Hi Alex, Sorry for replaying your mail so late.
>>> > Hi Gang, > > On 2017/12/1 6:24, a...@linux-foundation.org wrote: >> From: Gang He <g...@suse.com> >> Subject: ocfs2: add ocfs2_overwrite_io() >> >> Add ocfs2_overwrite_io(), which is used to judge if overwrite allocated >> blocks, otherwise, the write will bring extra block allocation overhead. >> >> [g...@suse.com: v2] >> Link: > https://urldefense.proofpoint.com/v2/url?u=http-3A__lkml.kernel.org_r_151194 > 4612-2D9629-2D3-2Dgit-2Dsend-2Demail-2Dghe-40suse.com&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8P > Zh8Bv7qIrMUB65eapI_JnE&r=C7gAd4uDxlAvTdc0vmU6X8CMk6L2iDY8-HD0qT6Fo7Y&m=C4AZ7lGI2- > gfFtbla8puNvYIA3a9Cr_XOH6oyx94oGo&s=QhxdPyP9gdEJZTa2UhuSk0x7ENXyGXUOIBV_LyP8oZ > w&e= >> Link: > https://urldefense.proofpoint.com/v2/url?u=http-3A__lkml.kernel.org_r_151177 > 5987-2D841-2D3-2Dgit-2Dsend-2Demail-2Dghe-40suse.com&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZ > h8Bv7qIrMUB65eapI_JnE&r=C7gAd4uDxlAvTdc0vmU6X8CMk6L2iDY8-HD0qT6Fo7Y&m=C4AZ7lGI2-g > fFtbla8puNvYIA3a9Cr_XOH6oyx94oGo&s=T9Ljku-nipBqCaeXWukY2hAwcHQL95gtlU7pS3l1fgs&e > = >> Signed-off-by: Gang He <g...@suse.com> >> Cc: Mark Fasheh <mfas...@versity.com> >> Cc: Joel Becker <jl...@evilplan.org> >> Cc: Junxiao Bi <junxiao...@oracle.com> >> Cc: Joseph Qi <jiangqi...@gmail.com> >> Cc: Changwei Ge <ge.chang...@h3c.com> >> Signed-off-by: Andrew Morton <a...@linux-foundation.org> >> --- >> >> fs/ocfs2/extent_map.c | 41 ++++++++++++++++++++++++++++++++++++++++ >> fs/ocfs2/extent_map.h | 3 ++ >> 2 files changed, 44 insertions(+) >> >> diff -puN fs/ocfs2/extent_map.c~ocfs2-add-ocfs2_overwrite_io-function > fs/ocfs2/extent_map.c >> --- a/fs/ocfs2/extent_map.c~ocfs2-add-ocfs2_overwrite_io-function >> +++ a/fs/ocfs2/extent_map.c >> @@ -832,6 +832,47 @@ out: >> 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) >> +{ >> + 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) && >> + ((map_start + map_len) <= i_size_read(inode))) >> + goto out; >> + > Should we return -EAGAIN directly when the condition > ((OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) && ((map_start + > map_len) > i_size_read(inode))) > is true? Yes, here the code can be improved like as below. e.g. if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) { if (ocfs2_size_fits_inline_data(di_bh, map_start + map_len)) goto out; else return -EAGAIN; } Thanks Gang > > Thanks, > Alex >> + 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 -puN fs/ocfs2/extent_map.h~ocfs2-add-ocfs2_overwrite_io-function > fs/ocfs2/extent_map.h >> --- a/fs/ocfs2/extent_map.h~ocfs2-add-ocfs2_overwrite_io-function >> +++ a/fs/ocfs2/extent_map.h >> @@ -53,6 +53,9 @@ int ocfs2_extent_map_get_blocks(struct i >> 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, >> _ >> >> _______________________________________________ >> Ocfs2-devel mailing list >> Ocfs2-devel@oss.oracle.com >> https://oss.oracle.com/mailman/listinfo/ocfs2-devel >> >> . >> _______________________________________________ Ocfs2-devel mailing list Ocfs2-devel@oss.oracle.com https://oss.oracle.com/mailman/listinfo/ocfs2-devel
