Re: [PATCH v5] ocfs2: Let ocfs2_setattr use new truncate sequence.

[Tao Ma <tao.ma@oracle.com>]

Hi Al and Christoph,
	can this patch be added to the vfs-2.6.git?
	Or I should ask Joel to include it in ocfs2.git?

btw, I think both Nick and Joel have acked this patch?

Regards,
Tao

On 06/11/2010 03:19 PM, Tao Ma wrote:
> Let ocfs2 use the new truncate sequence. The changes include:
> 1. Move inode_change_ok into cluster lock and remove inode_newsize_ok.
> 2. Use truncate_setsize directly since we don't implement our
>     own ->truncate and what we need is "update i_size and
>     truncate_pagecache" which truncate_setsize now does.
> 3. Change some i_size_read to inode->i_size in ocfs2_setattr
>     since we have i_muext held.
> 4. For direct write, ocfs2 actually don't allow write to pass
>     i_size(see ocfs2_prepare_inode_for_write), so we don't have
>     a chance to increase i_size. So remove the bogus check.
>
> Cc: Joel Becker<joel.becker@oracle.com>
> Cc: Christoph Hellwig<hch@lst.de>
> Cc: Nick Piggin<npiggin@suse.de>
> Signed-off-by: Tao Ma<tao.ma@oracle.com>
> ---
>   fs/ocfs2/file.c |   47 +++++++++++------------------------------------
>   1 files changed, 11 insertions(+), 36 deletions(-)
>
> diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
> index 1fb0985..98b1f54 100644
> --- a/fs/ocfs2/file.c
> +++ b/fs/ocfs2/file.c
> @@ -960,13 +960,9 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
>   		return 0;
>   	}
>
> -	status = inode_change_ok(inode, attr);
> -	if (status)
> -		return status;
> -
>   	if (is_quota_modification(inode, attr))
>   		dquot_initialize(inode);
> -	size_change = S_ISREG(inode->i_mode)&&  attr->ia_valid&  ATTR_SIZE;
> +	size_change = attr->ia_valid&  ATTR_SIZE;
>   	if (size_change) {
>   		status = ocfs2_rw_lock(inode, 1);
>   		if (status<  0) {
> @@ -982,12 +978,12 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
>   		goto bail_unlock_rw;
>   	}
>
> -	if (size_change&&  attr->ia_size != i_size_read(inode)) {
> -		status = inode_newsize_ok(inode, attr->ia_size);
> -		if (status)
> -			goto bail_unlock;
> +	status = inode_change_ok(inode, attr);
> +	if (status)
> +		goto bail_unlock;
>
> -		if (i_size_read(inode)>  attr->ia_size) {
> +	if (size_change&&  attr->ia_size != inode->i_size) {
> +		if (inode->i_size>  attr->ia_size) {
>   			if (ocfs2_should_order_data(inode)) {
>   				status = ocfs2_begin_ordered_truncate(inode,
>   								      attr->ia_size);
> @@ -1052,22 +1048,12 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
>   	}
>
>   	/*
> -	 * This will intentionally not wind up calling truncate_setsize(),
> -	 * since all the work for a size change has been done above.
> -	 * Otherwise, we could get into problems with truncate as
> -	 * ip_alloc_sem is used there to protect against i_size
> -	 * changes.
> -	 *
> -	 * XXX: this means the conditional below can probably be removed.
> +	 * Since all the work for a size change has been done above.
> +	 * Call truncate_setsize directly to change size and truncate
> +	 * pagecache.
>   	 */
> -	if ((attr->ia_valid&  ATTR_SIZE)&&
> -	    attr->ia_size != i_size_read(inode)) {
> -		status = vmtruncate(inode, attr->ia_size);
> -		if (status) {
> -			mlog_errno(status);
> -			goto bail_commit;
> -		}
> -	}
> +	if ((attr->ia_valid&  ATTR_SIZE)&&  attr->ia_size != inode->i_size)
> +		truncate_setsize(inode, attr->ia_size);
>
>   	setattr_copy(inode, attr);
>   	mark_inode_dirty(inode);
> @@ -2122,17 +2108,6 @@ relock:
>   		written = generic_file_direct_write(iocb, iov,&nr_segs, *ppos,
>   						    ppos, count, ocount);
>   		if (written<  0) {
> -			/*
> -			 * direct write may have instantiated a few
> -			 * blocks outside i_size. Trim these off again.
> -			 * Don't need i_size_read because we hold i_mutex.
> -			 *
> -			 * XXX(truncate): this looks buggy because ocfs2 did not
> -			 * actually implement ->truncate.  Take a look at
> -			 * the new truncate sequence and update this accordingly
> -			 */
> -			if (*ppos + count>  inode->i_size)
> -				truncate_setsize(inode, inode->i_size);
>   			ret = written;
>   			goto out_dio;
>   		}