| Message ID | 59ED80E6.4030600@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hello Alex, Base on your bug description, I think that the fix should be OK. But I suggest you to use more clear function name in this patch. 1) For new-added function ocfs2_get_block_lock(), I think that it is better if the function name is ocfs2_dio_rd_get_block(). 2) Then, rename the original function ocfs2_dio_get_block() to ocfs2_dio_wr_get_block(). Why? Since this function looks to only be used by direct IO (read) mode, we should make the function name more clear, do NOT make other developer to misunderstand/misuse it in the future. Thanks Gang >>> > The ip_alloc_sem should be taken in ocfs2_get_block() when reading file > in DIRECT mode to prevent concurrent access to extent tree with > ocfs2_dio_end_io_write(), which may cause BUGON in > ocfs2_get_clusters_nocache()->BUG_ON(v_cluster < le32_to_cpu(rec->e_cpos)) > > Fixes: c15471f79506 ("ocfs2: fix sparse file & data ordering issue in direct > io") > > Signed-off-by: Alex Chen <alex.chen@huawei.com> > Reviewed-by: Jun Piao <piaojun@huawei.com> > Acked-by: Changwei Ge <ge.changwei@h3c.com> > > --- > fs/ocfs2/aops.c | 22 ++++++++++++++++------ > 1 file changed, 16 insertions(+), 6 deletions(-) > > diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c > index 88a31e9..29607d9 100644 > --- a/fs/ocfs2/aops.c > +++ b/fs/ocfs2/aops.c > @@ -134,6 +134,19 @@ static int ocfs2_symlink_get_block(struct inode *inode, > sector_t iblock, > return err; > } > > +static int ocfs2_get_block_lock(struct inode *inode, sector_t iblock, > + struct buffer_head *bh_result, int create) > +{ > + int ret = 0; > + struct ocfs2_inode_info *oi = OCFS2_I(inode); > + > + down_read(&oi->ip_alloc_sem); > + ret = ocfs2_get_block(inode, iblock, bh_result, create); > + up_read(&oi->ip_alloc_sem); > + > + return ret; > +} > + > int ocfs2_get_block(struct inode *inode, sector_t iblock, > struct buffer_head *bh_result, int create) > { > @@ -2154,12 +2167,9 @@ static int ocfs2_dio_get_block(struct inode *inode, > sector_t iblock, > * while file size will be changed. > */ > if (pos + total_len <= i_size_read(inode)) { > - down_read(&oi->ip_alloc_sem); > - /* This is the fast path for re-write. */ > - ret = ocfs2_get_block(inode, iblock, bh_result, create); > - > - up_read(&oi->ip_alloc_sem); > > + /* This is the fast path for re-write. */ > + ret = ocfs2_get_block_lock(inode, iblock, bh_result, create); > if (buffer_mapped(bh_result) && > !buffer_new(bh_result) && > ret == 0) > @@ -2424,7 +2434,7 @@ static ssize_t ocfs2_direct_IO(struct kiocb *iocb, > struct iov_iter *iter) > return 0; > > if (iov_iter_rw(iter) == READ) > - get_block = ocfs2_get_block; > + get_block = ocfs2_get_block_lock; > else > get_block = ocfs2_dio_get_block; > > -- > 1.9.5.msysgit.1 > > > _______________________________________________ > Ocfs2-devel mailing list > Ocfs2-devel@oss.oracle.com > https://oss.oracle.com/mailman/listinfo/ocfs2-devel
Hi Everybody, Thanks for your reviews. I agree with Gang to make function name ocfs2_get_block_lock() more readable. But the ocfs2_get_block_lock() may be called by the ocfs2_dio_get_block() in re-write sitiation, so I don't think the ocfs2_dio_rd_get_block() is a better name. I agree with Joseph and rename it to ocfs2_lock_get_block(). BTW, I think the ocfs2_dio_wr_get_block() is more suitable for the ocfs2_dio_get_block(). Please give me any feedback if you have any suggestions. Thanks Alex On 2017/10/23 15:16, Gang He wrote: > Hello Alex, > > Base on your bug description, I think that the fix should be OK. > But I suggest you to use more clear function name in this patch. > 1) For new-added function ocfs2_get_block_lock(), I think that it is better if the function name is ocfs2_dio_rd_get_block(). > 2) Then, rename the original function ocfs2_dio_get_block() to ocfs2_dio_wr_get_block(). > Why? > Since this function looks to only be used by direct IO (read) mode, > we should make the function name more clear, do NOT make other developer to misunderstand/misuse it in the future. > > Thanks > Gang > > >>>> >> The ip_alloc_sem should be taken in ocfs2_get_block() when reading file >> in DIRECT mode to prevent concurrent access to extent tree with >> ocfs2_dio_end_io_write(), which may cause BUGON in >> ocfs2_get_clusters_nocache()->BUG_ON(v_cluster < le32_to_cpu(rec->e_cpos)) >> >> Fixes: c15471f79506 ("ocfs2: fix sparse file & data ordering issue in direct >> io") >> >> Signed-off-by: Alex Chen <alex.chen@huawei.com> >> Reviewed-by: Jun Piao <piaojun@huawei.com> >> Acked-by: Changwei Ge <ge.changwei@h3c.com> >> >> --- >> fs/ocfs2/aops.c | 22 ++++++++++++++++------ >> 1 file changed, 16 insertions(+), 6 deletions(-) >> >> diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c >> index 88a31e9..29607d9 100644 >> --- a/fs/ocfs2/aops.c >> +++ b/fs/ocfs2/aops.c >> @@ -134,6 +134,19 @@ static int ocfs2_symlink_get_block(struct inode *inode, >> sector_t iblock, >> return err; >> } >> >> +static int ocfs2_get_block_lock(struct inode *inode, sector_t iblock, >> + struct buffer_head *bh_result, int create) >> +{ >> + int ret = 0; >> + struct ocfs2_inode_info *oi = OCFS2_I(inode); >> + >> + down_read(&oi->ip_alloc_sem); >> + ret = ocfs2_get_block(inode, iblock, bh_result, create); >> + up_read(&oi->ip_alloc_sem); >> + >> + return ret; >> +} >> + >> int ocfs2_get_block(struct inode *inode, sector_t iblock, >> struct buffer_head *bh_result, int create) >> { >> @@ -2154,12 +2167,9 @@ static int ocfs2_dio_get_block(struct inode *inode, >> sector_t iblock, >> * while file size will be changed. >> */ >> if (pos + total_len <= i_size_read(inode)) { >> - down_read(&oi->ip_alloc_sem); >> - /* This is the fast path for re-write. */ >> - ret = ocfs2_get_block(inode, iblock, bh_result, create); >> - >> - up_read(&oi->ip_alloc_sem); >> >> + /* This is the fast path for re-write. */ >> + ret = ocfs2_get_block_lock(inode, iblock, bh_result, create); >> if (buffer_mapped(bh_result) && >> !buffer_new(bh_result) && >> ret == 0) >> @@ -2424,7 +2434,7 @@ static ssize_t ocfs2_direct_IO(struct kiocb *iocb, >> struct iov_iter *iter) >> return 0; >> >> if (iov_iter_rw(iter) == READ) >> - get_block = ocfs2_get_block; >> + get_block = ocfs2_get_block_lock; >> else >> get_block = ocfs2_dio_get_block; >> >> -- >> 1.9.5.msysgit.1 >> >> >> _______________________________________________ >> Ocfs2-devel mailing list >> Ocfs2-devel@oss.oracle.com >> https://oss.oracle.com/mailman/listinfo/ocfs2-devel > > > . >
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 88a31e9..29607d9 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -134,6 +134,19 @@ static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock, return err; } +static int ocfs2_get_block_lock(struct inode *inode, sector_t iblock, + struct buffer_head *bh_result, int create) +{ + int ret = 0; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + + down_read(&oi->ip_alloc_sem); + ret = ocfs2_get_block(inode, iblock, bh_result, create); + up_read(&oi->ip_alloc_sem); + + return ret; +} + int ocfs2_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create) { @@ -2154,12 +2167,9 @@ static int ocfs2_dio_get_block(struct inode *inode, sector_t iblock, * while file size will be changed. */ if (pos + total_len <= i_size_read(inode)) { - down_read(&oi->ip_alloc_sem); - /* This is the fast path for re-write. */ - ret = ocfs2_get_block(inode, iblock, bh_result, create); - - up_read(&oi->ip_alloc_sem); + /* This is the fast path for re-write. */ + ret = ocfs2_get_block_lock(inode, iblock, bh_result, create); if (buffer_mapped(bh_result) && !buffer_new(bh_result) && ret == 0) @@ -2424,7 +2434,7 @@ static ssize_t ocfs2_direct_IO(struct kiocb *iocb, struct iov_iter *iter) return 0; if (iov_iter_rw(iter) == READ) - get_block = ocfs2_get_block; + get_block = ocfs2_get_block_lock; else get_block = ocfs2_dio_get_block;
The ip_alloc_sem should be taken in ocfs2_get_block() when reading file in DIRECT mode to prevent concurrent access to extent tree with ocfs2_dio_end_io_write(), which may cause BUGON in ocfs2_get_clusters_nocache()->BUG_ON(v_cluster < le32_to_cpu(rec->e_cpos)) Fixes: c15471f79506 ("ocfs2: fix sparse file & data ordering issue in direct io") Signed-off-by: Alex Chen <alex.chen@huawei.com> Reviewed-by: Jun Piao <piaojun@huawei.com> Acked-by: Changwei Ge <ge.changwei@h3c.com> --- fs/ocfs2/aops.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-)