Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751515AbeACFOF convert rfc822-to-8bit (ORCPT + 1 other); Wed, 3 Jan 2018 00:14:05 -0500 Received: from prv-mh.provo.novell.com ([137.65.248.74]:50517 "EHLO prv-mh.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751140AbeACFOD (ORCPT ); Wed, 3 Jan 2018 00:14:03 -0500 Message-Id: <5A4CD719020000F9000A0FE0@prv-mh.provo.novell.com> X-Mailer: Novell GroupWise Internet Agent 14.2.2 Date: Tue, 02 Jan 2018 22:14:01 -0700 From: "Gang He" To: Cc: , , , Subject: Re: [Ocfs2-devel] [PATCH v3 2/3] ocfs2: add ocfs2_overwrite_io function References: <1514455665-16325-1-git-send-email-ghe@suse.com> <1514455665-16325-3-git-send-email-ghe@suse.com> <5A4B666B.1040803@huawei.com> In-Reply-To: <5A4B666B.1040803@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: Hi Alex, >>> > Hi Gang, > > On 2017/12/28 18:07, 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 | 45 +++++++++++++++++++++++++++++++++++++++++++++ >> fs/ocfs2/extent_map.h | 3 +++ >> 2 files changed, 48 insertions(+) >> >> diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c >> index e4719e0..06cb964 100644 >> --- a/fs/ocfs2/extent_map.c >> +++ b/fs/ocfs2/extent_map.c >> @@ -38,6 +38,7 @@ >> #include "inode.h" >> #include "super.h" >> #include "symlink.h" >> +#include "aops.h" >> #include "ocfs2_trace.h" >> >> #include "buffer_head_io.h" >> @@ -832,6 +833,50 @@ 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, struct buffer_head *di_bh, >> + u64 map_start, u64 map_len) > Here can the type of 'map_start' is struct loff_t and map_len is struct > size_t? I prefer to use the detailed types for file start address and length in ocfs2_overwrite_io() function declaration, then here will be a potential type conversion (loff_t -> u64, size_t -> u64), I think this conversion should be considered as expectation. Since our OCFS2 is a 64 bit file system, the related data types do not change, but loff_t and size_t type can change under different architectures (e.g. x86_32, x86_64, etc.). Thanks Gang > > Thanks, > Alex >> +{ >> + int ret = 0, is_last; >> + u32 mapping_end, cpos; >> + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); >> + struct ocfs2_extent_rec rec; >> + >> + if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) { >> + if (ocfs2_size_fits_inline_data(di_bh, map_start + map_len)) >> + return ret; >> + else >> + return -EAGAIN; >> + } >> + >> + 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; >> + } >> + >> + 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 = -EAGAIN; >> +out: >> + return ret; >> +} >> + >> 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..1057586 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, struct buffer_head *di_bh, >> + u64 map_start, u64 map_len); >> + >> 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, >>