2006-11-06 11:05:38

by Steven Whitehouse

Subject: [GFS2] Fix incorrect fs sync behaviour [2/5]

>From 4a221953ed121692aa25998451a57c7f4be8b4f6 Mon Sep 17 00:00:00 2001
From: Steven Whitehouse <[email protected]>
Date: Wed, 1 Nov 2006 09:57:57 -0500
Subject: [PATCH] [GFS2] Fix incorrect fs sync behaviour.

This adds a sync_fs superblock operation for GFS2 and removes
the journal flush from write_super in favour of sync_fs where it
ought to be. This is more or less identical to the way in which ext3
does this.

This bug was pointed out by Russell Cattelan <[email protected]>

Cc: Russell Cattelan <[email protected]>
Signed-off-by: Steven Whitehouse <[email protected]>
---
fs/gfs2/ops_super.c | 44 ++++++++++++++++++++++++++++----------------
1 files changed, 28 insertions(+), 16 deletions(-)

diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c
index 06f06f7..b47d959 100644
--- a/fs/gfs2/ops_super.c
+++ b/fs/gfs2/ops_super.c
@@ -138,16 +138,27 @@ static void gfs2_put_super(struct super_
}

/**
- * gfs2_write_super - disk commit all incore transactions
- * @sb: the filesystem
+ * gfs2_write_super
+ * @sb: the superblock
*
- * This function is called every time sync(2) is called.
- * After this exits, all dirty buffers are synced.
*/

static void gfs2_write_super(struct super_block *sb)
{
+ sb->s_dirt = 0;
+}
+
+/**
+ * gfs2_sync_fs - sync the filesystem
+ * @sb: the superblock
+ *
+ * Flushes the log to disk.
+ */
+static int gfs2_sync_fs(struct super_block *sb, int wait)
+{
+ sb->s_dirt = 0;
gfs2_log_flush(sb->s_fs_info, NULL);
+ return 0;
}

/**
@@ -452,17 +463,18 @@ static void gfs2_destroy_inode(struct in
}

struct super_operations gfs2_super_ops = {
- .alloc_inode = gfs2_alloc_inode,
- .destroy_inode = gfs2_destroy_inode,
- .write_inode = gfs2_write_inode,
- .delete_inode = gfs2_delete_inode,
- .put_super = gfs2_put_super,
- .write_super = gfs2_write_super,
- .write_super_lockfs = gfs2_write_super_lockfs,
- .unlockfs = gfs2_unlockfs,
- .statfs = gfs2_statfs,
- .remount_fs = gfs2_remount_fs,
- .clear_inode = gfs2_clear_inode,
- .show_options = gfs2_show_options,
+ .alloc_inode = gfs2_alloc_inode,
+ .destroy_inode = gfs2_destroy_inode,
+ .write_inode = gfs2_write_inode,
+ .delete_inode = gfs2_delete_inode,
+ .put_super = gfs2_put_super,
+ .write_super = gfs2_write_super,
+ .sync_fs = gfs2_sync_fs,
+ .write_super_lockfs = gfs2_write_super_lockfs,
+ .unlockfs = gfs2_unlockfs,
+ .statfs = gfs2_statfs,
+ .remount_fs = gfs2_remount_fs,
+ .clear_inode = gfs2_clear_inode,
+ .show_options = gfs2_show_options,
};

--
1.4.1

2006-12-01 17:57:41

by Russell Cattelan

Subject: Re: [GFS2] Fix incorrect fs sync behaviour [2/5]

On Mon, 2006-11-06 at 11:07 +0000, Steven Whitehouse wrote:
> >From 4a221953ed121692aa25998451a57c7f4be8b4f6 Mon Sep 17 00:00:00 2001
> From: Steven Whitehouse <[email protected]>
> Date: Wed, 1 Nov 2006 09:57:57 -0500
> Subject: [PATCH] [GFS2] Fix incorrect fs sync behaviour.
>
> This adds a sync_fs superblock operation for GFS2 and removes
> the journal flush from write_super in favour of sync_fs where it
> ought to be. This is more or less identical to the way in which ext3
> does this.
>
> This bug was pointed out by Russell Cattelan <[email protected]>
>
> Cc: Russell Cattelan <[email protected]>
> Signed-off-by: Steven Whitehouse <[email protected]>
> ---
> fs/gfs2/ops_super.c | 44 ++++++++++++++++++++++++++++----------------
> 1 files changed, 28 insertions(+), 16 deletions(-)
>
> diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c
> index 06f06f7..b47d959 100644
> --- a/fs/gfs2/ops_super.c
> +++ b/fs/gfs2/ops_super.c
> @@ -138,16 +138,27 @@ static void gfs2_put_super(struct super_
> }
>
> /**
> - * gfs2_write_super - disk commit all incore transactions
> - * @sb: the filesystem
> + * gfs2_write_super
> + * @sb: the superblock
> *
> - * This function is called every time sync(2) is called.
> - * After this exits, all dirty buffers are synced.
> */
>
> static void gfs2_write_super(struct super_block *sb)
> {
> + sb->s_dirt = 0;
This is a bit different than my original patch?
Are you sure we don't need the s_lock here?


> +}
> +
> +/**
> + * gfs2_sync_fs - sync the filesystem
> + * @sb: the superblock
> + *
> + * Flushes the log to disk.
> + */
> +static int gfs2_sync_fs(struct super_block *sb, int wait)
> +{
> + sb->s_dirt = 0;
> gfs2_log_flush(sb->s_fs_info, NULL);
> + return 0;
> }
>
> /**
> @@ -452,17 +463,18 @@ static void gfs2_destroy_inode(struct in
> }
>
> struct super_operations gfs2_super_ops = {
> - .alloc_inode = gfs2_alloc_inode,
> - .destroy_inode = gfs2_destroy_inode,
> - .write_inode = gfs2_write_inode,
> - .delete_inode = gfs2_delete_inode,
> - .put_super = gfs2_put_super,
> - .write_super = gfs2_write_super,
> - .write_super_lockfs = gfs2_write_super_lockfs,
> - .unlockfs = gfs2_unlockfs,
> - .statfs = gfs2_statfs,
> - .remount_fs = gfs2_remount_fs,
> - .clear_inode = gfs2_clear_inode,
> - .show_options = gfs2_show_options,
> + .alloc_inode = gfs2_alloc_inode,
> + .destroy_inode = gfs2_destroy_inode,
> + .write_inode = gfs2_write_inode,
> + .delete_inode = gfs2_delete_inode,
> + .put_super = gfs2_put_super,
> + .write_super = gfs2_write_super,
> + .sync_fs = gfs2_sync_fs,
> + .write_super_lockfs = gfs2_write_super_lockfs,
> + .unlockfs = gfs2_unlockfs,
> + .statfs = gfs2_statfs,
> + .remount_fs = gfs2_remount_fs,
> + .clear_inode = gfs2_clear_inode,
> + .show_options = gfs2_show_options,
> };
>
--
Russell Cattelan <[email protected]>

2006-12-04 09:09:58

by Steven Whitehouse

Subject: Re: [Cluster-devel] Re: [GFS2] Fix incorrect fs sync behaviour [2/5]

Hi,

On Fri, 2006-12-01 at 11:57 -0600, Russell Cattelan wrote:
> On Mon, 2006-11-06 at 11:07 +0000, Steven Whitehouse wrote:
> > >From 4a221953ed121692aa25998451a57c7f4be8b4f6 Mon Sep 17 00:00:00 2001
> > From: Steven Whitehouse <[email protected]>
> > Date: Wed, 1 Nov 2006 09:57:57 -0500
> > Subject: [PATCH] [GFS2] Fix incorrect fs sync behaviour.
> >
> > This adds a sync_fs superblock operation for GFS2 and removes
> > the journal flush from write_super in favour of sync_fs where it
> > ought to be. This is more or less identical to the way in which ext3
> > does this.
> >
> > This bug was pointed out by Russell Cattelan <[email protected]>
> >
> > Cc: Russell Cattelan <[email protected]>
> > Signed-off-by: Steven Whitehouse <[email protected]>
> > ---
> > fs/gfs2/ops_super.c | 44 ++++++++++++++++++++++++++++----------------
> > 1 files changed, 28 insertions(+), 16 deletions(-)
> >
> > diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c
> > index 06f06f7..b47d959 100644
> > --- a/fs/gfs2/ops_super.c
> > +++ b/fs/gfs2/ops_super.c
> > @@ -138,16 +138,27 @@ static void gfs2_put_super(struct super_
> > }
> >
> > /**
> > - * gfs2_write_super - disk commit all incore transactions
> > - * @sb: the filesystem
> > + * gfs2_write_super
> > + * @sb: the superblock
> > *
> > - * This function is called every time sync(2) is called.
> > - * After this exits, all dirty buffers are synced.
> > */
> >
> > static void gfs2_write_super(struct super_block *sb)
> > {
> > + sb->s_dirt = 0;
> This is a bit different than my original patch?
This was largely taken from the ext3 code as an example, rather than
your patch.

>
> Are you sure we don't need the s_lock here?
>
Yes. See linux-2.6/Documentation/filesystems/Locking:


locking rules:
All may block.
BKL s_lock s_umount
[snip]
write_super: no yes read

it is already held on entry to write_super,

Steve.