Re: [PATCH v17 07/11] xfs: Hoist xfs_attr_node_addname

[Chandan Babu R <chandanrlinux@gmail.com>]

On 16 Apr 2021 at 14:50, Allison Henderson wrote:
> This patch hoists the later half of xfs_attr_node_addname into
> the calling function.  We do this because it is this area that
> will need the most state management, and we want to keep such
> code in the same scope as much as possible
>

The changes look good to me.

Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>

> Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
> Reviewed-by: Brian Foster <bfoster@redhat.com>
> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
> ---
>  fs/xfs/libxfs/xfs_attr.c | 157 +++++++++++++++++++++++------------------------
>  1 file changed, 76 insertions(+), 81 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
> index 16159f6..80212d2 100644
> --- a/fs/xfs/libxfs/xfs_attr.c
> +++ b/fs/xfs/libxfs/xfs_attr.c
> @@ -52,6 +52,7 @@ STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp);
>   * Internal routines when attribute list is more than one block.
>   */
>  STATIC int xfs_attr_node_get(xfs_da_args_t *args);
> +STATIC void xfs_attr_restore_rmt_blk(struct xfs_da_args *args);
>  STATIC int xfs_attr_node_addname(struct xfs_da_args *args,
>  				 struct xfs_da_state *state);
>  STATIC int xfs_attr_node_addname_find_attr(struct xfs_da_args *args,
> @@ -270,8 +271,8 @@ xfs_attr_set_args(
>  	struct xfs_da_args	*args)
>  {
>  	struct xfs_inode	*dp = args->dp;
> -	struct xfs_da_state     *state;
> -	int			error;
> +	struct xfs_da_state     *state = NULL;
> +	int			error = 0;
>  
>  	/*
>  	 * If the attribute list is already in leaf format, jump straight to
> @@ -322,8 +323,77 @@ xfs_attr_set_args(
>  			return error;
>  		error = xfs_attr_node_addname(args, state);
>  	} while (error == -EAGAIN);
> +	if (error)
> +		return error;
> +
> +	/*
> +	 * Commit the leaf addition or btree split and start the next
> +	 * trans in the chain.
> +	 */
> +	error = xfs_trans_roll_inode(&args->trans, dp);
> +	if (error)
> +		goto out;
> +
> +	/*
> +	 * If there was an out-of-line value, allocate the blocks we
> +	 * identified for its storage and copy the value.  This is done
> +	 * after we create the attribute so that we don't overflow the
> +	 * maximum size of a transaction and/or hit a deadlock.
> +	 */
> +	if (args->rmtblkno > 0) {
> +		error = xfs_attr_rmtval_set(args);
> +		if (error)
> +			return error;
> +	}
> +
> +	if (!(args->op_flags & XFS_DA_OP_RENAME)) {
> +		/*
> +		 * Added a "remote" value, just clear the incomplete flag.
> +		 */
> +		if (args->rmtblkno > 0)
> +			error = xfs_attr3_leaf_clearflag(args);
> +		goto out;
> +	}
> +
> +	/*
> +	 * If this is an atomic rename operation, we must "flip" the incomplete
> +	 * flags on the "new" and "old" attribute/value pairs so that one
> +	 * disappears and one appears atomically.  Then we must remove the "old"
> +	 * attribute/value pair.
> +	 *
> +	 * In a separate transaction, set the incomplete flag on the "old" attr
> +	 * and clear the incomplete flag on the "new" attr.
> +	 */
> +	error = xfs_attr3_leaf_flipflags(args);
> +	if (error)
> +		goto out;
> +	/*
> +	 * Commit the flag value change and start the next trans in series
> +	 */
> +	error = xfs_trans_roll_inode(&args->trans, args->dp);
> +	if (error)
> +		goto out;
> +
> +	/*
> +	 * Dismantle the "old" attribute/value pair by removing a "remote" value
> +	 * (if it exists).
> +	 */
> +	xfs_attr_restore_rmt_blk(args);
> +
> +	if (args->rmtblkno) {
> +		error = xfs_attr_rmtval_invalidate(args);
> +		if (error)
> +			return error;
> +
> +		error = xfs_attr_rmtval_remove(args);
> +		if (error)
> +			return error;
> +	}
>  
> +	error = xfs_attr_node_addname_clear_incomplete(args);
> +out:
>  	return error;
> +
>  }
>  
>  /*
> @@ -957,7 +1027,7 @@ xfs_attr_node_addname(
>  {
>  	struct xfs_da_state_blk	*blk;
>  	struct xfs_inode	*dp;
> -	int			retval, error;
> +	int			error;
>  
>  	trace_xfs_attr_node_addname(args);
>  
> @@ -965,8 +1035,8 @@ xfs_attr_node_addname(
>  	blk = &state->path.blk[state->path.active-1];
>  	ASSERT(blk->magic == XFS_ATTR_LEAF_MAGIC);
>  
> -	retval = xfs_attr3_leaf_add(blk->bp, state->args);
> -	if (retval == -ENOSPC) {
> +	error = xfs_attr3_leaf_add(blk->bp, state->args);
> +	if (error == -ENOSPC) {
>  		if (state->path.active == 1) {
>  			/*
>  			 * Its really a single leaf node, but it had
> @@ -1012,85 +1082,10 @@ xfs_attr_node_addname(
>  		xfs_da3_fixhashpath(state, &state->path);
>  	}
>  
> -	/*
> -	 * Kill the state structure, we're done with it and need to
> -	 * allow the buffers to come back later.
> -	 */
> -	xfs_da_state_free(state);
> -	state = NULL;
> -
> -	/*
> -	 * Commit the leaf addition or btree split and start the next
> -	 * trans in the chain.
> -	 */
> -	error = xfs_trans_roll_inode(&args->trans, dp);
> -	if (error)
> -		goto out;
> -
> -	/*
> -	 * If there was an out-of-line value, allocate the blocks we
> -	 * identified for its storage and copy the value.  This is done
> -	 * after we create the attribute so that we don't overflow the
> -	 * maximum size of a transaction and/or hit a deadlock.
> -	 */
> -	if (args->rmtblkno > 0) {
> -		error = xfs_attr_rmtval_set(args);
> -		if (error)
> -			return error;
> -	}
> -
> -	if (!(args->op_flags & XFS_DA_OP_RENAME)) {
> -		/*
> -		 * Added a "remote" value, just clear the incomplete flag.
> -		 */
> -		if (args->rmtblkno > 0)
> -			error = xfs_attr3_leaf_clearflag(args);
> -		retval = error;
> -		goto out;
> -	}
> -
> -	/*
> -	 * If this is an atomic rename operation, we must "flip" the incomplete
> -	 * flags on the "new" and "old" attribute/value pairs so that one
> -	 * disappears and one appears atomically.  Then we must remove the "old"
> -	 * attribute/value pair.
> -	 *
> -	 * In a separate transaction, set the incomplete flag on the "old" attr
> -	 * and clear the incomplete flag on the "new" attr.
> -	 */
> -	error = xfs_attr3_leaf_flipflags(args);
> -	if (error)
> -		goto out;
> -	/*
> -	 * Commit the flag value change and start the next trans in series
> -	 */
> -	error = xfs_trans_roll_inode(&args->trans, args->dp);
> -	if (error)
> -		goto out;
> -
> -	/*
> -	 * Dismantle the "old" attribute/value pair by removing a "remote" value
> -	 * (if it exists).
> -	 */
> -	xfs_attr_restore_rmt_blk(args);
> -
> -	if (args->rmtblkno) {
> -		error = xfs_attr_rmtval_invalidate(args);
> -		if (error)
> -			return error;
> -
> -		error = xfs_attr_rmtval_remove(args);
> -		if (error)
> -			return error;
> -	}
> -
> -	error = xfs_attr_node_addname_clear_incomplete(args);
>  out:
>  	if (state)
>  		xfs_da_state_free(state);
> -	if (error)
> -		return error;
> -	return retval;
> +	return error;
>  }


-- 
chandan