >>> + ret = ocfs2_try_inode_lock(inode, &di_bh, 0); >>> + if (ret) >>> + goto out; >>> + >>> + if (wait) >>> + down_read(&OCFS2_I(inode)->ip_alloc_sem); >>> + else { >>> + if (!down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem)) { >>> + ret = -EAGAIN; >>> + goto out_unlock1; >>> + } >>> + } >>> + >>> + if ((OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) && >>> + ((map_start + map_len) <= i_size_read(inode))) >>> + goto out_unlock2; >>> + >>> + cpos = map_start >> osb->s_clustersize_bits; >>> + mapping_end = ocfs2_clusters_for_bytes(inode->i_sb, >>> + map_start + map_len); >>> + is_last = 0; >>> + while (cpos < mapping_end && !is_last) { >>> + ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos, >>> + NULL, &rec, &is_last); >>> + if (ret) { >>> + mlog_errno(ret); >>> + goto out_unlock2; >>> + } >>> + >>> + if (rec.e_blkno == 0ULL) >>> + break; >>> + >>> + if (rec.e_flags & OCFS2_EXT_REFCOUNTED) >>> + break; >>> + >>> + cpos = le32_to_cpu(rec.e_cpos) + >>> + le16_to_cpu(rec.e_leaf_clusters); >>> + } >>> + >>> + if (cpos < mapping_end) >>> + ret = 1; >>> + >>> +out_unlock2: >>> + brelse(di_bh); >>> + >>> + up_read(&OCFS2_I(inode)->ip_alloc_sem); >>> + >>> +out_unlock1: >> Should brelse(di_bh) be here? > If the code jumps to out_unlock1 directly, the di_bh pointer should be NULL, it is not necessary to release. > Umm... No, once going out here, we have already taken inode lock. So di_bh should be released. >> >>> + ocfs2_inode_unlock(inode, 0); >>> + >>> +out: >>> + return (ret ? 0 : 1); >> I don't think EAGAIN and other error code can be handled the same. We >> have to distinguish them. > Ok, I think we can add one line log to report the error in case the error is not EAGAIN. > My point is, there is no need to try again in several cases, e.g. EROFS returned by ocfs2_get_clusters_nocache. >> >> Thanks, >> Joseph >> >>> +} >>> + >>> int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int >> whence) >>> { >>> struct inode *inode = file->f_mapping->host; >>> diff --git a/fs/ocfs2/extent_map.h b/fs/ocfs2/extent_map.h >>> index 67ea57d..fd9e86a 100644 >>> --- a/fs/ocfs2/extent_map.h >>> +++ b/fs/ocfs2/extent_map.h >>> @@ -53,6 +53,9 @@ int ocfs2_extent_map_get_blocks(struct inode *inode, u64 >> v_blkno, u64 *p_blkno, >>> int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, >>> u64 map_start, u64 map_len); >>> >>> +int ocfs2_overwrite_io(struct inode *inode, u64 map_start, u64 map_len, >>> + int wait); >>> + >>> int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int >> origin); >>> >>> int ocfs2_xattr_get_clusters(struct inode *inode, u32 v_cluster, >>> > From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joseph Qi Date: Tue, 28 Nov 2017 14:51:45 +0800 Subject: [Ocfs2-devel] [PATCH 2/3] ocfs2: add ocfs2_overwrite_io function In-Reply-To: <5A1D49E5020000F90009AC66@prv-mh.provo.novell.com> References: <1511775987-841-1-git-send-email-ghe@suse.com> <1511775987-841-3-git-send-email-ghe@suse.com> <123f1322-d453-4aca-ac95-63d6f90fd8a2@gmail.com> <5A1D49E5020000F90009AC66@prv-mh.provo.novell.com> Message-ID: <805fb849-dcc7-cbbc-02af-1c6116a88957@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Gang He , jlbec@evilplan.org, hch@lst.de, Goldwyn Rodrigues , mfasheh@versity.com Cc: ocfs2-devel@oss.oracle.com, linux-kernel@vger.kernel.org On 17/11/28 11:35, Gang He wrote: > Hello Joseph, > > >>>> >> Hi Gang, >> >> On 17/11/27 17:46, Gang He wrote: >>> Add ocfs2_overwrite_io function, which is used to judge if >>> overwrite allocated blocks, otherwise, the write will bring extra >>> block allocation overhead. >>> >>> Signed-off-by: Gang He >>> --- >>> fs/ocfs2/extent_map.c | 67 >> +++++++++++++++++++++++++++++++++++++++++++++++++++ >>> fs/ocfs2/extent_map.h | 3 +++ >>> 2 files changed, 70 insertions(+) >>> >>> diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c >>> index e4719e0..98bf325 100644 >>> --- a/fs/ocfs2/extent_map.c >>> +++ b/fs/ocfs2/extent_map.c >>> @@ -832,6 +832,73 @@ int ocfs2_fiemap(struct inode *inode, struct >> fiemap_extent_info *fieinfo, >>> return ret; >>> } >>> >>> +/* Is IO overwriting allocated blocks? */ >>> +int ocfs2_overwrite_io(struct inode *inode, u64 map_start, u64 map_len, >>> + int wait) >>> +{ >>> + int ret = 0, is_last; >>> + u32 mapping_end, cpos; >>> + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); >>> + struct buffer_head *di_bh = NULL; >>> + struct ocfs2_extent_rec rec; >>> + >>> + if (wait) >>> + ret = ocfs2_inode_lock(inode, &di_bh, 0); >>> + else >>> + ret = ocfs2_try_inode_lock(inode, &di_bh, 0); >>> + if (ret) >>> + goto out; >>> + >>> + if (wait) >>> + down_read(&OCFS2_I(inode)->ip_alloc_sem); >>> + else { >>> + if (!down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem)) { >>> + ret = -EAGAIN; >>> + goto out_unlock1; >>> + } >>> + } >>> + >>> + if ((OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) && >>> + ((map_start + map_len) <= i_size_read(inode))) >>> + goto out_unlock2; >>> + >>> + cpos = map_start >> osb->s_clustersize_bits; >>> + mapping_end = ocfs2_clusters_for_bytes(inode->i_sb, >>> + map_start + map_len); >>> + is_last = 0; >>> + while (cpos < mapping_end && !is_last) { >>> + ret = ocfs2_get_clusters_nocache(inode, di_bh, cpos, >>> + NULL, &rec, &is_last); >>> + if (ret) { >>> + mlog_errno(ret); >>> + goto out_unlock2; >>> + } >>> + >>> + if (rec.e_blkno == 0ULL) >>> + break; >>> + >>> + if (rec.e_flags & OCFS2_EXT_REFCOUNTED) >>> + break; >>> + >>> + cpos = le32_to_cpu(rec.e_cpos) + >>> + le16_to_cpu(rec.e_leaf_clusters); >>> + } >>> + >>> + if (cpos < mapping_end) >>> + ret = 1; >>> + >>> +out_unlock2: >>> + brelse(di_bh); >>> + >>> + up_read(&OCFS2_I(inode)->ip_alloc_sem); >>> + >>> +out_unlock1: >> Should brelse(di_bh) be here? > If the code jumps to out_unlock1 directly, the di_bh pointer should be NULL, it is not necessary to release. > Umm... No, once going out here, we have already taken inode lock. So di_bh should be released. >> >>> + ocfs2_inode_unlock(inode, 0); >>> + >>> +out: >>> + return (ret ? 0 : 1); >> I don't think EAGAIN and other error code can be handled the same. We >> have to distinguish them. > Ok, I think we can add one line log to report the error in case the error is not EAGAIN. > My point is, there is no need to try again in several cases, e.g. EROFS returned by ocfs2_get_clusters_nocache. >> >> Thanks, >> Joseph >> >>> +} >>> + >>> int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int >> whence) >>> { >>> struct inode *inode = file->f_mapping->host; >>> diff --git a/fs/ocfs2/extent_map.h b/fs/ocfs2/extent_map.h >>> index 67ea57d..fd9e86a 100644 >>> --- a/fs/ocfs2/extent_map.h >>> +++ b/fs/ocfs2/extent_map.h >>> @@ -53,6 +53,9 @@ int ocfs2_extent_map_get_blocks(struct inode *inode, u64 >> v_blkno, u64 *p_blkno, >>> int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, >>> u64 map_start, u64 map_len); >>> >>> +int ocfs2_overwrite_io(struct inode *inode, u64 map_start, u64 map_len, >>> + int wait); >>> + >>> int ocfs2_seek_data_hole_offset(struct file *file, loff_t *offset, int >> origin); >>> >>> int ocfs2_xattr_get_clusters(struct inode *inode, u32 v_cluster, >>> >