Li Dongyang
2010-Apr-17 09:49 UTC
[Ocfs2-devel] [PATCH] ocfs2: avoid direct write if we fall back to buffered v3
when we fall back to buffered write from direct write, we call
__generic_file_aio_write but that will end up doing direct write
even we are only prepared to do buffered write because the file
has O_DIRECT flag set. This is a fix for
https://bugzilla.novell.com/show_bug.cgi?id=591039
revised with Joel's comments.
Signed-off-by: Li Dongyang <lidongyang at novell.com>
---
fs/ocfs2/file.c | 25 ++++++++++++++-----------
1 files changed, 14 insertions(+), 11 deletions(-)
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index de059f4..0c15be9 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1973,18 +1973,18 @@ relock:
/* communicate with ocfs2_dio_end_io */
ocfs2_iocb_set_rw_locked(iocb, rw_level);
- if (direct_io) {
- ret = generic_segment_checks(iov, &nr_segs, &ocount,
- VERIFY_READ);
- if (ret)
- goto out_dio;
+ ret = generic_segment_checks(iov, &nr_segs, &ocount,
+ VERIFY_READ);
+ if (ret)
+ goto out_dio;
- count = ocount;
- ret = generic_write_checks(file, ppos, &count,
- S_ISBLK(inode->i_mode));
- if (ret)
- goto out_dio;
+ count = ocount;
+ ret = generic_write_checks(file, ppos, &count,
+ S_ISBLK(inode->i_mode));
+ if (ret)
+ goto out_dio;
+ if (direct_io) {
written = generic_file_direct_write(iocb, iov, &nr_segs, *ppos,
ppos, count, ocount);
if (written < 0) {
@@ -1999,7 +1999,10 @@ relock:
goto out_dio;
}
} else {
- written = __generic_file_aio_write(iocb, iov, nr_segs, ppos);
+ current->backing_dev_info = file->f_mapping->backing_dev_info;
+ written = generic_file_buffered_write(iocb, iov, nr_segs, *ppos
+ ppos, count, 0);
+ current->backing_dev_info = NULL;
}
out_dio:
--
1.6.4.2
Li Dongyang
2010-Apr-26 09:56 UTC
[Ocfs2-devel] [PATCH] ocfs2: avoid direct write if we fall back to buffered v3
On Saturday 17 April 2010 17:49:10 Li Dongyang wrote:> when we fall back to buffered write from direct write, we call > __generic_file_aio_write but that will end up doing direct write > even we are only prepared to do buffered write because the file > has O_DIRECT flag set. This is a fix for > https://bugzilla.novell.com/show_bug.cgi?id=591039 > revised with Joel's comments. > > Signed-off-by: Li Dongyang <lidongyang at novell.com> > --- > fs/ocfs2/file.c | 25 ++++++++++++++----------- > 1 files changed, 14 insertions(+), 11 deletions(-) > > diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c > index de059f4..0c15be9 100644 > --- a/fs/ocfs2/file.c > +++ b/fs/ocfs2/file.c > @@ -1973,18 +1973,18 @@ relock: > /* communicate with ocfs2_dio_end_io */ > ocfs2_iocb_set_rw_locked(iocb, rw_level); > > - if (direct_io) { > - ret = generic_segment_checks(iov, &nr_segs, &ocount, > - VERIFY_READ); > - if (ret) > - goto out_dio; > + ret = generic_segment_checks(iov, &nr_segs, &ocount, > + VERIFY_READ); > + if (ret) > + goto out_dio; > > - count = ocount; > - ret = generic_write_checks(file, ppos, &count, > - S_ISBLK(inode->i_mode)); > - if (ret) > - goto out_dio; > + count = ocount; > + ret = generic_write_checks(file, ppos, &count, > + S_ISBLK(inode->i_mode)); > + if (ret) > + goto out_dio; > > + if (direct_io) { > written = generic_file_direct_write(iocb, iov, &nr_segs, *ppos, > ppos, count, ocount); > if (written < 0) { > @@ -1999,7 +1999,10 @@ relock: > goto out_dio; > } > } else { > - written = __generic_file_aio_write(iocb, iov, nr_segs, ppos); > + current->backing_dev_info = file->f_mapping->backing_dev_info; > + written = generic_file_buffered_write(iocb, iov, nr_segs, *ppos > + ppos, count, 0); > + current->backing_dev_info = NULL; > } > > out_dio: >Joel, any comments on this update? Br, Li Dongyang
Joel Becker
2010-Apr-26 22:24 UTC
[Ocfs2-devel] [PATCH] ocfs2: avoid direct write if we fall back to buffered v3
On Sat, Apr 17, 2010 at 05:49:10PM +0800, Li Dongyang wrote:> when we fall back to buffered write from direct write, we call > __generic_file_aio_write but that will end up doing direct write > even we are only prepared to do buffered write because the file > has O_DIRECT flag set. This is a fix for > https://bugzilla.novell.com/show_bug.cgi?id=591039 > revised with Joel's comments. > > Signed-off-by: Li Dongyang <lidongyang at novell.com>This looks good to me. I'd like Mark's ack before I push it to merge-window. Joel -- "Sometimes one pays most for the things one gets for nothing." - Albert Einstein Joel Becker Principal Software Developer Oracle E-mail: joel.becker at oracle.com Phone: (650) 506-8127
Joel Becker
2010-Apr-30 20:47 UTC
[Ocfs2-devel] [PATCH] ocfs2: avoid direct write if we fall back to buffered v3
On Sat, Apr 17, 2010 at 05:49:10PM +0800, Li Dongyang wrote:> when we fall back to buffered write from direct write, we call > __generic_file_aio_write but that will end up doing direct write > even we are only prepared to do buffered write because the file > has O_DIRECT flag set. This is a fix for > https://bugzilla.novell.com/show_bug.cgi?id=591039 > revised with Joel's comments.Have you tested this version? I got a compile error:> @@ -1999,7 +1999,10 @@ relock: > goto out_dio; > } > } else { > - written = __generic_file_aio_write(iocb, iov, nr_segs, ppos); > + current->backing_dev_info = file->f_mapping->backing_dev_info; > + written = generic_file_buffered_write(iocb, iov, nr_segs, *ppos > + ppos, count, 0); > + current->backing_dev_info = NULL; > }- written = generic_file_buffered_write(iocb, iov, nr_segs, *ppos + written = generic_file_buffered_write(iocb, iov, nr_segs, *ppos, Joel -- "I think it would be a good idea." - Mahatma Ghandi, when asked what he thought of Western civilization Joel Becker Principal Software Developer Oracle E-mail: joel.becker at oracle.com Phone: (650) 506-8127